frame.c

/*
 * Asterisk -- An open source telephony toolkit.
 *
 * Copyright (C) 1999 - 2005, Digium, Inc.
 *
 * Mark Spencer <markster@digium.com>
 *
 * 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 manipulation routines
 *
 * \author Mark Spencer <markster@digium.com> 
 */

#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <stdio.h>

#include "asterisk.h"

ASTERISK_FILE_VERSION(__FILE__, "$Revision$")

#include "asterisk/lock.h"
#include "asterisk/frame.h"
#include "asterisk/logger.h"
#include "asterisk/options.h"
#include "asterisk/channel.h"
#include "asterisk/cli.h"
#include "asterisk/term.h"
#include "asterisk/utils.h"

#ifdef TRACE_FRAMES
static int headers = 0;
static struct ast_frame *headerlist = NULL;
AST_MUTEX_DEFINE_STATIC(framelock);
#endif

#define SMOOTHER_SIZE 8000

#define TYPE_HIGH	 0x0
#define TYPE_LOW	 0x1
#define TYPE_SILENCE	 0x2
#define TYPE_DONTSEND	 0x3
#define TYPE_MASK	 0x3

struct ast_smoother {
	int size;
	int format;
	int readdata;
	int optimizablestream;
	int flags;
	float samplesperbyte;
	struct ast_frame f;
	struct timeval delivery;
	char data[SMOOTHER_SIZE];
	char framedata[SMOOTHER_SIZE + AST_FRIENDLY_OFFSET];
	struct ast_frame *opt;
	int len;
};

/*! \brief Definition of supported media formats (codecs) */
static struct ast_format_list {
	int visible;	/*!< Can we see this entry */
	int bits;	/*!< bitmask value */
	char *name;	/*!< short name */
	char *desc;	/*!< Description */
} AST_FORMAT_LIST[] = {
	{ 1, AST_FORMAT_G723_1 , "g723" , "G.723.1"},	/*!< codec_g723_1.c */
	{ 1, AST_FORMAT_GSM, "gsm" , "GSM"},		/*!< codec_gsm.c */
	{ 1, AST_FORMAT_ULAW, "ulaw", "G.711 u-law" },	/*!< codec_ulaw.c */
	{ 1, AST_FORMAT_ALAW, "alaw", "G.711 A-law" },	/*!< codec_alaw.c */
	{ 1, AST_FORMAT_G726, "g726", "G.726" },	/*!< codec_g726.c */
	{ 1, AST_FORMAT_ADPCM, "adpcm" , "ADPCM"},	/*!< codec_adpcm.c */
	{ 1, AST_FORMAT_SLINEAR, "slin",  "16 bit Signed Linear PCM"},	/*!<  */
	{ 1, AST_FORMAT_LPC10, "lpc10", "LPC10" },	/*!< codec_lpc10.c */
	{ 1, AST_FORMAT_G729A, "g729", "G.729A" },	/*!< Binary commercial distribution */
	{ 1, AST_FORMAT_SPEEX, "speex", "SpeeX" },	/*!< codec_speex.c */
	{ 1, AST_FORMAT_ILBC, "ilbc", "iLBC"},	/*!< codec_ilbc.c */
	{ 0, 0, "nothing", "undefined" },
	{ 0, 0, "nothing", "undefined" },
	{ 0, 0, "nothing", "undefined" },
	{ 0, 0, "nothing", "undefined" },
	{ 0, AST_FORMAT_MAX_AUDIO, "maxaudio", "Maximum audio format" },
	{ 1, AST_FORMAT_JPEG, "jpeg", "JPEG image"},	/*!< See format_jpeg.c */
	{ 1, AST_FORMAT_PNG, "png", "PNG image"},	/*!< Image format */
	{ 1, AST_FORMAT_H261, "h261", "H.261 Video" },	/*!< Passthrough */
	{ 1, AST_FORMAT_H263, "h263", "H.263 Video" },	/*!< Passthrough support, see format_h263.c */
	{ 1, AST_FORMAT_H263_PLUS, "h263p", "H.263+ Video" },	/*!< See format_h263.c */
	{ 1, AST_FORMAT_H264, "h264", "H.264 Video" },	/*!< Passthrough support, see format_h263.c */
	{ 0, 0, "nothing", "undefined" },
	{ 0, 0, "nothing", "undefined" },
	{ 0, 0, "nothing", "undefined" },
	{ 0, AST_FORMAT_MAX_VIDEO, "maxvideo", "Maximum video format" },
};

