optimization: do not init/link rtc and timezone related functions if never called

Author: uyjulian

ee/libcglue/Makefile

@@ -8,9 +8,16 @@
 
 EE_LIB = libcglue.a
 
-CORE_OBJS = rtc.o
+RTC_OBJS = \
+	_libcglue_rtc_data.o \
+	_libcglue_rtc_get_offset_from_busclk.o \
+	_libcglue_rtc_update.o
 
-TIMEZONE_OBJS = _libcglue_timezone_update.o ps2sdk_setTimezone.o ps2sdk_setDaylightSaving.o
+TIMEZONE_OBJS = \
+	_libcglue_timezone_update_impl.o \
+	_libcglue_timezone_update.o \
+	ps2sdk_setTimezone.o \
+	ps2sdk_setDaylightSaving.o
 
 FDMAN_OBJS = \
 	__fdman_sema.o \
@@ -229,6 +236,7 @@ SOCKET_OBJS = \
 
 EE_OBJS = \
 	$(CORE_OBJS) \
+	$(RTC_OBJS) \
 	$(TIMEZONE_OBJS) \
 	$(SJIS_OBJS) \
 	$(TIME_OBJS) \
@@ -249,6 +257,10 @@ include $(PS2SDKSRC)/ee/Rules.lib.make
 include $(PS2SDKSRC)/ee/Rules.make
 include $(PS2SDKSRC)/ee/Rules.release
 
+$(RTC_OBJS:%=$(EE_OBJS_DIR)%): $(EE_SRC_DIR)rtc.c
+	$(DIR_GUARD)
+	$(EE_C_COMPILE) -DF_$(*:$(EE_OBJS_DIR)%=%) $< -c -o $@
+
 $(TIMEZONE_OBJS:%=$(EE_OBJS_DIR)%): $(EE_SRC_DIR)timezone.c
 	$(DIR_GUARD)
 	$(EE_C_COMPILE) -DF_$(*:$(EE_OBJS_DIR)%=%) $< -c -o $@

ee/libcglue/include/ps2sdkapi.h

@@ -175,6 +175,8 @@ static inline ps2_clock_t ps2_clock(void) {
 }
 
 extern s64 _ps2sdk_rtc_offset_from_busclk;
+s64 _libcglue_rtc_get_offset_from_busclk(void);
+extern void _libcglue_rtc_update_impl();
 extern void _libcglue_rtc_update();
 
 // The newlib port does not support 64bit
@@ -183,6 +185,7 @@ typedef int64_t off64_t;
 extern off64_t lseek64(int fd, off64_t offset, int whence);
 
 // Functions to be used related to timezone
+extern void _libcglue_timezone_update_impl();
 extern void _libcglue_timezone_update();
 
 extern void ps2sdk_setTimezone(int timezone);

ee/libcglue/src/glue.c

@@ -788,7 +788,7 @@ int _gettimeofday(struct timeval *tv, struct timezone *tz)
 		u32 busclock_usec;
 
 		TimerBusClock2USec(GetTimerSystemTime(), &busclock_sec, &busclock_usec);
-		tv->tv_sec = (time_t)(_ps2sdk_rtc_offset_from_busclk + ((s64)busclock_sec));
+		tv->tv_sec = (time_t)(_libcglue_rtc_get_offset_from_busclk() + ((s64)busclock_sec));
 		tv->tv_usec = busclock_usec;
 	}
 

ee/libcglue/src/rtc.c

@@ -24,10 +24,17 @@
 // The definition for this function is located in ee/rpc/cdvd/src/scmd.c
 extern time_t ps2time(time_t *t);
 
+#ifdef F__libcglue_rtc_data
 s64 _ps2sdk_rtc_offset_from_busclk = 0;
+#endif
 
-__attribute__((weak))
-void _libcglue_rtc_update()
+#ifdef F__libcglue_rtc_get_offset_from_busclk
+s64 _libcglue_rtc_get_offset_from_busclk(void)
+{
+	return _ps2sdk_rtc_offset_from_busclk;
+}
+
+void _libcglue_rtc_update_impl()
 {
 	time_t rtc_sec;
 	u32 busclock_sec;
@@ -38,3 +45,17 @@ void _libcglue_rtc_update()
 
 	_ps2sdk_rtc_offset_from_busclk = ((s64)rtc_sec) - ((s64)busclock_sec);
 }
+#endif
+
+#ifdef F__libcglue_rtc_update
+void __attribute__((weak)) _libcglue_rtc_update_impl();
+__attribute__((weak))
+void _libcglue_rtc_update()
+{
+	// cppcheck-suppress knownConditionTrueFalse
+	if (&_libcglue_rtc_update_impl)
+	{
+		_libcglue_rtc_update_impl();
+	}
+}
+#endif

ee/libcglue/src/timezone.c

@@ -18,16 +18,16 @@
 #include <stdlib.h>
 #include <unistd.h>
 #include <fcntl.h>
+#include <reent.h>
 
 #include <ps2sdkapi.h>
 #define OSD_CONFIG_NO_LIBCDVD
 #include "osd_config.h"
 
 #define posixIODriver { open, close, (int (*)(int, void *, int))read, O_RDONLY }
 
-#ifdef F__libcglue_timezone_update
-__attribute__((weak))
-void _libcglue_timezone_update()
+#ifdef F__libcglue_timezone_update_impl
+void _libcglue_timezone_update_impl()
 {
     /* Initialize timezone from PS2 OSD configuration */
 	_io_driver driver = posixIODriver;
@@ -45,6 +45,20 @@ void _libcglue_timezone_update()
 }
 #endif
 
+#ifdef F__libcglue_timezone_update
+// Defined in newlib: newlib/libc/time/tzset_r.c
+void __attribute((weak)) _tzset_unlocked_r(struct _reent *reent_ptr);
+__attribute__((weak))
+void _libcglue_timezone_update()
+{
+	// cppcheck-suppress knownConditionTrueFalse
+	if (&_tzset_unlocked_r)
+	{
+		_libcglue_timezone_update_impl();
+	}
+}
+#endif
+
 #ifdef F_ps2sdk_setTimezone
 void ps2sdk_setTimezone(int timezone) {
 	_io_driver driver = posixIODriver;