cannam@85: /*
cannam@85:  * libmad - MPEG audio decoder library
cannam@85:  * Copyright (C) 2000-2004 Underbit Technologies, Inc.
cannam@85:  *
cannam@85:  * This program is free software; you can redistribute it and/or modify
cannam@85:  * it under the terms of the GNU General Public License as published by
cannam@85:  * the Free Software Foundation; either version 2 of the License, or
cannam@85:  * (at your option) any later version.
cannam@85:  *
cannam@85:  * This program is distributed in the hope that it will be useful,
cannam@85:  * but WITHOUT ANY WARRANTY; without even the implied warranty of
cannam@85:  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
cannam@85:  * GNU General Public License for more details.
cannam@85:  *
cannam@85:  * You should have received a copy of the GNU General Public License
cannam@85:  * along with this program; if not, write to the Free Software
cannam@85:  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
cannam@85:  *
cannam@85:  * $Id: decoder.c,v 1.22 2004/01/23 09:41:32 rob Exp $
cannam@85:  */
cannam@85: 
cannam@85: # ifdef HAVE_CONFIG_H
cannam@85: #  include "config.h"
cannam@85: # endif
cannam@85: 
cannam@85: # include "global.h"
cannam@85: 
cannam@85: # ifdef HAVE_SYS_TYPES_H
cannam@85: #  include <sys/types.h>
cannam@85: # endif
cannam@85: 
cannam@85: # ifdef HAVE_SYS_WAIT_H
cannam@85: #  include <sys/wait.h>
cannam@85: # endif
cannam@85: 
cannam@85: # ifdef HAVE_UNISTD_H
cannam@85: #  include <unistd.h>
cannam@85: # endif
cannam@85: 
cannam@85: # ifdef HAVE_FCNTL_H
cannam@85: #  include <fcntl.h>
cannam@85: # endif
cannam@85: 
cannam@85: # include <stdlib.h>
cannam@85: 
cannam@85: # ifdef HAVE_ERRNO_H
cannam@85: #  include <errno.h>
cannam@85: # endif
cannam@85: 
cannam@85: # include "stream.h"
cannam@85: # include "frame.h"
cannam@85: # include "synth.h"
cannam@85: # include "decoder.h"
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	decoder->init()
cannam@85:  * DESCRIPTION:	initialize a decoder object with callback routines
cannam@85:  */
cannam@85: void mad_decoder_init(struct mad_decoder *decoder, void *data,
cannam@85: 		      enum mad_flow (*input_func)(void *,
cannam@85: 						  struct mad_stream *),
cannam@85: 		      enum mad_flow (*header_func)(void *,
cannam@85: 						   struct mad_header const *),
cannam@85: 		      enum mad_flow (*filter_func)(void *,
cannam@85: 						   struct mad_stream const *,
cannam@85: 						   struct mad_frame *),
cannam@85: 		      enum mad_flow (*output_func)(void *,
cannam@85: 						   struct mad_header const *,
cannam@85: 						   struct mad_pcm *),
cannam@85: 		      enum mad_flow (*error_func)(void *,
cannam@85: 						  struct mad_stream *,
cannam@85: 						  struct mad_frame *),
cannam@85: 		      enum mad_flow (*message_func)(void *,
cannam@85: 						    void *, unsigned int *))
cannam@85: {
cannam@85:   decoder->mode         = -1;
cannam@85: 
cannam@85:   decoder->options      = 0;
cannam@85: 
cannam@85:   decoder->async.pid    = 0;
