1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
|
/*
* This file has been modified for the cdrkit suite.
*
* The behaviour and appearence of the program code below can differ to a major
* extent from the version distributed by the original author(s).
*
* For details, see Changelog file distributed with the cdrkit package. If you
* received this file from another source then ask the distributing person for
* a log of modifications.
*
*/
/* $Id: uncompress.c,v 1.3 2006/07/04 04:57:42 hpa Exp $ */
/* ----------------------------------------------------------------------- *
*
* Copyright 2001-2006 H. Peter Anvin - All Rights Reserved
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, Inc., 675 Mass Ave, Cambridge MA 02139,
* USA; either version 2 of the License, or (at your option) any later
* version; incorporated herein by reference.
*
* ----------------------------------------------------------------------- */
#include "mkzftree.h" /* Must be included first! */
#include <stdio.h>
#include <stdlib.h>
#include <zlib.h>
#include "iso9660.h"
int block_uncompress_file(FILE *input, FILE *output, off_t size)
{
struct compressed_file_header hdr;
Bytef *inbuf, *outbuf;
int block_shift;
char *pointer_block, *pptr;
unsigned long nblocks;
unsigned long fullsize, block_size, block_size2;
size_t ptrblock_bytes;
unsigned long cstart, cend, csize;
uLong bytes;
int zerr;
int err = EX_SOFTWARE;
if ( (bytes = fread(&hdr, 1, sizeof hdr, input)) != sizeof hdr ) {
if ( bytes == (size_t)size ) {
/* Very short file; not compressed */
return ( fwrite(&hdr, 1, bytes, output) != bytes ) ? EX_CANTCREAT : 0;
} else {
return EX_IOERR; /* Read error */
}
}
if ( memcmp(&hdr.magic, zisofs_magic, sizeof zisofs_magic) ) {
inbuf = xmalloc(CBLOCK_SIZE);
/* Not compressed */
memcpy(inbuf, &hdr, sizeof hdr);
bytes = sizeof hdr;
do {
if ( fwrite(inbuf, 1, bytes, output) != bytes )
return EX_CANTCREAT;
} while ( (bytes = fread(inbuf, 1, CBLOCK_SIZE, input)) > 0 );
free(inbuf);
return ferror(input) ? EX_IOERR : 0;
}
/* Now we know the file must be compressed. Get the pointer table. */
if ( fseek(input, hdr.header_size << 2, SEEK_SET) == -1 )
return EX_IOERR;
fullsize = get_731(hdr.uncompressed_len);
block_shift = hdr.block_size;
block_size = 1UL << block_shift;
block_size2 = block_size << 1;
inbuf = xmalloc(block_size2);
outbuf = xmalloc(block_size);
nblocks = (fullsize + block_size - 1) >> block_shift;
ptrblock_bytes = (nblocks+1) * 4;
pointer_block = xmalloc(ptrblock_bytes);
if ( (bytes = fread(pointer_block, 1, ptrblock_bytes, input)) != ptrblock_bytes ) {
err = EX_IOERR;
goto free_ptr_bail;
}
pptr = pointer_block;
while ( fullsize ) {
cstart = get_731(pptr);
pptr += 4;
cend = get_731(pptr);
csize = cend-cstart;
if ( csize == 0 ) {
memset(outbuf, 0, block_size);
bytes = block_size;
} else {
if ( csize > block_size2 ) {
err = EX_DATAERR;
goto free_ptr_bail;
}
if ( fseek(input, cstart, SEEK_SET) == -1 ||
(bytes = fread(inbuf, 1, csize, input)) != csize ) {
err = EX_IOERR;
goto free_ptr_bail;
}
bytes = block_size; /* Max output buffer size */
if ( (zerr = uncompress(outbuf, &bytes, inbuf, csize)) != Z_OK ) {
err = (zerr = Z_MEM_ERROR) ? EX_OSERR : EX_DATAERR;
goto free_ptr_bail;
}
}
if ( ((fullsize > block_size) && (bytes != block_size))
|| ((fullsize <= block_size) && (bytes < fullsize)) ) {
err = EX_DATAERR;
goto free_ptr_bail;
}
if ( bytes > fullsize )
bytes = fullsize;
if ( fwrite(outbuf, 1, bytes, output) != bytes ) {
err = EX_CANTCREAT;
goto free_ptr_bail;
}
fullsize -= bytes;
}
err = 0;
free_ptr_bail:
free(pointer_block);
free(inbuf);
free(outbuf);
return err;
}
|
