add support for data path option

This commit adds support for configuring the data path via a
configuration file or command-line option. This may be useful
on systems without systemd, such as OpenWrt or Alpine Linux.

Signed-off-by: Maxim Anisimov <maxim.anisimov.ua@gmail.com>

src/config/types.rs

@@ -3,6 +3,7 @@ use ipnetwork::IpNetwork;
 use serde::{Deserialize, Serialize};
 use std::collections::HashMap;
 use std::net::IpAddr;
+use std::path::PathBuf;
 
 use super::defaults::*;
 
@@ -356,6 +357,9 @@ impl Default for NetworkConfig {
 
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct GeneralConfig {
+    #[serde(default)]
+    pub data_path: Option<PathBuf>,
+
     #[serde(default)]
     pub modes: ProxyModes,
 
@@ -871,6 +875,7 @@ pub struct GeneralConfig {
 impl Default for GeneralConfig {
     fn default() -> Self {
         Self {
+            data_path: None,
             modes: ProxyModes::default(),
             prefer_ipv6: false,
             fast_mode: default_true(),

src/maestro/helpers.rs

@@ -1,4 +1,5 @@
 use std::time::Duration;
+use std::path::PathBuf;
 
 use tokio::sync::watch;
 use tracing::{debug, error, info, warn};
@@ -9,8 +10,9 @@ use crate::transport::middle_proxy::{
     ProxyConfigData, fetch_proxy_config_with_raw, load_proxy_config_cache, save_proxy_config_cache,
 };
 
-pub(crate) fn parse_cli() -> (String, bool, Option<String>) {
+pub(crate) fn parse_cli() -> (String, Option<PathBuf>, bool, Option<String>) {
     let mut config_path = "config.toml".to_string();
+    let mut data_path: Option<PathBuf> = None;
     let mut silent = false;
     let mut log_level: Option<String> = None;
 
@@ -28,6 +30,18 @@ pub(crate) fn parse_cli() -> (String, bool, Option<String>) {
     let mut i = 0;
     while i < args.len() {
         match args[i].as_str() {
+            "--data-path" => {
+                i += 1;
+                if i < args.len() {
+                    data_path = Some(PathBuf::from(args[i].clone()));
+                } else {
+                    eprintln!("Missing value for --data-path");
+                    std::process::exit(0);
+                }
+            }
+            s if s.starts_with("--data-path=") => {
+                data_path = Some(PathBuf::from(s.trim_start_matches("--data-path=").to_string()));
+            }
             "--silent" | "-s" => {
                 silent = true;
             }
@@ -44,6 +58,7 @@ pub(crate) fn parse_cli() -> (String, bool, Option<String>) {
                 eprintln!("Usage: telemt [config.toml] [OPTIONS]");
                 eprintln!();
                 eprintln!("Options:");
+                eprintln!("  --data-path <DIR>       Set data directory (absolute path; overrides config value)");
                 eprintln!("  --silent, -s            Suppress info logs");
                 eprintln!("  --log-level <LEVEL>     debug|verbose|normal|silent");
                 eprintln!("  --help, -h              Show this help");
@@ -78,7 +93,7 @@ pub(crate) fn parse_cli() -> (String, bool, Option<String>) {
         i += 1;
     }
 
-    (config_path, silent, log_level)
+    (config_path, data_path, silent, log_level)
 }
 
 pub(crate) fn print_proxy_links(host: &str, port: u16, config: &ProxyConfig) {

src/maestro/mod.rs

@@ -58,7 +58,7 @@ pub async fn run() -> std::result::Result<(), Box<dyn std::error::Error>> {
     startup_tracker
         .start_component(COMPONENT_CONFIG_LOAD, Some("load and validate config".to_string()))
         .await;
-    let (config_path, cli_silent, cli_log_level) = parse_cli();
+    let (config_path, data_path, cli_silent, cli_log_level) = parse_cli();
 
     let mut config = match ProxyConfig::load(&config_path) {
         Ok(c) => c,
@@ -80,6 +80,34 @@ pub async fn run() -> std::result::Result<(), Box<dyn std::error::Error>> {
         std::process::exit(1);
     }
 
+    if let Some(p) = data_path {
+        config.general.data_path = Some(p);
+    }
+
+    if let Some(ref data_path) = config.general.data_path {
+        if !data_path.is_absolute() {
+            eprintln!("[telemt] data_path must be absolute: {}", data_path.display());
+            std::process::exit(1);
+        }
+
+        if data_path.exists() {
+            if !data_path.is_dir() {
+                eprintln!("[telemt] data_path exists but is not a directory: {}", data_path.display());
+                std::process::exit(1);
+            }
+        } else {
+            if let Err(e) = std::fs::create_dir_all(data_path) {
+                eprintln!("[telemt] Can't create data_path {}: {}", data_path.display(), e);
+                std::process::exit(1);
+            }
+        }
+
+        if let Err(e) = std::env::set_current_dir(data_path) {
+            eprintln!("[telemt] Can't use data_path {}: {}", data_path.display(), e);
+            std::process::exit(1);
+        }
+    }
+
     if let Err(e) = crate::network::dns_overrides::install_entries(&config.network.dns_overrides) {
         eprintln!("[telemt] Invalid network.dns_overrides: {}", e);
         std::process::exit(1);