mpv/stream/rar.c

456 lines
12 KiB
C

/*****************************************************************************
* rar.c: uncompressed RAR parser
*****************************************************************************
* Copyright (C) 2008-2010 Laurent Aimar
* $Id: f368245f4260f913f5c211e09b7dd511a96525e6 $
*
* Author: Laurent Aimar <fenrir _AT_ videolan _DOT_ org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
/*****************************************************************************
* Preamble
*****************************************************************************/
#include <assert.h>
#include <limits.h>
#include <stdio.h>
#include <libavutil/intreadwrite.h>
#include "talloc.h"
#include "common/common.h"
#include "stream.h"
#include "rar.h"
static const uint8_t rar_marker[] = {
0x52, 0x61, 0x72, 0x21, 0x1a, 0x07, 0x00
};
static const int rar_marker_size = sizeof(rar_marker);
void RarFileDelete(rar_file_t *file)
{
for (int i = 0; i < file->chunk_count; i++) {
free(file->chunk[i]->mrl);
free(file->chunk[i]);
}
talloc_free(file->chunk);
free(file->name);
free_stream(file->s);
free(file);
}
typedef struct {
uint16_t crc;
uint8_t type;
uint16_t flags;
uint16_t size;
uint32_t add_size;
} rar_block_t;
enum {
RAR_BLOCK_MARKER = 0x72,
RAR_BLOCK_ARCHIVE = 0x73,
RAR_BLOCK_FILE = 0x74,
RAR_BLOCK_SUBBLOCK = 0x7a,
RAR_BLOCK_END = 0x7b,
};
enum {
RAR_BLOCK_END_HAS_NEXT = 0x0001,
};
enum {
RAR_BLOCK_FILE_HAS_PREVIOUS = 0x0001,
RAR_BLOCK_FILE_HAS_NEXT = 0x0002,
RAR_BLOCK_FILE_HAS_HIGH = 0x0100,
};
static int PeekBlock(struct stream *s, rar_block_t *hdr)
{
bstr data = stream_peek(s, 11);
const uint8_t *peek = (uint8_t *)data.start;
int peek_size = data.len;
if (peek_size < 7)
return -1;
hdr->crc = AV_RL16(&peek[0]);
hdr->type = peek[2];
hdr->flags = AV_RL16(&peek[3]);
hdr->size = AV_RL16(&peek[5]);
hdr->add_size = 0;
if ((hdr->flags & 0x8000) ||
hdr->type == RAR_BLOCK_FILE ||
hdr->type == RAR_BLOCK_SUBBLOCK) {
if (peek_size < 11)
return -1;
hdr->add_size = AV_RL32(&peek[7]);
}
if (hdr->size < 7)
return -1;
return 0;
}
static int SkipBlock(struct stream *s, const rar_block_t *hdr)
{
uint64_t size = (uint64_t)hdr->size + hdr->add_size;
while (size > 0) {
int skip = MPMIN(size, INT_MAX);
if (!stream_skip(s, skip))
return -1;
size -= skip;
}
return 0;
}
static int IgnoreBlock(struct stream *s, int block)
{
/* */
rar_block_t bk;
if (PeekBlock(s, &bk) || bk.type != block)
return -1;
return SkipBlock(s, &bk);
}
static int SkipEnd(struct stream *s, const rar_block_t *hdr)
{
if (!(hdr->flags & RAR_BLOCK_END_HAS_NEXT))
return -1;
if (SkipBlock(s, hdr))
return -1;
/* Now, we need to look for a marker block,
* It seems that there is garbage at EOF */
for (;;) {
bstr peek = stream_peek(s, rar_marker_size);
if (peek.len < rar_marker_size)
return -1;
if (!memcmp(peek.start, rar_marker, rar_marker_size))
break;
if (!stream_skip(s, 1))
return -1;
}
/* Skip marker and archive blocks */
if (IgnoreBlock(s, RAR_BLOCK_MARKER))
return -1;
if (IgnoreBlock(s, RAR_BLOCK_ARCHIVE))
return -1;
return 0;
}
static int SkipFile(struct stream *s, int *count, rar_file_t ***file,
const rar_block_t *hdr, const char *volume_mrl)
{
