main/frame.c

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/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2005, Digium, Inc.
 *
 * Mark Spencer <[email protected]>
 *
 * See http://www.asterisk.org for more information about
 * the Asterisk project. Please do not directly contact
 * any of the maintainers of this project for assistance;
 * the project provides a web site, mailing lists and IRC
 * channels for your use.
 *
 * This program is free software, distributed under the terms of
 * the GNU General Public License Version 2. See the LICENSE file
 * at the top of the source tree.
 */

/*! \file
 *
 * \brief Frame and codec manipulation routines
 *
 * \author Mark Spencer <[email protected]>
 */

/*** MODULEINFO
   <support_level>core</support_level>
 ***/

#include "asterisk.h"

#include "asterisk/_private.h"
#include "asterisk/lock.h"
#include "asterisk/frame.h"
#include "asterisk/format_cache.h"
#include "asterisk/channel.h"
#include "asterisk/cli.h"
#include "asterisk/term.h"
#include "asterisk/utils.h"
#include "asterisk/threadstorage.h"
#include "asterisk/linkedlists.h"
#include "asterisk/translate.h"
#include "asterisk/dsp.h"
#include "asterisk/file.h"

#include <math.h>

#if (defined(LOW_MEMORY) || defined(MALLOC_DEBUG)) && !defined(NO_FRAME_CACHE)
#define NO_FRAME_CACHE
#endif

#if !defined(NO_FRAME_CACHE)
static void frame_cache_cleanup(void *data);

/*! \brief A per-thread cache of frame headers */
AST_THREADSTORAGE_CUSTOM(frame_cache, NULL, frame_cache_cleanup);

/*!
 * \brief Maximum ast_frame cache size
 *
 * In most cases where the frame header cache will be useful, the size
 * of the cache will stay very small.  However, it is not always the case that
 * the same thread that allocates the frame will be the one freeing them, so
 * sometimes a thread will never have any frames in its cache, or the cache
 * will never be pulled from.  For the latter case, we limit the maximum size.
 */
#define FRAME_CACHE_MAX_SIZE  10

/*! \brief This is just so ast_frames, a list head struct for holding a list of
 *  ast_frame structures, is defined. */
AST_LIST_HEAD_NOLOCK(ast_frames, ast_frame);

struct ast_frame_cache {
   struct ast_frames list;
   size_t size;
};
#endif

struct ast_frame ast_null_frame = { AST_FRAME_NULL, };

static struct ast_frame *ast_frame_header_new(const char *file, int line, const char *func)
{
   struct ast_frame *f;

#if !defined(NO_FRAME_CACHE)
   struct ast_frame_cache *frames;

   if ((frames = ast_threadstorage_get(&frame_cache, sizeof(*frames)))) {
      if ((f = AST_LIST_REMOVE_HEAD(&frames->list, frame_list))) {
         size_t mallocd_len = f->mallocd_hdr_len;

         memset(f, 0, sizeof(*f));
         f->mallocd_hdr_len = mallocd_len;
         frames->size--;
         return f;
      }
   }
#endif

   if (!(f = __ast_calloc(1, sizeof(*f), file, line, func))) {
      return NULL;
   }

   f->mallocd_hdr_len = sizeof(*f);

   return f;
}

#if !defined(NO_FRAME_CACHE)
static void frame_cache_cleanup(void *data)
{
   struct ast_frame_cache *frames = data;
   struct ast_frame *f;

   while ((f = AST_LIST_REMOVE_HEAD(&frames->list, frame_list)))
      ast_free(f);

   ast_free(frames);
}
#endif

static void __frame_free(struct ast_frame *fr, int cache)
{
   if (!fr->mallocd)
      return;

