feat: 支持多播放源并发混音

apps/hello/src/stereo_core/alsa.rs

@@ -1,13 +1,13 @@
 #![cfg(target_os = "linux")]
 use anyhow::{Context, Result};
+use std::env;
 use std::fs;
 use std::process::Command;
 
-const FIFO_PATH: &str = "/tmp/stereo_out.fifo";
 const REAL_ASOUND_CONF: &str = "/etc/asound.conf";
 const TEMP_ASOUND_CONF: &str = "/tmp/asound.stereo.conf";
 
-/// ALSA 音频重定向器，用于拦截系统音频输出到 FIFO 管道
+/// ALSA 音频重定向器，通过 Pipe 模式将音频流注入到主进程的混音器中
 pub struct AlsaRedirector;
 
 impl AlsaRedirector {
@@ -17,12 +17,32 @@ impl AlsaRedirector {
         let original_conf = fs::read_to_string(REAL_ASOUND_CONF).unwrap_or_default();
 
         if !original_conf.contains("pcm.original_default") {
+            let current_exe = env::current_exe()
+                .context("无法获取当前可执行文件路径")?
+                .to_string_lossy()
+                .to_string();
+
             // 重命名原有的 default 逻辑，插入拦截器
             let mut new_conf = original_conf.replace("pcm.!default", "pcm.original_default");
             new_conf.push_str(&format!(
-                "\npcm.!default {{ type plug slave {{ pcm \"stereo_interceptor\" format S16_LE rate 48000 channels 2 }} }}\n\
-                pcm.stereo_interceptor {{ type file slave.pcm \"null\" file \"{}\" format \"raw\" }}\n",
-                FIFO_PATH
+                r#"
+pcm.!default {{
+    type plug 
+    slave {{ 
+        pcm "stereo_interceptor" 
+        format S16_LE 
+        rate 48000 
+        channels 2 
+    }}
+}}
+pcm.stereo_interceptor {{
+    type file 
+    slave.pcm "null" 
+    file "| {} --inject" 
+    format "raw"
+}}
+"#,
+                current_exe
             ));
 
             fs::write(TEMP_ASOUND_CONF, new_conf)?;
@@ -40,11 +60,6 @@ impl AlsaRedirector {
             }
         }
 
-        // 创建 FIFO 管道
-        let _ = Command::new("mkfifo").arg(FIFO_PATH).status();
-        let _ = Command::new("chmod").arg("666").arg(FIFO_PATH).status();
-
-        // println!("ALSA 输出已重定向至 {}", FIFO_PATH);
         Ok(Self)
     }
 
@@ -54,12 +69,6 @@ impl AlsaRedirector {
             .arg(format!("umount -l {} >/dev/null 2>&1", REAL_ASOUND_CONF))
             .status();
         let _ = fs::remove_file(TEMP_ASOUND_CONF);
-        let _ = fs::remove_file(FIFO_PATH);
-        // println!("ALSA 配置已恢复。");
-    }
-
-    pub fn fifo_path() -> &'static str {
-        FIFO_PATH
     }
 }