mirror of
https://github.com/vgmstream/vgmstream.git
synced 2024-12-24 12:24:50 +01:00
77 lines
2.3 KiB
C
77 lines
2.3 KiB
C
#ifndef _OGG_VORBIS_STREAMFILE_H_
|
|
#define _OGG_VORBIS_STREAMFILE_H_
|
|
#include "../streamfile.h"
|
|
|
|
|
|
typedef struct {
|
|
int is_encrypted;
|
|
uint8_t key[0x100];
|
|
size_t key_len;
|
|
int is_nibble_swap;
|
|
int is_header_swap;
|
|
} ogg_vorbis_io_config_data;
|
|
|
|
typedef struct {
|
|
/* config */
|
|
ogg_vorbis_io_config_data cfg;
|
|
} ogg_vorbis_io_data;
|
|
|
|
|
|
static size_t ogg_vorbis_io_read(STREAMFILE *streamfile, uint8_t *dest, off_t offset, size_t length, ogg_vorbis_io_data* data) {
|
|
size_t bytes_read;
|
|
int i;
|
|
static const uint8_t header_swap[4] = { 0x4F,0x67,0x67,0x53 }; /* "OggS" */
|
|
static const size_t header_size = 0x04;
|
|
|
|
bytes_read = streamfile->read(streamfile, dest, offset, length);
|
|
|
|
if (data->cfg.is_encrypted) {
|
|
for (i = 0; i < bytes_read; i++) {
|
|
if (data->cfg.is_header_swap && (offset + i) < header_size) {
|
|
dest[i] = header_swap[(offset + i) % header_size];
|
|
}
|
|
else {
|
|
if (!data->cfg.key_len && !data->cfg.is_nibble_swap)
|
|
break;
|
|
if (data->cfg.key_len)
|
|
dest[i] ^= data->cfg.key[(offset + i) % data->cfg.key_len];
|
|
if (data->cfg.is_nibble_swap)
|
|
dest[i] = ((dest[i] << 4) & 0xf0) | ((dest[i] >> 4) & 0x0f);
|
|
}
|
|
}
|
|
}
|
|
|
|
return bytes_read;
|
|
}
|
|
|
|
//todo maybe use generic decryption streamfile
|
|
static STREAMFILE* setup_ogg_vorbis_streamfile(STREAMFILE *streamFile, ogg_vorbis_io_config_data cfg) {
|
|
STREAMFILE *temp_streamFile = NULL, *new_streamFile = NULL;
|
|
ogg_vorbis_io_data io_data = {0};
|
|
size_t io_data_size = sizeof(ogg_vorbis_io_data);
|
|
|
|
/* setup decryption */
|
|
io_data.cfg = cfg; /* memcpy */
|
|
|
|
|
|
/* setup custom streamfile */
|
|
new_streamFile = open_wrap_streamfile(streamFile);
|
|
if (!new_streamFile) goto fail;
|
|
temp_streamFile = new_streamFile;
|
|
|
|
//todo extension .ogg?
|
|
|
|
new_streamFile = open_io_streamfile(temp_streamFile, &io_data,io_data_size, ogg_vorbis_io_read,NULL);
|
|
if (!new_streamFile) goto fail;
|
|
temp_streamFile = new_streamFile;
|
|
|
|
return temp_streamFile;
|
|
|
|
fail:
|
|
close_streamfile(temp_streamFile);
|
|
return NULL;
|
|
}
|
|
|
|
|
|
#endif /* _OGG_VORBIS_STREAMFILE_H_ */
|