astelm/minio
1
0
Fork 0
mirror of https://github.com/pgsty/minio.git synced 2026-07-19 04:00:25 +03:00
Code Issues Packages Projects Releases Wiki Activity

Add support for Kafka as a notifications target (#2869) (#3439)

Browse Source
This commit is contained in:
Aditya Manthramurthy
2016-12-15 21:53:48 +05:30
committed by Harshavardhana
parent 664ff063a1
commit 8e6e9301ce
113 changed files with 16290 additions and 35 deletions
Download Patch File Download Diff File Expand all files Collapse all files
vendor/github.com/davecgh/go-spew/LICENSE
Generated Vendored
+15
View File
@@ -0,0 +1,15 @@
ISC License
Copyright (c) 2012-2016 Dave Collins <dave@davec.name>
Permission to use, copy, modify, and distribute this software for any
purpose with or without fee is hereby granted, provided that the above
copyright notice and this permission notice appear in all copies.
THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
vendor/github.com/davecgh/go-spew/spew/bypass.go
Generated Vendored
+152
View File
@@ -0,0 +1,152 @@
// Copyright (c) 2015-2016 Dave Collins <dave@davec.name>
//
// Permission to use, copy, modify, and distribute this software for any
// purpose with or without fee is hereby granted, provided that the above
// copyright notice and this permission notice appear in all copies.
//
// THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
// WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
// ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
// WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
// OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
// NOTE: Due to the following build constraints, this file will only be compiled
// when the code is not running on Google App Engine, compiled by GopherJS, and
// "-tags safe" is not added to the go build command line. The "disableunsafe"
// tag is deprecated and thus should not be used.
// +build !js,!appengine,!safe,!disableunsafe
package spew
import (
"reflect"
"unsafe"
)
const (
// UnsafeDisabled is a build-time constant which specifies whether or
// not access to the unsafe package is available.
UnsafeDisabled = false
// ptrSize is the size of a pointer on the current arch.
ptrSize = unsafe.Sizeof((*byte)(nil))
)
var (
// offsetPtr, offsetScalar, and offsetFlag are the offsets for the
// internal reflect.Value fields. These values are valid before golang
// commit ecccf07e7f9d which changed the format. The are also valid
// after commit 82f48826c6c7 which changed the format again to mirror
// the original format. Code in the init function updates these offsets
// as necessary.
offsetPtr = uintptr(ptrSize)
offsetScalar = uintptr(0)
offsetFlag = uintptr(ptrSize * 2)
// flagKindWidth and flagKindShift indicate various bits that the
// reflect package uses internally to track kind information.
//
// flagRO indicates whether or not the value field of a reflect.Value is
// read-only.
//
// flagIndir indicates whether the value field of a reflect.Value is
// the actual data or a pointer to the data.
//
// These values are valid before golang commit 90a7c3c86944 which
// changed their positions. Code in the init function updates these
// flags as necessary.
flagKindWidth = uintptr(5)
flagKindShift = uintptr(flagKindWidth - 1)
flagRO = uintptr(1 << 0)
flagIndir = uintptr(1 << 1)
)
func init() {
// Older versions of reflect.Value stored small integers directly in the
// ptr field (which is named val in the older versions). Versions
// between commits ecccf07e7f9d and 82f48826c6c7 added a new field named
// scalar for this purpose which unfortunately came before the flag
// field, so the offset of the flag field is different for those
// versions.
//
// This code constructs a new reflect.Value from a known small integer
// and checks if the size of the reflect.Value struct indicates it has
// the scalar field. When it does, the offsets are updated accordingly.
vv := reflect.ValueOf(0xf00)
if unsafe.Sizeof(vv) == (ptrSize * 4) {
offsetScalar = ptrSize * 2
offsetFlag = ptrSize * 3
}
// Commit 90a7c3c86944 changed the flag positions such that the low
// order bits are the kind. This code extracts the kind from the flags
// field and ensures it's the correct type. When it's not, the flag
// order has been changed to the newer format, so the flags are updated
// accordingly.
upf := unsafe.Pointer(uintptr(unsafe.Pointer(&vv)) + offsetFlag)
upfv := *(*uintptr)(upf)
flagKindMask := uintptr((1<<flagKindWidth - 1) << flagKindShift)
if (upfv&flagKindMask)>>flagKindShift != uintptr(reflect.Int) {
flagKindShift = 0
flagRO = 1 << 5
flagIndir = 1 << 6
// Commit adf9b30e5594 modified the flags to separate the
// flagRO flag into two bits which specifies whether or not the
// field is embedded. This causes flagIndir to move over a bit
// and means that flagRO is the combination of either of the
// original flagRO bit and the new bit.
//
// This code detects the change by extracting what used to be
// the indirect bit to ensure it's set. When it's not, the flag
// order has been changed to the newer format, so the flags are
// updated accordingly.
if upfv&flagIndir == 0 {
flagRO = 3 << 5
flagIndir = 1 << 7
}
}
}
// unsafeReflectValue converts the passed reflect.Value into a one that bypasses
// the typical safety restrictions preventing access to unaddressable and
// unexported data. It works by digging the raw pointer to the underlying
// value out of the protected value and generating a new unprotected (unsafe)
// reflect.Value to it.
//
// This allows us to check for implementations of the Stringer and error
// interfaces to be used for pretty printing ordinarily unaddressable and
// inaccessible values such as unexported struct fields.
func unsafeReflectValue(v reflect.Value) (rv reflect.Value) {
indirects := 1
vt := v.Type()
upv := unsafe.Pointer(uintptr(unsafe.Pointer(&v)) + offsetPtr)
rvf := *(*uintptr)(unsafe.Pointer(uintptr(unsafe.Pointer(&v)) + offsetFlag))
if rvf&flagIndir != 0 {
vt = reflect.PtrTo(v.Type())
indirects++
} else if offsetScalar != 0 {
// The value is in the scalar field when it's not one of the
// reference types.
switch vt.Kind() {
case reflect.Uintptr:
case reflect.Chan:
case reflect.Func:
case reflect.Map:
case reflect.Ptr:
case reflect.UnsafePointer:
default:
upv = unsafe.Pointer(uintptr(unsafe.Pointer(&v)) +
offsetScalar)
}
}
pv := reflect.NewAt(vt, upv)
rv = pv
for i := 0; i < indirects; i++ {
rv = rv.Elem()
}
return rv
}
vendor/github.com/davecgh/go-spew/spew/common.go
Generated Vendored
+341
View File
@@ -0,0 +1,341 @@
/*
* Copyright (c) 2013-2016 Dave Collins <dave@davec.name>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
package spew
import (
"bytes"
"fmt"
"io"
"reflect"
"sort"
"strconv"
)
// Some constants in the form of bytes to avoid string overhead. This mirrors
// the technique used in the fmt package.
var (
panicBytes = []byte("(PANIC=")
plusBytes = []byte("+")
iBytes = []byte("i")
trueBytes = []byte("true")
falseBytes = []byte("false")
interfaceBytes = []byte("(interface {})")
commaNewlineBytes = []byte(",\n")
newlineBytes = []byte("\n")
openBraceBytes = []byte("{")
openBraceNewlineBytes = []byte("{\n")
closeBraceBytes = []byte("}")
asteriskBytes = []byte("*")
colonBytes = []byte(":")
colonSpaceBytes = []byte(": ")
openParenBytes = []byte("(")
closeParenBytes = []byte(")")
spaceBytes = []byte(" ")
pointerChainBytes = []byte("->")
nilAngleBytes = []byte("<nil>")
maxNewlineBytes = []byte("<max depth reached>\n")
maxShortBytes = []byte("<max>")
circularBytes = []byte("<already shown>")
circularShortBytes = []byte("<shown>")
invalidAngleBytes = []byte("<invalid>")
openBracketBytes = []byte("[")
closeBracketBytes = []byte("]")
percentBytes = []byte("%")
precisionBytes = []byte(".")
openAngleBytes = []byte("<")
closeAngleBytes = []byte(">")
openMapBytes = []byte("map[")
closeMapBytes = []byte("]")
lenEqualsBytes = []byte("len=")
capEqualsBytes = []byte("cap=")
)
// hexDigits is used to map a decimal value to a hex digit.
var hexDigits = "0123456789abcdef"
// catchPanic handles any panics that might occur during the handleMethods
// calls.
func catchPanic(w io.Writer, v reflect.Value) {
if err := recover(); err != nil {
w.Write(panicBytes)
fmt.Fprintf(w, "%v", err)
w.Write(closeParenBytes)
}
}
// handleMethods attempts to call the Error and String methods on the underlying
// type the passed reflect.Value represents and outputes the result to Writer w.
//
// It handles panics in any called methods by catching and displaying the error
// as the formatted value.
func handleMethods(cs *ConfigState, w io.Writer, v reflect.Value) (handled bool) {
// We need an interface to check if the type implements the error or
// Stringer interface. However, the reflect package won't give us an
// interface on certain things like unexported struct fields in order
// to enforce visibility rules. We use unsafe, when it's available,
// to bypass these restrictions since this package does not mutate the
// values.
if !v.CanInterface() {
if UnsafeDisabled {
return false
}
v = unsafeReflectValue(v)
}
// Choose whether or not to do error and Stringer interface lookups against
// the base type or a pointer to the base type depending on settings.
// Technically calling one of these methods with a pointer receiver can
// mutate the value, however, types which choose to satisify an error or
// Stringer interface with a pointer receiver should not be mutating their
// state inside these interface methods.
if !cs.DisablePointerMethods && !UnsafeDisabled && !v.CanAddr() {
v = unsafeReflectValue(v)
}
if v.CanAddr() {
v = v.Addr()
}
// Is it an error or Stringer?
switch iface := v.Interface().(type) {
case error:
defer catchPanic(w, v)
if cs.ContinueOnMethod {
w.Write(openParenBytes)
w.Write([]byte(iface.Error()))
w.Write(closeParenBytes)
w.Write(spaceBytes)
return false
}
w.Write([]byte(iface.Error()))
return true
case fmt.Stringer:
defer catchPanic(w, v)
if cs.ContinueOnMethod {
w.Write(openParenBytes)
w.Write([]byte(iface.String()))
w.Write(closeParenBytes)
w.Write(spaceBytes)
return false
}
w.Write([]byte(iface.String()))
return true
}
return false
}
// printBool outputs a boolean value as true or false to Writer w.
func printBool(w io.Writer, val bool) {
if val {
w.Write(trueBytes)
} else {
w.Write(falseBytes)
}
}
// printInt outputs a signed integer value to Writer w.
func printInt(w io.Writer, val int64, base int) {
w.Write([]byte(strconv.FormatInt(val, base)))
}
// printUint outputs an unsigned integer value to Writer w.
func printUint(w io.Writer, val uint64, base int) {
w.Write([]byte(strconv.FormatUint(val, base)))
}
// printFloat outputs a floating point value using the specified precision,
// which is expected to be 32 or 64bit, to Writer w.
func printFloat(w io.Writer, val float64, precision int) {
w.Write([]byte(strconv.FormatFloat(val, 'g', -1, precision)))
}
// printComplex outputs a complex value using the specified float precision
// for the real and imaginary parts to Writer w.
func printComplex(w io.Writer, c complex128, floatPrecision int) {
r := real(c)
w.Write(openParenBytes)
w.Write([]byte(strconv.FormatFloat(r, 'g', -1, floatPrecision)))
i := imag(c)
if i >= 0 {
w.Write(plusBytes)
}
w.Write([]byte(strconv.FormatFloat(i, 'g', -1, floatPrecision)))
w.Write(iBytes)
w.Write(closeParenBytes)
}
// printHexPtr outputs a uintptr formatted as hexidecimal with a leading '0x'
// prefix to Writer w.
func printHexPtr(w io.Writer, p uintptr) {
// Null pointer.
num := uint64(p)
if num == 0 {
w.Write(nilAngleBytes)
return
}
// Max uint64 is 16 bytes in hex + 2 bytes for '0x' prefix
buf := make([]byte, 18)
// It's simpler to construct the hex string right to left.
base := uint64(16)
i := len(buf) - 1
for num >= base {
buf[i] = hexDigits[num%base]
num /= base
i--
}
buf[i] = hexDigits[num]
// Add '0x' prefix.
i--
buf[i] = 'x'
i--
buf[i] = '0'
// Strip unused leading bytes.
buf = buf[i:]
w.Write(buf)
}
// valuesSorter implements sort.Interface to allow a slice of reflect.Value
// elements to be sorted.
type valuesSorter struct {
values []reflect.Value
strings []string // either nil or same len and values
cs *ConfigState
}
// newValuesSorter initializes a valuesSorter instance, which holds a set of
// surrogate keys on which the data should be sorted. It uses flags in
// ConfigState to decide if and how to populate those surrogate keys.
func newValuesSorter(values []reflect.Value, cs *ConfigState) sort.Interface {
vs := &valuesSorter{values: values, cs: cs}
if canSortSimply(vs.values[0].Kind()) {
return vs
}
if !cs.DisableMethods {
vs.strings = make([]string, len(values))
for i := range vs.values {
b := bytes.Buffer{}
if !handleMethods(cs, &b, vs.values[i]) {
vs.strings = nil
break
}
vs.strings[i] = b.String()
}
}
if vs.strings == nil && cs.SpewKeys {
vs.strings = make([]string, len(values))
for i := range vs.values {
vs.strings[i] = Sprintf("%#v", vs.values[i].Interface())
}
}
return vs
}
// canSortSimply tests whether a reflect.Kind is a primitive that can be sorted
// directly, or whether it should be considered for sorting by surrogate keys
// (if the ConfigState allows it).
func canSortSimply(kind reflect.Kind) bool {
// This switch parallels valueSortLess, except for the default case.
switch kind {
case reflect.Bool:
return true
case reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Int:
return true
case reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uint:
return true
case reflect.Float32, reflect.Float64:
return true
case reflect.String:
return true
case reflect.Uintptr:
return true
case reflect.Array:
return true
}
return false
}
// Len returns the number of values in the slice. It is part of the
// sort.Interface implementation.
func (s *valuesSorter) Len() int {
return len(s.values)
}
// Swap swaps the values at the passed indices. It is part of the
// sort.Interface implementation.
func (s *valuesSorter) Swap(i, j int) {
s.values[i], s.values[j] = s.values[j], s.values[i]
if s.strings != nil {
s.strings[i], s.strings[j] = s.strings[j], s.strings[i]
}
}
// valueSortLess returns whether the first value should sort before the second
// value. It is used by valueSorter.Less as part of the sort.Interface
// implementation.
func valueSortLess(a, b reflect.Value) bool {
switch a.Kind() {
case reflect.Bool:
return !a.Bool() && b.Bool()
case reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Int:
return a.Int() < b.Int()
case reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uint:
return a.Uint() < b.Uint()
case reflect.Float32, reflect.Float64:
return a.Float() < b.Float()
case reflect.String:
return a.String() < b.String()
case reflect.Uintptr:
return a.Uint() < b.Uint()
case reflect.Array:
// Compare the contents of both arrays.
l := a.Len()
for i := 0; i < l; i++ {
av := a.Index(i)
bv := b.Index(i)
if av.Interface() == bv.Interface() {
continue
}
return valueSortLess(av, bv)
}
}
return a.String() < b.String()
}
// Less returns whether the value at index i should sort before the
// value at index j. It is part of the sort.Interface implementation.
func (s *valuesSorter) Less(i, j int) bool {
if s.strings == nil {
return valueSortLess(s.values[i], s.values[j])
}
return s.strings[i] < s.strings[j]
}
// sortValues is a sort function that handles both native types and any type that
// can be converted to error or Stringer. Other inputs are sorted according to
// their Value.String() value to ensure display stability.
func sortValues(values []reflect.Value, cs *ConfigState) {
if len(values) == 0 {
return
}
sort.Sort(newValuesSorter(values, cs))
}
vendor/github.com/davecgh/go-spew/spew/config.go
Generated Vendored
+306
View File
@@ -0,0 +1,306 @@
/*
* Copyright (c) 2013-2016 Dave Collins <dave@davec.name>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
package spew
import (
"bytes"
"fmt"
"io"
"os"
)
// ConfigState houses the configuration options used by spew to format and
// display values. There is a global instance, Config, that is used to control
// all top-level Formatter and Dump functionality. Each ConfigState instance
// provides methods equivalent to the top-level functions.
//
// The zero value for ConfigState provides no indentation. You would typically
// want to set it to a space or a tab.
//
// Alternatively, you can use NewDefaultConfig to get a ConfigState instance
// with default settings. See the documentation of NewDefaultConfig for default
// values.
type ConfigState struct {
// Indent specifies the string to use for each indentation level. The
// global config instance that all top-level functions use set this to a
// single space by default. If you would like more indentation, you might
// set this to a tab with "\t" or perhaps two spaces with " ".
Indent string
// MaxDepth controls the maximum number of levels to descend into nested
// data structures. The default, 0, means there is no limit.
//
// NOTE: Circular data structures are properly detected, so it is not
// necessary to set this value unless you specifically want to limit deeply
// nested data structures.
MaxDepth int
// DisableMethods specifies whether or not error and Stringer interfaces are
// invoked for types that implement them.
DisableMethods bool
// DisablePointerMethods specifies whether or not to check for and invoke
// error and Stringer interfaces on types which only accept a pointer
// receiver when the current type is not a pointer.
//
// NOTE: This might be an unsafe action since calling one of these methods
// with a pointer receiver could technically mutate the value, however,
// in practice, types which choose to satisify an error or Stringer
// interface with a pointer receiver should not be mutating their state
// inside these interface methods. As a result, this option relies on
// access to the unsafe package, so it will not have any effect when
// running in environments without access to the unsafe package such as
// Google App Engine or with the "safe" build tag specified.
DisablePointerMethods bool
// DisablePointerAddresses specifies whether to disable the printing of
// pointer addresses. This is useful when diffing data structures in tests.
DisablePointerAddresses bool
// DisableCapacities specifies whether to disable the printing of capacities
// for arrays, slices, maps and channels. This is useful when diffing
// data structures in tests.
DisableCapacities bool
// ContinueOnMethod specifies whether or not recursion should continue once
// a custom error or Stringer interface is invoked. The default, false,
// means it will print the results of invoking the custom error or Stringer
// interface and return immediately instead of continuing to recurse into
// the internals of the data type.
//
// NOTE: This flag does not have any effect if method invocation is disabled
// via the DisableMethods or DisablePointerMethods options.
ContinueOnMethod bool
// SortKeys specifies map keys should be sorted before being printed. Use
// this to have a more deterministic, diffable output. Note that only
// native types (bool, int, uint, floats, uintptr and string) and types
// that support the error or Stringer interfaces (if methods are
// enabled) are supported, with other types sorted according to the
// reflect.Value.String() output which guarantees display stability.
SortKeys bool
// SpewKeys specifies that, as a last resort attempt, map keys should
// be spewed to strings and sorted by those strings. This is only
// considered if SortKeys is true.
SpewKeys bool
}
// Config is the active configuration of the top-level functions.
// The configuration can be changed by modifying the contents of spew.Config.
var Config = ConfigState{Indent: " "}
// Errorf is a wrapper for fmt.Errorf that treats each argument as if it were
// passed with a Formatter interface returned by c.NewFormatter. It returns
// the formatted string as a value that satisfies error. See NewFormatter
// for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Errorf(format, c.NewFormatter(a), c.NewFormatter(b))
func (c *ConfigState) Errorf(format string, a ...interface{}) (err error) {
return fmt.Errorf(format, c.convertArgs(a)...)
}
// Fprint is a wrapper for fmt.Fprint that treats each argument as if it were
// passed with a Formatter interface returned by c.NewFormatter. It returns
// the number of bytes written and any write error encountered. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Fprint(w, c.NewFormatter(a), c.NewFormatter(b))
func (c *ConfigState) Fprint(w io.Writer, a ...interface{}) (n int, err error) {
return fmt.Fprint(w, c.convertArgs(a)...)
}
// Fprintf is a wrapper for fmt.Fprintf that treats each argument as if it were
// passed with a Formatter interface returned by c.NewFormatter. It returns
// the number of bytes written and any write error encountered. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Fprintf(w, format, c.NewFormatter(a), c.NewFormatter(b))
func (c *ConfigState) Fprintf(w io.Writer, format string, a ...interface{}) (n int, err error) {
return fmt.Fprintf(w, format, c.convertArgs(a)...)
}
// Fprintln is a wrapper for fmt.Fprintln that treats each argument as if it
// passed with a Formatter interface returned by c.NewFormatter. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Fprintln(w, c.NewFormatter(a), c.NewFormatter(b))
func (c *ConfigState) Fprintln(w io.Writer, a ...interface{}) (n int, err error) {
return fmt.Fprintln(w, c.convertArgs(a)...)
}
// Print is a wrapper for fmt.Print that treats each argument as if it were
// passed with a Formatter interface returned by c.NewFormatter. It returns
// the number of bytes written and any write error encountered. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Print(c.NewFormatter(a), c.NewFormatter(b))
func (c *ConfigState) Print(a ...interface{}) (n int, err error) {
return fmt.Print(c.convertArgs(a)...)
}
// Printf is a wrapper for fmt.Printf that treats each argument as if it were
// passed with a Formatter interface returned by c.NewFormatter. It returns
// the number of bytes written and any write error encountered. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Printf(format, c.NewFormatter(a), c.NewFormatter(b))
func (c *ConfigState) Printf(format string, a ...interface{}) (n int, err error) {
return fmt.Printf(format, c.convertArgs(a)...)
}
// Println is a wrapper for fmt.Println that treats each argument as if it were
// passed with a Formatter interface returned by c.NewFormatter. It returns
// the number of bytes written and any write error encountered. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Println(c.NewFormatter(a), c.NewFormatter(b))
func (c *ConfigState) Println(a ...interface{}) (n int, err error) {
return fmt.Println(c.convertArgs(a)...)
}
// Sprint is a wrapper for fmt.Sprint that treats each argument as if it were
// passed with a Formatter interface returned by c.NewFormatter. It returns
// the resulting string. See NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Sprint(c.NewFormatter(a), c.NewFormatter(b))
func (c *ConfigState) Sprint(a ...interface{}) string {
return fmt.Sprint(c.convertArgs(a)...)
}
// Sprintf is a wrapper for fmt.Sprintf that treats each argument as if it were
// passed with a Formatter interface returned by c.NewFormatter. It returns
// the resulting string. See NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Sprintf(format, c.NewFormatter(a), c.NewFormatter(b))
func (c *ConfigState) Sprintf(format string, a ...interface{}) string {
return fmt.Sprintf(format, c.convertArgs(a)...)
}
// Sprintln is a wrapper for fmt.Sprintln that treats each argument as if it
// were passed with a Formatter interface returned by c.NewFormatter. It
// returns the resulting string. See NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Sprintln(c.NewFormatter(a), c.NewFormatter(b))
func (c *ConfigState) Sprintln(a ...interface{}) string {
return fmt.Sprintln(c.convertArgs(a)...)
}
/*
NewFormatter returns a custom formatter that satisfies the fmt.Formatter
interface. As a result, it integrates cleanly with standard fmt package
printing functions. The formatter is useful for inline printing of smaller data
types similar to the standard %v format specifier.
