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-rw-r--r--libmad/src/decoder.c582
1 files changed, 582 insertions, 0 deletions
diff --git a/libmad/src/decoder.c b/libmad/src/decoder.c
new file mode 100644
index 0000000..6d6df0d
--- /dev/null
+++ b/libmad/src/decoder.c
@@ -0,0 +1,582 @@
+/*
+ * libmad - MPEG audio decoder library
+ * Copyright (C) 2000-2004 Underbit Technologies, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ * $Id: decoder.c,v 1.22 2004/01/23 09:41:32 rob Exp $
+ */
+
+# ifdef HAVE_CONFIG_H
+# include "config.h"
+# endif
+
+# include "global.h"
+
+# ifdef HAVE_SYS_TYPES_H
+# include <sys/types.h>
+# endif
+
+# ifdef HAVE_SYS_WAIT_H
+# include <sys/wait.h>
+# endif
+
+# ifdef HAVE_UNISTD_H
+# include <unistd.h>
+# endif
+
+# ifdef HAVE_FCNTL_H
+# include <fcntl.h>
+# endif
+
+# include <stdlib.h>
+
+# ifdef HAVE_ERRNO_H
+# include <errno.h>
+# endif
+
+# include "stream.h"
+# include "frame.h"
+# include "synth.h"
+# include "decoder.h"
+
+/*
+ * NAME: decoder->init()
+ * DESCRIPTION: initialize a decoder object with callback routines
+ */
+void mad_decoder_init(struct mad_decoder *decoder, void *data,
+ enum mad_flow (*input_func)(void *,
+ struct mad_stream *),
+ enum mad_flow (*header_func)(void *,
+ struct mad_header const *),
+ enum mad_flow (*filter_func)(void *,
+ struct mad_stream const *,
+ struct mad_frame *),
+ enum mad_flow (*output_func)(void *,
+ struct mad_header const *,
+ struct mad_pcm *),
+ enum mad_flow (*error_func)(void *,
+ struct mad_stream *,
+ struct mad_frame *),
+ enum mad_flow (*message_func)(void *,
+ void *, unsigned int *))
+{
+ decoder->mode = -1;
+
+ decoder->options = 0;
+
+ decoder->async.pid = 0;
+ decoder->async.in = -1;
+ decoder->async.out = -1;
+
+ decoder->sync = 0;
+
+ decoder->cb_data = data;
+
+ decoder->input_func = input_func;
+ decoder->header_func = header_func;
+ decoder->filter_func = filter_func;
+ decoder->output_func = output_func;
+ decoder->error_func = error_func;
+ decoder->message_func = message_func;
+}
+
+int mad_decoder_finish(struct mad_decoder *decoder)
+{
+# if defined(USE_ASYNC)
+ if (decoder->mode == MAD_DECODER_MODE_ASYNC && decoder->async.pid) {
+ pid_t pid;
+ int status;
+
+ close(decoder->async.in);
+
+ do
+ pid = waitpid(decoder->async.pid, &status, 0);
+ while (pid == -1 && errno == EINTR);
+
+ decoder->mode = -1;
+
+ close(decoder->async.out);
+
+ decoder->async.pid = 0;
+ decoder->async.in = -1;
+ decoder->async.out = -1;
+
+ if (pid == -1)
+ return -1;
+
+ return (!WIFEXITED(status) || WEXITSTATUS(status)) ? -1 : 0;
+ }
+# endif
+
+ return 0;
+}
+
+# if defined(USE_ASYNC)
+static
+enum mad_flow send_io(int fd, void const *data, size_t len)
+{
+ char const *ptr = data;
+ ssize_t count;
