convert ast_channel list to use linked list macros (issue #6338)

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@8571 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channel.c b/channel.c
index 33ae05d4a9d64033f81be7809a76e37de9b5f635..de737f75fa0a708e3b8fdb08aa195a18e94f7161 100644 (file)
--- a/channel.c
+++ b/channel.c
@@ -108,11 +108,9 @@ struct chanlist {
 /*! the list of registered channel types */
 static AST_LIST_HEAD_NOLOCK_STATIC(backends, chanlist);
 
-/*! the list of channels we have */
-static struct ast_channel *channels = NULL;
-
-/*! Protect the channel list, both backends and channels. */
-AST_MUTEX_DEFINE_STATIC(chlock);
+/*! the list of channels we have. Note that the lock for this list is used for
+    both the channels list and the backends list.  */
+static AST_LIST_HEAD_STATIC(channels, ast_channel);
 
 /*! map AST_CAUSE's to readable string representations */
 const struct ast_cause {
@@ -174,7 +172,7 @@ static int show_channeltypes(int fd, int argc, char *argv[])
 
        ast_cli(fd, FORMAT, "Type", "Description",       "Devicestate", "Indications", "Transfer");
        ast_cli(fd, FORMAT, "----------", "-----------", "-----------", "-----------", "--------");
-       if (ast_mutex_lock(&chlock)) {
+       if (AST_LIST_LOCK(&channels)) {
                ast_log(LOG_WARNING, "Unable to lock channel list\n");
                return -1;
        }
@@ -185,7 +183,7 @@ static int show_channeltypes(int fd, int argc, char *argv[])
                        (cl->tech->transfer) ? "yes" : "no");
                count_chan++;
        }
-       ast_mutex_unlock(&chlock);
+       AST_LIST_UNLOCK(&channels);
        ast_cli(fd, "----------\n%d channel drivers registered.\n", count_chan);
        return RESULT_SUCCESS;
 
@@ -200,7 +198,7 @@ static int show_channeltype(int fd, int argc, char *argv[])
        if (argc != 3)
                return RESULT_SHOWUSAGE;
        
-       if (ast_mutex_lock(&chlock)) {
+       if (AST_LIST_LOCK(&channels)) {
                ast_log(LOG_WARNING, "Unable to lock channel list\n");
                return RESULT_FAILURE;
        }
@@ -214,7 +212,7 @@ static int show_channeltype(int fd, int argc, char *argv[])
 
        if (!cl) {
                ast_cli(fd, "\n%s is not a registered channel driver.\n", argv[2]);
-               ast_mutex_unlock(&chlock);
+               AST_LIST_UNLOCK(&channels);
                return RESULT_FAILURE;
        } 
 
@@ -240,7 +238,7 @@ static int show_channeltype(int fd, int argc, char *argv[])
                
        );
 
-       ast_mutex_unlock(&chlock);
+       AST_LIST_UNLOCK(&channels);
        return RESULT_SUCCESS;
 }
 
@@ -317,10 +315,10 @@ void ast_begin_shutdown(int hangup)
        struct ast_channel *c;
        shutting_down = 1;
        if (hangup) {
-               ast_mutex_lock(&chlock);
-               for (c = channels; c; c = c->next)
+               AST_LIST_LOCK(&channels);
+               AST_LIST_TRAVERSE(&channels, c, list)
                        ast_softhangup(c, AST_SOFTHANGUP_SHUTDOWN);
-               ast_mutex_unlock(&chlock);
+               AST_LIST_UNLOCK(&channels);
        }
 }
 
@@ -329,10 +327,10 @@ int ast_active_channels(void)
 {
        struct ast_channel *c;
        int cnt = 0;
-       ast_mutex_lock(&chlock);
-       for (c = channels; c; c = c->next)
+       AST_LIST_LOCK(&channels);
+       AST_LIST_TRAVERSE(&channels, c, list)
                cnt++;
-       ast_mutex_unlock(&chlock);
+       AST_LIST_UNLOCK(&channels);
        return cnt;
 }
 
@@ -393,12 +391,12 @@ int ast_channel_register(const struct ast_channel_tech *tech)
 {
        struct chanlist *chan;
 