#if !defined(NO_FRAME_CACHE)
   if (fr->mallocd == AST_MALLOCD_HDR
      && cache
      && ast_opt_cache_media_frames) {
      /* Cool, only the header is malloc'd, let's just cache those for now
       * to keep things simple... */
      struct ast_frame_cache *frames;

      frames = ast_threadstorage_get(&frame_cache, sizeof(*frames));
      if (frames && frames->size < FRAME_CACHE_MAX_SIZE) {
         if (fr->frametype == AST_FRAME_VOICE
            || fr->frametype == AST_FRAME_VIDEO
            || fr->frametype == AST_FRAME_IMAGE) {
            ao2_cleanup(fr->subclass.format);
         } else if (fr->frametype == AST_FRAME_CONTROL && fr->subclass.integer == AST_CONTROL_ANSWER) {
            ao2_cleanup(fr->subclass.topology);
         }

         AST_LIST_INSERT_HEAD(&frames->list, fr, frame_list);
         frames->size++;
         return;
      }
   }
#endif

   if (fr->mallocd & AST_MALLOCD_DATA) {
      if (fr->data.ptr) {
         ast_free(fr->data.ptr - fr->offset);
      }
   }
   if (fr->mallocd & AST_MALLOCD_SRC) {
      ast_free((void *) fr->src);
   }
   if (fr->mallocd & AST_MALLOCD_HDR) {
      if (fr->frametype == AST_FRAME_VOICE
         || fr->frametype == AST_FRAME_VIDEO
         || fr->frametype == AST_FRAME_IMAGE) {
         ao2_cleanup(fr->subclass.format);
      } else if (fr->frametype == AST_FRAME_CONTROL && fr->subclass.integer == AST_CONTROL_ANSWER) {
         ao2_cleanup(fr->subclass.topology);
      }

      ast_free(fr);
   } else {
      fr->mallocd = 0;
   }
}


void ast_frame_free(struct ast_frame *frame, int cache)
{
   struct ast_frame *next;

   while (frame) {
      next = AST_LIST_NEXT(frame, frame_list);
      __frame_free(frame, cache);
      frame = next;
   }
}

void ast_frame_dtor(struct ast_frame *f)
{
   ast_frfree(f);
}

/*!
 * \brief 'isolates' a frame by duplicating non-malloc'ed components
 * (header, src, data).
 * On return all components are malloc'ed
 */
struct ast_frame *__ast_frisolate(struct ast_frame *fr, const char *file, int line, const char *func)
{
   struct ast_frame *out;
   void *newdata;

   /* if none of the existing frame is malloc'd, let ast_frdup() do it
      since it is more efficient
   */
   if (fr->mallocd == 0) {
      return __ast_frdup(fr, file, line, func);
   }

   /* if everything is already malloc'd, we are done */
   if ((fr->mallocd & (AST_MALLOCD_HDR | AST_MALLOCD_SRC | AST_MALLOCD_DATA)) ==
       (AST_MALLOCD_HDR | AST_MALLOCD_SRC | AST_MALLOCD_DATA)) {
      return fr;
   }

   if (!(fr->mallocd & AST_MALLOCD_HDR)) {
      /* Allocate a new header if needed */
      if (!(out = ast_frame_header_new(file, line, func))) {
         return NULL;
      }
      out->frametype = fr->frametype;
      out->subclass = fr->subclass;
      if ((fr->frametype == AST_FRAME_VOICE) || (fr->frametype == AST_FRAME_VIDEO) ||
         (fr->frametype == AST_FRAME_IMAGE)) {
         ao2_bump(out->subclass.format);
      } else if (fr->frametype == AST_FRAME_VOICE && fr->subclass.integer == AST_CONTROL_ANSWER) {
         ao2_bump(out->subclass.topology);
      }
      out->datalen = fr->datalen;
      out->samples = fr->samples;
      out->mallocd = AST_MALLOCD_HDR;
      out->offset = fr->offset;
      /* Copy the timing data */
      ast_copy_flags(out, fr, AST_FLAGS_ALL);
      if (ast_test_flag(fr, AST_FRFLAG_HAS_TIMING_INFO)) {
         out->ts = fr->ts;
         out->len = fr->len;
         out->seqno = fr->seqno;
      }
      out->stream_num = fr->stream_num;
   } else {
      out = fr;
   }

