blame: show "previous" information in --porcelain/--incremental format

diff --git a/date.c b/date.c
index a74ed86422763e7d7e5dccf73530e52551a6929a..950b88fdcf74f550a582684f1702ffb58c62c7f9 100644 (file)
--- a/date.c
+++ b/date.c
@@ -6,7 +6,10 @@
 
 #include "cache.h"
 
-static time_t my_mktime(struct tm *tm)
+/*
+ * This is like mktime, but without normalization of tm_wday and tm_yday.
+ */
+time_t tm_to_time_t(const struct tm *tm)
 {
        static const int mdays[] = {
            0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334
@@ -67,7 +70,7 @@ static int local_tzoffset(unsigned long time)
 
        t = time;
        localtime_r(&t, &tm);
-       t_local = my_mktime(&tm);
+       t_local = tm_to_time_t(&tm);
 
        if (t_local < t) {
                eastwest = -1;
@@ -322,7 +325,7 @@ static int is_date(int year, int month, int day, struct tm *now_tm, time_t now,
                if (!now_tm)
                        return 1;
 
-               specified = my_mktime(r);
+               specified = tm_to_time_t(r);
 
                /* Be it commit time or author time, it does not make
                 * sense to specify timestamp way into the future.  Make
@@ -399,6 +402,15 @@ static int match_multi_number(unsigned long num, char c, const char *date, char
        return end - date;
 }
 
+/* Have we filled in any part of the time/date yet? */
+static inline int nodate(struct tm *tm)
+{
+       return tm->tm_year < 0 &&
+               tm->tm_mon < 0 &&
+               tm->tm_mday < 0 &&
+               !(tm->tm_hour | tm->tm_min | tm->tm_sec);
+}
+
 /*
  * We've seen a digit. Time? Year? Date?
  */
@@ -415,7 +427,7 @@ static int match_digit(const char *date, struct tm *tm, int *offset, int *tm_gmt
         * more than 8 digits. This is because we don't want to rule out
         * numbers like 20070606 as a YYYYMMDD date.
         */
-       if (num >= 100000000) {
+       if (num >= 100000000 && nodate(tm)) {
                time_t time = num;
                if (gmtime_r(&time, tm)) {
                        *tm_gmt = 1;
@@ -459,6 +471,13 @@ static int match_digit(const char *date, struct tm *tm, int *offset, int *tm_gmt
                return n;
        }
 
+       /*
+        * Ignore lots of numerals. We took care of 4-digit years above.
+        * Days or months must be one or two digits.
+        */
+       if (n > 2)
+               return n;
+
        /*
         * NOTE! We will give precedence to day-of-month over month or
         * year numbers in the 1-12 range. So 05 is always "mday 5",
@@ -485,10 +504,6 @@ static int match_digit(const char *date, struct tm *tm, int *offset, int *tm_gmt
 
        if (num > 0 && num < 32) {
                tm->tm_mday = num;
-       } else if (num > 1900) {
-               tm->tm_year = num - 1900;
-       } else if (num > 70) {
-               tm->tm_year = num;
        } else if (num > 0 && num < 13) {
                tm->tm_mon = num-1;
        }
@@ -572,7 +587,7 @@ int parse_date(const char *date, char *result, int maxlen)
        }
 
        /* mktime uses local timezone */
-       then = my_mktime(&tm);
+       then = tm_to_time_t(&tm);
        if (offset == -1)
                offset = (then - mktime(&tm)) / 60;
 
@@ -611,7 +626,7 @@ void datestamp(char *buf, int bufsize)
 
        time(&now);
 
-       offset = my_mktime(localtime(&now)) - now;
+       offset = tm_to_time_t(localtime(&now)) - now;
        offset /= 60;
 
        date_string(now, offset, buf, bufsize);
@@ -682,10 +697,8 @@ static void date_am(struct tm *tm, int *num)
 
 static void date_never(struct tm *tm, int *num)
 {
-       tm->tm_mon = tm->tm_wday = tm->tm_yday
-               = tm->tm_hour = tm->tm_min = tm->tm_sec = 0;
-       tm->tm_year = 70;
-       tm->tm_mday = 1;
+       time_t n = 0;
+       localtime_r(&n, tm);
 }
 
 static const struct special {
@@ -822,7 +835,9 @@ static const char *approxidate_digit(const char *date, struct tm *tm, int *num)
                }
        }
 
-       *num = number;
+       /* Accept zero-padding only for small numbers ("Dec 02", never "Dec 0002") */
+       if (date[0] != '0' || end - date <= 2)
+               *num = number;
        return end;
 }