1 /* touch.c : change timestamp of a file
2 *
3 * Copyright 2012 Choubey Ji <warior.linux@gmail.com>
4 *
5 * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/touch.html
6 *
7 * -f is ignored for BSD/macOS compatibility. busybox/coreutils also support
8 * this, but only coreutils documents it in --help output.
9
10 USE_TOUCH(NEWTOY(touch, "<1acd:fmr:t:h[!dtr]", TOYFLAG_BIN))
11
12 config TOUCH
13 bool "touch"
14 default y
15 help
16 usage: touch [-amch] [-d DATE] [-t TIME] [-r FILE] FILE...
17
18 Update the access and modification times of each FILE to the current time.
19
20 -a Change access time
21 -m Change modification time
22 -c Don't create file
23 -h Change symlink
24 -d Set time to DATE (in YYYY-MM-DDThh:mm:SS[.frac][tz] format)
25 -t Set time to TIME (in [[CC]YY]MMDDhhmm[.ss][frac] format)
26 -r Set time same as reference FILE
27 */
28
29 #define FOR_touch
30 #include "toys.h"
31
32 GLOBALS(
33 char *t, *r, *d;
34 )
35
touch_main(void)36 void touch_main(void)
37 {
38 struct timespec ts[2];
39 char **ss;
40 int fd, i;
41
42 // use current time if no -t or -d
43 ts[0].tv_nsec = UTIME_NOW;
44
45 if (FLAG(t) || FLAG(d)) {
46 time_t t = time(0);
47 unsigned nano;
48
49 xparsedate(TT.t ? TT.t : TT.d, &t, &nano, 0);
50 ts->tv_sec = t;
51 ts->tv_nsec = nano;
52 }
53 ts[1]=ts[0];
54
55 if (TT.r) {
56 struct stat st;
57
58 xstat(TT.r, &st);
59 ts[0] = st.st_atim;
60 ts[1] = st.st_mtim;
61 }
62
63 // Which time(s) should we actually change?
64 i = toys.optflags & (FLAG_a|FLAG_m);
65 if (i && i!=(FLAG_a|FLAG_m)) ts[i!=FLAG_m].tv_nsec = UTIME_OMIT;
66
67 // Loop through files on command line
68 for (ss = toys.optargs; *ss;) {
69 char *s = *ss++;
70
71 if (!strcmp(s, "-")) {
72 if (!futimens(1, ts)) continue;
73 } else {
74 // cheat: FLAG_h is rightmost flag, so its value is 1
75 if (!utimensat(AT_FDCWD, s, ts, FLAG(h)*AT_SYMLINK_NOFOLLOW)) continue;
76 if (FLAG(c)) continue;
77 if (access(s, F_OK) && (-1!=(fd = open(s, O_CREAT, 0666)))) {
78 close(fd);
79 if (toys.optflags) ss--;
80 continue;
81 }
82 }
83 perror_msg("'%s'", s);
84 }
85 }
86