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April 23, 2019 13:13
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/*----------------------------------------------------------------------------*/ | |
/*-- blz.c - Bottom LZ coding for Nintendo GBA/DS --*/ | |
/*-- Copyright (C) 2011 CUE --*/ | |
/*-- --*/ | |
/*-- 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 <http://www.gnu.org/licenses/>. --*/ | |
/*----------------------------------------------------------------------------*/ | |
/*----------------------------------------------------------------------------*/ | |
#include "blz.h" | |
#include <stdlib.h> | |
#include <stdio.h> | |
#include <string.h> | |
/*----------------------------------------------------------------------------*/ | |
#define CMD_DECODE 0x00 // decode | |
#define CMD_ENCODE 0x01 // encode | |
#define BLZ_SHIFT 1 // bits to shift | |
#define BLZ_MASK 0x80 // bits to check: | |
// ((((1 << BLZ_SHIFT) - 1) << (8 - BLZ_SHIFT) | |
#define BLZ_THRESHOLD 2 // max number of bytes to not encode | |
#define BLZ_N 0x1002 // max offset ((1 << 12) + 2) | |
#define BLZ_F 0x12 // max coded ((1 << 4) + BLZ_THRESHOLD) | |
#define RAW_MINIM 0x00000000 // empty file, 0 bytes | |
#define RAW_MAXIM 0x00FFFFFF // 3-bytes length, 16MB - 1 | |
#define BLZ_MINIM 0x00000004 // header only (empty RAW file) | |
#define BLZ_MAXIM 0x01400000 // 0x0120000A, padded to 20MB: | |
// * length, RAW_MAXIM | |
// * flags, (RAW_MAXIM + 7) / 8 | |
// * header, 11 | |
// 0x00FFFFFF + 0x00200000 + 12 + padding | |
/*----------------------------------------------------------------------------*/ | |
#define BREAK(text) { printf(text); return; } | |
#define EXIT(text) { printf(text); exit(-1); } | |
/*----------------------------------------------------------------------------*/ | |
u8 *Memory(int length, int size); | |
u8 *BLZ_Code(u8 *raw_buffer, int raw_len, u32 *new_len, int best); | |
u8* BLZ_DecodeBuffer(u8 *pak_buffer, u32 pak_len, u32* unpak_len); | |
void BLZ_Invert(u8 *buffer, int length); | |
/*----------------------------------------------------------------------------*/ | |
u8 *Memory(int length, int size) { | |
u8 *fb; | |
fb = (u8 *) calloc(length * size, size); | |
if (fb == NULL) EXIT("\nMemory error\n"); | |
return(fb); | |
} | |
/*----------------------------------------------------------------------------*/ | |
u8 *Load(char *filename, u32 *length, int min, int max) { | |
FILE *fp; | |
int fs; | |
u8 *fb; | |
if ((fp = fopen(filename, "rb")) == NULL) EXIT("\nFile open error\n"); | |
fseek(fp, 0, SEEK_END); | |
fs = ftell(fp); | |
fseek(fp, 0, SEEK_SET); | |
if ((fs < min) || (fs > max)) EXIT("\nFile size error\n"); | |
fb = Memory(fs + 3, sizeof(char)); | |
if (fread(fb, 1, fs, fp) != fs) EXIT("\nFile read error\n"); | |
if (fclose(fp) == EOF) EXIT("\nFile close error\n"); | |
*length = fs; | |
return(fb); | |
} | |
/*----------------------------------------------------------------------------*/ | |
u8* BLZ_Decode(char *filename, u32* unpak_len){ | |
u8 *raw_buffer, *pak_buffer, *new_buffer; | |
u32 raw_len, new_len; | |
raw_buffer = Load(filename, &raw_len, RAW_MINIM, RAW_MAXIM); | |
new_buffer = BLZ_DecodeBuffer(raw_buffer, raw_len, &new_len); | |
pak_buffer = new_buffer; | |
