0.5.0: Key state files by device id + inode to avoid collisionsHEADmain

1 files changed, 16 insertions, 9 deletions

diff --git a/pylogsentinel/core.py b/pylogsentinel/core.py
index 5ee033e..29ac0e4 100644
--- a/pylogsentinel/core.py
+++ b/pylogsentinel/core.py
@@ -351,11 +351,15 @@ class LockFile:
 
 class StateManager:
     """
-    Manage per-inode state files.
+    Manage per-file state files keyed by device and inode.
 
     Format per file:
         <byte_offset> <line_number>
 
+    The state file is stored at "<state_dir>/<device>/<inode>" to uniquely
+    identify files across different filesystems (which may have overlapping
+    inode numbers).
+
     If file is truncated (size < stored offset) we reset to 0,0.
     """
 
@@ -364,11 +368,11 @@ class StateManager:
     def __init__(self, state_dir: str) -> None:
         self.state_dir = state_dir
 
-    def _path_for_inode(self, inode: int) -> str:
-        return os.path.join(self.state_dir, str(inode))
+    def _path_for_file(self, device: int, inode: int) -> str:
+        return os.path.join(self.state_dir, str(device), str(inode))
 
-    def load(self, inode: int) -> tuple[int, int]:
-        path = self._path_for_inode(inode)
+    def load(self, device: int, inode: int) -> tuple[int, int]:
+        path = self._path_for_file(device, inode)
         try:
             with open(path, "r", encoding="utf-8") as fh:
                 content = fh.read().strip()
@@ -393,11 +397,13 @@ class StateManager:
             return 0, 0
         return byte_offset, line_number
 
-    def save(self, inode: int, byte_offset: int, line_number: int) -> None:
-        path = self._path_for_inode(inode)
+    def save(self, device: int, inode: int, byte_offset: int, line_number: int) -> None:
+        path = self._path_for_file(device, inode)
+        device_dir = os.path.dirname(path)
         tmp_path = f"{path}.tmp"
         data = f"{byte_offset} {line_number}\n"
         try:
+            os.makedirs(device_dir, exist_ok=True)
             with open(tmp_path, "w", encoding="utf-8") as fh:
                 fh.write(data)
             os.replace(tmp_path, path)
@@ -711,8 +717,9 @@ class Sentinel:
             print(f"WARNING: Cannot stat {file_path}: {e}", file=sys.stderr)
             return
 
+        device = st.st_dev
         inode = st.st_ino
-        prev_offset, prev_line_no = self.state_manager.load(inode)
+        prev_offset, prev_line_no = self.state_manager.load(device, inode)
 
         lines, new_offset, new_last_line_no = read_new_lines(
             file_path, prev_offset, prev_line_no, self.max_block_size
@@ -726,7 +733,7 @@ class Sentinel:
             action = self.actions.get(event.rule.action_id) or self.actions["default"]
             execute_action(action, event, skip_actions=self.skip_actions)
 
-        self.state_manager.save(inode, new_offset, new_last_line_no)
+        self.state_manager.save(device, inode, new_offset, new_last_line_no)
 
     def run(self) -> int:
         """