The custom formatter only responds to the %v (most compact), %+v (adds pointer
addresses), %#v (adds types), and %#+v (adds types and pointer addresses) verb
combinations. Any other verbs such as %x and %q will be sent to the the
standard fmt package for formatting. In addition, the custom formatter ignores
the width and precision arguments (however they will still work on the format
specifiers not handled by the custom formatter).
Typically this function shouldn't be called directly. It is much easier to make
use of the custom formatter by calling one of the convenience functions such as
c.Printf, c.Println, or c.Printf.
*/
func (c *ConfigState) NewFormatter(v interface{}) fmt.Formatter {
return newFormatter(c, v)
}
// Fdump formats and displays the passed arguments to io.Writer w. It formats
// exactly the same as Dump.
func (c *ConfigState) Fdump(w io.Writer, a ...interface{}) {
fdump(c, w, a...)
}
/*
Dump displays the passed parameters to standard out with newlines, customizable
indentation, and additional debug information such as complete types and all
pointer addresses used to indirect to the final value. It provides the
following features over the built-in printing facilities provided by the fmt
package:
* Pointers are dereferenced and followed
* Circular data structures are detected and handled properly
* Custom Stringer/error interfaces are optionally invoked, including
on unexported types
* Custom types which only implement the Stringer/error interfaces via
a pointer receiver are optionally invoked when passing non-pointer
variables
* Byte arrays and slices are dumped like the hexdump -C command which
includes offsets, byte values in hex, and ASCII output
The configuration options are controlled by modifying the public members
of c. See ConfigState for options documentation.
See Fdump if you would prefer dumping to an arbitrary io.Writer or Sdump to
get the formatted result as a string.
*/
func (c *ConfigState) Dump(a ...interface{}) {
fdump(c, os.Stdout, a...)
}
// Sdump returns a string with the passed arguments formatted exactly the same
// as Dump.
func (c *ConfigState) Sdump(a ...interface{}) string {
var buf bytes.Buffer
fdump(c, &buf, a...)
return buf.String()
}
// convertArgs accepts a slice of arguments and returns a slice of the same
// length with each argument converted to a spew Formatter interface using
// the ConfigState associated with s.
func (c *ConfigState) convertArgs(args []interface{}) (formatters []interface{}) {
formatters = make([]interface{}, len(args))
for index, arg := range args {
formatters[index] = newFormatter(c, arg)
}
return formatters
}
// NewDefaultConfig returns a ConfigState with the following default settings.
//
// Indent: " "
// MaxDepth: 0
// DisableMethods: false
// DisablePointerMethods: false
// ContinueOnMethod: false
// SortKeys: false
func NewDefaultConfig() *ConfigState {
return &ConfigState{Indent: " "}
}
vendor/github.com/davecgh/go-spew/spew/doc.go
Generated Vendored
+211
View File
@@ -0,0 +1,211 @@
/*
* Copyright (c) 2013-2016 Dave Collins <dave@davec.name>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
Package spew implements a deep pretty printer for Go data structures to aid in
debugging.
A quick overview of the additional features spew provides over the built-in
printing facilities for Go data types are as follows:
* Pointers are dereferenced and followed
* Circular data structures are detected and handled properly
* Custom Stringer/error interfaces are optionally invoked, including
on unexported types
* Custom types which only implement the Stringer/error interfaces via
a pointer receiver are optionally invoked when passing non-pointer
variables
* Byte arrays and slices are dumped like the hexdump -C command which
includes offsets, byte values in hex, and ASCII output (only when using
Dump style)
There are two different approaches spew allows for dumping Go data structures:
* Dump style which prints with newlines, customizable indentation,
and additional debug information such as types and all pointer addresses
used to indirect to the final value
* A custom Formatter interface that integrates cleanly with the standard fmt
package and replaces %v, %+v, %#v, and %#+v to provide inline printing
similar to the default %v while providing the additional functionality
outlined above and passing unsupported format verbs such as %x and %q
along to fmt
Quick Start
This section demonstrates how to quickly get started with spew. See the
sections below for further details on formatting and configuration options.
To dump a variable with full newlines, indentation, type, and pointer
information use Dump, Fdump, or Sdump:
spew.Dump(myVar1, myVar2, ...)
spew.Fdump(someWriter, myVar1, myVar2, ...)
str := spew.Sdump(myVar1, myVar2, ...)
Alternatively, if you would prefer to use format strings with a compacted inline
printing style, use the convenience wrappers Printf, Fprintf, etc with
%v (most compact), %+v (adds pointer addresses), %#v (adds types), or
%#+v (adds types and pointer addresses):
spew.Printf("myVar1: %v -- myVar2: %+v", myVar1, myVar2)
spew.Printf("myVar3: %#v -- myVar4: %#+v", myVar3, myVar4)
spew.Fprintf(someWriter, "myVar1: %v -- myVar2: %+v", myVar1, myVar2)
spew.Fprintf(someWriter, "myVar3: %#v -- myVar4: %#+v", myVar3, myVar4)
Configuration Options
Configuration of spew is handled by fields in the ConfigState type. For
convenience, all of the top-level functions use a global state available
via the spew.Config global.
It is also possible to create a ConfigState instance that provides methods
equivalent to the top-level functions. This allows concurrent configuration
options. See the ConfigState documentation for more details.
The following configuration options are available:
* Indent
String to use for each indentation level for Dump functions.
It is a single space by default. A popular alternative is "\t".
* MaxDepth
Maximum number of levels to descend into nested data structures.
There is no limit by default.
* DisableMethods
Disables invocation of error and Stringer interface methods.
Method invocation is enabled by default.
* DisablePointerMethods
Disables invocation of error and Stringer interface methods on types
which only accept pointer receivers from non-pointer variables.
Pointer method invocation is enabled by default.
* DisablePointerAddresses
DisablePointerAddresses specifies whether to disable the printing of
pointer addresses. This is useful when diffing data structures in tests.
* DisableCapacities
DisableCapacities specifies whether to disable the printing of
capacities for arrays, slices, maps and channels. This is useful when
diffing data structures in tests.
* ContinueOnMethod
Enables recursion into types after invoking error and Stringer interface
methods. Recursion after method invocation is disabled by default.
* SortKeys
Specifies map keys should be sorted before being printed. Use
this to have a more deterministic, diffable output. Note that
only native types (bool, int, uint, floats, uintptr and string)
and types which implement error or Stringer interfaces are
supported with other types sorted according to the
reflect.Value.String() output which guarantees display
stability. Natural map order is used by default.
* SpewKeys
Specifies that, as a last resort attempt, map keys should be
spewed to strings and sorted by those strings. This is only
considered if SortKeys is true.
Dump Usage
Simply call spew.Dump with a list of variables you want to dump:
spew.Dump(myVar1, myVar2, ...)
You may also call spew.Fdump if you would prefer to output to an arbitrary
io.Writer. For example, to dump to standard error:
spew.Fdump(os.Stderr, myVar1, myVar2, ...)
A third option is to call spew.Sdump to get the formatted output as a string:
str := spew.Sdump(myVar1, myVar2, ...)
Sample Dump Output
See the Dump example for details on the setup of the types and variables being
shown here.
(main.Foo) {
unexportedField: (*main.Bar)(0xf84002e210)({
flag: (main.Flag) flagTwo,
data: (uintptr) <nil>
}),
ExportedField: (map[interface {}]interface {}) (len=1) {
(string) (len=3) "one": (bool) true
}
}
Byte (and uint8) arrays and slices are displayed uniquely like the hexdump -C
command as shown.
([]uint8) (len=32 cap=32) {
00000000 11 12 13 14 15 16 17 18 19 1a 1b 1c 1d 1e 1f 20 |............... |
00000010 21 22 23 24 25 26 27 28 29 2a 2b 2c 2d 2e 2f 30 |!"#$%&'()*+,-./0|
00000020 31 32 |12|
}
Custom Formatter
Spew provides a custom formatter that implements the fmt.Formatter interface
so that it integrates cleanly with standard fmt package printing functions. The
formatter is useful for inline printing of smaller data types similar to the
standard %v format specifier.
The custom formatter only responds to the %v (most compact), %+v (adds pointer
addresses), %#v (adds types), or %#+v (adds types and pointer addresses) verb
combinations. Any other verbs such as %x and %q will be sent to the the
standard fmt package for formatting. In addition, the custom formatter ignores
the width and precision arguments (however they will still work on the format
specifiers not handled by the custom formatter).
Custom Formatter Usage
The simplest way to make use of the spew custom formatter is to call one of the
convenience functions such as spew.Printf, spew.Println, or spew.Printf. The
functions have syntax you are most likely already familiar with:
spew.Printf("myVar1: %v -- myVar2: %+v", myVar1, myVar2)
spew.Printf("myVar3: %#v -- myVar4: %#+v", myVar3, myVar4)
spew.Println(myVar, myVar2)
spew.Fprintf(os.Stderr, "myVar1: %v -- myVar2: %+v", myVar1, myVar2)
spew.Fprintf(os.Stderr, "myVar3: %#v -- myVar4: %#+v", myVar3, myVar4)
See the Index for the full list convenience functions.
Sample Formatter Output
Double pointer to a uint8:
%v: <**>5
%+v: <**>(0xf8400420d0->0xf8400420c8)5
%#v: (**uint8)5
%#+v: (**uint8)(0xf8400420d0->0xf8400420c8)5
Pointer to circular struct with a uint8 field and a pointer to itself:
%v: <*>{1 <*><shown>}
%+v: <*>(0xf84003e260){ui8:1 c:<*>(0xf84003e260)<shown>}
%#v: (*main.circular){ui8:(uint8)1 c:(*main.circular)<shown>}
%#+v: (*main.circular)(0xf84003e260){ui8:(uint8)1 c:(*main.circular)(0xf84003e260)<shown>}
See the Printf example for details on the setup of variables being shown
here.
Errors
Since it is possible for custom Stringer/error interfaces to panic, spew
detects them and handles them internally by printing the panic information
inline with the output. Since spew is intended to provide deep pretty printing
capabilities on structures, it intentionally does not return any errors.
*/
package spew
vendor/github.com/davecgh/go-spew/spew/dump.go
Generated Vendored
+509
View File
@@ -0,0 +1,509 @@
/*
* Copyright (c) 2013-2016 Dave Collins <dave@davec.name>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
package spew
import (
"bytes"
"encoding/hex"
"fmt"
"io"
"os"
"reflect"
"regexp"
"strconv"
"strings"
)
var (
// uint8Type is a reflect.Type representing a uint8. It is used to
// convert cgo types to uint8 slices for hexdumping.
uint8Type = reflect.TypeOf(uint8(0))
// cCharRE is a regular expression that matches a cgo char.
// It is used to detect character arrays to hexdump them.
cCharRE = regexp.MustCompile("^.*\\._Ctype_char$")
// cUnsignedCharRE is a regular expression that matches a cgo unsigned
// char. It is used to detect unsigned character arrays to hexdump
// them.
cUnsignedCharRE = regexp.MustCompile("^.*\\._Ctype_unsignedchar$")
// cUint8tCharRE is a regular expression that matches a cgo uint8_t.
// It is used to detect uint8_t arrays to hexdump them.
cUint8tCharRE = regexp.MustCompile("^.*\\._Ctype_uint8_t$")
)
// dumpState contains information about the state of a dump operation.
type dumpState struct {
w io.Writer
depth int
pointers map[uintptr]int
ignoreNextType bool
ignoreNextIndent bool
cs *ConfigState
}
// indent performs indentation according to the depth level and cs.Indent
// option.
func (d *dumpState) indent() {
if d.ignoreNextIndent {
d.ignoreNextIndent = false
return
}
d.w.Write(bytes.Repeat([]byte(d.cs.Indent), d.depth))
}
// unpackValue returns values inside of non-nil interfaces when possible.
// This is useful for data types like structs, arrays, slices, and maps which
// can contain varying types packed inside an interface.
func (d *dumpState) unpackValue(v reflect.Value) reflect.Value {
if v.Kind() == reflect.Interface && !v.IsNil() {
v = v.Elem()
}
return v
}
// dumpPtr handles formatting of pointers by indirecting them as necessary.
func (d *dumpState) dumpPtr(v reflect.Value) {
// Remove pointers at or below the current depth from map used to detect
// circular refs.
for k, depth := range d.pointers {
if depth >= d.depth {
delete(d.pointers, k)
}
}
// Keep list of all dereferenced pointers to show later.
pointerChain := make([]uintptr, 0)
// Figure out how many levels of indirection there are by dereferencing
// pointers and unpacking interfaces down the chain while detecting circular
// references.
nilFound := false
cycleFound := false
indirects := 0
ve := v
for ve.Kind() == reflect.Ptr {
if ve.IsNil() {
nilFound = true
break
}
indirects++
addr := ve.Pointer()
pointerChain = append(pointerChain, addr)
if pd, ok := d.pointers[addr]; ok && pd < d.depth {
cycleFound = true
indirects--
break
}
d.pointers[addr] = d.depth
ve = ve.Elem()
if ve.Kind() == reflect.Interface {
if ve.IsNil() {
nilFound = true
break
}
ve = ve.Elem()
}
}
// Display type information.
d.w.Write(openParenBytes)
d.w.Write(bytes.Repeat(asteriskBytes, indirects))
d.w.Write([]byte(ve.Type().String()))
d.w.Write(closeParenBytes)
// Display pointer information.
if !d.cs.DisablePointerAddresses && len(pointerChain) > 0 {
d.w.Write(openParenBytes)
for i, addr := range pointerChain {
if i > 0 {
d.w.Write(pointerChainBytes)
}
printHexPtr(d.w, addr)
}
d.w.Write(closeParenBytes)
}
// Display dereferenced value.
d.w.Write(openParenBytes)
switch {
case nilFound == true:
d.w.Write(nilAngleBytes)
case cycleFound == true:
d.w.Write(circularBytes)
default:
d.ignoreNextType = true
d.dump(ve)
}
d.w.Write(closeParenBytes)
}
// dumpSlice handles formatting of arrays and slices. Byte (uint8 under
// reflection) arrays and slices are dumped in hexdump -C fashion.
func (d *dumpState) dumpSlice(v reflect.Value) {
// Determine whether this type should be hex dumped or not. Also,
// for types which should be hexdumped, try to use the underlying data
// first, then fall back to trying to convert them to a uint8 slice.
var buf []uint8
doConvert := false
doHexDump := false
numEntries := v.Len()
if numEntries > 0 {
vt := v.Index(0).Type()
vts := vt.String()
switch {
// C types that need to be converted.
case cCharRE.MatchString(vts):
fallthrough
case cUnsignedCharRE.MatchString(vts):
fallthrough
case cUint8tCharRE.MatchString(vts):
doConvert = true
// Try to use existing uint8 slices and fall back to converting
// and copying if that fails.
case vt.Kind() == reflect.Uint8:
// We need an addressable interface to convert the type
// to a byte slice. However, the reflect package won't
// give us an interface on certain things like
// unexported struct fields in order to enforce
// visibility rules. We use unsafe, when available, to
// bypass these restrictions since this package does not
// mutate the values.
vs := v
if !vs.CanInterface() || !vs.CanAddr() {
vs = unsafeReflectValue(vs)
}
if !UnsafeDisabled {
vs = vs.Slice(0, numEntries)
// Use the existing uint8 slice if it can be
// type asserted.
iface := vs.Interface()
if slice, ok := iface.([]uint8); ok {
buf = slice
doHexDump = true
break
}
}
// The underlying data needs to be converted if it can't
// be type asserted to a uint8 slice.
doConvert = true
}
// Copy and convert the underlying type if needed.
if doConvert && vt.ConvertibleTo(uint8Type) {
// Convert and copy each element into a uint8 byte
// slice.
buf = make([]uint8, numEntries)
for i := 0; i < numEntries; i++ {
vv := v.Index(i)
buf[i] = uint8(vv.Convert(uint8Type).Uint())
}
doHexDump = true
}
}
// Hexdump the entire slice as needed.
if doHexDump {
indent := strings.Repeat(d.cs.Indent, d.depth)
str := indent + hex.Dump(buf)
str = strings.Replace(str, "\n", "\n"+indent, -1)
str = strings.TrimRight(str, d.cs.Indent)
d.w.Write([]byte(str))
return
}
// Recursively call dump for each item.
for i := 0; i < numEntries; i++ {
d.dump(d.unpackValue(v.Index(i)))
if i < (numEntries - 1) {
d.w.Write(commaNewlineBytes)
} else {
d.w.Write(newlineBytes)
}
}
}
// dump is the main workhorse for dumping a value. It uses the passed reflect
// value to figure out what kind of object we are dealing with and formats it
// appropriately. It is a recursive function, however circular data structures
// are detected and handled properly.
func (d *dumpState) dump(v reflect.Value) {
// Handle invalid reflect values immediately.
kind := v.Kind()
if kind == reflect.Invalid {
d.w.Write(invalidAngleBytes)
return
}
// Handle pointers specially.
if kind == reflect.Ptr {
d.indent()
d.dumpPtr(v)
return
}
// Print type information unless already handled elsewhere.
if !d.ignoreNextType {
d.indent()
d.w.Write(openParenBytes)
d.w.Write([]byte(v.Type().String()))
d.w.Write(closeParenBytes)
d.w.Write(spaceBytes)
}
d.ignoreNextType = false
// Display length and capacity if the built-in len and cap functions
// work with the value's kind and the len/cap itself is non-zero.
valueLen, valueCap := 0, 0
switch v.Kind() {
case reflect.Array, reflect.Slice, reflect.Chan:
valueLen, valueCap = v.Len(), v.Cap()
case reflect.Map, reflect.String:
valueLen = v.Len()
}
if valueLen != 0 || !d.cs.DisableCapacities && valueCap != 0 {
d.w.Write(openParenBytes)
if valueLen != 0 {
d.w.Write(lenEqualsBytes)
printInt(d.w, int64(valueLen), 10)
}
if !d.cs.DisableCapacities && valueCap != 0 {
if valueLen != 0 {
d.w.Write(spaceBytes)
}
d.w.Write(capEqualsBytes)
printInt(d.w, int64(valueCap), 10)
}
d.w.Write(closeParenBytes)
d.w.Write(spaceBytes)
}
// Call Stringer/error interfaces if they exist and the handle methods flag
// is enabled
if !d.cs.DisableMethods {
if (kind != reflect.Invalid) && (kind != reflect.Interface) {
if handled := handleMethods(d.cs, d.w, v); handled {
return
}
}
}
switch kind {
case reflect.Invalid:
// Do nothing. We should never get here since invalid has already
// been handled above.
case reflect.Bool:
printBool(d.w, v.Bool())
case reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Int:
printInt(d.w, v.Int(), 10)
case reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uint:
printUint(d.w, v.Uint(), 10)
case reflect.Float32:
printFloat(d.w, v.Float(), 32)
case reflect.Float64:
printFloat(d.w, v.Float(), 64)
case reflect.Complex64:
printComplex(d.w, v.Complex(), 32)
case reflect.Complex128:
printComplex(d.w, v.Complex(), 64)
case reflect.Slice:
if v.IsNil() {
d.w.Write(nilAngleBytes)
break
}
fallthrough
case reflect.Array:
d.w.Write(openBraceNewlineBytes)
d.depth++
if (d.cs.MaxDepth != 0) && (d.depth > d.cs.MaxDepth) {
d.indent()
d.w.Write(maxNewlineBytes)
} else {
d.dumpSlice(v)
}
d.depth--
d.indent()
d.w.Write(closeBraceBytes)
case reflect.String:
d.w.Write([]byte(strconv.Quote(v.String())))
case reflect.Interface:
// The only time we should get here is for nil interfaces due to
// unpackValue calls.
if v.IsNil() {
d.w.Write(nilAngleBytes)
}
case reflect.Ptr:
// Do nothing. We should never get here since pointers have already
// been handled above.
case reflect.Map:
// nil maps should be indicated as different than empty maps
if v.IsNil() {
d.w.Write(nilAngleBytes)
break
}
d.w.Write(openBraceNewlineBytes)
d.depth++
if (d.cs.MaxDepth != 0) && (d.depth > d.cs.MaxDepth) {
d.indent()
d.w.Write(maxNewlineBytes)
} else {
numEntries := v.Len()
keys := v.MapKeys()
if d.cs.SortKeys {
sortValues(keys, d.cs)
}
for i, key := range keys {
d.dump(d.unpackValue(key))
d.w.Write(colonSpaceBytes)
d.ignoreNextIndent = true
d.dump(d.unpackValue(v.MapIndex(key)))
if i < (numEntries - 1) {
d.w.Write(commaNewlineBytes)
} else {
d.w.Write(newlineBytes)
}
}
}
d.depth--
d.indent()
d.w.Write(closeBraceBytes)
case reflect.Struct:
d.w.Write(openBraceNewlineBytes)
d.depth++
if (d.cs.MaxDepth != 0) && (d.depth > d.cs.MaxDepth) {
d.indent()
d.w.Write(maxNewlineBytes)
} else {
vt := v.Type()
numFields := v.NumField()
for i := 0; i < numFields; i++ {
d.indent()
vtf := vt.Field(i)
d.w.Write([]byte(vtf.Name))
d.w.Write(colonSpaceBytes)
d.ignoreNextIndent = true
d.dump(d.unpackValue(v.Field(i)))
if i < (numFields - 1) {
d.w.Write(commaNewlineBytes)
} else {
d.w.Write(newlineBytes)
}
}
}
d.depth--
d.indent()
d.w.Write(closeBraceBytes)
case reflect.Uintptr:
printHexPtr(d.w, uintptr(v.Uint()))
case reflect.UnsafePointer, reflect.Chan, reflect.Func:
printHexPtr(d.w, v.Pointer())
// There were not any other types at the time this code was written, but
// fall back to letting the default fmt package handle it in case any new
// types are added.
default:
if v.CanInterface() {
fmt.Fprintf(d.w, "%v", v.Interface())
} else {
fmt.Fprintf(d.w, "%v", v.String())
}
}
}
// fdump is a helper function to consolidate the logic from the various public
// methods which take varying writers and config states.
func fdump(cs *ConfigState, w io.Writer, a ...interface{}) {
for _, arg := range a {
if arg == nil {
w.Write(interfaceBytes)
w.Write(spaceBytes)
w.Write(nilAngleBytes)
w.Write(newlineBytes)
continue
}
d := dumpState{w: w, cs: cs}
d.pointers = make(map[uintptr]int)
d.dump(reflect.ValueOf(arg))
d.w.Write(newlineBytes)
}
}
// Fdump formats and displays the passed arguments to io.Writer w. It formats
// exactly the same as Dump.
func Fdump(w io.Writer, a ...interface{}) {
fdump(&Config, w, a...)
}
// Sdump returns a string with the passed arguments formatted exactly the same
// as Dump.
func Sdump(a ...interface{}) string {
var buf bytes.Buffer
fdump(&Config, &buf, a...)
return buf.String()
}
/*
Dump displays the passed parameters to standard out with newlines, customizable
indentation, and additional debug information such as complete types and all
pointer addresses used to indirect to the final value. It provides the
following features over the built-in printing facilities provided by the fmt
package:
* Pointers are dereferenced and followed
* Circular data structures are detected and handled properly
* Custom Stringer/error interfaces are optionally invoked, including
on unexported types
* Custom types which only implement the Stringer/error interfaces via
a pointer receiver are optionally invoked when passing non-pointer
variables
* Byte arrays and slices are dumped like the hexdump -C command which
includes offsets, byte values in hex, and ASCII output
The configuration options are controlled by an exported package global,
spew.Config. See ConfigState for options documentation.