int min_size = 7+21;
if (hdr->flags & RAR_BLOCK_FILE_HAS_HIGH)
min_size += 8;
if (hdr->size < (unsigned)min_size)
return -1;
bstr data = stream_peek(s, min_size);
if (data.len < min_size)
return -1;
const uint8_t *peek = (uint8_t *)data.start;
/* */
uint32_t file_size_low = AV_RL32(&peek[7+4]);
uint8_t method = peek[7+18];
uint16_t name_size = AV_RL16(&peek[7+19]);
uint32_t file_size_high = 0;
if (hdr->flags & RAR_BLOCK_FILE_HAS_HIGH)
file_size_high = AV_RL32(&peek[7+29]);
const uint64_t file_size = ((uint64_t)file_size_high << 32) | file_size_low;
char *name = calloc(1, name_size + 1);
if (!name)
return -1;
const int name_offset = (hdr->flags & RAR_BLOCK_FILE_HAS_HIGH) ? (7+33) : (7+25);
if (name_offset + name_size <= hdr->size) {
const int max_size = name_offset + name_size;
bstr namedata = stream_peek(s, max_size);
if (namedata.len < max_size) {
free(name);
return -1;
}
memcpy(name, &namedata.start[name_offset], name_size);
}
rar_file_t *current = NULL;
if (method != 0x30) {
MP_WARN(s, "Ignoring compressed file %s (method=0x%2.2x)\n", name, method);
goto exit;
}
/* */
if( *count > 0 )
current = (*file)[*count - 1];
if (current &&
(current->is_complete ||
strcmp(current->name, name) ||
(hdr->flags & RAR_BLOCK_FILE_HAS_PREVIOUS) == 0))
current = NULL;
if (!current) {
if (hdr->flags & RAR_BLOCK_FILE_HAS_PREVIOUS)
goto exit;
current = calloc(1, sizeof(*current));
if (!current)
goto exit;
MP_TARRAY_APPEND(NULL, *file, *count, current);
current->name = name;
current->size = file_size;
current->is_complete = false;
current->real_size = 0;
current->chunk_count = 0;
current->chunk = NULL;
name = NULL;
}
/* Append chunks */
rar_file_chunk_t *chunk = malloc(sizeof(*chunk));
if (chunk) {
chunk->mrl = strdup(volume_mrl);
chunk->offset = stream_tell(s) + hdr->size;
chunk->size = hdr->add_size;
chunk->cummulated_size = 0;
if (current->chunk_count > 0) {
rar_file_chunk_t *previous = current->chunk[current->chunk_count-1];
chunk->cummulated_size += previous->cummulated_size +
previous->size;
}
MP_TARRAY_APPEND(NULL, current->chunk, current->chunk_count, chunk);
current->real_size += hdr->add_size;
}
if ((hdr->flags & RAR_BLOCK_FILE_HAS_NEXT) == 0)
current->is_complete = true;
exit:
/* */
free(name);
/* We stop on the first non empty file if we cannot seek */
if (current) {
bool can_seek = s->end_pos > 0;
if (!can_seek && current->size > 0)
return -1;
}
if (SkipBlock(s, hdr))
return -1;
return 0;
}
int RarProbe(struct stream *s)
{
bstr peek = stream_peek(s, rar_marker_size);
if (peek.len < rar_marker_size)
return -1;
if (memcmp(peek.start, rar_marker, rar_marker_size))
return -1;
return 0;
}
typedef struct {
const char *match;
const char *format;
int start;
int stop;
} rar_pattern_t;
static const rar_pattern_t *FindVolumePattern(const char *location)
{
static const rar_pattern_t patterns[] = {
{ ".part1.rar", "%s.part%.1d.rar", 2, 9 },
{ ".part01.rar", "%s.part%.2d.rar", 2, 99, },
{ ".part001.rar", "%s.part%.3d.rar", 2, 999 },
{ ".rar", "%s.%c%.2d", 0, 999 },
{ NULL, NULL, 0, 0 },
};
const size_t location_size = strlen(location);
for (int i = 0; patterns[i].match != NULL; i++) {
const size_t match_size = strlen(patterns[i].match);