struct ast_frame ast_null_frame = { AST_FRAME_NULL, };

void ast_smoother_reset(struct ast_smoother *s, int size)
{
	memset(s, 0, sizeof(struct ast_smoother));
	s->size = size;
}

struct ast_smoother *ast_smoother_new(int size)
{
	struct ast_smoother *s;
	if (size < 1)
		return NULL;
	s = malloc(sizeof(struct ast_smoother));
	if (s)
		ast_smoother_reset(s, size);
	return s;
}

int ast_smoother_get_flags(struct ast_smoother *s)
{
	return s->flags;
}

void ast_smoother_set_flags(struct ast_smoother *s, int flags)
{
	s->flags = flags;
}

int __ast_smoother_feed(struct ast_smoother *s, struct ast_frame *f, int swap)
{
	if (f->frametype != AST_FRAME_VOICE) {
		ast_log(LOG_WARNING, "Huh?  Can't smooth a non-voice frame!\n");
		return -1;
	}
	if (!s->format) {
		s->format = f->subclass;
		s->samplesperbyte = (float)f->samples / (float)f->datalen;
	} else if (s->format != f->subclass) {
		ast_log(LOG_WARNING, "Smoother was working on %d format frames, now trying to feed %d?\n", s->format, f->subclass);
		return -1;
	}
	if (s->len + f->datalen > SMOOTHER_SIZE) {
		ast_log(LOG_WARNING, "Out of smoother space\n");
		return -1;
	}
	if (((f->datalen == s->size) || ((f->datalen < 10) && (s->flags & AST_SMOOTHER_FLAG_G729)))
				 && !s->opt && (f->offset >= AST_MIN_OFFSET)) {
		if (!s->len) {
			/* Optimize by sending the frame we just got
			   on the next read, thus eliminating the douple
			   copy */
			s->opt = f;
			return 0;
		} else {
			s->optimizablestream++;
			if (s->optimizablestream > 10) {
				/* For the past 10 rounds, we have input and output
				   frames of the correct size for this smoother, yet
				   we were unable to optimize because there was still
				   some cruft left over.  Lets just drop the cruft so
				   we can move to a fully optimized path */
				s->len = 0;
				s->opt = f;
				return 0;
			}
		}
	} else 
		s->optimizablestream = 0;
	if (s->flags & AST_SMOOTHER_FLAG_G729) {
		if (s->len % 10) {
			ast_log(LOG_NOTICE, "Dropping extra frame of G.729 since we already have a VAD frame at the end\n");
			return 0;
		}
	}
	if (swap)
		ast_swapcopy_samples(s->data+s->len, f->data, f->samples);
	else
		memcpy(s->data + s->len, f->data, f->datalen);
	/* If either side is empty, reset the delivery time */
	if (!s->len || ast_tvzero(f->delivery) || ast_tvzero(s->delivery))	/* XXX really ? */
		s->delivery = f->delivery;
	s->len += f->datalen;
	return 0;
}

struct ast_frame *ast_smoother_read(struct ast_smoother *s)
{
	struct ast_frame *opt;
	int len;
	/* IF we have an optimization frame, send it */
	if (s->opt) {
		if (s->opt->offset < AST_FRIENDLY_OFFSET)
			ast_log(LOG_WARNING, "Returning a frame of inappropriate offset (%d).",
							s->opt->offset);
		opt = s->opt;
		s->opt = NULL;
		return opt;
	}

