Commit Graph

5272 Commits

Author SHA1 Message Date
George Joseph
d82a4b098f dns: Use ntohl for ans->ttl in dns_parse_answer_ex
dns_parse_answer_ex was not converting ans->ttl from network
by order to host byte order which was causing certain ttls
it to go negative. In turn this was causing answer edit checks
to fail.

ASTERISK-25528 #close
Reported-by: Daniel Tryba
Tested-by: George Joseph

Change-Id: I31505132d6321c46d2f39fd06c20ee808a864037
2015-11-06 13:19:11 -07:00
Walter Doekes
74e7333317 xmldoc: Improve xmldoc wrapping of 'core show ...' output.
Previously, the wrapping did both lookahead and lookback, which,
together with color escape sequences, caused some lines to be wrapped
way earlier than other lines.  This led to inconsistent output.

This simplifies the wrapping code and makes it more sane: if maxcolumns
is hit, we simply jump back to the last space and wrap there.

ASTERISK-25527 #close

Change-Id: I56d01c6f9a812642b1b05535c98d4db48d17c957
2015-11-06 08:46:24 -05:00
Jonathan Rose
a2c2a8e1bb taskprocessor: Add high water mark warnings
If a taskprocessor's queue grows large, this can indicate that there
may be a problem with tasks not leaving the processor or else that
the number of available task processors for a given type of task is
too low. This patch makes it so that if a taskprocessor's task queue
grows above 100 queued tasks that it will emit a warning message.
Warning messages are emitted only once per task processor.

ASTERISK-25518 #close
Reported by: Jonathan Rose

Change-Id: Ib1607c35d18c1d6a0575b3f0e3ff5d932fd6600c
2015-11-05 16:20:40 -06:00
Matt Jordan
9c293b5104 main/dial: Protect access to the format_cap structure of the requesting channel
When a dial attempt is made that involves a requesting channel, we previously
were not:
a) Protecting access to the native format capabilities structure on the
   requesting channel. That is inherently unsafe.
b) Reference bumping the lifetime of the format capabilities structure.

In both cases, something else could sneak in, blow away the format
capabilities, and we'd be holding onto an invalid format_cap structure. When
the newly created channel attempts to construct its format capabilities, things
go poorly.

This patch:
a) Ensures that we get a reference to the native format capabilities while
   the requesting channel is locked
b) Holds a reference to the native format capabilities during the creation
   of the new channel.

ASTERISK-25522 #close

Change-Id: I0bfb7ba8b9711f4158cbeaae96edf9626e88a54f
2015-11-04 15:42:32 -05:00
Corey Farrell
b0bf189908 Fix cli display of build options.
A previous commit reduced the AST_BUILDOPTS compiler define to
only include options that affected ABI.  This included some options
that were previously displayed by cli "core show settings".  This
change corrects the CLI display while still restricting buildopts.h
to ABI effecting options only.

ASTERISK-25434 #close
Reported by: Rusty Newton

Change-Id: Id07af6bedd1d7d325878023e403fbd9d3607e325
2015-11-04 09:15:51 -05:00
Matt Jordan
e26a06c1da main/stasis_endpoints: Fix ContactStatusChange JSON for roundtrip_usec field
The JSON packing for the ContactStatusChange event forgot to include the
roundtrip_usec field. As a result, the field never showed up in any event,
even when the data was available. This patch corrects that error by properly
packing the JSON blob with the data.

Change-Id: I8df80da659a44010afbd48f645967518ff5daa17
2015-11-03 09:18:41 -05:00
Matt Jordan
6b1e9fbdcf Merge "format: Update the maximum packetization time for iLBC 30." 2015-10-26 10:50:10 -05:00
Joshua Colp
d73bd56b0a Merge topic 'fix_oom_crash'
* changes:
  strings.c: Fix __ast_str_helper() to always return a terminated string.
  Add missing failure checks to ast_str_set_va() callers.
2015-10-23 06:51:18 -05:00
Mark Michelson
5dd9e1938a format_cap: Detect vector allocation failures.
A crash was seen on a system that ran out of memory due to Asterisk not
checking for vector allocation failures in format_cap.c. With this
change, if either of the AST_VECTOR_INIT calls fail, we will return a
value indicating failure.