See Fdump if you would prefer dumping to an arbitrary io.Writer or Sdump to
get the formatted result as a string.
*/
func Dump(a ...interface{}) {
fdump(&Config, os.Stdout, a...)
}
vendor/github.com/davecgh/go-spew/spew/format.go
Generated Vendored
+419
View File
@@ -0,0 +1,419 @@
/*
* Copyright (c) 2013-2016 Dave Collins <dave@davec.name>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
package spew
import (
"bytes"
"fmt"
"reflect"
"strconv"
"strings"
)
// supportedFlags is a list of all the character flags supported by fmt package.
const supportedFlags = "0-+# "
// formatState implements the fmt.Formatter interface and contains information
// about the state of a formatting operation. The NewFormatter function can
// be used to get a new Formatter which can be used directly as arguments
// in standard fmt package printing calls.
type formatState struct {
value interface{}
fs fmt.State
depth int
pointers map[uintptr]int
ignoreNextType bool
cs *ConfigState
}
// buildDefaultFormat recreates the original format string without precision
// and width information to pass in to fmt.Sprintf in the case of an
// unrecognized type. Unless new types are added to the language, this
// function won't ever be called.
func (f *formatState) buildDefaultFormat() (format string) {
buf := bytes.NewBuffer(percentBytes)
for _, flag := range supportedFlags {
if f.fs.Flag(int(flag)) {
buf.WriteRune(flag)
}
}
buf.WriteRune('v')
format = buf.String()
return format
}
// constructOrigFormat recreates the original format string including precision
// and width information to pass along to the standard fmt package. This allows
// automatic deferral of all format strings this package doesn't support.
func (f *formatState) constructOrigFormat(verb rune) (format string) {
buf := bytes.NewBuffer(percentBytes)
for _, flag := range supportedFlags {
if f.fs.Flag(int(flag)) {
buf.WriteRune(flag)
}
}
if width, ok := f.fs.Width(); ok {
buf.WriteString(strconv.Itoa(width))
}
if precision, ok := f.fs.Precision(); ok {
buf.Write(precisionBytes)
buf.WriteString(strconv.Itoa(precision))
}
buf.WriteRune(verb)
format = buf.String()
return format
}
// unpackValue returns values inside of non-nil interfaces when possible and
// ensures that types for values which have been unpacked from an interface
// are displayed when the show types flag is also set.
// This is useful for data types like structs, arrays, slices, and maps which
// can contain varying types packed inside an interface.
func (f *formatState) unpackValue(v reflect.Value) reflect.Value {
if v.Kind() == reflect.Interface {
f.ignoreNextType = false
if !v.IsNil() {
v = v.Elem()
}
}
return v
}
// formatPtr handles formatting of pointers by indirecting them as necessary.
func (f *formatState) formatPtr(v reflect.Value) {
// Display nil if top level pointer is nil.
showTypes := f.fs.Flag('#')
if v.IsNil() && (!showTypes || f.ignoreNextType) {
f.fs.Write(nilAngleBytes)
return
}
// Remove pointers at or below the current depth from map used to detect
// circular refs.
for k, depth := range f.pointers {
if depth >= f.depth {
delete(f.pointers, k)
}
}
// Keep list of all dereferenced pointers to possibly show later.
pointerChain := make([]uintptr, 0)
// Figure out how many levels of indirection there are by derferencing
// pointers and unpacking interfaces down the chain while detecting circular
// references.
nilFound := false
cycleFound := false
indirects := 0
ve := v
for ve.Kind() == reflect.Ptr {
if ve.IsNil() {
nilFound = true
break
}
indirects++
addr := ve.Pointer()
pointerChain = append(pointerChain, addr)
if pd, ok := f.pointers[addr]; ok && pd < f.depth {
cycleFound = true
indirects--
break
}
f.pointers[addr] = f.depth
ve = ve.Elem()
if ve.Kind() == reflect.Interface {
if ve.IsNil() {
nilFound = true
break
}
ve = ve.Elem()
}
}
// Display type or indirection level depending on flags.
if showTypes && !f.ignoreNextType {
f.fs.Write(openParenBytes)
f.fs.Write(bytes.Repeat(asteriskBytes, indirects))
f.fs.Write([]byte(ve.Type().String()))
f.fs.Write(closeParenBytes)
} else {
if nilFound || cycleFound {
indirects += strings.Count(ve.Type().String(), "*")
}
f.fs.Write(openAngleBytes)
f.fs.Write([]byte(strings.Repeat("*", indirects)))
f.fs.Write(closeAngleBytes)
}
// Display pointer information depending on flags.
if f.fs.Flag('+') && (len(pointerChain) > 0) {
f.fs.Write(openParenBytes)
for i, addr := range pointerChain {
if i > 0 {
f.fs.Write(pointerChainBytes)
}
printHexPtr(f.fs, addr)
}
f.fs.Write(closeParenBytes)
}
// Display dereferenced value.
switch {
case nilFound == true:
f.fs.Write(nilAngleBytes)
case cycleFound == true:
f.fs.Write(circularShortBytes)
default:
f.ignoreNextType = true
f.format(ve)
}
}
// format is the main workhorse for providing the Formatter interface. It
// uses the passed reflect value to figure out what kind of object we are
// dealing with and formats it appropriately. It is a recursive function,
// however circular data structures are detected and handled properly.
func (f *formatState) format(v reflect.Value) {
// Handle invalid reflect values immediately.
kind := v.Kind()
if kind == reflect.Invalid {
f.fs.Write(invalidAngleBytes)
return
}
// Handle pointers specially.
if kind == reflect.Ptr {
f.formatPtr(v)
return
}
// Print type information unless already handled elsewhere.
if !f.ignoreNextType && f.fs.Flag('#') {
f.fs.Write(openParenBytes)
f.fs.Write([]byte(v.Type().String()))
f.fs.Write(closeParenBytes)
}
f.ignoreNextType = false
// Call Stringer/error interfaces if they exist and the handle methods
// flag is enabled.
if !f.cs.DisableMethods {
if (kind != reflect.Invalid) && (kind != reflect.Interface) {
if handled := handleMethods(f.cs, f.fs, v); handled {
return
}
}
}
switch kind {
case reflect.Invalid:
// Do nothing. We should never get here since invalid has already
// been handled above.
case reflect.Bool:
printBool(f.fs, v.Bool())
case reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64, reflect.Int:
printInt(f.fs, v.Int(), 10)
case reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64, reflect.Uint:
printUint(f.fs, v.Uint(), 10)
case reflect.Float32:
printFloat(f.fs, v.Float(), 32)
case reflect.Float64:
printFloat(f.fs, v.Float(), 64)
case reflect.Complex64:
printComplex(f.fs, v.Complex(), 32)
case reflect.Complex128:
printComplex(f.fs, v.Complex(), 64)
case reflect.Slice:
if v.IsNil() {
f.fs.Write(nilAngleBytes)
break
}
fallthrough
case reflect.Array:
f.fs.Write(openBracketBytes)
f.depth++
if (f.cs.MaxDepth != 0) && (f.depth > f.cs.MaxDepth) {
f.fs.Write(maxShortBytes)
} else {
numEntries := v.Len()
for i := 0; i < numEntries; i++ {
if i > 0 {
f.fs.Write(spaceBytes)
}
f.ignoreNextType = true
f.format(f.unpackValue(v.Index(i)))
}
}
f.depth--
f.fs.Write(closeBracketBytes)
case reflect.String:
f.fs.Write([]byte(v.String()))
case reflect.Interface:
// The only time we should get here is for nil interfaces due to
// unpackValue calls.
if v.IsNil() {
f.fs.Write(nilAngleBytes)
}
case reflect.Ptr:
// Do nothing. We should never get here since pointers have already
// been handled above.
case reflect.Map:
// nil maps should be indicated as different than empty maps
if v.IsNil() {
f.fs.Write(nilAngleBytes)
break
}
f.fs.Write(openMapBytes)
f.depth++
if (f.cs.MaxDepth != 0) && (f.depth > f.cs.MaxDepth) {
f.fs.Write(maxShortBytes)
} else {
keys := v.MapKeys()
if f.cs.SortKeys {
sortValues(keys, f.cs)
}
for i, key := range keys {
if i > 0 {
f.fs.Write(spaceBytes)
}
f.ignoreNextType = true
f.format(f.unpackValue(key))
f.fs.Write(colonBytes)
f.ignoreNextType = true
f.format(f.unpackValue(v.MapIndex(key)))
}
}
f.depth--
f.fs.Write(closeMapBytes)
case reflect.Struct:
numFields := v.NumField()
f.fs.Write(openBraceBytes)
f.depth++
if (f.cs.MaxDepth != 0) && (f.depth > f.cs.MaxDepth) {
f.fs.Write(maxShortBytes)
} else {
vt := v.Type()
for i := 0; i < numFields; i++ {
if i > 0 {
f.fs.Write(spaceBytes)
}
vtf := vt.Field(i)
if f.fs.Flag('+') || f.fs.Flag('#') {
f.fs.Write([]byte(vtf.Name))
f.fs.Write(colonBytes)
}
f.format(f.unpackValue(v.Field(i)))
}
}
f.depth--
f.fs.Write(closeBraceBytes)
case reflect.Uintptr:
printHexPtr(f.fs, uintptr(v.Uint()))
case reflect.UnsafePointer, reflect.Chan, reflect.Func:
printHexPtr(f.fs, v.Pointer())
// There were not any other types at the time this code was written, but
// fall back to letting the default fmt package handle it if any get added.
default:
format := f.buildDefaultFormat()
if v.CanInterface() {
fmt.Fprintf(f.fs, format, v.Interface())
} else {
fmt.Fprintf(f.fs, format, v.String())
}
}
}
// Format satisfies the fmt.Formatter interface. See NewFormatter for usage
// details.
func (f *formatState) Format(fs fmt.State, verb rune) {
f.fs = fs
// Use standard formatting for verbs that are not v.
if verb != 'v' {
format := f.constructOrigFormat(verb)
fmt.Fprintf(fs, format, f.value)
return
}
if f.value == nil {
if fs.Flag('#') {
fs.Write(interfaceBytes)
}
fs.Write(nilAngleBytes)
return
}
f.format(reflect.ValueOf(f.value))
}
// newFormatter is a helper function to consolidate the logic from the various
// public methods which take varying config states.
func newFormatter(cs *ConfigState, v interface{}) fmt.Formatter {
fs := &formatState{value: v, cs: cs}
fs.pointers = make(map[uintptr]int)
return fs
}
/*
NewFormatter returns a custom formatter that satisfies the fmt.Formatter
interface. As a result, it integrates cleanly with standard fmt package
printing functions. The formatter is useful for inline printing of smaller data
types similar to the standard %v format specifier.
The custom formatter only responds to the %v (most compact), %+v (adds pointer
addresses), %#v (adds types), or %#+v (adds types and pointer addresses) verb
combinations. Any other verbs such as %x and %q will be sent to the the
standard fmt package for formatting. In addition, the custom formatter ignores
the width and precision arguments (however they will still work on the format
specifiers not handled by the custom formatter).
Typically this function shouldn't be called directly. It is much easier to make
use of the custom formatter by calling one of the convenience functions such as
Printf, Println, or Fprintf.
*/
func NewFormatter(v interface{}) fmt.Formatter {
return newFormatter(&Config, v)
}
vendor/github.com/davecgh/go-spew/spew/spew.go
Generated Vendored
+148
View File
@@ -0,0 +1,148 @@
/*
* Copyright (c) 2013-2016 Dave Collins <dave@davec.name>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
package spew
import (
"fmt"
"io"
)
// Errorf is a wrapper for fmt.Errorf that treats each argument as if it were
// passed with a default Formatter interface returned by NewFormatter. It
// returns the formatted string as a value that satisfies error. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Errorf(format, spew.NewFormatter(a), spew.NewFormatter(b))
func Errorf(format string, a ...interface{}) (err error) {
return fmt.Errorf(format, convertArgs(a)...)
}
// Fprint is a wrapper for fmt.Fprint that treats each argument as if it were
// passed with a default Formatter interface returned by NewFormatter. It
// returns the number of bytes written and any write error encountered. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Fprint(w, spew.NewFormatter(a), spew.NewFormatter(b))
func Fprint(w io.Writer, a ...interface{}) (n int, err error) {
return fmt.Fprint(w, convertArgs(a)...)
}
// Fprintf is a wrapper for fmt.Fprintf that treats each argument as if it were
// passed with a default Formatter interface returned by NewFormatter. It
// returns the number of bytes written and any write error encountered. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Fprintf(w, format, spew.NewFormatter(a), spew.NewFormatter(b))
func Fprintf(w io.Writer, format string, a ...interface{}) (n int, err error) {
return fmt.Fprintf(w, format, convertArgs(a)...)
}
// Fprintln is a wrapper for fmt.Fprintln that treats each argument as if it
// passed with a default Formatter interface returned by NewFormatter. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Fprintln(w, spew.NewFormatter(a), spew.NewFormatter(b))
func Fprintln(w io.Writer, a ...interface{}) (n int, err error) {
return fmt.Fprintln(w, convertArgs(a)...)
}
// Print is a wrapper for fmt.Print that treats each argument as if it were
// passed with a default Formatter interface returned by NewFormatter. It
// returns the number of bytes written and any write error encountered. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Print(spew.NewFormatter(a), spew.NewFormatter(b))
func Print(a ...interface{}) (n int, err error) {
return fmt.Print(convertArgs(a)...)
}
// Printf is a wrapper for fmt.Printf that treats each argument as if it were
// passed with a default Formatter interface returned by NewFormatter. It
// returns the number of bytes written and any write error encountered. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Printf(format, spew.NewFormatter(a), spew.NewFormatter(b))
func Printf(format string, a ...interface{}) (n int, err error) {
return fmt.Printf(format, convertArgs(a)...)
}
// Println is a wrapper for fmt.Println that treats each argument as if it were
// passed with a default Formatter interface returned by NewFormatter. It
// returns the number of bytes written and any write error encountered. See
// NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Println(spew.NewFormatter(a), spew.NewFormatter(b))
func Println(a ...interface{}) (n int, err error) {
return fmt.Println(convertArgs(a)...)
}
// Sprint is a wrapper for fmt.Sprint that treats each argument as if it were
// passed with a default Formatter interface returned by NewFormatter. It
// returns the resulting string. See NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Sprint(spew.NewFormatter(a), spew.NewFormatter(b))
func Sprint(a ...interface{}) string {
return fmt.Sprint(convertArgs(a)...)
}
// Sprintf is a wrapper for fmt.Sprintf that treats each argument as if it were
// passed with a default Formatter interface returned by NewFormatter. It
// returns the resulting string. See NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Sprintf(format, spew.NewFormatter(a), spew.NewFormatter(b))
func Sprintf(format string, a ...interface{}) string {
return fmt.Sprintf(format, convertArgs(a)...)
}
// Sprintln is a wrapper for fmt.Sprintln that treats each argument as if it
// were passed with a default Formatter interface returned by NewFormatter. It
// returns the resulting string. See NewFormatter for formatting details.
//
// This function is shorthand for the following syntax:
//
// fmt.Sprintln(spew.NewFormatter(a), spew.NewFormatter(b))
func Sprintln(a ...interface{}) string {
return fmt.Sprintln(convertArgs(a)...)
}
// convertArgs accepts a slice of arguments and returns a slice of the same
// length with each argument converted to a default spew Formatter interface.
func convertArgs(args []interface{}) (formatters []interface{}) {
formatters = make([]interface{}, len(args))
for index, arg := range args {
formatters[index] = NewFormatter(arg)
}
return formatters
}
vendor/github.com/eapache/go-resiliency/LICENSE
Generated Vendored
+22
View File
@@ -0,0 +1,22 @@
The MIT License (MIT)
Copyright (c) 2014 Evan Huus
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
vendor/github.com/eapache/go-resiliency/breaker/README.md
Generated Vendored
+34
View File
@@ -0,0 +1,34 @@
circuit-breaker
===============
[![Build Status](https://travis-ci.org/eapache/go-resiliency.svg?branch=master)](https://travis-ci.org/eapache/go-resiliency)
[![GoDoc](https://godoc.org/github.com/eapache/go-resiliency/breaker?status.svg)](https://godoc.org/github.com/eapache/go-resiliency/breaker)
[![Code of Conduct](https://img.shields.io/badge/code%20of%20conduct-active-blue.svg)](https://eapache.github.io/conduct.html)
The circuit-breaker resiliency pattern for golang.
Creating a breaker takes three parameters:
- error threshold (for opening the breaker)
- success threshold (for closing the breaker)
- timeout (how long to keep the breaker open)
```go
b := breaker.New(3, 1, 5*time.Second)
for {
result := b.Run(func() error {
// communicate with some external service and
// return an error if the communication failed
return nil
})
switch result {
case nil:
// success!
case breaker.ErrBreakerOpen:
// our function wasn't run because the breaker was open
default:
// some other error
}
}
```
vendor/github.com/eapache/go-resiliency/breaker/breaker.go
Generated Vendored
+161
View File
@@ -0,0 +1,161 @@
// Package breaker implements the circuit-breaker resiliency pattern for Go.
package breaker
import (
"errors"
"sync"
"sync/atomic"
"time"
)
// ErrBreakerOpen is the error returned from Run() when the function is not executed
// because the breaker is currently open.
var ErrBreakerOpen = errors.New("circuit breaker is open")
const (
closed uint32 = iota
open
halfOpen
)
// Breaker implements the circuit-breaker resiliency pattern
type Breaker struct {
errorThreshold, successThreshold int
timeout time.Duration
lock sync.Mutex
state uint32
errors, successes int
lastError time.Time
}
// New constructs a new circuit-breaker that starts closed.
// From closed, the breaker opens if "errorThreshold" errors are seen
// without an error-free period of at least "timeout". From open, the
// breaker half-closes after "timeout". From half-open, the breaker closes
// after "successThreshold" consecutive successes, or opens on a single error.
func New(errorThreshold, successThreshold int, timeout time.Duration) *Breaker {
return &Breaker{
errorThreshold: errorThreshold,
successThreshold: successThreshold,
timeout: timeout,
}
}
// Run will either return ErrBreakerOpen immediately if the circuit-breaker is
// already open, or it will run the given function and pass along its return
// value. It is safe to call Run concurrently on the same Breaker.
func (b *Breaker) Run(work func() error) error {
state := atomic.LoadUint32(&b.state)
if state == open {
return ErrBreakerOpen
}
return b.doWork(state, work)
}
// Go will either return ErrBreakerOpen immediately if the circuit-breaker is
// already open, or it will run the given function in a separate goroutine.
// If the function is run, Go will return nil immediately, and will *not* return
// the return value of the function. It is safe to call Go concurrently on the
// same Breaker.
func (b *Breaker) Go(work func() error) error {
state := atomic.LoadUint32(&b.state)
if state == open {
return ErrBreakerOpen
}
// errcheck complains about ignoring the error return value, but
// that's on purpose; if you want an error from a goroutine you have to
// get it over a channel or something
go b.doWork(state, work)
return nil
}
func (b *Breaker) doWork(state uint32, work func() error) error {
var panicValue interface{}
result := func() error {
defer func() {
panicValue = recover()
}()
return work()
}()
if result == nil && panicValue == nil && state == closed {
// short-circuit the normal, success path without contending
// on the lock
return nil
}
// oh well, I guess we have to contend on the lock
b.processResult(result, panicValue)
if panicValue != nil {
// as close as Go lets us come to a "rethrow" although unfortunately
// we lose the original panicing location
panic(panicValue)
}
return result
}
func (b *Breaker) processResult(result error, panicValue interface{}) {
b.lock.Lock()
defer b.lock.Unlock()
if result == nil && panicValue == nil {
if b.state == halfOpen {
b.successes++
if b.successes == b.successThreshold {
b.closeBreaker()
}
}
} else {
if b.errors > 0 {
expiry := b.lastError.Add(b.timeout)
if time.Now().After(expiry) {
b.errors = 0
}
}
switch b.state {
case closed:
b.errors++
if b.errors == b.errorThreshold {
b.openBreaker()
} else {
b.lastError = time.Now()
}
case halfOpen:
b.openBreaker()
}
}
}
func (b *Breaker) openBreaker() {
b.changeState(open)
go b.timer()
}
func (b *Breaker) closeBreaker() {
b.changeState(closed)
}
func (b *Breaker) timer() {
time.Sleep(b.timeout)
b.lock.Lock()
defer b.lock.Unlock()
b.changeState(halfOpen)
}
func (b *Breaker) changeState(newState uint32) {
b.errors = 0
b.successes = 0
atomic.StoreUint32(&b.state, newState)
}
vendor/github.com/eapache/go-xerial-snappy/LICENSE
Generated Vendored
+21
View File
@@ -0,0 +1,21 @@
The MIT License (MIT)
Copyright (c) 2016 Evan Huus
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
vendor/github.com/eapache/go-xerial-snappy/README.md
Generated Vendored
+13
View File
@@ -0,0 +1,13 @@
# go-xerial-snappy
[![Build Status](https://travis-ci.org/eapache/go-xerial-snappy.svg?branch=master)](https://travis-ci.org/eapache/go-xerial-snappy)
Xerial-compatible Snappy framing support for golang.
Packages using Xerial for snappy encoding use a framing format incompatible with
basically everything else in existence. This package wraps Go's built-in snappy
package to support it.
Apps that use this format include Apache Kafka (see
https://github.com/dpkp/kafka-python/issues/126#issuecomment-35478921 for
details).
vendor/github.com/eapache/go-xerial-snappy/snappy.go
Generated Vendored
+43
View File
@@ -0,0 +1,43 @@
package snappy
import (
"bytes"
"encoding/binary"
master "github.com/golang/snappy"
)
var xerialHeader = []byte{130, 83, 78, 65, 80, 80, 89, 0}
// Encode encodes data as snappy with no framing header.
func Encode(src []byte) []byte {
return master.Encode(nil, src)
}
// Decode decodes snappy data whether it is traditional unframed
// or includes the xerial framing format.
func Decode(src []byte) ([]byte, error) {
if !bytes.Equal(src[:8], xerialHeader) {
return master.Decode(nil, src)
}
var (
pos = uint32(16)
max = uint32(len(src))
dst = make([]byte, 0, len(src))
chunk []byte
err error
)
for pos < max {
size := binary.BigEndian.Uint32(src[pos : pos+4])
pos += 4
chunk, err = master.Decode(chunk, src[pos:pos+size])
if err != nil {
return nil, err
}
pos += size
dst = append(dst, chunk...)
