[mirror_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>

enum {
    /* Limit chunk sizes to prevent unreasonable amounts of memory being used
     * or truncating when converting to 32-bit types
     */
    DMG_LENGTHS_MAX = 64 * 1024 * 1024, /* 64 MB */
    DMG_SECTORCOUNTS_MAX = DMG_LENGTHS_MAX / 512,
};

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) {
            size_t new_size;
            uint32_t 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 && i > 0) {
                        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;

                if (s->sectorcounts[i] > DMG_SECTORCOUNTS_MAX) {
                    error_report("sector count %" PRIu64 " for chunk %u is "
                                 "larger than max (%u)",
                                 s->sectorcounts[i], i, DMG_SECTORCOUNTS_MAX);
                    ret = -EINVAL;
                    goto fail;
                }

                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] > DMG_LENGTHS_MAX) {
                    error_report("length %" PRIu64 " for chunk %u is larger "
                                 "than max (%u)",
                                 s->lengths[i], i, DMG_LENGTHS_MAX);
                    ret = -EINVAL;
                    goto fail;
                }

                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 */
            /* we need to buffer, because only the chunk as whole can be
             * inflated. */
            ret = bdrv_pread(bs->file, s->offsets[chunk],
                             s->compressed_chunk, 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>
585d0ed9 FB	29
c165f775 SH	30	enum {
	31	/* Limit chunk sizes to prevent unreasonable amounts of memory being used
	32	* or truncating when converting to 32-bit types
	33	*/
	34	DMG_LENGTHS_MAX = 64 * 1024 * 1024, /* 64 MB */
	35	DMG_SECTORCOUNTS_MAX = DMG_LENGTHS_MAX / 512,
	36	};
	37
585d0ed9	38	typedef struct BDRVDMGState {
848c66e8	39	CoMutex lock;
585d0ed9 FB	40	/* each chunk contains a certain number of sectors,
	41	* offsets[i] is the offset in the .dmg file,
	42	* lengths[i] is the length of the compressed chunk,
	43	* sectors[i] is the sector beginning at offsets[i],
	44	* sectorcounts[i] is the number of sectors in that chunk,
	45	* the sectors array is ordered
	46	* 0<=i<n_chunks */
	47
	48	uint32_t n_chunks;
	49	uint32_t* types;
	50	uint64_t* offsets;
	51	uint64_t* lengths;
	52	uint64_t* sectors;
	53	uint64_t* sectorcounts;
	54	uint32_t current_chunk;
28a5c9c8 FB	55	uint8_t *compressed_chunk;
28a5c9c8 FB	56	uint8_t *uncompressed_chunk;
585d0ed9 FB	57	z_stream zstream;
	58	} BDRVDMGState;
	59
	60	static int dmg_probe(const uint8_t buf, int buf_size, const char filename)
	61	{
f5866fa4 KW	62	int len;
	63
	64	if (!filename) {
	65	return 0;
	66	}
	67
	68	len = strlen(filename);
	69	if (len > 4 && !strcmp(filename + len - 4, ".dmg")) {
	70	return 2;
	71	}
585d0ed9 FB	72	return 0;
	73	}
	74
69d34a36	75	static int read_uint64(BlockDriverState bs, int64_t offset, uint64_t result)
585d0ed9	76	{
69d34a36 KW	77	uint64_t buffer;
	78	int ret;
	79
	80	ret = bdrv_pread(bs->file, offset, &buffer, 8);
	81	if (ret < 0) {
	82	return ret;
	83	}
	84
	85	*result = be64_to_cpu(buffer);
	86	return 0;
585d0ed9 FB	87	}