Change-Id: Ieb9c59f39dfde6d11797a92b45e0cf8ac5722bc8
2015-10-22 17:29:15 -05:00
Richard Mudgett
1ce62b2545 strings.c: Fix __ast_str_helper() to always return a terminated string.
Users of functions which call __ast_str_helper() such as the ones listed
below are likely to not check the return value for failure so ensuring
that the string is always nil terminated is a good safety measure.

ast_str_set_va()
ast_str_append_va()
ast_str_set()
ast_str_append()

Change-Id: I36ab2d14bb6015868b49329dda8639d70fbcae07
2015-10-21 16:49:13 -05:00
Richard Mudgett
a04d946eaa Add missing failure checks to ast_str_set_va() callers.
Change-Id: I0c2cdcd53727bdc6634095c61294807255bd278f
2015-10-21 16:49:13 -05:00
Alexander Traud
f9cbac7321 format: Update the maximum packetization time for iLBC 30.
In September 2006, the maximum packetization time (ptime) were set to such a
low value, packetization was disabled for many codecs actually. This was fixed
for many codecs but not for iLBC 30. This enables packetization for iLBC which
can be enabled for example via allow=ilbc:60,gsm,alaw,ulaw in the file sip.conf.

ASTERISK-7803

Change-Id: I2ef90023d35efb7cb8fe96ed74f53f6846ffad12
2015-10-21 12:10:36 -05:00
Jonh Wendell
77780790e0 main/cdr: Allow modules to modify CDR fields before dispatching them
This patch adds the functions

	ast_cdr_modifier_register()
	ast_cdr_modifier_unregister()

That work much like ast_cdr_register() and ast_cdr_unregister().

Modules registered will be given a chance to modify (or to do whatever
they want) CDR fields just before they are passed to registered engines.

Thus, for instance, if a module change the "userfield" field of a CDR,
the modified value will be passed to every registered CDR backend for
logging.

ASTERISK-25479 #close

Change-Id: If11d8fd19ef89b1a66ecacf1201e10fcf86ccd56
2015-10-20 12:12:50 -05:00
Richard Mudgett
984f100dab config.c: Fix off-nominal memory leak.
Change-Id: I06e346e9a5c63cc5071e7eda537310c4b43bffe0
2015-10-12 15:11:39 -05:00
Richard Mudgett
9951255775 config.c: Fix potential memory corruption after [section](+).
The memory corruption could happen if the [section](+) is the last section
in the file with trailing comments.  In this case process_text_line() has
left *last_cat is set to newcat and newcat is destroyed.

Change-Id: I0d1d999f553986f591becd000e7cc6ddfb978d93
2015-10-12 15:11:39 -05:00
Richard Mudgett
c1ed11ee31 config.c: Fix #include after [section](+).
An #include right after a [section](+) would associate any variable
assignments before a new section in the #include with the wrong section.

* Fix section association by setting the current section to the appended
section.

* Fix '+' and '!' section flag interaction corner case depending upon
which flag came first.  If the '!' came first then it would be ignored.
If the '!' came after then it would affect the appended section.  The '!'
will now no longer be ignored.

ASTERISK-25461 #close
Reported by: Sean Pimental

Change-Id: Ic9d3191c8758048e2cbce6432f854b32531731c3
2015-10-12 15:11:39 -05:00
Ivan Poddubny
89dec7675d manager: Fix GetConfigJSON returning invalid JSON
When GetConfigJSON was introduced back in 1.6, it returned each
section as an array of strings: ["key=value", "key2=value2"].
Afterwards, it was changed a few times and became
["key": "value", "key2": "value2"], which is not a correct JSON.
This patch fixes that by constructing a JSON object {} instead of
an array [].

Also, the keys "istemplate" and "tempates" that are used to
indicate templates and their inherited categories are now wrapped in
quotes.

ASTERISK-25391 #close
Reported by: Bojan Nemčić

Change-Id: Ibbe93c6a227dff14d4a54b0d152341857bcf6ad8
2015-10-03 15:15:52 +03:00
Richard Mudgett
9bc7386b7c sched.c: Add warning about negative time interval request.
Change-Id: Ib91435fb45b7f5f7c0fc83d0eec20b88098707bc
2015-09-30 10:47:12 -05:00
Matt Jordan
2d7a4a3357 main/logger: Add log formatters and JSON structured logs
When Asterisk is part of a larger distributed system, log files are often
gathered using tools (such as logstash) that prefer to consume information
and have it rendered using other tools (such as Kibana) that prefer a
structured format, e.g., JSON. This patch adds support for JSON formatted
logs by adding support for an optional log format specifier in Asterisk's
logging subsystem. By adding a format specifier of '[json]':

full => [json]debug,verbose,notice,warning,error

Log messages will be output to the 'full' channel in the following
format:

