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;
}