+
+ while (len) {
+ do
+ count = write(fd, ptr, len);
+ while (count == -1 && errno == EINTR);
+
+ if (count == -1)
+ return MAD_FLOW_BREAK;
+
+ len -= count;
+ ptr += count;
+ }
+
+ return MAD_FLOW_CONTINUE;
+}
+
+static
+enum mad_flow receive_io(int fd, void *buffer, size_t len)
+{
+ char *ptr = buffer;
+ ssize_t count;
+
+ while (len) {
+ do
+ count = read(fd, ptr, len);
+ while (count == -1 && errno == EINTR);
+
+ if (count == -1)
+ return (errno == EAGAIN) ? MAD_FLOW_IGNORE : MAD_FLOW_BREAK;
+ else if (count == 0)
+ return MAD_FLOW_STOP;
+
+ len -= count;
+ ptr += count;
+ }
+
+ return MAD_FLOW_CONTINUE;
+}
+
+static
+enum mad_flow receive_io_blocking(int fd, void *buffer, size_t len)
+{
+ int flags, blocking;
+ enum mad_flow result;
+
+ flags = fcntl(fd, F_GETFL);
+ if (flags == -1)
+ return MAD_FLOW_BREAK;
+
+ blocking = flags & ~O_NONBLOCK;
+
+ if (blocking != flags &&
+ fcntl(fd, F_SETFL, blocking) == -1)
+ return MAD_FLOW_BREAK;
+
+ result = receive_io(fd, buffer, len);
+
+ if (flags != blocking &&
+ fcntl(fd, F_SETFL, flags) == -1)
+ return MAD_FLOW_BREAK;
+
+ return result;
+}
+
+static
+enum mad_flow send(int fd, void const *message, unsigned int size)
+{
+ enum mad_flow result;
+
+ /* send size */
+
+ result = send_io(fd, &size, sizeof(size));
+
+ /* send message */
+
+ if (result == MAD_FLOW_CONTINUE)
+ result = send_io(fd, message, size);
+
+ return result;
+}
+
+static
+enum mad_flow receive(int fd, void **message, unsigned int *size)
+{
+ enum mad_flow result;
+ unsigned int actual;
+
+ if (*message == 0)
+ *size = 0;
+
+ /* receive size */
+
+ result = receive_io(fd, &actual, sizeof(actual));
+
+ /* receive message */
+
+ if (result == MAD_FLOW_CONTINUE) {
+ if (actual > *size)
+ actual -= *size;
+ else {
+ *size = actual;
+ actual = 0;
+ }
+
+ if (*size > 0) {
+ if (*message == 0) {
+ *message = malloc(*size);
+ if (*message == 0)
+ return MAD_FLOW_BREAK;
+ }
+
+ result = receive_io_blocking(fd, *message, *size);
+ }
+
+ /* throw away remainder of message */
+
+ while (actual && result == MAD_FLOW_CONTINUE) {
+ char sink[256];
+ unsigned int len;
+
+ len = actual > sizeof(sink) ? sizeof(sink) : actual;
+
+ result = receive_io_blocking(fd, sink, len);
+
+ actual -= len;
+ }
+ }
+
+ return result;
+}
+
+static
+enum mad_flow check_message(struct mad_decoder *decoder)
+{
+ enum mad_flow result;
+ void *message = 0;
+ unsigned int size;
+
+ result = receive(decoder->async.in, &message, &size);
+
+ if (result == MAD_FLOW_CONTINUE) {
+ if (decoder->message_func == 0)
+ size = 0;
+ else {
+ result = decoder->message_func(decoder->cb_data, message, &size);
+
+ if (result == MAD_FLOW_IGNORE ||
+ result == MAD_FLOW_BREAK)
+ size = 0;
+ }
+
+ if (send(decoder->async.out, message, size) != MAD_FLOW_CONTINUE)