   if (fr->src) {
      /* The original frame has a source string */
      if (!(fr->mallocd & AST_MALLOCD_SRC)) {
         /*
          * The original frame has a non-malloced source string.
          *
          * Duplicate the string and put it into the isolated frame
          * which may also be the original frame.
          */
         newdata = ast_strdup(fr->src);
         if (!newdata) {
            if (out != fr) {
               ast_frame_free(out, 0);
            }
            return NULL;
         }
         out->src = newdata;
         out->mallocd |= AST_MALLOCD_SRC;
      } else if (out != fr) {
         /* Steal the source string from the original frame. */
         out->src = fr->src;
         fr->src = NULL;
         fr->mallocd &= ~AST_MALLOCD_SRC;
         out->mallocd |= AST_MALLOCD_SRC;
      }
   }

   if (!(fr->mallocd & AST_MALLOCD_DATA))  {
      /* The original frame has a non-malloced data buffer. */
      if (!fr->datalen && fr->frametype != AST_FRAME_TEXT) {
         /* Actually it's just an int so we can simply copy it. */
         out->data.uint32 = fr->data.uint32;
         return out;
      }
      /*
       * Duplicate the data buffer and put it into the isolated frame
       * which may also be the original frame.
       */
      newdata = ast_malloc(fr->datalen + AST_FRIENDLY_OFFSET);
      if (!newdata) {
         if (out != fr) {
            ast_frame_free(out, 0);
         }
         return NULL;
      }
      newdata += AST_FRIENDLY_OFFSET;
      out->offset = AST_FRIENDLY_OFFSET;
      memcpy(newdata, fr->data.ptr, fr->datalen);
      out->data.ptr = newdata;
      out->mallocd |= AST_MALLOCD_DATA;
   } else if (out != fr) {
      /* Steal the data buffer from the original frame. */
      out->data = fr->data;
      memset(&fr->data, 0, sizeof(fr->data));
      fr->mallocd &= ~AST_MALLOCD_DATA;
      out->mallocd |= AST_MALLOCD_DATA;
   }

   return out;
}

struct ast_frame *__ast_frdup(const struct ast_frame *f, const char *file, int line, const char *func)
{
   struct ast_frame *out = NULL;
   int len, srclen = 0;
   void *buf = NULL;

#if !defined(NO_FRAME_CACHE)
   struct ast_frame_cache *frames;
#endif

   /* Start with standard stuff */
   len = sizeof(*out) + AST_FRIENDLY_OFFSET + f->datalen;
   /* If we have a source, add space for it */
   /*
    * XXX Watch out here - if we receive a src which is not terminated
    * properly, we can be easily attacked. Should limit the size we deal with.
    */
   if (f->src)
      srclen = strlen(f->src);
   if (srclen > 0)
      len += srclen + 1;

#if !defined(NO_FRAME_CACHE)
   if ((frames = ast_threadstorage_get(&frame_cache, sizeof(*frames)))) {
      AST_LIST_TRAVERSE_SAFE_BEGIN(&frames->list, out, frame_list) {
         if (out->mallocd_hdr_len >= len) {
            size_t mallocd_len = out->mallocd_hdr_len;

            AST_LIST_REMOVE_CURRENT(frame_list);
            memset(out, 0, sizeof(*out));
            out->mallocd_hdr_len = mallocd_len;
            buf = out;
            frames->size--;
            break;
         }
      }
      AST_LIST_TRAVERSE_SAFE_END;
   }
#endif

   if (!buf) {
      if (!(buf = __ast_calloc(1, len, file, line, func)))
         return NULL;
      out = buf;
      out->mallocd_hdr_len = len;
   }