	/* Make sure we have enough data */
	if (s->len < s->size) {
		/* Or, if this is a G.729 frame with VAD on it, send it immediately anyway */
		if (!((s->flags & AST_SMOOTHER_FLAG_G729) && (s->size % 10)))
			return NULL;
	}
	len = s->size;
	if (len > s->len)
		len = s->len;
	/* Make frame */
	s->f.frametype = AST_FRAME_VOICE;
	s->f.subclass = s->format;
	s->f.data = s->framedata + AST_FRIENDLY_OFFSET;
	s->f.offset = AST_FRIENDLY_OFFSET;
	s->f.datalen = len;
	/* Samples will be improper given VAD, but with VAD the concept really doesn't even exist */
	s->f.samples = len * s->samplesperbyte;	/* XXX rounding */
	s->f.delivery = s->delivery;
	/* Fill Data */
	memcpy(s->f.data, s->data, len);
	s->len -= len;
	/* Move remaining data to the front if applicable */
	if (s->len) {
		/* In principle this should all be fine because if we are sending
		   G.729 VAD, the next timestamp will take over anyawy */
		memmove(s->data, s->data + len, s->len);
		if (!ast_tvzero(s->delivery)) {
			/* If we have delivery time, increment it, otherwise, leave it at 0 */
			s->delivery = ast_tvadd(s->delivery, ast_samp2tv(s->f.samples, 8000));
		}
	}
	/* Return frame */
	return &s->f;
}

void ast_smoother_free(struct ast_smoother *s)
{
	free(s);
}

static struct ast_frame *ast_frame_header_new(void)
{
	struct ast_frame *f;
	f = malloc(sizeof(struct ast_frame));
	if (f)
		memset(f, 0, sizeof(struct ast_frame));
#ifdef TRACE_FRAMES
	if (f) {
		headers++;
		f->prev = NULL;
		ast_mutex_lock(&framelock);
		f->next = headerlist;
		if (headerlist)
			headerlist->prev = f;
		headerlist = f;
		ast_mutex_unlock(&framelock);
	}
#endif	
	return f;
}

/*!
 * \todo Important: I should be made more efficient.  Frame headers should
 * most definitely be cached
 */
void ast_frfree(struct ast_frame *fr)
{
	if (fr->mallocd & AST_MALLOCD_DATA) {
		if (fr->data) 
			free(fr->data - fr->offset);
	}
	if (fr->mallocd & AST_MALLOCD_SRC) {
		if (fr->src)
			free((char *)fr->src);
	}
	if (fr->mallocd & AST_MALLOCD_HDR) {
#ifdef TRACE_FRAMES
		headers--;
		ast_mutex_lock(&framelock);
		if (fr->next)
			fr->next->prev = fr->prev;
		if (fr->prev)
			fr->prev->next = fr->next;
		else
			headerlist = fr->next;
		ast_mutex_unlock(&framelock);
#endif			
		free(fr);
	}
}

/*!
 * \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)
{
	struct ast_frame *out;
	if (!(fr->mallocd & AST_MALLOCD_HDR)) {
		/* Allocate a new header if needed */
		out = ast_frame_header_new();
		if (!out) {
			ast_log(LOG_WARNING, "Out of memory\n");
			return NULL;
		}
		out->frametype = fr->frametype;
		out->subclass = fr->subclass;
		out->datalen = fr->datalen;
		out->samples = fr->samples;
		out->offset = fr->offset;
		out->src = NULL;
		out->data = fr->data;
	} else {
		out = fr;
	}
	if (!(fr->mallocd & AST_MALLOCD_SRC)) {
		if (fr->src)
			out->src = strdup(fr->src);
	} else
		out->src = fr->src;
	if (!(fr->mallocd & AST_MALLOCD_DATA))  {
		out->data = malloc(fr->datalen + AST_FRIENDLY_OFFSET);
		if (!out->data) {
			free(out);
			ast_log(LOG_WARNING, "Out of memory\n");
			return NULL;
		}
		out->data += AST_FRIENDLY_OFFSET;
		out->offset = AST_FRIENDLY_OFFSET;
		out->datalen = fr->datalen;
		memcpy(out->data, fr->data, fr->datalen);
	}
	out->mallocd = AST_MALLOCD_HDR | AST_MALLOCD_SRC | AST_MALLOCD_DATA;
	return out;
}