+ result = MAD_FLOW_BREAK;
+ }
+
+ if (message)
+ free(message);
+
+ return result;
+}
+# endif
+
+static
+enum mad_flow error_default(void *data, struct mad_stream *stream,
+ struct mad_frame *frame)
+{
+ int *bad_last_frame = data;
+
+ switch (stream->error) {
+ case MAD_ERROR_BADCRC:
+ if (*bad_last_frame)
+ mad_frame_mute(frame);
+ else
+ *bad_last_frame = 1;
+
+ return MAD_FLOW_IGNORE;
+
+ default:
+ return MAD_FLOW_CONTINUE;
+ }
+}
+
+static
+int run_sync(struct mad_decoder *decoder)
+{
+ enum mad_flow (*error_func)(void *, struct mad_stream *, struct mad_frame *);
+ void *error_data;
+ int bad_last_frame = 0;
+ struct mad_stream *stream;
+ struct mad_frame *frame;
+ struct mad_synth *synth;
+ int result = 0;
+
+ if (decoder->input_func == 0)
+ return 0;
+
+ if (decoder->error_func) {
+ error_func = decoder->error_func;
+ error_data = decoder->cb_data;
+ }
+ else {
+ error_func = error_default;
+ error_data = &bad_last_frame;
+ }
+
+ stream = &decoder->sync->stream;
+ frame = &decoder->sync->frame;
+ synth = &decoder->sync->synth;
+
+ mad_stream_init(stream);
+ mad_frame_init(frame);
+ mad_synth_init(synth);
+
+ mad_stream_options(stream, decoder->options);
+
+ do {
+ switch (decoder->input_func(decoder->cb_data, stream)) {
+ case MAD_FLOW_STOP:
+ goto done;
+ case MAD_FLOW_BREAK:
+ goto fail;
+ case MAD_FLOW_IGNORE:
+ continue;
+ case MAD_FLOW_CONTINUE:
+ break;
+ }
+
+ while (1) {
+# if defined(USE_ASYNC)
+ if (decoder->mode == MAD_DECODER_MODE_ASYNC) {
+ switch (check_message(decoder)) {
+ case MAD_FLOW_IGNORE:
+ case MAD_FLOW_CONTINUE:
+ break;
+ case MAD_FLOW_BREAK:
+ goto fail;
+ case MAD_FLOW_STOP:
+ goto done;
+ }
+ }
+# endif
+
+ if (decoder->header_func) {
+ if (mad_header_decode(&frame->header, stream) == -1) {
+ if (!MAD_RECOVERABLE(stream->error))
+ break;
+
+ switch (error_func(error_data, stream, frame)) {
+ case MAD_FLOW_STOP:
+ goto done;
+ case MAD_FLOW_BREAK:
+ goto fail;
+ case MAD_FLOW_IGNORE:
+ case MAD_FLOW_CONTINUE:
+ default:
+ continue;
+ }
+ }
+
+ switch (decoder->header_func(decoder->cb_data, &frame->header)) {
+ case MAD_FLOW_STOP:
+ goto done;
+ case MAD_FLOW_BREAK:
+ goto fail;
+ case MAD_FLOW_IGNORE:
+ continue;
+ case MAD_FLOW_CONTINUE:
+ break;
+ }
+ }
+
+ if (mad_frame_decode(frame, stream) == -1) {
+ if (!MAD_RECOVERABLE(stream->error))
+ break;
+
+ switch (error_func(error_data, stream, frame)) {
+ case MAD_FLOW_STOP:
+ goto done;
+ case MAD_FLOW_BREAK:
+ goto fail;
+ case MAD_FLOW_IGNORE:
+ break;
+ case MAD_FLOW_CONTINUE:
+ default:
+ continue;
+ }
+ }
+ else
+ bad_last_frame = 0;
+
+ if (decoder->filter_func) {
+ switch (decoder->filter_func(decoder->cb_data, stream, frame)) {
+ case MAD_FLOW_STOP:
+ goto done;
