>From e6e98c91b94f8bde4bd4b9a7ebc0a670695a1e42 Mon Sep 17 00:00:00 2001
From: Pavel Raiskup <address@hidden>
Date: Thu, 13 Mar 2014 08:58:42 +0100
Subject: [PATCH] tar: fail if archive comes directly from terminal

References:
http://lists.gnu.org/archive/html/bug-tar/2014-03/msg00037.html

* src/buffer.c (_open_archive): Call avoid_terminal_io ().
(avoid_terminal_io): New function; fails if isatty(archive).
* tests/iotty.at: New testcase.
* tests/Makefile.am: Handle new testcase.
* tests/testsuite.at: Handle new testcase and define new macro
AT_SCRIPT_PREREQ.
---
 src/buffer.c       | 18 ++++++++++++++++++
 tests/Makefile.am  |  1 +
 tests/iotty.at     | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 tests/testsuite.at |  7 +++++++
 4 files changed, 72 insertions(+)
 create mode 100644 tests/iotty.at

diff --git a/src/buffer.c b/src/buffer.c
index 95e8a26..f2f56cb 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -668,6 +668,22 @@ init_buffer (void)
   record_end = record_start + blocking_factor;
 }
 
+static void
+avoid_terminal_io (enum access_mode wanted_access)
+{
+  if (0 != strcmp (archive_name_array[0], "-"))
+    return;
+
+  /* do not fail if the tar's output goes directly to tty because such
+     behavior would go against GNU Coding Standards:
+     http://lists.gnu.org/archive/html/bug-tar/2014-03/msg00042.html */
+  if (wanted_access == ACCESS_READ
+      && isatty (STDIN_FILENO))
+    FATAL_ERROR ((0, 0,
+                  _("I won't read archive contents from terminal "
+                    "(missing -f option?)")));
+}
+
 /* Open an archive file.  The argument specifies whether we are
    reading or writing, or both.  */
 static void
@@ -689,6 +705,8 @@ _open_archive (enum access_mode wanted_access)
   /* When updating the archive, we start with reading.  */
   access_mode = wanted_access == ACCESS_UPDATE ? ACCESS_READ : wanted_access;
 
+  avoid_terminal_io (access_mode);
+
   read_full_records = read_full_records_option;
 
   records_read = 0;
diff --git a/tests/Makefile.am b/tests/Makefile.am
index d4c9362..0ab28c8 100644
--- a/tests/Makefile.am
+++ b/tests/Makefile.am
@@ -116,6 +116,7 @@ TESTSUITE_AT = \
  incr09.at\
  indexfile.at\
  ignfail.at\
+ iotty.at\
  label01.at\
  label02.at\
  label03.at\
diff --git a/tests/iotty.at b/tests/iotty.at
new file mode 100644
index 0000000..5aae1d3
--- /dev/null
+++ b/tests/iotty.at
@@ -0,0 +1,46 @@
+# Process this file with autom4te to create testsuite. -*- Autotest -*-
+
+# Test suite for GNU tar.
+# Copyright 2014 Free Software Foundation, Inc.
+
+# This file is part of GNU tar.
+
+# GNU tar 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.
+
+# GNU tar 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/>.
+
+# Ensure that we may not put/read archive contents to/from terminal
+# output/input.
+#
+# Original report:
+# http://lists.gnu.org/archive/html/bug-tar/2014-03/msg00033.html
+
+AT_SETUP([terminal input/output])
+AT_KEYWORDS([options iotty])
+
+AT_TAR_CHECK([
+AT_SCRIPT_PREREQ
+AT_GZIP_PREREQ
+genfile --file file
+script -q -c "tar -x"           /dev/null >> out
+script -q -c "tar -xz"          /dev/null >> out
+cat out | sed 's|\r||'
+],
+[0],
+[tar: I won't read archive contents from terminal (missing -f option?)
+tar: Error is not recoverable: exiting now
+tar: I won't read archive contents from terminal (missing -f option?)
+tar: Error is not recoverable: exiting now
+],
+[],[],[],[posix, gnu, oldgnu])
+
+AT_CLEANUP
diff --git a/tests/testsuite.at b/tests/testsuite.at
index c52890b..2011e4a 100644
--- a/tests/testsuite.at
+++ b/tests/testsuite.at
@@ -124,6 +124,12 @@ m4_define([AT_CHECK_UTIL],[
   fi
 ])
 
+m4_define([AT_SCRIPT_PREREQ],[
+  echo "sth" > expected
+  script -q -c "echo sth" /dev/null | sed 's|\r||' > output
+  rm -rf output expected
+])
+
 m4_define([AT_XATTRS_UTILS_PREREQ],[
   file=$(TMPDIR=. mktemp fiXXXXXX)
   AT_CHECK_UTIL(setfattr -n user.test -v test $file,0)
@@ -213,6 +219,7 @@ m4_include([gzip.at])
 m4_include([recurse.at])
 m4_include([recurs02.at])
 m4_include([shortrec.at])
+m4_include([iotty.at])
 
 AT_BANNER([The --same-order option])
 m4_include([same-order01.at])
-- 
1.8.5.3