From 4fe5b1d77bc60d2a44c7fcd9a0b7d66d0035cdea Mon Sep 17 00:00:00 2001 From: Corinna Vinschen Date: Wed, 21 Feb 2024 19:54:20 +0100 Subject: [PATCH] Cygwin: strptime: fix am/pm handling The %p format specifier is handled immediately. It requires that tm_hour is already set. This falls flat in case the am/pm marker preceeds the time specification. Locales with am/pm marker preceeding time spec by default exist (e. g. ko_KR). Also, the code expects that tm_hour might be set to an invalid value because the %p specifier is used in conjunction with %H. But this usage is invalid in itself and now catched as error condition after commit 343a2a558153 ("Cygwin: strptime: make sure to fail on invalid input digits"). Change the %H/%I/%p handling according to GLibC, i. e. - fix tm_hour for pm only if the time value has been specified as 12 hour time %I, and - perform the fixup only after the entire input has been scanned. This decouples the fixup from the %p position relativ to %I. Signed-off-by: Corinna Vinschen --- winsup/cygwin/libc/strptime.cc | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/winsup/cygwin/libc/strptime.cc b/winsup/cygwin/libc/strptime.cc index 353b8008a..dc6771fe5 100644 --- a/winsup/cygwin/libc/strptime.cc +++ b/winsup/cygwin/libc/strptime.cc @@ -335,6 +335,8 @@ __strptime(const char *buf, const char *fmt, struct tm *tm, const char *new_fmt; uint ulim; int ymd = 0; + bool got_I = false; + bool got_pm = false; bp = (const unsigned char *)buf; const struct lc_time_T *_CurrentTimeLocale = __get_time_locale (locale); @@ -537,6 +539,7 @@ literal: case 'H': LEGAL_ALT(ALT_O); bp = conv_num(bp, &tm->tm_hour, 0, 23, ALT_DIGITS); + got_I = false; continue; case 'l': /* The hour (12-hour clock representation). */ @@ -547,6 +550,7 @@ literal: bp = conv_num(bp, &tm->tm_hour, 1, 12, ALT_DIGITS); if (tm->tm_hour == 12) tm->tm_hour = 0; + got_I = true; continue; case 'j': /* The day of year. */ @@ -573,9 +577,7 @@ literal: case 'p': /* The locale's equivalent of AM/PM. */ bp = find_string(bp, &i, _ctloc(am_pm), NULL, 2, locale); - if (tm->tm_hour > 11) - return NULL; - tm->tm_hour += i * 12; + got_pm = (i == 1); LEGAL_ALT(0); continue; @@ -751,8 +753,12 @@ literal: default: /* Unknown/unsupported conversion. */ return NULL; } + } + if (got_I && got_pm) + tm->tm_hour += 12; + if (bp && (era || got_eoff)) { /* Default to current era. */