}
return dst, nil
}
vendor/github.com/eapache/queue/LICENSE
Generated Vendored
+21
View File
@@ -0,0 +1,21 @@
The MIT License (MIT)
Copyright (c) 2014 Evan Huus
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
vendor/github.com/eapache/queue/README.md
Generated Vendored
+16
View File
@@ -0,0 +1,16 @@
Queue
=====
[![Build Status](https://travis-ci.org/eapache/queue.svg)](https://travis-ci.org/eapache/queue)
[![GoDoc](https://godoc.org/github.com/eapache/queue?status.png)](https://godoc.org/github.com/eapache/queue)
[![Code of Conduct](https://img.shields.io/badge/code%20of%20conduct-active-blue.svg)](https://eapache.github.io/conduct.html)
A fast Golang queue using a ring-buffer, based on the version suggested by Dariusz Górecki.
Using this instead of other, simpler, queue implementations (slice+append or linked list) provides
substantial memory and time benefits, and fewer GC pauses.
The queue implemented here is as fast as it is in part because it is *not* thread-safe.
Follows semantic versioning using https://gopkg.in/ - import from
[`gopkg.in/eapache/queue.v1`](https://gopkg.in/eapache/queue.v1)
for guaranteed API stability.
vendor/github.com/eapache/queue/queue.go
Generated Vendored
+102
View File
@@ -0,0 +1,102 @@
/*
Package queue provides a fast, ring-buffer queue based on the version suggested by Dariusz Górecki.
Using this instead of other, simpler, queue implementations (slice+append or linked list) provides
substantial memory and time benefits, and fewer GC pauses.
The queue implemented here is as fast as it is for an additional reason: it is *not* thread-safe.
*/
package queue
// minQueueLen is smallest capacity that queue may have.
// Must be power of 2 for bitwise modulus: x % n == x & (n - 1).
const minQueueLen = 16
// Queue represents a single instance of the queue data structure.
type Queue struct {
buf []interface{}
head, tail, count int
}
// New constructs and returns a new Queue.
func New() *Queue {
return &Queue{
buf: make([]interface{}, minQueueLen),
}
}
// Length returns the number of elements currently stored in the queue.
func (q *Queue) Length() int {
return q.count
}
// resizes the queue to fit exactly twice its current contents
// this can result in shrinking if the queue is less than half-full
func (q *Queue) resize() {
newBuf := make([]interface{}, q.count<<1)
if q.tail > q.head {
copy(newBuf, q.buf[q.head:q.tail])
} else {
n := copy(newBuf, q.buf[q.head:])
copy(newBuf[n:], q.buf[:q.tail])
}
q.head = 0
q.tail = q.count
q.buf = newBuf
}
// Add puts an element on the end of the queue.
func (q *Queue) Add(elem interface{}) {
if q.count == len(q.buf) {
q.resize()
}
q.buf[q.tail] = elem
// bitwise modulus
q.tail = (q.tail + 1) & (len(q.buf) - 1)
q.count++
}
// Peek returns the element at the head of the queue. This call panics
// if the queue is empty.
func (q *Queue) Peek() interface{} {
if q.count <= 0 {
panic("queue: Peek() called on empty queue")
}
return q.buf[q.head]
}
// Get returns the element at index i in the queue. If the index is
// invalid, the call will panic. This method accepts both positive and
// negative index values. Index 0 refers to the first element, and
// index -1 refers to the last.
func (q *Queue) Get(i int) interface{} {
// If indexing backwards, convert to positive index.
if i < 0 {
i += q.count
}
if i < 0 || i >= q.count {
panic("queue: Get() called with index out of range")
}
// bitwise modulus
return q.buf[(q.head+i)&(len(q.buf)-1)]
}
// Remove removes and returns the element from the front of the queue. If the
// queue is empty, the call will panic.
func (q *Queue) Remove() interface{} {
if q.count <= 0 {
panic("queue: Remove() called on empty queue")
}
ret := q.buf[q.head]
q.buf[q.head] = nil
// bitwise modulus
q.head = (q.head + 1) & (len(q.buf) - 1)
q.count--
// Resize down if buffer 1/4 full.
if len(q.buf) > minQueueLen && (q.count<<2) == len(q.buf) {
q.resize()
}
return ret
}
vendor/github.com/golang/snappy/AUTHORS
Generated Vendored
+15
View File
@@ -0,0 +1,15 @@
# This is the official list of Snappy-Go authors for copyright purposes.
# This file is distinct from the CONTRIBUTORS files.
# See the latter for an explanation.
# Names should be added to this file as
# Name or Organization <email address>
# The email address is not required for organizations.
# Please keep the list sorted.
Damian Gryski <dgryski@gmail.com>
Google Inc.
Jan Mercl <0xjnml@gmail.com>
Rodolfo Carvalho <rhcarvalho@gmail.com>
Sebastien Binet <seb.binet@gmail.com>
vendor/github.com/golang/snappy/CONTRIBUTORS
Generated Vendored
+37
View File
@@ -0,0 +1,37 @@
# This is the official list of people who can contribute
# (and typically have contributed) code to the Snappy-Go repository.
# The AUTHORS file lists the copyright holders; this file
# lists people. For example, Google employees are listed here
# but not in AUTHORS, because Google holds the copyright.
#
# The submission process automatically checks to make sure
# that people submitting code are listed in this file (by email address).
#
# Names should be added to this file only after verifying that
# the individual or the individual's organization has agreed to
# the appropriate Contributor License Agreement, found here:
#
# http://code.google.com/legal/individual-cla-v1.0.html
# http://code.google.com/legal/corporate-cla-v1.0.html
#
# The agreement for individuals can be filled out on the web.
#
# When adding J Random Contributor's name to this file,
# either J's name or J's organization's name should be
# added to the AUTHORS file, depending on whether the
# individual or corporate CLA was used.
# Names should be added to this file like so:
# Name <email address>
# Please keep the list sorted.
Damian Gryski <dgryski@gmail.com>
Jan Mercl <0xjnml@gmail.com>
Kai Backman <kaib@golang.org>
Marc-Antoine Ruel <maruel@chromium.org>
Nigel Tao <nigeltao@golang.org>
Rob Pike <r@golang.org>
Rodolfo Carvalho <rhcarvalho@gmail.com>
Russ Cox <rsc@golang.org>
Sebastien Binet <seb.binet@gmail.com>
vendor/github.com/golang/snappy/LICENSE
Generated Vendored
+27
View File
@@ -0,0 +1,27 @@
Copyright (c) 2011 The Snappy-Go Authors. All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.
* Neither the name of Google Inc. nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
vendor/github.com/golang/snappy/README
Generated Vendored
+107
View File
@@ -0,0 +1,107 @@
The Snappy compression format in the Go programming language.
To download and install from source:
$ go get github.com/golang/snappy
Unless otherwise noted, the Snappy-Go source files are distributed
under the BSD-style license found in the LICENSE file.
Benchmarks.
The golang/snappy benchmarks include compressing (Z) and decompressing (U) ten
or so files, the same set used by the C++ Snappy code (github.com/google/snappy
and note the "google", not "golang"). On an "Intel(R) Core(TM) i7-3770 CPU @
3.40GHz", Go's GOARCH=amd64 numbers as of 2016-05-29:
"go test -test.bench=."
_UFlat0-8 2.19GB/s ± 0% html
_UFlat1-8 1.41GB/s ± 0% urls
_UFlat2-8 23.5GB/s ± 2% jpg
_UFlat3-8 1.91GB/s ± 0% jpg_200
_UFlat4-8 14.0GB/s ± 1% pdf
_UFlat5-8 1.97GB/s ± 0% html4
_UFlat6-8 814MB/s ± 0% txt1
_UFlat7-8 785MB/s ± 0% txt2
_UFlat8-8 857MB/s ± 0% txt3
_UFlat9-8 719MB/s ± 1% txt4
_UFlat10-8 2.84GB/s ± 0% pb
_UFlat11-8 1.05GB/s ± 0% gaviota
_ZFlat0-8 1.04GB/s ± 0% html
_ZFlat1-8 534MB/s ± 0% urls
_ZFlat2-8 15.7GB/s ± 1% jpg
_ZFlat3-8 740MB/s ± 3% jpg_200
_ZFlat4-8 9.20GB/s ± 1% pdf
_ZFlat5-8 991MB/s ± 0% html4
_ZFlat6-8 379MB/s ± 0% txt1
_ZFlat7-8 352MB/s ± 0% txt2
_ZFlat8-8 396MB/s ± 1% txt3
_ZFlat9-8 327MB/s ± 1% txt4
_ZFlat10-8 1.33GB/s ± 1% pb
_ZFlat11-8 605MB/s ± 1% gaviota
"go test -test.bench=. -tags=noasm"
_UFlat0-8 621MB/s ± 2% html
_UFlat1-8 494MB/s ± 1% urls
_UFlat2-8 23.2GB/s ± 1% jpg
_UFlat3-8 1.12GB/s ± 1% jpg_200
_UFlat4-8 4.35GB/s ± 1% pdf
_UFlat5-8 609MB/s ± 0% html4
_UFlat6-8 296MB/s ± 0% txt1
_UFlat7-8 288MB/s ± 0% txt2
_UFlat8-8 309MB/s ± 1% txt3
_UFlat9-8 280MB/s ± 1% txt4
_UFlat10-8 753MB/s ± 0% pb
_UFlat11-8 400MB/s ± 0% gaviota
_ZFlat0-8 409MB/s ± 1% html
_ZFlat1-8 250MB/s ± 1% urls
_ZFlat2-8 12.3GB/s ± 1% jpg
_ZFlat3-8 132MB/s ± 0% jpg_200
_ZFlat4-8 2.92GB/s ± 0% pdf
_ZFlat5-8 405MB/s ± 1% html4
_ZFlat6-8 179MB/s ± 1% txt1
_ZFlat7-8 170MB/s ± 1% txt2
_ZFlat8-8 189MB/s ± 1% txt3
_ZFlat9-8 164MB/s ± 1% txt4
_ZFlat10-8 479MB/s ± 1% pb
_ZFlat11-8 270MB/s ± 1% gaviota
For comparison (Go's encoded output is byte-for-byte identical to C++'s), here
are the numbers from C++ Snappy's
make CXXFLAGS="-O2 -DNDEBUG -g" clean snappy_unittest.log && cat snappy_unittest.log
BM_UFlat/0 2.4GB/s html
BM_UFlat/1 1.4GB/s urls
BM_UFlat/2 21.8GB/s jpg
BM_UFlat/3 1.5GB/s jpg_200
BM_UFlat/4 13.3GB/s pdf
BM_UFlat/5 2.1GB/s html4
BM_UFlat/6 1.0GB/s txt1
BM_UFlat/7 959.4MB/s txt2
BM_UFlat/8 1.0GB/s txt3
BM_UFlat/9 864.5MB/s txt4
BM_UFlat/10 2.9GB/s pb
BM_UFlat/11 1.2GB/s gaviota
BM_ZFlat/0 944.3MB/s html (22.31 %)
BM_ZFlat/1 501.6MB/s urls (47.78 %)
BM_ZFlat/2 14.3GB/s jpg (99.95 %)
BM_ZFlat/3 538.3MB/s jpg_200 (73.00 %)
BM_ZFlat/4 8.3GB/s pdf (83.30 %)
BM_ZFlat/5 903.5MB/s html4 (22.52 %)
BM_ZFlat/6 336.0MB/s txt1 (57.88 %)
BM_ZFlat/7 312.3MB/s txt2 (61.91 %)
BM_ZFlat/8 353.1MB/s txt3 (54.99 %)
BM_ZFlat/9 289.9MB/s txt4 (66.26 %)
BM_ZFlat/10 1.2GB/s pb (19.68 %)
BM_ZFlat/11 527.4MB/s gaviota (37.72 %)
vendor/github.com/golang/snappy/decode.go
Generated Vendored
+237
View File
@@ -0,0 +1,237 @@
// Copyright 2011 The Snappy-Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package snappy
import (
"encoding/binary"
"errors"
"io"
)
var (
// ErrCorrupt reports that the input is invalid.
ErrCorrupt = errors.New("snappy: corrupt input")
// ErrTooLarge reports that the uncompressed length is too large.
ErrTooLarge = errors.New("snappy: decoded block is too large")
// ErrUnsupported reports that the input isn't supported.
ErrUnsupported = errors.New("snappy: unsupported input")
errUnsupportedLiteralLength = errors.New("snappy: unsupported literal length")
)
// DecodedLen returns the length of the decoded block.
func DecodedLen(src []byte) (int, error) {
v, _, err := decodedLen(src)
return v, err
}
// decodedLen returns the length of the decoded block and the number of bytes
// that the length header occupied.
func decodedLen(src []byte) (blockLen, headerLen int, err error) {
v, n := binary.Uvarint(src)
if n <= 0 || v > 0xffffffff {
return 0, 0, ErrCorrupt
}
const wordSize = 32 << (^uint(0) >> 32 & 1)
if wordSize == 32 && v > 0x7fffffff {
return 0, 0, ErrTooLarge
}
return int(v), n, nil
}
const (
decodeErrCodeCorrupt = 1
decodeErrCodeUnsupportedLiteralLength = 2
)
// Decode returns the decoded form of src. The returned slice may be a sub-
// slice of dst if dst was large enough to hold the entire decoded block.
// Otherwise, a newly allocated slice will be returned.
//
// The dst and src must not overlap. It is valid to pass a nil dst.
func Decode(dst, src []byte) ([]byte, error) {
dLen, s, err := decodedLen(src)
if err != nil {
return nil, err
}
if dLen <= len(dst) {
dst = dst[:dLen]
} else {
dst = make([]byte, dLen)
}
switch decode(dst, src[s:]) {
case 0:
return dst, nil
case decodeErrCodeUnsupportedLiteralLength:
return nil, errUnsupportedLiteralLength
}
return nil, ErrCorrupt
}
// NewReader returns a new Reader that decompresses from r, using the framing
// format described at
// https://github.com/google/snappy/blob/master/framing_format.txt
func NewReader(r io.Reader) *Reader {
return &Reader{
r: r,
decoded: make([]byte, maxBlockSize),
buf: make([]byte, maxEncodedLenOfMaxBlockSize+checksumSize),
}
}
// Reader is an io.Reader that can read Snappy-compressed bytes.
type Reader struct {
r io.Reader
err error
decoded []byte
buf []byte
// decoded[i:j] contains decoded bytes that have not yet been passed on.
i, j int
readHeader bool
}
// Reset discards any buffered data, resets all state, and switches the Snappy
// reader to read from r. This permits reusing a Reader rather than allocating
// a new one.
func (r *Reader) Reset(reader io.Reader) {
r.r = reader
r.err = nil
r.i = 0
r.j = 0
r.readHeader = false
}
func (r *Reader) readFull(p []byte, allowEOF bool) (ok bool) {
if _, r.err = io.ReadFull(r.r, p); r.err != nil {
if r.err == io.ErrUnexpectedEOF || (r.err == io.EOF && !allowEOF) {
r.err = ErrCorrupt
}
return false
}
return true
}
// Read satisfies the io.Reader interface.
func (r *Reader) Read(p []byte) (int, error) {
if r.err != nil {
return 0, r.err
}
for {
if r.i < r.j {
n := copy(p, r.decoded[r.i:r.j])
r.i += n
return n, nil
}
if !r.readFull(r.buf[:4], true) {
return 0, r.err
}
chunkType := r.buf[0]
if !r.readHeader {
if chunkType != chunkTypeStreamIdentifier {
r.err = ErrCorrupt
return 0, r.err
}
r.readHeader = true
}
chunkLen := int(r.buf[1]) | int(r.buf[2])<<8 | int(r.buf[3])<<16
if chunkLen > len(r.buf) {
r.err = ErrUnsupported
return 0, r.err
}
// The chunk types are specified at
// https://github.com/google/snappy/blob/master/framing_format.txt
switch chunkType {
case chunkTypeCompressedData:
// Section 4.2. Compressed data (chunk type 0x00).
if chunkLen < checksumSize {
r.err = ErrCorrupt
return 0, r.err
}
buf := r.buf[:chunkLen]
if !r.readFull(buf, false) {
return 0, r.err
}
checksum := uint32(buf[0]) | uint32(buf[1])<<8 | uint32(buf[2])<<16 | uint32(buf[3])<<24
buf = buf[checksumSize:]
n, err := DecodedLen(buf)
if err != nil {
r.err = err
return 0, r.err
}
if n > len(r.decoded) {
r.err = ErrCorrupt
return 0, r.err
}
if _, err := Decode(r.decoded, buf); err != nil {
r.err = err
return 0, r.err
}
if crc(r.decoded[:n]) != checksum {
r.err = ErrCorrupt
return 0, r.err
}
r.i, r.j = 0, n
continue
case chunkTypeUncompressedData:
// Section 4.3. Uncompressed data (chunk type 0x01).
if chunkLen < checksumSize {
r.err = ErrCorrupt
return 0, r.err
}
buf := r.buf[:checksumSize]
if !r.readFull(buf, false) {
return 0, r.err
}
checksum := uint32(buf[0]) | uint32(buf[1])<<8 | uint32(buf[2])<<16 | uint32(buf[3])<<24
// Read directly into r.decoded instead of via r.buf.
n := chunkLen - checksumSize
if n > len(r.decoded) {
r.err = ErrCorrupt
return 0, r.err
}
if !r.readFull(r.decoded[:n], false) {
return 0, r.err
}
if crc(r.decoded[:n]) != checksum {
r.err = ErrCorrupt
return 0, r.err
}
r.i, r.j = 0, n
continue
case chunkTypeStreamIdentifier:
// Section 4.1. Stream identifier (chunk type 0xff).
if chunkLen != len(magicBody) {
r.err = ErrCorrupt
return 0, r.err
}
if !r.readFull(r.buf[:len(magicBody)], false) {
return 0, r.err
}
for i := 0; i < len(magicBody); i++ {
if r.buf[i] != magicBody[i] {
r.err = ErrCorrupt
return 0, r.err
}
}
continue
}
if chunkType <= 0x7f {
// Section 4.5. Reserved unskippable chunks (chunk types 0x02-0x7f).
r.err = ErrUnsupported
return 0, r.err
}
// Section 4.4 Padding (chunk type 0xfe).
// Section 4.6. Reserved skippable chunks (chunk types 0x80-0xfd).
if !r.readFull(r.buf[:chunkLen], false) {
return 0, r.err
}
}
}
vendor/github.com/golang/snappy/decode_amd64.go
Generated Vendored
+14
View File
@@ -0,0 +1,14 @@
// Copyright 2016 The Snappy-Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !appengine
// +build gc
// +build !noasm
package snappy
// decode has the same semantics as in decode_other.go.
//
//go:noescape
func decode(dst, src []byte) int
vendor/github.com/golang/snappy/decode_amd64.s
Generated Vendored
+490
View File
@@ -0,0 +1,490 @@
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !appengine
// +build gc
// +build !noasm
#include "textflag.h"
// The asm code generally follows the pure Go code in decode_other.go, except
// where marked with a "!!!".
// func decode(dst, src []byte) int
//
// All local variables fit into registers. The non-zero stack size is only to
// spill registers and push args when issuing a CALL. The register allocation:
// - AX scratch
// - BX scratch
// - CX length or x
// - DX offset
// - SI &src[s]
// - DI &dst[d]
// + R8 dst_base
// + R9 dst_len
// + R10 dst_base + dst_len
// + R11 src_base
// + R12 src_len
// + R13 src_base + src_len
// - R14 used by doCopy
// - R15 used by doCopy
//
// The registers R8-R13 (marked with a "+") are set at the start of the
// function, and after a CALL returns, and are not otherwise modified.
//
// The d variable is implicitly DI - R8, and len(dst)-d is R10 - DI.
// The s variable is implicitly SI - R11, and len(src)-s is R13 - SI.
TEXT ·decode(SB), NOSPLIT, $48-56
// Initialize SI, DI and R8-R13.
MOVQ dst_base+0(FP), R8
MOVQ dst_len+8(FP), R9
MOVQ R8, DI
MOVQ R8, R10
ADDQ R9, R10
MOVQ src_base+24(FP), R11
MOVQ src_len+32(FP), R12
MOVQ R11, SI
MOVQ R11, R13
ADDQ R12, R13
loop:
// for s < len(src)
CMPQ SI, R13
JEQ end
// CX = uint32(src[s])
//
// switch src[s] & 0x03
MOVBLZX (SI), CX
MOVL CX, BX
ANDL $3, BX
CMPL BX, $1
JAE tagCopy
// ----------------------------------------
// The code below handles literal tags.
// case tagLiteral:
// x := uint32(src[s] >> 2)
// switch
SHRL $2, CX
CMPL CX, $60
JAE tagLit60Plus
// case x < 60:
// s++
INCQ SI
doLit:
// This is the end of the inner "switch", when we have a literal tag.
//
// We assume that CX == x and x fits in a uint32, where x is the variable
// used in the pure Go decode_other.go code.
// length = int(x) + 1
//
// Unlike the pure Go code, we don't need to check if length <= 0 because
// CX can hold 64 bits, so the increment cannot overflow.
INCQ CX
// Prepare to check if copying length bytes will run past the end of dst or
// src.
//
// AX = len(dst) - d
// BX = len(src) - s
MOVQ R10, AX
SUBQ DI, AX
MOVQ R13, BX
SUBQ SI, BX
// !!! Try a faster technique for short (16 or fewer bytes) copies.
//
// if length > 16 || len(dst)-d < 16 || len(src)-s < 16 {
// goto callMemmove // Fall back on calling runtime·memmove.
// }
//
// The C++ snappy code calls this TryFastAppend. It also checks len(src)-s
// against 21 instead of 16, because it cannot assume that all of its input
// is contiguous in memory and so it needs to leave enough source bytes to
// read the next tag without refilling buffers, but Go's Decode assumes
// contiguousness (the src argument is a []byte).
CMPQ CX, $16
JGT callMemmove
CMPQ AX, $16
JLT callMemmove
CMPQ BX, $16
JLT callMemmove
// !!! Implement the copy from src to dst as a 16-byte load and store.
// (Decode's documentation says that dst and src must not overlap.)
//
// This always copies 16 bytes, instead of only length bytes, but that's
// OK. If the input is a valid Snappy encoding then subsequent iterations
// will fix up the overrun. Otherwise, Decode returns a nil []byte (and a
// non-nil error), so the overrun will be ignored.
//
// Note that on amd64, it is legal and cheap to issue unaligned 8-byte or
// 16-byte loads and stores. This technique probably wouldn't be as
// effective on architectures that are fussier about alignment.
MOVOU 0(SI), X0
MOVOU X0, 0(DI)
// d += length
// s += length
ADDQ CX, DI
ADDQ CX, SI
JMP loop
callMemmove:
// if length > len(dst)-d || length > len(src)-s { etc }
CMPQ CX, AX
JGT errCorrupt
CMPQ CX, BX
JGT errCorrupt
// copy(dst[d:], src[s:s+length])
//
// This means calling runtime·memmove(&dst[d], &src[s], length), so we push
// DI, SI and CX as arguments. Coincidentally, we also need to spill those
// three registers to the stack, to save local variables across the CALL.
MOVQ DI, 0(SP)
MOVQ SI, 8(SP)
MOVQ CX, 16(SP)
MOVQ DI, 24(SP)
MOVQ SI, 32(SP)
MOVQ CX, 40(SP)
CALL runtime·memmove(SB)
// Restore local variables: unspill registers from the stack and
// re-calculate R8-R13.
