minecraft-pi-docker/libreborn/include/libreborn/exec.h
2021-06-17 17:32:24 -04:00

72 lines
2.0 KiB
C

#pragma once
#include <unistd.h>
#include <stdint.h>
#include <errno.h>
#include <sys/stat.h>
#include <limits.h>
#include <string.h>
#include "log.h"
#include "string.h"
#include "util.h"
// Safe execvpe()
__attribute__((noreturn)) static inline void safe_execvpe(const char *pathname, char *argv[], char *const envp[]) {
argv[0] = (char *) pathname;
int ret = execvpe(pathname, argv, envp);
if (ret == -1) {
ERR("Unable To Execute Program: %s: %s", pathname, strerror(errno));
} else {
ERR("%s", "Unknown execvpe() Error");
}
}
// Get Binary Directory (Remember To Free)
#define EXE_PATH "/proc/self/exe"
static inline char *get_binary_directory() {
// Get Path To Current Executable
// Get Symlink Path Size
struct stat sb;
if (lstat(EXE_PATH, &sb) == -1) {
ERR("Unable To Get " EXE_PATH " Symlink Size: %s", strerror(errno));
}
ssize_t path_size = sb.st_size + 1;
if (sb.st_size == 0) {
path_size = PATH_MAX;
}
char *exe = (char *) malloc(path_size);
ALLOC_CHECK(exe);
// Read Link
ssize_t r = readlink(EXE_PATH, exe, path_size);
if (r < 0) {
ERR("Unable To Read " EXE_PATH " Symlink: %s", strerror(errno));
}
if (r > path_size) {
ERR("%s", "Size Of Symlink " EXE_PATH " Changed");
}
exe[path_size] = '\0';
// Chop Off Last Component
for (int i = path_size - 1; i >= 0; i--) {
if (exe[i] == '/') {
exe[i] = '\0';
break;
}
}
// Return
return exe;
}
// Safe execvpe() Relative To Binary
__attribute__((noreturn)) static inline void safe_execvpe_relative_to_binary(const char *pathname, char *argv[], char *const envp[]) {
// Get Binary Directory
char *binary_directory = get_binary_directory();
// Create Full Path
char *full_path = NULL;
safe_asprintf(&full_path, "%s/%s", binary_directory, pathname);
// Free Binary Directory
free(binary_directory);
// Run
safe_execvpe(full_path, argv, envp);
}