+ case MAD_FLOW_BREAK:
+ goto fail;
+ case MAD_FLOW_IGNORE:
+ continue;
+ case MAD_FLOW_CONTINUE:
+ break;
+ }
+ }
+
+ mad_synth_frame(synth, frame);
+
+ if (decoder->output_func) {
+ switch (decoder->output_func(decoder->cb_data,
+ &frame->header, &synth->pcm)) {
+ case MAD_FLOW_STOP:
+ goto done;
+ case MAD_FLOW_BREAK:
+ goto fail;
+ case MAD_FLOW_IGNORE:
+ case MAD_FLOW_CONTINUE:
+ break;
+ }
+ }
+ }
+ }
+ while (stream->error == MAD_ERROR_BUFLEN);
+
+ fail:
+ result = -1;
+
+ done:
+ mad_synth_finish(synth);
+ mad_frame_finish(frame);
+ mad_stream_finish(stream);
+
+ return result;
+}
+
+# if defined(USE_ASYNC)
+static
+int run_async(struct mad_decoder *decoder)
+{
+ pid_t pid;
+ int ptoc[2], ctop[2], flags;
+
+ if (pipe(ptoc) == -1)
+ return -1;
+
+ if (pipe(ctop) == -1) {
+ close(ptoc[0]);
+ close(ptoc[1]);
+ return -1;
+ }
+
+ flags = fcntl(ptoc[0], F_GETFL);
+ if (flags == -1 ||
+ fcntl(ptoc[0], F_SETFL, flags | O_NONBLOCK) == -1) {
+ close(ctop[0]);
+ close(ctop[1]);
+ close(ptoc[0]);
+ close(ptoc[1]);
+ return -1;
+ }
+
+ pid = fork();
+ if (pid == -1) {
+ close(ctop[0]);
+ close(ctop[1]);
+ close(ptoc[0]);
+ close(ptoc[1]);
+ return -1;
+ }
+
+ decoder->async.pid = pid;
+
+ if (pid) {
+ /* parent */
+
+ close(ptoc[0]);
+ close(ctop[1]);
+
+ decoder->async.in = ctop[0];
+ decoder->async.out = ptoc[1];
+
+ return 0;
+ }
+
+ /* child */
+
+ close(ptoc[1]);
+ close(ctop[0]);
+
+ decoder->async.in = ptoc[0];
+ decoder->async.out = ctop[1];
+
+ _exit(run_sync(decoder));
+
+ /* not reached */
+ return -1;
+}
+# endif
+
+/*
+ * NAME: decoder->run()
+ * DESCRIPTION: run the decoder thread either synchronously or asynchronously
+ */
+int mad_decoder_run(struct mad_decoder *decoder, enum mad_decoder_mode mode)
+{
+ int result;
+ int (*run)(struct mad_decoder *) = 0;
+
+ switch (decoder->mode = mode) {
+ case MAD_DECODER_MODE_SYNC:
+ run = run_sync;
+ break;
+
+ case MAD_DECODER_MODE_ASYNC:
+# if defined(USE_ASYNC)
+ run = run_async;
+# endif
+ break;
+ }
+
+ if (run == 0)
+ return -1;
+
+ decoder->sync = malloc(sizeof(*decoder->sync));
+ if (decoder->sync == 0)
+ return -1;
+
+ result = run(decoder);
+
+ free(decoder->sync);
+ decoder->sync = 0;
+
+ return result;
+}
+
+/*
+ * NAME: decoder->message()
+ * DESCRIPTION: send a message to and receive a reply from the decoder process
+ */
+int mad_decoder_message(struct mad_decoder *decoder,
+ void *message, unsigned int *len)
+{
+# if defined(USE_ASYNC)
+ if (decoder->mode != MAD_DECODER_MODE_ASYNC ||
+ send(decoder->async.out, message, *len) != MAD_FLOW_CONTINUE ||
+ receive(decoder->async.in, &message, len) != MAD_FLOW_CONTINUE)
+ return -1;
+
+ return 0;
+# else
+ return -1;
+# endif
+}
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