585d0ed9 FB	88
69d34a36	89	static int read_uint32(BlockDriverState bs, int64_t offset, uint32_t result)
585d0ed9	90	{
69d34a36 KW	91	uint32_t buffer;
	92	int ret;
	93
	94	ret = bdrv_pread(bs->file, offset, &buffer, 4);
	95	if (ret < 0) {
	96	return ret;
	97	}
	98
	99	*result = be32_to_cpu(buffer);
	100	return 0;
585d0ed9 FB	101	}
585d0ed9 FB	102
015a1036 HR	103	static int dmg_open(BlockDriverState bs, QDict options, int flags,
015a1036 HR	104	Error **errp)
585d0ed9 FB	105	{
585d0ed9 FB	106	BDRVDMGState *s = bs->opaque;
2c1885ad	107	uint64_t info_begin, info_end, last_in_offset, last_out_offset;
69d34a36	108	uint32_t count, tmp;
2c1885ad	109	uint32_t max_compressed_size = 1, max_sectors_per_chunk = 1, i;
16cdf7ce	110	int64_t offset;
69d34a36	111	int ret;
585d0ed9	112
585d0ed9 FB	113	bs->read_only = 1;
585d0ed9 FB	114	s->n_chunks = 0;
511d2b14	115	s->offsets = s->lengths = s->sectors = s->sectorcounts = NULL;
3b46e624	116
585d0ed9	117	/* read offset of info blocks */
64a31d5c	118	offset = bdrv_getlength(bs->file);
16cdf7ce	119	if (offset < 0) {
69d34a36	120	ret = offset;
1559ca00	121	goto fail;
585d0ed9	122	}
64a31d5c	123	offset -= 0x1d8;
1559ca00	124
69d34a36 KW	125	ret = read_uint64(bs, offset, &info_begin);
	126	if (ret < 0) {
	127	goto fail;
	128	} else if (info_begin == 0) {
	129	ret = -EINVAL;
	130	goto fail;
16cdf7ce CH	131	}
16cdf7ce CH	132
69d34a36 KW	133	ret = read_uint32(bs, info_begin, &tmp);
	134	if (ret < 0) {
	135	goto fail;
	136	} else if (tmp != 0x100) {
	137	ret = -EINVAL;
16cdf7ce CH	138	goto fail;
	139	}
	140
69d34a36 KW	141	ret = read_uint32(bs, info_begin + 4, &count);
	142	if (ret < 0) {
	143	goto fail;
	144	} else if (count == 0) {
	145	ret = -EINVAL;
16cdf7ce CH	146	goto fail;
	147	}
	148	info_end = info_begin + count;
	149
	150	offset = info_begin + 0x100;
585d0ed9 FB	151
	152	/* read offsets */
	153	last_in_offset = last_out_offset = 0;
16cdf7ce	154	while (offset < info_end) {
995179f1 FB	155	uint32_t type;
995179f1 FB	156
69d34a36 KW	157	ret = read_uint32(bs, offset, &count);
	158	if (ret < 0) {
	159	goto fail;
	160	} else if (count == 0) {
	161	ret = -EINVAL;
	162	goto fail;
	163	}
16cdf7ce CH	164	offset += 4;
16cdf7ce CH	165
69d34a36 KW	166	ret = read_uint32(bs, offset, &type);
	167	if (ret < 0) {
	168	goto fail;
	169	}
	170
2c1885ad	171	if (type == 0x6d697368 && count >= 244) {
eb71803b SH	172	size_t new_size;
eb71803b SH	173	uint32_t chunk_count;
16cdf7ce CH	174
	175	offset += 4;
	176	offset += 200;
	177
2c1885ad SH	178	chunk_count = (count - 204) / 40;
	179	new_size = sizeof(uint64_t) * (s->n_chunks + chunk_count);
	180	s->types = g_realloc(s->types, new_size / 2);
	181	s->offsets = g_realloc(s->offsets, new_size);
	182	s->lengths = g_realloc(s->lengths, new_size);
	183	s->sectors = g_realloc(s->sectors, new_size);
	184	s->sectorcounts = g_realloc(s->sectorcounts, new_size);
585d0ed9	185
69d34a36 KW	186	for (i = s->n_chunks; i < s->n_chunks + chunk_count; i++) {
	187	ret = read_uint32(bs, offset, &s->types[i]);
	188	if (ret < 0) {
	189	goto fail;
	190	}
2c1885ad SH	191	offset += 4;
	192	if (s->types[i] != 0x80000005 && s->types[i] != 1 &&
	193	s->types[i] != 2) {
73ed27ec	194	if (s->types[i] == 0xffffffff && i > 0) {
2c1885ad SH	195	last_in_offset = s->offsets[i - 1] + s->lengths[i - 1];
