Add rtc-day/hour options to override NDS clock

--rtc-day and --rtc-hour may be used to override the emulated time.
rtc-day is a day of week (0-6) rtc-hour is the hour (0-23). Time
difference is calculated at emulator start and the emulated RTC then
reports time from the future. This difference is then maintained so that
an hour after the emulator is started means an hour passes according
to the RTC.

desmume/src/commandline.cpp

@@ -22,9 +22,11 @@
 #include "commandline.h"
 #include "types.h"
 #include "movie.h"
+#include "rtc.h"
 #include "slot1.h"
 #include "slot2.h"
 #include "NDSSystem.h"
+#include "utils/datetime.h"
 #include "utils/xstring.h"
 #include <compat/getopt.h>
 //#include "frontend/modules/mGetOpt.h" //to test with this, make sure global `optind` is initialized to 1
@@ -74,6 +76,8 @@ CommandLine::CommandLine()
 , language(1) //english by default
 , disable_sound(0)
 , disable_limiter(0)
+, _rtc_day(-1)
+, _rtc_hour(-1)
 {
 }
 
@@ -116,6 +120,8 @@ static const char* help_string = \
 #endif
 " --disable-sound            Disables the sound output" ENDL
 " --disable-limiter          Disables the 60fps limiter" ENDL
+" --rtc-day D                Override RTC day, 0=Sunday, 6=Saturday" ENDL
+" --rtc-hour H               Override RTC hour, 0=midnight, 23=an hour before" ENDL
 ENDL
 "Arguments affecting overall emulation parameters (`sync settings`): " ENDL
 #ifdef HAVE_JIT
@@ -206,6 +212,9 @@ ENDL
 #define OPT_ARM9GDB 700
 #define OPT_ARM7GDB 701
 
+#define OPT_RTC_DAY 800
+#define OPT_RTC_HOUR 801
+
 #define OPT_ADVANSCENE 900
 
 bool CommandLine::parse(int argc,char **argv)
@@ -237,6 +246,8 @@ bool CommandLine::parse(int argc,char **argv)
 			#endif
 			{ "disable-sound", no_argument, &disable_sound, 1},
 			{ "disable-limiter", no_argument, &disable_limiter, 1},
+			{ "rtc-day", required_argument, NULL, OPT_RTC_DAY},
+			{ "rtc-hour", required_argument, NULL, OPT_RTC_HOUR},
 
 			//sync settings
 			#ifdef HAVE_JIT
@@ -306,6 +317,10 @@ bool CommandLine::parse(int argc,char **argv)
 		case OPT_3D_TEXTURE_UPSCALE: texture_upscale = atoi(optarg); break;
 		case OPT_GPU_RESOLUTION_MULTIPLIER: gpu_resolution_multiplier = atoi(optarg); break;
 
+		//RTC settings
+		case OPT_RTC_DAY: _rtc_day = atoi(optarg); break;
+		case OPT_RTC_HOUR: _rtc_hour = atoi(optarg); break;
+
 		//sync settings
 		case OPT_JIT_SIZE: _jit_size = atoi(optarg); break;
 
@@ -497,6 +512,14 @@ bool CommandLine::validate()
 		printerror("Invalid jit block size [1..100]. set to 100\n");
 	}
 #endif
+        if (_rtc_day < -1 || _rtc_day > 6) {
+                printerror("Invalid rtc day override, valid values are from 0 to 6");
+                return false;
+        }
+        if (_rtc_hour < -1 || _rtc_hour > 23) {
+                printerror("Invalid rtc day override, valid values are from 0 to 23");
+                return false;
+        }
 
 	return true;
 }
@@ -548,5 +571,19 @@ void CommandLine::process_addonCommands()
 			slot1_Change(NDS_SLOT1_RETAIL_MCROM);
 			else if(slot1 == "RETAILDEBUG")
 				slot1_Change(NDS_SLOT1_RETAIL_DEBUG);
+
+        if (_rtc_day != -1 || _rtc_hour != -1) {
+                DateTime now = DateTime::get_Now();
+                int cur_day = now.get_DayOfWeek();
+                int cur_hour = now.get_Hour();
+                int cur_total = cur_day * 24 + cur_hour;
+                int day = (_rtc_day != -1 ? _rtc_day : cur_day);
+                int hour = (_rtc_hour != -1 ? _rtc_hour : cur_hour);
+                int total = day * 24 + hour;
+                int diff = total - cur_total;
+                if (diff < 0)
+                        diff += 24 * 7;
+                rtcHourOverride = diff;
+        }
 }
 

desmume/src/commandline.h

@@ -107,6 +107,8 @@ private:
 	char *_slot1_fat_dir;
 	char* _console_type;
 	char* _advanscene_import;
+	int _rtc_day;
+	int _rtc_hour;
 };
 
 #endif

desmume/src/rtc.cpp

@@ -29,6 +29,7 @@
 #endif
 #include "movie.h"
 
+int rtcHourOverride = 0;
 
 typedef struct
 {
@@ -95,9 +96,8 @@ bool moviemode=false;
 
 DateTime rtcGetTime(void)
 {
-	DateTime tm;
 	if(movieMode == MOVIEMODE_INACTIVE) {
-		return DateTime::get_Now();
+		return DateTime::get_Now().AddHours(rtcHourOverride);
 	}
 	else {
 		//now, you might think it is silly to go through all these conniptions

desmume/src/rtc.h

@@ -24,6 +24,8 @@
 #include "types.h"
 #include "utils/datetime.h"
 
+extern int rtcHourOverride;
+
 DateTime rtcGetTime(void);
 void rtcGetTimeAsString(char *buffer);