{
  "hostname": Hostname or name specified in asterisk.conf
  "timestamp": Date/Time
  "identifiers": {
    "lwp": Thread ID,
    "callid": Call Identifier
  }
  "logmsg": {
    "location": {
      "filename": Name of the file that generated the log statement
      "function": Function that generated the log statement
      "line": Line number that called the logging function
    }
    "level": Log level, e.g., DEBUG, VERBOSE, etc.
    "message": Actual text of the log message
  }
}

ASTERISK-25425 #close

Change-Id: I8649bfedf3fb7bf3138008cc11565553209cc238
2015-09-29 07:28:01 -05:00
Matt Jordan
df7cfc9ac9 Merge "translate: Fix transcoding while different in frame size." 2015-09-28 16:24:19 -05:00
Joshua Colp
6392fdf6dc Merge "logger: Prevent duplicate dynamic channels from being added." 2015-09-25 10:57:40 -05:00
Mark Michelson
3eefa07a39 logger: Prevent duplicate dynamic channels from being added.
There was a problem observed where the "logger add channel" CLI command
would allow for a channel with the same name to be added multiple times.
This would result in each message being written out to the same file
multiple times.

The problem was due to the difference in how logger channel filenames
are stored versus the format they are allowed to be presented when they
are added. For instance, if adding the logger channel "foo" through the
CLI, the result would be a logger channel with the file name
/var/log/asterisk/foo being stored. So when trying to add another "foo"
channel, "foo" would not match "/var/log/asterisk/foo" so we'd happily
add the duplicate channel.

The fix presented here is to introduce two new methods in the logger
code:
 * make_filename(): given a logger channel name, this creates the
   filename for that logger channel.
 * find_logchannel(): given a logger channel name, this calls
   make_filename() and then traverses the list of logchannels in order
   to find a match.

This change has made use of make_filename() and find_logchannel()
throughout to more consistently behave.

ASTERISK-25305 #close
Reported by Mark Michelson

Change-Id: I892d52954d6007d8bc453c3cbdd9235dec9c4a36
2015-09-24 15:05:13 -05:00
Mark Michelson
f42084be09 Do not swallow frames on channels leaving bridges.
When leaving a bridge, indications on a channel could be swallowed by
the internal indication logic because it appears that the channel is on
its way to be hung up anyway. One such situation where this is
detrimental is when channels on hold are redirected out of a bridge. The
AST_CONTROL_UNHOLD indication from the bridging code is swallowed,
leaving the channel in question to still appear to be on hold.

The fix here is to modify the logic inside ast_indicate_data() to not
drop the indication if the channel is simply leaving a bridge. This way,
channels on hold redirected out of a bridge revert to their expected "in
use" state after the redirection.

ASTERISK-25418 #close
Reported by Mark Michelson

Change-Id: If6115204dfa0551c050974ee138fabd15f978949
2015-09-24 15:00:27 -05:00
Matt Jordan
6f719bb4d0 Merge "ARI: Add events for Contact and Peer Status changes" 2015-09-23 12:56:26 -05:00
Richard Mudgett
06f4f80a63 app_page.c: Fix crash when forwarding with a predial handler.
Page uses the async method of dialing with the dial API.  When a call gets
forwarded there is no calling channel available.  If the predial handler
was set then the calling channel could not be put into auto-service
for the forwarded call because it doesn't exist.  A crash is the result.

* Moved the callee predial parameter string processing to before the
string is passed to the dial API rather than having the dial API do it.
There are a few benefits do doing this.  The first is the predial
parameter string processing doesn't need to be done for each channel
called by the dial API.  The second is in async mode and the forwarded
channel is to have the predial handler executed on it then the
non-existent calling channel does not need to be present to process the
predial parameter string.

* Don't start auto-service on a non-existent calling channel to execute
the predial handler when the dial API is in async mode and forwarding a
call.