cannam@85:   decoder->async.in     = -1;
cannam@85:   decoder->async.out    = -1;
cannam@85: 
cannam@85:   decoder->sync         = 0;
cannam@85: 
cannam@85:   decoder->cb_data      = data;
cannam@85: 
cannam@85:   decoder->input_func   = input_func;
cannam@85:   decoder->header_func  = header_func;
cannam@85:   decoder->filter_func  = filter_func;
cannam@85:   decoder->output_func  = output_func;
cannam@85:   decoder->error_func   = error_func;
cannam@85:   decoder->message_func = message_func;
cannam@85: }
cannam@85: 
cannam@85: int mad_decoder_finish(struct mad_decoder *decoder)
cannam@85: {
cannam@85: # if defined(USE_ASYNC)
cannam@85:   if (decoder->mode == MAD_DECODER_MODE_ASYNC && decoder->async.pid) {
cannam@85:     pid_t pid;
cannam@85:     int status;
cannam@85: 
cannam@85:     close(decoder->async.in);
cannam@85: 
cannam@85:     do
cannam@85:       pid = waitpid(decoder->async.pid, &status, 0);
cannam@85:     while (pid == -1 && errno == EINTR);
cannam@85: 
cannam@85:     decoder->mode = -1;
cannam@85: 
cannam@85:     close(decoder->async.out);
cannam@85: 
cannam@85:     decoder->async.pid = 0;
cannam@85:     decoder->async.in  = -1;
cannam@85:     decoder->async.out = -1;
cannam@85: 
cannam@85:     if (pid == -1)
cannam@85:       return -1;
cannam@85: 
cannam@85:     return (!WIFEXITED(status) || WEXITSTATUS(status)) ? -1 : 0;
cannam@85:   }
cannam@85: # endif
cannam@85: 
cannam@85:   return 0;
cannam@85: }
cannam@85: 
cannam@85: # if defined(USE_ASYNC)
cannam@85: static
cannam@85: enum mad_flow send_io(int fd, void const *data, size_t len)
cannam@85: {
cannam@85:   char const *ptr = data;
cannam@85:   ssize_t count;
cannam@85: 
cannam@85:   while (len) {
cannam@85:     do
cannam@85:       count = write(fd, ptr, len);
cannam@85:     while (count == -1 && errno == EINTR);
cannam@85: 
cannam@85:     if (count == -1)
cannam@85:       return MAD_FLOW_BREAK;
cannam@85: 
cannam@85:     len -= count;
cannam@85:     ptr += count;
cannam@85:   }
cannam@85: 
cannam@85:   return MAD_FLOW_CONTINUE;
cannam@85: }
cannam@85: 
cannam@85: static
cannam@85: enum mad_flow receive_io(int fd, void *buffer, size_t len)
cannam@85: {
cannam@85:   char *ptr = buffer;
cannam@85:   ssize_t count;
cannam@85: 
cannam@85:   while (len) {
cannam@85:     do
cannam@85:       count = read(fd, ptr, len);
cannam@85:     while (count == -1 && errno == EINTR);
cannam@85: 
cannam@85:     if (count == -1)
cannam@85:       return (errno == EAGAIN) ? MAD_FLOW_IGNORE : MAD_FLOW_BREAK;
cannam@85:     else if (count == 0)
cannam@85:       return MAD_FLOW_STOP;
cannam@85: 
cannam@85:     len -= count;
cannam@85:     ptr += count;
cannam@85:   }
cannam@85: 
cannam@85:   return MAD_FLOW_CONTINUE;
cannam@85: }
cannam@85: 
cannam@85: static
cannam@85: enum mad_flow receive_io_blocking(int fd, void *buffer, size_t len)
cannam@85: {
cannam@85:   int flags, blocking;
cannam@85:   enum mad_flow result;
cannam@85: 
cannam@85:   flags = fcntl(fd, F_GETFL);
cannam@85:   if (flags == -1)