   out->frametype = f->frametype;
   out->subclass = f->subclass;
   if ((f->frametype == AST_FRAME_VOICE) || (f->frametype == AST_FRAME_VIDEO) ||
      (f->frametype == AST_FRAME_IMAGE)) {
      ao2_bump(out->subclass.format);
   } else if (f->frametype == AST_FRAME_CONTROL && f->subclass.integer == AST_CONTROL_ANSWER) {
      ao2_bump(out->subclass.topology);
   }

   out->datalen = f->datalen;
   out->samples = f->samples;
   out->delivery = f->delivery;
   /* Even though this new frame was allocated from the heap, we can't mark it
    * with AST_MALLOCD_HDR, AST_MALLOCD_DATA and AST_MALLOCD_SRC, because that
    * would cause ast_frfree() to attempt to individually free each of those
    * under the assumption that they were separately allocated. Since this frame
    * was allocated in a single allocation, we'll only mark it as if the header
    * was heap-allocated; this will result in the entire frame being properly freed.
    */
   out->mallocd = AST_MALLOCD_HDR;
   out->offset = AST_FRIENDLY_OFFSET;
   /* Make sure that empty text frames have a valid data.ptr */
   if (out->datalen || f->frametype == AST_FRAME_TEXT) {
      out->data.ptr = buf + sizeof(*out) + AST_FRIENDLY_OFFSET;
      memcpy(out->data.ptr, f->data.ptr, out->datalen);
   } else {
      out->data.uint32 = f->data.uint32;
   }
   if (srclen > 0) {
      /* This may seem a little strange, but it's to avoid a gcc (4.2.4) compiler warning */
      char *src;
      out->src = buf + sizeof(*out) + AST_FRIENDLY_OFFSET + f->datalen;
      src = (char *) out->src;
      /* Must have space since we allocated for it */
      strcpy(src, f->src);
   }
   ast_copy_flags(out, f, AST_FLAGS_ALL);
   out->ts = f->ts;
   out->len = f->len;
   out->seqno = f->seqno;
   out->stream_num = f->stream_num;
   return out;
}

void ast_swapcopy_samples(void *dst, const void *src, int samples)
{
   int i;
   unsigned short *dst_s = dst;
   const unsigned short *src_s = src;