ASTERISK-25384 #close
Reported by: Chet Stevens

Change-Id: If53892b286d29f6cf955e2545b03dcffa2610981
2015-09-22 17:32:03 -05:00
Matt Jordan
069813db3c Merge "core/logging: Fix logging to more than one syslog channel" 2015-09-22 13:20:40 -05:00
Joshua Colp
4effba0d0a Merge "pbx: Update device and presence state when changing a hint extension." 2015-09-22 05:29:52 -05:00
Joshua Colp
4c2b77618c Merge "astfd: Adds a timestamp for each entry." 2015-09-21 08:43:45 -05:00
Elazar Broad
a29cf45c76 core/logging: Fix logging to more than one syslog channel
Currently, Asterisk will log to the last configured syslog
channel in logger.conf. This is due to the fact that the
final call to openlog() supersedes all of the previous calls.
This commit removes the call to openlog() and passes the
facility to ast_log_vsyslog(), along with utilizing the
LOG_MAKEPRI macro to ensure that the message is routed to
the correct facility and with the correct priority.

ASTERISK-25407 #close
Reported by: Elazar Broad
Tested by: Elazar Broad

Change-Id: Ie2a2416bc00cce1b04e99ef40917c2011953ddd2
2015-09-21 08:37:06 -05:00
Matt Jordan
5206aa9d30 ARI: Add events for Contact and Peer Status changes
This patch adds support for receiving events regarding Peer status changes
and Contact status changes. This is particularly useful in scenarios where
we are subscribed to all endpoints and channels, where we often want to know
more about the state of channel technology specific items than a single
endpoint's state.

ASTERISK-24870

Change-Id: I6137459cdc25ce27efc134ad58abf065653da4e9
2015-09-21 08:21:58 -05:00
Matt Jordan
5541c6de6e Merge "main/config_options: Check for existance of internal object before derefing" 2015-09-21 08:08:36 -05:00
Alexander Traud
9200ad03a3 astfd: Adds a timestamp for each entry.
Now with menuselect "DEBUG_FD_LEAKS" and CLI "core show fd", a timestamp is
shown with each file descriptor. This helps to debug leaked UDP/TCP ports on
long-lived servers, for example.

ASTERISK-25405 #close

Change-Id: I968339e5155a512eba1032a5263f1ec8b5e1f80b
2015-09-19 19:52:36 +02:00
Joshua Colp
42a897c4c3 pbx: Update device and presence state when changing a hint extension.
When changing a hint extension without removing the hint first the
device state and presence state is not updated. This causes the state
of the hint to be that of the previous extension and not the current
one. This state is kept until a state change occurs as a result of
something (presence state change, device state change).

This change updates the hint with the current device and presence
state of the new extension when it is changed. Any state callbacks
which may have been added before the hint extension is changed are
also informed of the new device and presence state if either have
changed.

ASTERISK-25394 #close

Change-Id: If268f1110290e502c73dd289c9e7e7b27bc8432f
2015-09-19 08:20:51 -05:00
Alexander Traud
077adf48b8 translate: Fix transcoding while different in frame size.
When Asterisk translates between codecs, each with a different frame size (for
example between iLBC 30 and Speex-WB), too large frames were created by
ast_trans_frameout. Now, ast_trans_frameout is called with the correct frame
length, creating several frames when necessary. Affects all transcoding modules
which used ast_trans_frameout: GSM, iLBC, LPC10, and Speex.

ASTERISK-25353 #close

Change-Id: I2e229569d73191d66a4e43fef35432db24000212
2015-09-17 16:58:57 +02:00
Mark Michelson
0a74c80300 scheduler: Use queue for allocating sched IDs.
It has been observed that on long-running busy systems, a scheduler
context can eventually hit INT_MAX for its assigned IDs and end up
overflowing into a very low negative number. When this occurs, this can
result in odd behaviors, because a negative return is interpreted by
callers as being a failure. However, the item actually was successfully
scheduled. The result may be that a freed item remains in the scheduler,
resulting in a crash at some point in the future.

The scheduler can overflow because every time that an item is added to
the scheduler, a counter is bumped and that counter's current value is
assigned as the new item's ID.

This patch introduces a new method for assigning scheduler IDs. Instead
of assigning from a counter, a queue of available IDs is maintained.
When assigning a new ID, an ID is pulled from the queue. When a
scheduler item is released, its ID is pushed back onto the queue. This
way, IDs may be reused when they become available, and the growth of ID
numbers is directly related to concurrent activity within a scheduler
context rather than the uptime of the system.

Change-Id: I532708eef8f669d823457d7fefdad9a6078b99b2
2015-09-15 13:28:05 -05:00
Matt Jordan
45cf79665c main/config_options: Check for existance of internal object before derefing
Asterisk can load and register an object type while still having an invalid
sorcery mapping. This can cause an issue when a creation call is invoked.
For example, mis-configuring PJSIP's endpoint identifier by IP address mapping
in sorcery.conf will cause the sorcery mechanism to be invalidated; however, a
subsequent ARI invocation to create the object will cause a crash, as the
internal type may not be registered as sorcery expects.

