Added support for timezones, hence localtime() will now return actual localtime. Added timeToCalendarTimeWithMyRule and TimeCalendarTime/TimeCalendarAdditionalInfo, which are used for timezones support.

nx/include/switch/services/time.h

@@ -17,6 +17,24 @@ typedef enum {
     TimeType_Default = TimeType_UserSystemClock,
 } TimeType;
 
+typedef struct {
+    u16 year;
+    u8 month;
+    u8 day;
+    u8 hour;
+    u8 minute;
+    u8 second;
+    u8 pad;
+} TimeCalendarTime;
+
+typedef struct {
+    u32 wday; ///< 0-based day-of-week.
+    u32 yday; ///< 0-based day-of-year.
+    char timezoneName[8]; ///< Timezone name string.
+    u32 DST; ///< 0 = no DST, 1 = DST.
+    s32 offset; ///< Seconds relative to UTC for this timezone.
+} TimeCalendarAdditionalInfo;
+
 Result timeInitialize(void);
 void timeExit(void);
 
@@ -31,3 +49,6 @@ Result timeGetCurrentTime(TimeType type, u64 *timestamp);
  * @return Result code.
  */
 Result timeSetCurrentTime(TimeType type, u64 timestamp);
+
+Result timeToCalendarTimeWithMyRule(u64 timestamp, TimeCalendarTime *caltime, TimeCalendarAdditionalInfo *info);
+

nx/source/runtime/newlib.c

@@ -1,6 +1,8 @@
 #include <string.h>
 #include <errno.h>
 #include <stdint.h>
+#include <stdlib.h>
+#include <stdio.h>
 #include <sys/iosupport.h>
 #include <sys/time.h>
 #include <sys/lock.h>
@@ -31,12 +33,17 @@ static struct _reent* __libnx_get_reent(void) {
     return tv->reent;
 }
 
-//TODO: timeGetCurrentTime() returns UTC time. How to handle timezones?
 static u64 __boottime;
 static u64 __bootticks;
 
 // setup boot time variables
 void __libnx_init_time(void) {
+    TimeCalendarAdditionalInfo info;
+    char envstr[64];
+    char *strptr;
+    bool is_west=0;
+    s32 tmp_offset, hour, minute, second;
+
     Result rc =  timeGetCurrentTime(__nx_time_type, &__boottime);
     if (R_FAILED(rc) && __nx_time_type != TimeType_Default) rc =  timeGetCurrentTime(TimeType_Default, &__boottime);
     if (R_FAILED(rc)) {
@@ -44,6 +51,43 @@ void __libnx_init_time(void) {
     } else {
         __bootticks = armGetSystemTick();
     }
+
+    if (R_SUCCEEDED(rc)) rc = timeToCalendarTimeWithMyRule(__boottime, NULL, &info);
+
+    if (R_SUCCEEDED(rc)) {
+        info.timezoneName[7] = 0;
+        tmp_offset = info.offset;
+        if (tmp_offset < 0) {
+            is_west = 1;
+            tmp_offset = -tmp_offset;
+        }
+
+        second = tmp_offset % 60;
+        tmp_offset /= 60;
+        minute = tmp_offset % 60;
+        tmp_offset /= 60;
+        hour = tmp_offset % 24;
+
+        memset(envstr, 0, sizeof(envstr));
+
+        //Avoid using *printf.
+        strncpy(envstr, info.timezoneName, sizeof(envstr)-1);
+        strptr = &envstr[strlen(envstr)];
+        *strptr++ = is_west ? '+' : '-';
+
+        *strptr++ = '0' + (hour / 10);
+        *strptr++ = '0' + (hour % 10);
+        *strptr++ = ':';
+
+        *strptr++ = '0' + (minute / 10);
+        *strptr++ = '0' + (minute % 10);
+        *strptr++ = ':';
+
+        *strptr++ = '0' + (second / 10);
+        *strptr++ = '0' + (second % 10);
+
+        setenv("TZ", envstr, 0);
+    }
 }
 
 static const u64 nsec_clockres =  1000000000ULL / 19200000ULL;

nx/source/services/time.c

@@ -191,3 +191,41 @@ Result timeSetCurrentTime(TimeType type, u64 timestamp) {
     return rc;
 }
 
+Result timeToCalendarTimeWithMyRule(u64 timestamp, TimeCalendarTime *caltime, TimeCalendarAdditionalInfo *info) {
+    IpcCommand c;
+    ipcInitialize(&c);
+
+    struct {
+        u64 magic;
+        u64 cmd_id;
+        u64 timestamp;
+    } *raw;
+
+    raw = ipcPrepareHeader(&c, sizeof(*raw));
+
+    raw->magic = SFCI_MAGIC;
+    raw->cmd_id = 101;
+    raw->timestamp = timestamp;
+
+    Result rc = serviceIpcDispatch(&g_timeTimeZoneService);
+
+    if (R_SUCCEEDED(rc)) {
+        IpcParsedCommand r;
+        ipcParse(&r);
+
+        struct {
+            u64 magic;
+            u64 result;
+            TimeCalendarTime caltime;
+            TimeCalendarAdditionalInfo info;
+        } *resp = r.Raw;
+
+        rc = resp->result;
+
+        if (R_SUCCEEDED(rc) && caltime) memcpy(caltime, &resp->caltime, sizeof(TimeCalendarTime));
+        if (R_SUCCEEDED(rc) && info) memcpy(info, &resp->info, sizeof(TimeCalendarAdditionalInfo));
+    }
+
+    return rc;
+}
+