	196	last_out_offset = s->sectors[i - 1] +
	197	s->sectorcounts[i - 1];
	198	}
	199	chunk_count--;
	200	i--;
	201	offset += 36;
	202	continue;
	203	}
	204	offset += 4;
16cdf7ce	205
69d34a36 KW	206	ret = read_uint64(bs, offset, &s->sectors[i]);
	207	if (ret < 0) {
	208	goto fail;
	209	}
	210	s->sectors[i] += last_out_offset;
	211	offset += 8;
16cdf7ce	212
69d34a36 KW	213	ret = read_uint64(bs, offset, &s->sectorcounts[i]);
	214	if (ret < 0) {
	215	goto fail;
	216	}
	217	offset += 8;
16cdf7ce	218
c165f775 SH	219	if (s->sectorcounts[i] > DMG_SECTORCOUNTS_MAX) {
	220	error_report("sector count %" PRIu64 " for chunk %u is "
	221	"larger than max (%u)",
	222	s->sectorcounts[i], i, DMG_SECTORCOUNTS_MAX);
	223	ret = -EINVAL;
	224	goto fail;
	225	}
	226
69d34a36 KW	227	ret = read_uint64(bs, offset, &s->offsets[i]);
	228	if (ret < 0) {
	229	goto fail;
	230	}
	231	s->offsets[i] += last_in_offset;
	232	offset += 8;
16cdf7ce	233
69d34a36 KW	234	ret = read_uint64(bs, offset, &s->lengths[i]);
	235	if (ret < 0) {
	236	goto fail;
	237	}
	238	offset += 8;
16cdf7ce	239
c165f775 SH	240	if (s->lengths[i] > DMG_LENGTHS_MAX) {
	241	error_report("length %" PRIu64 " for chunk %u is larger "
	242	"than max (%u)",
	243	s->lengths[i], i, DMG_LENGTHS_MAX);
	244	ret = -EINVAL;
	245	goto fail;
	246	}
	247
2c1885ad SH	248	if (s->lengths[i] > max_compressed_size) {
	249	max_compressed_size = s->lengths[i];
	250	}
	251	if (s->sectorcounts[i] > max_sectors_per_chunk) {
	252	max_sectors_per_chunk = s->sectorcounts[i];
	253	}
	254	}
	255	s->n_chunks += chunk_count;
	256	}
585d0ed9 FB	257	}
	258
	259	/* initialize zlib engine */
2c1885ad SH	260	s->compressed_chunk = g_malloc(max_compressed_size + 1);
	261	s->uncompressed_chunk = g_malloc(512 * max_sectors_per_chunk);
	262	if (inflateInit(&s->zstream) != Z_OK) {
69d34a36 KW	263	ret = -EINVAL;
	264	goto fail;
	265	}
585d0ed9 FB	266
585d0ed9 FB	267	s->current_chunk = s->n_chunks;
3b46e624	268
848c66e8	269	qemu_co_mutex_init(&s->lock);
585d0ed9	270	return 0;
69d34a36	271
1559ca00	272	fail:
69d34a36 KW	273	g_free(s->types);
	274	g_free(s->offsets);
	275	g_free(s->lengths);
	276	g_free(s->sectors);
	277	g_free(s->sectorcounts);
	278	g_free(s->compressed_chunk);
	279	g_free(s->uncompressed_chunk);
	280	return ret;
585d0ed9 FB	281	}
	282
	283	static inline int is_sector_in_chunk(BDRVDMGState* s,
2c1885ad	284	uint32_t chunk_num, int sector_num)
585d0ed9	285	{
2c1885ad SH	286	if (chunk_num >= s->n_chunks \|\| s->sectors[chunk_num] > sector_num \|\|
	287	s->sectors[chunk_num] + s->sectorcounts[chunk_num] <= sector_num) {
	288	return 0;
	289	} else {
	290	return -1;
	291	}
585d0ed9 FB	292	}
585d0ed9 FB	293
2c1885ad	294	static inline uint32_t search_chunk(BDRVDMGState *s, int sector_num)
585d0ed9 FB	295	{
585d0ed9 FB	296	/* binary search */
2c1885ad SH	297	uint32_t chunk1 = 0, chunk2 = s->n_chunks, chunk3;
	298	while (chunk1 != chunk2) {
	299	chunk3 = (chunk1 + chunk2) / 2;
	300	if (s->sectors[chunk3] > sector_num) {
	301	chunk2 = chunk3;
	302	} else if (s->sectors[chunk3] + s->sectorcounts[chunk3] > sector_num) {
	303	return chunk3;
	304	} else {
	305	chunk1 = chunk3;
	306	}
585d0ed9 FB	307	}
	308	return s->n_chunks; /* error */
	309	}
	310
64a31d5c	311	static inline int dmg_read_chunk(BlockDriverState *bs, int sector_num)