MOVQ 24(SP), DI
MOVQ 32(SP), SI
MOVQ 40(SP), CX
MOVQ dst_base+0(FP), R8
MOVQ dst_len+8(FP), R9
MOVQ R8, R10
ADDQ R9, R10
MOVQ src_base+24(FP), R11
MOVQ src_len+32(FP), R12
MOVQ R11, R13
ADDQ R12, R13
// d += length
// s += length
ADDQ CX, DI
ADDQ CX, SI
JMP loop
tagLit60Plus:
// !!! This fragment does the
//
// s += x - 58; if uint(s) > uint(len(src)) { etc }
//
// checks. In the asm version, we code it once instead of once per switch case.
ADDQ CX, SI
SUBQ $58, SI
MOVQ SI, BX
SUBQ R11, BX
CMPQ BX, R12
JA errCorrupt
// case x == 60:
CMPL CX, $61
JEQ tagLit61
JA tagLit62Plus
// x = uint32(src[s-1])
MOVBLZX -1(SI), CX
JMP doLit
tagLit61:
// case x == 61:
// x = uint32(src[s-2]) | uint32(src[s-1])<<8
MOVWLZX -2(SI), CX
JMP doLit
tagLit62Plus:
CMPL CX, $62
JA tagLit63
// case x == 62:
// x = uint32(src[s-3]) | uint32(src[s-2])<<8 | uint32(src[s-1])<<16
MOVWLZX -3(SI), CX
MOVBLZX -1(SI), BX
SHLL $16, BX
ORL BX, CX
JMP doLit
tagLit63:
// case x == 63:
// x = uint32(src[s-4]) | uint32(src[s-3])<<8 | uint32(src[s-2])<<16 | uint32(src[s-1])<<24
MOVL -4(SI), CX
JMP doLit
// The code above handles literal tags.
// ----------------------------------------
// The code below handles copy tags.
tagCopy4:
// case tagCopy4:
// s += 5
ADDQ $5, SI
// if uint(s) > uint(len(src)) { etc }
MOVQ SI, BX
SUBQ R11, BX
CMPQ BX, R12
JA errCorrupt
// length = 1 + int(src[s-5])>>2
SHRQ $2, CX
INCQ CX
// offset = int(uint32(src[s-4]) | uint32(src[s-3])<<8 | uint32(src[s-2])<<16 | uint32(src[s-1])<<24)
MOVLQZX -4(SI), DX
JMP doCopy
tagCopy2:
// case tagCopy2:
// s += 3
ADDQ $3, SI
// if uint(s) > uint(len(src)) { etc }
MOVQ SI, BX
SUBQ R11, BX
CMPQ BX, R12
JA errCorrupt
// length = 1 + int(src[s-3])>>2
SHRQ $2, CX
INCQ CX
// offset = int(uint32(src[s-2]) | uint32(src[s-1])<<8)
MOVWQZX -2(SI), DX
JMP doCopy
tagCopy:
// We have a copy tag. We assume that:
// - BX == src[s] & 0x03
// - CX == src[s]
CMPQ BX, $2
JEQ tagCopy2
JA tagCopy4
// case tagCopy1:
// s += 2
ADDQ $2, SI
// if uint(s) > uint(len(src)) { etc }
MOVQ SI, BX
SUBQ R11, BX
CMPQ BX, R12
JA errCorrupt
// offset = int(uint32(src[s-2])&0xe0<<3 | uint32(src[s-1]))
MOVQ CX, DX
ANDQ $0xe0, DX
SHLQ $3, DX
MOVBQZX -1(SI), BX
ORQ BX, DX
// length = 4 + int(src[s-2])>>2&0x7
SHRQ $2, CX
ANDQ $7, CX
ADDQ $4, CX
doCopy:
// This is the end of the outer "switch", when we have a copy tag.
//
// We assume that:
// - CX == length && CX > 0
// - DX == offset
// if offset <= 0 { etc }
CMPQ DX, $0
JLE errCorrupt
// if d < offset { etc }
MOVQ DI, BX
SUBQ R8, BX
CMPQ BX, DX
JLT errCorrupt
// if length > len(dst)-d { etc }
MOVQ R10, BX
SUBQ DI, BX
CMPQ CX, BX
JGT errCorrupt
// forwardCopy(dst[d:d+length], dst[d-offset:]); d += length
//
// Set:
// - R14 = len(dst)-d
// - R15 = &dst[d-offset]
MOVQ R10, R14
SUBQ DI, R14
MOVQ DI, R15
SUBQ DX, R15
// !!! Try a faster technique for short (16 or fewer bytes) forward copies.
//
// First, try using two 8-byte load/stores, similar to the doLit technique
// above. Even if dst[d:d+length] and dst[d-offset:] can overlap, this is
// still OK if offset >= 8. Note that this has to be two 8-byte load/stores
// and not one 16-byte load/store, and the first store has to be before the
// second load, due to the overlap if offset is in the range [8, 16).
//
// if length > 16 || offset < 8 || len(dst)-d < 16 {
// goto slowForwardCopy
// }
// copy 16 bytes
// d += length
CMPQ CX, $16
JGT slowForwardCopy
CMPQ DX, $8
JLT slowForwardCopy
CMPQ R14, $16
JLT slowForwardCopy
MOVQ 0(R15), AX
MOVQ AX, 0(DI)
MOVQ 8(R15), BX
MOVQ BX, 8(DI)
ADDQ CX, DI
JMP loop
slowForwardCopy:
// !!! If the forward copy is longer than 16 bytes, or if offset < 8, we
// can still try 8-byte load stores, provided we can overrun up to 10 extra
// bytes. As above, the overrun will be fixed up by subsequent iterations
// of the outermost loop.
//
// The C++ snappy code calls this technique IncrementalCopyFastPath. Its
// commentary says:
//
// ----
//
// The main part of this loop is a simple copy of eight bytes at a time
// until we've copied (at least) the requested amount of bytes. However,
// if d and d-offset are less than eight bytes apart (indicating a
// repeating pattern of length < 8), we first need to expand the pattern in
// order to get the correct results. For instance, if the buffer looks like
// this, with the eight-byte <d-offset> and <d> patterns marked as
// intervals:
//
// abxxxxxxxxxxxx
// [------] d-offset
// [------] d
//
// a single eight-byte copy from <d-offset> to <d> will repeat the pattern
// once, after which we can move <d> two bytes without moving <d-offset>:
//
// ababxxxxxxxxxx
// [------] d-offset
// [------] d
//
// and repeat the exercise until the two no longer overlap.
//
// This allows us to do very well in the special case of one single byte
// repeated many times, without taking a big hit for more general cases.
//
// The worst case of extra writing past the end of the match occurs when
// offset == 1 and length == 1; the last copy will read from byte positions
// [0..7] and write to [4..11], whereas it was only supposed to write to
// position 1. Thus, ten excess bytes.
//
// ----
//
// That "10 byte overrun" worst case is confirmed by Go's
// TestSlowForwardCopyOverrun, which also tests the fixUpSlowForwardCopy
// and finishSlowForwardCopy algorithm.
//
// if length > len(dst)-d-10 {
// goto verySlowForwardCopy
// }
SUBQ $10, R14
CMPQ CX, R14
JGT verySlowForwardCopy
makeOffsetAtLeast8:
// !!! As above, expand the pattern so that offset >= 8 and we can use
// 8-byte load/stores.
//
// for offset < 8 {
// copy 8 bytes from dst[d-offset:] to dst[d:]
// length -= offset
// d += offset
// offset += offset
// // The two previous lines together means that d-offset, and therefore
// // R15, is unchanged.
// }
CMPQ DX, $8
JGE fixUpSlowForwardCopy
MOVQ (R15), BX
MOVQ BX, (DI)
SUBQ DX, CX
ADDQ DX, DI
ADDQ DX, DX
JMP makeOffsetAtLeast8
fixUpSlowForwardCopy:
// !!! Add length (which might be negative now) to d (implied by DI being
// &dst[d]) so that d ends up at the right place when we jump back to the
// top of the loop. Before we do that, though, we save DI to AX so that, if
// length is positive, copying the remaining length bytes will write to the
// right place.
MOVQ DI, AX
ADDQ CX, DI
finishSlowForwardCopy:
// !!! Repeat 8-byte load/stores until length <= 0. Ending with a negative
// length means that we overrun, but as above, that will be fixed up by
// subsequent iterations of the outermost loop.
CMPQ CX, $0
JLE loop
MOVQ (R15), BX
MOVQ BX, (AX)
ADDQ $8, R15
ADDQ $8, AX
SUBQ $8, CX
JMP finishSlowForwardCopy
verySlowForwardCopy:
// verySlowForwardCopy is a simple implementation of forward copy. In C
// parlance, this is a do/while loop instead of a while loop, since we know
// that length > 0. In Go syntax:
//
// for {
// dst[d] = dst[d - offset]
// d++
// length--
// if length == 0 {
// break
// }
// }
MOVB (R15), BX
MOVB BX, (DI)
INCQ R15
INCQ DI
DECQ CX
JNZ verySlowForwardCopy
JMP loop
// The code above handles copy tags.
// ----------------------------------------
end:
// This is the end of the "for s < len(src)".
//
// if d != len(dst) { etc }
CMPQ DI, R10
JNE errCorrupt
// return 0
MOVQ $0, ret+48(FP)
RET
errCorrupt:
// return decodeErrCodeCorrupt
MOVQ $1, ret+48(FP)
RET
vendor/github.com/golang/snappy/encode.go
Generated Vendored
+285
View File
@@ -0,0 +1,285 @@
// Copyright 2011 The Snappy-Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package snappy
import (
"encoding/binary"
"errors"
"io"
)
// Encode returns the encoded form of src. The returned slice may be a sub-
// slice of dst if dst was large enough to hold the entire encoded block.
// Otherwise, a newly allocated slice will be returned.
//
// The dst and src must not overlap. It is valid to pass a nil dst.
func Encode(dst, src []byte) []byte {
if n := MaxEncodedLen(len(src)); n < 0 {
panic(ErrTooLarge)
} else if len(dst) < n {
dst = make([]byte, n)
}
// The block starts with the varint-encoded length of the decompressed bytes.
d := binary.PutUvarint(dst, uint64(len(src)))
for len(src) > 0 {
p := src
src = nil
if len(p) > maxBlockSize {
p, src = p[:maxBlockSize], p[maxBlockSize:]
}
if len(p) < minNonLiteralBlockSize {
d += emitLiteral(dst[d:], p)
} else {
d += encodeBlock(dst[d:], p)
}
}
return dst[:d]
}
// inputMargin is the minimum number of extra input bytes to keep, inside
// encodeBlock's inner loop. On some architectures, this margin lets us
// implement a fast path for emitLiteral, where the copy of short (<= 16 byte)
// literals can be implemented as a single load to and store from a 16-byte
// register. That literal's actual length can be as short as 1 byte, so this
// can copy up to 15 bytes too much, but that's OK as subsequent iterations of
// the encoding loop will fix up the copy overrun, and this inputMargin ensures
// that we don't overrun the dst and src buffers.
const inputMargin = 16 - 1
// minNonLiteralBlockSize is the minimum size of the input to encodeBlock that
// could be encoded with a copy tag. This is the minimum with respect to the
// algorithm used by encodeBlock, not a minimum enforced by the file format.
//
// The encoded output must start with at least a 1 byte literal, as there are
// no previous bytes to copy. A minimal (1 byte) copy after that, generated
// from an emitCopy call in encodeBlock's main loop, would require at least
// another inputMargin bytes, for the reason above: we want any emitLiteral
// calls inside encodeBlock's main loop to use the fast path if possible, which
// requires being able to overrun by inputMargin bytes. Thus,
// minNonLiteralBlockSize equals 1 + 1 + inputMargin.
//
// The C++ code doesn't use this exact threshold, but it could, as discussed at
// https://groups.google.com/d/topic/snappy-compression/oGbhsdIJSJ8/discussion
// The difference between Go (2+inputMargin) and C++ (inputMargin) is purely an
// optimization. It should not affect the encoded form. This is tested by
// TestSameEncodingAsCppShortCopies.
const minNonLiteralBlockSize = 1 + 1 + inputMargin
// MaxEncodedLen returns the maximum length of a snappy block, given its
// uncompressed length.
//
// It will return a negative value if srcLen is too large to encode.
func MaxEncodedLen(srcLen int) int {
n := uint64(srcLen)
if n > 0xffffffff {
return -1
}
// Compressed data can be defined as:
// compressed := item* literal*
// item := literal* copy
//
// The trailing literal sequence has a space blowup of at most 62/60
// since a literal of length 60 needs one tag byte + one extra byte
// for length information.
//
// Item blowup is trickier to measure. Suppose the "copy" op copies
// 4 bytes of data. Because of a special check in the encoding code,
// we produce a 4-byte copy only if the offset is < 65536. Therefore
// the copy op takes 3 bytes to encode, and this type of item leads
// to at most the 62/60 blowup for representing literals.
//
// Suppose the "copy" op copies 5 bytes of data. If the offset is big
// enough, it will take 5 bytes to encode the copy op. Therefore the
// worst case here is a one-byte literal followed by a five-byte copy.
// That is, 6 bytes of input turn into 7 bytes of "compressed" data.
//
// This last factor dominates the blowup, so the final estimate is:
n = 32 + n + n/6
if n > 0xffffffff {
return -1
}
return int(n)
}
var errClosed = errors.New("snappy: Writer is closed")
// NewWriter returns a new Writer that compresses to w.
//
// The Writer returned does not buffer writes. There is no need to Flush or
// Close such a Writer.
//
// Deprecated: the Writer returned is not suitable for many small writes, only
// for few large writes. Use NewBufferedWriter instead, which is efficient
// regardless of the frequency and shape of the writes, and remember to Close
// that Writer when done.
func NewWriter(w io.Writer) *Writer {
return &Writer{
w: w,
obuf: make([]byte, obufLen),
}
}
// NewBufferedWriter returns a new Writer that compresses to w, using the
// framing format described at
// https://github.com/google/snappy/blob/master/framing_format.txt
//
// The Writer returned buffers writes. Users must call Close to guarantee all
// data has been forwarded to the underlying io.Writer. They may also call
// Flush zero or more times before calling Close.
func NewBufferedWriter(w io.Writer) *Writer {
return &Writer{
w: w,
ibuf: make([]byte, 0, maxBlockSize),
obuf: make([]byte, obufLen),
}
}
// Writer is an io.Writer than can write Snappy-compressed bytes.
type Writer struct {
w io.Writer
err error
// ibuf is a buffer for the incoming (uncompressed) bytes.
//
// Its use is optional. For backwards compatibility, Writers created by the
// NewWriter function have ibuf == nil, do not buffer incoming bytes, and
// therefore do not need to be Flush'ed or Close'd.
ibuf []byte
// obuf is a buffer for the outgoing (compressed) bytes.
obuf []byte
// wroteStreamHeader is whether we have written the stream header.
wroteStreamHeader bool
}
// Reset discards the writer's state and switches the Snappy writer to write to
// w. This permits reusing a Writer rather than allocating a new one.
func (w *Writer) Reset(writer io.Writer) {
w.w = writer
w.err = nil
if w.ibuf != nil {
w.ibuf = w.ibuf[:0]
}
w.wroteStreamHeader = false
}
// Write satisfies the io.Writer interface.
func (w *Writer) Write(p []byte) (nRet int, errRet error) {
if w.ibuf == nil {
// Do not buffer incoming bytes. This does not perform or compress well
// if the caller of Writer.Write writes many small slices. This
// behavior is therefore deprecated, but still supported for backwards
// compatibility with code that doesn't explicitly Flush or Close.
return w.write(p)
}
// The remainder of this method is based on bufio.Writer.Write from the
// standard library.
for len(p) > (cap(w.ibuf)-len(w.ibuf)) && w.err == nil {
var n int
if len(w.ibuf) == 0 {
// Large write, empty buffer.
// Write directly from p to avoid copy.
n, _ = w.write(p)
} else {
n = copy(w.ibuf[len(w.ibuf):cap(w.ibuf)], p)
w.ibuf = w.ibuf[:len(w.ibuf)+n]
w.Flush()
}
nRet += n
p = p[n:]
}
if w.err != nil {
return nRet, w.err
}
n := copy(w.ibuf[len(w.ibuf):cap(w.ibuf)], p)
w.ibuf = w.ibuf[:len(w.ibuf)+n]
nRet += n
return nRet, nil
}
func (w *Writer) write(p []byte) (nRet int, errRet error) {
if w.err != nil {
return 0, w.err
}
for len(p) > 0 {
obufStart := len(magicChunk)
if !w.wroteStreamHeader {
w.wroteStreamHeader = true
copy(w.obuf, magicChunk)
obufStart = 0
}
var uncompressed []byte
if len(p) > maxBlockSize {
uncompressed, p = p[:maxBlockSize], p[maxBlockSize:]
} else {
uncompressed, p = p, nil
}
checksum := crc(uncompressed)
// Compress the buffer, discarding the result if the improvement
// isn't at least 12.5%.
compressed := Encode(w.obuf[obufHeaderLen:], uncompressed)
chunkType := uint8(chunkTypeCompressedData)
chunkLen := 4 + len(compressed)
obufEnd := obufHeaderLen + len(compressed)
if len(compressed) >= len(uncompressed)-len(uncompressed)/8 {
chunkType = chunkTypeUncompressedData
chunkLen = 4 + len(uncompressed)
obufEnd = obufHeaderLen
}
// Fill in the per-chunk header that comes before the body.
w.obuf[len(magicChunk)+0] = chunkType
w.obuf[len(magicChunk)+1] = uint8(chunkLen >> 0)
w.obuf[len(magicChunk)+2] = uint8(chunkLen >> 8)
w.obuf[len(magicChunk)+3] = uint8(chunkLen >> 16)
w.obuf[len(magicChunk)+4] = uint8(checksum >> 0)
w.obuf[len(magicChunk)+5] = uint8(checksum >> 8)
w.obuf[len(magicChunk)+6] = uint8(checksum >> 16)
w.obuf[len(magicChunk)+7] = uint8(checksum >> 24)
if _, err := w.w.Write(w.obuf[obufStart:obufEnd]); err != nil {
w.err = err
return nRet, err
}
if chunkType == chunkTypeUncompressedData {
if _, err := w.w.Write(uncompressed); err != nil {
w.err = err
return nRet, err
}
}
nRet += len(uncompressed)
}
return nRet, nil
}
// Flush flushes the Writer to its underlying io.Writer.
func (w *Writer) Flush() error {
if w.err != nil {
return w.err
}
if len(w.ibuf) == 0 {
return nil
}
w.write(w.ibuf)
w.ibuf = w.ibuf[:0]
return w.err
}
// Close calls Flush and then closes the Writer.
func (w *Writer) Close() error {
w.Flush()
ret := w.err
if w.err == nil {
w.err = errClosed
}
return ret
}
vendor/github.com/golang/snappy/encode_amd64.go
Generated Vendored
+29
View File
@@ -0,0 +1,29 @@
// Copyright 2016 The Snappy-Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !appengine
// +build gc
// +build !noasm
package snappy
// emitLiteral has the same semantics as in encode_other.go.
//
//go:noescape
func emitLiteral(dst, lit []byte) int
// emitCopy has the same semantics as in encode_other.go.
//
//go:noescape
func emitCopy(dst []byte, offset, length int) int
// extendMatch has the same semantics as in encode_other.go.
//
//go:noescape
func extendMatch(src []byte, i, j int) int
// encodeBlock has the same semantics as in encode_other.go.
//
//go:noescape
func encodeBlock(dst, src []byte) (d int)
vendor/github.com/golang/snappy/encode_amd64.s
Generated Vendored
+730
View File
@@ -0,0 +1,730 @@
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !appengine
// +build gc
// +build !noasm
#include "textflag.h"
// The XXX lines assemble on Go 1.4, 1.5 and 1.7, but not 1.6, due to a
// Go toolchain regression. See https://github.com/golang/go/issues/15426 and
// https://github.com/golang/snappy/issues/29
//
// As a workaround, the package was built with a known good assembler, and
// those instructions were disassembled by "objdump -d" to yield the
// 4e 0f b7 7c 5c 78 movzwq 0x78(%rsp,%r11,2),%r15
// style comments, in AT&T asm syntax. Note that rsp here is a physical
// register, not Go/asm's SP pseudo-register (see https://golang.org/doc/asm).
// The instructions were then encoded as "BYTE $0x.." sequences, which assemble
// fine on Go 1.6.
// The asm code generally follows the pure Go code in encode_other.go, except
// where marked with a "!!!".
// ----------------------------------------------------------------------------
// func emitLiteral(dst, lit []byte) int
//
// All local variables fit into registers. The register allocation:
// - AX len(lit)
// - BX n
// - DX return value
// - DI &dst[i]
// - R10 &lit[0]
//
// The 24 bytes of stack space is to call runtime·memmove.
//
// The unusual register allocation of local variables, such as R10 for the
// source pointer, matches the allocation used at the call site in encodeBlock,
// which makes it easier to manually inline this function.
TEXT ·emitLiteral(SB), NOSPLIT, $24-56
MOVQ dst_base+0(FP), DI
MOVQ lit_base+24(FP), R10
MOVQ lit_len+32(FP), AX
MOVQ AX, DX
MOVL AX, BX
SUBL $1, BX
CMPL BX, $60
JLT oneByte
CMPL BX, $256
JLT twoBytes
threeBytes:
MOVB $0xf4, 0(DI)
MOVW BX, 1(DI)
ADDQ $3, DI
ADDQ $3, DX
JMP memmove
twoBytes:
MOVB $0xf0, 0(DI)
MOVB BX, 1(DI)
ADDQ $2, DI
ADDQ $2, DX
JMP memmove
oneByte:
SHLB $2, BX
MOVB BX, 0(DI)
ADDQ $1, DI
ADDQ $1, DX
memmove:
MOVQ DX, ret+48(FP)
// copy(dst[i:], lit)
//
// This means calling runtime·memmove(&dst[i], &lit[0], len(lit)), so we push
// DI, R10 and AX as arguments.
MOVQ DI, 0(SP)
MOVQ R10, 8(SP)
MOVQ AX, 16(SP)
CALL runtime·memmove(SB)
RET
// ----------------------------------------------------------------------------
// func emitCopy(dst []byte, offset, length int) int
//
// All local variables fit into registers. The register allocation:
// - AX length
// - SI &dst[0]
// - DI &dst[i]
// - R11 offset
//
// The unusual register allocation of local variables, such as R11 for the
// offset, matches the allocation used at the call site in encodeBlock, which
// makes it easier to manually inline this function.
TEXT ·emitCopy(SB), NOSPLIT, $0-48
MOVQ dst_base+0(FP), DI
MOVQ DI, SI
MOVQ offset+24(FP), R11
MOVQ length+32(FP), AX
loop0:
// for length >= 68 { etc }
CMPL AX, $68
JLT step1
// Emit a length 64 copy, encoded as 3 bytes.
MOVB $0xfe, 0(DI)
MOVW R11, 1(DI)
ADDQ $3, DI
SUBL $64, AX
JMP loop0
step1:
// if length > 64 { etc }
CMPL AX, $64
JLE step2
// Emit a length 60 copy, encoded as 3 bytes.
