k

MPV/pipeline_helper.py

@@ -1172,6 +1172,11 @@ def _get_ipc_lock_path(ipc_path: str) -> Path:
     return lock_dir / f"medeia-mpv-helper-{safe}.lock"
 
 
+def _get_ipc_lock_meta_path(ipc_path: str) -> Path:
+    lock_path = _get_ipc_lock_path(ipc_path)
+    return lock_path.with_suffix(lock_path.suffix + ".json")
+
+
 def _read_lock_file_pid(ipc_path: str) -> Optional[int]:
     """Return the PID recorded in the lock file by the current holder, or None.
 
@@ -1181,7 +1186,7 @@ def _read_lock_file_pid(ipc_path: str) -> Optional[int]:
     avoiding the race where concurrent sibling helpers all kill each other.
     """
     try:
-        lock_path = _get_ipc_lock_path(ipc_path)
+        lock_path = _get_ipc_lock_meta_path(ipc_path)
         with open(str(lock_path), "r", encoding="utf-8", errors="replace") as fh:
             content = fh.read().strip()
         if not content:
@@ -1193,6 +1198,57 @@ def _read_lock_file_pid(ipc_path: str) -> Optional[int]:
         return None
 
 
+def _write_lock_file_metadata(ipc_path: str) -> None:
+    meta_path = _get_ipc_lock_meta_path(ipc_path)
+    meta_path.write_text(
+        json.dumps(
+            {
+                "pid": os.getpid(),
+                "version": MEDEIA_MPV_HELPER_VERSION,
+                "ipc": str(ipc_path),
+                "started_at": int(time.time()),
+            },
+            ensure_ascii=False,
+        ),
+        encoding="utf-8",
+        errors="replace",
+    )
+
+
+def _release_ipc_lock(fh: Any, ipc_path: Optional[str] = None) -> None:
+    if fh is None:
+        if ipc_path:
+            try:
+                _get_ipc_lock_meta_path(ipc_path).unlink(missing_ok=True)
+            except Exception:
+                pass
+        return
+    try:
+        if os.name == "nt":
+            import msvcrt  # type: ignore
+
+            try:
+                fh.seek(0)
+            except Exception:
+                pass
+            msvcrt.locking(fh.fileno(), msvcrt.LK_UNLCK, 1)
+        else:
+            import fcntl  # type: ignore
+
+            fcntl.flock(fh.fileno(), fcntl.LOCK_UN)
+    except Exception:
+        pass
+    try:
+        fh.close()
+    except Exception:
+        pass
+    if ipc_path:
+        try:
+            _get_ipc_lock_meta_path(ipc_path).unlink(missing_ok=True)
+        except Exception:
+            pass
+
+
 def _acquire_ipc_lock(ipc_path: str) -> Optional[Any]:
     """Best-effort singleton lock per IPC path.
 
@@ -1238,6 +1294,11 @@ def _acquire_ipc_lock(ipc_path: str) -> Optional[Any]:
                     pass
                 return None
 
+        try:
+            _write_lock_file_metadata(ipc_path)
+        except Exception:
+            pass
+
         return fh
     except Exception:
         return None
@@ -1433,20 +1494,7 @@ def main(argv: Optional[list[str]] = None) -> int:
             f"[helper] version={MEDEIA_MPV_HELPER_VERSION} started ipc={args.ipc}"
         )
         try:
-            _lock_fh.seek(0)
-            _lock_fh.truncate()
-            _lock_fh.write(
-                json.dumps(
-                    {
-                        "pid": os.getpid(),
-                        "version": MEDEIA_MPV_HELPER_VERSION,
-                        "ipc": str(args.ipc),
-                        "started_at": int(time.time()),
-                    },
-                    ensure_ascii=False,
-                )
-            )
-            _lock_fh.flush()
+            _write_lock_file_metadata(str(args.ipc))
         except Exception:
             pass
         try:
@@ -2103,6 +2151,10 @@ def main(argv: Optional[list[str]] = None) -> int:
             client.disconnect()
         except Exception:
             pass
+        try:
+            _release_ipc_lock(_lock_fh, str(args.ipc))
+        except Exception:
+            pass
 
     return 0