   for (i = 0; i < samples; i++)
      dst_s[i] = (src_s[i]<<8) | (src_s[i]>>8);
}

char *ast_frame_subclass2str(struct ast_frame *f, char *subclass, size_t slen, char *moreinfo, size_t mlen)
{
   switch(f->frametype) {
   case AST_FRAME_DTMF_BEGIN:
      if (slen > 1) {
         subclass[0] = f->subclass.integer;
         subclass[1] = '\0';
      }
      break;
   case AST_FRAME_DTMF_END:
      if (slen > 1) {
         subclass[0] = f->subclass.integer;
         subclass[1] = '\0';
      }
      break;
   case AST_FRAME_CONTROL:
      switch (f->subclass.integer) {
      case AST_CONTROL_HANGUP:
         ast_copy_string(subclass, "Hangup", slen);
         break;
      case AST_CONTROL_RING:
         ast_copy_string(subclass, "Ring", slen);
         break;
      case AST_CONTROL_RINGING:
         ast_copy_string(subclass, "Ringing", slen);
         break;
      case AST_CONTROL_ANSWER:
         ast_copy_string(subclass, "Answer", slen);
         break;
      case AST_CONTROL_BUSY:
         ast_copy_string(subclass, "Busy", slen);
         break;
      case AST_CONTROL_TAKEOFFHOOK:
         ast_copy_string(subclass, "Take Off Hook", slen);
         break;
      case AST_CONTROL_OFFHOOK:
         ast_copy_string(subclass, "Line Off Hook", slen);
         break;
      case AST_CONTROL_CONGESTION:
         ast_copy_string(subclass, "Congestion", slen);
         break;
      case AST_CONTROL_FLASH:
         ast_copy_string(subclass, "Flash", slen);
         break;
      case AST_CONTROL_WINK:
         ast_copy_string(subclass, "Wink", slen);
         break;
      case AST_CONTROL_OPTION:
         ast_copy_string(subclass, "Option", slen);
         break;
      case AST_CONTROL_RADIO_KEY:
         ast_copy_string(subclass, "Key Radio", slen);
         break;
      case AST_CONTROL_RADIO_UNKEY:
         ast_copy_string(subclass, "Unkey Radio", slen);
         break;
      case AST_CONTROL_PROGRESS:
         ast_copy_string(subclass, "Progress", slen);
         break;
      case AST_CONTROL_PROCEEDING:
         ast_copy_string(subclass, "Proceeding", slen);
         break;
      case AST_CONTROL_HOLD:
         ast_copy_string(subclass, "Hold", slen);
         break;
      case AST_CONTROL_UNHOLD:
         ast_copy_string(subclass, "Unhold", slen);
         break;
      case AST_CONTROL_VIDUPDATE:
         ast_copy_string(subclass, "Video Update", slen);
         break;
      case AST_CONTROL_T38_PARAMETERS: {
         char *message = "Unknown";
         if (f->datalen != sizeof(struct ast_control_t38_parameters)) {
            message = "Invalid";
         } else {
            struct ast_control_t38_parameters *parameters = f->data.ptr;
            enum ast_control_t38 state = parameters->request_response;
            if (state == AST_T38_REQUEST_NEGOTIATE)
               message = "Negotiation Requested";
            else if (state == AST_T38_REQUEST_TERMINATE)
               message = "Negotiation Request Terminated";
            else if (state == AST_T38_NEGOTIATED)
               message = "Negotiated";
            else if (state == AST_T38_TERMINATED)
               message = "Terminated";
            else if (state == AST_T38_REFUSED)
               message = "Refused";
         }
         snprintf(subclass, slen, "T38_Parameters/%s", message);
         break;
      }