585d0ed9	312	{
64a31d5c CH	313	BDRVDMGState *s = bs->opaque;
64a31d5c CH	314
2c1885ad SH	315	if (!is_sector_in_chunk(s, s->current_chunk, sector_num)) {
	316	int ret;
	317	uint32_t chunk = search_chunk(s, sector_num);
585d0ed9	318
2c1885ad SH	319	if (chunk >= s->n_chunks) {
	320	return -1;
	321	}
585d0ed9	322
2c1885ad SH	323	s->current_chunk = s->n_chunks;
	324	switch (s->types[chunk]) {
	325	case 0x80000005: { /* zlib compressed */
2c1885ad SH	326	/* we need to buffer, because only the chunk as whole can be
2c1885ad SH	327	* inflated. */
b404bf85 SH	328	ret = bdrv_pread(bs->file, s->offsets[chunk],
b404bf85 SH	329	s->compressed_chunk, s->lengths[chunk]);
2c1885ad SH	330	if (ret != s->lengths[chunk]) {
	331	return -1;
	332	}
	333
	334	s->zstream.next_in = s->compressed_chunk;
	335	s->zstream.avail_in = s->lengths[chunk];
	336	s->zstream.next_out = s->uncompressed_chunk;
	337	s->zstream.avail_out = 512 * s->sectorcounts[chunk];
	338	ret = inflateReset(&s->zstream);
	339	if (ret != Z_OK) {
	340	return -1;
	341	}
	342	ret = inflate(&s->zstream, Z_FINISH);
	343	if (ret != Z_STREAM_END \|\|
	344	s->zstream.total_out != 512 * s->sectorcounts[chunk]) {
	345	return -1;
	346	}
	347	break; }
	348	case 1: /* copy */
	349	ret = bdrv_pread(bs->file, s->offsets[chunk],
64a31d5c	350	s->uncompressed_chunk, s->lengths[chunk]);
2c1885ad SH	351	if (ret != s->lengths[chunk]) {
	352	return -1;
	353	}
	354	break;
	355	case 2: /* zero */
	356	memset(s->uncompressed_chunk, 0, 512 * s->sectorcounts[chunk]);
	357	break;
	358	}
	359	s->current_chunk = chunk;
585d0ed9 FB	360	}
	361	return 0;
	362	}
	363
5fafdf24	364	static int dmg_read(BlockDriverState *bs, int64_t sector_num,
585d0ed9 FB	365	uint8_t *buf, int nb_sectors)
	366	{
	367	BDRVDMGState *s = bs->opaque;
	368	int i;
	369
2c1885ad SH	370	for (i = 0; i < nb_sectors; i++) {
	371	uint32_t sector_offset_in_chunk;
	372	if (dmg_read_chunk(bs, sector_num + i) != 0) {
	373	return -1;
	374	}
	375	sector_offset_in_chunk = sector_num + i - s->sectors[s->current_chunk];
	376	memcpy(buf + i * 512,
	377	s->uncompressed_chunk + sector_offset_in_chunk * 512, 512);
585d0ed9 FB	378	}
	379	return 0;
	380	}
	381
2914caa0 PB	382	static coroutine_fn int dmg_co_read(BlockDriverState *bs, int64_t sector_num,
	383	uint8_t *buf, int nb_sectors)
	384	{
	385	int ret;
	386	BDRVDMGState *s = bs->opaque;
	387	qemu_co_mutex_lock(&s->lock);
	388	ret = dmg_read(bs, sector_num, buf, nb_sectors);
	389	qemu_co_mutex_unlock(&s->lock);
	390	return ret;
	391	}
	392
585d0ed9 FB	393	static void dmg_close(BlockDriverState *bs)
	394	{
	395	BDRVDMGState *s = bs->opaque;
4f8aa2e1 KW	396
	397	g_free(s->types);
	398	g_free(s->offsets);
	399	g_free(s->lengths);
	400	g_free(s->sectors);
	401	g_free(s->sectorcounts);
	402	g_free(s->compressed_chunk);
	403	g_free(s->uncompressed_chunk);
	404
585d0ed9 FB	405	inflateEnd(&s->zstream);
	406	}
	407
5efa9d5a	408	static BlockDriver bdrv_dmg = {
2c1885ad SH	409	.format_name = "dmg",
	410	.instance_size = sizeof(BDRVDMGState),
	411	.bdrv_probe = dmg_probe,
	412	.bdrv_open = dmg_open,
	413	.bdrv_read = dmg_co_read,
	414	.bdrv_close = dmg_close,
585d0ed9	415	};
5efa9d5a AL	416
	417	static void bdrv_dmg_init(void)
	418	{
	419	bdrv_register(&bdrv_dmg);
	420	}
	421
	422	block_init(bdrv_dmg_init);