more efficient (and understandable) ast_channel_walk_locked, and vastly more efficien...
authorKevin P. Fleming <kpfleming@digium.com>
Mon, 6 Jun 2005 02:29:18 +0000 (02:29 +0000)
committerKevin P. Fleming <kpfleming@digium.com>
Mon, 6 Jun 2005 02:29:18 +0000 (02:29 +0000)
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@5853 65c4cc65-6c06-0410-ace0-fbb531ad65f3

14 files changed:
app.c
apps/app_groupcount.c
apps/app_setcdruserfield.c
apps/app_softhangup.c
apps/app_zapscan.c
channel.c
cli.c
include/asterisk/channel.h
manager.c
pbx.c
res/res_agi.c
res/res_features.c
res/res_monitor.c
res/res_musiconhold.c

diff --git a/app.c b/app.c
index b61ff55..9f4267f 100755 (executable)
--- a/app.c
+++ b/app.c
@@ -1013,22 +1013,20 @@ int ast_app_group_get_count(char *group, char *category)
        int count = 0;
        char *test;
        char cat[80] = "";
+       char *s;
 
-       if (category && !ast_strlen_zero(category)) {
-               ast_copy_string(cat, category, sizeof(cat));
-       } else {
-               ast_copy_string(cat, GROUP_CATEGORY_PREFIX, sizeof(cat));
-       }
+       if (group == NULL || ast_strlen_zero(group))
+               return 0;
 
-       if (group && !ast_strlen_zero(group)) {
-               chan = ast_channel_walk_locked(NULL);
-               while(chan) {
-                       test = pbx_builtin_getvar_helper(chan, cat);
-                       if (test && !strcasecmp(test, group))
-                               count++;
-                       ast_mutex_unlock(&chan->lock);
-                       chan = ast_channel_walk_locked(chan);
-               }
+       s = (category && !ast_strlen_zero(category)) ? category : GROUP_CATEGORY_PREFIX;
+       ast_copy_string(cat, s, sizeof(cat));
+
+       chan = NULL;
+       while ((chan = ast_channel_walk_locked(chan)) != NULL) {
+               test = pbx_builtin_getvar_helper(chan, cat);
+               if (test && !strcasecmp(test, group))
+                       count++;
+               ast_mutex_unlock(&chan->lock);
        }
 
        return count;
@@ -1041,6 +1039,7 @@ int ast_app_group_match_get_count(char *groupmatch, char *category)
        int count = 0;
        char *test;
        char cat[80] = "";
+       char *s;
 
        if (!groupmatch || ast_strlen_zero(groupmatch))
                return 0;
@@ -1049,14 +1048,11 @@ int ast_app_group_match_get_count(char *groupmatch, char *category)
        if (regcomp(&regexbuf, groupmatch, REG_EXTENDED | REG_NOSUB))
                return 0;
 
-       if (category && !ast_strlen_zero(category)) {
-               ast_copy_string(cat, category, sizeof(cat));
-       } else {
-               ast_copy_string(cat, GROUP_CATEGORY_PREFIX, sizeof(cat));
-       }
+       s = (category && !ast_strlen_zero(category)) ? category : GROUP_CATEGORY_PREFIX;
+       ast_copy_string(cat, s, sizeof(cat));
 
-       chan = ast_channel_walk_locked(NULL);
-       while(chan) {
+       chan = NULL;
+       while ((chan = ast_channel_walk_locked(chan)) != NULL) {
                test = pbx_builtin_getvar_helper(chan, cat);
                if (test && !regexec(&regexbuf, test, 0, NULL, 0))
                        count++;
index f7ac157..d175210 100755 (executable)
@@ -174,9 +174,8 @@ static int group_show_channels(int fd, int argc, char *argv[])
                havepattern = 1;
        }
 
-       c = ast_channel_walk_locked(NULL);
        ast_cli(fd, FORMAT_STRING, "Channel", "Group", "Category");
-       while(c) {
+       while ( (c = ast_channel_walk_locked(c)) != NULL) {
                headp=&c->varshead;
                AST_LIST_TRAVERSE(headp,current,entries) {
                        if (!strncmp(ast_var_name(current), GROUP_CATEGORY_PREFIX "_", strlen(GROUP_CATEGORY_PREFIX) + 1)) {
@@ -194,7 +193,6 @@ static int group_show_channels(int fd, int argc, char *argv[])
                }
                numchans++;
                ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
        }
 