      case AST_CONTROL_STREAM_STOP:
         ast_copy_string(subclass, "Stop stream", slen);
         break;
      case AST_CONTROL_STREAM_SUSPEND:
         ast_copy_string(subclass, "Suspend stream", slen);
         break;
      case AST_CONTROL_STREAM_RESTART:
         ast_copy_string(subclass, "Restart stream", slen);
         break;
      case AST_CONTROL_STREAM_REVERSE:
         ast_copy_string(subclass, "Reverse stream", slen);
         break;
      case AST_CONTROL_STREAM_FORWARD:
         ast_copy_string(subclass, "Forward stream", slen);
         break;
      case AST_CONTROL_RECORD_CANCEL:
         ast_copy_string(subclass, "Cancel stream", slen);
         break;
      case AST_CONTROL_RECORD_STOP:
         ast_copy_string(subclass, "Record stop", slen);
         break;
      case AST_CONTROL_RECORD_SUSPEND:
         ast_copy_string(subclass, "Record suspend", slen);
         break;
      case AST_CONTROL_RECORD_MUTE:
         ast_copy_string(subclass, "Record mute", slen);
         break;
      case AST_CONTROL_SRCUPDATE:
         ast_copy_string(subclass, "Media source update", slen);
         break;
      case AST_CONTROL_TRANSFER:
         ast_copy_string(subclass, "Transfer", slen);
         break;
      case AST_CONTROL_CONNECTED_LINE:
         ast_copy_string(subclass, "Connected line update", slen);
         break;
      case AST_CONTROL_REDIRECTING:
         ast_copy_string(subclass, "Redirect", slen);
         break;
      case AST_CONTROL_CC:
         ast_copy_string(subclass, "CC", slen);
         break;
      case AST_CONTROL_SRCCHANGE:
         ast_copy_string(subclass, "Media SSRC change", slen);
         break;
      case AST_CONTROL_READ_ACTION:
         ast_copy_string(subclass, "Read action", slen);
         break;
      case AST_CONTROL_AOC:
         ast_copy_string(subclass, "AOC", slen);
         break;
      case AST_CONTROL_END_OF_Q:
         ast_copy_string(subclass, "Endof Q", slen);
         break;
      case AST_CONTROL_INCOMPLETE:
         ast_copy_string(subclass, "Incomplete", slen);
         break;
      case AST_CONTROL_MCID:
         ast_copy_string(subclass, "MCID", slen);
         break;
      case AST_CONTROL_UPDATE_RTP_PEER:
         ast_copy_string(subclass, "Update RTP peer", slen);
         break;
      case AST_CONTROL_PVT_CAUSE_CODE:
         ast_copy_string(subclass, "Private Cause Code", slen);
         break;
      case AST_CONTROL_MASQUERADE_NOTIFY:
         ast_copy_string(subclass, "Masquerade notify", slen);
         break;
      case AST_CONTROL_STREAM_TOPOLOGY_REQUEST_CHANGE:
         ast_copy_string(subclass, "Stream topology request change", slen);
         break;
      case AST_CONTROL_STREAM_TOPOLOGY_CHANGED:
         ast_copy_string(subclass, "Stream topology changed", slen);
         break;
      case AST_CONTROL_STREAM_TOPOLOGY_SOURCE_CHANGED:
         ast_copy_string(subclass, "Stream topology source changed", slen);
         break;
      case -1:
         ast_copy_string(subclass, "Stop generators", slen);
         break;
      default:
         snprintf(subclass, slen, "Unknown control '%d'", f->subclass.integer);
      }
      break;
   case AST_FRAME_NULL:
      ast_copy_string(subclass, "N/A", slen);
      break;
   case AST_FRAME_IAX:
      /* Should never happen */
      snprintf(subclass, slen, "IAX Frametype %d", f->subclass.integer);
      break;
   case AST_FRAME_BRIDGE_ACTION:
      /* Should never happen */
      snprintf(subclass, slen, "Bridge Frametype %d", f->subclass.integer);
      break;
   case AST_FRAME_BRIDGE_ACTION_SYNC:
      /* Should never happen */
      snprintf(subclass, slen, "Synchronous Bridge Frametype %d", f->subclass.integer);
      break;
   case AST_FRAME_TEXT:
      ast_copy_string(subclass, "N/A", slen);
      if (moreinfo) {
         ast_copy_string(moreinfo, f->data.ptr, mlen);
      }
      break;
   case AST_FRAME_IMAGE:
      snprintf(subclass, slen, "Image format %s\n", ast_format_get_name(f->subclass.format));
      break;
   case AST_FRAME_HTML:
      switch (f->subclass.integer) {
      case AST_HTML_URL:
         ast_copy_string(subclass, "URL", slen);
         if (moreinfo) {
            ast_copy_string(moreinfo, f->data.ptr, mlen);
         }
         break;
      case AST_HTML_DATA:
         ast_copy_string(subclass, "Data", slen);
         break;
      case AST_HTML_BEGIN:
         ast_copy_string(subclass, "Begin", slen);
         break;
      case AST_HTML_END:
         ast_copy_string(subclass, "End", slen);
         break;
      case AST_HTML_LDCOMPLETE:
         ast_copy_string(subclass, "Load Complete", slen);
         break;
      case AST_HTML_NOSUPPORT:
         ast_copy_string(subclass, "No Support", slen);
         break;
      case AST_HTML_LINKURL:
         ast_copy_string(subclass, "Link URL", slen);
         if (moreinfo) {
            ast_copy_string(moreinfo, f->data.ptr, mlen);
         }
         break;
      case AST_HTML_UNLINK:
         ast_copy_string(subclass, "Unlink", slen);
         break;
      case AST_HTML_LINKREJECT:
         ast_copy_string(subclass, "Link Reject", slen);
         break;
      default:
         snprintf(subclass, slen, "Unknown HTML frame '%d'\n", f->subclass.integer);
         break;
      }
      break;
   case AST_FRAME_MODEM:
      switch (f->subclass.integer) {
      case AST_MODEM_T38:
         ast_copy_string(subclass, "T.38", slen);
         break;
      case AST_MODEM_V150:
         ast_copy_string(subclass, "V.150", slen);
         break;
      default:
         snprintf(subclass, slen, "Unknown MODEM frame '%d'\n", f->subclass.integer);
         break;
      }
      break;
   case AST_FRAME_RTCP:
      ast_copy_string(subclass, "RTCP", slen);
   default:
      ast_copy_string(subclass, "Unknown Subclass", slen);
      break;
   }

