in_tail: fix ignore_active_older_files to re-check mtime on aged-out files

When a file's mtime exceeded ignore_older while being actively monitored,
its inode was registered as aged-out and the file was removed from
monitoring. If new content was later appended (updating mtime), the scan
still excluded the file because the inode comparison matched without
re-checking the mtime.

Re-evaluate mtime in the aged-out inode branch; only skip if the file is
still too old, otherwise unregister the aged-out entry and allow re-pickup.
Applied to both tail_scan_glob.c (Linux/macOS) and tail_scan_win32.c (Windows).

Also preserve file->offset in ignored_file_sizes when aging out a file, so
that on re-pickup the scan resumes from the last-read position rather than
re-reading from the beginning or silently skipping new content by seeking
to EOF.

Signed-off-by: zshuang0316 <zshuang0316@163.com>
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: zshuang0316

plugins/in_tail/tail_file.c

@@ -2438,6 +2438,11 @@ static int check_purge_deleted_file(struct flb_tail_config *ctx,
                                                       file->name,
                                                       strlen(file->name),
                                                       file->inode);
+                /* Preserve read offset for re-pickup if mtime is later refreshed. */
+                flb_tail_scan_register_ignored_file_size(ctx,
+                                                         file->name,
+                                                         strlen(file->name),
+                                                         file->offset);
                 flb_tail_file_remove(file);
                 return FLB_TRUE;
             }

plugins/in_tail/tail_scan_glob.c

@@ -250,10 +250,13 @@ static int tail_scan_path(const char *path, struct flb_tail_config *ctx)
                                                    strlen(globbuf.gl_pathv[i]),
                                                    &aged_out_inode) == 0) {
                 if (aged_out_inode == (uint64_t) st.st_ino) {
-                    flb_plg_debug(ctx->ins,
-                                  "excluded=%s (ignore_active_older_files)",
-                                  globbuf.gl_pathv[i]);
-                    continue;
+                    mtime = flb_tail_stat_mtime(&st);
+                    if (mtime > 0 && (now - ctx->ignore_older) > mtime) {
+                        flb_plg_debug(ctx->ins,
+                                      "excluded=%s (ignore_active_older_files)",
+                                      globbuf.gl_pathv[i]);
+                        continue;
+                    }
                 }
 
                 flb_tail_scan_unregister_aged_out_inode(

plugins/in_tail/tail_scan_win32.c

@@ -109,9 +109,12 @@ static int tail_register_file(const char *target, struct flb_tail_config *ctx,
                                            strlen(path),
                                            &aged_out_inode) == 0) {
         if (aged_out_inode == (uint64_t) st.st_ino) {
-            flb_plg_debug(ctx->ins, "excluded=%s (ignore_active_older_files)",
-                          path);
-            return -1;
+            mtime = flb_tail_stat_mtime(&st);
+            if (mtime > 0 && (ts - ctx->ignore_older) > mtime) {
+                flb_plg_debug(ctx->ins, "excluded=%s (ignore_active_older_files)",
+                              path);
+                return -1;
+            }
         }
 
         flb_tail_scan_unregister_aged_out_inode(ctx, path, strlen(path));