2 * 2ooM: The Master of Orion II Reverse Engineering Project
3 * Library for working with LBX archive files.
4 * Copyright (C) 2006-2008 Nick Bowler
6 * This program is free software: you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation, either version 3 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program. If not, see <http://www.gnu.org/licenses/>.
33 #define LBX_MAGIC 0x0000fead
34 #define LBX_HDR_SIZE 8
41 const struct lbx_file_ops *fops;
42 int (*dtor)(void *handle);
45 struct lbx_file_state *last_file;
47 unsigned short nfiles;
48 unsigned long offsets[];
51 struct lbx_file_state {
52 unsigned long base, limit, offset;
53 struct lbx_state *lbx;
57 static struct lbx_state *lbx_init(unsigned char hdr[static LBX_HDR_SIZE])
59 unsigned short nfiles = unpack_16_le(hdr+0);
60 unsigned long magic = unpack_32_le(hdr+2);
61 unsigned short version = unpack_16_le(hdr+6);
62 struct lbx_state *lbx;
64 if (magic != LBX_MAGIC) {
65 lbx_errno = -LBX_EMAGIC;
69 lbx = malloc(sizeof *lbx + sizeof lbx->offsets[0] * (nfiles+1));
75 *lbx = (struct lbx_state) {
82 static char *str_dup(const char *s)
86 buf = malloc(strlen(s)+1);
92 struct lbx_state *lbx_open(void *f, const struct lbx_file_ops *fops,
93 int (*destructor)(void *), const char *name)
95 unsigned char hdr_buf[LBX_HDR_SIZE];
96 struct lbx_state *lbx = NULL;
99 dupname = str_dup(name);
105 if (fops->read(hdr_buf, sizeof hdr_buf, f) != sizeof hdr_buf) {
110 lbx = lbx_init(hdr_buf);
115 lbx->dtor = destructor;
119 for (unsigned i = 0; i <= lbx->nfiles; i++) {
120 unsigned char buf[4];
122 if (fops->read(buf, sizeof buf, f) != sizeof buf) {
125 lbx_errno = LBX_EEOF;
129 lbx->offsets[i] = unpack_32_le(buf);
139 struct lbx_state *lbx_fopen(FILE *f, const char *name)
141 return lbx_open(f, &lbx_default_fops, NULL, name);
144 size_t lbx_numfiles(struct lbx_state *lbx)
149 int lbx_stat(struct lbx_state *lbx, size_t index, struct lbx_statbuf *buf)
151 static char str[256]; /* FIXME */
153 if (index >= lbx->nfiles) {
155 lbx_errno = LBX_ERANGE;
159 snprintf(str, sizeof str, "%s.%03zu", lbx->name, index);
161 buf->size = lbx->offsets[index+1] - lbx->offsets[index];
165 int lbx_close(struct lbx_state *lbx)
169 if (lbx && lbx->dtor)
170 rc = lbx->dtor(lbx->f);
177 struct lbx_file_state *lbx_file_open(struct lbx_state *lbx, unsigned fileno)
179 struct lbx_file_state *state;
181 if (fileno >= lbx->nfiles) {
182 lbx_errno = LBX_ERANGE;
186 lbx->last_file = NULL;
187 if (lbx->fops->seek(lbx->f, lbx->offsets[fileno], SEEK_SET) != 0) {
192 state = malloc(sizeof *state);
198 *state = (struct lbx_file_state) {
199 .base = lbx->offsets[fileno],
200 .limit = lbx->offsets[fileno+1] - lbx->offsets[fileno],
204 lbx->last_file = state;
208 size_t lbx_file_read(struct lbx_file_state *f, void *buf, size_t n)
210 const struct lbx_file_ops *fops = f->lbx->fops;
211 size_t want = MIN(n, f->limit - f->offset);
214 if (f != f->lbx->last_file) {
215 f->lbx->last_file = NULL;
216 if (fops->seek(f->lbx->f, f->base + f->limit, SEEK_SET) != 0)
218 f->lbx->last_file = f;
221 rc = fops->read(buf, want, f->lbx->f);
224 if (want < n || (rc < want && fops->eof(f->lbx->f)))
229 int lbx_file_seek(struct lbx_file_state *f, long offset, int whence)
231 const struct lbx_file_ops *fops = f->lbx->fops;
236 pos = f->offset + offset;
242 pos = f->limit + offset;
249 f->lbx->last_file = NULL;
250 if (fops->seek(f->lbx->f, f->base + pos, SEEK_SET) != 0)
252 f->lbx->last_file = f;
258 long lbx_file_tell(struct lbx_file_state *f)
263 int lbx_file_eof(struct lbx_file_state *f)
268 void lbx_file_close(struct lbx_file_state *f)
270 if (f->lbx->last_file == f)
271 f->lbx->last_file = NULL;
275 const char *lbx_strerror(void)
278 return strerror(-lbx_errno);
281 case LBX_ESUCCESS: return "Success";
282 case LBX_EMAGIC: return "Bad magic number";
283 case LBX_EEOF: return "Unexpected end-of-file";
284 case LBX_ERANGE: return "Index out of range";
285 case LBX_EFORMAT: return "Invalid file format";
288 return "Unknown error";