[asterisk-commits] rmudgett: branch 12 r401239 - in /branches/12: apps/ include/asterisk/ main/ ...
SVN commits to the Asterisk project
asterisk-commits at lists.digium.com
Fri Oct 18 11:52:38 CDT 2013
Author: rmudgett
Date: Fri Oct 18 11:52:32 2013
New Revision: 401239
URL: http://svnview.digium.com/svn/asterisk?view=rev&rev=401239
Log:
Add channel lock protection around translation path setup.
Most callers of ast_channel_make_compatible() happen before the channels
enter a two party bridge. With the new bridging framework, two party
bridging technologies may also call ast_channel_make_compatible() when
there is more than one thread involved with the two channels.
* Added channel lock protection in set_format() and
ast_channel_make_compatible_helper() when dealing with the channel's
native formats while setting up a translation path.
* Fixed best_src_fmt and best_dst_fmt usage consistency in
ast_channel_make_compatible_helper(). The call to
ast_translator_best_choice() got them backwards.
* Updated some callers of ast_channel_make_compatible() and the function
documentation. There is actually a difference between the two channels
passed in.
* Fixed the deadlock potential in res_fax.c dealing with
ast_channel_make_compatible(). The deadlock potential was already there
anyway because res_fax called ast_channel_make_compatible() with chan
locked.
(closes issue ASTERISK-22542)
Reported by: Matt Jordan
Review: https://reviewboard.asterisk.org/r/2915/
Modified:
branches/12/apps/app_dial.c
branches/12/include/asterisk/channel.h
branches/12/main/channel.c
branches/12/res/res_fax.c
Modified: branches/12/apps/app_dial.c
URL: http://svnview.digium.com/svn/asterisk/branches/12/apps/app_dial.c?view=diff&rev=401239&r1=401238&r2=401239
==============================================================================
--- branches/12/apps/app_dial.c (original)
+++ branches/12/apps/app_dial.c Fri Oct 18 11:52:32 2013
@@ -870,7 +870,7 @@
c = o->chan = ast_request(tech, ast_channel_nativeformats(in), in, stuff, &cause);
if (c) {
if (single && !caller_entertained) {
- ast_channel_make_compatible(o->chan, in);
+ ast_channel_make_compatible(in, o->chan);
}
ast_channel_lock_both(in, o->chan);
ast_channel_inherit_variables(in, o->chan);
@@ -1070,7 +1070,7 @@
ast_deactivate_generator(in);
/* If we are calling a single channel, and not providing ringback or music, */
/* then, make them compatible for in-band tone purpose */
- if (ast_channel_make_compatible(outgoing->chan, in) < 0) {
+ if (ast_channel_make_compatible(in, outgoing->chan) < 0) {
/* If these channels can not be made compatible,
* there is no point in continuing. The bridge
* will just fail if it gets that far.
Modified: branches/12/include/asterisk/channel.h
URL: http://svnview.digium.com/svn/asterisk/branches/12/include/asterisk/channel.h?view=diff&rev=401239&r1=401238&r2=401239
==============================================================================
--- branches/12/include/asterisk/channel.h (original)
+++ branches/12/include/asterisk/channel.h Fri Oct 18 11:52:32 2013
@@ -1984,14 +1984,23 @@
/*!
- * \brief Makes two channel formats compatible
- * \param c0 first channel to make compatible
- * \param c1 other channel to make compatible
- * \details
- * Set two channels to compatible formats -- call before ast_channel_bridge in general.
- * \return Returns 0 on success and -1 if it could not be done
- */
-int ast_channel_make_compatible(struct ast_channel *c0, struct ast_channel *c1);
+ * \brief Make the frame formats of two channels compatible.
+ *
+ * \param chan First channel to make compatible. Should be the calling party.
+ * \param peer Other channel to make compatible. Should be the called party.
+ *
+ * \note Absolutely _NO_ channel locks should be held before calling this function.
+ *
+ * \details
+ * Set two channels to compatible frame formats in both
+ * directions. The path from peer to chan is made compatible
+ * first to allow for in-band audio in case the other direction
+ * cannot be made compatible.
+ *
+ * \retval 0 on success.
+ * \retval -1 on error.
+ */
+int ast_channel_make_compatible(struct ast_channel *chan, struct ast_channel *peer);
/*!
