minecraft-pi-reborn/mods/src/override/override.c
2022-03-09 18:47:31 -05:00

88 lines
2.1 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include <fcntl.h>
#include <libreborn/libreborn.h>
#include "../home/home.h"
// Check If String Starts With Prefix
static int starts_with(const char *s, const char *t) {
return strncmp(s, t, strlen(t)) == 0;
}
// Get Override Path For File (If It Exists)
char *override_get_path(const char *filename) {
// Get MCPI Home Path
char *home_path = home_get();
// Get Asset Override Path
char *overrides = NULL;
safe_asprintf(&overrides, "%s/overrides", home_path);
// Get Data Path
char *data = NULL;
char *binary_directory = get_mcpi_directory();
safe_asprintf(&data, "%s/data", binary_directory);
int data_length = strlen(data);
// Get Full Path
char *full_path;
if (strlen(filename) > 0 && filename[0] == '/') {
// Absolute Path
full_path = strdup(filename);
} else {
// Relative Path
full_path = realpath(filename, NULL);
}
// Check For Override
char *new_path = NULL;
if (full_path != NULL) {
if (starts_with(full_path, data)) {
safe_asprintf(&new_path, "%s%s", overrides, &full_path[data_length]);
if (access(new_path, F_OK) == -1) {
free(new_path);
new_path = NULL;
}
}
free(full_path);
}
// Free Variables
free(overrides);
free(data);
// Return
return new_path;
}
HOOK(fopen, FILE *, (const char *filename, const char *mode)) {
char *new_path = override_get_path(filename);
// Open File
ensure_fopen();
FILE *file = (*real_fopen)(new_path != NULL ? new_path : filename, mode);
// Free Data
if (new_path != NULL) {
free(new_path);
}
// Return File
return file;
}
HOOK(fopen64, FILE *, (const char *filename, const char *mode)) {
char *new_path = override_get_path(filename);
// Open File
ensure_fopen64();
FILE *file = (*real_fopen64)(new_path != NULL ? new_path : filename, mode);
// Free Data
if (new_path != NULL) {
free(new_path);
}
// Return File
return file;
}