<p>Richard Mudgett has uploaded this change for <strong>review</strong>.</p><p><a href="https://gerrit.asterisk.org/9217">View Change</a></p><pre style="font-family: monospace,monospace; white-space: pre-wrap;">channel.c: Fix usage of CHECK_BLOCKING()<br><br>The CHECK_BLOCKING() macro is used to indicate if a channel's handling<br>thread is about to do a blocking operation (poll, read, or write) of<br>media.  A few operations such as ast_queue_frame(), soft hangup, and<br>masquerades use the indication to wake up the blocked thread to reevaluate<br>what is going on.<br><br>ASTERISK-27625<br><br>Change-Id: I4dfc33e01e60627d962efa29d0a4244cf151a84d<br>---<br>M include/asterisk/channel.h<br>M main/channel.c<br>2 files changed, 44 insertions(+), 23 deletions(-)<br><br></pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;">git pull ssh://gerrit.asterisk.org:29418/asterisk refs/changes/17/9217/1</pre><pre style="font-family: monospace,monospace; white-space: pre-wrap;">diff --git a/include/asterisk/channel.h b/include/asterisk/channel.h<br>index 16b8a7b..d0c0dbf 100644<br>--- a/include/asterisk/channel.h<br>+++ b/include/asterisk/channel.h<br>@@ -2758,15 +2758,30 @@<br>     return state;<br> }<br> <br>-#define CHECK_BLOCKING(c) do {    \<br>-   if (ast_test_flag(ast_channel_flags(c), AST_FLAG_BLOCKING)) {\<br>-               ast_debug(1, "Thread %p is blocking '%s', already blocked by thread %p in procedure %s\n", \<br>-                       (void *) pthread_self(), ast_channel_name(c), (void *) ast_channel_blocker(c), ast_channel_blockproc(c)); \<br>-  } else { \<br>+/*!<br>+ * \brief Set the blocking indication on the channel.<br>+ *<br>+ * \details<br>+ * Indicate that the thread handling the channel is about to do a blocking<br>+ * operation to wait for media on the channel.  (poll, read, or write)<br>+ *<br>+ * Masquerading and ast_queue_frame() use this indication to wake up the thread.<br>+ *<br>+ * \pre The channel needs to be locked<br>+ */<br>+#define CHECK_BLOCKING(c) \<br>+  do { \<br>+               if (ast_test_flag(ast_channel_flags(c), AST_FLAG_BLOCKING)) { \<br>+                      /* This should not happen as there should only be one thread handling a channel's media at a time. */ \<br>+                  ast_log(LOG_DEBUG, "Thread %p is blocking '%s', already blocked by thread %p in procedure %s\n", \<br>+                         (void *) pthread_self(), ast_channel_name(c), \<br>+                              (void *) ast_channel_blocker(c), ast_channel_blockproc(c)); \<br>+                        ast_assert(0); \<br>+             } \<br>           ast_channel_blocker_set((c), pthread_self()); \<br>               ast_channel_blockproc_set((c), __PRETTY_FUNCTION__); \<br>                ast_set_flag(ast_channel_flags(c), AST_FLAG_BLOCKING); \<br>-     } } while (0)<br>+        } while (0)<br> <br> ast_group_t ast_get_group(const char *s);<br> <br>diff --git a/main/channel.c b/main/channel.c<br>index a29c968..6386de2 100644<br>--- a/main/channel.c<br>+++ b/main/channel.c<br>@@ -5055,11 +5055,9 @@<br>                                /* There is a generator running while we're in the middle of a digit.<br>                              * It's probably inband DTMF, so go ahead and pass it so it can<br>                            * stop the generator */<br>-                             ast_clear_flag(ast_channel_flags(chan), AST_FLAG_BLOCKING);<br>                           ast_channel_unlock(chan);<br>                             res = ast_senddigit_end(chan, fr->subclass.integer, fr->len);<br>                           ast_channel_lock(chan);<br>-                              CHECK_BLOCKING(chan);<br>                         } else if (fr->frametype == AST_FRAME_CONTROL<br>                              && fr->subclass.integer == AST_CONTROL_UNHOLD) {<br>                           /*<br>@@ -5077,7 +5075,6 @@<br>     /* High bit prints