cannam@85:     return MAD_FLOW_BREAK;
cannam@85: 
cannam@85:   blocking = flags & ~O_NONBLOCK;
cannam@85: 
cannam@85:   if (blocking != flags &&
cannam@85:       fcntl(fd, F_SETFL, blocking) == -1)
cannam@85:     return MAD_FLOW_BREAK;
cannam@85: 
cannam@85:   result = receive_io(fd, buffer, len);
cannam@85: 
cannam@85:   if (flags != blocking &&
cannam@85:       fcntl(fd, F_SETFL, flags) == -1)
cannam@85:     return MAD_FLOW_BREAK;
cannam@85: 
cannam@85:   return result;
cannam@85: }
cannam@85: 
cannam@85: static
cannam@85: enum mad_flow send(int fd, void const *message, unsigned int size)
cannam@85: {
cannam@85:   enum mad_flow result;
cannam@85: 
cannam@85:   /* send size */
cannam@85: 
cannam@85:   result = send_io(fd, &size, sizeof(size));
cannam@85: 
cannam@85:   /* send message */
cannam@85: 
cannam@85:   if (result == MAD_FLOW_CONTINUE)
cannam@85:     result = send_io(fd, message, size);
cannam@85: 
cannam@85:   return result;
cannam@85: }
cannam@85: 
cannam@85: static
cannam@85: enum mad_flow receive(int fd, void **message, unsigned int *size)
cannam@85: {
cannam@85:   enum mad_flow result;
cannam@85:   unsigned int actual;
cannam@85: 
cannam@85:   if (*message == 0)
cannam@85:     *size = 0;
cannam@85: 
cannam@85:   /* receive size */
cannam@85: 
cannam@85:   result = receive_io(fd, &actual, sizeof(actual));
cannam@85: 
cannam@85:   /* receive message */
cannam@85: 
cannam@85:   if (result == MAD_FLOW_CONTINUE) {
cannam@85:     if (actual > *size)
cannam@85:       actual -= *size;
cannam@85:     else {
cannam@85:       *size  = actual;
cannam@85:       actual = 0;
cannam@85:     }
cannam@85: 
cannam@85:     if (*size > 0) {
cannam@85:       if (*message == 0) {
cannam@85: 	*message = malloc(*size);
cannam@85: 	if (*message == 0)
cannam@85: 	  return MAD_FLOW_BREAK;
cannam@85:       }
cannam@85: 
cannam@85:       result = receive_io_blocking(fd, *message, *size);
cannam@85:     }
cannam@85: 
cannam@85:     /* throw away remainder of message */
cannam@85: 
cannam@85:     while (actual && result == MAD_FLOW_CONTINUE) {
cannam@85:       char sink[256];
cannam@85:       unsigned int len;
cannam@85: 
cannam@85:       len = actual > sizeof(sink) ? sizeof(sink) : actual;
cannam@85: 
cannam@85:       result = receive_io_blocking(fd, sink, len);
cannam@85: 
cannam@85:       actual -= len;
cannam@85:     }
cannam@85:   }
cannam@85: 
cannam@85:   return result;
cannam@85: }
cannam@85: 
cannam@85: static
cannam@85: enum mad_flow check_message(struct mad_decoder *decoder)
cannam@85: {
cannam@85:   enum mad_flow result;
cannam@85:   void *message = 0;
cannam@85:   unsigned int size;
cannam@85: 
cannam@85:   result = receive(decoder->async.in, &message, &size);
cannam@85: 
cannam@85:   if (result == MAD_FLOW_CONTINUE) {
cannam@85:     if (decoder->message_func == 0)
cannam@85:       size = 0;
cannam@85:     else {
cannam@85:       result = decoder->message_func(decoder->cb_data, message, &size);
cannam@85: 
cannam@85:       if (result == MAD_FLOW_IGNORE ||
