[qemu.git] / block / dmg.c

/*
 * 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/block_int.h"
#include "qemu/bswap.h"
#include "qemu/module.h"
#include <zlib.h>

typedef struct BDRVDMGState {
    CoMutex lock;
    /* 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;

    if (!filename) {
        return 0;
    }

    len = strlen(filename);
    if (len > 4 && !strcmp(filename + len - 4, ".dmg")) {
        return 2;
    }
    return 0;
}

static int read_uint64(BlockDriverState *bs, int64_t offset, uint64_t *result)
{
    uint64_t buffer;
    int ret;

    ret = bdrv_pread(bs->file, offset, &buffer, 8);
    if (ret < 0) {
        return ret;
    }

    *result = be64_to_cpu(buffer);
    return 0;
}

static int read_uint32(BlockDriverState *bs, int64_t offset, uint32_t *result)
{
    uint32_t buffer;
    int ret;

    ret = bdrv_pread(bs->file, offset, &buffer, 4);
    if (ret < 0) {
        return ret;
    }

    *result = be32_to_cpu(buffer);
    return 0;
}

static int dmg_open(BlockDriverState *bs, QDict *options, int flags,
                    Error **errp)
{
    BDRVDMGState *s = bs->opaque;
    uint64_t info_begin,info_end,last_in_offset,last_out_offset;
    uint32_t count, tmp;
    uint32_t max_compressed_size=1,max_sectors_per_chunk=1,i;
    int64_t offset;
    int ret;

    bs->read_only = 1;
    s->n_chunks = 0;
    s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL;

    /* read offset of info blocks */
    offset = bdrv_getlength(bs->file);
    if (offset < 0) {
        ret = offset;
        goto fail;
    }
    offset -= 0x1d8;

    ret = read_uint64(bs, offset, &info_begin);
    if (ret < 0) {
        goto fail;
    } else if (info_begin == 0) {
        ret = -EINVAL;
        goto fail;
    }

    ret = read_uint32(bs, info_begin, &tmp);
    if (ret < 0) {
        goto fail;
    } else if (tmp != 0x100) {
        ret = -EINVAL;
        goto fail;
    }

    ret = read_uint32(bs, info_begin + 4, &count);
    if (ret < 0) {
        goto fail;
    } else if (count == 0) {
        ret = -EINVAL;
        goto fail;
    }
    info_end = info_begin + count;

    offset = info_begin + 0x100;

    /* read offsets */
    last_in_offset = last_out_offset = 0;
    while (offset < info_end) {
        uint32_t type;

        ret = read_uint32(bs, offset, &count);
        if (ret < 0) {
            goto fail;
        } else if (count == 0) {
            ret = -EINVAL;
            goto fail;
        }
        offset += 4;

        ret = read_uint32(bs, offset, &type);
        if (ret < 0) {
            goto fail;
        }

	if (type == 0x6d697368 && count >= 244) {
	    int new_size, chunk_count;

            offset += 4;
            offset += 200;

	    chunk_count = (count-204)/40;
	    new_size = sizeof(uint64_t) * (s->n_chunks + chunk_count);
	    s->types = g_realloc(s->types, new_size/2);
	    s->offsets = g_realloc(s->offsets, new_size);
	    s->lengths = g_realloc(s->lengths, new_size);
	    s->sectors = g_realloc(s->sectors, new_size);
	    s->sectorcounts = g_realloc(s->sectorcounts, new_size);

            for (i = s->n_chunks; i < s->n_chunks + chunk_count; i++) {
                ret = read_uint32(bs, offset, &s->types[i]);
                if (ret < 0) {
                    goto fail;
                }
		offset += 4;
		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--;
		    offset += 36;
		    continue;
		}
		offset += 4;

                ret = read_uint64(bs, offset, &s->sectors[i]);
                if (ret < 0) {
                    goto fail;
                }
                s->sectors[i] += last_out_offset;
                offset += 8;

                ret = read_uint64(bs, offset, &s->sectorcounts[i]);
                if (ret < 0) {
                    goto fail;
                }
                offset += 8;

                ret = read_uint64(bs, offset, &s->offsets[i]);
                if (ret < 0) {
                    goto fail;
                }
                s->offsets[i] += last_in_offset;
                offset += 8;

                ret = read_uint64(bs, offset, &s->lengths[i]);
                if (ret < 0) {
                    goto fail;
                }
                offset += 8;

