1 /*
2 * Copyright (c) 2006 Darren Tucker
3 *
4 * Permission to use, copy, modify, and distribute this software for any
5 * purpose with or without fee is hereby granted, provided that the above
6 * copyright notice and this permission notice appear in all copies.
7 *
8 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15 */
16
17 #include "includes.h"
18
19 #include <sys/types.h>
20 #include <sys/stat.h>
21
22 #include <fcntl.h>
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <unistd.h>
26
27 #define NUM_OPENS 10
28
29 void
fail(char * msg)30 fail(char *msg)
31 {
32 fprintf(stderr, "closefrom: %s\n", msg);
33 exit(1);
34 }
35
36 int
main(void)37 main(void)
38 {
39 int i, max, fds[NUM_OPENS];
40 char buf[512];
41
42 for (i = 0; i < NUM_OPENS; i++)
43 if ((fds[i] = open("/dev/null", O_RDONLY)) == -1)
44 exit(0); /* can't test */
45 max = i - 1;
46
47 /* should close last fd only */
48 closefrom(fds[max]);
49 if (close(fds[max]) != -1)
50 fail("failed to close highest fd");
51
52 /* make sure we can still use remaining descriptors */
53 for (i = 0; i < max; i++)
54 if (read(fds[i], buf, sizeof(buf)) == -1)
55 fail("closed descriptors it should not have");
56
57 /* should close all fds */
58 closefrom(fds[0]);
59 for (i = 0; i < NUM_OPENS; i++)
60 if (close(fds[i]) != -1)
61 fail("failed to close from lowest fd");
62 return 0;
63 }
64