Introduce cosmo_futex_wait and cosmo_futex_wake

Cosmopolitan Futexes are now exposed as a public API.

Author: jart

libc/calls/sig.c

@@ -1,5 +1,6 @@
 #ifndef COSMOPOLITAN_LIBC_COSMO_H_
 #define COSMOPOLITAN_LIBC_COSMO_H_
+#include "libc/calls/struct/timespec.h"
 COSMOPOLITAN_C_START_
 
 #ifndef __cplusplus
@@ -17,6 +18,9 @@ int __is_mangled(const char *) libcesque;
 bool32 IsLinuxModern(void) libcesque;
 int LoadZipArgs(int *, char ***) libcesque;
 int cosmo_args(const char *, char ***) libcesque;
+int cosmo_futex_wake(_COSMO_ATOMIC(int) *, int, char);
+int cosmo_futex_wait(_COSMO_ATOMIC(int) *, int, char, int,
+                     const struct timespec *);
 
 COSMOPOLITAN_C_END_
 #endif /* COSMOPOLITAN_LIBC_COSMO_H_ */

libc/cosmo.h

@@ -30,9 +30,11 @@ LIBC_INTRIN_A_CHECKS =					\
 LIBC_INTRIN_A_DIRECTDEPS =				\
 	LIBC_NEXGEN32E					\
 	LIBC_NT_KERNEL32				\
+	LIBC_NT_REALTIME				\
+	LIBC_NT_SYNCHRONIZATION				\
 	LIBC_NT_WS2_32					\
 	LIBC_SYSV					\
-	LIBC_SYSV_CALLS
+	LIBC_SYSV_CALLS					\
 
 LIBC_INTRIN_A_DEPS :=					\
 	$(call uniq,$(foreach x,$(LIBC_INTRIN_A_DIRECTDEPS),$($(x))))
@@ -106,6 +108,16 @@ o//libc/intrin/demangle.o: private			\
 		CFLAGS +=				\
 			-mgeneral-regs-only
 
+# ensure that division is optimized
+o/$(MODE)/libc/intrin/windowsdurationtotimeval.o	\
+o/$(MODE)/libc/intrin/windowsdurationtotimespec.o	\
+o/$(MODE)/libc/intrin/timevaltowindowstime.o		\
+o/$(MODE)/libc/intrin/timespectowindowstime.o		\
+o/$(MODE)/libc/intrin/windowstimetotimeval.o		\
+o/$(MODE)/libc/intrin/windowstimetotimespec.o: private	\
+		CFLAGS +=				\
+			-O2
+
 # these assembly files are safe to build on aarch64
 o/$(MODE)/libc/intrin/aarch64/%.o: libc/intrin/aarch64/%.S
 	@$(COMPILE) -AOBJECTIFY.S $(OBJECTIFY.S) $(OUTPUT_OPTION) -c $<