Add futimes, futimesat and lutimes implementations from bionic

The futimesat function takes an extra argument compared to bionic one:
int flags, due to that unar expects that type of futimesat
function. We can add another futimesat variant (without flags) when it
is needed.

LICENSE.md

@@ -0,0 +1,25 @@
+Copyright (C) 2013 The Android Open Source Project
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met:
+ * Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in
+   the documentation and/or other materials provided with the
+   distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGE.

Makefile

@@ -0,0 +1,20 @@
+CFLAGS += -fpic -shared -std=c11 -Wall -Wextra
+
+all: libandroid-utimes.a libandroid-utimes.so
+libandroid-utimes.a: sys_time.o
+	$(AR) rcu $@ sys_time.o
+
+libandroid-utimes.so: sys_time.o
+	$(CC) $(LDFLAGS) -shared sys_time.c -o $@ -llog
+
+sys_time.o: sys_time.c
+	$(CC) $(CFLAGS) -c sys_time.c -o $@
+
+install: libandroid-utimes.a libandroid-utimes.so
+	install -D libandroid-utimes.a $(DESTDIR)$(PREFIX)/lib/libandroid-utimes.a
+	install -D libandroid-utimes.so $(DESTDIR)$(PREFIX)/lib/libandroid-utimes.so
+
+clean:
+	rm -f libandroid-utimes.a libandroid-utimes.so
+
+.PHONY: install

sys_time.c

@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
+ * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/time.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+
+static int timespec_from_timeval(struct timespec* ts, const struct timeval tv) {
+  // Whole seconds can just be copied.
+  ts->tv_sec = tv.tv_sec;
+
+  // But we might overflow when converting microseconds to nanoseconds.
+  if (tv.tv_usec >= 1000000 || tv.tv_usec < 0) {
+    return 0;
+  }
+  ts->tv_nsec = tv.tv_usec * 1000;
+  return 1;
+}
+
+int futimes(int fd, const struct timeval tv[2]) {
+  struct timespec ts[2];
+  if (tv && (!timespec_from_timeval(&ts[0], tv[0]) || !timespec_from_timeval(&ts[1], tv[1]))) {
+    errno = EINVAL;
+    return -1;
+  }
+  return futimens(fd, tv ? ts : NULL);
+}
+
+int futimesat(int fd, const char* path, const struct timeval tv[2], int flags) {
+  struct timespec ts[2];
+  if (tv && (!timespec_from_timeval(&ts[0], tv[0]) || !timespec_from_timeval(&ts[1], tv[1]))) {
+    errno = EINVAL;
+    return -1;
+  }
+  return utimensat(fd, path, tv ? ts : NULL, flags);
+}
+
+int lutimes(const char* path, const struct timeval tv[2]) {
+  return futimesat(AT_FDCWD, path, tv, AT_SYMLINK_NOFOLLOW);
+}