diff options
| -rw-r--r-- | block/cloop.c | 32 |
1 files changed, 17 insertions, 15 deletions
diff --git a/block/cloop.c b/block/cloop.c index e4f995b5d6..9fe2a42363 100644 --- a/block/cloop.c +++ b/block/cloop.c @@ -62,23 +62,22 @@ static int cloop_open(BlockDriverState *bs, const char *filename, int flags) bs->read_only = 1; /* read header */ - if(lseek(s->fd,128,SEEK_SET)<0) { -cloop_close: - close(s->fd); - return -1; + if (pread(s->fd, &s->block_size, 4, 128) < 4) { + goto cloop_close; } - 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); + s->block_size = be32_to_cpu(s->block_size); + + if (pread(s->fd, &s->n_blocks, 4, 128 + 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) + offsets_size = s->n_blocks * sizeof(uint64_t); + s->offsets = qemu_malloc(offsets_size); + if (pread(s->fd, s->offsets, offsets_size, 128 + 4 + 4) < 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) { @@ -98,6 +97,10 @@ cloop_close: s->sectors_per_block = s->block_size/512; bs->total_sectors = s->n_blocks*s->sectors_per_block; return 0; + +cloop_close: + close(s->fd); + return -1; } static inline int cloop_read_block(BDRVCloopState *s,int block_num) @@ -106,8 +109,7 @@ static inline int cloop_read_block(BDRVCloopState *s,int 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); + ret = pread(s->fd, s->compressed_block, bytes, s->offsets[block_num]); if (ret != bytes) return -1; |