toaruos/apps/chown.c

115 lines
2.4 KiB
C

/**
* @brief chown - bad implementation thereof
*
* @copyright
* This file is part of ToaruOS and is released under the terms
* of the NCSA / University of Illinois License - see LICENSE.md
* Copyright (C) 2018 K. Lange
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#include <pwd.h>
static int usage(char * argv[]) {
fprintf(stderr, "usage: %s [OWNER][:[GROUP]] FILE...\n", argv[0]);
return 1;
}
static int invalid(char * argv[], char c) {
fprintf(stderr, "%s: %c: unrecognized option\n", argv[0], c);
return 1;
}
static int parse_user_group(char * argv[], char * arg, uid_t * user, gid_t * group) {
/* Does this look like a number? */
if (*arg >= '0' && *arg <= '9') {
/* Try to extract */
char * endptr;
unsigned long int number = strtoul(arg, &endptr, 10);
if (*endptr != ':' && *endptr != '\0') {
fprintf(stderr, "%s: %s: Invalid user/group specification\n", argv[0], arg);
}
*user = number;
arg = endptr;
} else if (*arg == ':') {
*user = -1;
arg++;
} else {
char * colon = strstr(arg, ":");
if (colon) {
*colon = '\0';
}
/* Check name */
struct passwd * userEnt = getpwnam(arg);
if (!userEnt) {
fprintf(stderr, "%s: %s: Invalid user\n", argv[0], arg);
return 1;
}
*user = userEnt->pw_uid;
if (colon) {
arg = colon + 1;
} else {
arg = NULL;
}
}
if (arg && *arg) {
if (*arg >= '0' && *arg <= '9') {
char * endptr;
unsigned long int number = strtoul(arg, &endptr, 10);
if (*endptr != '\0') {
fprintf(stderr, "%s: %s: Invalid group specification\n", argv[0], arg);
}
*group = number;
arg = endptr;
} else {
struct passwd * userEnt = getpwnam(arg);
if (!userEnt) {
fprintf(stderr, "%s: %s: Invalid group\n", argv[0], arg);
return 1;
}
*group = userEnt->pw_uid;
}
}
return 0;
}
int main(int argc, char * argv[]) {
int i = 1;
for (; i < argc; i++) {
if (argv[i][0] != '-') break;
switch (argv[i][0]) {
case 'h':
return usage(argv);
default:
return invalid(argv,argv[i][0]);
}
}
if (i + 1 >= argc) return usage(argv);
uid_t user = -1;
uid_t group = -1;
if (parse_user_group(argv, argv[i++], &user, &group)) return 1;
if (user == -1 && group == -1) return 0;
int retval = 0;
for (; i < argc; i++) {
if (chown(argv[i], user, group)) {
fprintf(stderr, "%s: %s: %s\n", argv[0], argv[i], strerror(errno));
retval = 1;
}
}
return retval;
}