*unpak_len = new_len; | |
return pak_buffer; | |
} | |
/*----------------------------------------------------------------------------*/ | |
u8* BLZ_DecodeBuffer(u8 *pak_buffer, u32 pak_len, u32* unpak_len) { | |
unsigned char *end_pak_buffer, *raw_buffer, *pak, *raw, *pak_end, *raw_end; | |
unsigned int raw_len, len, pos, inc_len, hdr_len, enc_len, dec_len; | |
unsigned char flags, mask; | |
end_pak_buffer = pak_buffer + pak_len; | |
inc_len = ((unsigned int *)end_pak_buffer)[-1]; | |
if (!inc_len) { | |
enc_len = 0; | |
dec_len = pak_len - 4; | |
pak_len = 0; | |
raw_len = dec_len; | |
} else { | |
if (pak_len < 8) EXIT("File has a bad header\n"); | |
hdr_len = ((unsigned int *)end_pak_buffer)[-2]; | |
if (pak_len <= hdr_len) EXIT("Bad length\n"); | |
enc_len = ((unsigned int *)end_pak_buffer)[-3] & RAW_MAXIM; | |
dec_len = pak_len - enc_len; | |
pak_len = enc_len - hdr_len; | |
raw_len = dec_len + enc_len + inc_len; | |
if (raw_len > RAW_MAXIM) EXIT("Bad decoded length\n"); | |
} | |
raw_buffer = (unsigned char *) Memory(raw_len, sizeof(char)); | |
pak = pak_buffer; | |
raw = raw_buffer; | |
pak_end = pak_buffer + dec_len + pak_len; | |
raw_end = raw_buffer + raw_len; | |
for (len = 0; len < dec_len; len++) *raw++ = *pak++; | |
BLZ_Invert(pak_buffer + dec_len, pak_len); | |
mask = 0; | |
while (raw < raw_end) { | |
if (!(mask >>= BLZ_SHIFT)) { | |
if (pak == pak_end) break; | |
flags = *pak++; | |
mask = BLZ_MASK; | |
} | |
if (!(flags & mask)) { | |
if (pak == pak_end) break; | |
*raw++ = *pak++; | |
} else { | |
if (pak + 1 >= pak_end) break; | |
pos = *pak++ << 8; | |
pos |= *pak++; | |
len = (pos >> 12) + BLZ_THRESHOLD + 1; | |
if (raw + len > raw_end) { | |
printf(", WARNING: wrong decoded length!"); | |
len = raw_end - raw; | |
} | |
pos = (pos & 0xFFF) + 3; | |
while (len--) *raw++ = *(raw - pos); | |
} | |
} | |
BLZ_Invert(raw_buffer + dec_len, raw_len - dec_len); | |
raw_len = raw - raw_buffer; | |
if (raw != raw_end) printf(", WARNING: unexpected end of encoded file!"); | |
free(pak_buffer); | |
*unpak_len = raw_len; | |
return raw_buffer; | |
} | |
/*----------------------------------------------------------------------------*/ | |
u8* BLZ_Encode(char *filename, u32* pak_len, int mode) { | |
u8 *raw_buffer, *pak_buffer, *new_buffer; | |
u32 raw_len, new_len; | |
raw_buffer = Load(filename, &raw_len, RAW_MINIM, RAW_MAXIM); | |
pak_buffer = NULL; | |
*pak_len = BLZ_MAXIM + 1; | |
new_buffer = BLZ_Code(raw_buffer, raw_len, &new_len, mode); | |
if (new_len < *pak_len) { | |
if (pak_buffer != NULL) free(pak_buffer); | |
pak_buffer = new_buffer; | |
*pak_len = new_len; | |
} | |
return pak_buffer; | |
} | |
/*----------------------------------------------------------------------------*/ | |
u8 *BLZ_Code(u8 *raw_buffer, int raw_len, u32 *new_len, int best) { | |
u8 *pak_buffer, *pak, *raw, *raw_end, *flg = NULL, *tmp; | |
u32 pak_len, inc_len, hdr_len, enc_len, len, pos, max; | |
u32 len_best, pos_best = 0, len_next, pos_next, len_post, pos_post; | |
u32 pak_tmp, raw_tmp; | |
u8 mask; | |
#define SEARCH(l,p) { \ | |
l = BLZ_THRESHOLD; \ | |
\ | |
max = raw - raw_buffer >= BLZ_N ? BLZ_N : raw - raw_buffer; \ | |
for (pos = 3; pos <= max; pos++) { \ | |
for (len = 0; len < BLZ_F; len++) { \ | |
