channel_internal_api.c: Replace some code with ao2_replace().

Use ao2_replace() instead of ao2_cleanup(); ao2_bump().

ao2_replace() has the advantange of not altering the ref count if the
replaced pointer is the same.

Review: https://reviewboard.asterisk.org/r/3904/
........

Merged revisions 420992 from http://svn.asterisk.org/svn/asterisk/branches/13


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@420993 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/channel.c

@@ -6244,8 +6244,7 @@ static int ast_channel_make_compatible_helper(struct ast_channel *from, struct a
 				ast_format_get_sample_rate(best_src_fmt) : ast_format_get_sample_rate(best_dst_fmt);
 
 			/* pick the best signed linear format based upon what preserves the sample rate the best. */
-			ao2_ref(best_src_fmt, -1);
-			best_src_fmt = ao2_bump(ast_format_cache_get_slin_by_rate(best_sample_rate));
+			ao2_replace(best_src_fmt, ast_format_cache_get_slin_by_rate(best_sample_rate));
 		}
 	}
 

main/channel_internal_api.c

@@ -196,9 +196,9 @@ struct ast_channel {
 	int alertpipe[2];
 	struct ast_format_cap *nativeformats;         /*!< Kinds of data this channel can natively handle */
 	struct ast_format *readformat;            /*!< Requested read format (after translation) */
-	struct ast_format *writeformat;           /*!< Requested write format (after translation) */
+	struct ast_format *writeformat;           /*!< Requested write format (before translation) */
 	struct ast_format *rawreadformat;         /*!< Raw read format (before translation) */
-	struct ast_format *rawwriteformat;        /*!< Raw write format (before translation) */
+	struct ast_format *rawwriteformat;        /*!< Raw write format (after translation) */
 	unsigned int emulate_dtmf_duration;		/*!< Number of ms left to emulate DTMF for */
 #ifdef HAVE_EPOLL
 	int epfd;
@@ -828,8 +828,7 @@ struct ast_format_cap *ast_channel_nativeformats(const struct ast_channel *chan)
 }
 void ast_channel_nativeformats_set(struct ast_channel *chan, struct ast_format_cap *value)
 {
-	ao2_cleanup(chan->nativeformats);
-	chan->nativeformats = ao2_bump(value);
+	ao2_replace(chan->nativeformats, value);
 }
 struct ast_framehook_list *ast_channel_framehooks(const struct ast_channel *chan)
 {
@@ -954,28 +953,23 @@ void ast_channel_state_set(struct ast_channel *chan, enum ast_channel_state valu
 }
 void ast_channel_set_oldwriteformat(struct ast_channel *chan, struct ast_format *format)
 {
-	ao2_cleanup(chan->oldwriteformat);
-	chan->oldwriteformat = ao2_bump(format);
+	ao2_replace(chan->oldwriteformat, format);
 }
 void ast_channel_set_rawreadformat(struct ast_channel *chan, struct ast_format *format)
 {
-	ao2_cleanup(chan->rawreadformat);
-	chan->rawreadformat = ao2_bump(format);
+	ao2_replace(chan->rawreadformat, format);
 }
 void ast_channel_set_rawwriteformat(struct ast_channel *chan, struct ast_format *format)
 {
-	ao2_cleanup(chan->rawwriteformat);
-	chan->rawwriteformat = ao2_bump(format);
+	ao2_replace(chan->rawwriteformat, format);
 }
 void ast_channel_set_readformat(struct ast_channel *chan, struct ast_format *format)
 {
-	ao2_cleanup(chan->readformat);
-	chan->readformat = ao2_bump(format);
+	ao2_replace(chan->readformat, format);
 }
 void ast_channel_set_writeformat(struct ast_channel *chan, struct ast_format *format)
 {
-	ao2_cleanup(chan->writeformat);
-	chan->writeformat = ao2_bump(format);
+	ao2_replace(chan->writeformat, format);
 }
 struct ast_format *ast_channel_oldwriteformat(struct ast_channel *chan)
 {