        if (havepattern)
index 4684fdd..7e820db 100755 (executable)
@@ -76,13 +76,7 @@ static int action_setcdruserfield(struct mansession *s, struct message *m)
                astman_send_error(s, m, "No UserField specified");
                return 0;
        }
-       c = ast_channel_walk_locked(NULL);
-       while (c) {
-               if (!strcasecmp(c->name, channel))
-                       break;
-               ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
-       }
+       c = ast_get_channel_by_name_locked(channel);
        if (!c) {
                astman_send_error(s, m, "No such channel");
                return 0;
index 6631b0a..124f270 100755 (executable)
@@ -60,6 +60,7 @@ static int softhangup_exec(struct ast_channel *chan, void *data)
        while (c) {
                strncpy(name, c->name, sizeof(name)-1);
                ast_mutex_unlock(&c->lock);
+               /* XXX watch out, i think it is wrong to access c-> after unlocking! */
                if (all) {
                        /* CAPI is set up like CAPI[foo/bar]/clcnt */ 
                        if (!strcmp(c->type,"CAPI")) 
index 195fc65..9b153ed 100755 (executable)
@@ -64,15 +64,7 @@ static struct ast_channel *get_zap_channel_locked(int num) {
        char name[80];
        
        snprintf(name,sizeof(name),"Zap/%d-1",num);
-       c = ast_channel_walk_locked(NULL);
-       while(c) {
-               if (!strcasecmp(c->name, name)) {
-                       break;
-               }
-               ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
-       }
-       return c;
+       return ast_get_channel_by_name_locked(name);
 }
 
 static int careful_write(int fd, unsigned char *data, int len)
index d321759..9797f0a 100755 (executable)
--- a/channel.c
+++ b/channel.c
 #define MONITOR_DELAY  150 * 8         /* 150 ms of MONITORING DELAY */
 #endif
 
+/*
+ * Prevent new channel allocation if shutting down.
+ */
 static int shutting_down = 0;
+
 static int uniqueint = 0;
 
 unsigned long global_fin = 0, global_fout = 0;
@@ -71,12 +75,17 @@ unsigned long global_fin = 0, global_fout = 0;
 struct chanlist {
        const struct ast_channel_tech *tech;
        struct chanlist *next;
-} *backends = NULL;
-struct ast_channel *channels = NULL;
+};
 
-/* Protect the channel list (highly unlikely that two things would change
-   it at the same time, but still! */
-   
+static struct chanlist *backends = NULL;
+
+/*
+ * 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);
 
 static int show_channeltypes(int fd, int argc, char *argv[])
@@ -514,72 +523,70 @@ void ast_channel_undefer_dtmf(struct ast_channel *chan)
                ast_clear_flag(chan, AST_FLAG_DEFER_DTMF);
 }
 
-/*--- ast_channel_walk_locked: Browse channels in use */
-struct ast_channel *ast_channel_walk_locked(struct ast_channel *prev)
+/*
+ * Helper function to return the channel after prev, or the one matching name,
+ * with the channel's lock held. If getting the individual lock fails,
+ * unlock and retry quickly up to 10 times, then give up.
+ * 
+ * XXX Note that this code has cost O(N) because of the need to verify
+ * that the object is still on the global list.
+ *
+ * XXX also note that accessing fields (e.g. c->name in ast_log())
+ * can only be done with the lock held or someone could delete the
+ * object while we work on it. This causes some ugliness in the code.
+ * Note that removing the first ast_log() may be harmful, as it would
+ * shorten the retry period and possibly cause failures.
+ * We should definitely go for a better scheme that is deadlock-free.
+ */
+static struct ast_channel *channel_find_locked(const struct ast_channel *prev,
+                                              const char *name)
 {
-       /* Returns next channel (locked) */
-       struct ast_channel *l, *ret;
-       int retries = 0;        
-retry:
-       ret=NULL;
-       ast_mutex_lock(&chlock);
-       l = channels;
-       if (!prev) {
-               if (l) {
-                       if (ast_mutex_trylock(&l->lock)) {
-                               if (retries < 10)
-                                       ast_log(LOG_DEBUG, "Avoiding initial deadlock for '%s'\n", l->name);
-                               else
-                                       ast_log(LOG_WARNING, "Avoided initial deadlock for '%s', %d retries!\n", l->name, retries);
-                               ast_mutex_unlock(&chlock);
-                               if (retries < 10) {
-                                       usleep(1);
-                                       retries++;
-                                       goto retry;
-                               } else
-                                       return NULL;
+       const char *msg = prev ? "initial deadlock" : "deadlock";
+       int retries, done;
+       struct ast_channel *c;
+
+       for (retries = 0; retries < 10; retries++) {
+               ast_mutex_lock(&chlock);
+               for (c = channels; c; c = c->next) {
+                       if (prev == NULL) {
+                               /* want either head of list or match by name */
+                               if (name == NULL || !strcasecmp(name, c->name))
+                                       break;
+                       } else if (c == prev) { /* found, return c->next */
+                               c = c->next;
+                               break;
                        }
                }
+               /* exit if chan not found or mutex acquired successfully */
+               done = (c == NULL) || (ast_mutex_trylock(&c->lock) == 0);
+               /* 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);
-               return l;
-       }
-       while(l) {
-               if (l == prev)
-                       ret = l->next;
-               l = l->next;
-       }
-       if (ret) {
-               if (ast_mutex_trylock(&ret->lock)) {
-                       if (retries < 10)
-                               ast_log(LOG_DEBUG, "Avoiding deadlock for '%s'\n", ret->name);
-                       else
-                               ast_log(LOG_WARNING, "Avoided deadlock for '%s', %d retries!\n", ret->name, retries);
-                       ast_mutex_unlock(&chlock);
-                       if (retries < 10) {
-                               usleep(1);
-                               retries++;
-                               goto retry;
-                       } else
-                               return NULL;
-               }
+               if (done)
+                       return c;
+               usleep(1);
        }
-       ast_mutex_unlock(&chlock);
-       return ret;
-       
+       /*
+        * c is surely not null, but we don't have the lock so cannot
+        * access c->name
+        */
+       ast_log(LOG_WARNING, "Avoided %s for '%p', %d retries!\n",
+               msg, c, retries);
+
+       return NULL;
+}
+
+/*--- ast_channel_walk_locked: Browse channels in use */
+struct ast_channel *ast_channel_walk_locked(const struct ast_channel *prev)
+{
+       return channel_find_locked(prev, NULL);
 }
 
