minecraft-pi-docker/core/src/launcher.c
2020-09-25 14:52:28 -04:00

93 lines
2.7 KiB
C

#define _FILE_OFFSET_BITS 64
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <dirent.h>
#include <errno.h>
static int starts_with(const char *s, const char *t) {
return strncmp(s, t, strlen(t)) == 0;
}
static int ends_with(const char *s, const char *t) {
size_t slen = strlen(s);
size_t tlen = strlen(t);
if (tlen > slen) return 1;
return strcmp(s + slen - tlen, t) == 0;
}
#define MODS_FOLDER "./mods/"
static void set_and_print_env(char *name, char *value) {
int length = strlen(value);
if (value[length - 1] == ':') {
value[length - 1] = '\0';
}
fprintf(stderr, "Set %s = %s\n", name, value);
setenv(name, value, 1);
}
static char *get_env_safe(const char *name) {
char *ret = getenv(name);
return ret != NULL ? ret : "";
}
int main(__attribute__((unused)) int argc, char *argv[]) {
fprintf(stderr, "Configuring Game...\n");
char *ld_path = NULL;
char *cwd = getcwd(NULL, 0);
asprintf(&ld_path, "%s:/usr/arm-linux-gnueabihf/lib:%s", cwd, get_env_safe("LD_LIBRARY_PATH"));
free(cwd);
set_and_print_env("LD_LIBRARY_PATH", ld_path);
free(ld_path);
char *ld_preload = NULL;
asprintf(&ld_preload, "%s", get_env_safe("LD_PRELOAD"));
int folder_name_length = strlen(MODS_FOLDER);
DIR *dp = opendir(MODS_FOLDER);
if (dp != NULL) {
struct dirent *entry = NULL;
errno = 0;
while (1) {
entry = readdir(dp);
if (entry != NULL) {
if (starts_with(entry->d_name, "lib") && ends_with(entry->d_name, ".so")) {
int name_length = strlen(entry->d_name);
int total_length = folder_name_length + name_length;
char name[total_length + 1];
for (int i = 0; i < folder_name_length; i++) {
name[i] = MODS_FOLDER[i];
}
for (int i = 0; i < name_length; i++) {
name[folder_name_length + i] = entry->d_name[i];
}
name[total_length] = '\0';
asprintf(&ld_preload, "%s:%s", name, ld_preload);
}
} else if (errno != 0) {
fprintf(stderr, "Error Reading Directory: %s\n", strerror(errno));
exit(1);
} else {
break;
}
}
} else {
fprintf(stderr, "Error Opening Directory: %s\n", strerror(errno));
exit(1);
}
closedir(dp);
set_and_print_env("LD_PRELOAD", ld_preload);
free(ld_preload);
fprintf(stderr, "Starting Game...\n");
return execve("./minecraft-pi", argv, environ);
}