Merely checking for a NULL pointer here solves the issue.

Change-Id: I54079fb94a1440992f4735a9a1bbf1abb1c601ac
2015-09-11 16:21:07 -05:00
Joshua Colp
fdf77633ed Merge "Core/General: Add #ifdef needed on FreeBSD." 2015-09-08 16:11:00 -05:00
Scott Griepentrog
7691035312 endpoint snapshot: avoid second cleanup on alloc failure
In ast_endpoint_snapshot_create(), a failure to init the
string fields results in two attempts to ao2_cleanup the
same pointer.  Removed RAII_VAR to eliminate problem.

ASTERISK-25375 #close
Reported by: Scott Griepentrog

Change-Id: If4d9dfb1bbe3836b623642ec690b6d49b25e8979
2015-09-04 09:26:46 -05:00
Guido Falsi
fbdb42c9fc Core/General: Add #ifdef needed on FreeBSD.
pthread_attr_init() defaults to PTHREAD_EXPLICIT_SCHED on FreeBSD
too.

ASTERISK-25310 #close
Reported by: Guido Falsi

Change-Id: Iae6befac9028b5b9795f86986a4a08a1ae6ab7c4
2015-09-03 21:29:37 -05:00
Joshua Colp
b51cf1e712 pbx: Fix crash when issuing "core show hints" with long pattern match.
When issuing the "core show hints" CLI command a combination of both
the hint extension and context is created. This uses a fixed size
buffer expecting that the extension will not exceed maximum extension
length. When the extension is actually a pattern match this constraint
does not hold true, and the extension may exceed the maximum extension
length. In this case extra characters are written past the end of the
fixed size buffer.

This change makes it so the construction of the combined hint extension
and context can not exceed the size of the buffer.

ASTERISK-25367 #close

Change-Id: Idfa1b95d0d4dc38e675be7c1de8900b3f981f499
2015-09-02 12:47:51 -05:00
Joshua Colp
fc4d4f5379 taskprocessor: Fix race condition between unreferencing and finding.
When unreferencing a taskprocessor its reference count is checked
to determine if it should be unlinked from the taskprocessors
container and its listener shut down. In between the time when the
reference count is checked and unlinking it is possible for
another thread to jump in, find it, and get a reference to it. If
the thread then uses the taskprocessor it may find that it is not
in the state it expects.

This change locks the taskprocessors container during almost the
entire unreference operation to ensure that any other thread which
may attempt to find the taskprocessor has to wait.

ASTERISK-25295

Change-Id: Icb842db82fe1cf238da55df92e95938a4419377c
2015-08-29 10:44:27 -05:00
Joshua Colp
c036e50fbe sched: ast_sched_del may return prematurely due to spurious wakeup
When deleting a scheduled item if the item in question is currently
executing the ast_sched_del function waits until it has completed.
This is accomplished using ast_cond_wait. Unfortunately the
ast_cond_wait function can suffer from spurious wakeups so the
predicate needs to be checked after it returns to make sure it has
really woken up as a result of being signaled.

This change adds a loop around the ast_cond_wait to make sure that
it only exits when the executing task has really completed.

ASTERISK-25355 #close

Change-Id: I51198270eb0b637c956c61aa409f46283432be61
2015-08-28 20:04:53 -05:00
Joshua Colp
98d089fb9a bridge: Kick channel from bridge if hung up during action.
When executing an action in a bridge it is possible for the
channel to be hung up without the bridge becoming aware of it.
This is most easily reproducible by hanging up when the bridge
is streaming DTMF due to a feature timeout. This change makes
it so after action execution the channel is checked to determine
if it has been hung up and if it has it is kicked from the bridge.

ASTERISK-25341 #close

Change-Id: I6dd8b0c3f5888da1c57afed9e8a802ae0a053062
2015-08-24 11:12:57 -05:00
Richard Mudgett
f7df3e1a01 rtp_engine.c: Get current or create a needed rx payload type mapping.
* Make ast_rtp_codecs_payload_code() get the current mapping or create a
rx payload type mapping.

