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jsmolina/dat.c

Created August 22, 2024 16:50
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Simplest ever static files compacter for games onto one datafile. Use dat.c as a commandline utility to generate data.dat file, use dat_manager to uncompress on runtime.
Raw
dat.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dirent.h>
#include <sys/stat.h>
#include <unistd.h>
// Code based on mills32 Little-Game-Engine-for-VGA-EGA
struct dirent *direntry;
struct stat s;
unsigned char nfiles = 0;
DIR *folder;
int check_ext(unsigned char *name){
int type = 0;
int len = strlen((const char*)name);
unsigned long *ext = (unsigned long*) &name[len-4];
switch (ext[0]){
//file extensions
case 0x504D422E:
case 0x706D622E: printf("A BMP\n"); type = 1; break;
case 0x584D542E:
case 0x786D742E: printf("A TMX\n"); type = 2; break;
case 0x4D47562E:
case 0x6D67762E: printf("A VGM\n"); type = 3; break;
}
return type;
}
int main(int argc, char **argv) {
unsigned short filesize = 0x0000;
unsigned long dat_offset = 32 + 2048;
unsigned long file_pos = 0;
unsigned char i, arg;
unsigned char ssize = 0;
unsigned char *extract_file;
unsigned char number = argc-1;
FILE *dat;
FILE *file;
unsigned char *buffer = (unsigned char*) calloc(1,65535);
unsigned char is_folder = 0;
printf("- Static files compacter (based on Mills32 code) starting...");
if (!argv[1]) {printf("\nusage\n- Create dat: makedat file1 file2 ...\n- List dat: makedat -l FILE.DAT\n"); return 0;}
if (argc > 64) {printf("\nOnly 64 files are supported\n"); return 0;}
extract_file = (unsigned char*)argv[1];
if ((extract_file[0] == '-')&&(extract_file[1] == 'l')) {
printf("\nFiles in dat:\n");
unsigned char *name = (unsigned char*)argv[2];
if (!argv[2]) {printf("\nSpecify a DAT file: -e FILE.DAT\n"); return 1;}
dat = fopen((const char*)name,"rb");
if (!dat) {printf("Can't open the file %s!\n", name); return 1;}
fseek(dat, 22, SEEK_SET);
fread(&number,1,1,dat);
for (i=1; i<number+1; i++) {
int type = 0;
fseek(dat, 32*i, SEEK_SET);
memset(buffer,0,16);
//Read file name
fread(buffer,1,16,dat);
printf("- %s\n",buffer);
}
fclose(dat);
return 0;
}
printf("\n");
//Is it a folder?
stat(argv[1],&s);
if (s.st_mode & S_IFDIR) is_folder = 1;
//CREATE FILE
dat = fopen("DATA.DAT","wb");
fprintf(dat,"LDAT LT-ENGINE FILES: ");
fseek(dat, 22, SEEK_SET); fwrite(&number,1,1,dat);
if (!is_folder){
for (arg=1; arg<argc; arg++) {
int i = 0;
int namepos = 0;
int type = 0;
int index = 0;
char line[128];
unsigned char start_map_data = 0;
unsigned char *name = (unsigned char*)argv[arg];
//if dropped file (windows) remove path
for (i = 0; i < strlen((const char*)name);i++){if (name[i] == 0x5C) namepos = i+1;}
memmove(&name[0],&name[namepos],16);
//Print file name
fseek(dat, arg*32, SEEK_SET);
fprintf(dat,"%s",name);
if ((strlen((const char*)name))>12){printf("\nCan't use names bigger than 8 characters %s\n",name); return 0;}
//Check file type
type = check_ext(name);
//if (!type){printf("file format not recognized %s\n",name);return 0;}
//Read file to insert
file = fopen((const char*)name,"rb");
if (!file) {printf("\nCan't find %s\n",name); return 0;}
fseek(file, 0, SEEK_END);
filesize = ftell(file);
rewind(file);
fread(buffer,filesize,1,file);
//Write file offset in data, and file size
file_pos = dat_offset;
fseek(dat, (arg*32)+16, SEEK_SET);
fwrite(&file_pos,4,1,dat);
fwrite(&filesize,2,1,dat);
//Write actual file
fseek(dat,file_pos, SEEK_SET);
fwrite(buffer,filesize,1,dat);
dat_offset += filesize;
fclose(file);
}
} else {
//READ FOLDER
chdir(argv[1]);
folder = opendir(".");
nfiles = 1;
while((direntry = readdir(folder)) != NULL){
stat(direntry->d_name,&s);
if (!(s.st_mode & S_IFDIR)) {
int i = 0;
int namepos = 0;
int type = 0;
int index = 0;
char line[128];
unsigned char start_map_data = 0;
unsigned char *name = (unsigned char*)direntry->d_name;
//if dropped file (windows) remove path
for (i = 0; i < strlen((const char*)name);i++){
if (name[i] == 0x5C) namepos = i+1;
}