* \brief Bridge two channels together (early)
Modified: branches/12/main/channel.c
URL: http://svnview.digium.com/svn/asterisk/branches/12/main/channel.c?view=diff&rev=401239&r1=401238&r2=401239
==============================================================================
--- branches/12/main/channel.c (original)
+++ branches/12/main/channel.c Fri Oct 18 11:52:32 2013
@@ -5288,11 +5288,10 @@
const int direction)
{
struct ast_trans_pvt *trans_pvt;
- struct ast_format_cap *cap_native = ast_channel_nativeformats(chan);
+ struct ast_format_cap *cap_native;
struct ast_format best_set_fmt;
struct ast_format best_native_fmt;
int res;
- char from[200], to[200];
ast_best_codec(cap_set, &best_set_fmt);
@@ -5323,6 +5322,9 @@
return 0;
}
+
+ ast_channel_lock(chan);
+ cap_native = ast_channel_nativeformats(chan);
/* Find a translation path from the native format to one of the desired formats */
if (!direction) {
@@ -5332,17 +5334,20 @@
/* writing */
res = ast_translator_best_choice(cap_native, cap_set, &best_native_fmt, &best_set_fmt);
}
-
if (res < 0) {
+ char from[200];
+ char to[200];
+
+ ast_getformatname_multiple(from, sizeof(from), cap_native);
+ ast_channel_unlock(chan);
+ ast_getformatname_multiple(to, sizeof(to), cap_set);
+
ast_log(LOG_WARNING, "Unable to find a codec translation path from %s to %s\n",
- ast_getformatname_multiple(from, sizeof(from), cap_native),
- ast_getformatname_multiple(to, sizeof(to), cap_set));
+ from, to);
return -1;
}
/* Now we have a good choice for both. */
- ast_channel_lock(chan);
-
if ((ast_format_cmp(rawformat, &best_native_fmt) != AST_FORMAT_CMP_NOT_EQUAL) &&
(ast_format_cmp(format, &best_set_fmt) != AST_FORMAT_CMP_NOT_EQUAL) &&
((ast_format_cmp(rawformat, format) != AST_FORMAT_CMP_NOT_EQUAL) || trans->get(chan))) {
@@ -6144,24 +6149,41 @@
/*! \brief Set up translation from one channel to another */
static int ast_channel_make_compatible_helper(struct ast_channel *from, struct ast_channel *to)
{
- struct ast_format_cap *src_cap = ast_channel_nativeformats(from); /* shallow copy, do not destroy */
- struct ast_format_cap *dst_cap = ast_channel_nativeformats(to); /* shallow copy, do not destroy */
+ struct ast_format_cap *src_cap;
+ struct ast_format_cap *dst_cap;
struct ast_format best_src_fmt;
struct ast_format best_dst_fmt;
- int use_slin;
+ int no_path;
+
+ ast_channel_lock_both(from, to);
if ((ast_format_cmp(ast_channel_readformat(from), ast_channel_writeformat(to)) != AST_FORMAT_CMP_NOT_EQUAL) &&
(ast_format_cmp(ast_channel_readformat(to), ast_channel_writeformat(from)) != AST_FORMAT_CMP_NOT_EQUAL)) {
/* Already compatible! Moving on ... */
+ ast_channel_unlock(to);
+ ast_channel_unlock(from);
return 0;
}
+ src_cap = ast_channel_nativeformats(from); /* shallow copy, do not destroy */
+ dst_cap = ast_channel_nativeformats(to); /* shallow copy, do not destroy */
+
/* If there's no audio in this call, don't bother with trying to find a translation path */
- if (!ast_format_cap_has_type(src_cap, AST_FORMAT_TYPE_AUDIO) || !ast_format_cap_has_type(dst_cap, AST_FORMAT_TYPE_AUDIO))
+ if (!ast_format_cap_has_type(src_cap, AST_FORMAT_TYPE_AUDIO)
+ || !ast_format_cap_has_type(dst_cap, AST_FORMAT_TYPE_AUDIO)) {
+ ast_channel_unlock(to);
+ ast_channel_unlock(from);
return 0;
-
- if (ast_translator_best_choice(dst_cap, src_cap, &best_src_fmt, &best_dst_fmt) < 0) {
- ast_log(LOG_WARNING, "No path to translate from %s to %s\n", ast_channel_name(from), ast_channel_name(to));
+ }
+
+ no_path = ast_translator_best_choice(dst_cap, src_cap, &best_dst_fmt, &best_src_fmt);
+
+ ast_channel_unlock(to);
+ ast_channel_unlock(from);
+
+ if (no_path) {
+ ast_log(LOG_WARNING, "No path to translate from %s to %s\n",
+ ast_channel_name(from), ast_channel_name(to));
return -1;
}
@@ -6171,24 +6193,28 @@
* no direct conversion available. If generic PLC is
* desired, then transcoding via SLINEAR is a requirement
*/
- use_slin = ast_format_is_slinear(&best_src_fmt) || ast_format_is_slinear(&best_dst_fmt) ? 1 : 0;
- if ((ast_format_cmp(&best_src_fmt, &best_dst_fmt) == AST_FORMAT_CMP_NOT_EQUAL) &&
- (ast_opt_generic_plc || ast_opt_transcode_via_slin) &&
- (ast_translate_path_steps(&best_dst_fmt, &best_src_fmt) != 1 || use_slin)) {
-
- int best_sample_rate = ast_format_rate(&best_src_fmt) > ast_format_rate(&best_dst_fmt) ?