debugging */<br>       if (ast_channel_fout(chan) & DEBUGCHAN_FLAG)<br>              ast_frame_dump(ast_channel_name(chan), fr, ">>");<br>-    CHECK_BLOCKING(chan);<br>         switch (fr->frametype) {<br>   case AST_FRAME_CONTROL:<br>               indicate_data_internal(chan, fr->subclass.integer, fr->data.ptr, fr->datalen);<br>@@ -5091,11 +5088,9 @@<br>                               f = fr;<br>               }<br>             send_dtmf_begin_event(chan, DTMF_SENT, fr->subclass.integer);<br>-             ast_clear_flag(ast_channel_flags(chan), AST_FLAG_BLOCKING);<br>           ast_channel_unlock(chan);<br>             res = ast_senddigit_begin(chan, fr->subclass.integer);<br>             ast_channel_lock(chan);<br>-              CHECK_BLOCKING(chan);<br>                 break;<br>        case AST_FRAME_DTMF_END:<br>              if (ast_channel_audiohooks(chan)) {<br>@@ -5107,13 +5102,12 @@<br>                  }<br>             }<br>             send_dtmf_end_event(chan, DTMF_SENT, fr->subclass.integer, fr->len);<br>-           ast_clear_flag(ast_channel_flags(chan), AST_FLAG_BLOCKING);<br>           ast_channel_unlock(chan);<br>             res = ast_senddigit_end(chan, fr->subclass.integer, fr->len);<br>           ast_channel_lock(chan);<br>-              CHECK_BLOCKING(chan);<br>                 break;<br>        case AST_FRAME_TEXT:<br>+         CHECK_BLOCKING(chan);<br>                 if (ast_format_cmp(fr->subclass.format, ast_format_t140) == AST_FORMAT_CMP_EQUAL) {<br>                        res = (ast_channel_tech(chan)->write_text == NULL) ? 0 :<br>                           ast_channel_tech(chan)->write_text(chan, fr);<br>@@ -5121,13 +5115,17 @@<br>                     res = (ast_channel_tech(chan)->send_text == NULL) ? 0 :<br>                            ast_channel_tech(chan)->send_text(chan, (char *) fr->data.ptr);<br>                 }<br>+            ast_clear_flag(ast_channel_flags(chan), AST_FLAG_BLOCKING);<br>           break;<br>        case AST_FRAME_HTML:<br>+         CHECK_BLOCKING(chan);<br>                 res = (ast_channel_tech(chan)->send_html == NULL) ? 0 :<br>                    ast_channel_tech(chan)->send_html(chan, fr->subclass.integer, (char *) fr->data.ptr, fr->datalen);<br>+               ast_clear_flag(ast_channel_flags(chan), AST_FLAG_BLOCKING);<br>           break;<br>        case AST_FRAME_VIDEO:<br>                 /* XXX Handle translation of video codecs one day XXX */<br>+             CHECK_BLOCKING(chan);<br>                 if (ast_channel_tech(chan)->write_stream) {<br>                        if (stream) {<br>                                 res = ast_channel_tech(chan)->write_stream(chan, ast_stream_get_position(stream), fr);<br>@@ -5139,8 +5137,10 @@<br>             } else {<br>                      res = 0;<br>              }<br>+            ast_clear_flag(ast_channel_flags(chan), AST_FLAG_BLOCKING);<br>           break;<br>        case AST_FRAME_MODEM:<br>+                CHECK_BLOCKING(chan);<br>                 if (ast_channel_tech(chan)->write_stream) {<br>                        if (stream) {<br>                                 res = ast_channel_tech(chan)->write_stream(chan, ast_stream_get_position(stream), fr);<br>@@ -5152,6 +5152,7 @@<br>              } else {<br>                      res = 0;<br>              }<br>+            ast_clear_flag(ast_channel_flags(chan), AST_FLAG_BLOCKING);<br>           break;<br>        case AST_FRAME_VOICE:<br>                 if (ast_opt_generic_plc && ast_format_cmp(fr->subclass.format, ast_format_slin) == AST_FORMAT_CMP_EQUAL) {<br>@@ -5201,15 +5202,15 @@<br> <br>                     if (ast_channel_writetrans(chan)) {<br>                           struct ast_frame *trans_frame = ast_translate(ast_channel_writetrans(chan), f, 0);<br>-                               if (trans_frame != f && f != fr) {<br>-                                       /*<br>-                                        * If translate gives us a new frame and so did the audio<br>-                                        * hook then we need to free the one from the audio hook.