[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)
{
    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
1a86938f	95	static int dmg_open(BlockDriverState bs, QDict options, int flags)
585d0ed9 FB	96	{
585d0ed9 FB	97	BDRVDMGState *s = bs->opaque;
69d34a36 KW	98	uint64_t info_begin,info_end,last_in_offset,last_out_offset;
69d34a36 KW	99	uint32_t count, tmp;
585d0ed9	100	uint32_t max_compressed_size=1,max_sectors_per_chunk=1,i;
16cdf7ce	101	int64_t offset;
69d34a36	102	int ret;
585d0ed9	103
585d0ed9 FB	104	bs->read_only = 1;
585d0ed9 FB	105	s->n_chunks = 0;
511d2b14	106	s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL;
3b46e624	107
585d0ed9	108	/* read offset of info blocks */
64a31d5c	109	offset = bdrv_getlength(bs->file);
16cdf7ce	110	if (offset < 0) {
69d34a36	111	ret = offset;
1559ca00	112	goto fail;
585d0ed9	113	}
64a31d5c	114	offset -= 0x1d8;
1559ca00	115
69d34a36 KW	116	ret = read_uint64(bs, offset, &info_begin);
	117	if (ret < 0) {
	118	goto fail;
	119	} else if (info_begin == 0) {
	120	ret = -EINVAL;
	121	goto fail;
16cdf7ce CH	122	}
16cdf7ce CH	123
69d34a36 KW	124	ret = read_uint32(bs, info_begin, &tmp);
	125	if (ret < 0) {
	126	goto fail;
	127	} else if (tmp != 0x100) {
	128	ret = -EINVAL;
16cdf7ce CH	129	goto fail;
	130	}
	131
69d34a36 KW	132	ret = read_uint32(bs, info_begin + 4, &count);
	133	if (ret < 0) {
	134	goto fail;
	135	} else if (count == 0) {
	136	ret = -EINVAL;
16cdf7ce CH	137	goto fail;
	138	}
	139	info_end = info_begin + count;
	140
	141	offset = info_begin + 0x100;
585d0ed9 FB	142
	143	/* read offsets */
	144	last_in_offset = last_out_offset = 0;
16cdf7ce	145	while (offset < info_end) {
995179f1 FB	146	uint32_t type;
995179f1 FB	147
69d34a36 KW	148	ret = read_uint32(bs, offset, &count);
	149	if (ret < 0) {
	150	goto fail;
	151	} else if (count == 0) {
	152	ret = -EINVAL;
	153	goto fail;
	154	}
16cdf7ce CH	155	offset += 4;
16cdf7ce CH	156
69d34a36 KW	157	ret = read_uint32(bs, offset, &type);
	158	if (ret < 0) {
	159	goto fail;
	160	}
	161
16cdf7ce	162	if (type == 0x6d697368 && count >= 244) {
585d0ed9	163	int new_size, chunk_count;
16cdf7ce CH	164
	165	offset += 4;
	166	offset += 200;
	167
585d0ed9 FB	168	chunk_count = (count-204)/40;
585d0ed9 FB	169	new_size = sizeof(uint64_t) * (s->n_chunks + chunk_count);
7267c094 AL	170	s->types = g_realloc(s->types, new_size/2);
	171	s->offsets = g_realloc(s->offsets, new_size);
	172	s->lengths = g_realloc(s->lengths, new_size);
	173	s->sectors = g_realloc(s->sectors, new_size);
	174	s->sectorcounts = g_realloc(s->sectorcounts, new_size);
585d0ed9	175
69d34a36 KW	176	for (i = s->n_chunks; i < s->n_chunks + chunk_count; i++) {
	177	ret = read_uint32(bs, offset, &s->types[i]);
	178	if (ret < 0) {
	179	goto fail;
	180	}
16cdf7ce	181	offset += 4;
585d0ed9 FB	182	if(s->types[i]!=0x80000005 && s->types[i]!=1 && s->types[i]!=2) {
	183	if(s->types[i]==0xffffffff) {
	184	last_in_offset = s->offsets[i-1]+s->lengths[i-1];
