linux,darwin: make uv_fs_copyfile behaves like cp -r (libuv#4396)

This commit changes the timestamps in the file, the ownership and the
group.

Fixes: libuv#3125

Signed-off-by: Juan José Arboleda <soyjuanarbol@gmail.com>

src/unix/fs.c

@@ -1233,6 +1233,7 @@ static ssize_t uv__fs_copyfile(uv_fs_t* req) {
   uv_file dstfd;
   struct stat src_statsbuf;
   struct stat dst_statsbuf;
+  struct timespec times[2];
   int dst_flags;
   int result;
   int err;
@@ -1310,6 +1311,29 @@ static ssize_t uv__fs_copyfile(uv_fs_t* req) {
     }
   }
 
+  /**
+   * Change the timestamps of the destination file to match the source file.
+   */
+#if defined(__APPLE__)
+  times[0] = src_statsbuf.st_atimespec;
+  times[1] = src_statsbuf.st_mtimespec;
+#else
+  times[0] = src_statsbuf.st_atim;
+  times[1] = src_statsbuf.st_mtim;
+#endif
+
+  if (futimens(dstfd, times) == -1) {
+    err = UV__ERR(errno);
+    goto out;
+  }
+
+  /*
+   * Change the ownership and permissions of the destination file to match the
+   * source file.
+   * `cp -p` does not care about errors here, so we don't either.
+   */
+  fchown(dstfd, src_statsbuf.st_uid, src_statsbuf.st_gid);
+
   if (fchmod(dstfd, src_statsbuf.st_mode) == -1) {
     err = UV__ERR(errno);
 #ifdef __linux__

test/test-fs-copyfile.c

@@ -46,6 +46,8 @@ static void handle_result(uv_fs_t* req) {
   uv_fs_t stat_req;
   uint64_t size;
   uint64_t mode;
+  uint64_t uid;
+  uint64_t gid;
   int r;
 
   ASSERT_EQ(req->fs_type, UV_FS_COPYFILE);
@@ -56,11 +58,15 @@ static void handle_result(uv_fs_t* req) {
   ASSERT_OK(r);
   size = stat_req.statbuf.st_size;
   mode = stat_req.statbuf.st_mode;
+  uid = stat_req.statbuf.st_uid;
+  gid = stat_req.statbuf.st_gid;
   uv_fs_req_cleanup(&stat_req);
   r = uv_fs_stat(NULL, &stat_req, dst, NULL);
   ASSERT_OK(r);
   ASSERT_EQ(stat_req.statbuf.st_size, size);
   ASSERT_EQ(stat_req.statbuf.st_mode, mode);
+  ASSERT_EQ(stat_req.statbuf.st_uid, uid);
+  ASSERT_EQ(stat_req.statbuf.st_gid, gid);
   uv_fs_req_cleanup(&stat_req);
   uv_fs_req_cleanup(req);
   result_check_count++;