1 /*
2 * DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
3 * Version 2, December 2004
4 *
5 * Copyright (C) 2017 Olaf Wintermann <olaf.wintermann@gmail.com>
6 *
7 * Everyone is permitted to copy and distribute verbatim or modified
8 * copies of this license document, and changing it is allowed as long
9 * as the name is changed.
10 *
11 * DO WHAT THE FUCK YOU WANT TO PUBLIC LICENSE
12 * TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
13 *
14 * 0. You just DO WHAT THE FUCK YOU WANT TO.
15 */
16
17 #include <sys/types.h>
18 #include <sys/xattr.h>
19 #include <unistd.h>
20 #include <stdio.h>
21 #include <stdlib.h>
22 #include <string.h>
23 #include <errno.h>
24
25 #define BUF_LEN 1024
26
27 // this example is 99.9% identical to the linux xattr example
28
29 int main(int argc, char **argv) {
30 if(argc != 2) {
31 fprintf(stderr, "Usage: %s <file>\n", argv[0]);
32 return -1;
33 }
34
35 char *path = argv[1];
36
37 // get list of extended attribute names
38 char *list = malloc(BUF_LEN);
39 ssize_t len = listxattr(path, list, BUF_LEN, 0);
40
41 if(len == -1) {
42 switch(errno) {
43 case ERANGE: {
44 // buffer too, get size of attribute list
45 ssize_t newlen = listxattr(path, NULL, 0, 0);
46 if(newlen > 0) {
47 // second try
48 list = realloc(list, newlen);
49 len = listxattr(path, list, newlen, 0);
50 if(len != -1) {
51 // this time it worked
52 break;
53 }
54 }
55 }
56 default: perror("listxattr");
57 free(list);
58 return -1;
59 }
60 }
61
62 // print list
63 int begin = 0;
64 for(int i=0;i<len;i++) {
65 if(list[i] == '\0') {
66 printf("%s\n", list + begin);
67 begin = i + 1;
68 }
69 }
70
71 free(list);
72
73 return 0;
74 }
75