res_musiconhold.c: Use ast_file_read_dir to scan MoH directory

Two changes of note in this patch:

* Use ast_file_read_dir instead of opendir/readdir/closedir

* If the files list should be sorted, do that at the end rather than as
  we go which improves performance for large lists

Change-Id: Ic7e9c913c0f85754c99c74c9cf6dd3514b1b941f

diff --git a/res/res_musiconhold.c b/res/res_musiconhold.c
index dd8dba5573d08e3fb1845921603a1d33b7946a0c..3749d7b98c522fc3b20cbe8fa3c08039d533a736 100644 (file)
--- a/res/res_musiconhold.c
+++ b/res/res_musiconhold.c
@@ -1208,84 +1208,95 @@ static void moh_parse_options(struct ast_variable *var, struct mohclass *mohclas
        }
 }
 
-static int moh_scan_files(struct mohclass *class) {
-
-       DIR *files_DIR;
-       struct dirent *files_dirent;
-       char dir_path[PATH_MAX - sizeof(class->dir)];
-       char filepath[PATH_MAX];
-       char *ext;
-       struct stat statbuf;
-       int res;
-       struct ast_vector_string *files;
+static int on_moh_file(const char *directory, const char *filename, void *obj)
+{
+       struct ast_vector_string *files = obj;
+       char *full_path;
+       char *extension;
 
-       if (class->dir[0] != '/') {
-               snprintf(dir_path, sizeof(dir_path), "%s/%s", ast_config_AST_DATA_DIR, class->dir);
-       } else {
-               ast_copy_string(dir_path, class->dir, sizeof(dir_path));
-       }
-       ast_debug(4, "Scanning '%s' for files for class '%s'\n", dir_path, class->name);
-       files_DIR = opendir(dir_path);
-       if (!files_DIR) {
-               ast_log(LOG_WARNING, "Cannot open dir %s or dir does not exist\n", dir_path);
-               return -1;
+       /* Skip files that starts with a dot */
+       if (*filename == '.') {
+               ast_debug(4, "Skipping '%s/%s' because it starts with a dot\n",
+                       directory, filename);
+               return 0;
        }
 
-       files = moh_file_vector_alloc(16); /* 16 seems like a reasonable default */
-       if (!files) {
-               closedir(files_DIR);
-               return -1;
+       /* We can't do anything with files that don't have an extension,
+        * so check that first and punt if we can't find something */
+       extension = strrchr(filename, '.');
+       if (!extension) {
+               ast_debug(4, "Skipping '%s/%s' because it doesn't have an extension\n",
+                       directory, filename);
+               return 0;
        }
 
-       while ((files_dirent = readdir(files_DIR))) {
-               char *filepath_copy;
+       /* The extension needs at least two characters (after the .) to be useful */
+       if (strlen(extension) < 3) {
+               ast_debug(4, "Skipping '%s/%s' because it doesn't have at least a two "
+                       "character extension\n", directory, filename);
+               return 0;
+       }
 
-               /* The file name must be at least long enough to have the file type extension */
-               if ((strlen(files_dirent->d_name) < 4))
-                       continue;
+       /* Build the full path (excluding the extension) */
+       if (ast_asprintf(&full_path, "%s/%.*s",
+                       directory,
+                       (int) (extension - filename), filename) < 0) {
+               /* If we don't have enough memory to build this path, there is no
+                * point in continuing */
+               return 1;
+       }
 
-               /* Skip files that starts with a dot */
-               if (files_dirent->d_name[0] == '.')
-                       continue;
+       /* If the file is present in multiple formats, ensure we only put it
+        * into the list once. Pretty sure this is O(n^2). */
+       if (AST_VECTOR_GET_CMP(files, &full_path[0], !strcmp)) {
+               ast_free(full_path);
+               return 0;
+       }
 
-               /* Skip files without extensions... they are not audio */
-               if (!strchr(files_dirent->d_name, '.'))
-                       continue;
+       if (AST_VECTOR_APPEND(files, full_path)) {
+               /* AST_VECTOR_APPEND() can only fail on allocation failure, so
+                * we stop iterating */
+               ast_free(full_path);
+               return 1;
+       }
 
-               snprintf(filepath, sizeof(filepath), "%s/%s", dir_path, files_dirent->d_name);
+       return 0;
+}
 
-               if (stat(filepath, &statbuf))
-                       continue;
+static int moh_filename_strcasecmp(const void *a, const void *b)
+{
+       const char **s1 = (const char **) a;
+       const char **s2 = (const char **) b;
+       return strcasecmp(*s1, *s2);
+}
 
-               if (!S_ISREG(statbuf.st_mode))
-                       continue;
+static int moh_scan_files(struct mohclass *class) {
 
-               if ((ext = strrchr(filepath, '.')))
-                       *ext = '\0';
+       char dir_path[PATH_MAX - sizeof(class->dir)];
+       struct ast_vector_string *files;
 
-               /* if the file is present in multiple formats, ensure we only put it into the list once */
-               if (AST_VECTOR_GET_CMP(files, &filepath[0], !strcmp)) {
-                       continue;
-               }
+       if (class->dir[0] != '/') {
+               snprintf(dir_path, sizeof(dir_path), "%s/%s", ast_config_AST_DATA_DIR, class->dir);
+       } else {
+               ast_copy_string(dir_path, class->dir, sizeof(dir_path));
+       }
 
-               filepath_copy = ast_strdup(filepath);
-               if (!filepath_copy) {
-                       break;
-               }
+       ast_debug(4, "Scanning '%s' for files for class '%s'\n", dir_path, class->name);
 
-               if (ast_test_flag(class, MOH_SORTALPHA)) {
-                       res = AST_VECTOR_ADD_SORTED(files, filepath_copy, strcasecmp);
-               } else {
-                       res = AST_VECTOR_APPEND(files, filepath_copy);
-               }
+       /* 16 seems like a reasonable default */
+       files = moh_file_vector_alloc(16);
+       if (!files) {
+               return -1;
+       }
 
-               if (res) {
-                       ast_free(filepath_copy);
-                       break;
-               }
+       if (ast_file_read_dir(dir_path, on_moh_file, files)) {
+               ao2_ref(files, -1);
+               return -1;
        }
 
-       closedir(files_DIR);
+       if (ast_test_flag(class, MOH_SORTALPHA)) {
+               AST_VECTOR_SORT(files, moh_filename_strcasecmp);
+       }
 
        AST_VECTOR_COMPACT(files);