/
physfs_archiver_hog.c
170 lines (144 loc) · 5.04 KB
/
physfs_archiver_hog.c
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
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
/*
* HOG support routines for PhysicsFS.
*
* This driver handles Descent I/II/III HOG archives.
*
* The Descent I/II format is very simple:
*
* The file always starts with the 3-byte signature "DHF" (Descent
* HOG file). After that the files of a HOG are just attached after
* another, divided by a 17 bytes header, which specifies the name
* and length (in bytes) of the forthcoming file! So you just read
* the header with its information of how big the following file is,
* and then skip exact that number of bytes to get to the next file
* in that HOG.
*
* char sig[3] = {'D', 'H', 'F'}; // "DHF"=Descent HOG File
*
* struct {
* char file_name[13]; // Filename, padded to 13 bytes with 0s
* int file_size; // filesize in bytes
* char data[file_size]; // The file data
* } FILE_STRUCT; // Repeated until the end of the file.
*
* (That info is from http://www.descent2.com/ddn/specs/hog/)
*
* Descent 3 moved to HOG2 format, which starts with the chars "HOG2",
* then 32-bits for the number of contained files, 32 bits for the offset
* to the first file's data, then 56 bytes of 0xFF (reserved?). Then for
* each file, there's 36 bytes for filename (null-terminated, rest of bytes
* are garbage), 32-bits unknown/reserved (always zero?), 32-bits of length
* of file data, 32-bits of time since Unix epoch. Then immediately following,
* for each file is their uncompressed content, you can find its offset
* by starting at the initial data offset and adding the filesize of each
* prior file.
*
* This information was found at:
* https://web.archive.org/web/20020213004051/http://descent-3.com/ddn/specs/hog/
*
*
* Please see the file LICENSE.txt in the source's root directory.
*
* This file written by Bradley Bell and Ryan C. Gordon.
*/
#define __PHYSICSFS_INTERNAL__
#include "physfs_internal.h"
#if PHYSFS_SUPPORTS_HOG
static int readui32(PHYSFS_Io *io, PHYSFS_uint32 *val)
{
PHYSFS_uint32 v;
BAIL_IF_ERRPASS(!__PHYSFS_readAll(io, &v, sizeof (v)), 0);
*val = PHYSFS_swapULE32(v);
return 1;
} /* readui32 */
static int hog1LoadEntries(PHYSFS_Io *io, void *arc)
{
const PHYSFS_uint64 iolen = io->length(io);
PHYSFS_uint32 pos = 3;
while (pos < iolen)
{
PHYSFS_uint32 size;
char name[13];
BAIL_IF_ERRPASS(!__PHYSFS_readAll(io, name, 13), 0);
BAIL_IF_ERRPASS(!readui32(io, &size), 0);
name[12] = '\0'; /* just in case. */
pos += 13 + 4;
BAIL_IF_ERRPASS(!UNPK_addEntry(arc, name, 0, -1, -1, pos, size), 0);
pos += size;
/* skip over entry */
BAIL_IF_ERRPASS(!io->seek(io, pos), 0);
} /* while */
return 1;
} /* hogLoadEntries */
static int hog2LoadEntries(PHYSFS_Io *io, void *arc)
{
PHYSFS_uint32 numfiles;
PHYSFS_uint32 pos;
PHYSFS_uint32 i;
BAIL_IF_ERRPASS(!readui32(io, &numfiles), 0);
BAIL_IF_ERRPASS(!readui32(io, &pos), 0);
BAIL_IF_ERRPASS(!io->seek(io, 68), 0); /* skip to end of header. */
for (i = 0; i < numfiles; i++) {
char name[37];
PHYSFS_uint32 reserved;
PHYSFS_uint32 size;
PHYSFS_uint32 mtime;
BAIL_IF_ERRPASS(!__PHYSFS_readAll(io, name, 36), 0);
BAIL_IF_ERRPASS(!readui32(io, &reserved), 0);
BAIL_IF_ERRPASS(!readui32(io, &size), 0);
BAIL_IF_ERRPASS(!readui32(io, &mtime), 0);
name[36] = '\0'; /* just in case */
BAIL_IF_ERRPASS(!UNPK_addEntry(arc, name, 0, mtime, mtime, pos, size), 0);
pos += size;
}
return 1;
} /* hog2LoadEntries */
static void *HOG_openArchive(PHYSFS_Io *io, const char *name,
int forWriting, int *claimed)
{
PHYSFS_uint8 buf[3];
void *unpkarc = NULL;
int hog1 = 0;
assert(io != NULL); /* shouldn't ever happen. */
BAIL_IF(forWriting, PHYSFS_ERR_READ_ONLY, NULL);
BAIL_IF_ERRPASS(!__PHYSFS_readAll(io, buf, 3), NULL);
if (memcmp(buf, "DHF", 3) == 0)
hog1 = 1; /* original HOG (Descent 1 and 2) archive */
else
{
BAIL_IF(memcmp(buf, "HOG", 3) != 0, PHYSFS_ERR_UNSUPPORTED, NULL); /* Not HOG2 */
BAIL_IF_ERRPASS(!__PHYSFS_readAll(io, buf, 1), NULL);
BAIL_IF(buf[0] != '2', PHYSFS_ERR_UNSUPPORTED, NULL); /* Not HOG2 */
} /* else */
*claimed = 1;
unpkarc = UNPK_openArchive(io);
BAIL_IF_ERRPASS(!unpkarc, NULL);
if (!(hog1 ? hog1LoadEntries(io, unpkarc) : hog2LoadEntries(io, unpkarc)))
{
UNPK_abandonArchive(unpkarc);
return NULL;
} /* if */
return unpkarc;
} /* HOG_openArchive */
const PHYSFS_Archiver __PHYSFS_Archiver_HOG =
{
CURRENT_PHYSFS_ARCHIVER_API_VERSION,
{
"HOG",
"Descent I/II/III HOG file format",
"Bradley Bell <btb@icculus.org>",
"https://icculus.org/physfs/",
0, /* supportsSymlinks */
},
HOG_openArchive,
UNPK_enumerate,
UNPK_openRead,
UNPK_openWrite,
UNPK_openAppend,
UNPK_remove,
UNPK_mkdir,
UNPK_stat,
UNPK_closeArchive
};
#endif /* defined PHYSFS_SUPPORTS_HOG */
/* end of physfs_archiver_hog.c ... */