ASTERISK-25166
Reported by: Kevin Harwell

ASTERISK-17410
Reported by: Boris Fox

Change-Id: Ia4b2d45877a8f004f6ce3840e3d8afe533384e56
2015-08-20 11:56:13 -05:00
Richard Mudgett
38854a9f7b rtp_engine.c: Extract rtp_codecs_payload_replace_rx().
ASTERISK-25166
Reported by: Kevin Harwell

ASTERISK-17410
Reported by: Boris Fox

Change-Id: I34e23bf5b084c8570f9c3e6ccd19b95fe85af239
2015-08-19 17:09:58 -05:00
Richard Mudgett
1a549ed134 rtp_engine.c: Initial split of payload types into rx and tx mappings.
There are numerous problems with the current implementation of the RTP
payload type mapping in Asterisk.  It uses only one mapping structure to
associate payload types to codecs.  The single mapping is overkill if all
of the payload type values are well known values.  Dynamic payload type
mappings do not work as well with the single mapping because RFC3264
allows each side of the link to negotiate different dynamic mappings for
what they want to receive.  Not only could you have the same codec mapped
for sending and receiving on different payload types you could wind up
with the same payload type mapped to different codecs for each direction.

1) An independent payload type mapping is needed for sending and
receiving.

2) The receive mapping needs to keep track of previous mappings because of
the slack to when negotiation happens and current packets in flight using
the old mapping arrive.

3) The transmit mapping only needs to keep track of the current negotiated
values since we are sending the packets and know when the switchover takes
place.

* Needed to create ast_rtp_codecs_payload_code_tx() and make some callers
use the new function because ast_rtp_codecs_payload_code() was used for
mappings in both directions.

* Needed to create ast_rtp_codecs_payloads_xover() for cases where we need
to pass preferred codec mappings to the peer channel for early media
bridging or when we need to prefer the offered mapping that RFC3264 says
we SHOULD use.

* ast_rtp_codecs_payloads_xover() and ast_rtp_codecs_payload_code_tx() are
the only new public functions created.  All the others were only used for
the tx or rx mapping direction so the function doxygen now reflects which
direction the function operates.

* chan_mgcp.c: Removed call to ast_rtp_codecs_payloads_clear() as doing
that makes no sense when processing an incoming SDP.  We would be wiping
out any mappings that we set for the possible outgoing SDP we sent
earlier.

ASTERISK-25166
Reported by: Kevin Harwell

ASTERISK-17410
Reported by: Boris Fox

Change-Id: Iaf6c227bca68cb7c414cf2fd4108a8ac98bd45ac
2015-08-19 17:09:58 -05:00
Scott Griepentrog
178e1adffb CHAOS: prevent sorcery object with null id
When allocating a sorcery object, fail if the
id value was not allocated.

ASTERISK-25323
Reported by: Scott Griepentrog

Change-Id: I152133fb7545a4efcf7a0080ada77332d038669e
2015-08-17 11:03:06 -05:00
Richard Mudgett
7c4cb8618d audiohook.c: Simplify variable usage in audiohook_read_frame_both().
Change-Id: I58bed58631a94295b267991c5b61a3a93c167f0c
2015-08-13 17:59:18 -05:00
Richard Mudgett
bb37473234 audiohook.c: Fix MixMonitor crash when using the r() or t() options.
The built frame format in audiohook_read_frame_both() is now set to a
signed linear format before the rx and tx frames are duplicated instead of
only for the mixed audio frame duplication.

ASTERISK-25322 #close
Reported by Sean Pimental

Change-Id: I86f85b5c48c49e4e2d3b770797b9d484250a1538
2015-08-13 17:59:18 -05:00
Matt Jordan
e188192ad1 main/format: Add an API call for retrieving format attributes
Some codecs that may be a third party library to Asterisk need to have
knowledge of the format attributes that were negotiated. Unfortunately,
when the great format migration of Asterisk 13 occurred, that ability
was lost.

This patch adds an API call, ast_format_attribute_get, to the core
format API, along with updates to the unit test to check the new API
call. A new callback is also now available for format attribute modules,
such that they can provide the format attribute values they manage.

Note that the API returns a void *. This is done as the format attribute
modules themselves may store format attributes in any particular manner
they like. Care should be taken by consumers of the API to check the
return value before casting and dereferencing. Consumers will obviously
need to have a priori knowledge of the type of the format attribute as
well.

Change-Id: Ieec76883dfb46ecd7aff3dc81a52c81f4dc1b9e3
2015-08-10 12:47:56 -05:00