cannam@85: 	  result == MAD_FLOW_BREAK)
cannam@85: 	size = 0;
cannam@85:     }
cannam@85: 
cannam@85:     if (send(decoder->async.out, message, size) != MAD_FLOW_CONTINUE)
cannam@85:       result = MAD_FLOW_BREAK;
cannam@85:   }
cannam@85: 
cannam@85:   if (message)
cannam@85:     free(message);
cannam@85: 
cannam@85:   return result;
cannam@85: }
cannam@85: # endif
cannam@85: 
cannam@85: static
cannam@85: enum mad_flow error_default(void *data, struct mad_stream *stream,
cannam@85: 			    struct mad_frame *frame)
cannam@85: {
cannam@85:   int *bad_last_frame = data;
cannam@85: 
cannam@85:   switch (stream->error) {
cannam@85:   case MAD_ERROR_BADCRC:
cannam@85:     if (*bad_last_frame)
cannam@85:       mad_frame_mute(frame);
cannam@85:     else
cannam@85:       *bad_last_frame = 1;
cannam@85: 
cannam@85:     return MAD_FLOW_IGNORE;
cannam@85: 
cannam@85:   default:
cannam@85:     return MAD_FLOW_CONTINUE;
cannam@85:   }
cannam@85: }
cannam@85: 
cannam@85: static
cannam@85: int run_sync(struct mad_decoder *decoder)
cannam@85: {
cannam@85:   enum mad_flow (*error_func)(void *, struct mad_stream *, struct mad_frame *);
cannam@85:   void *error_data;
cannam@85:   int bad_last_frame = 0;
cannam@85:   struct mad_stream *stream;
cannam@85:   struct mad_frame *frame;
cannam@85:   struct mad_synth *synth;
cannam@85:   int result = 0;
cannam@85: 
cannam@85:   if (decoder->input_func == 0)
cannam@85:     return 0;
cannam@85: 
cannam@85:   if (decoder->error_func) {
cannam@85:     error_func = decoder->error_func;
cannam@85:     error_data = decoder->cb_data;
cannam@85:   }
cannam@85:   else {
cannam@85:     error_func = error_default;
cannam@85:     error_data = &bad_last_frame;
cannam@85:   }
cannam@85: 
cannam@85:   stream = &decoder->sync->stream;
cannam@85:   frame  = &decoder->sync->frame;
cannam@85:   synth  = &decoder->sync->synth;
cannam@85: 
cannam@85:   mad_stream_init(stream);
cannam@85:   mad_frame_init(frame);
cannam@85:   mad_synth_init(synth);
cannam@85: 
cannam@85:   mad_stream_options(stream, decoder->options);
cannam@85: 
cannam@85:   do {
cannam@85:     switch (decoder->input_func(decoder->cb_data, stream)) {
cannam@85:     case MAD_FLOW_STOP:
cannam@85:       goto done;
cannam@85:     case MAD_FLOW_BREAK:
cannam@85:       goto fail;
cannam@85:     case MAD_FLOW_IGNORE:
cannam@85:       continue;
cannam@85:     case MAD_FLOW_CONTINUE:
cannam@85:       break;
cannam@85:     }
cannam@85: 
cannam@85:     while (1) {
cannam@85: # if defined(USE_ASYNC)
cannam@85:       if (decoder->mode == MAD_DECODER_MODE_ASYNC) {
cannam@85: 	switch (check_message(decoder)) {
cannam@85: 	case MAD_FLOW_IGNORE:
cannam@85: 	case MAD_FLOW_CONTINUE:
cannam@85: 	  break;
cannam@85: 	case MAD_FLOW_BREAK:
cannam@85: 	  goto fail;
cannam@85: 	case MAD_FLOW_STOP:
cannam@85: 	  goto done;
cannam@85: 	}
cannam@85:       }
cannam@85: # endif
cannam@85: 
cannam@85:       if (decoder->header_func) {
cannam@85: 	if (mad_header_decode(&frame->header, stream) == -1) {
