f40bfc9267
Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97 Reviewed-on: http://gerrit.rockbox.org/137 Reviewed-by: Nils Wallménius <nils@rockbox.org> Tested-by: Nils Wallménius <nils@rockbox.org>
170 lines
4.6 KiB
C
170 lines
4.6 KiB
C
////////////////////////////////////////////////////////////////////////////
|
|
// **** WAVPACK **** //
|
|
// Hybrid Lossless Wavefile Compressor //
|
|
// Copyright (c) 1998 - 2004 Conifer Software. //
|
|
// All Rights Reserved. //
|
|
// Distributed under the BSD Software License (see license.txt) //
|
|
////////////////////////////////////////////////////////////////////////////
|
|
|
|
// bits.c
|
|
|
|
// This module provides utilities to support the BitStream structure which is
|
|
// used to read and write all WavPack audio data streams. It also contains a
|
|
// wrapper for the stream I/O functions and a set of functions dealing with
|
|
// endian-ness, both for enhancing portability. Finally, a debug wrapper for
|
|
// the malloc() system is provided.
|
|
|
|
#include "wavpack.h"
|
|
#include "system.h"
|
|
|
|
#include <string.h>
|
|
|
|
////////////////////////// Bitstream functions ////////////////////////////////
|
|
|
|
// Open the specified BitStream and associate with the specified buffer.
|
|
|
|
static void bs_read (Bitstream *bs);
|
|
|
|
void bs_open_read (Bitstream *bs, uchar *buffer_start, uchar *buffer_end, read_stream file, uint32_t file_bytes)
|
|
{
|
|
CLEAR (*bs);
|
|
bs->buf = buffer_start;
|
|
bs->end = buffer_end;
|
|
|
|
if (file) {
|
|
bs->ptr = bs->end - 1;
|
|
bs->file_bytes = file_bytes;
|
|
bs->file = file;
|
|
}
|
|
else
|
|
bs->ptr = bs->buf - 1;
|
|
|
|
bs->wrap = bs_read;
|
|
}
|
|
|
|
// This function is only called from the getbit() and getbits() macros when
|
|
// the BitStream has been exhausted and more data is required. Sinve these
|
|
// bistreams no longer access files, this function simple sets an error and
|
|
// resets the buffer.
|
|
|
|
static void bs_read (Bitstream *bs)
|
|
{
|
|
if (bs->file && bs->file_bytes) {
|
|
uint32_t bytes_read, bytes_to_read = bs->end - bs->buf;
|
|
|
|
if (bytes_to_read > bs->file_bytes)
|
|
bytes_to_read = bs->file_bytes;
|
|
|
|
bytes_read = bs->file (bs->buf, bytes_to_read);
|
|
|
|
if (bytes_read) {
|
|
bs->end = bs->buf + bytes_read;
|
|
bs->file_bytes -= bytes_read;
|
|
}
|
|
else {
|
|
memset (bs->buf, -1, bs->end - bs->buf);
|
|
bs->error = 1;
|
|
}
|
|
}
|
|
else
|
|
bs->error = 1;
|
|
|
|
if (bs->error)
|
|
memset (bs->buf, -1, bs->end - bs->buf);
|
|
|
|
bs->ptr = bs->buf;
|
|
}
|
|
|
|
// Open the specified BitStream using the specified buffer pointers. It is
|
|
// assumed that enough buffer space has been allocated for all data that will
|
|
// be written, otherwise an error will be generated.
|
|
|
|
static void bs_write (Bitstream *bs);
|
|
|
|
void bs_open_write (Bitstream *bs, uchar *buffer_start, uchar *buffer_end)
|
|
{
|
|
bs->error = bs->sr = bs->bc = 0;
|
|
bs->ptr = bs->buf = buffer_start;
|
|
bs->end = buffer_end;
|
|
bs->wrap = bs_write;
|
|
}
|
|
|
|
// This function is only called from the putbit() and putbits() macros when
|
|
// the buffer is full, which is now flagged as an error.
|
|
|
|
static void bs_write (Bitstream *bs)
|
|
{
|
|
bs->ptr = bs->buf;
|
|
bs->error = 1;
|
|
}
|
|
|
|
// This function forces a flushing write of the specified BitStream, and
|
|
// returns the total number of bytes written into the buffer.
|
|
|
|
uint32_t bs_close_write (Bitstream *bs)
|
|
{
|
|
uint32_t bytes_written;
|
|
|
|
if (bs->error)
|
|
return (uint32_t) -1;
|
|
|
|
while (bs->bc || ((bs->ptr - bs->buf) & 1)) putbit_1 (bs);
|
|
bytes_written = bs->ptr - bs->buf;
|
|
CLEAR (*bs);
|
|
return bytes_written;
|
|
}
|
|
|
|
/////////////////////// Endian Correction Routines ////////////////////////////
|
|
|
|
void little_endian_to_native (void *data, char *format)
|
|
{
|
|
uchar *cp = (uchar *) data;
|
|
|
|
while (*format) {
|
|
switch (*format) {
|
|
case 'L':
|
|
*(long *)cp = letoh32(*(long *)cp);
|
|
cp += 4;
|
|
break;
|
|
|
|
case 'S':
|
|
*(short *)cp = letoh16(*(short *)cp);
|
|
cp += 2;
|
|
break;
|
|
|
|
default:
|
|
if (*format >= '0' && *format <= '9')
|
|
cp += *format - '0';
|
|
|
|
break;
|
|
}
|
|
|
|
format++;
|
|
}
|
|
}
|
|
|
|
void native_to_little_endian (void *data, char *format)
|
|
{
|
|
uchar *cp = (uchar *) data;
|
|
|
|
while (*format) {
|
|
switch (*format) {
|
|
case 'L':
|
|
*(long *)cp = htole32(*(long *)cp);
|
|
cp += 4;
|
|
break;
|
|
|
|
case 'S':
|
|
*(short *)cp = htole16(*(short *)cp);
|
|
cp += 2;
|
|
break;
|
|
|
|
default:
|
|
if (*format >= '0' && *format <= '9')
|
|
cp += *format - '0';
|
|
break;
|
|
}
|
|
|
|
format++;
|
|
}
|
|
}
|