	185	last_out_offset = s->sectors[i-1]+s->sectorcounts[i-1];
	186	}
	187	chunk_count--;
	188	i--;
16cdf7ce	189	offset += 36;
585d0ed9 FB	190	continue;
585d0ed9 FB	191	}
16cdf7ce CH	192	offset += 4;
16cdf7ce CH	193
69d34a36 KW	194	ret = read_uint64(bs, offset, &s->sectors[i]);
	195	if (ret < 0) {
	196	goto fail;
	197	}
	198	s->sectors[i] += last_out_offset;
	199	offset += 8;
16cdf7ce	200
69d34a36 KW	201	ret = read_uint64(bs, offset, &s->sectorcounts[i]);
	202	if (ret < 0) {
	203	goto fail;
	204	}
	205	offset += 8;
16cdf7ce	206
69d34a36 KW	207	ret = read_uint64(bs, offset, &s->offsets[i]);
	208	if (ret < 0) {
	209	goto fail;
	210	}
	211	s->offsets[i] += last_in_offset;
	212	offset += 8;
16cdf7ce	213
69d34a36 KW	214	ret = read_uint64(bs, offset, &s->lengths[i]);
	215	if (ret < 0) {
	216	goto fail;
	217	}
	218	offset += 8;
16cdf7ce	219
585d0ed9 FB	220	if(s->lengths[i]>max_compressed_size)
	221	max_compressed_size = s->lengths[i];
	222	if(s->sectorcounts[i]>max_sectors_per_chunk)
	223	max_sectors_per_chunk = s->sectorcounts[i];
	224	}
	225	s->n_chunks+=chunk_count;
	226	}
	227	}
	228
	229	/* initialize zlib engine */
7267c094 AL	230	s->compressed_chunk = g_malloc(max_compressed_size+1);
7267c094 AL	231	s->uncompressed_chunk = g_malloc(512*max_sectors_per_chunk);
69d34a36 KW	232	if(inflateInit(&s->zstream) != Z_OK) {
	233	ret = -EINVAL;
	234	goto fail;
	235	}
585d0ed9 FB	236
585d0ed9 FB	237	s->current_chunk = s->n_chunks;
3b46e624	238
848c66e8	239	qemu_co_mutex_init(&s->lock);
585d0ed9	240	return 0;
69d34a36	241
1559ca00	242	fail:
69d34a36 KW	243	g_free(s->types);
	244	g_free(s->offsets);
	245	g_free(s->lengths);
	246	g_free(s->sectors);
	247	g_free(s->sectorcounts);
	248	g_free(s->compressed_chunk);
	249	g_free(s->uncompressed_chunk);
	250	return ret;
585d0ed9 FB	251	}
	252
	253	static inline int is_sector_in_chunk(BDRVDMGState* s,
	254	uint32_t chunk_num,int sector_num)
	255	{
	256	if(chunk_num>=s->n_chunks \|\| s->sectors[chunk_num]>sector_num \|\|
	257	s->sectors[chunk_num]+s->sectorcounts[chunk_num]<=sector_num)
	258	return 0;
	259	else
	260	return -1;
	261	}
	262
	263	static inline uint32_t search_chunk(BDRVDMGState* s,int sector_num)
	264	{
	265	/* binary search */
	266	uint32_t chunk1=0,chunk2=s->n_chunks,chunk3;
	267	while(chunk1!=chunk2) {
	268	chunk3 = (chunk1+chunk2)/2;
	269	if(s->sectors[chunk3]>sector_num)
	270	chunk2 = chunk3;
	271	else if(s->sectors[chunk3]+s->sectorcounts[chunk3]>sector_num)
	272	return chunk3;
	273	else
	274	chunk1 = chunk3;
	275	}
	276	return s->n_chunks; /* error */
	277	}
	278
64a31d5c	279	static inline int dmg_read_chunk(BlockDriverState *bs, int sector_num)
585d0ed9	280	{
64a31d5c CH	281	BDRVDMGState *s = bs->opaque;
64a31d5c CH	282
585d0ed9 FB	283	if(!is_sector_in_chunk(s,s->current_chunk,sector_num)) {
	284	int ret;
	285	uint32_t chunk = search_chunk(s,sector_num);
	286
	287	if(chunk>=s->n_chunks)
	288	return -1;
	289
	290	s->current_chunk = s->n_chunks;
	291	switch(s->types[chunk]) {
