feat(in_tail): add configurable permission error handling

Author: sandy2008

plugins/in_tail/tail.c

@@ -719,6 +719,14 @@ static struct flb_config_map config_map[] = {
      0, FLB_TRUE, offsetof(struct flb_tail_config, skip_empty_lines),
      "Allows to skip empty lines."
     },
+    {
+     FLB_CONFIG_MAP_BOOL, "skip_permission_errors", "false",
+     0, FLB_TRUE, offsetof(struct flb_tail_config, skip_permission_errors),
+     "Skip directories with permission errors instead of failing. When enabled, "
+     "the plugin will continue processing accessible directories even if some directories "
+     "cannot be read due to permission issues. When disabled (default), any permission error will "
+     "cause the plugin to fail entirely."
+    },
 #ifdef __linux__
     {
      FLB_CONFIG_MAP_BOOL, "file_cache_advise", "true",

plugins/in_tail/tail_config.h

@@ -157,6 +157,9 @@ struct flb_tail_config {
     /* List of shell patterns used to exclude certain file names */
     struct mk_list *exclude_list;
 
+    /* Permission handling configuration */
+    int skip_permission_errors; /* skip directories with permission errors (1), or fail (0) */
+
     /* Plugin input instance */
     struct flb_input_instance *ins;
 

plugins/in_tail/tail_scan_glob.c

@@ -203,13 +203,14 @@ static int tail_scan_path(const char *path, struct flb_tail_config *ctx)
     /* Safe reset for globfree() */
     globbuf.gl_pathv = NULL;
 
-    /* Scan the given path */
+    /* Scan the given path with error checking enabled. */
     ret = do_glob(path, GLOB_TILDE | GLOB_ERR, NULL, &globbuf);
-    if (ret == GLOB_ABORTED) {
+    if (ret == GLOB_ABORTED && ctx->skip_permission_errors) {
         flb_plg_warn(ctx->ins, "read error, check permissions: %s", path);
         globfree(&globbuf);
         ret = do_glob(path, GLOB_TILDE, NULL, &globbuf);
     }
+
     if (ret != 0) {
         switch (ret) {
         case GLOB_NOSPACE: