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 USE_TOUCH(NEWTOY(touch, "<1acd:mr:t:h[!dtr]", TOYFLAG_BIN))
8
9 config TOUCH
10 bool "touch"
11 default y
12 help
13 usage: touch [-amch] [-d DATE] [-t TIME] [-r FILE] FILE...
14
15 Update the access and modification times of each FILE to the current time.
16
17 -a change access time
18 -m change modification time
19 -c don't create file
20 -h change symlink
21 -d set time to DATE (in YYYY-MM-DDThh:mm:SS[.frac][tz] format)
22 -t set time to TIME (in [[CC]YY]MMDDhhmm[.ss][frac] format)
23 -r set time same as reference FILE
24 */
25
26 #define FOR_touch
27 #include "toys.h"
28
GLOBALS(char * time;char * file;char * date;)29 GLOBALS(
30 char *time;
31 char *file;
32 char *date;
33 )
34
35 void touch_main(void)
36 {
37 struct timespec ts[2];
38 char **ss;
39 int fd, i;
40
41 // use current time if no -t or -d
42 ts[0].tv_nsec = UTIME_NOW;
43 if (toys.optflags & (FLAG_t|FLAG_d)) {
44 char *s, *date, **format;
45 struct tm tm;
46 int len = 0;
47
48 // Initialize default values for time fields
49 ts->tv_sec = time(0);
50 ts->tv_nsec = 0;
51
52 // List of search types
53 if (toys.optflags & FLAG_d) {
54 format = (char *[]){"%Y-%m-%dT%T", "%Y-%m-%d %T", 0};
55 date = TT.date;
56 } else {
57 format = (char *[]){"%m%d%H%M", "%y%m%d%H%M", "%C%y%m%d%H%M", 0};
58 date = TT.time;
59 }
60
61 // Trailing Z means UTC timezone, don't expect libc to know this.
62 i = strlen(s = date);
63 if (i && toupper(date[i-1])=='Z') {
64 date[i-1] = 0;
65 setenv("TZ", "UTC0", 1);
66 }
67
68 while (*format) {
69 if (toys.optflags&FLAG_t) {
70 s = strchr(date, '.');
71 if ((s ? s-date : strlen(date)) != strlen(*format)) {
72 format++;
73 continue;
74 }
75 }
76 localtime_r(&(ts->tv_sec), &tm);
77 // Adjusting for daylight savings time gives the wrong answer.
78 tm.tm_isdst = 0;
79 tm.tm_sec = 0;
80 s = strptime(date, *format++, &tm);
81
82 // parse nanoseconds
83 if (s && *s=='.' && isdigit(s[1])) {
84 s++;
85 if (toys.optflags&FLAG_t)
86 if (1 == sscanf(s, "%2u%n", &(tm.tm_sec), &len)) s += len;
87 if (1 == sscanf(s, "%lu%n", &ts->tv_nsec, &len)) {
88 s += len;
89 if (ts->tv_nsec > 999999999) s = 0;
90 else while (len++ < 9) ts->tv_nsec *= 10;
91 }
92 }
93 if (s && !*s) break;
94 }
95
96 errno = 0;
97 ts->tv_sec = mktime(&tm);
98 if (!s || *s || ts->tv_sec == -1) perror_exit("bad '%s'", date);
99 }
100 ts[1]=ts[0];
101
102 // Set time from -r?
103
104 if (TT.file) {
105 struct stat st;
106
107 xstat(TT.file, &st);
108 ts[0] = st.st_atim;
109 ts[1] = st.st_mtim;
110 }
111
112 // Which time(s) should we actually change?
113 i = toys.optflags & (FLAG_a|FLAG_m);
114 if (i && i!=(FLAG_a|FLAG_m)) ts[i==FLAG_m].tv_nsec = UTIME_OMIT;
115
116 // Loop through files on command line
117 for (ss = toys.optargs; *ss;) {
118 char *s = *ss++;
119
120 if (!strcmp(s, "-")) {
121 if (!futimens(1, ts)) continue;
122 } else {
123 // cheat: FLAG_h is rightmost flag, so its value is 1
124 if (!utimensat(AT_FDCWD, s, ts,
125 (toys.optflags & FLAG_h)*AT_SYMLINK_NOFOLLOW)) continue;
126 if (toys.optflags & FLAG_c) continue;
127 if (access(s, F_OK) && (-1!=(fd = open(s, O_CREAT, 0666)))) {
128 close(fd);
129 if (toys.optflags) ss--;
130 continue;
131 }
132 }
133 perror_msg("'%s'", s);
134 }
135 }
136