Merge the changes from the /team/group/vldtmf_fixup branch.

The main bug being addressed here is a problem introduced when two SIP
channels using SIP INFO dtmf have their media directly bridged.  So, when a
DTMF END frame comes into Asterisk from an incoming INFO message, Asterisk
would try to emulate a digit of some length by first sending a DTMF BEGIN
frame and sending a DTMF END later timed off of incoming audio.  However,
since there was no audio coming in, the DTMF_END was never generated.  This
caused DTMF based features to no longer work.

To fix this, the core now knows when a channel doesn't care about DTMF BEGIN
frames (such as a SIP channel sending INFO dtmf).  If this is the case, then
Asterisk will not emulate a digit of some length, and will instead just pass
through the single DTMF END event.

Channel drivers also now get passed the length of the digit to their digit_end
callback.  This improves SIP INFO support even further by enabling us to put
the real digit duration in the INFO message instead of a hard coded 250ms.
Also, for an incoming INFO message, the duration is read from the frame and
passed into the core instead of just getting ignored.

(issue #8597, maybe others...)


git-svn-id: http://svn.digium.com/svn/asterisk/branches/1.4@51311 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 20 insertions, 16 deletions

diff --git a/include/asterisk/channel.h b/include/asterisk/channel.h
index 431f57144..efa06bafb 100644
--- a/include/asterisk/channel.h
+++ b/include/asterisk/channel.h
@@ -204,7 +204,7 @@ struct ast_channel_tech {
 	int (* const send_digit_begin)(struct ast_channel *chan, char digit);
 
 	/*! \brief Stop sending a literal DTMF digit */
-	int (* const send_digit_end)(struct ast_channel *chan, char digit);
+	int (* const send_digit_end)(struct ast_channel *chan, char digit, unsigned int duration);
 
 	/*! \brief Call a given phone number (address, etc), but don't
 	   take longer than timeout seconds to do so.  */
@@ -427,7 +427,8 @@ struct ast_channel {
 	struct ast_jb jb;				/*!< The jitterbuffer state  */
 
 	char emulate_dtmf_digit;			/*!< Digit being emulated */
-	unsigned int emulate_dtmf_samples;		/*!< Number of samples left to emulate DTMF for */
+	unsigned int emulate_dtmf_duration;	/*!< Number of ms left to emulate DTMF for */
+	struct timeval dtmf_begin_tv;       /*!< The time that an in process digit began */
 
 	/*! \brief Data stores on the channel */
 	AST_LIST_HEAD_NOLOCK(datastores, ast_datastore) datastores;
@@ -446,34 +447,37 @@ enum {
 /*! \brief ast_channel flags */
 enum {
 	/*! Queue incoming dtmf, to be released when this flag is turned off */
-	AST_FLAG_DEFER_DTMF =   (1 << 1),
+	AST_FLAG_DEFER_DTMF =    (1 << 1),
 	/*! write should be interrupt generator */
-	AST_FLAG_WRITE_INT =    (1 << 2),
+	AST_FLAG_WRITE_INT =     (1 << 2),
 	/*! a thread is blocking on this channel */
-	AST_FLAG_BLOCKING =     (1 << 3),
+	AST_FLAG_BLOCKING =      (1 << 3),
 	/*! This is a zombie channel */
-	AST_FLAG_ZOMBIE =       (1 << 4),
+	AST_FLAG_ZOMBIE =        (1 << 4),
 	/*! There is an exception pending */
-	AST_FLAG_EXCEPTION =    (1 << 5),
+	AST_FLAG_EXCEPTION =     (1 << 5),
 	/*! Listening to moh XXX anthm promises me this will disappear XXX */
-	AST_FLAG_MOH =          (1 << 6),
+	AST_FLAG_MOH =           (1 << 6),
 	/*! This channel is spying on another channel */
-	AST_FLAG_SPYING =       (1 << 7),
+	AST_FLAG_SPYING =        (1 << 7),
 	/*! This channel is in a native bridge */
-	AST_FLAG_NBRIDGE =      (1 << 8),
+	AST_FLAG_NBRIDGE =       (1 << 8),
 	/*! the channel is in an auto-incrementing dialplan processor,
 	 *  so when ->priority is set, it will get incremented before
 	 *  finding the next priority to run */
-	AST_FLAG_IN_AUTOLOOP =  (1 << 9),
+	AST_FLAG_IN_AUTOLOOP =   (1 << 9),
 	/*! This is an outgoing call */
-	AST_FLAG_OUTGOING =     (1 << 10),
+	AST_FLAG_OUTGOING =      (1 << 10),
 	/*! This channel is being whispered on */
-	AST_FLAG_WHISPER =      (1 << 11),
+	AST_FLAG_WHISPER =       (1 << 11),
 	/*! A DTMF_BEGIN frame has been read from this channel, but not yet an END */
-	AST_FLAG_IN_DTMF =      (1 << 12),
+	AST_FLAG_IN_DTMF =       (1 << 12),
 	/*! A DTMF_END was received when not IN_DTMF, so the length of the digit is 
 	 *  currently being emulated */
-	AST_FLAG_EMULATE_DTMF = (1 << 13),
+	AST_FLAG_EMULATE_DTMF =  (1 << 13),
+	/*! This is set to tell the channel not to generate DTMF begin frames, and
+	 *  to instead only generate END frames. */
+	AST_FLAG_END_DTMF_ONLY = (1 << 14),
 };
 
 /*! \brief ast_bridge_config flags */
@@ -887,7 +891,7 @@ int ast_recvchar(struct ast_channel *chan, int timeout);
 int ast_senddigit(struct ast_channel *chan, char digit);
 
 int ast_senddigit_begin(struct ast_channel *chan, char digit);
-int ast_senddigit_end(struct ast_channel *chan, char digit);
+int ast_senddigit_end(struct ast_channel *chan, char digit, unsigned int duration);
 
 /*! \brief Receives a text string from a channel
  * Read a string of text from a channel