--- /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 "module.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);
+}
+
+static 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,
+};
+
+static void bdrv_cloop_init(void)
+{
+ bdrv_register(&bdrv_cloop);
+}
+
+block_init(bdrv_cloop_init);
projects / qemu / blobdiff