		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 = g_malloc(max_compressed_size+1);
    s->uncompressed_chunk = g_malloc(512*max_sectors_per_chunk);
    if(inflateInit(&s->zstream) != Z_OK) {
        ret = -EINVAL;
        goto fail;
    }

    s->current_chunk = s->n_chunks;

    qemu_co_mutex_init(&s->lock);
    return 0;

fail:
    g_free(s->types);
    g_free(s->offsets);
    g_free(s->lengths);
    g_free(s->sectors);
    g_free(s->sectorcounts);
    g_free(s->compressed_chunk);
    g_free(s->uncompressed_chunk);
    return ret;
}

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(BlockDriverState *bs, int sector_num)
{
    BDRVDMGState *s = bs->opaque;

    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;

	    /* we need to buffer, because only the chunk as whole can be
	     * inflated. */
	    i=0;
	    do {
                ret = bdrv_pread(bs->file, s->offsets[chunk] + i,
                                 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 = bdrv_pread(bs->file, s->offsets[chunk],
                             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(bs, 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 coroutine_fn int dmg_co_read(BlockDriverState *bs, int64_t sector_num,
                                    uint8_t *buf, int nb_sectors)
{
    int ret;
    BDRVDMGState *s = bs->opaque;
    qemu_co_mutex_lock(&s->lock);
    ret = dmg_read(bs, sector_num, buf, nb_sectors);
    qemu_co_mutex_unlock(&s->lock);
    return ret;
}

static void dmg_close(BlockDriverState *bs)
{
    BDRVDMGState *s = bs->opaque;

    g_free(s->types);
    g_free(s->offsets);
    g_free(s->lengths);
    g_free(s->sectors);
    g_free(s->sectorcounts);
    g_free(s->compressed_chunk);
    g_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_co_read,
    .bdrv_close		= dmg_close,
};

