Fix potential call feature race

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@911 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/channels/chan_zap.c b/channels/chan_zap.c
index 3dc7a83ca7a53d26363e2de0f9abf98e1e953bd8..a3eb6eb116b21d70fed5e66f718927a7d63c6f7a 100755 (executable)
--- a/channels/chan_zap.c
+++ b/channels/chan_zap.c
@@ -2925,6 +2925,9 @@ struct ast_frame *zt_exception(struct ast_channel *ast)
        int res;
        int usedindex=-1;
        int index;
+       struct ast_frame *f;
+
+       ast_pthread_mutex_lock(&p->lock);
 
        index = zt_get_index(ast, p, 1);
        
@@ -3001,15 +3004,21 @@ struct ast_frame *zt_exception(struct ast_channel *ast)
                default:
                        ast_log(LOG_WARNING, "Don't know how to absorb event %s\n", event2str(res));
                }
-               return &p->subs[index].f;
+               f = &p->subs[index].f;
+               ast_pthread_mutex_unlock(&p->lock);
+               return f;
        }
        if (!p->radio) ast_log(LOG_DEBUG, "Exception on %d, channel %d\n", ast->fds[0],p->channel);
        /* If it's not us, return NULL immediately */
        if (ast != p->owner) {
                ast_log(LOG_WARNING, "We're %s, not %s\n", ast->name, p->owner->name);
-               return &p->subs[index].f;
+               f = &p->subs[index].f;
+               ast_pthread_mutex_unlock(&p->lock);
+               return f;
        }
-       return zt_handle_event(ast);
+       f = zt_handle_event(ast);
+       ast_pthread_mutex_unlock(&p->lock);
+       return f;
 }
 
 struct ast_frame  *zt_read(struct ast_channel *ast)
@@ -3133,8 +3142,9 @@ struct ast_frame  *zt_read(struct ast_channel *ast)
        }
        if (res != (p->subs[index].linear ? READ_SIZE * 2 : READ_SIZE)) {
                ast_log(LOG_DEBUG, "Short read (%d/%d), must be an event...\n", res, p->subs[index].linear ? READ_SIZE * 2 : READ_SIZE);
+               f = zt_handle_event(ast);
                pthread_mutex_unlock(&p->lock);
-               return zt_handle_event(ast);
+               return f;
        }
        if (p->tdd) { /* if in TDD mode, see if we receive that */
                int c;