 /*--- ast_get_channel_by_name_locked: Get channel by name and lock it */
-struct ast_channel *ast_get_channel_by_name_locked(char *channame)
+struct ast_channel *ast_get_channel_by_name_locked(const char *name)
 {
-       struct ast_channel *chan;
-       chan = ast_channel_walk_locked(NULL);
-       while(chan) {
-               if (!strcasecmp(chan->name, channame))
-                       return chan;
-               ast_mutex_unlock(&chan->lock);
-               chan = ast_channel_walk_locked(chan);
-       }
-       return NULL;
+       return channel_find_locked(NULL, name);
 }
 
 /*--- ast_safe_sleep_conditional: Wait, look for hangups and condition arg */
diff --git a/cli.c b/cli.c
index b61b589..8e13573 100755 (executable)
--- a/cli.c
+++ b/cli.c
@@ -412,10 +412,9 @@ static int handle_chanlist(int fd, int argc, char *argv[])
                return RESULT_SHOWUSAGE;
        
        concise = (argc == 3 && (!strcasecmp(argv[2],"concise")));
-       c = ast_channel_walk_locked(NULL);
        if(!concise)
                ast_cli(fd, FORMAT_STRING2, "Channel", "Context", "Extension", "Pri", "State", "Appl.", "Data");
-       while(c) {
+       while ( (c = ast_channel_walk_locked(c)) != NULL) {
                if(concise)
                        ast_cli(fd, CONCISE_FORMAT_STRING, c->name, c->context, c->exten, c->priority, ast_state2str(c->_state),
                                        c->appl ? c->appl : "(None)", c->data ? ( !ast_strlen_zero(c->data) ? c->data : "" ): "",
@@ -427,7 +426,6 @@ static int handle_chanlist(int fd, int argc, char *argv[])
 
                numchans++;
                ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
        }
        if(!concise) {
                ast_cli(fd, "%d active channel(s)\n", numchans);
@@ -476,18 +474,12 @@ static int handle_softhangup(int fd, int argc, char *argv[])
        struct ast_channel *c=NULL;
        if (argc != 3)
                return RESULT_SHOWUSAGE;
-       c = ast_channel_walk_locked(NULL);
-       while(c) {
-               if (!strcasecmp(c->name, argv[2])) {
-                       ast_cli(fd, "Requested Hangup on channel '%s'\n", c->name);
-                       ast_softhangup(c, AST_SOFTHANGUP_EXPLICIT);
-                       ast_mutex_unlock(&c->lock);
-                       break;
-               }
+       c = ast_get_channel_by_name_locked(argv[2]);
+       if (c) {
+               ast_cli(fd, "Requested Hangup on channel '%s'\n", c->name);
+               ast_softhangup(c, AST_SOFTHANGUP_EXPLICIT);
                ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
-       }
-       if (!c) 
+       } else
                ast_cli(fd, "%s is not a known channel\n", argv[2]);
        return RESULT_SUCCESS;
 }
@@ -601,6 +593,8 @@ static int handle_debuglevel(int fd, int argc, char *argv[])
        return RESULT_SUCCESS;
 }
 
