From e8ef801a3eb85e4f028218de89653caff7f2695b Mon Sep 17 00:00:00 2001
From: Vicki Pfau <vi@endrift.com>
Date: Wed, 12 Apr 2023 03:33:39 -0700
Subject: [PATCH] Vita: Work around broken mktime implementation in Vita SDK
 (fixes #2876)

---
 CHANGES                          |  1 +
 src/gba/savedata.c               | 41 +++++++++++++++++++++++++++++++-
 src/platform/psp2/CMakeLists.txt |  1 +
 3 files changed, 42 insertions(+), 1 deletion(-)

diff --git a/CHANGES b/CHANGES
index 03d763dcc..3601b0fd9 100644
--- a/CHANGES
+++ b/CHANGES
@@ -33,6 +33,7 @@ Other fixes:
  - Scripting: Fix receiving packets for client sockets
  - Scripting: Fix empty receive calls returning unknown error on Windows
  - Scripting: Return proper callback ID from socket.add
+ - Vita: Work around broken mktime implementation in Vita SDK (fixes mgba.io/i/2876)
 Misc:
  - Core: Handle relative paths for saves, screenshots, etc consistently (fixes mgba.io/i/2826)
  - GB Serialize: Add missing savestate support for MBC6 and NT (newer)
diff --git a/src/gba/savedata.c b/src/gba/savedata.c
index 2d377a875..512af02c9 100644
--- a/src/gba/savedata.c
+++ b/src/gba/savedata.c
@@ -13,6 +13,10 @@
 #include <mgba-util/memory.h>
 #include <mgba-util/vfs.h>
 
+#ifdef PSP2
+#include <psp2/rtc.h>
+#endif
+
 #include <errno.h>
 #include <fcntl.h>
 
@@ -637,6 +641,9 @@ void GBASavedataRTCRead(struct GBASavedata* savedata) {
 	}
 	LOAD_64LE(savedata->gpio->rtc.lastLatch, 0, &buffer.lastLatch);
 
+	time_t rtcTime;
+
+#ifndef PSP2
 	struct tm date;
 	date.tm_year = _unBCD(savedata->gpio->rtc.time[0]) + 100;
 	date.tm_mon = _unBCD(savedata->gpio->rtc.time[1]) - 1;
@@ -645,8 +652,40 @@ void GBASavedataRTCRead(struct GBASavedata* savedata) {
 	date.tm_min = _unBCD(savedata->gpio->rtc.time[5]);
 	date.tm_sec = _unBCD(savedata->gpio->rtc.time[6]);
 	date.tm_isdst = -1;
+	rtcTime = mktime(&date);
+#else
+	struct SceDateTime date;
+	date.year = _unBCD(savedata->gpio->rtc.time[0]) + 2000;
+	date.month = _unBCD(savedata->gpio->rtc.time[1]);
+	date.day = _unBCD(savedata->gpio->rtc.time[2]);
+	date.hour = _unBCD(savedata->gpio->rtc.time[4]);
+	date.minute = _unBCD(savedata->gpio->rtc.time[5]);
+	date.second = _unBCD(savedata->gpio->rtc.time[6]);
+	date.microsecond = 0;
 
-	savedata->gpio->rtc.offset = savedata->gpio->rtc.lastLatch - mktime(&date);
+	struct SceRtcTick tick;
+	int res;
+	res = sceRtcConvertDateTimeToTick(&date, &tick);
+	if (res < 0) {
+		mLOG(GBA_SAVE, ERROR, "sceRtcConvertDateTimeToTick %lx", res);
+	}
+	res = sceRtcConvertLocalTimeToUtc(&tick, &tick);
+	if (res < 0) {
+		mLOG(GBA_SAVE, ERROR, "sceRtcConvertUtcToLocalTime %lx", res);
+	}
+	res = sceRtcConvertTickToDateTime(&tick, &date);
+	if (res < 0) {
+		mLOG(GBA_SAVE, ERROR, "sceRtcConvertTickToDateTime %lx", res);
+	}
+	res = sceRtcConvertDateTimeToTime_t(&date, &rtcTime);
+	if (res < 0) {
+		mLOG(GBA_SAVE, ERROR, "sceRtcConvertDateTimeToTime_t %lx", res);
+	}
+#endif
+
+	savedata->gpio->rtc.offset = savedata->gpio->rtc.lastLatch - rtcTime;
+
+	mLOG(GBA_SAVE, ERROR, "Savegame time offset set to %li", savedata->gpio->rtc.offset);
 }
 
 void GBASavedataSerialize(const struct GBASavedata* savedata, struct GBASerializedState* state) {
diff --git a/src/platform/psp2/CMakeLists.txt b/src/platform/psp2/CMakeLists.txt
index fa9847f14..3e638aa64 100644
--- a/src/platform/psp2/CMakeLists.txt
+++ b/src/platform/psp2/CMakeLists.txt
@@ -28,6 +28,7 @@ set(OS_LIB -lvita2d -l${M_LIBRARY}
     -lScePgf_stub
     -lScePhotoExport_stub
     -lScePower_stub
+    -lSceRtc_stub
     -lSceSysmodule_stub
     -lSceTouch_stub)
 set(OS_LIB ${OS_LIB} PARENT_SCOPE)