From b1cd825cac7ad6139968c3b32c53f4628d73b9a2 Mon Sep 17 00:00:00 2001
From: Xiang Xiao <xiaoxiang@xiaomi.com>
Date: Tue, 22 Jun 2021 00:28:56 +0800
Subject: [PATCH] libc/time: Implement timegm function

Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Change-Id: Id988ae077cf54597b2522546c4309b66416b8b0e
---
 include/time.h                                |  7 +++++--
 libs/libc/time/Make.defs                      |  2 +-
 libs/libc/time/lib_gmtime.c                   |  2 --
 libs/libc/time/lib_gmtimer.c                  |  2 --
 libs/libc/time/lib_localtime.c                |  5 +++++
 libs/libc/time/{lib_mktime.c => lib_timegm.c} | 11 ++++++++---
 6 files changed, 19 insertions(+), 10 deletions(-)
 rename libs/libc/time/{lib_mktime.c => lib_timegm.c} (97%)

diff --git a/include/time.h b/include/time.h
index f0ed66ddb7..e2954577ab 100644
--- a/include/time.h
+++ b/include/time.h
@@ -91,9 +91,10 @@
 
 #define TIME_UTC           1
 
-/* Redirect the timegm */
 
-#define timegm mktime
+/* Redirect the timelocal */
+
+#define timelocal         mktime
 
 /********************************************************************************
  * Public Types
@@ -192,7 +193,9 @@ int clock_gettime(clockid_t clockid, FAR struct timespec *tp);
 int clock_getres(clockid_t clockid, FAR struct timespec *res);
 int timespec_get(FAR struct timespec *t, int b);
 
+time_t timegm(FAR struct tm *tp);
 time_t mktime(FAR struct tm *tp);
+
 FAR struct tm *gmtime(FAR const time_t *timep);
 FAR struct tm *gmtime_r(FAR const time_t *timep, FAR struct tm *result);
 
diff --git a/libs/libc/time/Make.defs b/libs/libc/time/Make.defs
index e74072d5c4..65553c6c1c 100644
--- a/libs/libc/time/Make.defs
+++ b/libs/libc/time/Make.defs
@@ -29,7 +29,7 @@ CSRCS += lib_gethrtime.c
 ifdef CONFIG_LIBC_LOCALTIME
 CSRCS += lib_localtime.c
 else
-CSRCS += lib_mktime.c lib_gmtime.c lib_gmtimer.c
+CSRCS += lib_timegm.c lib_gmtime.c lib_gmtimer.c
 endif
 
 # Add the time directory to the build
diff --git a/libs/libc/time/lib_gmtime.c b/libs/libc/time/lib_gmtime.c
index 780e3f89b0..a474fd86de 100644
--- a/libs/libc/time/lib_gmtime.c
+++ b/libs/libc/time/lib_gmtime.c
@@ -48,9 +48,7 @@ FAR struct tm *gmtime(FAR const time_t *timep)
   return gmtime_r(timep, &tm);
 }
 
-#ifndef CONFIG_LIBC_LOCALTIME
 FAR struct tm *localtime(FAR const time_t *timep)
 {
   return gmtime(timep);
 }
-#endif
diff --git a/libs/libc/time/lib_gmtimer.c b/libs/libc/time/lib_gmtimer.c
index 380d40a439..99a1db0a4b 100644
--- a/libs/libc/time/lib_gmtimer.c
+++ b/libs/libc/time/lib_gmtimer.c
@@ -344,9 +344,7 @@ FAR struct tm *gmtime_r(FAR const time_t *timep, FAR struct tm *result)
   return result;
 }
 
-#ifndef CONFIG_LIBC_LOCALTIME
 FAR struct tm *localtime_r(FAR const time_t *timep, FAR struct tm *result)
 {
   return gmtime_r(timep, result);
 }
-#endif
diff --git a/libs/libc/time/lib_localtime.c b/libs/libc/time/lib_localtime.c
index 99d65d9803..62769e5696 100644
--- a/libs/libc/time/lib_localtime.c
+++ b/libs/libc/time/lib_localtime.c
@@ -2604,3 +2604,8 @@ time_t mktime(struct tm * const tmp)
   tzset();
   return time1(tmp, localsub, 0L);
 }
+
+time_t timegm(FAR struct tm *tmp)
+{
+  return time1(tmp, gmtsub, 0L);
+}
diff --git a/libs/libc/time/lib_mktime.c b/libs/libc/time/lib_timegm.c
similarity index 97%
rename from libs/libc/time/lib_mktime.c
rename to libs/libc/time/lib_timegm.c
index 7d2c02870e..86471d95ad 100644
--- a/libs/libc/time/lib_mktime.c
+++ b/libs/libc/time/lib_timegm.c
@@ -1,5 +1,5 @@
 /****************************************************************************
- * libs/libc/time/lib_mktime.c
+ * libs/libc/time/lib_timegm.c
  *
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
@@ -62,14 +62,14 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name:  mktime
+ * Name:  timegm
  *
  * Description:
  *   Time conversion (based on the POSIX API)
  *
  ****************************************************************************/
 
-time_t mktime(FAR struct tm *tp)
+time_t timegm(FAR struct tm *tp)
 {
   time_t ret;
   time_t jdn;
@@ -90,3 +90,8 @@ time_t mktime(FAR struct tm *tp)
 
   return ret;
 }
+
+time_t mktime(FAR struct tm *tp)
+{
+  return timegm(tp);
+}