-       ast_mutex_lock(&chlock);
+       AST_LIST_LOCK(&channels);
 
        AST_LIST_TRAVERSE(&backends, chan, list) {
                if (!strcasecmp(tech->type, chan->tech->type)) {
                        ast_log(LOG_WARNING, "Already have a handler for type '%s'\n", tech->type);
-                       ast_mutex_unlock(&chlock);
+                       AST_LIST_UNLOCK(&channels);
                        return -1;
                }
        }
@@ -406,7 +404,7 @@ int ast_channel_register(const struct ast_channel_tech *tech)
        chan = malloc(sizeof(*chan));
        if (!chan) {
                ast_log(LOG_WARNING, "Out of memory\n");
-               ast_mutex_unlock(&chlock);
+               AST_LIST_UNLOCK(&channels);
                return -1;
        }
        chan->tech = tech;
@@ -419,7 +417,7 @@ int ast_channel_register(const struct ast_channel_tech *tech)
                ast_verbose(VERBOSE_PREFIX_2 "Registered channel type '%s' (%s)\n", chan->tech->type,
                            chan->tech->description);
 
-       ast_mutex_unlock(&chlock);
+       AST_LIST_UNLOCK(&channels);
        return 0;
 }
 
@@ -430,7 +428,7 @@ void ast_channel_unregister(const struct ast_channel_tech *tech)
        if (option_debug)
                ast_log(LOG_DEBUG, "Unregistering channel type '%s'\n", tech->type);
 
-       ast_mutex_lock(&chlock);
+       AST_LIST_LOCK(&channels);
 
        AST_LIST_TRAVERSE_SAFE_BEGIN(&backends, chan, list) {
                if (chan->tech == tech) {
@@ -443,7 +441,7 @@ void ast_channel_unregister(const struct ast_channel_tech *tech)
        }
        AST_LIST_TRAVERSE_SAFE_END
 
-       ast_mutex_unlock(&chlock);
+       AST_LIST_UNLOCK(&channels);
 }
 
 const struct ast_channel_tech *ast_get_channel_tech(const char *name)
@@ -451,7 +449,7 @@ const struct ast_channel_tech *ast_get_channel_tech(const char *name)
        struct chanlist *chanls;
        const struct ast_channel_tech *ret = NULL;
 
-       if (ast_mutex_lock(&chlock)) {
+       if (AST_LIST_LOCK(&channels)) {
                ast_log(LOG_WARNING, "Unable to lock channel tech list\n");
                return NULL;
        }
@@ -463,7 +461,7 @@ const struct ast_channel_tech *ast_get_channel_tech(const char *name)
                }
        }
 
-       ast_mutex_unlock(&chlock);
+       AST_LIST_UNLOCK(&channels);
        
        return ret;
 }
@@ -664,11 +662,9 @@ struct ast_channel *ast_channel_alloc(int needqueue)
 
        tmp->tech = &null_tech;
 
-       ast_mutex_lock(&chlock);
-       tmp->next = channels;
-       channels = tmp;
-
-       ast_mutex_unlock(&chlock);
+       AST_LIST_LOCK(&channels);
+       AST_LIST_INSERT_HEAD(&channels, tmp, list);
+       AST_LIST_UNLOCK(&channels);
        return tmp;
 }
 
@@ -801,8 +797,8 @@ static struct ast_channel *channel_find_locked(const struct ast_channel *prev,
        struct ast_channel *c;
 
        for (retries = 0; retries < 10; retries++) {
-               ast_mutex_lock(&chlock);
-               for (c = channels; c; c = c->next) {
+               AST_LIST_LOCK(&channels);
+               AST_LIST_TRAVERSE(&channels, c, list) {
                        if (!prev) {
                                /* want head of list */
                                if (!name && !exten)
@@ -831,7 +827,7 @@ static struct ast_channel *channel_find_locked(const struct ast_channel *prev,
                                                break;
                                }
                        } else if (c == prev) { /* found, return c->next */
-                               c = c->next;
+                               c = AST_LIST_NEXT(c, list);
                                break;
                        }
                }
@@ -840,7 +836,7 @@ static struct ast_channel *channel_find_locked(const struct ast_channel *prev,
                /* this is slightly unsafe, as we _should_ hold the lock to access c->name */
                if (!done && c)
                        ast_log(LOG_DEBUG, "Avoiding %s for '%s'\n", msg, c->name);
-               ast_mutex_unlock(&chlock);
+               AST_LIST_UNLOCK(&channels);
                if (done)
                        return c;
                usleep(1);
@@ -929,7 +925,6 @@ static void free_cid(struct ast_callerid *cid)
 /*! \brief Free a channel structure */
 void ast_channel_free(struct ast_channel *chan)
 {
-       struct ast_channel *last=NULL, *cur;
        int fd;
        struct ast_var_t *vardata;
        struct ast_frame *f, *fp;
@@ -938,25 +933,12 @@ void ast_channel_free(struct ast_channel *chan)
        