+#define        DEBUGCHAN_FLAG  0x80000000
+/* XXX todo: merge next two functions!!! */
 static int handle_debugchan(int fd, int argc, char *argv[])
 {
        struct ast_channel *c=NULL;
@@ -610,31 +604,26 @@ static int handle_debugchan(int fd, int argc, char *argv[])
 
        is_all = !strcasecmp("all", argv[2]);
        if (is_all) {
-               global_fin |= 0x80000000;
-               global_fout |= 0x80000000;
+               global_fin |= DEBUGCHAN_FLAG;
+               global_fout |= DEBUGCHAN_FLAG;
+               c = ast_channel_walk_locked(NULL);
+       } else {
+               c = ast_get_channel_by_name_locked(argv[2]);
+               if (c == NULL)
+                       ast_cli(fd, "No such channel %s\n", argv[2]);
        }
-       c = ast_channel_walk_locked(NULL);
        while(c) {
-               if (is_all || !strcasecmp(c->name, argv[2])) {
-                       if (!(c->fin & 0x80000000) || !(c->fout & 0x80000000)) {
-                               c->fin |= 0x80000000;
-                               c->fout |= 0x80000000;
-                               ast_cli(fd, "Debugging enabled on channel %s\n", c->name);
-                       }
-                       if (!is_all)
-                               break;
+               if (!(c->fin & DEBUGCHAN_FLAG) || !(c->fout & DEBUGCHAN_FLAG)) {
+                       c->fin |= DEBUGCHAN_FLAG;
+                       c->fout |= DEBUGCHAN_FLAG;
+                       ast_cli(fd, "Debugging enabled on channel %s\n", c->name);
                }
                ast_mutex_unlock(&c->lock);
+               if (!is_all)
+                       break;
                c = ast_channel_walk_locked(c);
        }
-       if (!is_all) {
-               if (c)
-                       ast_mutex_unlock(&c->lock);
-               else
-                       ast_cli(fd, "No such channel %s\n", argv[2]);
-       }
-       else
-               ast_cli(fd, "Debugging on new channels is enabled\n");
+       ast_cli(fd, "Debugging on new channels is enabled\n");
        return RESULT_SUCCESS;
 }
 
@@ -646,31 +635,26 @@ static int handle_nodebugchan(int fd, int argc, char *argv[])
                return RESULT_SHOWUSAGE;
        is_all = !strcasecmp("all", argv[3]);
        if (is_all) {
-               global_fin &= ~0x80000000;
-               global_fout &= ~0x80000000;
-       }
-       c = ast_channel_walk_locked(NULL);
+               global_fin &= ~DEBUGCHAN_FLAG;
+               global_fout &= ~DEBUGCHAN_FLAG;
+               c = ast_channel_walk_locked(NULL);
+       } else {
+               c = ast_get_channel_by_name_locked(argv[3]);
+               if (c == NULL)
+                       ast_cli(fd, "No such channel %s\n", argv[3]);
+    }
        while(c) {
-               if (is_all || !strcasecmp(c->name, argv[3])) {
-                       if ((c->fin & 0x80000000) || (c->fout & 0x80000000)) {
-                               c->fin &= 0x7fffffff;
-                               c->fout &= 0x7fffffff;
-                               ast_cli(fd, "Debugging disabled on channel %s\n", c->name);
-                       }
-                       if (!is_all)
-                               break;
+               if ((c->fin & DEBUGCHAN_FLAG) || (c->fout & DEBUGCHAN_FLAG)) {
+                       c->fin &= ~DEBUGCHAN_FLAG;
+                       c->fout &= ~DEBUGCHAN_FLAG;
+                       ast_cli(fd, "Debugging disabled on channel %s\n", c->name);
                }
                ast_mutex_unlock(&c->lock);
+               if (!is_all)
+                       break;
                c = ast_channel_walk_locked(c);
        }
-       if (!is_all) {
-               if (c)
-                       ast_mutex_unlock(&c->lock);
-               else
-                       ast_cli(fd, "No such channel %s\n", argv[3]);
-       }
-       else
-               ast_cli(fd, "Debugging on new channels is disabled\n");
+       ast_cli(fd, "Debugging on new channels is disabled\n");
        return RESULT_SUCCESS;
 }
                