   return subclass;
}

char *ast_frame_type2str(enum ast_frame_type frame_type, char *ftype, size_t len)
{
   switch (frame_type) {
   case AST_FRAME_DTMF_BEGIN:
      ast_copy_string(ftype, "DTMF Begin", len);
      break;
   case AST_FRAME_DTMF_END:
      ast_copy_string(ftype, "DTMF End", len);
      break;
   case AST_FRAME_CONTROL:
      ast_copy_string(ftype, "Control", len);
      break;
   case AST_FRAME_NULL:
      ast_copy_string(ftype, "Null Frame", len);
      break;
   case AST_FRAME_IAX:
      /* Should never happen */
      ast_copy_string(ftype, "IAX Specific", len);
      break;
   case AST_FRAME_BRIDGE_ACTION:
      /* Should never happen */
      ast_copy_string(ftype, "Bridge Specific", len);
      break;
   case AST_FRAME_BRIDGE_ACTION_SYNC:
      /* Should never happen */
      ast_copy_string(ftype, "Bridge Specific", len);
      break;
   case AST_FRAME_TEXT:
      ast_copy_string(ftype, "Text", len);
      break;
   case AST_FRAME_TEXT_DATA:
      ast_copy_string(ftype, "Text Data", len);
      break;
   case AST_FRAME_IMAGE:
      ast_copy_string(ftype, "Image", len);
      break;
   case AST_FRAME_HTML:
      ast_copy_string(ftype, "HTML", len);
      break;
   case AST_FRAME_MODEM:
      ast_copy_string(ftype, "Modem", len);
      break;
   case AST_FRAME_VOICE:
      ast_copy_string(ftype, "Voice", len);
      break;
   case AST_FRAME_VIDEO:
      ast_copy_string(ftype, "Video", len);
      break;
   case AST_FRAME_RTCP:
      ast_copy_string(ftype, "RTCP", len);
      break;
   default:
      snprintf(ftype, len, "Unknown Frametype '%u'", frame_type);
      break;
   }

   return ftype;
}

/*! Dump a frame for debugging purposes */
void ast_frame_dump(const char *name, struct ast_frame *f, char *prefix)
{
   const char noname[] = "unknown";
   char ftype[40] = "Unknown Frametype";
   char cft[80];
   char subclass[40] = "Unknown Subclass";
   char csub[80];
   char moreinfo[40] = "";
   char cn[60];
   char cp[40];
   char cmn[40];

   if (!name) {
      name = noname;
   }

   if (!f) {
      ast_verb(-1, "%s [ %s (NULL) ] [%s]\n",
         term_color(cp, prefix, COLOR_BRMAGENTA, COLOR_BLACK, sizeof(cp)),
         term_color(cft, "HANGUP", COLOR_BRRED, COLOR_BLACK, sizeof(cft)),
         term_color(cn, name, COLOR_YELLOW, COLOR_BLACK, sizeof(cn)));
      return;
   }
   /* XXX We should probably print one each of voice and video when the format changes XXX */
   if (f->frametype == AST_FRAME_VOICE) {
      return;
   }
   if (f->frametype == AST_FRAME_VIDEO) {
      return;
   }
   if (f->frametype == AST_FRAME_RTCP) {
      return;
   }

   ast_frame_type2str(f->frametype, ftype, sizeof(ftype));
   ast_frame_subclass2str(f, subclass, sizeof(subclass), moreinfo, sizeof(moreinfo));