cannam@85: 	  if (!MAD_RECOVERABLE(stream->error))
cannam@85: 	    break;
cannam@85: 
cannam@85: 	  switch (error_func(error_data, stream, frame)) {
cannam@85: 	  case MAD_FLOW_STOP:
cannam@85: 	    goto done;
cannam@85: 	  case MAD_FLOW_BREAK:
cannam@85: 	    goto fail;
cannam@85: 	  case MAD_FLOW_IGNORE:
cannam@85: 	  case MAD_FLOW_CONTINUE:
cannam@85: 	  default:
cannam@85: 	    continue;
cannam@85: 	  }
cannam@85: 	}
cannam@85: 
cannam@85: 	switch (decoder->header_func(decoder->cb_data, &frame->header)) {
cannam@85: 	case MAD_FLOW_STOP:
cannam@85: 	  goto done;
cannam@85: 	case MAD_FLOW_BREAK:
cannam@85: 	  goto fail;
cannam@85: 	case MAD_FLOW_IGNORE:
cannam@85: 	  continue;
cannam@85: 	case MAD_FLOW_CONTINUE:
cannam@85: 	  break;
cannam@85: 	}
cannam@85:       }
cannam@85: 
cannam@85:       if (mad_frame_decode(frame, stream) == -1) {
cannam@85: 	if (!MAD_RECOVERABLE(stream->error))
cannam@85: 	  break;
cannam@85: 
cannam@85: 	switch (error_func(error_data, stream, frame)) {
cannam@85: 	case MAD_FLOW_STOP:
cannam@85: 	  goto done;
cannam@85: 	case MAD_FLOW_BREAK:
cannam@85: 	  goto fail;
cannam@85: 	case MAD_FLOW_IGNORE:
cannam@85: 	  break;
cannam@85: 	case MAD_FLOW_CONTINUE:
cannam@85: 	default:
cannam@85: 	  continue;
cannam@85: 	}
cannam@85:       }
cannam@85:       else
cannam@85: 	bad_last_frame = 0;
cannam@85: 
cannam@85:       if (decoder->filter_func) {
cannam@85: 	switch (decoder->filter_func(decoder->cb_data, stream, frame)) {
cannam@85: 	case MAD_FLOW_STOP:
cannam@85: 	  goto done;
cannam@85: 	case MAD_FLOW_BREAK:
cannam@85: 	  goto fail;
cannam@85: 	case MAD_FLOW_IGNORE:
cannam@85: 	  continue;
cannam@85: 	case MAD_FLOW_CONTINUE:
cannam@85: 	  break;
cannam@85: 	}
cannam@85:       }
cannam@85: 
cannam@85:       mad_synth_frame(synth, frame);
cannam@85: 
cannam@85:       if (decoder->output_func) {
cannam@85: 	switch (decoder->output_func(decoder->cb_data,
cannam@85: 				     &frame->header, &synth->pcm)) {
cannam@85: 	case MAD_FLOW_STOP:
cannam@85: 	  goto done;
cannam@85: 	case MAD_FLOW_BREAK:
cannam@85: 	  goto fail;
cannam@85: 	case MAD_FLOW_IGNORE:
cannam@85: 	case MAD_FLOW_CONTINUE:
cannam@85: 	  break;
cannam@85: 	}
cannam@85:       }
cannam@85:     }
cannam@85:   }
cannam@85:   while (stream->error == MAD_ERROR_BUFLEN);
cannam@85: 
cannam@85:  fail:
cannam@85:   result = -1;
cannam@85: 
cannam@85:  done:
cannam@85:   mad_synth_finish(synth);
cannam@85:   mad_frame_finish(frame);
cannam@85:   mad_stream_finish(stream);
cannam@85: 
cannam@85:   return result;
cannam@85: }
cannam@85: 
cannam@85: # if defined(USE_ASYNC)
cannam@85: static
cannam@85: int run_async(struct mad_decoder *decoder)
cannam@85: {
cannam@85:   pid_t pid;
cannam@85:   int ptoc[2], ctop[2], flags;
cannam@85: 
cannam@85:   if (pipe(ptoc) == -1)
cannam@85:     return -1;
cannam@85: 
cannam@85:   if (pipe(ctop) == -1) {
cannam@85:     close(ptoc[0]);
cannam@85:     close(ptoc[1]);
cannam@85:     return -1;
cannam@85:   }
cannam@85: 