struct ast_frame *ast_frdup(struct ast_frame *f)
{
	struct ast_frame *out;
	int len, srclen = 0;
	void *buf;
	/* Start with standard stuff */
	len = sizeof(struct ast_frame) + 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;
	buf = malloc(len);
	if (!buf)
		return NULL;
	out = buf;
	/* Set us as having malloc'd header only, so it will eventually
	   get freed. */
	out->frametype = f->frametype;
	out->subclass = f->subclass;
	out->datalen = f->datalen;
	out->samples = f->samples;
	out->delivery = f->delivery;
	out->mallocd = AST_MALLOCD_HDR;
	out->offset = AST_FRIENDLY_OFFSET;
	out->data = buf + sizeof(struct ast_frame) + AST_FRIENDLY_OFFSET;
	if (srclen > 0) {
		out->src = out->data + f->datalen;
		/* Must have space since we allocated for it */
		strcpy((char *)out->src, f->src);
	} else
		out->src = NULL;
	out->prev = NULL;
	out->next = NULL;
	memcpy(out->data, f->data, out->datalen);	
	return out;
}

#if 0
/*
 * XXX
 * This function is badly broken - it does not handle correctly
 * partial reads on either header or body.
 * However is it never used anywhere so we leave it commented out
 */
struct ast_frame *ast_fr_fdread(int fd)
{
	char buf[65536];
	int res;
	int ttl = sizeof(struct ast_frame);
	struct ast_frame *f = (struct ast_frame *)buf;
	/* Read a frame directly from there.  They're always in the
	   right format. */
	
	while(ttl) {
		res = read(fd, buf, ttl);
		if (res < 0) {
			ast_log(LOG_WARNING, "Bad read on %d: %s\n", fd, strerror(errno));
			return NULL;
		}
		ttl -= res;
	}
	
	/* read the frame header */
	f->mallocd = 0;
	/* Re-write data position */
	f->data = buf + sizeof(struct ast_frame);
	f->offset = 0;
	/* Forget about being mallocd */
	f->mallocd = 0;
	/* Re-write the source */
	f->src = (char *)__FUNCTION__;
	if (f->datalen > sizeof(buf) - sizeof(struct ast_frame)) {
		/* Really bad read */
		ast_log(LOG_WARNING, "Strange read (%d bytes)\n", f->datalen);
		return NULL;
	}
	if (f->datalen) {
		if ((res = read(fd, f->data, f->datalen)) != f->datalen) {
			/* Bad read */
			ast_log(LOG_WARNING, "How very strange, expected %d, got %d\n", f->datalen, res);
			return NULL;
		}
	}
	if ((f->frametype == AST_FRAME_CONTROL) && (f->subclass == AST_CONTROL_HANGUP)) {
		return NULL;
	}
	return ast_frisolate(f);
}

/* Some convenient routines for sending frames to/from stream or datagram
   sockets, pipes, etc (maybe even files) */

/*
 * XXX this function is also partly broken because it does not handle
 * partial writes. We comment it out too, and also the unique
 * client it has, ast_fr_fdhangup()
 */
int ast_fr_fdwrite(int fd, struct ast_frame *frame)
{
	/* Write the frame exactly */
	if (write(fd, frame, sizeof(struct ast_frame)) != sizeof(struct ast_frame)) {
		ast_log(LOG_WARNING, "Write error: %s\n", strerror(errno));