Cache config files, when possible, for speed

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@107928 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/funcs/func_config.c b/funcs/func_config.c
index 2698cac..ecf281c 100644 (file)
--- a/funcs/func_config.c
+++ b/funcs/func_config.c
@@ -34,13 +34,22 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/pbx.h"
 #include "asterisk/app.h"
 
+struct config_item {
+       AST_RWLIST_ENTRY(config_item) entry;
+       struct ast_config *cfg;
+       char filename[0];
+};
+
+static AST_RWLIST_HEAD_STATIC(configs, config_item);
+
 static int config_function_read(struct ast_channel *chan, const char *cmd, char *data, 
        char *buf, size_t len) 
 {
        struct ast_config *cfg;
-       struct ast_flags cfg_flags = { 0 };
+       struct ast_flags cfg_flags = { CONFIG_FLAG_FILEUNCHANGED };
        const char *val;
        char *parse;
+       struct config_item *cur;
        AST_DECLARE_APP_ARGS(args,
                AST_APP_ARG(filename);
                AST_APP_ARG(category);
@@ -75,6 +84,63 @@ static int config_function_read(struct ast_channel *chan, const char *cmd, char
                return -1;
        }
 
+       if (cfg == CONFIG_STATUS_FILEUNCHANGED) {
+               /* Retrieve cfg from list */
+               AST_RWLIST_RDLOCK(&configs);
+               AST_RWLIST_TRAVERSE(&configs, cur, entry) {
+                       if (!strcmp(cur->filename, args.filename)) {
+                               break;
+                       }
+               }
+
+               if (!cur) {
+                       /* At worst, we might leak an entry while upgrading locks */
+                       AST_RWLIST_UNLOCK(&configs);
+                       AST_RWLIST_WRLOCK(&configs);
+                       if (!(cur = ast_malloc(sizeof(*cur) + strlen(args.filename) + 1))) {
+                               AST_RWLIST_UNLOCK(&configs);
+                               return -1;
+                       }
+
+                       strcpy(cur->filename, args.filename);
+
+                       ast_clear_flag(&cfg_flags, CONFIG_FLAG_FILEUNCHANGED);
+                       if (!(cfg = ast_config_load(args.filename, cfg_flags))) {
+                               ast_free(cur);
+                               AST_RWLIST_UNLOCK(&configs);
+                               return -1;
+                       }
+
+                       cur->cfg = cfg;
+                       AST_RWLIST_INSERT_TAIL(&configs, cur, entry);
+               }
+
+               cfg = cur->cfg;
+       } else {
+               /* Replace cfg in list */
+               AST_RWLIST_WRLOCK(&configs);
+               AST_RWLIST_TRAVERSE(&configs, cur, entry) {
+                       if (!strcmp(cur->filename, args.filename)) {
+                               break;
+                       }
+               }
+
+               if (!cur) {
+                       if (!(cur = ast_malloc(sizeof(*cur) + strlen(args.filename) + 1))) {
+                               AST_RWLIST_UNLOCK(&configs);
+                               return -1;
+                       }
+
+                       strcpy(cur->filename, args.filename);
+                       cur->cfg = cfg;
+
+                       AST_RWLIST_INSERT_TAIL(&configs, cur, entry);
+               } else {
+                       ast_config_destroy(cur->cfg);
+                       cur->cfg = cfg;
+               }
+       }
+
        if (!(val = ast_variable_retrieve(cfg, args.category, args.variable))) {
                ast_log(LOG_ERROR, "'%s' not found in [%s] of '%s'\n", args.variable, 
                        args.category, args.filename);
@@ -83,7 +149,8 @@ static int config_function_read(struct ast_channel *chan, const char *cmd, char
 
        ast_copy_string(buf, val, len);
 
-       ast_config_destroy(cfg);
+       /* Unlock down here, so there's no chance the struct goes away while we're using it. */
+       AST_RWLIST_UNLOCK(&configs);
 
        return 0;
 }
@@ -100,7 +167,24 @@ static struct ast_custom_function config_function = {
 
 static int unload_module(void)
 {
-       return ast_custom_function_unregister(&config_function);
+       struct config_item *cur;
+       int res = ast_custom_function_unregister(&config_function);
+
+       /* Allow anything already in the routine to exit */
+       usleep(1);
+       AST_RWLIST_WRLOCK(&configs);
+       usleep(1);
+       AST_RWLIST_UNLOCK(&configs);
+       /* Even if it needed to upgrade a lock */
+       usleep(1);
+       AST_RWLIST_WRLOCK(&configs);
+       /* At this point, no other thread should be queued inside this module */
+       while ((cur = AST_RWLIST_REMOVE_HEAD(&configs, entry))) {
+               ast_config_destroy(cur->cfg);
+               ast_free(cur);
+       }
+       AST_RWLIST_UNLOCK(&configs);
+       return res;
 }
 
 static int load_module(void)