@@ -688,94 +672,86 @@ static int handle_showchan(int fd, int argc, char *argv[])
        if (argc != 3)
                return RESULT_SHOWUSAGE;
        gettimeofday(&now, NULL);
-       c = ast_channel_walk_locked(NULL);
-       while(c) {
-               if (!strcasecmp(c->name, argv[2])) {
-                       if(c->cdr) {
-                               elapsed_seconds = now.tv_sec - c->cdr->start.tv_sec;
-                               hour = elapsed_seconds / 3600;
-                               min = (elapsed_seconds % 3600) / 60;
-                               sec = elapsed_seconds % 60;
-                               snprintf(cdrtime, sizeof(cdrtime), "%dh%dm%ds", hour, min, sec);
-                       } else
-                               strncpy(cdrtime, "N/A", sizeof(cdrtime) -1);
-                       ast_cli(fd, 
-                               " -- General --\n"
-                               "           Name: %s\n"
-                               "           Type: %s\n"
-                               "       UniqueID: %s\n"
-                               "      Caller ID: %s\n"
-                               " Caller ID Name: %s\n"
-                               "    DNID Digits: %s\n"
-                               "          State: %s (%d)\n"
-                               "          Rings: %d\n"
-                               "   NativeFormat: %d\n"
-                               "    WriteFormat: %d\n"
-                               "     ReadFormat: %d\n"
-                               "1st File Descriptor: %d\n"
-                               "      Frames in: %d%s\n"
-                               "     Frames out: %d%s\n"
-                               " Time to Hangup: %ld\n"
-                               "   Elapsed Time: %s\n"
-                               "  Direct Bridge: %s\n"
-                               "Indirect Bridge: %s\n"
-                               " --   PBX   --\n"
-                               "        Context: %s\n"
-                               "      Extension: %s\n"
-                               "       Priority: %d\n"
-                               "     Call Group: %d\n"
-                               "   Pickup Group: %d\n"
-                               "    Application: %s\n"
-                               "           Data: %s\n"
-                               "    Blocking in: %s\n",
-                               c->name, c->type, c->uniqueid,
-                               (c->cid.cid_num ? c->cid.cid_num : "(N/A)"),
-                               (c->cid.cid_name ? c->cid.cid_name : "(N/A)"),
-                               (c->cid.cid_dnid ? c->cid.cid_dnid : "(N/A)" ), ast_state2str(c->_state), c->_state, c->rings, c->nativeformats, c->writeformat, c->readformat,
-                               c->fds[0], c->fin & 0x7fffffff, (c->fin & 0x80000000) ? " (DEBUGGED)" : "",
-                               c->fout & 0x7fffffff, (c->fout & 0x80000000) ? " (DEBUGGED)" : "", (long)c->whentohangup,
-                               cdrtime, c->_bridge ? c->_bridge->name : "<none>", ast_bridged_channel(c) ? ast_bridged_channel(c)->name : "<none>", 
-                               c->context, c->exten, c->priority, c->callgroup, c->pickupgroup, ( c->appl ? c->appl : "(N/A)" ),
-                               ( c-> data ? (!ast_strlen_zero(c->data) ? c->data : "(Empty)") : "(None)"),
-                               (ast_test_flag(c, AST_FLAG_BLOCKING) ? c->blockproc : "(Not Blocking)"));
-                       
-                               if(pbx_builtin_serialize_variables(c,buf,sizeof(buf)))
-                                       ast_cli(fd,"      Variables:\n%s\n",buf);
-                               if(c->cdr && ast_cdr_serialize_variables(c->cdr,buf, sizeof(buf), '=', '\n', 1))
-                                       ast_cli(fd,"  CDR Variables:\n%s\n",buf);
-
-                       ast_mutex_unlock(&c->lock);
-                       break;
-               }
-               ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
-       }
-       if (!c) 
+       c = ast_get_channel_by_name_locked(argv[2]);
+       if (!c) {
                ast_cli(fd, "%s is not a known channel\n", argv[2]);
+               return RESULT_SUCCESS;
+       }
+       if(c->cdr) {
+               elapsed_seconds = now.tv_sec - c->cdr->start.tv_sec;
+               hour = elapsed_seconds / 3600;
+               min = (elapsed_seconds % 3600) / 60;
+               sec = elapsed_seconds % 60;
+               snprintf(cdrtime, sizeof(cdrtime), "%dh%dm%ds", hour, min, sec);
+       } else
+               strncpy(cdrtime, "N/A", sizeof(cdrtime) -1);
+       ast_cli(fd, 
+               " -- General --\n"
+               "           Name: %s\n"
+               "           Type: %s\n"
+               "       UniqueID: %s\n"
+               "      Caller ID: %s\n"
+               " Caller ID Name: %s\n"
+               "    DNID Digits: %s\n"
+               "          State: %s (%d)\n"
+               "          Rings: %d\n"
+               "   NativeFormat: %d\n"
+               "    WriteFormat: %d\n"
+               "     ReadFormat: %d\n"
+               "1st File Descriptor: %d\n"
+               "      Frames in: %d%s\n"
+               "     Frames out: %d%s\n"
+               " Time to Hangup: %ld\n"
+               "   Elapsed Time: %s\n"
+               "  Direct Bridge: %s\n"
+               "Indirect Bridge: %s\n"
+               " --   PBX   --\n"
+               "        Context: %s\n"
+               "      Extension: %s\n"
+               "       Priority: %d\n"
+               "     Call Group: %d\n"
+               "   Pickup Group: %d\n"
+               "    Application: %s\n"
+               "           Data: %s\n"
+               "    Blocking in: %s\n",
+               c->name, c->type, c->uniqueid,
+               (c->cid.cid_num ? c->cid.cid_num : "(N/A)"),
+               (c->cid.cid_name ? c->cid.cid_name : "(N/A)"),
+               (c->cid.cid_dnid ? c->cid.cid_dnid : "(N/A)" ), ast_state2str(c->_state), c->_state, c->rings, c->nativeformats, c->writeformat, c->readformat,
+               c->fds[0], c->fin & 0x7fffffff, (c->fin & 0x80000000) ? " (DEBUGGED)" : "",
+               c->fout & 0x7fffffff, (c->fout & 0x80000000) ? " (DEBUGGED)" : "", (long)c->whentohangup,
+               cdrtime, c->_bridge ? c->_bridge->name : "<none>", ast_bridged_channel(c) ? ast_bridged_channel(c)->name : "<none>", 
+               c->context, c->exten, c->priority, c->callgroup, c->pickupgroup, ( c->appl ? c->appl : "(N/A)" ),
+               ( c-> data ? (!ast_strlen_zero(c->data) ? c->data : "(Empty)") : "(None)"),
+               (ast_test_flag(c, AST_FLAG_BLOCKING) ? c->blockproc : "(Not Blocking)"));
+       
+       if(pbx_builtin_serialize_variables(c,buf,sizeof(buf)))
+               ast_cli(fd,"      Variables:\n%s\n",buf);
+       if(c->cdr && ast_cdr_serialize_variables(c->cdr,buf, sizeof(buf), '=', '\n', 1))
+               ast_cli(fd,"  CDR Variables:\n%s\n",buf);
+       
+       ast_mutex_unlock(&c->lock);
        return RESULT_SUCCESS;
 }
 
