toaruos/apps/which.c
2018-08-15 10:07:33 +09:00

65 lines
1.4 KiB
C

/* vim: tabstop=4 shiftwidth=4 noexpandtab
* This file is part of ToaruOS and is released under the terms
* of the NCSA / University of Illinois License - see LICENSE.md
* Copyright (C) 2013-2014 K. Lange
*
* which - Figure out which binary will be used
*
* Searches through $PATH to find a matching binary, just like
* how execp* family does it. (Except does our execp actually
* bother checking permissions? Look into this...)
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#define DEFAULT_PATH "/bin:/usr/bin"
int main(int argc, char * argv[]) {
if (argc < 2) {
return 1;
}
if (strstr(argv[1], "/")) {
struct stat t;
if (!stat(argv[1], &t)) {
if ((t.st_mode & 0111)) {
printf("%s\n", argv[1]);
return 0;
}
}
} else {
char * file = argv[1];
char * path = getenv("PATH");
if (!path) {
path = DEFAULT_PATH;
}
char * xpath = strdup(path);
char * p, * last;
for ((p = strtok_r(xpath, ":", &last)); p; p = strtok_r(NULL, ":", &last)) {
int r;
struct stat stat_buf;
char * exe = malloc(strlen(p) + strlen(file) + 2);
strcpy(exe, p);
strcat(exe, "/");
strcat(exe, file);
r = stat(exe, &stat_buf);
if (r != 0) {
continue;
}
if (!(stat_buf.st_mode & 0111)) {
continue; /* XXX not technically correct; need to test perms */
}
printf("%s\n", exe);
return 0;
}
free(xpath);
return 1;
}
return 1;
}