   if (!ast_strlen_zero(moreinfo))
      ast_verb(-1, "%s [ TYPE: %s (%u) SUBCLASS: %s (%d) '%s' ] [%s]\n",
             term_color(cp, prefix, COLOR_BRMAGENTA, COLOR_BLACK, sizeof(cp)),
             term_color(cft, ftype, COLOR_BRRED, COLOR_BLACK, sizeof(cft)),
             f->frametype,
             term_color(csub, subclass, COLOR_BRCYAN, COLOR_BLACK, sizeof(csub)),
             f->subclass.integer,
             term_color(cmn, moreinfo, COLOR_BRGREEN, COLOR_BLACK, sizeof(cmn)),
             term_color(cn, name, COLOR_YELLOW, COLOR_BLACK, sizeof(cn)));
   else
      ast_verb(-1, "%s [ TYPE: %s (%u) SUBCLASS: %s (%d) ] [%s]\n",
             term_color(cp, prefix, COLOR_BRMAGENTA, COLOR_BLACK, sizeof(cp)),
             term_color(cft, ftype, COLOR_BRRED, COLOR_BLACK, sizeof(cft)),
             f->frametype,
             term_color(csub, subclass, COLOR_BRCYAN, COLOR_BLACK, sizeof(csub)),
             f->subclass.integer,
             term_color(cn, name, COLOR_YELLOW, COLOR_BLACK, sizeof(cn)));
}

int ast_frame_adjust_volume(struct ast_frame *f, int adjustment)
{
   int count;
   short *fdata = f->data.ptr;
   short adjust_value = abs(adjustment);

   if ((f->frametype != AST_FRAME_VOICE) || !(ast_format_cache_is_slinear(f->subclass.format))) {
      return -1;
   }

   if (!adjustment) {
      return 0;
   }

   for (count = 0; count < f->samples; count++) {
      if (adjustment > 0) {
         ast_slinear_saturated_multiply(&fdata[count], &adjust_value);
      } else if (adjustment < 0) {
         ast_slinear_saturated_divide(&fdata[count], &adjust_value);
      }
   }

   return 0;
}

int ast_frame_adjust_volume_float(struct ast_frame *f, float adjustment)
{
   int count;
   short *fdata = f->data.ptr;
   float adjust_value = fabs(adjustment);

   if ((f->frametype != AST_FRAME_VOICE) || !(ast_format_cache_is_slinear(f->subclass.format))) {
      return -1;
   }

   if (!adjustment) {
      return 0;
   }

   for (count = 0; count < f->samples; count++) {
      if (adjustment > 0) {
         ast_slinear_saturated_multiply_float(&fdata[count], &adjust_value);
      } else if (adjustment < 0) {
         ast_slinear_saturated_divide_float(&fdata[count], &adjust_value);
      }
   }

   return 0;
}

int ast_frame_slinear_sum(struct ast_frame *f1, struct ast_frame *f2)
{
   int count;
   short *data1, *data2;

   if ((f1->frametype != AST_FRAME_VOICE) || (ast_format_cmp(f1->subclass.format, ast_format_slin) != AST_FORMAT_CMP_NOT_EQUAL))
      return -1;

   if ((f2->frametype != AST_FRAME_VOICE) || (ast_format_cmp(f2->subclass.format, ast_format_slin) != AST_FORMAT_CMP_NOT_EQUAL))
      return -1;

   if (f1->samples != f2->samples)
      return -1;

   for (count = 0, data1 = f1->data.ptr, data2 = f2->data.ptr;
        count < f1->samples;
        count++, data1++, data2++)
      ast_slinear_saturated_add(data1, data2);

   return 0;
}

int ast_frame_clear(struct ast_frame *frame)
{
   struct ast_frame *next;

   for (next = AST_LIST_NEXT(frame, frame_list);
       frame;
       frame = next, next = frame ? AST_LIST_NEXT(frame, frame_list) : NULL) {
      memset(frame->data.ptr, 0, frame->datalen);
   }
   return 0;
}