/*
* 2ooM: The Master of Orion II Reverse Engineering Project
* Library for working with LBX archive files.
* Copyright © 2006-2010, 2013-2014 Nick Bowler
*
* 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, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see .
*/
#include
#include
#include
#include
#include
#include
#include "pack.h"
#include "misc.h"
#include "error.h"
#include "lbx.h"
#define LBX_MAGIC 0x0000fead
#define LBX_HDR_SIZE 8
struct lbx_priv {
struct lbx pub;
char *name;
const struct lbx_file_ops *fops;
int (*dtor)(void *handle);
void *f;
struct lbx_file_state *last_file;
unsigned long offsets[];
};
struct lbx_file_state {
unsigned long base, limit, offset;
struct lbx_priv *lbx;
int eof;
};
static struct lbx_priv *lbx_init(unsigned char *hdr)
{
unsigned short nfiles = unpack_16_le(hdr+0);
unsigned long magic = unpack_32_le(hdr+2);
unsigned short version = unpack_16_le(hdr+6);
struct lbx_priv *lbx;
if (magic != LBX_MAGIC) {
lbx_error_raise(LBX_EMAGIC);
return NULL;
}
lbx = malloc(sizeof *lbx + sizeof lbx->offsets[0] * (nfiles+1));
if (!lbx) {
lbx_error_raise(LBX_ENOMEM);
return NULL;
}
*lbx = (struct lbx_priv) {
.pub = { .nfiles = nfiles, },
};
return lbx;
}
static char *str_dup(const char *s)
{
char *buf;
buf = malloc(strlen(s)+1);
if (buf)
strcpy(buf, s);
return buf;
}
struct lbx *lbx_open(void *f, const struct lbx_file_ops *fops,
int (*destructor)(void *), const char *name)
{
unsigned char hdr_buf[LBX_HDR_SIZE];
struct lbx_priv *lbx = NULL;
char *dupname = NULL;
dupname = str_dup(name);
if (!dupname) {
lbx_error_raise(LBX_ENOMEM);
goto err;
}
if (fops->read(hdr_buf, sizeof hdr_buf, f) != sizeof hdr_buf) {
if (fops->eof(f))
lbx_error_raise(LBX_EEOF);
goto err;
}
lbx = lbx_init(hdr_buf);
if (!lbx)
goto err;
lbx->name = dupname;
lbx->dtor = destructor;
lbx->fops = fops;
lbx->f = f;
for (unsigned i = 0; i <= lbx->pub.nfiles; i++) {
unsigned char buf[4];
if (fops->read(buf, sizeof buf, f) != sizeof buf) {
if (fops->eof(f))
lbx_error_raise(LBX_EEOF);
goto err;
}
lbx->offsets[i] = unpack_32_le(buf);
}
return &lbx->pub;
err:
free(dupname);
free(lbx);
return NULL;
}
static int file_close(void *f)
{
return fclose((FILE *)f);
}
static int pipe_close(void *f)
{
struct lbx_pipe_state *p = f;
int rc;
rc = fclose(p->f);
free(p);
return rc;
}
static char *last_component(const char *name)
{
char *c;
/* TODO: Handle other path separators. */
c = strrchr(name, '/');
if (!c)
return (char *)name;
return c+1;
}
struct lbx *lbx_fopen(const char *file)
{
const char *name = last_component(file);
struct lbx_pipe_state *p;
FILE *f;
f = fopen(file, "rb");
if (!f) {
lbx_error_raise(-errno);
return NULL;
}
if (fseek(f, 0, SEEK_CUR) == 0)
return lbx_open(f, &lbx_default_fops, file_close, name);
p = malloc(sizeof *p);
if (!p) {
lbx_error_raise(LBX_ENOMEM);
fclose(f);
return NULL;
}
*p = (struct lbx_pipe_state) { .f = f };
return lbx_open(p, &lbx_pipe_fops, pipe_close, name);
}
int lbx_file_stat(struct lbx *pub, unsigned fileno, struct lbx_statbuf *buf)
{
struct lbx_priv *lbx = (struct lbx_priv *)pub;
static char str[256]; /* FIXME */
if (fileno >= lbx->pub.nfiles) {
lbx_error_raise(LBX_EINVAL);
buf->name = NULL;
return -1;
}
snprintf(str, sizeof str, "%s.%03u", lbx->name, fileno);
buf->name = str;
buf->size = lbx->offsets[fileno+1] - lbx->offsets[fileno];
return 0;
}
int lbx_close(struct lbx *pub)
{
struct lbx_priv *lbx = (struct lbx_priv *)pub;
int rc = 0;
if (lbx && lbx->dtor)
rc = lbx->dtor(lbx->f);
free(lbx->name);
free(lbx);
return rc;
}
struct lbx_file_state *lbx_file_open(struct lbx *pub, unsigned fileno)
{
struct lbx_priv *lbx = (struct lbx_priv *)pub;
struct lbx_file_state *state;
if (fileno >= lbx->pub.nfiles) {
lbx_error_raise(LBX_EINVAL);
return NULL;
}
lbx->last_file = NULL;
if (lbx->fops->seek(lbx->f, lbx->offsets[fileno], SEEK_SET) != 0) {
return NULL;
}
state = malloc(sizeof *state);
if (!state) {
lbx_error_raise(LBX_ENOMEM);
return NULL;
}
*state = (struct lbx_file_state) {
.base = lbx->offsets[fileno],
.limit = lbx->offsets[fileno+1] - lbx->offsets[fileno],
.lbx = lbx,
};
lbx->last_file = state;
return state;
}
size_t lbx_file_read(struct lbx_file_state *f, void *buf, size_t n)
{
const struct lbx_file_ops *fops = f->lbx->fops;
size_t want = MIN(n, f->limit - f->offset);
size_t rc;
if (f != f->lbx->last_file) {
f->lbx->last_file = NULL;
if (fops->seek(f->lbx->f, f->base + f->limit, SEEK_SET) != 0)
return 0;
f->lbx->last_file = f;
}
rc = fops->read(buf, want, f->lbx->f);
f->offset += rc;
if (rc < want) {
if (fops->eof(f->lbx->f))
lbx_error_raise(LBX_EEOF);
} else if (rc < n) {
f->eof = 1;
}
return rc;
}
int lbx_file_seek(struct lbx_file_state *f, long offset, int whence)
{
const struct lbx_file_ops *fops = f->lbx->fops;
unsigned long pos;
switch (whence) {
case SEEK_CUR:
pos = f->offset + offset;
break;
case SEEK_SET:
pos = offset;
break;
case SEEK_END:
pos = f->limit + offset;
break;
default:
lbx_error_raise(LBX_EINVAL);
return -1;
}
if (pos > f->limit) {
lbx_error_raise(LBX_EINVAL);
return -1;
}
f->lbx->last_file = NULL;
if (fops->seek(f->lbx->f, f->base + pos, SEEK_SET) != 0)
return -1;
f->offset = pos;
f->lbx->last_file = f;
f->eof = 0;
return 0;
}
long lbx_file_tell(struct lbx_file_state *f)
{
return f->offset;
}
int lbx_file_eof(struct lbx_file_state *f)
{
return f->eof;
}
void lbx_file_close(struct lbx_file_state *f)
{
if (f->lbx->last_file == f)
f->lbx->last_file = NULL;
free(f);
}