cannam@85:   flags = fcntl(ptoc[0], F_GETFL);
cannam@85:   if (flags == -1 ||
cannam@85:       fcntl(ptoc[0], F_SETFL, flags | O_NONBLOCK) == -1) {
cannam@85:     close(ctop[0]);
cannam@85:     close(ctop[1]);
cannam@85:     close(ptoc[0]);
cannam@85:     close(ptoc[1]);
cannam@85:     return -1;
cannam@85:   }
cannam@85: 
cannam@85:   pid = fork();
cannam@85:   if (pid == -1) {
cannam@85:     close(ctop[0]);
cannam@85:     close(ctop[1]);
cannam@85:     close(ptoc[0]);
cannam@85:     close(ptoc[1]);
cannam@85:     return -1;
cannam@85:   }
cannam@85: 
cannam@85:   decoder->async.pid = pid;
cannam@85: 
cannam@85:   if (pid) {
cannam@85:     /* parent */
cannam@85: 
cannam@85:     close(ptoc[0]);
cannam@85:     close(ctop[1]);
cannam@85: 
cannam@85:     decoder->async.in  = ctop[0];
cannam@85:     decoder->async.out = ptoc[1];
cannam@85: 
cannam@85:     return 0;
cannam@85:   }
cannam@85: 
cannam@85:   /* child */
cannam@85: 
cannam@85:   close(ptoc[1]);
cannam@85:   close(ctop[0]);
cannam@85: 
cannam@85:   decoder->async.in  = ptoc[0];
cannam@85:   decoder->async.out = ctop[1];
cannam@85: 
cannam@85:   _exit(run_sync(decoder));
cannam@85: 
cannam@85:   /* not reached */
cannam@85:   return -1;
cannam@85: }
cannam@85: # endif
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	decoder->run()
cannam@85:  * DESCRIPTION:	run the decoder thread either synchronously or asynchronously
cannam@85:  */
cannam@85: int mad_decoder_run(struct mad_decoder *decoder, enum mad_decoder_mode mode)
cannam@85: {
cannam@85:   int result;
cannam@85:   int (*run)(struct mad_decoder *) = 0;
cannam@85: 
cannam@85:   switch (decoder->mode = mode) {
cannam@85:   case MAD_DECODER_MODE_SYNC:
cannam@85:     run = run_sync;
cannam@85:     break;
cannam@85: 
cannam@85:   case MAD_DECODER_MODE_ASYNC:
cannam@85: # if defined(USE_ASYNC)
cannam@85:     run = run_async;
cannam@85: # endif
cannam@85:     break;
cannam@85:   }
cannam@85: 
cannam@85:   if (run == 0)
cannam@85:     return -1;
cannam@85: 
cannam@85:   decoder->sync = malloc(sizeof(*decoder->sync));
cannam@85:   if (decoder->sync == 0)
cannam@85:     return -1;
cannam@85: 
cannam@85:   result = run(decoder);
cannam@85: 
cannam@85:   free(decoder->sync);
cannam@85:   decoder->sync = 0;
cannam@85: 
cannam@85:   return result;
cannam@85: }
cannam@85: 
cannam@85: /*
cannam@85:  * NAME:	decoder->message()
cannam@85:  * DESCRIPTION:	send a message to and receive a reply from the decoder process
cannam@85:  */
cannam@85: int mad_decoder_message(struct mad_decoder *decoder,
cannam@85: 			void *message, unsigned int *len)
cannam@85: {
cannam@85: # if defined(USE_ASYNC)
cannam@85:   if (decoder->mode != MAD_DECODER_MODE_ASYNC ||
cannam@85:       send(decoder->async.out, message, *len) != MAD_FLOW_CONTINUE ||
cannam@85:       receive(decoder->async.in, &message, len) != MAD_FLOW_CONTINUE)
cannam@85:     return -1;
cannam@85: 
cannam@85:   return 0;
cannam@85: # else
cannam@85:   return -1;
cannam@85: # endif
cannam@85: }