if (location_size < match_size)
continue;
if (!strcmp(&location[location_size - match_size], patterns[i].match))
return &patterns[i];
}
return NULL;
}
int RarParse(struct stream *s, int *count, rar_file_t ***file)
{
*count = 0;
*file = NULL;
const rar_pattern_t *pattern = FindVolumePattern(s->url);
int volume_offset = 0;
char *volume_mrl;
if (asprintf(&volume_mrl, "%s", s->url) < 0)
return -1;
struct stream *vol = s;
for (;;) {
/* Skip marker & archive */
if (IgnoreBlock(vol, RAR_BLOCK_MARKER) ||
IgnoreBlock(vol, RAR_BLOCK_ARCHIVE)) {
if (vol != s)
free_stream(vol);
free(volume_mrl);
return -1;
}
/* */
int has_next = -1;
for (;;) {
rar_block_t bk;
int ret;
if (PeekBlock(vol, &bk))
break;
switch(bk.type) {
case RAR_BLOCK_END:
ret = SkipEnd(vol, &bk);
has_next = ret && (bk.flags & RAR_BLOCK_END_HAS_NEXT);
break;
case RAR_BLOCK_FILE:
ret = SkipFile(vol, count, file, &bk, volume_mrl);
break;
default:
ret = SkipBlock(vol, &bk);
break;
}
if (ret)
break;
}
if (has_next < 0 && *count > 0 && !(*file)[*count -1]->is_complete)
has_next = 1;
if (vol != s)
free_stream(vol);
if (!has_next || !pattern)
goto done;
/* Open next volume */
const int volume_index = pattern->start + volume_offset++;
if (volume_index > pattern->stop)
goto done;
char *volume_base;
if (asprintf(&volume_base, "%.*s",
(int)(strlen(s->url) - strlen(pattern->match)), s->url) < 0) {
goto done;
}
free(volume_mrl);
if (pattern->start) {
if (asprintf(&volume_mrl, pattern->format, volume_base, volume_index) < 0)
volume_mrl = NULL;
} else {
if (asprintf(&volume_mrl, pattern->format, volume_base,
'r' + volume_index / 100, volume_index % 100) < 0)
volume_mrl = NULL;
}
free(volume_base);
if (!volume_mrl)
goto done;
vol = stream_create(volume_mrl, STREAM_READ | STREAM_NO_FILTERS,
s->cancel, s->global);
if (!vol)
goto done;
}
done:
free(volume_mrl);
if (*count == 0) {
talloc_free(*file);
return -1;
}
return 0;
}
int RarSeek(rar_file_t *file, uint64_t position)
{
if (position > file->real_size)
position = file->real_size;
/* Search the chunk */
const rar_file_chunk_t *old_chunk = file->current_chunk;
for (int i = 0; i < file->chunk_count; i++) {
file->current_chunk = file->chunk[i];
if (position < file->current_chunk->cummulated_size + file->current_chunk->size)
break;
}
file->i_pos = position;
const uint64_t offset = file->current_chunk->offset +
(position - file->current_chunk->cummulated_size);
if (strcmp(old_chunk->mrl, file->current_chunk->mrl)) {
if (file->s)
free_stream(file->s);
file->s = stream_create(file->current_chunk->mrl,
STREAM_READ | STREAM_NO_FILTERS,
file->cancel, file->global);
}
return file->s ? stream_seek(file->s, offset) : 0;
}
ssize_t RarRead(rar_file_t *file, void *data, size_t size)
{
size_t total = 0;
while (total < size) {
const uint64_t chunk_end = file->current_chunk->cummulated_size + file->current_chunk->size;
int max = MPMIN(MPMIN((int64_t)(size - total), (int64_t)(chunk_end - file->i_pos)), INT_MAX);
if (max <= 0)
break;
int r = file->s ? stream_read(file->s, data, max) : -1;
if (r <= 0)
break;
total += r;
if( data )
data = (char *)data + r;
file->i_pos += r;
if (file->i_pos >= chunk_end &&
RarSeek(file, file->i_pos))
break;
}
return total;
}