 static char *complete_ch_helper(char *line, char *word, int pos, int state, int rpos)
 {
-       struct ast_channel *c;
+       struct ast_channel *c = NULL;
        int which=0;
-       char *ret;
+       char *ret = NULL;
+
        if (pos != rpos)
                return NULL;
-       c = ast_channel_walk_locked(NULL);
-       while(c) {
+       while ( (c = ast_channel_walk_locked(c)) != NULL) {
                if (!strncasecmp(word, c->name, strlen(word))) {
-                       if (++which > state)
+                       if (++which > state) {
+                               ret = strdup(c->name);
+                               ast_mutex_unlock(&c->lock);
                                break;
+                       }
                }
                ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
        }
-       if (c) {
-               ret = strdup(c->name);
-               ast_mutex_unlock(&c->lock);
-       } else
-               ret = NULL;
        return ret;
 }
 
index 893e34a..a98442f 100755 (executable)
@@ -744,10 +744,10 @@ int ast_recvchar(struct ast_channel *chan, int timeout);
  * Returns the next channel in the list, NULL on end.
  * If it returns a channel, that channel *has been locked*!
  */
-struct ast_channel *ast_channel_walk_locked(struct ast_channel *prev);
+struct ast_channel *ast_channel_walk_locked(const struct ast_channel *prev);
 
 /*! Get channel by name (locks channel) */
-struct ast_channel *ast_get_channel_by_name_locked(char *channame);
+struct ast_channel *ast_get_channel_by_name_locked(const char *chan);
 
 /*! Waits for a digit */
 /*! 
index 11c671c..5a6af77 100755 (executable)
--- a/manager.c
+++ b/manager.c
@@ -574,14 +574,7 @@ static int action_hangup(struct mansession *s, struct message *m)
                astman_send_error(s, m, "No channel specified");
                return 0;
        }
-       c = ast_channel_walk_locked(NULL);
-       while(c) {
-               if (!strcasecmp(c->name, name)) {
-                       break;
-               }
-               ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
-       }
+       c = ast_get_channel_by_name_locked(name);
        if (!c) {
                astman_send_error(s, m, "No such channel");
                return 0;
@@ -615,14 +608,7 @@ static int action_setvar(struct mansession *s, struct message *m)
                return 0;
        }
 
-       c = ast_channel_walk_locked(NULL);
-       while(c) {
-               if (!strcasecmp(c->name, name)) {
-                       break;
-               }
-               ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
-       }
+       c = ast_get_channel_by_name_locked(name);
        if (!c) {
                astman_send_error(s, m, "No such channel");
                return 0;
@@ -660,14 +646,7 @@ static int action_getvar(struct mansession *s, struct message *m)
                return 0;
        }
 
-       c = ast_channel_walk_locked(NULL);
-       while(c) {
-               if (!strcasecmp(c->name, name)) {
-                       break;
-               }
-               ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
-       }
+       c = ast_get_channel_by_name_locked(name);
        if (!c) {
                astman_send_error(s, m, "No such channel");
                return 0;
@@ -702,25 +681,22 @@ static int action_status(struct mansession *s, struct message *m)
        char bridge[256];
        struct timeval now;
        long elapsed_seconds=0;
+       int all = !name || ast_strlen_zero(name); /* set if we want all channels */
 
