win32: changes to allow timezones in dates

Create mingw_strptime() to return timezone offset as a separate
argument (since Microsoft's struct tm doesn't have the required
member).

Import timegm() from musl.

Update parse_datestr() to use mingw_strptime().

Enable FEATURE_TIMEZONE in the default configuration.

GitHub issue #230.

1 files changed, 9 insertions, 0 deletions

diff --git a/libbb/time.c b/libbb/time.c
index 41a69c754..ed4f50470 100644
--- a/libbb/time.c
+++ b/libbb/time.c
@@ -43,7 +43,12 @@ int FAST_FUNC parse_datestr(const char *date_str, struct tm *ptm)
         save = *ptm;
         fmt = fmt_str;
         while (*fmt) {
+#if ENABLE_PLATFORM_MINGW32 && ENABLE_FEATURE_TIMEZONE
+                long gmtoff;
+                endp = mingw_strptime(date_str, fmt, ptm, &gmtoff);
+#else
                 endp = strptime(date_str, fmt, ptm);
+#endif
                 if (endp && *endp == '\0') {
 #if ENABLE_FEATURE_TIMEZONE
                         if (strchr(fmt, 'z')) {
@@ -51,7 +56,11 @@ int FAST_FUNC parse_datestr(const char *date_str, struct tm *ptm)
                                 struct tm *utm;
 
                                 /* we have timezone offset: obtain Unix time_t */
+#if ENABLE_PLATFORM_MINGW32
+                                ptm->tm_sec -= gmtoff;
+#else
                                 ptm->tm_sec -= ptm->tm_gmtoff;
+#endif
                                 ptm->tm_isdst = 0;
                                 t = timegm(ptm);
                                 if (t == (time_t)-1)