<br>-                                        */<br>-                                       ast_frfree(f);<br>-                               }<br>-                               f = trans_frame;<br>-                       }<br>+                                if (trans_frame != f && f != fr) {<br>+                                   /*<br>+                                    * If translate gives us a new frame and so did the audio<br>+                                     * hook then we need to free the one from the audio hook.<br>+                                     */<br>+                                  ast_frfree(f);<br>+                               }<br>+                            f = trans_frame;<br>+                     }<br>             }<br> <br>          if (!f) {<br>@@ -5307,6 +5308,7 @@<br>              /* the translator on chan->writetrans may have returned multiple frames<br>               from the single frame we passed in; if so, feed each one of them to the<br>               channel, freeing each one after it has been written */<br>+            CHECK_BLOCKING(chan);<br>                 if ((f != fr) && AST_LIST_NEXT(f, frame_list)) {<br>                      struct ast_frame *cur, *next = NULL;<br>                  unsigned int skip = 0;<br>@@ -5345,6 +5347,7 @@<br>                                 res = 0;<br>                      }<br>             }<br>+            ast_clear_flag(ast_channel_flags(chan), AST_FLAG_BLOCKING);<br>           break;<br>        case AST_FRAME_NULL:<br>  case AST_FRAME_IAX:<br>@@ -5353,23 +5356,26 @@<br>          break;<br>        case AST_FRAME_RTCP:<br>          /* RTCP information is on a per-stream basis and only available on multistream capable channels */<br>+           CHECK_BLOCKING(chan);<br>                 if (ast_channel_tech(chan)->write_stream && stream) {<br>                      res = ast_channel_tech(chan)->write_stream(chan, ast_stream_get_position(stream), fr);<br>             } else {<br>                      res = 0;<br>              }<br>+            ast_clear_flag(ast_channel_flags(chan), AST_FLAG_BLOCKING);<br>           break;<br>        default:<br>              /* At this point, fr is the incoming frame and f is NULL.  Channels do<br>                 * not expect to get NULL as a frame pointer and will segfault.  Hence,<br>                * we output the original frame passed in. */<br>+                CHECK_BLOCKING(chan);<br>                 res = ast_channel_tech(chan)->write(chan, fr);<br>+            ast_clear_flag(ast_channel_flags(chan), AST_FLAG_BLOCKING);<br>           break;<br>        }<br> <br>  if (f && f != fr)<br>             ast_frfree(f);<br>-       ast_clear_flag(ast_channel_flags(chan), AST_FLAG_BLOCKING);<br> <br>        /* Consider a write failure to force a soft hangup */<br>         if (res < 0) {<br></pre><p>To view, visit <a href="https://gerrit.asterisk.org/9217">change 9217</a>. To unsubscribe, visit <a href="https://gerrit.asterisk.org/settings">settings</a>.</p><div itemscope itemtype="http://schema.org/EmailMessage"><div itemscope itemprop="action" itemtype="http://schema.org/ViewAction"><link itemprop="url" href="https://gerrit.asterisk.org/9217"/><meta itemprop="name" content="View Change"/></div></div>

<div style="display:none"> Gerrit-Project: asterisk </div>
<div style="display:none"> Gerrit-Branch: 15 </div>
<div style="display:none"> Gerrit-MessageType: newchange </div>
<div style="display:none"> Gerrit-Change-Id: I4dfc33e01e60627d962efa29d0a4244cf151a84d </div>
<div style="display:none"> Gerrit-Change-Number: 9217 </div>
<div style="display:none"> Gerrit-PatchSet: 1 </div>
<div style="display:none"> Gerrit-Owner: Richard Mudgett <rmudgett@digium.com> </div>