        gettimeofday(&now, NULL);
        astman_send_ack(s, m, "Channel status will follow");
-       c = ast_channel_walk_locked(NULL);
         if (id && !ast_strlen_zero(id))
                 snprintf(idText,256,"ActionID: %s\r\n",id);
-       if (name && !ast_strlen_zero(name)) {
-               while (c) {
-                       if (!strcasecmp(c->name, name)) {
-                               break;
-                       }
-                       ast_mutex_unlock(&c->lock);
-                       c = ast_channel_walk_locked(c);
-               }
+       if (all)
+               c = ast_channel_walk_locked(NULL);
+       else {
+               c = ast_get_channel_by_name_locked(name);
                if (!c) {
                        astman_send_error(s, m, "No such channel");
                        return 0;
                }
        }
+       /* if we look by name, we break after the first iteration */
        while(c) {
                if (c->_bridge)
                        snprintf(bridge, sizeof(bridge), "Link: %s\r\n", c->_bridge->name);
@@ -773,10 +749,8 @@ static int action_status(struct mansession *s, struct message *m)
                        ast_state2str(c->_state), bridge, c->uniqueid, idText);
                }
                ast_mutex_unlock(&s->lock);
-               ast_mutex_unlock(&c->lock);
-               if (name && !ast_strlen_zero(name)) {
+               if (!all)
                        break;
-               }
                c = ast_channel_walk_locked(c);
        }
        ast_mutex_lock(&s->lock);
@@ -1175,14 +1149,7 @@ static int action_timeout(struct mansession *s, struct message *m)
                astman_send_error(s, m, "No timeout specified");
                return 0;
        }
-       c = ast_channel_walk_locked(NULL);
-       while(c) {
-               if (!strcasecmp(c->name, name)) {
-                       break;
-               }
-               ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
-       }
+       c = ast_get_channel_by_name_locked(name);
        if (!c) {
                astman_send_error(s, m, "No such channel");
                return 0;
diff --git a/pbx.c b/pbx.c
index 23b000e..1307f67 100755 (executable)
--- a/pbx.c
+++ b/pbx.c
@@ -4453,14 +4453,7 @@ int ast_async_goto_by_name(const char *channame, const char *context, const char
        struct ast_channel *chan;
        int res = -1;
 
-       chan = ast_channel_walk_locked(NULL);
-       while(chan) {
-               if (!strcasecmp(channame, chan->name))
-                       break;
-               ast_mutex_unlock(&chan->lock);
-               chan = ast_channel_walk_locked(chan);
-       }
-       
+       chan = ast_get_channel_by_name_locked(channame);
        if (chan) {
                res = ast_async_goto(chan, context, exten, priority);
                ast_mutex_unlock(&chan->lock);
@@ -5803,7 +5796,7 @@ int pbx_builtin_importvar(struct ast_channel *chan, void *data)
        char *value;
        char *stringp=NULL;
        char *channel;
-       struct ast_channel *chan2=NULL;
+       struct ast_channel *chan2;
        char tmp[4096]="";
        char *s;
 
@@ -5817,11 +5810,7 @@ int pbx_builtin_importvar(struct ast_channel *chan, void *data)
        channel = strsep(&stringp,"|"); 
        value = strsep(&stringp,"\0");
        if (channel && value && name) {
-               while((chan2 = ast_channel_walk_locked(chan2))) {
-                       if (!strcmp(chan2->name, channel))
-                               break;
-                       ast_mutex_unlock(&chan2->lock);
-               }
+               chan2 = ast_get_channel_by_name_locked(channel);
                if (chan2) {
                        s = alloca(strlen(value) + 4);
                        if (s) {
index da28898..f1837b5 100755 (executable)
@@ -960,19 +960,15 @@ static int handle_hangup(struct ast_channel *chan, AGI *agi, int argc, char **ar
                ast_softhangup(chan,AST_SOFTHANGUP_EXPLICIT);
                fdprintf(agi->fd, "200 result=1\n");
                return RESULT_SUCCESS;
-        } else if (argc == 2) {
+       } else if (argc == 2) {
                /* one argument: look for info on the specified channel */
-               c = ast_channel_walk_locked(NULL);
-               while (c) {
-                       if (strcasecmp(argv[1], c->name) == 0) {
-                               /* we have a matching channel */
-                               ast_softhangup(c,AST_SOFTHANGUP_EXPLICIT);
-                               fdprintf(agi->fd, "200 result=1\n");
-                               ast_mutex_unlock(&c->lock);
-                                       return RESULT_SUCCESS;
-                       }
+               c = ast_get_channel_by_name_locked(argv[1]);
+               if (c) {
+                       /* we have a matching channel */
+                       ast_softhangup(c,AST_SOFTHANGUP_EXPLICIT);
+                       fdprintf(agi->fd, "200 result=1\n");
                        ast_mutex_unlock(&c->lock);
-                       c = ast_channel_walk_locked(c);
+                       return RESULT_SUCCESS;
                }
                /* if we get this far no channel name matched the argument given */
                fdprintf(agi->fd, "200 result=-1\n");
@@ -1036,15 +1032,11 @@ static int handle_channelstatus(struct ast_channel *chan, AGI *agi, int argc, ch
                return RESULT_SUCCESS;
        } else if (argc == 3) {
                /* one argument: look for info on the specified channel */
-               c = ast_channel_walk_locked(NULL);
-               while (c) {
-                       if (strcasecmp(argv[2],c->name)==0) {
-                               fdprintf(agi->fd, "200 result=%d\n", c->_state);
-                               ast_mutex_unlock(&c->lock);
-                               return RESULT_SUCCESS;
-                       }
+               c = ast_get_channel_by_name_locked(argv[2]);
+               if (c) {
+                       fdprintf(agi->fd, "200 result=%d\n", c->_state);
                        ast_mutex_unlock(&c->lock);
-                       c = ast_channel_walk_locked(c);
+                       return RESULT_SUCCESS;
                }
                /* if we get this far no channel name matched the argument given */
                fdprintf(agi->fd, "200 result=-1\n");
@@ -1087,15 +1079,11 @@ static int handle_getvariablefull(struct ast_channel *chan, AGI *agi, int argc,
        if ((argc != 4) && (argc != 5))
                return RESULT_SHOWUSAGE;
        if (argc == 5) {
-               while((chan2 = ast_channel_walk_locked(chan2))) {
-                       if (!strcmp(chan2->name, argv[4]))
-                               break;
-                       ast_mutex_unlock(&chan2->lock);
-               }
+               chan2 = ast_get_channel_by_name_locked(argv[4]);
        } else {
                chan2 = chan;
        }
-       if (chan) {
+       if (chan) { /* XXX isn't this chan2 ? */
                pbx_substitute_variables_helper(chan2, argv[3], tmp, sizeof(tmp) - 1);
                fdprintf(agi->fd, "200 result=1 (%s)\n", tmp);
        } else {
index d6363e1..15546c0 100755 (executable)
@@ -1661,10 +1661,9 @@ int load_module(void)
 
