1#include <stdio.h>
2#include <string.h>
3#include <sys/types.h>
4#include <fcntl.h>
5#include <sys/stat.h>
6#include <stdlib.h>
7#include <fcntl.h>
8#include <time.h>
9
10static void usage(void)
11{
12        fprintf(stderr, "touch: usage: touch [-alm] [-t YYYYMMDD[.hhmmss]] <file>\n");
13        exit(1);
14}
15
16static time_t parse_time(char *s)
17{
18    struct tm tm;
19    int day = atoi(s);
20    int hour = 0;
21
22    while (*s && *s != '.') {
23        s++;
24    }
25
26    if (*s) {
27        s++;
28        hour = atoi(s);
29    }
30
31    tm.tm_year = day / 10000 - 1900;
32    tm.tm_mon = (day % 10000) / 100 - 1;
33    tm.tm_mday = day % 100;
34    tm.tm_hour = hour / 10000;
35    tm.tm_min = (hour % 10000) / 100;
36    tm.tm_sec = hour % 100;
37    tm.tm_isdst = -1;
38
39    return mktime(&tm);
40}
41
42int touch_main(int argc, char *argv[])
43{
44        int i, fd, aflag = 0, mflag = 0, debug = 0, flags = 0;
45        struct timespec specified_time, times[2];
46        char *file = 0;
47
48        specified_time.tv_nsec = UTIME_NOW;
49
50        for (i = 1; i < argc; i++) {
51            if (argv[i][0] == '-') {
52                /* an option */
53                const char *arg = argv[i]+1;
54                while (arg[0]) {
55                    switch (arg[0]) {
56                    case 'a': aflag = 1; break;
57                    case 'm': mflag = 1; break;
58                    case 't':
59                        if ((i+1) >= argc)
60                            usage();
61                        specified_time.tv_sec = parse_time(argv[++i]);
62                        if (specified_time.tv_sec == -1) {
63                            fprintf(stderr, "touch: invalid timestamp specified\n");
64                            exit(1);
65                        }
66                        specified_time.tv_nsec = 0;
67                        break;
68                    case 'l': flags |= AT_SYMLINK_NOFOLLOW; break;
69                    case 'd': debug = 1; break;
70                    default:
71                        usage();
72                    }
73                    arg++;
74                }
75            } else {
76                /* not an option, and only accept one filename */
77                if (i+1 != argc)
78                    usage();
79                file = argv[i];
80            }
81        }
82
83        if (! file) {
84            fprintf(stderr, "touch: no file specified\n");
85            exit(1);
86        }
87
88        if (access(file, F_OK))
89            if ((fd=creat(file, 0666)) != -1)
90                close(fd);
91
92        if ((mflag == 0) && (aflag == 0))
93            aflag = mflag = 1;
94
95        if (aflag)
96            times[0] = specified_time;
97        else
98            times[0].tv_nsec = UTIME_OMIT;
99
100        if (mflag)
101            times[1] = specified_time;
102        else
103            times[1].tv_nsec = UTIME_OMIT;
104
105        if (debug) {
106            fprintf(stderr, "file = %s\n", file);
107            fprintf(stderr, "times[0].tv_sec = %ld, times[0].tv_nsec = %ld\n", times[0].tv_sec, times[0].tv_nsec);
108            fprintf(stderr, "times[1].tv_sec = %ld, times[1].tv_nsec = %ld\n", times[1].tv_sec, times[1].tv_nsec);
109            fprintf(stderr, "flags = 0x%8.8x\n", flags);
110        }
111
112        return utimensat(AT_FDCWD, file, times, flags);
113}
114
115