+++ /dev/null
-/*
- * QEMU Block driver for CLOOP images
- *
- * Copyright (c) 2004 Johannes E. Schindelin
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
- * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
- * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
- * THE SOFTWARE.
- */
-#include "qemu-common.h"
-#include "block_int.h"
-#include <zlib.h>
-
-typedef struct BDRVCloopState {
- int fd;
- uint32_t block_size;
- uint32_t n_blocks;
- uint64_t* offsets;
- uint32_t sectors_per_block;
- uint32_t current_block;
- uint8_t *compressed_block;
- uint8_t *uncompressed_block;
- z_stream zstream;
-} BDRVCloopState;
-
-static int cloop_probe(const uint8_t *buf, int buf_size, const char *filename)
-{
- const char* magic_version_2_0="#!/bin/sh\n"
- "#V2.0 Format\n"
- "modprobe cloop file=$0 && mount -r -t iso9660 /dev/cloop $1\n";
- int length=strlen(magic_version_2_0);
- if(length>buf_size)
- length=buf_size;
- if(!memcmp(magic_version_2_0,buf,length))
- return 2;
- return 0;
-}
-
-static int cloop_open(BlockDriverState *bs, const char *filename, int flags)
-{
- BDRVCloopState *s = bs->opaque;
- uint32_t offsets_size,max_compressed_block_size=1,i;
-
- s->fd = open(filename, O_RDONLY | O_BINARY);
- if (s->fd < 0)
- return -errno;
- bs->read_only = 1;
-
- /* read header */
- if(lseek(s->fd,128,SEEK_SET)<0) {
-cloop_close:
- close(s->fd);
- return -1;
- }
- if(read(s->fd,&s->block_size,4)<4)
- goto cloop_close;
- s->block_size=be32_to_cpu(s->block_size);
- if(read(s->fd,&s->n_blocks,4)<4)
- goto cloop_close;
- s->n_blocks=be32_to_cpu(s->n_blocks);
-
- /* read offsets */
- offsets_size=s->n_blocks*sizeof(uint64_t);
- s->offsets=(uint64_t*)qemu_malloc(offsets_size);
- if(read(s->fd,s->offsets,offsets_size)<offsets_size)
- goto cloop_close;
- for(i=0;i<s->n_blocks;i++) {
- s->offsets[i]=be64_to_cpu(s->offsets[i]);
- if(i>0) {
- uint32_t size=s->offsets[i]-s->offsets[i-1];
- if(size>max_compressed_block_size)
- max_compressed_block_size=size;
- }
- }
-
- /* initialize zlib engine */
- s->compressed_block = qemu_malloc(max_compressed_block_size+1);
- s->uncompressed_block = qemu_malloc(s->block_size);
- if(inflateInit(&s->zstream) != Z_OK)
- goto cloop_close;
- s->current_block=s->n_blocks;
-
- s->sectors_per_block = s->block_size/512;
- bs->total_sectors = s->n_blocks*s->sectors_per_block;
- return 0;
-}
-
-static inline int cloop_read_block(BDRVCloopState *s,int block_num)
-{
- if(s->current_block != block_num) {
- int ret;
- uint32_t bytes = s->offsets[block_num+1]-s->offsets[block_num];
-
- lseek(s->fd, s->offsets[block_num], SEEK_SET);
- ret = read(s->fd, s->compressed_block, bytes);
- if (ret != bytes)
- return -1;
-
- s->zstream.next_in = s->compressed_block;
- s->zstream.avail_in = bytes;
- s->zstream.next_out = s->uncompressed_block;
- s->zstream.avail_out = s->block_size;
- ret = inflateReset(&s->zstream);
- if(ret != Z_OK)
- return -1;
- ret = inflate(&s->zstream, Z_FINISH);
- if(ret != Z_STREAM_END || s->zstream.total_out != s->block_size)
- return -1;
-
- s->current_block = block_num;
- }
- return 0;
-}
-
-static int cloop_read(BlockDriverState *bs, int64_t sector_num,
- uint8_t *buf, int nb_sectors)
-{
- BDRVCloopState *s = bs->opaque;
- int i;
-
- for(i=0;i<nb_sectors;i++) {
- uint32_t sector_offset_in_block=((sector_num+i)%s->sectors_per_block),
- block_num=(sector_num+i)/s->sectors_per_block;
- if(cloop_read_block(s, block_num) != 0)
- return -1;
- memcpy(buf+i*512,s->uncompressed_block+sector_offset_in_block*512,512);
- }
- return 0;
-}
-
-static void cloop_close(BlockDriverState *bs)
-{
- BDRVCloopState *s = bs->opaque;
- close(s->fd);
- if(s->n_blocks>0)
- free(s->offsets);
- free(s->compressed_block);
- free(s->uncompressed_block);
- inflateEnd(&s->zstream);
-}
-
-BlockDriver bdrv_cloop = {
- .format_name = "cloop",
- .instance_size = sizeof(BDRVCloopState),
- .bdrv_probe = cloop_probe,
- .bdrv_open = cloop_open,
- .bdrv_read = cloop_read,
- .bdrv_close = cloop_close,
-};
projects / qemu / blobdiff