Kernel/LibC: Implement utime* family functions

This patch adds *working*
 - utime
 - utimes
 - utimensat
 - futimens

userspace/libraries/LibC/sys/stat.cpp

@@ -53,3 +53,13 @@ int mkdir(const char* path, mode_t mode)
 {
 	return syscall(SYS_CREATE_DIR, path, __UMASKED_MODE(mode));
 }
+
+int futimens(int fd, const struct timespec times[2])
+{
+	return utimensat(fd, nullptr, times, 0);
+}
+
+int utimensat(int fd, const char* path, const struct timespec times[2], int flag)
+{
+	return syscall(SYS_UTIMENSAT, fd, path, times, flag);
+}

userspace/libraries/LibC/sys/time.cpp

@@ -1,3 +1,4 @@
+#include <fcntl.h>
 #include <sys/syscall.h>
 #include <sys/time.h>
 #include <time.h>
@@ -26,3 +27,20 @@ int setitimer(int which, const struct itimerval* __restrict value, struct itimer
 {
 	return syscall(SYS_SETITIMER, which, value, ovalue);
 }
+
+int utimes(const char* path, const struct timeval times[2])
+{
+	if (times == nullptr)
+		return utimensat(AT_FDCWD, path, nullptr, 0);
+	const timespec times_ts[2] {
+		timespec {
+			.tv_sec = times[0].tv_sec,
+			.tv_nsec = times[0].tv_usec * 1000,
+		},
+		timespec {
+			.tv_sec = times[1].tv_sec,
+			.tv_nsec = times[1].tv_usec * 1000,
+		},
+	};
+	return utimensat(AT_FDCWD, path, times_ts, 0);
+}