        headp=&chan->varshead;
        
-       ast_mutex_lock(&chlock);
-       for (cur = channels; cur; cur = cur->next) {
-               if (cur == chan) {
-                       if (last)
-                               last->next = cur->next;
-                       else
-                               channels = cur->next;
-                       break;
-               }
-               last = cur;
-       }
-       if (!cur)
-               ast_log(LOG_WARNING, "Unable to find channel in list\n");
-       else {
-               /* Lock and unlock the channel just to be sure nobody
-                  has it locked still */
-               ast_mutex_lock(&cur->lock);
-               ast_mutex_unlock(&cur->lock);
-       }
+       AST_LIST_LOCK(&channels);
+       AST_LIST_REMOVE(&channels, chan, list);
+       /* Lock and unlock the channel just to be sure nobody
+          has it locked still */
+       ast_mutex_lock(&chan->lock);
+       ast_mutex_unlock(&chan->lock);
        if (chan->tech_pvt) {
                ast_log(LOG_WARNING, "Channel '%s' may not have been hung up properly\n", chan->name);
                free(chan->tech_pvt);
@@ -1007,7 +989,7 @@ void ast_channel_free(struct ast_channel *chan)
                ast_var_delete(vardata);
 
        free(chan);
-       ast_mutex_unlock(&chlock);
+       AST_LIST_UNLOCK(&channels);
 
        ast_device_state_changed_literal(name);
 }
@@ -2564,7 +2546,7 @@ struct ast_channel *ast_request(const char *type, int format, void *data, int *c
                cause = &foo;
        *cause = AST_CAUSE_NOTDEFINED;
 
-       if (ast_mutex_lock(&chlock)) {
+       if (AST_LIST_LOCK(&channels)) {
                ast_log(LOG_WARNING, "Unable to lock channel list\n");
                return NULL;
        }
@@ -2578,10 +2560,10 @@ struct ast_channel *ast_request(const char *type, int format, void *data, int *c
                res = ast_translator_best_choice(&fmt, &capabilities);
                if (res < 0) {
                        ast_log(LOG_WARNING, "No translator path exists for channel type %s (native %d) to %d\n", type, chan->tech->capabilities, format);
-                       ast_mutex_unlock(&chlock);
+                       AST_LIST_UNLOCK(&channels);
                        return NULL;
                }
-               ast_mutex_unlock(&chlock);
+               AST_LIST_UNLOCK(&channels);
                if (!chan->tech->requester)
                        return NULL;
                
@@ -2605,7 +2587,7 @@ struct ast_channel *ast_request(const char *type, int format, void *data, int *c
 
        ast_log(LOG_WARNING, "No channel type registered for '%s'\n", type);
        *cause = AST_CAUSE_NOSUCHDRIVER;
-       ast_mutex_unlock(&chlock);
+       AST_LIST_UNLOCK(&channels);
 
        return NULL;
 }

diff --git a/include/asterisk/channel.h b/include/asterisk/channel.h
index f43b0ef9f2e937385d2efb5a6892564cbabcb8f1..59fbee5fffcde8be9496feb55052428244264895 100644 (file)
--- a/include/asterisk/channel.h
+++ b/include/asterisk/channel.h
@@ -411,7 +411,7 @@ struct ast_channel {
        struct ast_channel_spy_list *spies;
 
        /*! For easy linking */
-       struct ast_channel *next;
+       AST_LIST_ENTRY(ast_channel) list;
 };
 
 /* \defgroup chanprop Channel tech properties: