Fix an issue that made it so you could only have a single caller executing

a custom feature at a time.  This was especially problematic when custom
features ran for any appreciable amount of time.

The fix turned out to be quite simple.  The dynamic features are now stored
in a read/write list instead of a list using a mutex.

(closes issue #13478)
Reported by: neutrino88
Fix suggested by file

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@163092 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/res/res_features.c b/res/res_features.c
index 72865f988b8895ee68243061d88c49f9a6585dd0..be9fab630d130961b231e0513007711068f953e4 100644 (file)
--- a/res/res_features.c
+++ b/res/res_features.c
@@ -1008,7 +1008,7 @@ static struct ast_call_feature builtin_features[] =
 };
 
 
-static AST_LIST_HEAD_STATIC(feature_list,ast_call_feature);
+static AST_RWLIST_HEAD_STATIC(feature_list, ast_call_feature);
 
 /*! \brief register new feature into feature_list*/
 void ast_register_feature(struct ast_call_feature *feature)
@@ -1018,12 +1018,13 @@ void ast_register_feature(struct ast_call_feature *feature)
                return;
        }
   
-       AST_LIST_LOCK(&feature_list);
-       AST_LIST_INSERT_HEAD(&feature_list,feature,feature_entry);
-       AST_LIST_UNLOCK(&feature_list);
+       AST_RWLIST_WRLOCK(&feature_list);
+       AST_RWLIST_INSERT_HEAD(&feature_list, feature, feature_entry);
+       AST_RWLIST_UNLOCK(&feature_list);
 
-       if (option_verbose >= 2) 
+       if (option_verbose >= 2) {
                ast_verbose(VERBOSE_PREFIX_2 "Registered Feature '%s'\n",feature->sname);
+       }
 }
 
 /*! \brief unregister feature from feature_list */
@@ -1032,9 +1033,10 @@ void ast_unregister_feature(struct ast_call_feature *feature)
        if (!feature)
                return;
 
-       AST_LIST_LOCK(&feature_list);
-       AST_LIST_REMOVE(&feature_list,feature,feature_entry);
-       AST_LIST_UNLOCK(&feature_list);
+       AST_RWLIST_WRLOCK(&feature_list);
+       AST_RWLIST_REMOVE(&feature_list, feature, feature_entry);
+       AST_RWLIST_UNLOCK(&feature_list);
+       
        free(feature);
 }
 
@@ -1043,10 +1045,11 @@ static void ast_unregister_features(void)
 {
        struct ast_call_feature *feature;
 
-       AST_LIST_LOCK(&feature_list);
-       while ((feature = AST_LIST_REMOVE_HEAD(&feature_list,feature_entry)))
+       AST_RWLIST_WRLOCK(&feature_list);
+       while ((feature = AST_LIST_REMOVE_HEAD(&feature_list, feature_entry))) {
                free(feature);
-       AST_LIST_UNLOCK(&feature_list);
+       }
+       AST_RWLIST_UNLOCK(&feature_list);
 }
 
 /*! \brief find a feature by name */
@@ -1054,9 +1057,10 @@ static struct ast_call_feature *find_dynamic_feature(const char *name)
 {
        struct ast_call_feature *tmp;
 
-       AST_LIST_TRAVERSE(&feature_list, tmp, feature_entry) {
-               if (!strcasecmp(tmp->sname, name))
+       AST_RWLIST_TRAVERSE(&feature_list, tmp, feature_entry) {
+               if (!strcasecmp(tmp->sname, name)) {
                        break;
+               }
        }
 
        return tmp;
@@ -1201,9 +1205,9 @@ static int ast_feature_interpret(struct ast_channel *chan, struct ast_channel *p
        tmp = ast_strdupa(dynamic_features);
 
        while ((tok = strsep(&tmp, "#"))) {
-               AST_LIST_LOCK(&feature_list);   
+               AST_RWLIST_RDLOCK(&feature_list);       
                if (!(feature = find_dynamic_feature(tok))) {
-                       AST_LIST_UNLOCK(&feature_list);
+                       AST_RWLIST_UNLOCK(&feature_list);
                        continue;
                }
                        
@@ -1213,14 +1217,14 @@ static int ast_feature_interpret(struct ast_channel *chan, struct ast_channel *p
                                ast_verbose(VERBOSE_PREFIX_3 " Feature Found: %s exten: %s\n",feature->sname, tok);
                        res = feature->operation(chan, peer, config, code, sense, feature);
                        if (res != FEATURE_RETURN_KEEPTRYING) {
-                               AST_LIST_UNLOCK(&feature_list);
+                               AST_RWLIST_UNLOCK(&feature_list);
                                break;
                        }
                        res = FEATURE_RETURN_PASSDIGITS;
                } else if (!strncmp(feature->exten, code, strlen(code)))
                        res = FEATURE_RETURN_STOREDIGITS;
 
-               AST_LIST_UNLOCK(&feature_list);
+               AST_RWLIST_UNLOCK(&feature_list);
        }
        
        return res;
@@ -1255,14 +1259,14 @@ static void set_config_flags(struct ast_channel *chan, struct ast_channel *peer,
 
                        /* while we have a feature */
                        while ((tok = strsep(&tmp, "#"))) {
-                               AST_LIST_LOCK(&feature_list);
+                               AST_RWLIST_RDLOCK(&feature_list);
                                if ((feature = find_dynamic_feature(tok)) && ast_test_flag(feature, AST_FEATURE_FLAG_NEEDSDTMF)) {
                                        if (ast_test_flag(feature, AST_FEATURE_FLAG_BYCALLER))
                                                ast_set_flag(config, AST_BRIDGE_DTMF_CHANNEL_0);
                                        if (ast_test_flag(feature, AST_FEATURE_FLAG_BYCALLEE))
                                                ast_set_flag(config, AST_BRIDGE_DTMF_CHANNEL_1);
                                }
-                               AST_LIST_UNLOCK(&feature_list);
+                               AST_RWLIST_UNLOCK(&feature_list);
                        }
                }
        }
@@ -2286,13 +2290,14 @@ static int handle_showfeatures(int fd, int argc, char *argv[])
        ast_cli(fd, "\n");
        ast_cli(fd, format, "Dynamic Feature", "Default", "Current");
        ast_cli(fd, format, "---------------", "-------", "-------");
-       if (AST_LIST_EMPTY(&feature_list))
+       if (AST_RWLIST_EMPTY(&feature_list)) {
                ast_cli(fd, "(none)\n");
-       else {
-               AST_LIST_LOCK(&feature_list);
-               AST_LIST_TRAVERSE(&feature_list, feature, feature_entry)
-                       ast_cli(fd, format, feature->sname, "no def", feature->exten);  
-               AST_LIST_UNLOCK(&feature_list);
+       } else {
+               AST_RWLIST_RDLOCK(&feature_list);
+               AST_RWLIST_TRAVERSE(&feature_list, feature, feature_entry) {
+                       ast_cli(fd, format, feature->sname, "no def", feature->exten);
+               }
+               AST_RWLIST_UNLOCK(&feature_list);
        }
        ast_cli(fd, "\nCall parking\n");
        ast_cli(fd, "------------\n");
@@ -2646,13 +2651,13 @@ static int load_config(void)
                        continue;
                }
 
-               AST_LIST_LOCK(&feature_list);
+               AST_RWLIST_RDLOCK(&feature_list);
                if ((feature = find_dynamic_feature(var->name))) {
-                       AST_LIST_UNLOCK(&feature_list);
+                       AST_RWLIST_UNLOCK(&feature_list);
                        ast_log(LOG_WARNING, "Dynamic Feature '%s' specified more than once!\n", var->name);
                        continue;
                }
-               AST_LIST_UNLOCK(&feature_list);
+               AST_RWLIST_UNLOCK(&feature_list);
                                
                if (!(feature = ast_calloc(1, sizeof(*feature))))
                        continue;