Bug 522126, part 3: Use POSIX-clock TimeStamp/TimeDuration implementation if configure.in says it's supported. r=luser

config/autoconf.mk.in

@@ -655,3 +655,6 @@ MOZ_SPLASHSCREEN = @MOZ_SPLASHSCREEN@
 MOZ_THEME_FASTSTRIPE = @MOZ_THEME_FASTSTRIPE@
 
 MOZ_OFFICIAL_BRANDING = @MOZ_OFFICIAL_BRANDING@
+
+HAVE_CLOCK_MONOTONIC = @HAVE_CLOCK_MONOTONIC@
+REALTIME_LIBS = @REALTIME_LIBS@

configure.in

@@ -3600,6 +3600,25 @@ AC_CHECK_FUNCS(random strerror lchown fchmod snprintf statvfs memmove rint stat6
 AC_CHECK_FUNCS(flockfile getpagesize)
 AC_CHECK_FUNCS(localtime_r strtok_r)
 
+dnl check for clock_gettime(), the CLOCK_MONOTONIC clock, and -lrt
+_SAVE_LDFLAGS=$LDFLAGS
+LDFLAGS="$LDFLAGS -lrt"
+AC_CACHE_CHECK(for clock_gettime(CLOCK_MONOTONIC) and -lrt,
+               ac_cv_have_clock_monotonic,
+               [AC_TRY_LINK([#include <time.h>],
+                            [ struct timespec ts;
+                              clock_gettime(CLOCK_MONOTONIC, &ts); ],
+                            ac_cv_have_clock_monotonic=yes,
+                            ac_cv_have_clock_monotonic=no)])
+LDFLAGS=$_SAVE_LDFLAGS
+if test "$ac_cv_have_clock_monotonic" = "yes"; then
+    HAVE_CLOCK_MONOTONIC=1
+    REALTIME_LIBS=-lrt
+    AC_DEFINE(HAVE_CLOCK_MONOTONIC)
+    AC_SUBST(HAVE_CLOCK_MONOTONIC)
+    AC_SUBST(REALTIME_LIBS)
+fi
+
 dnl check for wcrtomb/mbrtowc
 dnl =======================================================================
 if test -z "$MACOS_DEPLOYMENT_TARGET" || test "$MACOS_DEPLOYMENT_TARGET" -ge "100300"; then

toolkit/library/libxul-config.mk

@@ -391,3 +391,7 @@ ifeq ($(OS_ARCH),Linux)
 EXTRA_DSO_LDOPTS += $(MOZ_ALSA_LIBS)
 endif
 endif
+
+ifdef HAVE_CLOCK_MONOTONIC
+EXTRA_DSO_LDOPTS += $(REALTIME_LIBS)
+endif

xpcom/build/Makefile.in

@@ -175,6 +175,10 @@ EXTRA_DSO_LDOPTS += $(LIBHILDONMIME_LIBS)
 endif
 endif
 
+ifdef HAVE_CLOCK_MONOTONIC
+EXTRA_DSO_LDOPTS += $(REALTIME_LIBS)
+endif
+
 ifeq ($(OS_ARCH),WINNT)
 OS_LIBS += $(call EXPAND_LIBNAME,shell32 ole32 uuid version)
 ifneq (,$(MOZ_DEBUG)$(NS_TRACE_MALLOC))

xpcom/ds/Makefile.in

@@ -50,7 +50,6 @@ MOZILLA_INTERNAL_API = 1
 
 
 CPPSRCS		= \
-		TimeStamp.cpp \
 		nsArray.cpp \
 		nsAtomTable.cpp \
 		nsAtomService.cpp \
@@ -77,6 +76,12 @@ CPPSRCS		= \
 		nsVariant.cpp \
 		$(NULL)
 
+ifdef HAVE_CLOCK_MONOTONIC
+CPPSRCS += TimeStamp_posix.cpp
+else
+CPPSRCS += TimeStamp.cpp
+endif
+
 EXPORTS_NAMESPACES = mozilla
 
 EXPORTS_mozilla = \