MOVB $0xee, 0(DI)
MOVW R11, 1(DI)
ADDQ $3, DI
SUBL $60, AX
step2:
// if length >= 12 || offset >= 2048 { goto step3 }
CMPL AX, $12
JGE step3
CMPL R11, $2048
JGE step3
// Emit the remaining copy, encoded as 2 bytes.
MOVB R11, 1(DI)
SHRL $8, R11
SHLB $5, R11
SUBB $4, AX
SHLB $2, AX
ORB AX, R11
ORB $1, R11
MOVB R11, 0(DI)
ADDQ $2, DI
// Return the number of bytes written.
SUBQ SI, DI
MOVQ DI, ret+40(FP)
RET
step3:
// Emit the remaining copy, encoded as 3 bytes.
SUBL $1, AX
SHLB $2, AX
ORB $2, AX
MOVB AX, 0(DI)
MOVW R11, 1(DI)
ADDQ $3, DI
// Return the number of bytes written.
SUBQ SI, DI
MOVQ DI, ret+40(FP)
RET
// ----------------------------------------------------------------------------
// func extendMatch(src []byte, i, j int) int
//
// All local variables fit into registers. The register allocation:
// - DX &src[0]
// - SI &src[j]
// - R13 &src[len(src) - 8]
// - R14 &src[len(src)]
// - R15 &src[i]
//
// The unusual register allocation of local variables, such as R15 for a source
// pointer, matches the allocation used at the call site in encodeBlock, which
// makes it easier to manually inline this function.
TEXT ·extendMatch(SB), NOSPLIT, $0-48
MOVQ src_base+0(FP), DX
MOVQ src_len+8(FP), R14
MOVQ i+24(FP), R15
MOVQ j+32(FP), SI
ADDQ DX, R14
ADDQ DX, R15
ADDQ DX, SI
MOVQ R14, R13
SUBQ $8, R13
cmp8:
// As long as we are 8 or more bytes before the end of src, we can load and
// compare 8 bytes at a time. If those 8 bytes are equal, repeat.
CMPQ SI, R13
JA cmp1
MOVQ (R15), AX
MOVQ (SI), BX
CMPQ AX, BX
JNE bsf
ADDQ $8, R15
ADDQ $8, SI
JMP cmp8
bsf:
// If those 8 bytes were not equal, XOR the two 8 byte values, and return
// the index of the first byte that differs. The BSF instruction finds the
// least significant 1 bit, the amd64 architecture is little-endian, and
// the shift by 3 converts a bit index to a byte index.
XORQ AX, BX
BSFQ BX, BX
SHRQ $3, BX
ADDQ BX, SI
// Convert from &src[ret] to ret.
SUBQ DX, SI
MOVQ SI, ret+40(FP)
RET
cmp1:
// In src's tail, compare 1 byte at a time.
CMPQ SI, R14
JAE extendMatchEnd
MOVB (R15), AX
MOVB (SI), BX
CMPB AX, BX
JNE extendMatchEnd
ADDQ $1, R15
ADDQ $1, SI
JMP cmp1
extendMatchEnd:
// Convert from &src[ret] to ret.
SUBQ DX, SI
MOVQ SI, ret+40(FP)
RET
// ----------------------------------------------------------------------------
// func encodeBlock(dst, src []byte) (d int)
//
// All local variables fit into registers, other than "var table". The register
// allocation:
// - AX . .
// - BX . .
// - CX 56 shift (note that amd64 shifts by non-immediates must use CX).
// - DX 64 &src[0], tableSize
// - SI 72 &src[s]
// - DI 80 &dst[d]
// - R9 88 sLimit
// - R10 . &src[nextEmit]
// - R11 96 prevHash, currHash, nextHash, offset
// - R12 104 &src[base], skip
// - R13 . &src[nextS], &src[len(src) - 8]
// - R14 . len(src), bytesBetweenHashLookups, &src[len(src)], x
// - R15 112 candidate
//
// The second column (56, 64, etc) is the stack offset to spill the registers
// when calling other functions. We could pack this slightly tighter, but it's
// simpler to have a dedicated spill map independent of the function called.
//
// "var table [maxTableSize]uint16" takes up 32768 bytes of stack space. An
// extra 56 bytes, to call other functions, and an extra 64 bytes, to spill
// local variables (registers) during calls gives 32768 + 56 + 64 = 32888.
TEXT ·encodeBlock(SB), 0, $32888-56
MOVQ dst_base+0(FP), DI
MOVQ src_base+24(FP), SI
MOVQ src_len+32(FP), R14
// shift, tableSize := uint32(32-8), 1<<8
MOVQ $24, CX
MOVQ $256, DX
calcShift:
// for ; tableSize < maxTableSize && tableSize < len(src); tableSize *= 2 {
// shift--
// }
CMPQ DX, $16384
JGE varTable
CMPQ DX, R14
JGE varTable
SUBQ $1, CX
SHLQ $1, DX
JMP calcShift
varTable:
// var table [maxTableSize]uint16
//
// In the asm code, unlike the Go code, we can zero-initialize only the
// first tableSize elements. Each uint16 element is 2 bytes and each MOVOU
// writes 16 bytes, so we can do only tableSize/8 writes instead of the
// 2048 writes that would zero-initialize all of table's 32768 bytes.
SHRQ $3, DX
LEAQ table-32768(SP), BX
PXOR X0, X0
memclr:
MOVOU X0, 0(BX)
ADDQ $16, BX
SUBQ $1, DX
JNZ memclr
// !!! DX = &src[0]
MOVQ SI, DX
// sLimit := len(src) - inputMargin
MOVQ R14, R9
SUBQ $15, R9
// !!! Pre-emptively spill CX, DX and R9 to the stack. Their values don't
// change for the rest of the function.
MOVQ CX, 56(SP)
MOVQ DX, 64(SP)
MOVQ R9, 88(SP)
// nextEmit := 0
MOVQ DX, R10
// s := 1
ADDQ $1, SI
// nextHash := hash(load32(src, s), shift)
MOVL 0(SI), R11
IMULL $0x1e35a7bd, R11
SHRL CX, R11
outer:
// for { etc }
// skip := 32
MOVQ $32, R12
// nextS := s
MOVQ SI, R13
// candidate := 0
MOVQ $0, R15
inner0:
// for { etc }
// s := nextS
MOVQ R13, SI
// bytesBetweenHashLookups := skip >> 5
MOVQ R12, R14
SHRQ $5, R14
// nextS = s + bytesBetweenHashLookups
ADDQ R14, R13
// skip += bytesBetweenHashLookups
ADDQ R14, R12
// if nextS > sLimit { goto emitRemainder }
MOVQ R13, AX
SUBQ DX, AX
CMPQ AX, R9
JA emitRemainder
// candidate = int(table[nextHash])
// XXX: MOVWQZX table-32768(SP)(R11*2), R15
// XXX: 4e 0f b7 7c 5c 78 movzwq 0x78(%rsp,%r11,2),%r15
BYTE $0x4e
BYTE $0x0f
BYTE $0xb7
BYTE $0x7c
BYTE $0x5c
BYTE $0x78
// table[nextHash] = uint16(s)
MOVQ SI, AX
SUBQ DX, AX
// XXX: MOVW AX, table-32768(SP)(R11*2)
// XXX: 66 42 89 44 5c 78 mov %ax,0x78(%rsp,%r11,2)
BYTE $0x66
BYTE $0x42
BYTE $0x89
BYTE $0x44
BYTE $0x5c
BYTE $0x78
// nextHash = hash(load32(src, nextS), shift)
MOVL 0(R13), R11
IMULL $0x1e35a7bd, R11
SHRL CX, R11
// if load32(src, s) != load32(src, candidate) { continue } break
MOVL 0(SI), AX
MOVL (DX)(R15*1), BX
CMPL AX, BX
JNE inner0
fourByteMatch:
// As per the encode_other.go code:
//
// A 4-byte match has been found. We'll later see etc.
// !!! Jump to a fast path for short (<= 16 byte) literals. See the comment
// on inputMargin in encode.go.
MOVQ SI, AX
SUBQ R10, AX
CMPQ AX, $16
JLE emitLiteralFastPath
// ----------------------------------------
// Begin inline of the emitLiteral call.
//
// d += emitLiteral(dst[d:], src[nextEmit:s])
MOVL AX, BX
SUBL $1, BX
CMPL BX, $60
JLT inlineEmitLiteralOneByte
CMPL BX, $256
JLT inlineEmitLiteralTwoBytes
inlineEmitLiteralThreeBytes:
MOVB $0xf4, 0(DI)
MOVW BX, 1(DI)
ADDQ $3, DI
JMP inlineEmitLiteralMemmove
inlineEmitLiteralTwoBytes:
MOVB $0xf0, 0(DI)
MOVB BX, 1(DI)
ADDQ $2, DI
JMP inlineEmitLiteralMemmove
inlineEmitLiteralOneByte:
SHLB $2, BX
MOVB BX, 0(DI)
ADDQ $1, DI
inlineEmitLiteralMemmove:
// Spill local variables (registers) onto the stack; call; unspill.
//
// copy(dst[i:], lit)
//
// This means calling runtime·memmove(&dst[i], &lit[0], len(lit)), so we push
// DI, R10 and AX as arguments.
MOVQ DI, 0(SP)
MOVQ R10, 8(SP)
MOVQ AX, 16(SP)
ADDQ AX, DI // Finish the "d +=" part of "d += emitLiteral(etc)".
MOVQ SI, 72(SP)
MOVQ DI, 80(SP)
MOVQ R15, 112(SP)
CALL runtime·memmove(SB)
MOVQ 56(SP), CX
MOVQ 64(SP), DX
MOVQ 72(SP), SI
MOVQ 80(SP), DI
MOVQ 88(SP), R9
MOVQ 112(SP), R15
JMP inner1
inlineEmitLiteralEnd:
// End inline of the emitLiteral call.
// ----------------------------------------
emitLiteralFastPath:
// !!! Emit the 1-byte encoding "uint8(len(lit)-1)<<2".
MOVB AX, BX
SUBB $1, BX
SHLB $2, BX
MOVB BX, (DI)
ADDQ $1, DI
// !!! Implement the copy from lit to dst as a 16-byte load and store.
// (Encode's documentation says that dst and src must not overlap.)
//
// This always copies 16 bytes, instead of only len(lit) bytes, but that's
// OK. Subsequent iterations will fix up the overrun.
//
// Note that on amd64, it is legal and cheap to issue unaligned 8-byte or
// 16-byte loads and stores. This technique probably wouldn't be as
// effective on architectures that are fussier about alignment.
MOVOU 0(R10), X0
MOVOU X0, 0(DI)
ADDQ AX, DI
inner1:
// for { etc }
// base := s
MOVQ SI, R12
// !!! offset := base - candidate
MOVQ R12, R11
SUBQ R15, R11
SUBQ DX, R11
// ----------------------------------------
// Begin inline of the extendMatch call.
//
// s = extendMatch(src, candidate+4, s+4)
// !!! R14 = &src[len(src)]
MOVQ src_len+32(FP), R14
ADDQ DX, R14
// !!! R13 = &src[len(src) - 8]
MOVQ R14, R13
SUBQ $8, R13
// !!! R15 = &src[candidate + 4]
ADDQ $4, R15
ADDQ DX, R15
// !!! s += 4
ADDQ $4, SI
inlineExtendMatchCmp8:
// As long as we are 8 or more bytes before the end of src, we can load and
// compare 8 bytes at a time. If those 8 bytes are equal, repeat.
CMPQ SI, R13
JA inlineExtendMatchCmp1
MOVQ (R15), AX
MOVQ (SI), BX
CMPQ AX, BX
JNE inlineExtendMatchBSF
ADDQ $8, R15
ADDQ $8, SI
JMP inlineExtendMatchCmp8
inlineExtendMatchBSF:
// If those 8 bytes were not equal, XOR the two 8 byte values, and return
// the index of the first byte that differs. The BSF instruction finds the
// least significant 1 bit, the amd64 architecture is little-endian, and
// the shift by 3 converts a bit index to a byte index.
XORQ AX, BX
BSFQ BX, BX
SHRQ $3, BX
ADDQ BX, SI
JMP inlineExtendMatchEnd
inlineExtendMatchCmp1:
// In src's tail, compare 1 byte at a time.
CMPQ SI, R14
JAE inlineExtendMatchEnd
MOVB (R15), AX
MOVB (SI), BX
CMPB AX, BX
JNE inlineExtendMatchEnd
ADDQ $1, R15
ADDQ $1, SI
JMP inlineExtendMatchCmp1
inlineExtendMatchEnd:
// End inline of the extendMatch call.
// ----------------------------------------
// ----------------------------------------
// Begin inline of the emitCopy call.
//
// d += emitCopy(dst[d:], base-candidate, s-base)
// !!! length := s - base
MOVQ SI, AX
SUBQ R12, AX
inlineEmitCopyLoop0:
// for length >= 68 { etc }
CMPL AX, $68
JLT inlineEmitCopyStep1
// Emit a length 64 copy, encoded as 3 bytes.
MOVB $0xfe, 0(DI)
MOVW R11, 1(DI)
ADDQ $3, DI
SUBL $64, AX
JMP inlineEmitCopyLoop0
inlineEmitCopyStep1:
// if length > 64 { etc }
CMPL AX, $64
JLE inlineEmitCopyStep2
// Emit a length 60 copy, encoded as 3 bytes.
MOVB $0xee, 0(DI)
MOVW R11, 1(DI)
ADDQ $3, DI
SUBL $60, AX
inlineEmitCopyStep2:
// if length >= 12 || offset >= 2048 { goto inlineEmitCopyStep3 }
CMPL AX, $12
JGE inlineEmitCopyStep3
CMPL R11, $2048
JGE inlineEmitCopyStep3
// Emit the remaining copy, encoded as 2 bytes.
MOVB R11, 1(DI)
SHRL $8, R11
SHLB $5, R11
SUBB $4, AX
SHLB $2, AX
ORB AX, R11
ORB $1, R11
MOVB R11, 0(DI)
ADDQ $2, DI
JMP inlineEmitCopyEnd
inlineEmitCopyStep3:
// Emit the remaining copy, encoded as 3 bytes.
SUBL $1, AX
SHLB $2, AX
ORB $2, AX
MOVB AX, 0(DI)
MOVW R11, 1(DI)
ADDQ $3, DI
inlineEmitCopyEnd:
// End inline of the emitCopy call.
// ----------------------------------------
// nextEmit = s
MOVQ SI, R10
// if s >= sLimit { goto emitRemainder }
MOVQ SI, AX
SUBQ DX, AX
CMPQ AX, R9
JAE emitRemainder
// As per the encode_other.go code:
//
// We could immediately etc.
// x := load64(src, s-1)
MOVQ -1(SI), R14
// prevHash := hash(uint32(x>>0), shift)
MOVL R14, R11
IMULL $0x1e35a7bd, R11
SHRL CX, R11
// table[prevHash] = uint16(s-1)
MOVQ SI, AX
SUBQ DX, AX
SUBQ $1, AX
// XXX: MOVW AX, table-32768(SP)(R11*2)
// XXX: 66 42 89 44 5c 78 mov %ax,0x78(%rsp,%r11,2)
BYTE $0x66
BYTE $0x42
BYTE $0x89
BYTE $0x44
BYTE $0x5c
BYTE $0x78
// currHash := hash(uint32(x>>8), shift)
SHRQ $8, R14
MOVL R14, R11
IMULL $0x1e35a7bd, R11
SHRL CX, R11
// candidate = int(table[currHash])
// XXX: MOVWQZX table-32768(SP)(R11*2), R15
// XXX: 4e 0f b7 7c 5c 78 movzwq 0x78(%rsp,%r11,2),%r15
BYTE $0x4e
BYTE $0x0f
BYTE $0xb7
BYTE $0x7c
BYTE $0x5c
BYTE $0x78
// table[currHash] = uint16(s)
ADDQ $1, AX
// XXX: MOVW AX, table-32768(SP)(R11*2)
// XXX: 66 42 89 44 5c 78 mov %ax,0x78(%rsp,%r11,2)
BYTE $0x66
BYTE $0x42
BYTE $0x89
BYTE $0x44
BYTE $0x5c
BYTE $0x78
// if uint32(x>>8) == load32(src, candidate) { continue }
MOVL (DX)(R15*1), BX
CMPL R14, BX
JEQ inner1
// nextHash = hash(uint32(x>>16), shift)
SHRQ $8, R14
MOVL R14, R11
IMULL $0x1e35a7bd, R11
SHRL CX, R11
// s++
ADDQ $1, SI
// break out of the inner1 for loop, i.e. continue the outer loop.
JMP outer
emitRemainder:
// if nextEmit < len(src) { etc }
MOVQ src_len+32(FP), AX
ADDQ DX, AX
CMPQ R10, AX
JEQ encodeBlockEnd
// d += emitLiteral(dst[d:], src[nextEmit:])
//
// Push args.
MOVQ DI, 0(SP)
MOVQ $0, 8(SP) // Unnecessary, as the callee ignores it, but conservative.
MOVQ $0, 16(SP) // Unnecessary, as the callee ignores it, but conservative.
MOVQ R10, 24(SP)
SUBQ R10, AX
MOVQ AX, 32(SP)
MOVQ AX, 40(SP) // Unnecessary, as the callee ignores it, but conservative.
// Spill local variables (registers) onto the stack; call; unspill.
MOVQ DI, 80(SP)
CALL ·emitLiteral(SB)
MOVQ 80(SP), DI
// Finish the "d +=" part of "d += emitLiteral(etc)".
ADDQ 48(SP), DI
encodeBlockEnd:
MOVQ dst_base+0(FP), AX
SUBQ AX, DI
MOVQ DI, d+48(FP)
RET
vendor/github.com/golang/snappy/snappy.go
Generated Vendored
+87
View File
@@ -0,0 +1,87 @@
// Copyright 2011 The Snappy-Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package snappy implements the snappy block-based compression format.
// It aims for very high speeds and reasonable compression.
//
// The C++ snappy implementation is at https://github.com/google/snappy
package snappy // import "github.com/golang/snappy"
import (
"hash/crc32"
)
/*
Each encoded block begins with the varint-encoded length of the decoded data,
followed by a sequence of chunks. Chunks begin and end on byte boundaries. The
first byte of each chunk is broken into its 2 least and 6 most significant bits
called l and m: l ranges in [0, 4) and m ranges in [0, 64). l is the chunk tag.
Zero means a literal tag. All other values mean a copy tag.
For literal tags:
- If m < 60, the next 1 + m bytes are literal bytes.
- Otherwise, let n be the little-endian unsigned integer denoted by the next
m - 59 bytes. The next 1 + n bytes after that are literal bytes.
For copy tags, length bytes are copied from offset bytes ago, in the style of
Lempel-Ziv compression algorithms. In particular:
- For l == 1, the offset ranges in [0, 1<<11) and the length in [4, 12).
The length is 4 + the low 3 bits of m. The high 3 bits of m form bits 8-10
of the offset. The next byte is bits 0-7 of the offset.
- For l == 2, the offset ranges in [0, 1<<16) and the length in [1, 65).
The length is 1 + m. The offset is the little-endian unsigned integer
denoted by the next 2 bytes.
- For l == 3, this tag is a legacy format that is no longer issued by most
encoders. Nonetheless, the offset ranges in [0, 1<<32) and the length in
[1, 65). The length is 1 + m. The offset is the little-endian unsigned
integer denoted by the next 4 bytes.
*/
const (
tagLiteral = 0x00
tagCopy1 = 0x01
tagCopy2 = 0x02
tagCopy4 = 0x03
)
const (
checksumSize = 4
chunkHeaderSize = 4
magicChunk = "\xff\x06\x00\x00" + magicBody
magicBody = "sNaPpY"
// maxBlockSize is the maximum size of the input to encodeBlock. It is not
// part of the wire format per se, but some parts of the encoder assume
// that an offset fits into a uint16.
//
// Also, for the framing format (Writer type instead of Encode function),
// https://github.com/google/snappy/blob/master/framing_format.txt says
// that "the uncompressed data in a chunk must be no longer than 65536
// bytes".
maxBlockSize = 65536
// maxEncodedLenOfMaxBlockSize equals MaxEncodedLen(maxBlockSize), but is
// hard coded to be a const instead of a variable, so that obufLen can also
// be a const. Their equivalence is confirmed by
// TestMaxEncodedLenOfMaxBlockSize.
maxEncodedLenOfMaxBlockSize = 76490
obufHeaderLen = len(magicChunk) + checksumSize + chunkHeaderSize
obufLen = obufHeaderLen + maxEncodedLenOfMaxBlockSize
)
const (
chunkTypeCompressedData = 0x00
chunkTypeUncompressedData = 0x01
chunkTypePadding = 0xfe
chunkTypeStreamIdentifier = 0xff
)
var crcTable = crc32.MakeTable(crc32.Castagnoli)
// crc implements the checksum specified in section 3 of
// https://github.com/google/snappy/blob/master/framing_format.txt
func crc(b []byte) uint32 {
c := crc32.Update(0, crcTable, b)
return uint32(c>>15|c<<17) + 0xa282ead8
}
vendor/github.com/klauspost/crc32/LICENSE
Generated Vendored
+28
View File
@@ -0,0 +1,28 @@
Copyright (c) 2012 The Go Authors. All rights reserved.
Copyright (c) 2015 Klaus Post
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above
copyright notice, this list of conditions and the following disclaimer
in the documentation and/or other materials provided with the
distribution.
* Neither the name of Google Inc. nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
vendor/github.com/klauspost/crc32/README.md
Generated Vendored
+87
View File
@@ -0,0 +1,87 @@
# crc32
CRC32 hash with x64 optimizations
This package is a drop-in replacement for the standard library `hash/crc32` package, that features SSE 4.2 optimizations on x64 platforms, for a 10x speedup.
[![Build Status](https://travis-ci.org/klauspost/crc32.svg?branch=master)](https://travis-ci.org/klauspost/crc32)
# usage
Install using `go get github.com/klauspost/crc32`. This library is based on Go 1.5 code and requires Go 1.3 or newer.
Replace `import "hash/crc32"` with `import "github.com/klauspost/crc32"` and you are good to go.
# changes
* Oct 20, 2016: Changes have been merged to upstream Go. Package updated to match.
* Dec 4, 2015: Uses the "slice-by-8" trick more extensively, which gives a 1.5 to 2.5x speedup if assembler is unavailable.
# performance
For *Go 1.7* performance is equivalent to the standard library. So if you use this package for Go 1.7 you can switch back.
For IEEE tables (the most common), there is approximately a factor 10 speedup with "CLMUL" (Carryless multiplication) instruction:
```
benchmark old ns/op new ns/op delta
BenchmarkCrc32KB 99955 10258 -89.74%
benchmark old MB/s new MB/s speedup
BenchmarkCrc32KB 327.83 3194.20 9.74x
```
For other tables and "CLMUL" capable machines the performance is the same as the standard library.
Here are some detailed benchmarks, comparing to go 1.5 standard library with and without assembler enabled.
```
Std: Standard Go 1.5 library
Crc: Indicates IEEE type CRC.
40B: Size of each slice encoded.
NoAsm: Assembler was disabled (ie. not an AMD64 or SSE 4.2+ capable machine).
Castagnoli: Castagnoli CRC type.