memmove(&name[0],&name[namepos],16);
//Print file name
fseek(dat, nfiles*32, SEEK_SET);
fprintf(dat,"%s",name);
if ((strlen((const char*)name))>12){printf("\nCan't use names bigger than 8 characters %s\n",name); return 0;}
//Check file type
type = check_ext(name);
//if (!type){printf("file format not recognized %s\n",name);return 0;}
//Read file to insert
file = fopen((const char*)name,"rb");
if (!file) {printf("\nCan't find %s\n",name); return 0;}
switch (type){
case 0:
case 1:
case 3://BMP VGM or unknown
fseek(file, 0, SEEK_END);
filesize = ftell(file);
rewind(file);
fread(buffer,filesize,1,file);
break;
case 2://store tmx maps more efficiently
while(!start_map_data){ //read lines
memset(line, 0, 64);
fgets(line, 64, file);
if((line[2] == '<')&&(line[3] == 'd')) start_map_data = 1;//<data encoding="csv">
}
start_map_data = 0;
filesize = ftell(file);
//Read header
fseek(file, 0, SEEK_SET);
fread(buffer,filesize,1,file);
//read map in bytes
for (index = 0; index < 256*19; index++){
unsigned char tile = 0;
fscanf(file, "%c,",&tile);if (!tile) tile++;
buffer[filesize++] = tile;
}
//advance to bkg map
while(!start_map_data){ //read lines
memset(line, 0, 64);
fgets(line, 64, file);
if((line[2] == '<')&&(line[3] == 'd')) start_map_data = 1;//<data encoding="csv">
}
//paste lines
sprintf((char*)&buffer[filesize],"\n</data>\n </layer>\n <layer id=\"2\" name=\"col\" width=\"256\" height=\"19\">\n <data encoding=\"csv\">\n");
filesize+= 94;
//read bkg map in bytes
for (index = 0; index < 256*19; index++){
unsigned char tile = 0;
fscanf(file, "%c,",&tile);if (!tile) tile++;
buffer[filesize++] = tile;
}
//paste end
sprintf((char*)&buffer[filesize],"\n</data>\n </layer>\n</map>\n");
filesize+= 26;
break;
}
file_pos = dat_offset;
//Write file offset in data, and file size
fseek(dat, (nfiles*32)+16, SEEK_SET);
fwrite(&file_pos,sizeof(dat_offset),1,dat);
fwrite(&filesize,sizeof(filesize),1,dat);
//Write actual file
fseek(dat,file_pos, SEEK_SET);
fwrite(buffer,filesize,1,dat);
dat_offset += filesize;
nfiles++;
}
}
}
fclose(dat);
printf("- DATA.DAT CREATED\n");
free(buffer);
buffer = NULL;
return 0;
}
Raw
dat_manager.c
#include <dirent.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
struct dirent *direntry;
struct stat s;
unsigned char nfiles = 0;
DIR *folder;
struct stat st = {0};
int check_ext(unsigned char *name) {
int type = 0;
int len = strlen((const char *)name);
unsigned long *ext = (unsigned long *)&name[len - 4];
switch (ext[0]) {
// file extensions
case 0x504D422E:
case 0x706D622E:
printf("A BMP\n");
type = 1;
break;
case 0x584D542E:
case 0x786D742E:
printf("A TMX\n");
type = 2;
break;
case 0x4D47562E:
case 0x6D67762E:
printf("A VGM\n");
type = 3;
break;
}
return type;
}
unsigned int extract_data() {
unsigned short filesize = 0x0000;
unsigned long dat_offset = 32 + 2048;
unsigned long file_pos = 0;
unsigned char i, arg;
unsigned char ssize = 0;
unsigned char extract = 0;
unsigned char *extract_file;
unsigned int number = 0;
FILE *dat;
FILE *file;
unsigned char *filename = (unsigned char *)calloc(1, 65535);
// EXTRACT FILES
dat = fopen("DATA.DAT", "rb");
if (stat("data", &st) == -1) {
mkdir("data", 0700);
}
chdir("data");
fseek(dat, 22, SEEK_SET);
fread(&number, 1, 1, dat);
for (i = 1; i < number + 1; i++) {
int type = 0;
fseek(dat, 32 * i, SEEK_SET);
memset(filename, 0, 16);
// Read file name
fread(filename, 1, 16, dat);
printf("Extracting: %s\n", filename);
// Read data offset
fread(&dat_offset, 4, 1, dat);
// Check file type
type = check_ext(filename);
// read file size
fread(&filesize, 2, 1, dat);
// Go to data offset
fseek(dat, dat_offset, SEEK_SET);
// Open file
file = fopen((const char *)filename, "wb");
// write file
fread(filename, filesize, 1, dat);
fwrite(filename, filesize, 1, file);
fclose(file);
}
fclose(dat);
free(filename);
filename = NULL;
return 0;
}
void cleanup_data() {
chdir("..");
}
Raw
dat_manager.h
#ifndef DAT_MANAGER
#define DAT_MANAGER
unsigned int extract_data();
void cleanup_data();
#endif
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