date,touch: treat 2-digit years better (fit them into +-50 yrs around today)

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

2 files changed, 16 insertions, 3 deletions

diff --git a/coreutils/touch.c b/coreutils/touch.c
index 352177111..6c2b948e6 100644
--- a/coreutils/touch.c
+++ b/coreutils/touch.c
@@ -120,9 +120,10 @@ int touch_main(int argc UNUSED_PARAM, char **argv)
                 struct tm tm_time;
                 time_t t;
 
-                //time(&t);
-                //localtime_r(&t, &tm_time);
-                memset(&tm_time, 0, sizeof(tm_time));
+                //memset(&tm_time, 0, sizeof(tm_time));
+                /* Better than memset: makes "HH:MM" dates meaningful */
+                time(&t);
+                localtime_r(&t, &tm_time);
                 parse_datestr(date_str, &tm_time);
 
                 /* Correct any day of week and day of year etc. fields */
diff --git a/libbb/time.c b/libbb/time.c
index 2a74d34c2..1eb2d75c2 100644
--- a/libbb/time.c
+++ b/libbb/time.c
@@ -93,6 +93,7 @@ void FAST_FUNC parse_datestr(const char *date_str, struct tm *ptm)
                  *
                  * This coincides with the format of "touch -t TIME"
                  */
+                unsigned cur_year = ptm->tm_year;
                 int len = strchrnul(date_str, '.') - date_str;
 
                 /* MM[.SS] */
@@ -133,6 +134,17 @@ void FAST_FUNC parse_datestr(const char *date_str, struct tm *ptm)
                                         &end) >= 5) {
                         /* Adjust month from 1-12 to 0-11 */
                         ptm->tm_mon -= 1;
+                        if ((int)cur_year >= 50) { /* >= 1950 */
+                                /* Adjust year: */
+                                /* 1. Put it in the current century */
+                                ptm->tm_year += (cur_year / 100) * 100;
+                                /* 2. If too far in the past, +100 years */
+                                if (ptm->tm_year < cur_year - 50)
+                                        ptm->tm_year += 100;
+                                /* 3. If too far in the future, -100 years */
+                                if (ptm->tm_year > cur_year + 50)
+                                        ptm->tm_year -= 100;
+                        }
                 } else
                 /* ccyymmddHHMM[.SS] */
                 if (len == 12 && sscanf(date_str, "%4u%2u%2u%2u%2u%c",