diff options
author | Anthony Liguori <aliguori@us.ibm.com> | 2009-05-09 17:14:19 -0500 |
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committer | Anthony Liguori <aliguori@us.ibm.com> | 2009-05-14 16:13:46 -0500 |
commit | 019d6b8ff0d495ded6977f24a4e8fd1c7fec09e0 (patch) | |
tree | ffaf507f7440b5c7d8ed8a4de193b1df41e4a2d8 /block/dmg.c | |
parent | 5efa9d5a8b18841c9c62208a494d7f519238979a (diff) |
Move block drivers into their own directory
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
Diffstat (limited to 'block/dmg.c')
-rw-r--r-- | block/dmg.c | 301 |
1 files changed, 301 insertions, 0 deletions
diff --git a/block/dmg.c b/block/dmg.c new file mode 100644 index 0000000000..262560ffd3 --- /dev/null +++ b/block/dmg.c @@ -0,0 +1,301 @@ +/* + * QEMU Block driver for DMG 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 "bswap.h" +#include "module.h" +#include <zlib.h> + +typedef struct BDRVDMGState { + int fd; + + /* each chunk contains a certain number of sectors, + * offsets[i] is the offset in the .dmg file, + * lengths[i] is the length of the compressed chunk, + * sectors[i] is the sector beginning at offsets[i], + * sectorcounts[i] is the number of sectors in that chunk, + * the sectors array is ordered + * 0<=i<n_chunks */ + + uint32_t n_chunks; + uint32_t* types; + uint64_t* offsets; + uint64_t* lengths; + uint64_t* sectors; + uint64_t* sectorcounts; + uint32_t current_chunk; + uint8_t *compressed_chunk; + uint8_t *uncompressed_chunk; + z_stream zstream; +} BDRVDMGState; + +static int dmg_probe(const uint8_t *buf, int buf_size, const char *filename) +{ + int len=strlen(filename); + if(len>4 && !strcmp(filename+len-4,".dmg")) + return 2; + return 0; +} + +static off_t read_off(int fd) +{ + uint64_t buffer; + if(read(fd,&buffer,8)<8) + return 0; + return be64_to_cpu(buffer); +} + +static off_t read_uint32(int fd) +{ + uint32_t buffer; + if(read(fd,&buffer,4)<4) + return 0; + return be32_to_cpu(buffer); +} + +static int dmg_open(BlockDriverState *bs, const char *filename, int flags) +{ + BDRVDMGState *s = bs->opaque; + off_t info_begin,info_end,last_in_offset,last_out_offset; + uint32_t count; + uint32_t max_compressed_size=1,max_sectors_per_chunk=1,i; + + s->fd = open(filename, O_RDONLY | O_BINARY); + if (s->fd < 0) + return -errno; + bs->read_only = 1; + s->n_chunks = 0; + s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL; + + /* read offset of info blocks */ + if(lseek(s->fd,-0x1d8,SEEK_END)<0) { +dmg_close: + close(s->fd); + /* open raw instead */ + bs->drv=bdrv_find_format("raw"); + return bs->drv->bdrv_open(bs, filename, flags); + } + info_begin=read_off(s->fd); + if(info_begin==0) + goto dmg_close; + if(lseek(s->fd,info_begin,SEEK_SET)<0) + goto dmg_close; + if(read_uint32(s->fd)!=0x100) + goto dmg_close; + if((count = read_uint32(s->fd))==0) + goto dmg_close; + info_end = info_begin+count; + if(lseek(s->fd,0xf8,SEEK_CUR)<0) + goto dmg_close; + + /* read offsets */ + last_in_offset = last_out_offset = 0; + while(lseek(s->fd,0,SEEK_CUR)<info_end) { + uint32_t type; + + count = read_uint32(s->fd); + if(count==0) + goto dmg_close; + type = read_uint32(s->fd); + if(type!=0x6d697368 || count<244) + lseek(s->fd,count-4,SEEK_CUR); + else { + int new_size, chunk_count; + if(lseek(s->fd,200,SEEK_CUR)<0) + goto dmg_close; + chunk_count = (count-204)/40; + new_size = sizeof(uint64_t) * (s->n_chunks + chunk_count); + s->types = qemu_realloc(s->types, new_size/2); + s->offsets = qemu_realloc(s->offsets, new_size); + s->lengths = qemu_realloc(s->lengths, new_size); + s->sectors = qemu_realloc(s->sectors, new_size); + s->sectorcounts = qemu_realloc(s->sectorcounts, new_size); + + for(i=s->n_chunks;i<s->n_chunks+chunk_count;i++) { + s->types[i] = read_uint32(s->fd); + if(s->types[i]!=0x80000005 && s->types[i]!=1 && s->types[i]!