BenchmarkStdCrc40B-4 10000000 158 ns/op 252.88 MB/s
BenchmarkCrc40BNoAsm-4 20000000 105 ns/op 377.38 MB/s (slice8)
BenchmarkCrc40B-4 20000000 105 ns/op 378.77 MB/s (slice8)
BenchmarkStdCrc1KB-4 500000 3604 ns/op 284.10 MB/s
BenchmarkCrc1KBNoAsm-4 1000000 1463 ns/op 699.79 MB/s (slice8)
BenchmarkCrc1KB-4 3000000 396 ns/op 2583.69 MB/s (asm)
BenchmarkStdCrc8KB-4 200000 11417 ns/op 717.48 MB/s (slice8)
BenchmarkCrc8KBNoAsm-4 200000 11317 ns/op 723.85 MB/s (slice8)
BenchmarkCrc8KB-4 500000 2919 ns/op 2805.73 MB/s (asm)
BenchmarkStdCrc32KB-4 30000 45749 ns/op 716.24 MB/s (slice8)
BenchmarkCrc32KBNoAsm-4 30000 45109 ns/op 726.42 MB/s (slice8)
BenchmarkCrc32KB-4 100000 11497 ns/op 2850.09 MB/s (asm)
BenchmarkStdNoAsmCastagnol40B-4 10000000 161 ns/op 246.94 MB/s
BenchmarkStdCastagnoli40B-4 50000000 28.4 ns/op 1410.69 MB/s (asm)
BenchmarkCastagnoli40BNoAsm-4 20000000 100 ns/op 398.01 MB/s (slice8)
BenchmarkCastagnoli40B-4 50000000 28.2 ns/op 1419.54 MB/s (asm)
BenchmarkStdNoAsmCastagnoli1KB-4 500000 3622 ns/op 282.67 MB/s
BenchmarkStdCastagnoli1KB-4 10000000 144 ns/op 7099.78 MB/s (asm)
BenchmarkCastagnoli1KBNoAsm-4 1000000 1475 ns/op 694.14 MB/s (slice8)
BenchmarkCastagnoli1KB-4 10000000 146 ns/op 6993.35 MB/s (asm)
BenchmarkStdNoAsmCastagnoli8KB-4 50000 28781 ns/op 284.63 MB/s
BenchmarkStdCastagnoli8KB-4 1000000 1029 ns/op 7957.89 MB/s (asm)
BenchmarkCastagnoli8KBNoAsm-4 200000 11410 ns/op 717.94 MB/s (slice8)
BenchmarkCastagnoli8KB-4 1000000 1000 ns/op 8188.71 MB/s (asm)
BenchmarkStdNoAsmCastagnoli32KB-4 10000 115426 ns/op 283.89 MB/s
BenchmarkStdCastagnoli32KB-4 300000 4065 ns/op 8059.13 MB/s (asm)
BenchmarkCastagnoli32KBNoAsm-4 30000 45171 ns/op 725.41 MB/s (slice8)
BenchmarkCastagnoli32KB-4 500000 4077 ns/op 8035.89 MB/s (asm)
```
The IEEE assembler optimizations has been submitted and will be part of the Go 1.6 standard library.
However, the improved use of slice-by-8 has not, but will probably be submitted for Go 1.7.
# license
Standard Go license. Changes are Copyright (c) 2015 Klaus Post under same conditions.
vendor/github.com/klauspost/crc32/crc32.go
Generated Vendored
+207
View File
@@ -0,0 +1,207 @@
// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package crc32 implements the 32-bit cyclic redundancy check, or CRC-32,
// checksum. See http://en.wikipedia.org/wiki/Cyclic_redundancy_check for
// information.
//
// Polynomials are represented in LSB-first form also known as reversed representation.
//
// See http://en.wikipedia.org/wiki/Mathematics_of_cyclic_redundancy_checks#Reversed_representations_and_reciprocal_polynomials
// for information.
package crc32
import (
"hash"
"sync"
)
// The size of a CRC-32 checksum in bytes.
const Size = 4
// Predefined polynomials.
const (
// IEEE is by far and away the most common CRC-32 polynomial.
// Used by ethernet (IEEE 802.3), v.42, fddi, gzip, zip, png, ...
IEEE = 0xedb88320
// Castagnoli's polynomial, used in iSCSI.
// Has better error detection characteristics than IEEE.
// http://dx.doi.org/10.1109/26.231911
Castagnoli = 0x82f63b78
// Koopman's polynomial.
// Also has better error detection characteristics than IEEE.
// http://dx.doi.org/10.1109/DSN.2002.1028931
Koopman = 0xeb31d82e
)
// Table is a 256-word table representing the polynomial for efficient processing.
type Table [256]uint32
// This file makes use of functions implemented in architecture-specific files.
// The interface that they implement is as follows:
//
// // archAvailableIEEE reports whether an architecture-specific CRC32-IEEE
// // algorithm is available.
// archAvailableIEEE() bool
//
// // archInitIEEE initializes the architecture-specific CRC3-IEEE algorithm.
// // It can only be called if archAvailableIEEE() returns true.
// archInitIEEE()
//
// // archUpdateIEEE updates the given CRC32-IEEE. It can only be called if
// // archInitIEEE() was previously called.
// archUpdateIEEE(crc uint32, p []byte) uint32
//
// // archAvailableCastagnoli reports whether an architecture-specific
// // CRC32-C algorithm is available.
// archAvailableCastagnoli() bool
//
// // archInitCastagnoli initializes the architecture-specific CRC32-C
// // algorithm. It can only be called if archAvailableCastagnoli() returns
// // true.
// archInitCastagnoli()
//
// // archUpdateCastagnoli updates the given CRC32-C. It can only be called
// // if archInitCastagnoli() was previously called.
// archUpdateCastagnoli(crc uint32, p []byte) uint32
// castagnoliTable points to a lazily initialized Table for the Castagnoli
// polynomial. MakeTable will always return this value when asked to make a
// Castagnoli table so we can compare against it to find when the caller is
// using this polynomial.
var castagnoliTable *Table
var castagnoliTable8 *slicing8Table
var castagnoliArchImpl bool
var updateCastagnoli func(crc uint32, p []byte) uint32
var castagnoliOnce sync.Once
func castagnoliInit() {
castagnoliTable = simpleMakeTable(Castagnoli)
castagnoliArchImpl = archAvailableCastagnoli()
if castagnoliArchImpl {
archInitCastagnoli()
updateCastagnoli = archUpdateCastagnoli
} else {
// Initialize the slicing-by-8 table.
castagnoliTable8 = slicingMakeTable(Castagnoli)
updateCastagnoli = func(crc uint32, p []byte) uint32 {
return slicingUpdate(crc, castagnoliTable8, p)
}
}
}
// IEEETable is the table for the IEEE polynomial.
var IEEETable = simpleMakeTable(IEEE)
// ieeeTable8 is the slicing8Table for IEEE
var ieeeTable8 *slicing8Table
var ieeeArchImpl bool
var updateIEEE func(crc uint32, p []byte) uint32
var ieeeOnce sync.Once
func ieeeInit() {
ieeeArchImpl = archAvailableIEEE()
if ieeeArchImpl {
archInitIEEE()
updateIEEE = archUpdateIEEE
} else {
// Initialize the slicing-by-8 table.
ieeeTable8 = slicingMakeTable(IEEE)
updateIEEE = func(crc uint32, p []byte) uint32 {
return slicingUpdate(crc, ieeeTable8, p)
}
}
}
// MakeTable returns a Table constructed from the specified polynomial.
// The contents of this Table must not be modified.
func MakeTable(poly uint32) *Table {
switch poly {
case IEEE:
ieeeOnce.Do(ieeeInit)
return IEEETable
case Castagnoli:
castagnoliOnce.Do(castagnoliInit)
return castagnoliTable
}
return simpleMakeTable(poly)
}
// digest represents the partial evaluation of a checksum.
type digest struct {
crc uint32
tab *Table
}
// New creates a new hash.Hash32 computing the CRC-32 checksum
// using the polynomial represented by the Table.
// Its Sum method will lay the value out in big-endian byte order.
func New(tab *Table) hash.Hash32 {
if tab == IEEETable {
ieeeOnce.Do(ieeeInit)
}
return &digest{0, tab}
}
// NewIEEE creates a new hash.Hash32 computing the CRC-32 checksum
// using the IEEE polynomial.
// Its Sum method will lay the value out in big-endian byte order.
func NewIEEE() hash.Hash32 { return New(IEEETable) }
func (d *digest) Size() int { return Size }
func (d *digest) BlockSize() int { return 1 }
func (d *digest) Reset() { d.crc = 0 }
// Update returns the result of adding the bytes in p to the crc.
func Update(crc uint32, tab *Table, p []byte) uint32 {
switch tab {
case castagnoliTable:
return updateCastagnoli(crc, p)
case IEEETable:
// Unfortunately, because IEEETable is exported, IEEE may be used without a
// call to MakeTable. We have to make sure it gets initialized in that case.
ieeeOnce.Do(ieeeInit)
return updateIEEE(crc, p)
default:
return simpleUpdate(crc, tab, p)
}
}
func (d *digest) Write(p []byte) (n int, err error) {
switch d.tab {
case castagnoliTable:
d.crc = updateCastagnoli(d.crc, p)
case IEEETable:
// We only create digest objects through New() which takes care of
// initialization in this case.
d.crc = updateIEEE(d.crc, p)
default:
d.crc = simpleUpdate(d.crc, d.tab, p)
}
return len(p), nil
}
func (d *digest) Sum32() uint32 { return d.crc }
func (d *digest) Sum(in []byte) []byte {
s := d.Sum32()
return append(in, byte(s>>24), byte(s>>16), byte(s>>8), byte(s))
}
// Checksum returns the CRC-32 checksum of data
// using the polynomial represented by the Table.
func Checksum(data []byte, tab *Table) uint32 { return Update(0, tab, data) }
// ChecksumIEEE returns the CRC-32 checksum of data
// using the IEEE polynomial.
func ChecksumIEEE(data []byte) uint32 {
ieeeOnce.Do(ieeeInit)
return updateIEEE(0, data)
}
vendor/github.com/klauspost/crc32/crc32_amd64.go
Generated Vendored
+230
View File
@@ -0,0 +1,230 @@
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !appengine,!gccgo
// AMD64-specific hardware-assisted CRC32 algorithms. See crc32.go for a
// description of the interface that each architecture-specific file
// implements.
package crc32
import "unsafe"
// This file contains the code to call the SSE 4.2 version of the Castagnoli
// and IEEE CRC.
// haveSSE41/haveSSE42/haveCLMUL are defined in crc_amd64.s and use
// CPUID to test for SSE 4.1, 4.2 and CLMUL support.
func haveSSE41() bool
func haveSSE42() bool
func haveCLMUL() bool
// castagnoliSSE42 is defined in crc32_amd64.s and uses the SSE4.2 CRC32
// instruction.
//go:noescape
func castagnoliSSE42(crc uint32, p []byte) uint32
// castagnoliSSE42Triple is defined in crc32_amd64.s and uses the SSE4.2 CRC32
// instruction.
//go:noescape
func castagnoliSSE42Triple(
crcA, crcB, crcC uint32,
a, b, c []byte,
rounds uint32,
) (retA uint32, retB uint32, retC uint32)
// ieeeCLMUL is defined in crc_amd64.s and uses the PCLMULQDQ
// instruction as well as SSE 4.1.
//go:noescape
func ieeeCLMUL(crc uint32, p []byte) uint32
var sse42 = haveSSE42()
var useFastIEEE = haveCLMUL() && haveSSE41()
const castagnoliK1 = 168
const castagnoliK2 = 1344
type sse42Table [4]Table
var castagnoliSSE42TableK1 *sse42Table
var castagnoliSSE42TableK2 *sse42Table
func archAvailableCastagnoli() bool {
return sse42
}
func archInitCastagnoli() {
if !sse42 {
panic("arch-specific Castagnoli not available")
}
castagnoliSSE42TableK1 = new(sse42Table)
castagnoliSSE42TableK2 = new(sse42Table)
// See description in updateCastagnoli.
// t[0][i] = CRC(i000, O)
// t[1][i] = CRC(0i00, O)
// t[2][i] = CRC(00i0, O)
// t[3][i] = CRC(000i, O)
// where O is a sequence of K zeros.
var tmp [castagnoliK2]byte
for b := 0; b < 4; b++ {
for i := 0; i < 256; i++ {
val := uint32(i) << uint32(b*8)
castagnoliSSE42TableK1[b][i] = castagnoliSSE42(val, tmp[:castagnoliK1])
castagnoliSSE42TableK2[b][i] = castagnoliSSE42(val, tmp[:])
}
}
}
// castagnoliShift computes the CRC32-C of K1 or K2 zeroes (depending on the
// table given) with the given initial crc value. This corresponds to
// CRC(crc, O) in the description in updateCastagnoli.
func castagnoliShift(table *sse42Table, crc uint32) uint32 {
return table[3][crc>>24] ^
table[2][(crc>>16)&0xFF] ^
table[1][(crc>>8)&0xFF] ^
table[0][crc&0xFF]
}
func archUpdateCastagnoli(crc uint32, p []byte) uint32 {
if !sse42 {
panic("not available")
}
// This method is inspired from the algorithm in Intel's white paper:
// "Fast CRC Computation for iSCSI Polynomial Using CRC32 Instruction"
// The same strategy of splitting the buffer in three is used but the
// combining calculation is different; the complete derivation is explained
// below.
//
// -- The basic idea --
//
// The CRC32 instruction (available in SSE4.2) can process 8 bytes at a
// time. In recent Intel architectures the instruction takes 3 cycles;
// however the processor can pipeline up to three instructions if they
// don't depend on each other.
//
// Roughly this means that we can process three buffers in about the same
// time we can process one buffer.
//
// The idea is then to split the buffer in three, CRC the three pieces
// separately and then combine the results.
//
// Combining the results requires precomputed tables, so we must choose a
// fixed buffer length to optimize. The longer the length, the faster; but
// only buffers longer than this length will use the optimization. We choose
// two cutoffs and compute tables for both:
// - one around 512: 168*3=504
// - one around 4KB: 1344*3=4032
//
// -- The nitty gritty --
//
// Let CRC(I, X) be the non-inverted CRC32-C of the sequence X (with
// initial non-inverted CRC I). This function has the following properties:
// (a) CRC(I, AB) = CRC(CRC(I, A), B)
// (b) CRC(I, A xor B) = CRC(I, A) xor CRC(0, B)
//
// Say we want to compute CRC(I, ABC) where A, B, C are three sequences of
// K bytes each, where K is a fixed constant. Let O be the sequence of K zero
// bytes.
//
// CRC(I, ABC) = CRC(I, ABO xor C)
// = CRC(I, ABO) xor CRC(0, C)
// = CRC(CRC(I, AB), O) xor CRC(0, C)
// = CRC(CRC(I, AO xor B), O) xor CRC(0, C)
// = CRC(CRC(I, AO) xor CRC(0, B), O) xor CRC(0, C)
// = CRC(CRC(CRC(I, A), O) xor CRC(0, B), O) xor CRC(0, C)
//
// The castagnoliSSE42Triple function can compute CRC(I, A), CRC(0, B),
// and CRC(0, C) efficiently. We just need to find a way to quickly compute
// CRC(uvwx, O) given a 4-byte initial value uvwx. We can precompute these
// values; since we can't have a 32-bit table, we break it up into four
// 8-bit tables:
//
// CRC(uvwx, O) = CRC(u000, O) xor
// CRC(0v00, O) xor
// CRC(00w0, O) xor
// CRC(000x, O)
//
// We can compute tables corresponding to the four terms for all 8-bit
// values.
crc = ^crc
// If a buffer is long enough to use the optimization, process the first few
// bytes to align the buffer to an 8 byte boundary (if necessary).
if len(p) >= castagnoliK1*3 {
delta := int(uintptr(unsafe.Pointer(&p[0])) & 7)
if delta != 0 {
delta = 8 - delta
crc = castagnoliSSE42(crc, p[:delta])
p = p[delta:]
}
}
// Process 3*K2 at a time.
for len(p) >= castagnoliK2*3 {
// Compute CRC(I, A), CRC(0, B), and CRC(0, C).
crcA, crcB, crcC := castagnoliSSE42Triple(
crc, 0, 0,
p, p[castagnoliK2:], p[castagnoliK2*2:],
castagnoliK2/24)
// CRC(I, AB) = CRC(CRC(I, A), O) xor CRC(0, B)
crcAB := castagnoliShift(castagnoliSSE42TableK2, crcA) ^ crcB
// CRC(I, ABC) = CRC(CRC(I, AB), O) xor CRC(0, C)
crc = castagnoliShift(castagnoliSSE42TableK2, crcAB) ^ crcC
p = p[castagnoliK2*3:]
}
// Process 3*K1 at a time.
for len(p) >= castagnoliK1*3 {
// Compute CRC(I, A), CRC(0, B), and CRC(0, C).
crcA, crcB, crcC := castagnoliSSE42Triple(
crc, 0, 0,
p, p[castagnoliK1:], p[castagnoliK1*2:],
castagnoliK1/24)
// CRC(I, AB) = CRC(CRC(I, A), O) xor CRC(0, B)
crcAB := castagnoliShift(castagnoliSSE42TableK1, crcA) ^ crcB
// CRC(I, ABC) = CRC(CRC(I, AB), O) xor CRC(0, C)
crc = castagnoliShift(castagnoliSSE42TableK1, crcAB) ^ crcC
p = p[castagnoliK1*3:]
}
// Use the simple implementation for what's left.
crc = castagnoliSSE42(crc, p)
return ^crc
}
func archAvailableIEEE() bool {
return useFastIEEE
}
var archIeeeTable8 *slicing8Table
func archInitIEEE() {
if !useFastIEEE {
panic("not available")
}
// We still use slicing-by-8 for small buffers.
archIeeeTable8 = slicingMakeTable(IEEE)
}
func archUpdateIEEE(crc uint32, p []byte) uint32 {
if !useFastIEEE {
panic("not available")
}
if len(p) >= 64 {
left := len(p) & 15
do := len(p) - left
crc = ^ieeeCLMUL(^crc, p[:do])
p = p[do:]
}
if len(p) == 0 {
return crc
}
return slicingUpdate(crc, archIeeeTable8, p)
}
vendor/github.com/klauspost/crc32/crc32_amd64.s
Generated Vendored
+319
View File
@@ -0,0 +1,319 @@
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build gc
#define NOSPLIT 4
#define RODATA 8
// castagnoliSSE42 updates the (non-inverted) crc with the given buffer.
//
// func castagnoliSSE42(crc uint32, p []byte) uint32
TEXT ·castagnoliSSE42(SB), NOSPLIT, $0
MOVL crc+0(FP), AX // CRC value
MOVQ p+8(FP), SI // data pointer
MOVQ p_len+16(FP), CX // len(p)
// If there are fewer than 8 bytes to process, skip alignment.
CMPQ CX, $8
JL less_than_8
MOVQ SI, BX
ANDQ $7, BX
JZ aligned
// Process the first few bytes to 8-byte align the input.
// BX = 8 - BX. We need to process this many bytes to align.
SUBQ $1, BX
XORQ $7, BX
BTQ $0, BX
JNC align_2
CRC32B (SI), AX
DECQ CX
INCQ SI
align_2:
BTQ $1, BX
JNC align_4
// CRC32W (SI), AX
BYTE $0x66; BYTE $0xf2; BYTE $0x0f; BYTE $0x38; BYTE $0xf1; BYTE $0x06
SUBQ $2, CX
ADDQ $2, SI
align_4:
BTQ $2, BX
JNC aligned
// CRC32L (SI), AX
BYTE $0xf2; BYTE $0x0f; BYTE $0x38; BYTE $0xf1; BYTE $0x06
SUBQ $4, CX
ADDQ $4, SI
aligned:
// The input is now 8-byte aligned and we can process 8-byte chunks.
CMPQ CX, $8
JL less_than_8
CRC32Q (SI), AX
ADDQ $8, SI
SUBQ $8, CX
JMP aligned
less_than_8:
// We may have some bytes left over; process 4 bytes, then 2, then 1.
BTQ $2, CX
JNC less_than_4
// CRC32L (SI), AX
BYTE $0xf2; BYTE $0x0f; BYTE $0x38; BYTE $0xf1; BYTE $0x06
ADDQ $4, SI
less_than_4:
BTQ $1, CX
JNC less_than_2
// CRC32W (SI), AX
BYTE $0x66; BYTE $0xf2; BYTE $0x0f; BYTE $0x38; BYTE $0xf1; BYTE $0x06
ADDQ $2, SI
less_than_2:
BTQ $0, CX
JNC done
CRC32B (SI), AX
done:
MOVL AX, ret+32(FP)
RET
// castagnoliSSE42Triple updates three (non-inverted) crcs with (24*rounds)
// bytes from each buffer.
//
// func castagnoliSSE42Triple(
// crc1, crc2, crc3 uint32,
// a, b, c []byte,
// rounds uint32,
// ) (retA uint32, retB uint32, retC uint32)
TEXT ·castagnoliSSE42Triple(SB), NOSPLIT, $0
MOVL crcA+0(FP), AX
MOVL crcB+4(FP), CX
MOVL crcC+8(FP), DX
MOVQ a+16(FP), R8 // data pointer
MOVQ b+40(FP), R9 // data pointer
MOVQ c+64(FP), R10 // data pointer
MOVL rounds+88(FP), R11
loop:
CRC32Q (R8), AX
CRC32Q (R9), CX
CRC32Q (R10), DX
CRC32Q 8(R8), AX
CRC32Q 8(R9), CX
CRC32Q 8(R10), DX
CRC32Q 16(R8), AX
CRC32Q 16(R9), CX
CRC32Q 16(R10), DX
ADDQ $24, R8
ADDQ $24, R9
ADDQ $24, R10
DECQ R11
JNZ loop
MOVL AX, retA+96(FP)
MOVL CX, retB+100(FP)
MOVL DX, retC+104(FP)
RET
// func haveSSE42() bool
TEXT ·haveSSE42(SB), NOSPLIT, $0
XORQ AX, AX
INCL AX
CPUID
SHRQ $20, CX
ANDQ $1, CX
MOVB CX, ret+0(FP)
RET
// func haveCLMUL() bool
TEXT ·haveCLMUL(SB), NOSPLIT, $0
XORQ AX, AX
INCL AX
CPUID
SHRQ $1, CX
ANDQ $1, CX
MOVB CX, ret+0(FP)
RET
// func haveSSE41() bool
TEXT ·haveSSE41(SB), NOSPLIT, $0
XORQ AX, AX
INCL AX
CPUID
SHRQ $19, CX
ANDQ $1, CX
MOVB CX, ret+0(FP)
RET
// CRC32 polynomial data
//
// These constants are lifted from the
// Linux kernel, since they avoid the costly
// PSHUFB 16 byte reversal proposed in the
// original Intel paper.
