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-rw-r--r--src/libmad/stream.c160
1 files changed, 160 insertions, 0 deletions
diff --git a/src/libmad/stream.c b/src/libmad/stream.c
new file mode 100644
index 000000000..1813019f6
--- /dev/null
+++ b/src/libmad/stream.c
@@ -0,0 +1,160 @@
+/*
+ * libmad - MPEG audio decoder library
+ * Copyright (C) 2000-2003 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: stream.c,v 1.1 2003/08/14 03:57:13 shank Exp $
+ */
+
+# ifdef HAVE_CONFIG_H
+# include "config.h"
+# endif
+
+# include "global.h"
+
+# include <stdlib.h>
+
+# include "bit.h"
+# include "stream.h"
+
+/*
+ * NAME: stream->init()
+ * DESCRIPTION: initialize stream struct
+ */
+void mad_stream_init(struct mad_stream *stream)
+{
+ stream->buffer = 0;
+ stream->bufend = 0;
+ stream->skiplen = 0;
+
+ stream->sync = 0;
+ stream->freerate = 0;
+
+ stream->this_frame = 0;
+ stream->next_frame = 0;
+ mad_bit_init(&stream->ptr, 0);
+
+ mad_bit_init(&stream->anc_ptr, 0);
+ stream->anc_bitlen = 0;
+
+ stream->main_data = 0;
+ stream->md_len = 0;
+
+ stream->options = 0;
+ stream->error = MAD_ERROR_NONE;
+}
+
+/*
+ * NAME: stream->finish()
+ * DESCRIPTION: deallocate any dynamic memory associated with stream
+ */
+void mad_stream_finish(struct mad_stream *stream)
+{
+ if (stream->main_data) {
+ free(stream->main_data);
+ stream->main_data = 0;
+ }
+
+ mad_bit_finish(&stream->anc_ptr);
+ mad_bit_finish(&stream->ptr);
+}
+
+/*
+ * NAME: stream->buffer()
+ * DESCRIPTION: set stream buffer pointers
+ */
+void mad_stream_buffer(struct mad_stream *stream,
+ unsigned char const *buffer, unsigned long length)
+{
+ stream->buffer = buffer;
+ stream->bufend = buffer + length;
+
+ stream->this_frame = buffer;
+ stream->next_frame = buffer;
+
+ stream->sync = 1;
+
+ mad_bit_init(&stream->ptr, buffer);
+}
+
+/*
+ * NAME: stream->skip()
+ * DESCRIPTION: arrange to skip bytes before the next frame
+ */
+void mad_stream_skip(struct mad_stream *stream, unsigned long length)
+{
+ stream->skiplen += length;
+}
+
+/*
+ * NAME: stream->sync()
+ * DESCRIPTION: locate the next stream sync word
+ */
+int mad_stream_sync(struct mad_stream *stream)
+{
+ register unsigned char const *ptr, *end;
+
+ ptr = mad_bit_nextbyte(&stream->ptr);
+ end = stream->bufend;
+
+ while (ptr < end - 1 &&
+ !(ptr[0] == 0xff && (ptr[1] & 0xe0) == 0xe0))
+ ++ptr;
+
+ if (end - ptr < MAD_BUFFER_GUARD)
+ return -1;
+
+ mad_bit_init(&stream->ptr, ptr);
+
+ return 0;
+}
+
+/*
+ * NAME: stream->errorstr()
+ * DESCRIPTION: return a string description of the current error condition
+ */
+char const *mad_stream_errorstr(struct mad_stream const *stream)
+{
+ switch (stream->error) {
+ case MAD_ERROR_NONE: return "no error";
+
+ case MAD_ERROR_BUFLEN: return "input buffer too small (or EOF)";
+ case MAD_ERROR_BUFPTR: return "invalid (null) buffer pointer";
+
+ case MAD_ERROR_NOMEM: return "not enough memory";
+
+ case MAD_ERROR_LOSTSYNC: return "lost synchronization";
+ case MAD_ERROR_BADLAYER: return "reserved header layer value";
+ case MAD_ERROR_BADBITRATE: return "forbidden bitrate value";
+ case MAD_ERROR_BADSAMPLERATE: return "reserved sample frequency value";
+ case MAD_ERROR_BADEMPHASIS: return "reserved emphasis value";
+
+ case MAD_ERROR_BADCRC: return "CRC check failed";
+ case MAD_ERROR_BADBITALLOC: return "forbidden bit allocation value";
+ case MAD_ERROR_BADSCALEFACTOR: return "bad scalefactor index";
+ case MAD_ERROR_BADFRAMELEN: return "bad frame length";
+ case MAD_ERROR_BADBIGVALUES: return "bad big_values count";
+ case MAD_ERROR_BADBLOCKTYPE: return "reserved block_type";
+ case MAD_ERROR_BADSCFSI: return "bad scalefactor selection info";
+ case MAD_ERROR_BADDATAPTR: return "bad main_data_begin pointer";
+ case MAD_ERROR_BADPART3LEN: return "bad audio data length";
+ case MAD_ERROR_BADHUFFTABLE: return "bad Huffman table select";
+ case MAD_ERROR_BADHUFFDATA: return "Huffman data overrun";
+ case MAD_ERROR_BADSTEREO: return "incompatible block_type for JS";
+ }
+
+ return 0;
+}