xenia-canary/third_party/mspack/system.c

243 lines
6.2 KiB
C

/* This file is part of libmspack.
* (C) 2003-2004 Stuart Caie.
*
* libmspack is free software; you can redistribute it and/or modify it under
* the terms of the GNU Lesser General Public License (LGPL) version 2.1
*
* For further details, see the file COPYING.LIB distributed with libmspack
*/
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#include <system.h>
#if !LARGEFILE_SUPPORT
const char *largefile_msg = "library not compiled to support large files.";
#endif
int mspack_version(int entity) {
switch (entity) {
/* CHM decoder version 1 -> 2 changes:
* - added mschmd_sec_mscompressed::spaninfo
* - added mschmd_header::first_pmgl
* - added mschmd_header::last_pmgl
* - added mschmd_header::chunk_cache;
*/
case MSPACK_VER_MSCHMD:
/* CAB decoder version 1 -> 2 changes:
* - added MSCABD_PARAM_SALVAGE
*/
case MSPACK_VER_MSCABD:
return 2;
case MSPACK_VER_LIBRARY:
case MSPACK_VER_SYSTEM:
case MSPACK_VER_MSSZDDD:
case MSPACK_VER_MSKWAJD:
case MSPACK_VER_MSOABD:
return 1;
case MSPACK_VER_MSCABC:
case MSPACK_VER_MSCHMC:
case MSPACK_VER_MSLITD:
case MSPACK_VER_MSLITC:
case MSPACK_VER_MSHLPD:
case MSPACK_VER_MSHLPC:
case MSPACK_VER_MSSZDDC:
case MSPACK_VER_MSKWAJC:
case MSPACK_VER_MSOABC:
return 0;
}
return -1;
}
int mspack_sys_selftest_internal(int offt_size) {
return (sizeof(off_t) == offt_size) ? MSPACK_ERR_OK : MSPACK_ERR_SEEK;
}
/* validates a system structure */
int mspack_valid_system(struct mspack_system *sys) {
return (sys != NULL) && (sys->open != NULL) && (sys->close != NULL) &&
(sys->read != NULL) && (sys->write != NULL) && (sys->seek != NULL) &&
(sys->tell != NULL) && (sys->message != NULL) && (sys->alloc != NULL) &&
(sys->free != NULL) && (sys->copy != NULL) && (sys->null_ptr == NULL);
}
/* returns the length of a file opened for reading */
int mspack_sys_filelen(struct mspack_system *system,
struct mspack_file *file, off_t *length)
{
off_t current;
if (!system || !file || !length) return MSPACK_ERR_OPEN;
/* get current offset */
current = system->tell(file);
/* seek to end of file */
if (system->seek(file, (off_t) 0, MSPACK_SYS_SEEK_END)) {
return MSPACK_ERR_SEEK;
}
/* get offset of end of file */
*length = system->tell(file);
/* seek back to original offset */
if (system->seek(file, current, MSPACK_SYS_SEEK_START)) {
return MSPACK_ERR_SEEK;
}
return MSPACK_ERR_OK;
}
/* definition of mspack_default_system -- if the library is compiled with
* MSPACK_NO_DEFAULT_SYSTEM, no default system will be provided. Otherwise,
* an appropriate default system (e.g. the standard C library, or some native
* API calls)
*/
#ifdef MSPACK_NO_DEFAULT_SYSTEM
struct mspack_system *mspack_default_system = NULL;
#else
/* implementation of mspack_default_system for standard C library */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
struct mspack_file_p {
FILE *fh;
const char *name;
};
static struct mspack_file *msp_open(struct mspack_system *self,
const char *filename, int mode)
{
struct mspack_file_p *fh;
const char *fmode;
switch (mode) {
case MSPACK_SYS_OPEN_READ: fmode = "rb"; break;
case MSPACK_SYS_OPEN_WRITE: fmode = "wb"; break;
case MSPACK_SYS_OPEN_UPDATE: fmode = "r+b"; break;
case MSPACK_SYS_OPEN_APPEND: fmode = "ab"; break;
default: return NULL;
}
if ((fh = (struct mspack_file_p *) malloc(sizeof(struct mspack_file_p)))) {
fh->name = filename;
if ((fh->fh = fopen(filename, fmode))) return (struct mspack_file *) fh;
free(fh);
}
return NULL;
}
static void msp_close(struct mspack_file *file) {
struct mspack_file_p *self = (struct mspack_file_p *) file;
if (self) {
fclose(self->fh);
free(self);
}
}
static int msp_read(struct mspack_file *file, void *buffer, int bytes) {
struct mspack_file_p *self = (struct mspack_file_p *) file;
if (self && buffer && bytes >= 0) {
size_t count = fread(buffer, 1, (size_t) bytes, self->fh);
if (!ferror(self->fh)) return (int) count;
}
return -1;
}
static int msp_write(struct mspack_file *file, void *buffer, int bytes) {
struct mspack_file_p *self = (struct mspack_file_p *) file;
if (self && buffer && bytes >= 0) {
size_t count = fwrite(buffer, 1, (size_t) bytes, self->fh);
if (!ferror(self->fh)) return (int) count;
}
return -1;
}
static int msp_seek(struct mspack_file *file, off_t offset, int mode) {
struct mspack_file_p *self = (struct mspack_file_p *) file;
if (self) {
switch (mode) {
case MSPACK_SYS_SEEK_START: mode = SEEK_SET; break;
case MSPACK_SYS_SEEK_CUR: mode = SEEK_CUR; break;
case MSPACK_SYS_SEEK_END: mode = SEEK_END; break;
default: return -1;
}
#if HAVE_FSEEKO
return fseeko(self->fh, offset, mode);
#else
return fseek(self->fh, offset, mode);
#endif
}
return -1;
}
static off_t msp_tell(struct mspack_file *file) {
struct mspack_file_p *self = (struct mspack_file_p *) file;
#if HAVE_FSEEKO
return (self) ? (off_t) ftello(self->fh) : 0;
#else
return (self) ? (off_t) ftell(self->fh) : 0;
#endif
}
static void msp_msg(struct mspack_file *file, const char *format, ...) {
va_list ap;
if (file) fprintf(stderr, "%s: ", ((struct mspack_file_p *) file)->name);
va_start(ap, format);
vfprintf(stderr, format, ap);
va_end(ap);
fputc((int) '\n', stderr);
fflush(stderr);
}
static void *msp_alloc(struct mspack_system *self, size_t bytes) {
#if DEBUG
/* make uninitialised data obvious */
char *buf = malloc(bytes + 8);
if (buf) memset(buf, 0xDC, bytes);
*((size_t *)buf) = bytes;
return &buf[8];
#else
return malloc(bytes);
#endif
}
static void msp_free(void *buffer) {
#if DEBUG
char *buf = buffer;
size_t bytes;
if (buf) {
buf -= 8;
bytes = *((size_t *)buf);
/* make freed data obvious */
memset(buf, 0xED, bytes);
free(buf);
}
#else
free(buffer);
#endif
}
static void msp_copy(void *src, void *dest, size_t bytes) {
memcpy(dest, src, bytes);
}
static struct mspack_system msp_system = {
&msp_open, &msp_close, &msp_read, &msp_write, &msp_seek,
&msp_tell, &msp_msg, &msp_alloc, &msp_free, &msp_copy, NULL
};
struct mspack_system *mspack_default_system = &msp_system;
#endif