static void bdrv_dmg_init(void)
{
    bdrv_register(&bdrv_dmg);
}

block_init(bdrv_dmg_init);
Commit	Line	Data
585d0ed9 FB	1	/*
585d0ed9 FB	2	* QEMU Block driver for DMG images
5fafdf24	3	*
585d0ed9	4	* Copyright (c) 2004 Johannes E. Schindelin
5fafdf24	5	*
585d0ed9 FB	6	* Permission is hereby granted, free of charge, to any person obtaining a copy
	7	* of this software and associated documentation files (the "Software"), to deal
	8	* in the Software without restriction, including without limitation the rights
	9	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	10	* copies of the Software, and to permit persons to whom the Software is
	11	* furnished to do so, subject to the following conditions:
	12	*
	13	* The above copyright notice and this permission notice shall be included in
	14	* all copies or substantial portions of the Software.
	15	*
	16	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	17	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	18	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	19	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	20	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	21	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	22	* THE SOFTWARE.
	23	*/
faf07963	24	#include "qemu-common.h"
737e150e	25	#include "block/block_int.h"
1de7afc9 PB	26	#include "qemu/bswap.h"
1de7afc9 PB	27	#include "qemu/module.h"
585d0ed9 FB	28	#include <zlib.h>
	29
	30	typedef struct BDRVDMGState {
848c66e8	31	CoMutex lock;
585d0ed9 FB	32	/* each chunk contains a certain number of sectors,
	33	* offsets[i] is the offset in the .dmg file,
	34	* lengths[i] is the length of the compressed chunk,
	35	* sectors[i] is the sector beginning at offsets[i],
	36	* sectorcounts[i] is the number of sectors in that chunk,
	37	* the sectors array is ordered
	38	* 0<=i<n_chunks */
	39
	40	uint32_t n_chunks;
	41	uint32_t* types;
	42	uint64_t* offsets;
	43	uint64_t* lengths;
	44	uint64_t* sectors;
	45	uint64_t* sectorcounts;
	46	uint32_t current_chunk;
28a5c9c8 FB	47	uint8_t *compressed_chunk;
28a5c9c8 FB	48	uint8_t *uncompressed_chunk;
585d0ed9 FB	49	z_stream zstream;
	50	} BDRVDMGState;
	51
	52	static int dmg_probe(const uint8_t buf, int buf_size, const char filename)
	53	{
f5866fa4 KW	54	int len;
	55
	56	if (!filename) {
	57	return 0;
	58	}
	59
	60	len = strlen(filename);
	61	if (len > 4 && !strcmp(filename + len - 4, ".dmg")) {
	62	return 2;
	63	}
585d0ed9 FB	64	return 0;
	65	}
	66
69d34a36	67	static int read_uint64(BlockDriverState bs, int64_t offset, uint64_t result)
585d0ed9	68	{
69d34a36 KW	69	uint64_t buffer;
	70	int ret;
	71
	72	ret = bdrv_pread(bs->file, offset, &buffer, 8);
	73	if (ret < 0) {
	74	return ret;
	75	}
	76
	77	*result = be64_to_cpu(buffer);
	78	return 0;
585d0ed9 FB	79	}
585d0ed9 FB	80
69d34a36	81	static int read_uint32(BlockDriverState bs, int64_t offset, uint32_t result)
585d0ed9	82	{
69d34a36 KW	83	uint32_t buffer;
	84	int ret;
	85
	86	ret = bdrv_pread(bs->file, offset, &buffer, 4);
	87	if (ret < 0) {
	88	return ret;
	89	}
	90
	91	*result = be32_to_cpu(buffer);
	92	return 0;
585d0ed9 FB	93	}
585d0ed9 FB	94
015a1036 HR	95	static int dmg_open(BlockDriverState bs, QDict options, int flags,
015a1036 HR	96	Error **errp)
585d0ed9 FB	97	{
585d0ed9 FB	98	BDRVDMGState *s = bs->opaque;
69d34a36 KW	99	uint64_t info_begin,info_end,last_in_offset,last_out_offset;
69d34a36 KW	100	uint32_t count, tmp;
585d0ed9	101	uint32_t max_compressed_size=1,max_sectors_per_chunk=1,i;
16cdf7ce	102	int64_t offset;
69d34a36	103	int ret;
585d0ed9	104
585d0ed9 FB	105	bs->read_only = 1;
585d0ed9 FB	106	s->n_chunks = 0;
511d2b14	107	s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL;
3b46e624	108
585d0ed9	109	/* read offset of info blocks */
64a31d5c	110	offset = bdrv_getlength(bs->file);
16cdf7ce	111	if (offset < 0) {
69d34a36	112	ret = offset;
1559ca00	113	goto fail;
585d0ed9	114	}
64a31d5c	115	offset -= 0x1d8;
1559ca00	116
69d34a36 KW	117	ret = read_uint64(bs, offset, &info_begin);
