sync: support syncing specified arguments

* m4/jm-macros.m4 (coreutils_MACROS): Check for syncfs().
* man/sync.x: Add references to syncfs, fsync and fdatasync.
* doc/coreutils.texi (sync invocation): Document the new feature.
* src/sync.c: Include "quote.h".
(AUTHORS): Include myself.
(MODE_FILE, MODE_DATA, MODE_FILE_SYSTEM, MODE_SYNC): New enum values.
(long_options): Define.
(sync_arg): New function.
(usage): Describe that arguments are now accepted.
(main): Add arguments parsing and add support for fsync(2),
fdatasync(2) and syncfs(2).
* tests/misc/sync.sh: New (and only) test for sync.
* tests/local.mk: Reference the new test.
* AUTHORS: Add myself to sync's authors.
* NEWS: Mention the new feature.

2 files changed, 51 insertions, 0 deletions

diff --git a/tests/local.mk b/tests/local.mk
index 5dcbd5595..bfa447c7d 100644
--- a/tests/local.mk
+++ b/tests/local.mk
@@ -375,6 +375,7 @@ all_tests =					\
   tests/misc/stty-row-col.sh			\
   tests/misc/sum.pl				\
   tests/misc/sum-sysv.sh			\
+  tests/misc/sync.sh				\
   tests/misc/tac.pl				\
   tests/misc/tac-continue.sh			\
   tests/misc/tac-2-nonseekable.sh		\
diff --git a/tests/misc/sync.sh b/tests/misc/sync.sh
new file mode 100755
index 000000000..a20463061
--- /dev/null
+++ b/tests/misc/sync.sh
@@ -0,0 +1,50 @@
+#!/bin/sh
+# Test various sync(1) operations
+
+# Copyright (C) 2015 Free Software Foundation, Inc.
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 3 of the License, or
+# (at your option) any later version.
+
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
+print_ver_ sync
+
+touch file
+
+# fdatasync+syncfs is nonsensical
+returns_ 1 sync --data --file-system || fail=1
+
+# fdatasync needs an operand
+returns_ 1 sync -d || fail=1
+
+# Test syncing of file (fsync) (little side effects)
+sync file || fail=1
+
+# Ensure multiple args are processed and diagnosed
+returns_ 1 sync file nofile || fail=1
+
+# Ensure inaccessible dirs give an appropriate error
+mkdir norw || framework_failure_
+chmod 0 norw || framework_failure_
+sync norw 2>err
+printf "sync: error opening 'norw': Permission denied\n" >exp
+compare exp err || fail=1
+
+if test "$fail" != '1'; then
+  # Ensure a fifo doesn't block
+  mkfifo_or_skip_ fifo
+  timeout 10 sync fifo
+  test $? = 124 && fail=1
+fi
+
+Exit $fail