=2) { + if(s->types[i]==0xffffffff) { + last_in_offset = s->offsets[i-1]+s->lengths[i-1]; + last_out_offset = s->sectors[i-1]+s->sectorcounts[i-1]; + } + chunk_count--; + i--; + if(lseek(s->fd,36,SEEK_CUR)<0) + goto dmg_close; + continue; + } + read_uint32(s->fd); + s->sectors[i] = last_out_offset+read_off(s->fd); + s->sectorcounts[i] = read_off(s->fd); + s->offsets[i] = last_in_offset+read_off(s->fd); + s->lengths[i] = read_off(s->fd); + if(s->lengths[i]>max_compressed_size) + max_compressed_size = s->lengths[i]; + if(s->sectorcounts[i]>max_sectors_per_chunk) + max_sectors_per_chunk = s->sectorcounts[i]; + } + s->n_chunks+=chunk_count; + } + } + + /* initialize zlib engine */ + s->compressed_chunk = qemu_malloc(max_compressed_size+1); + s->uncompressed_chunk = qemu_malloc(512*max_sectors_per_chunk); + if(inflateInit(&s->zstream) != Z_OK) + goto dmg_close; + + s->current_chunk = s->n_chunks; + + return 0; +} + +static inline int is_sector_in_chunk(BDRVDMGState* s, + uint32_t chunk_num,int sector_num) +{ + if(chunk_num>=s->n_chunks || s->sectors[chunk_num]>sector_num || + s->sectors[chunk_num]+s->sectorcounts[chunk_num]<=sector_num) + return 0; + else + return -1; +} + +static inline uint32_t search_chunk(BDRVDMGState* s,int sector_num) +{ + /* binary search */ + uint32_t chunk1=0,chunk2=s->n_chunks,chunk3; + while(chunk1!=chunk2) { + chunk3 = (chunk1+chunk2)/2; + if(s->sectors[chunk3]>sector_num) + chunk2 = chunk3; + else if(s->sectors[chunk3]+s->sectorcounts[chunk3]>sector_num) + return chunk3; + else + chunk1 = chunk3; + } + return s->n_chunks; /* error */ +} + +static inline int dmg_read_chunk(BDRVDMGState *s,int sector_num) +{ + if(!is_sector_in_chunk(s,s->current_chunk,sector_num)) { + int ret; + uint32_t chunk = search_chunk(s,sector_num); + + if(chunk>=s->n_chunks) + return -1; + + s->current_chunk = s->n_chunks; + switch(s->types[chunk]) { + case 0x80000005: { /* zlib compressed */ + int i; + + ret = lseek(s->fd, s->offsets[chunk], SEEK_SET); + if(ret<0) + return -1; + + /* we need to buffer, because only the chunk as whole can be + * inflated. */ + i=0; + do { + ret = read(s->fd, s->compressed_chunk+i, s->lengths[chunk]-i); + if(ret<0 && errno==EINTR) + ret=0; + i+=ret; + } while(ret>=0 && ret+i<s->lengths[chunk]); + + if (ret != s->lengths[chunk]) + return -1; + + s->zstream.next_in = s->compressed_chunk; + s->zstream.avail_in = s->lengths[chunk]; + s->zstream.next_out = s->uncompressed_chunk; + s->zstream.avail_out = 512*s->sectorcounts[chunk]; + 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 != 512*s->sectorcounts[chunk]) + return -1; + break; } + case 1: /* copy */ + ret = read(s->fd, s->uncompressed_chunk, s->lengths[chunk]); + if (ret != s->lengths[chunk]) + return -1; + break; + case 2: /* zero */ + memset(s->uncompressed_chunk, 0, 512*s->sectorcounts[chunk]); + break; + } + s->current_chunk = chunk; + } + return 0; +} + +static int dmg_read(BlockDriverState *bs, int64_t sector_num, + uint8_t *buf, int nb_sectors) +{ + BDRVDMGState *s = bs->opaque; + int i; + + for(i=0;i<nb_sectors;i++) { + uint32_t sector_offset_in_chunk; + if(dmg_read_chunk(s, sector_num+i) != 0) + return -1; + sector_offset_in_chunk = sector_num+i-s->sectors[s->current_chunk]; + memcpy(buf+i*512,s->uncompressed_chunk+sector_offset_in_chunk*512,512); + } + return 0; +} + +static void dmg_close(BlockDriverState *bs) +{ + BDRVDMGState *s = bs->opaque; + close(s->fd); + if(s->n_chunks>0) { + free(s->types); + free(s->offsets); + free(s->lengths); + free(s->sectors); + free(s->sectorcounts); + } + free(s->compressed_chunk); + free(s->uncompressed_chunk); + inflateEnd(&s->zstream); +} + +static BlockDriver bdrv_dmg = { + .format_name = "dmg", + .instance_size = sizeof(BDRVDMGState), + .bdrv_probe = dmg_probe, + .bdrv_open = dmg_open, + .bdrv_read = dmg_read, + .bdrv_close = dmg_close, +}; + +static void bdrv_dmg_init(void) +{ + bdrv_register(&bdrv_dmg); +} + +block_init(bdrv_dmg_init); |