diff --git a/include/asterisk/dsp.h b/include/asterisk/dsp.h index 10ed53d1b1..6f635a83d8 100644 --- a/include/asterisk/dsp.h +++ b/include/asterisk/dsp.h @@ -115,4 +115,16 @@ int ast_dsp_get_tstate(struct ast_dsp *dsp); /*! \brief Get tcount (Threshold counter) */ int ast_dsp_get_tcount(struct ast_dsp *dsp); +/*! + * \brief Hint that a frame from a dsp was freed + * + * This is called from ast_frame_free if AST_FRFLAG_FROM_DSP is set. This occurs + * because it is possible for the dsp to be freed while someone still holds a reference + * to the frame that is in that dsp. This has been known to happen when the dsp on a Zap + * channel detects a busy signal. The channel is hung up, and the application that read the + * frame to begin with still has a reference to the frame. + * + * \return nothing + */ +void ast_dsp_frame_freed(struct ast_frame *fr); #endif /* _ASTERISK_DSP_H */ diff --git a/include/asterisk/frame.h b/include/asterisk/frame.h index ad4b829200..719048b02c 100644 --- a/include/asterisk/frame.h +++ b/include/asterisk/frame.h @@ -130,6 +130,10 @@ enum { * The translator can not be free'd if the frame inside of it still has * this flag set. */ AST_FRFLAG_FROM_TRANSLATOR = (1 << 1), + /*! This frame came from a dsp and is still the original frame. + * The dsp cannot be free'd if the frame inside of it still has + * this flag set. */ + AST_FRFLAG_FROM_DSP = (1 << 2), }; /*! \brief Data structure associated with a single frame of data diff --git a/main/dsp.c b/main/dsp.c index 6945464d47..f24030ebbd 100644 --- a/main/dsp.c +++ b/main/dsp.c @@ -1241,6 +1241,7 @@ struct ast_frame *ast_dsp_process(struct ast_channel *chan, struct ast_dsp *dsp, memset(&dsp->f, 0, sizeof(dsp->f)); dsp->f.frametype = AST_FRAME_NULL; ast_frfree(af); + ast_set_flag(&dsp->f, AST_FRFLAG_FROM_DSP); return &dsp->f; } if ((dsp->features & DSP_FEATURE_BUSY_DETECT) && ast_dsp_busydetect(dsp)) { @@ -1250,6 +1251,7 @@ struct ast_frame *ast_dsp_process(struct ast_channel *chan, struct ast_dsp *dsp, dsp->f.subclass = AST_CONTROL_BUSY; ast_frfree(af); ast_debug(1, "Requesting Hangup because the busy tone was detected on channel %s\n", chan->name); + ast_set_flag(&dsp->f, AST_FRFLAG_FROM_DSP); return &dsp->f; } if (((dsp->features & DSP_FEATURE_DTMF_DETECT) || (dsp->features & DSP_FEATURE_FAX_DETECT))) { @@ -1271,6 +1273,7 @@ struct ast_frame *ast_dsp_process(struct ast_channel *chan, struct ast_dsp *dsp, if (chan) ast_queue_frame(chan, af); ast_frfree(af); + ast_set_flag(&dsp->f, AST_FRFLAG_FROM_DSP); return &dsp->f; } } else { @@ -1297,6 +1300,7 @@ struct ast_frame *ast_dsp_process(struct ast_channel *chan, struct ast_dsp *dsp, ast_queue_frame(chan, af); ast_frfree(af); } + ast_set_flag(&dsp->f, AST_FRFLAG_FROM_DSP); return &dsp->f; } else { memset(&dsp->f, 0, sizeof(dsp->f)); @@ -1314,6 +1318,7 @@ struct ast_frame *ast_dsp_process(struct ast_channel *chan, struct ast_dsp *dsp, if (chan) ast_queue_frame(chan, af); ast_frfree(af); + ast_set_flag(&dsp->f, AST_FRFLAG_FROM_DSP); return &dsp->f; } } @@ -1331,6 +1336,7 @@ struct ast_frame *ast_dsp_process(struct ast_channel *chan, struct ast_dsp *dsp, if (chan) ast_queue_frame(chan, af); ast_frfree(af); + ast_set_flag(&dsp->f, AST_FRFLAG_FROM_DSP); return &dsp->f; } } @@ -1403,6 +1409,17 @@ void ast_dsp_set_features(struct ast_dsp *dsp, int features) void ast_dsp_free(struct ast_dsp *dsp) { + if (ast_test_flag(&dsp->f, AST_FRFLAG_FROM_DSP)) { + /* If this flag is still set, that means that the dsp's destruction + * been torn down, while we still have a frame out there being used. + * When ast_frfree() gets called on that frame, this ast_trans_pvt + * will get destroyed, too. */ + + /* Set the magic flag to destroy the dsp when the frame is freed */ + dsp->freqcount = -1; + + return; + } ast_free(dsp); } @@ -1516,3 +1533,17 @@ int ast_dsp_get_tcount(struct ast_dsp *dsp) { return dsp->tcount; } + +void ast_dsp_frame_freed(struct ast_frame *fr) +{ + struct ast_dsp *dsp; + + ast_clear_flag(fr, AST_FRFLAG_FROM_DSP); + + dsp = (struct ast_dsp *) (((char *) fr) - offsetof(struct ast_dsp, f)); + + if (dsp->freqcount != -1) + return; + + ast_dsp_free(dsp); +} diff --git a/main/frame.c b/main/frame.c index 07ce936f2c..dc471eebe6 100644 --- a/main/frame.c +++ b/main/frame.c @@ -37,6 +37,7 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$") #include "asterisk/threadstorage.h" #include "asterisk/linkedlists.h" #include "asterisk/translate.h" +#include "asterisk/dsp.h" #ifdef TRACE_FRAMES static int headers; @@ -308,6 +309,8 @@ void ast_frame_free(struct ast_frame *fr, int cache) { if (ast_test_flag(fr, AST_FRFLAG_FROM_TRANSLATOR)) ast_translate_frame_freed(fr); + else if (ast_test_flag(fr, AST_FRFLAG_FROM_DSP)) + ast_dsp_frame_freed(fr); if (!fr->mallocd) return; @@ -357,6 +360,7 @@ struct ast_frame *ast_frisolate(struct ast_frame *fr) void *newdata; ast_clear_flag(fr, AST_FRFLAG_FROM_TRANSLATOR); + ast_clear_flag(fr, AST_FRFLAG_FROM_DSP); if (!(fr->mallocd & AST_MALLOCD_HDR)) { /* Allocate a new header if needed */