- ast_format_rate(&best_src_fmt) : ast_format_rate(&best_dst_fmt);
-
- /* pick the best signed linear format based upon what preserves the sample rate the best. */
- ast_format_set(&best_dst_fmt, ast_format_slin_by_rate(best_sample_rate), 0);
- }
-
- if (ast_set_read_format(from, &best_dst_fmt) < 0) {
- ast_log(LOG_WARNING, "Unable to set read format on channel %s to %s\n", ast_channel_name(from), ast_getformatname(&best_dst_fmt));
+ if (ast_format_cmp(&best_dst_fmt, &best_src_fmt) == AST_FORMAT_CMP_NOT_EQUAL
+ && (ast_opt_generic_plc || ast_opt_transcode_via_slin)) {
+ int use_slin = (ast_format_is_slinear(&best_src_fmt)
+ || ast_format_is_slinear(&best_dst_fmt)) ? 1 : 0;
+
+ if (use_slin || ast_translate_path_steps(&best_dst_fmt, &best_src_fmt) != 1) {
+ int best_sample_rate = (ast_format_rate(&best_src_fmt) > ast_format_rate(&best_dst_fmt)) ?
+ ast_format_rate(&best_src_fmt) : ast_format_rate(&best_dst_fmt);
+
+ /* pick the best signed linear format based upon what preserves the sample rate the best. */
+ ast_format_set(&best_src_fmt, ast_format_slin_by_rate(best_sample_rate), 0);
+ }
+ }
+
+ if (ast_set_read_format(from, &best_src_fmt)) {
+ ast_log(LOG_WARNING, "Unable to set read format on channel %s to %s\n",
+ ast_channel_name(from), ast_getformatname(&best_src_fmt));
return -1;
}
- if (ast_set_write_format(to, &best_dst_fmt) < 0) {
- ast_log(LOG_WARNING, "Unable to set write format on channel %s to %s\n", ast_channel_name(to), ast_getformatname(&best_dst_fmt));
+ if (ast_set_write_format(to, &best_src_fmt)) {
+ ast_log(LOG_WARNING, "Unable to set write format on channel %s to %s\n",
+ ast_channel_name(to), ast_getformatname(&best_src_fmt));
return -1;
}
return 0;
@@ -6196,19 +6222,20 @@
int ast_channel_make_compatible(struct ast_channel *chan, struct ast_channel *peer)
{
- /* Some callers do not check return code, and we must try to set all call legs correctly */
- int rc = 0;
+ /*
+ * Set up translation from the peer to the chan first in case we
+ * need to hear any in-band tones and the other direction fails.
+ */
+ if (ast_channel_make_compatible_helper(peer, chan)) {
+ return -1;
+ }
/* Set up translation from the chan to the peer */
- rc = ast_channel_make_compatible_helper(chan, peer);
-
- if (rc < 0)
- return rc;
-
- /* Set up translation from the peer to the chan */
- rc = ast_channel_make_compatible_helper(peer, chan);
-
- return rc;
+ if (ast_channel_make_compatible_helper(chan, peer)) {
+ return -1;
+ }
+
+ return 0;
}
int ast_channel_masquerade(struct ast_channel *original, struct ast_channel *clonechan)
Modified: branches/12/res/res_fax.c
URL: http://svnview.digium.com/svn/asterisk/branches/12/res/res_fax.c?view=diff&rev=401239&r1=401238&r2=401239
==============================================================================
--- branches/12/res/res_fax.c (original)
+++ branches/12/res/res_fax.c Fri Oct 18 11:52:32 2013
@@ -3057,12 +3057,12 @@
ast_channel_unlock(chan);
peer = ast_channel_bridge_peer(chan);
- ast_channel_lock(chan);
if (peer) {
ast_set_read_format(peer, &gateway->peer_read_format);
ast_set_read_format(peer, &gateway->peer_write_format);
ast_channel_make_compatible(chan, peer);
}
+ ast_channel_lock(chan);
}
return NULL;
}
@@ -3084,7 +3084,7 @@
return f;
}
- if (!gateway->bridged && peer) {
+ if (!gateway->bridged) {
/* don't start a gateway if neither channel can handle T.38 */
if (ast_channel_get_t38_state(chan) == T38_STATE_UNAVAILABLE && ast_channel_get_t38_state(peer) == T38_STATE_UNAVAILABLE) {
ast_debug(1, "not starting gateway for %s and %s; neither channel supports T.38\n", ast_channel_name(chan), ast_channel_name(peer));
@@ -3113,10 +3113,12 @@
ast_set_read_format_by_id(chan, AST_FORMAT_SLINEAR);
ast_set_write_format_by_id(chan, AST_FORMAT_SLINEAR);
+ ast_channel_unlock(chan);
ast_set_read_format_by_id(peer, AST_FORMAT_SLINEAR);
ast_set_write_format_by_id(peer, AST_FORMAT_SLINEAR);
ast_channel_make_compatible(chan, peer);
+ ast_channel_lock(chan);
gateway->bridged = 1;
}
@@ -3381,10 +3383,10 @@
ast_set_read_format(chan, &faxdetect->orig_format);
ast_channel_unlock(chan);
peer = ast_channel_bridge_peer(chan);
- ast_channel_lock(chan);
if (peer) {
ast_channel_make_compatible(chan, peer);
}
+ ast_channel_lock(chan);
return NULL;
case AST_FRAMEHOOK_EVENT_READ:
if (f) {
More information about the asterisk-commits
mailing list