	118	if (ret < 0) {
	119	goto fail;
	120	} else if (info_begin == 0) {
	121	ret = -EINVAL;
	122	goto fail;
16cdf7ce CH	123	}
16cdf7ce CH	124
69d34a36 KW	125	ret = read_uint32(bs, info_begin, &tmp);
	126	if (ret < 0) {
	127	goto fail;
	128	} else if (tmp != 0x100) {
	129	ret = -EINVAL;
16cdf7ce CH	130	goto fail;
	131	}
	132
69d34a36 KW	133	ret = read_uint32(bs, info_begin + 4, &count);
	134	if (ret < 0) {
	135	goto fail;
	136	} else if (count == 0) {
	137	ret = -EINVAL;
16cdf7ce CH	138	goto fail;
	139	}
	140	info_end = info_begin + count;
	141
	142	offset = info_begin + 0x100;
585d0ed9 FB	143
	144	/* read offsets */
	145	last_in_offset = last_out_offset = 0;
16cdf7ce	146	while (offset < info_end) {
995179f1 FB	147	uint32_t type;
995179f1 FB	148
69d34a36 KW	149	ret = read_uint32(bs, offset, &count);
	150	if (ret < 0) {
	151	goto fail;
	152	} else if (count == 0) {
	153	ret = -EINVAL;
	154	goto fail;
	155	}
16cdf7ce CH	156	offset += 4;
16cdf7ce CH	157
69d34a36 KW	158	ret = read_uint32(bs, offset, &type);
	159	if (ret < 0) {
	160	goto fail;
	161	}
	162
16cdf7ce	163	if (type == 0x6d697368 && count >= 244) {
585d0ed9	164	int new_size, chunk_count;
16cdf7ce CH	165
	166	offset += 4;
	167	offset += 200;
	168
585d0ed9 FB	169	chunk_count = (count-204)/40;
585d0ed9 FB	170	new_size = sizeof(uint64_t) * (s->n_chunks + chunk_count);
7267c094 AL	171	s->types = g_realloc(s->types, new_size/2);
	172	s->offsets = g_realloc(s->offsets, new_size);
	173	s->lengths = g_realloc(s->lengths, new_size);
	174	s->sectors = g_realloc(s->sectors, new_size);
	175	s->sectorcounts = g_realloc(s->sectorcounts, new_size);
585d0ed9	176
69d34a36 KW	177	for (i = s->n_chunks; i < s->n_chunks + chunk_count; i++) {
	178	ret = read_uint32(bs, offset, &s->types[i]);
	179	if (ret < 0) {
	180	goto fail;
	181	}
16cdf7ce	182	offset += 4;
585d0ed9 FB	183	if(s->types[i]!=0x80000005 && s->types[i]!=1 && s->types[i]!=2) {
	184	if(s->types[i]==0xffffffff) {
	185	last_in_offset = s->offsets[i-1]+s->lengths[i-1];
	186	last_out_offset = s->sectors[i-1]+s->sectorcounts[i-1];
	187	}
	188	chunk_count--;
	189	i--;
16cdf7ce	190	offset += 36;
585d0ed9 FB	191	continue;
585d0ed9 FB	192	}
16cdf7ce CH	193	offset += 4;
16cdf7ce CH	194
69d34a36 KW	195	ret = read_uint64(bs, offset, &s->sectors[i]);
	196	if (ret < 0) {
	197	goto fail;
	198	}
	199	s->sectors[i] += last_out_offset;
	200	offset += 8;
16cdf7ce	201
69d34a36 KW	202	ret = read_uint64(bs, offset, &s->sectorcounts[i]);
	203	if (ret < 0) {
	204	goto fail;
	205	}
	206	offset += 8;
16cdf7ce	207
69d34a36 KW	208	ret = read_uint64(bs, offset, &s->offsets[i]);
	209	if (ret < 0) {
	210	goto fail;
	211	}
	212	s->offsets[i] += last_in_offset;
	213	offset += 8;
16cdf7ce	214
69d34a36 KW	215	ret = read_uint64(bs, offset, &s->lengths[i]);
	216	if (ret < 0) {
	217	goto fail;
	218	}
	219	offset += 8;
16cdf7ce	220
585d0ed9 FB	221	if(s->lengths[i]>max_compressed_size)
	222	max_compressed_size = s->lengths[i];
	223	if(s->sectorcounts[i]>max_sectors_per_chunk)
	224	max_sectors_per_chunk = s->sectorcounts[i];
	225	}
	226	s->n_chunks+=chunk_count;
	227	}
	228	}
	229
	230	/* initialize zlib engine */
7267c094 AL	231	s->compressed_chunk = g_malloc(max_compressed_size+1);
7267c094 AL	232	s->uncompressed_chunk = g_malloc(512*max_sectors_per_chunk);
69d34a36 KW	233	if(inflateInit(&s->zstream) != Z_OK) {
	234	ret = -EINVAL;
	235	goto fail;
	236	}
585d0ed9 FB	237
585d0ed9 FB	238	s->current_chunk = s->n_chunks;
3b46e624	239
848c66e8	240	qemu_co_mutex_init(&s->lock);
585d0ed9	241	return 0;
69d34a36	242
1559ca00	243	fail:
69d34a36 KW	244	g_free(s->types);
	245	g_free(s->offsets);
	246	g_free(s->lengths);
	247	g_free(s->sectors);
	248	g_free(s->sectorcounts);
	249	g_free(s->compressed_chunk);
	250	g_free(s->uncompressed_chunk);
	251	return ret;
585d0ed9 FB	252	}
	253
	254	static inline int is_sector_in_chunk(BDRVDMGState* s,
	255	uint32_t chunk_num,int sector_num)
	256	{
	257	if(chunk_num>=s->n_chunks \|\| s->sectors[chunk_num]>sector_num \|\|