if (raw + len == raw_end) break; \ | |
if (len >= pos) break; \ | |
if (*(raw + len) != *(raw + len - pos)) break; \ | |
} \ | |
\ | |
if (len > l) { \ | |
p = pos; \ | |
if ((l = len) == BLZ_F) break; \ | |
} \ | |
} \ | |
} | |
pak_tmp = 0; | |
raw_tmp = raw_len; | |
pak_len = raw_len + ((raw_len + 7) / 8) + 15; | |
pak_buffer = (u8 *) Memory(pak_len, sizeof(char)); | |
BLZ_Invert(raw_buffer, raw_len); | |
pak = pak_buffer; | |
raw = raw_buffer; | |
raw_end = raw_buffer + raw_len; | |
mask = 0; | |
while (raw < raw_end) { | |
if (!(mask >>= BLZ_SHIFT)) { | |
*(flg = pak++) = 0; | |
mask = BLZ_MASK; | |
} | |
SEARCH(len_best, pos_best); | |
// LZ-CUE optimization start | |
if (best) { | |
if (len_best > BLZ_THRESHOLD) { | |
if (raw + len_best < raw_end) { | |
raw += len_best; | |
SEARCH(len_next, pos_next); | |
raw -= len_best - 1; | |
SEARCH(len_post, pos_post); | |
raw--; | |
if (len_next <= BLZ_THRESHOLD) len_next = 1; | |
if (len_post <= BLZ_THRESHOLD) len_post = 1; | |
if (len_best + len_next <= 1 + len_post) len_best = 1; | |
} | |
} | |
} | |
// LZ-CUE optimization end | |
*flg <<= 1; | |
if (len_best > BLZ_THRESHOLD) { | |
raw += len_best; | |
*flg |= 1; | |
*pak++ = ((len_best - (BLZ_THRESHOLD+1)) << 4) | ((pos_best - 3) >> 8); | |
*pak++ = (pos_best - 3) & 0xFF; | |
} else { | |
*pak++ = *raw++; | |
} | |
if (pak - pak_buffer + raw_len - (raw - raw_buffer) < pak_tmp + raw_tmp) { | |
pak_tmp = pak - pak_buffer; | |
raw_tmp = raw_len - (raw - raw_buffer); | |
} | |
} | |
while (mask && (mask != 1)) { | |
mask >>= BLZ_SHIFT; | |
*flg <<= 1; | |
} | |
pak_len = pak - pak_buffer; | |
BLZ_Invert(raw_buffer, raw_len); | |
BLZ_Invert(pak_buffer, pak_len); | |
if (!pak_tmp || (raw_len + 4 < ((pak_tmp + raw_tmp + 3) & -4) + 8)) { | |
pak = pak_buffer; | |
raw = raw_buffer; | |
raw_end = raw_buffer + raw_len; | |
while (raw < raw_end) *pak++ = *raw++; | |
while ((pak - pak_buffer) & 3) *pak++ = 0; | |
*(u32 *)pak = 0; pak += 4; | |
} else { | |
tmp = (u8 *) Memory(raw_tmp + pak_tmp + 15, sizeof(char)); | |
for (len = 0; len < raw_tmp; len++) | |
tmp[len] = raw_buffer[len]; | |
for (len = 0; len < pak_tmp; len++) | |
tmp[raw_tmp + len] = pak_buffer[len + pak_len - pak_tmp]; | |
pak = pak_buffer; | |
pak_buffer = tmp; | |
free(pak); | |
pak = pak_buffer + raw_tmp + pak_tmp; | |
enc_len = pak_tmp; | |
hdr_len = 12; | |
inc_len = raw_len - enc_len - raw_tmp; | |
while ((pak - pak_buffer) & 3) { | |
*pak++ = 0xFF; | |
hdr_len++; | |
} | |
*(u32 *)pak = enc_len + hdr_len; pak += 4; | |
*(u32 *)pak = hdr_len; pak += 4; | |
*(u32 *)pak = inc_len - hdr_len; pak += 4; | |
} | |
*new_len = pak - pak_buffer; | |
return(pak_buffer); | |
} | |
/*----------------------------------------------------------------------------*/ | |
void BLZ_Invert(u8 *buffer, int length) { | |
u8 *bottom, ch; | |
bottom = buffer + length - 1; | |
while (buffer < bottom) { | |
ch = *buffer; | |
*buffer++ = *bottom; | |
*bottom-- = ch; | |
} | |
} | |
/*----------------------------------------------------------------------------*/ | |
/*-- EOF Copyright (C) 2011 CUE --*/ | |
/*----------------------------------------------------------------------------*/ |
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