 int ast_pickup_call(struct ast_channel *chan)
 {
-       struct ast_channel *cur;
+       struct ast_channel *cur = NULL;
        int res = -1;
-       cur = ast_channel_walk_locked(NULL);
-       while(cur) {
+       while ( (cur = ast_channel_walk_locked(cur)) != NULL) {
                if (!cur->pbx && 
                        (cur != chan) &&
                        (chan->pickupgroup & cur->callgroup) &&
@@ -1673,7 +1672,6 @@ int ast_pickup_call(struct ast_channel *chan)
                                break;
                }
                ast_mutex_unlock(&cur->lock);
-               cur = ast_channel_walk_locked(cur);
        }
        if (cur) {
                if (option_debug)
index cff024d..62d35dd 100755 (executable)
@@ -413,14 +413,7 @@ static int start_monitor_action(struct mansession *s, struct message *m)
                astman_send_error(s, m, "No channel specified");
                return 0;
        }
-       c = ast_channel_walk_locked(NULL);
-       while (c) {
-               if (!strcasecmp(c->name, name)) {
-                       break;
-               }
-               ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
-       }
+       c = ast_get_channel_by_name_locked(name);
        if (!c) {
                astman_send_error(s, m, "No such channel");
                return 0;
@@ -471,14 +464,7 @@ static int stop_monitor_action(struct mansession *s, struct message *m)
                astman_send_error(s, m, "No channel specified");
                return 0;
        }
-       c = ast_channel_walk_locked(NULL);
-       while(c) {
-               if (!strcasecmp(c->name, name)) {
-                       break;
-               }
-               ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
-       }
+       c = ast_get_channel_by_name_locked(name);
        if (!c) {
                astman_send_error(s, m, "No such channel");
                return 0;
@@ -514,14 +500,7 @@ static int change_monitor_action(struct mansession *s, struct message *m)
                astman_send_error(s, m, "No filename specified");
                return 0;
        }
-       c = ast_channel_walk_locked(NULL);
-       while(c) {
-               if (!strcasecmp(c->name, name)) {
-                       break;
-               }
-               ast_mutex_unlock(&c->lock);
-               c = ast_channel_walk_locked(c);
-       }
+       c = ast_get_channel_by_name_locked(name);
        if (!c) {
                astman_send_error(s, m, "No such channel");
                return 0;
index df018b4..3b8c5b0 100755 (executable)
@@ -962,10 +962,11 @@ static void ast_moh_destroy(void)
        ast_mutex_unlock(&moh_lock);
 }
 
-static void moh_on_off(int on) {
-       struct ast_channel *chan = ast_channel_walk_locked(NULL);
+static void moh_on_off(int on)
+{
+       struct ast_channel *chan = NULL;
 
-       while (chan) {
+       while ( (chan = ast_channel_walk_locked(chan)) != NULL) {
                if (ast_test_flag(chan, AST_FLAG_MOH)) {
                        if (on)
                                local_ast_moh_start(chan, NULL);
@@ -973,7 +974,6 @@ static void moh_on_off(int on) {
                                ast_deactivate_generator(chan);
                }
                ast_mutex_unlock(&chan->lock);
-               chan = ast_channel_walk_locked(chan);
        }
 }