	292	case 0x80000005: { /* zlib compressed */
	293	int i;
	294
585d0ed9 FB	295	/* we need to buffer, because only the chunk as whole can be
	296	* inflated. */
	297	i=0;
	298	do {
64a31d5c CH	299	ret = bdrv_pread(bs->file, s->offsets[chunk] + i,
64a31d5c CH	300	s->compressed_chunk+i, s->lengths[chunk]-i);
585d0ed9 FB	301	if(ret<0 && errno==EINTR)
	302	ret=0;
	303	i+=ret;
	304	} while(ret>=0 && ret+i<s->lengths[chunk]);
	305
	306	if (ret != s->lengths[chunk])
	307	return -1;
5fafdf24	308
585d0ed9 FB	309	s->zstream.next_in = s->compressed_chunk;
	310	s->zstream.avail_in = s->lengths[chunk];
	311	s->zstream.next_out = s->uncompressed_chunk;
	312	s->zstream.avail_out = 512*s->sectorcounts[chunk];
	313	ret = inflateReset(&s->zstream);
	314	if(ret != Z_OK)
	315	return -1;
	316	ret = inflate(&s->zstream, Z_FINISH);
	317	if(ret != Z_STREAM_END \|\| s->zstream.total_out != 512*s->sectorcounts[chunk])
	318	return -1;
	319	break; }
	320	case 1: /* copy */
64a31d5c CH	321	ret = bdrv_pread(bs->file, s->offsets[chunk],
64a31d5c CH	322	s->uncompressed_chunk, s->lengths[chunk]);
585d0ed9 FB	323	if (ret != s->lengths[chunk])
	324	return -1;
	325	break;
	326	case 2: /* zero */
	327	memset(s->uncompressed_chunk, 0, 512*s->sectorcounts[chunk]);
	328	break;
	329	}
	330	s->current_chunk = chunk;
	331	}
	332	return 0;
	333	}
	334
5fafdf24	335	static int dmg_read(BlockDriverState *bs, int64_t sector_num,
585d0ed9 FB	336	uint8_t *buf, int nb_sectors)
	337	{
	338	BDRVDMGState *s = bs->opaque;
	339	int i;
	340
	341	for(i=0;i<nb_sectors;i++) {
	342	uint32_t sector_offset_in_chunk;
64a31d5c	343	if(dmg_read_chunk(bs, sector_num+i) != 0)
585d0ed9 FB	344	return -1;
	345	sector_offset_in_chunk = sector_num+i-s->sectors[s->current_chunk];
	346	memcpy(buf+i512,s->uncompressed_chunk+sector_offset_in_chunk512,512);
	347	}
	348	return 0;
	349	}
	350
2914caa0 PB	351	static coroutine_fn int dmg_co_read(BlockDriverState *bs, int64_t sector_num,
	352	uint8_t *buf, int nb_sectors)
	353	{
	354	int ret;
	355	BDRVDMGState *s = bs->opaque;
	356	qemu_co_mutex_lock(&s->lock);
	357	ret = dmg_read(bs, sector_num, buf, nb_sectors);
	358	qemu_co_mutex_unlock(&s->lock);
	359	return ret;
	360	}
	361
585d0ed9 FB	362	static void dmg_close(BlockDriverState *bs)
	363	{
	364	BDRVDMGState *s = bs->opaque;
4f8aa2e1 KW	365
	366	g_free(s->types);
	367	g_free(s->offsets);
	368	g_free(s->lengths);
	369	g_free(s->sectors);
	370	g_free(s->sectorcounts);
	371	g_free(s->compressed_chunk);
	372	g_free(s->uncompressed_chunk);
	373
585d0ed9 FB	374	inflateEnd(&s->zstream);
	375	}
	376
5efa9d5a	377	static BlockDriver bdrv_dmg = {
e60f469c AJ	378	.format_name = "dmg",
	379	.instance_size = sizeof(BDRVDMGState),
	380	.bdrv_probe = dmg_probe,
64a31d5c	381	.bdrv_open = dmg_open,
2914caa0	382	.bdrv_read = dmg_co_read,
e60f469c	383	.bdrv_close = dmg_close,
585d0ed9	384	};
5efa9d5a AL	385
	386	static void bdrv_dmg_init(void)
	387	{
	388	bdrv_register(&bdrv_dmg);
	389	}
	390
	391	block_init(bdrv_dmg_init);