DATA r2r1kp<>+0(SB)/8, $0x154442bd4
DATA r2r1kp<>+8(SB)/8, $0x1c6e41596
DATA r4r3kp<>+0(SB)/8, $0x1751997d0
DATA r4r3kp<>+8(SB)/8, $0x0ccaa009e
DATA rupolykp<>+0(SB)/8, $0x1db710641
DATA rupolykp<>+8(SB)/8, $0x1f7011641
DATA r5kp<>+0(SB)/8, $0x163cd6124
GLOBL r2r1kp<>(SB), RODATA, $16
GLOBL r4r3kp<>(SB), RODATA, $16
GLOBL rupolykp<>(SB), RODATA, $16
GLOBL r5kp<>(SB), RODATA, $8
// Based on http://www.intel.com/content/dam/www/public/us/en/documents/white-papers/fast-crc-computation-generic-polynomials-pclmulqdq-paper.pdf
// len(p) must be at least 64, and must be a multiple of 16.
// func ieeeCLMUL(crc uint32, p []byte) uint32
TEXT ·ieeeCLMUL(SB), NOSPLIT, $0
MOVL crc+0(FP), X0 // Initial CRC value
MOVQ p+8(FP), SI // data pointer
MOVQ p_len+16(FP), CX // len(p)
MOVOU (SI), X1
MOVOU 16(SI), X2
MOVOU 32(SI), X3
MOVOU 48(SI), X4
PXOR X0, X1
ADDQ $64, SI // buf+=64
SUBQ $64, CX // len-=64
CMPQ CX, $64 // Less than 64 bytes left
JB remain64
MOVOA r2r1kp<>+0(SB), X0
loopback64:
MOVOA X1, X5
MOVOA X2, X6
MOVOA X3, X7
MOVOA X4, X8
PCLMULQDQ $0, X0, X1
PCLMULQDQ $0, X0, X2
PCLMULQDQ $0, X0, X3
PCLMULQDQ $0, X0, X4
// Load next early
MOVOU (SI), X11
MOVOU 16(SI), X12
MOVOU 32(SI), X13
MOVOU 48(SI), X14
PCLMULQDQ $0x11, X0, X5
PCLMULQDQ $0x11, X0, X6
PCLMULQDQ $0x11, X0, X7
PCLMULQDQ $0x11, X0, X8
PXOR X5, X1
PXOR X6, X2
PXOR X7, X3
PXOR X8, X4
PXOR X11, X1
PXOR X12, X2
PXOR X13, X3
PXOR X14, X4
ADDQ $0x40, DI
ADDQ $64, SI // buf+=64
SUBQ $64, CX // len-=64
CMPQ CX, $64 // Less than 64 bytes left?
JGE loopback64
// Fold result into a single register (X1)
remain64:
MOVOA r4r3kp<>+0(SB), X0
MOVOA X1, X5
PCLMULQDQ $0, X0, X1
PCLMULQDQ $0x11, X0, X5
PXOR X5, X1
PXOR X2, X1
MOVOA X1, X5
PCLMULQDQ $0, X0, X1
PCLMULQDQ $0x11, X0, X5
PXOR X5, X1
PXOR X3, X1
MOVOA X1, X5
PCLMULQDQ $0, X0, X1
PCLMULQDQ $0x11, X0, X5
PXOR X5, X1
PXOR X4, X1
// If there is less than 16 bytes left we are done
CMPQ CX, $16
JB finish
// Encode 16 bytes
remain16:
MOVOU (SI), X10
MOVOA X1, X5
PCLMULQDQ $0, X0, X1
PCLMULQDQ $0x11, X0, X5
PXOR X5, X1
PXOR X10, X1
SUBQ $16, CX
ADDQ $16, SI
CMPQ CX, $16
JGE remain16
finish:
// Fold final result into 32 bits and return it
PCMPEQB X3, X3
PCLMULQDQ $1, X1, X0
PSRLDQ $8, X1
PXOR X0, X1
MOVOA X1, X2
MOVQ r5kp<>+0(SB), X0
// Creates 32 bit mask. Note that we don't care about upper half.
PSRLQ $32, X3
PSRLDQ $4, X2
PAND X3, X1
PCLMULQDQ $0, X0, X1
PXOR X2, X1
MOVOA rupolykp<>+0(SB), X0
MOVOA X1, X2
PAND X3, X1
PCLMULQDQ $0x10, X0, X1
PAND X3, X1
PCLMULQDQ $0, X0, X1
PXOR X2, X1
// PEXTRD $1, X1, AX (SSE 4.1)
BYTE $0x66; BYTE $0x0f; BYTE $0x3a
BYTE $0x16; BYTE $0xc8; BYTE $0x01
MOVL AX, ret+32(FP)
RET
vendor/github.com/klauspost/crc32/crc32_amd64p32.go
Generated Vendored
+43
View File
@@ -0,0 +1,43 @@
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !appengine,!gccgo
package crc32
// This file contains the code to call the SSE 4.2 version of the Castagnoli
// CRC.
// haveSSE42 is defined in crc32_amd64p32.s and uses CPUID to test for SSE 4.2
// support.
func haveSSE42() bool
// castagnoliSSE42 is defined in crc32_amd64p32.s and uses the SSE4.2 CRC32
// instruction.
//go:noescape
func castagnoliSSE42(crc uint32, p []byte) uint32
var sse42 = haveSSE42()
func archAvailableCastagnoli() bool {
return sse42
}
func archInitCastagnoli() {
if !sse42 {
panic("not available")
}
// No initialization necessary.
}
func archUpdateCastagnoli(crc uint32, p []byte) uint32 {
if !sse42 {
panic("not available")
}
return castagnoliSSE42(crc, p)
}
func archAvailableIEEE() bool { return false }
func archInitIEEE() { panic("not available") }
func archUpdateIEEE(crc uint32, p []byte) uint32 { panic("not available") }
vendor/github.com/klauspost/crc32/crc32_amd64p32.s
Generated Vendored
+67
View File
@@ -0,0 +1,67 @@
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build gc
#define NOSPLIT 4
#define RODATA 8
// func castagnoliSSE42(crc uint32, p []byte) uint32
TEXT ·castagnoliSSE42(SB), NOSPLIT, $0
MOVL crc+0(FP), AX // CRC value
MOVL p+4(FP), SI // data pointer
MOVL p_len+8(FP), CX // len(p)
NOTL AX
// If there's less than 8 bytes to process, we do it byte-by-byte.
CMPQ CX, $8
JL cleanup
// Process individual bytes until the input is 8-byte aligned.
startup:
MOVQ SI, BX
ANDQ $7, BX
JZ aligned
CRC32B (SI), AX
DECQ CX
INCQ SI
JMP startup
aligned:
// The input is now 8-byte aligned and we can process 8-byte chunks.
CMPQ CX, $8
JL cleanup
CRC32Q (SI), AX
ADDQ $8, SI
SUBQ $8, CX
JMP aligned
cleanup:
// We may have some bytes left over that we process one at a time.
CMPQ CX, $0
JE done
CRC32B (SI), AX
INCQ SI
DECQ CX
JMP cleanup
done:
NOTL AX
MOVL AX, ret+16(FP)
RET
// func haveSSE42() bool
TEXT ·haveSSE42(SB), NOSPLIT, $0
XORQ AX, AX
INCL AX
CPUID
SHRQ $20, CX
ANDQ $1, CX
MOVB CX, ret+0(FP)
RET
vendor/github.com/klauspost/crc32/crc32_generic.go
Generated Vendored
+89
View File
@@ -0,0 +1,89 @@
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// This file contains CRC32 algorithms that are not specific to any architecture
// and don't use hardware acceleration.
//
// The simple (and slow) CRC32 implementation only uses a 256*4 bytes table.
//
// The slicing-by-8 algorithm is a faster implementation that uses a bigger
// table (8*256*4 bytes).
package crc32
// simpleMakeTable allocates and constructs a Table for the specified
// polynomial. The table is suitable for use with the simple algorithm
// (simpleUpdate).
func simpleMakeTable(poly uint32) *Table {
t := new(Table)
simplePopulateTable(poly, t)
return t
}
// simplePopulateTable constructs a Table for the specified polynomial, suitable
// for use with simpleUpdate.
func simplePopulateTable(poly uint32, t *Table) {
for i := 0; i < 256; i++ {
crc := uint32(i)
for j := 0; j < 8; j++ {
if crc&1 == 1 {
crc = (crc >> 1) ^ poly
} else {
crc >>= 1
}
}
t[i] = crc
}
}
// simpleUpdate uses the simple algorithm to update the CRC, given a table that
// was previously computed using simpleMakeTable.
func simpleUpdate(crc uint32, tab *Table, p []byte) uint32 {
crc = ^crc
for _, v := range p {
crc = tab[byte(crc)^v] ^ (crc >> 8)
}
return ^crc
}
// Use slicing-by-8 when payload >= this value.
const slicing8Cutoff = 16
// slicing8Table is array of 8 Tables, used by the slicing-by-8 algorithm.
type slicing8Table [8]Table
// slicingMakeTable constructs a slicing8Table for the specified polynomial. The
// table is suitable for use with the slicing-by-8 algorithm (slicingUpdate).
func slicingMakeTable(poly uint32) *slicing8Table {
t := new(slicing8Table)
simplePopulateTable(poly, &t[0])
for i := 0; i < 256; i++ {
crc := t[0][i]
for j := 1; j < 8; j++ {
crc = t[0][crc&0xFF] ^ (crc >> 8)
t[j][i] = crc
}
}
return t
}
// slicingUpdate uses the slicing-by-8 algorithm to update the CRC, given a
// table that was previously computed using slicingMakeTable.
func slicingUpdate(crc uint32, tab *slicing8Table, p []byte) uint32 {
if len(p) >= slicing8Cutoff {
crc = ^crc
for len(p) > 8 {
crc ^= uint32(p[0]) | uint32(p[1])<<8 | uint32(p[2])<<16 | uint32(p[3])<<24
crc = tab[0][p[7]] ^ tab[1][p[6]] ^ tab[2][p[5]] ^ tab[3][p[4]] ^
tab[4][crc>>24] ^ tab[5][(crc>>16)&0xFF] ^
tab[6][(crc>>8)&0xFF] ^ tab[7][crc&0xFF]
p = p[8:]
}
crc = ^crc
}
if len(p) == 0 {
return crc
}
return simpleUpdate(crc, &tab[0], p)
}
vendor/github.com/klauspost/crc32/crc32_otherarch.go
Generated Vendored
+15
View File
@@ -0,0 +1,15 @@
// Copyright 2011 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !amd64,!amd64p32,!s390x
package crc32
func archAvailableIEEE() bool { return false }
func archInitIEEE() { panic("not available") }
func archUpdateIEEE(crc uint32, p []byte) uint32 { panic("not available") }
func archAvailableCastagnoli() bool { return false }
func archInitCastagnoli() { panic("not available") }
func archUpdateCastagnoli(crc uint32, p []byte) uint32 { panic("not available") }
vendor/github.com/klauspost/crc32/crc32_s390x.go
Generated Vendored
+91
View File
@@ -0,0 +1,91 @@
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build s390x
package crc32
const (
vxMinLen = 64
vxAlignMask = 15 // align to 16 bytes
)
// hasVectorFacility reports whether the machine has the z/Architecture
// vector facility installed and enabled.
func hasVectorFacility() bool
var hasVX = hasVectorFacility()
// vectorizedCastagnoli implements CRC32 using vector instructions.
// It is defined in crc32_s390x.s.
//go:noescape
func vectorizedCastagnoli(crc uint32, p []byte) uint32
// vectorizedIEEE implements CRC32 using vector instructions.
// It is defined in crc32_s390x.s.
//go:noescape
func vectorizedIEEE(crc uint32, p []byte) uint32
func archAvailableCastagnoli() bool {
return hasVX
}
var archCastagnoliTable8 *slicing8Table
func archInitCastagnoli() {
if !hasVX {
panic("not available")
}
// We still use slicing-by-8 for small buffers.
archCastagnoliTable8 = slicingMakeTable(Castagnoli)
}
// archUpdateCastagnoli calculates the checksum of p using
// vectorizedCastagnoli.
func archUpdateCastagnoli(crc uint32, p []byte) uint32 {
if !hasVX {
panic("not available")
}
// Use vectorized function if data length is above threshold.
if len(p) >= vxMinLen {
aligned := len(p) & ^vxAlignMask
crc = vectorizedCastagnoli(crc, p[:aligned])
p = p[aligned:]
}
if len(p) == 0 {
return crc
}
return slicingUpdate(crc, archCastagnoliTable8, p)
}
func archAvailableIEEE() bool {
return hasVX
}
var archIeeeTable8 *slicing8Table
func archInitIEEE() {
if !hasVX {
panic("not available")
}
// We still use slicing-by-8 for small buffers.
archIeeeTable8 = slicingMakeTable(IEEE)
}
// archUpdateIEEE calculates the checksum of p using vectorizedIEEE.
func archUpdateIEEE(crc uint32, p []byte) uint32 {
if !hasVX {
panic("not available")
}
// Use vectorized function if data length is above threshold.
if len(p) >= vxMinLen {
aligned := len(p) & ^vxAlignMask
crc = vectorizedIEEE(crc, p[:aligned])
p = p[aligned:]
}
if len(p) == 0 {
return crc
}
return slicingUpdate(crc, archIeeeTable8, p)
}
vendor/github.com/klauspost/crc32/crc32_s390x.s
Generated Vendored
+249
View File
@@ -0,0 +1,249 @@
// Copyright 2016 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build s390x
#include "textflag.h"
// Vector register range containing CRC-32 constants
#define CONST_PERM_LE2BE V9
#define CONST_R2R1 V10
#define CONST_R4R3 V11
#define CONST_R5 V12
#define CONST_RU_POLY V13
#define CONST_CRC_POLY V14
// The CRC-32 constant block contains reduction constants to fold and
// process particular chunks of the input data stream in parallel.
//
// Note that the constant definitions below are extended in order to compute
// intermediate results with a single VECTOR GALOIS FIELD MULTIPLY instruction.
// The rightmost doubleword can be 0 to prevent contribution to the result or
// can be multiplied by 1 to perform an XOR without the need for a separate
// VECTOR EXCLUSIVE OR instruction.
//
// The polynomials used are bit-reflected:
//
// IEEE: P'(x) = 0x0edb88320
// Castagnoli: P'(x) = 0x082f63b78
// IEEE polynomial constants
DATA ·crcleconskp+0(SB)/8, $0x0F0E0D0C0B0A0908 // LE-to-BE mask
DATA ·crcleconskp+8(SB)/8, $0x0706050403020100
DATA ·crcleconskp+16(SB)/8, $0x00000001c6e41596 // R2
DATA ·crcleconskp+24(SB)/8, $0x0000000154442bd4 // R1
DATA ·crcleconskp+32(SB)/8, $0x00000000ccaa009e // R4
DATA ·crcleconskp+40(SB)/8, $0x00000001751997d0 // R3
DATA ·crcleconskp+48(SB)/8, $0x0000000000000000
DATA ·crcleconskp+56(SB)/8, $0x0000000163cd6124 // R5
DATA ·crcleconskp+64(SB)/8, $0x0000000000000000
DATA ·crcleconskp+72(SB)/8, $0x00000001F7011641 // u'
DATA ·crcleconskp+80(SB)/8, $0x0000000000000000
DATA ·crcleconskp+88(SB)/8, $0x00000001DB710641 // P'(x) << 1
GLOBL ·crcleconskp(SB), RODATA, $144
// Castagonli Polynomial constants
DATA ·crccleconskp+0(SB)/8, $0x0F0E0D0C0B0A0908 // LE-to-BE mask
DATA ·crccleconskp+8(SB)/8, $0x0706050403020100
DATA ·crccleconskp+16(SB)/8, $0x000000009e4addf8 // R2
DATA ·crccleconskp+24(SB)/8, $0x00000000740eef02 // R1
DATA ·crccleconskp+32(SB)/8, $0x000000014cd00bd6 // R4
DATA ·crccleconskp+40(SB)/8, $0x00000000f20c0dfe // R3
DATA ·crccleconskp+48(SB)/8, $0x0000000000000000
DATA ·crccleconskp+56(SB)/8, $0x00000000dd45aab8 // R5
DATA ·crccleconskp+64(SB)/8, $0x0000000000000000
DATA ·crccleconskp+72(SB)/8, $0x00000000dea713f1 // u'
DATA ·crccleconskp+80(SB)/8, $0x0000000000000000
DATA ·crccleconskp+88(SB)/8, $0x0000000105ec76f0 // P'(x) << 1
GLOBL ·crccleconskp(SB), RODATA, $144
// func hasVectorFacility() bool
TEXT ·hasVectorFacility(SB), NOSPLIT, $24-1
MOVD $x-24(SP), R1
XC $24, 0(R1), 0(R1) // clear the storage
MOVD $2, R0 // R0 is the number of double words stored -1
WORD $0xB2B01000 // STFLE 0(R1)
XOR R0, R0 // reset the value of R0
MOVBZ z-8(SP), R1
AND $0x40, R1
BEQ novector
vectorinstalled:
// check if the vector instruction has been enabled
VLEIB $0, $0xF, V16
VLGVB $0, V16, R1
CMPBNE R1, $0xF, novector
MOVB $1, ret+0(FP) // have vx
RET
novector:
MOVB $0, ret+0(FP) // no vx
RET
// The CRC-32 function(s) use these calling conventions:
//
// Parameters:
//
// R2: Initial CRC value, typically ~0; and final CRC (return) value.
// R3: Input buffer pointer, performance might be improved if the
// buffer is on a doubleword boundary.
// R4: Length of the buffer, must be 64 bytes or greater.
//
// Register usage:
//
// R5: CRC-32 constant pool base pointer.
// V0: Initial CRC value and intermediate constants and results.
// V1..V4: Data for CRC computation.
// V5..V8: Next data chunks that are fetched from the input buffer.
//
// V9..V14: CRC-32 constants.
// func vectorizedIEEE(crc uint32, p []byte) uint32
TEXT ·vectorizedIEEE(SB), NOSPLIT, $0
MOVWZ crc+0(FP), R2 // R2 stores the CRC value
MOVD p+8(FP), R3 // data pointer
MOVD p_len+16(FP), R4 // len(p)
MOVD $·crcleconskp(SB), R5
BR vectorizedBody<>(SB)
// func vectorizedCastagnoli(crc uint32, p []byte) uint32
TEXT ·vectorizedCastagnoli(SB), NOSPLIT, $0
MOVWZ crc+0(FP), R2 // R2 stores the CRC value
MOVD p+8(FP), R3 // data pointer
MOVD p_len+16(FP), R4 // len(p)
// R5: crc-32 constant pool base pointer, constant is used to reduce crc
MOVD $·crccleconskp(SB), R5
BR vectorizedBody<>(SB)
TEXT vectorizedBody<>(SB), NOSPLIT, $0
XOR $0xffffffff, R2 // NOTW R2
VLM 0(R5), CONST_PERM_LE2BE, CONST_CRC_POLY
// Load the initial CRC value into the rightmost word of V0
VZERO V0
VLVGF $3, R2, V0
// Crash if the input size is less than 64-bytes.
CMP R4, $64
BLT crash
// Load a 64-byte data chunk and XOR with CRC
VLM 0(R3), V1, V4 // 64-bytes into V1..V4
// Reflect the data if the CRC operation is in the bit-reflected domain
VPERM V1, V1, CONST_PERM_LE2BE, V1
VPERM V2, V2, CONST_PERM_LE2BE, V2
VPERM V3, V3, CONST_PERM_LE2BE, V3
VPERM V4, V4, CONST_PERM_LE2BE, V4
VX V0, V1, V1 // V1 ^= CRC
ADD $64, R3 // BUF = BUF + 64
ADD $(-64), R4
// Check remaining buffer size and jump to proper folding method
CMP R4, $64
BLT less_than_64bytes
fold_64bytes_loop:
// Load the next 64-byte data chunk into V5 to V8
VLM 0(R3), V5, V8
VPERM V5, V5, CONST_PERM_LE2BE, V5
VPERM V6, V6, CONST_PERM_LE2BE, V6
VPERM V7, V7, CONST_PERM_LE2BE, V7
VPERM V8, V8, CONST_PERM_LE2BE, V8
// Perform a GF(2) multiplication of the doublewords in V1 with
// the reduction constants in V0. The intermediate result is
// then folded (accumulated) with the next data chunk in V5 and
// stored in V1. Repeat this step for the register contents
// in V2, V3, and V4 respectively.
VGFMAG CONST_R2R1, V1, V5, V1
VGFMAG CONST_R2R1, V2, V6, V2
VGFMAG CONST_R2R1, V3, V7, V3
VGFMAG CONST_R2R1, V4, V8, V4
// Adjust buffer pointer and length for next loop
ADD $64, R3 // BUF = BUF + 64
ADD $(-64), R4 // LEN = LEN - 64
CMP R4, $64
BGE fold_64bytes_loop
less_than_64bytes:
// Fold V1 to V4 into a single 128-bit value in V1
VGFMAG CONST_R4R3, V1, V2, V1
VGFMAG CONST_R4R3, V1, V3, V1
VGFMAG CONST_R4R3, V1, V4, V1
// Check whether to continue with 64-bit folding
CMP R4, $16
BLT final_fold
fold_16bytes_loop:
VL 0(R3), V2 // Load next data chunk
VPERM V2, V2, CONST_PERM_LE2BE, V2
VGFMAG CONST_R4R3, V1, V2, V1 // Fold next data chunk
// Adjust buffer pointer and size for folding next data chunk
ADD $16, R3
ADD $-16, R4
// Process remaining data chunks
CMP R4, $16
BGE fold_16bytes_loop
final_fold:
VLEIB $7, $0x40, V9
VSRLB V9, CONST_R4R3, V0
VLEIG $0, $1, V0
VGFMG V0, V1, V1
VLEIB $7, $0x20, V9 // Shift by words
VSRLB V9, V1, V2 // Store remaining bits in V2
VUPLLF V1, V1 // Split rightmost doubleword
VGFMAG CONST_R5, V1, V2, V1 // V1 = (V1 * R5) XOR V2
// The input values to the Barret reduction are the degree-63 polynomial
// in V1 (R(x)), degree-32 generator polynomial, and the reduction
// constant u. The Barret reduction result is the CRC value of R(x) mod
// P(x).
//
// The Barret reduction algorithm is defined as:
//
// 1. T1(x) = floor( R(x) / x^32 ) GF2MUL u
// 2. T2(x) = floor( T1(x) / x^32 ) GF2MUL P(x)
// 3. C(x) = R(x) XOR T2(x) mod x^32
//
// Note: To compensate the division by x^32, use the vector unpack
// instruction to move the leftmost word into the leftmost doubleword
// of the vector register. The rightmost doubleword is multiplied
// with zero to not contribute to the intermedate results.
// T1(x) = floor( R(x) / x^32 ) GF2MUL u
VUPLLF V1, V2
VGFMG CONST_RU_POLY, V2, V2
// Compute the GF(2) product of the CRC polynomial in VO with T1(x) in
// V2 and XOR the intermediate result, T2(x), with the value in V1.
// The final result is in the rightmost word of V2.
VUPLLF V2, V2
VGFMAG CONST_CRC_POLY, V2, V1, V2
done:
VLGVF $2, V2, R2
XOR $0xffffffff, R2 // NOTW R2
MOVWZ R2, ret + 32(FP)
RET
crash:
MOVD $0, (R0) // input size is less than 64-bytes