	258	s->sectors[chunk_num]+s->sectorcounts[chunk_num]<=sector_num)
	259	return 0;
	260	else
	261	return -1;
	262	}
	263
	264	static inline uint32_t search_chunk(BDRVDMGState* s,int sector_num)
	265	{
	266	/* binary search */
	267	uint32_t chunk1=0,chunk2=s->n_chunks,chunk3;
	268	while(chunk1!=chunk2) {
	269	chunk3 = (chunk1+chunk2)/2;
	270	if(s->sectors[chunk3]>sector_num)
	271	chunk2 = chunk3;
	272	else if(s->sectors[chunk3]+s->sectorcounts[chunk3]>sector_num)
	273	return chunk3;
	274	else
	275	chunk1 = chunk3;
	276	}
	277	return s->n_chunks; /* error */
	278	}
	279
64a31d5c	280	static inline int dmg_read_chunk(BlockDriverState *bs, int sector_num)
585d0ed9	281	{
64a31d5c CH	282	BDRVDMGState *s = bs->opaque;
64a31d5c CH	283
585d0ed9 FB	284	if(!is_sector_in_chunk(s,s->current_chunk,sector_num)) {
	285	int ret;
	286	uint32_t chunk = search_chunk(s,sector_num);
	287
	288	if(chunk>=s->n_chunks)
	289	return -1;
	290
	291	s->current_chunk = s->n_chunks;
	292	switch(s->types[chunk]) {
	293	case 0x80000005: { /* zlib compressed */
	294	int i;
	295
585d0ed9 FB	296	/* we need to buffer, because only the chunk as whole can be
	297	* inflated. */
	298	i=0;
	299	do {
64a31d5c CH	300	ret = bdrv_pread(bs->file, s->offsets[chunk] + i,
64a31d5c CH	301	s->compressed_chunk+i, s->lengths[chunk]-i);
585d0ed9 FB	302	if(ret<0 && errno==EINTR)
	303	ret=0;
	304	i+=ret;
	305	} while(ret>=0 && ret+i<s->lengths[chunk]);
	306
	307	if (ret != s->lengths[chunk])
	308	return -1;
5fafdf24	309
585d0ed9 FB	310	s->zstream.next_in = s->compressed_chunk;
	311	s->zstream.avail_in = s->lengths[chunk];
	312	s->zstream.next_out = s->uncompressed_chunk;
	313	s->zstream.avail_out = 512*s->sectorcounts[chunk];
	314	ret = inflateReset(&s->zstream);
	315	if(ret != Z_OK)
	316	return -1;
	317	ret = inflate(&s->zstream, Z_FINISH);
	318	if(ret != Z_STREAM_END \|\| s->zstream.total_out != 512*s->sectorcounts[chunk])
	319	return -1;
	320	break; }
	321	case 1: /* copy */
64a31d5c CH	322	ret = bdrv_pread(bs->file, s->offsets[chunk],
64a31d5c CH	323	s->uncompressed_chunk, s->lengths[chunk]);
585d0ed9 FB	324	if (ret != s->lengths[chunk])
	325	return -1;
	326	break;
	327	case 2: /* zero */
	328	memset(s->uncompressed_chunk, 0, 512*s->sectorcounts[chunk]);
	329	break;
	330	}
	331	s->current_chunk = chunk;
	332	}
	333	return 0;
	334	}
	335
5fafdf24	336	static int dmg_read(BlockDriverState *bs, int64_t sector_num,
585d0ed9 FB	337	uint8_t *buf, int nb_sectors)
	338	{
	339	BDRVDMGState *s = bs->opaque;
	340	int i;
	341
	342	for(i=0;i<nb_sectors;i++) {
	343	uint32_t sector_offset_in_chunk;
64a31d5c	344	if(dmg_read_chunk(bs, sector_num+i) != 0)
585d0ed9 FB	345	return -1;
	346	sector_offset_in_chunk = sector_num+i-s->sectors[s->current_chunk];
	347	memcpy(buf+i512,s->uncompressed_chunk+sector_offset_in_chunk512,512);
	348	}
	349	return 0;
	350	}
	351
2914caa0 PB	352	static coroutine_fn int dmg_co_read(BlockDriverState *bs, int64_t sector_num,
	353	uint8_t *buf, int nb_sectors)
	354	{
	355	int ret;
	356	BDRVDMGState *s = bs->opaque;
	357	qemu_co_mutex_lock(&s->lock);
	358	ret = dmg_read(bs, sector_num, buf, nb_sectors);
	359	qemu_co_mutex_unlock(&s->lock);
	360	return ret;
	361	}
	362
585d0ed9 FB	363	static void dmg_close(BlockDriverState *bs)
	364	{
	365	BDRVDMGState *s = bs->opaque;
4f8aa2e1 KW	366
	367	g_free(s->types);
	368	g_free(s->offsets);
	369	g_free(s->lengths);
	370	g_free(s->sectors);
	371	g_free(s->sectorcounts);
	372	g_free(s->compressed_chunk);
	373	g_free(s->uncompressed_chunk);
	374
585d0ed9 FB	375	inflateEnd(&s->zstream);
	376	}
	377
5efa9d5a	378	static BlockDriver bdrv_dmg = {
e60f469c AJ	379	.format_name = "dmg",
	380	.instance_size = sizeof(BDRVDMGState),
	381	.bdrv_probe = dmg_probe,
64a31d5c	382	.bdrv_open = dmg_open,
2914caa0	383	.bdrv_read = dmg_co_read,
e60f469c	384	.bdrv_close = dmg_close,
585d0ed9	385	};
5efa9d5a AL	386
	387	static void bdrv_dmg_init(void)
	388	{
	389	bdrv_register(&bdrv_dmg);
	390	}
	391
	392	block_init(bdrv_dmg_init);