| /* vi: set sw=4 ts=4: |
| * |
| * date.c - set/get the date |
| * |
| * Copyright 2012 Andre Renaud <andre@bluewatersys.com> |
| * |
| * See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/date.html |
| |
| USE_DATE(NEWTOY(date, "u", TOYFLAG_BIN)) |
| |
| config DATE |
| bool "date" |
| default y |
| help |
| usage: date [-u] [+format] | mmddhhmm[[cc]yy] |
| |
| Set/get the current date/time |
| */ |
| |
| #include "toys.h" |
| |
| /* Convert a string of decimal numbers to their integer equivalent */ |
| static int fromdec(const char *buf, int len) |
| { |
| int result = 0; |
| while (len--) |
| result=result * 10 + (*buf++ - '0'); |
| return result; |
| } |
| |
| void date_main(void) |
| { |
| const char *format_string = "%a %b %e %H:%M:%S %Z %Y"; |
| |
| /* Check if we should be displaying the date */ |
| if (!toys.optargs[0] || toys.optargs[0][0] == '+') { |
| time_t now = time(NULL); |
| struct tm *tm; |
| if (toys.optargs[0]) |
| format_string = &toys.optargs[0][1]; |
| if (toys.optflags) |
| tm = gmtime(&now); |
| else |
| tm = localtime(&now); |
| if (!tm) |
| perror_msg("Unable to retrieve current time"); |
| if (!strftime(toybuf, sizeof(toybuf), format_string, tm)) |
| perror_msg("invalid format string `%s'", format_string); |
| puts(toybuf); |
| } else { |
| int len = strlen(toys.optargs[0]); |
| struct tm tm; |
| struct timeval tv; |
| |
| if (len < 8 || len > 12 || len & 1) |
| error_msg("invalid date `%s'", toys.optargs[0]); |
| memset(&tm, 0, sizeof(tm)); |
| /* Date format: mmddhhmm[[cc]yy] */ |
| tm.tm_mon = fromdec(toys.optargs[0], 2) - 1; |
| tm.tm_mday = fromdec(&toys.optargs[0][2], 2); |
| tm.tm_hour = fromdec(&toys.optargs[0][4], 2); |
| tm.tm_min = fromdec(&toys.optargs[0][6], 2); |
| if (len == 12) |
| tm.tm_year = fromdec(&toys.optargs[0][8], 4) - 1900; |
| else if (len == 10) { |
| tm.tm_year = fromdec(&toys.optargs[0][8], 2); |
| /* 69-99 = 1969-1999, 0 - 68 = 2000-2068 */ |
| if (tm.tm_year < 69) |
| tm.tm_year += 100; |
| } else { |
| /* Year not specified, so retrieve current year */ |
| time_t now = time(NULL); |
| struct tm *now_tm = localtime(&now); |
| if (!now_tm) |
| perror_msg("Unable to retrieve current time"); |
| tm.tm_year = now_tm->tm_year; |
| } |
| if (!toys.optflags) |
| tv.tv_sec = mktime(&tm); |
| else { |
| /* Get the UTC version of a struct tm */ |
| char *tz = NULL; |
| tz = getenv("TZ"); |
| setenv("TZ", "", 1); |
| tzset(); |
| tv.tv_sec = mktime(&tm); |
| if (tz) |
| setenv("TZ", tz, 1); |
| else |
| unsetenv("TZ"); |
| tzset(); |
| } |
| |
| if (tv.tv_sec == (time_t)-1) |
| error_msg("invalid date `%s'", toys.optargs[0]); |
| tv.tv_usec = 0; |
| if (!strftime(toybuf, sizeof(toybuf), format_string, &tm)) |
| perror_msg("invalid format string `%s'", format_string); |
| puts(toybuf); |
| if (settimeofday(&tv, NULL) < 0) |
| perror_msg("cannot set date"); |
| } |
| } |