[PATCH] Indicate batch mode failures by exiting with nonzero status

[Gary Benson <gbenson@redhat.com>]

Hi all,

This patch causes GDB in batch mode to exit with nonzero status
if the last command to be executed fails.

Built and regtested on RHEL 7.5 x86_64.

Ok to commit?

Thanks,
Gary

--
gdb/ChangeLog:

	PR gdb/13000:
	* gdb/main.c (last_command_failed): New static global.
	(handle_command_errors): Set the above on error.
	(catch_command_errors): Clear the above before commands.
	(captured_main_1): Exit with nonzero status in batch mode
	if the last command to be executed failed.
	* NEWS: Mention the above.

gdb/testsuite/ChangeLog:

	PR gdb/13000:
	* gdb.base/batch-exit-status.exp: New file.
	* gdb.base/batch-exit-status.good-commands: Likewise.
	* gdb.base/batch-exit-status.bad-commands: Likewise.
---
 gdb/ChangeLog                                      | 10 ++++
 gdb/NEWS                                           |  3 ++
 gdb/main.c                                         | 13 ++++-
 gdb/testsuite/ChangeLog                            |  7 +++
 .../gdb.base/batch-exit-status.bad-commands        |  1 +
 gdb/testsuite/gdb.base/batch-exit-status.exp       | 63 ++++++++++++++++++++++
 .../gdb.base/batch-exit-status.good-commands       |  1 +
 7 files changed, 97 insertions(+), 1 deletion(-)
 create mode 100644 gdb/testsuite/gdb.base/batch-exit-status.bad-commands
 create mode 100644 gdb/testsuite/gdb.base/batch-exit-status.exp
 create mode 100644 gdb/testsuite/gdb.base/batch-exit-status.good-commands

diff --git a/gdb/NEWS b/gdb/NEWS
index 16d3d72..6af712a 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -10,6 +10,9 @@
 * DWARF index cache: GDB can now automatically save indices of DWARF
   symbols on disk to speed up further loading of the same binaries.
 
+* GDB in batch mode now exits with status 1 if the last command to be
+  executed failed.
+
 * New commands
 
 frame apply [all | COUNT | -COUNT | level LEVEL...] [FLAG]... COMMAND
diff --git a/gdb/main.c b/gdb/main.c
index e925128..31a6ee0 100644
--- a/gdb/main.c
+++ b/gdb/main.c
@@ -343,6 +343,10 @@ captured_command_loop ()
   quit_command (NULL, ui->instream == ui->stdin_stream);
 }
 
+/* Did the last invocation of catch_command_errors throw an error?  */
+
+static bool last_command_failed = false;
+
 /* Handle command errors thrown from within catch_command_errors.  */
 
 static int
@@ -350,6 +354,8 @@ handle_command_errors (struct gdb_exception e)
 {
   if (e.reason < 0)
     {
+      last_command_failed = true;
+
       exception_print (gdb_stderr, e);
 
       /* If any exception escaped to here, we better enable stdin.
@@ -372,6 +378,8 @@ static int
 catch_command_errors (catch_command_errors_const_ftype command,
 		      const char *arg, int from_tty)
 {
+  last_command_failed = false;
+
   TRY
     {
       int was_sync = current_ui->prompt_state == PROMPT_BLOCKED;
@@ -1134,8 +1142,11 @@ captured_main_1 (struct captured_main_args *context)
 
   if (batch_flag)
     {
+      int error_status = EXIT_FAILURE;
+      int *exit_arg = last_command_failed ? &error_status : NULL;
+
       /* We have hit the end of the batch file.  */
-      quit_force (NULL, 0);
+      quit_force (exit_arg, 0);
     }
 }
 
diff --git a/gdb/testsuite/gdb.base/batch-exit-status.bad-commands b/gdb/testsuite/gdb.base/batch-exit-status.bad-commands
new file mode 100644
index 0000000..4793acb
--- /dev/null
+++ b/gdb/testsuite/gdb.base/batch-exit-status.bad-commands
@@ -0,0 +1 @@
+bork
diff --git a/gdb/testsuite/gdb.base/batch-exit-status.exp b/gdb/testsuite/gdb.base/batch-exit-status.exp
new file mode 100644
index 0000000..bee4d72
--- /dev/null
+++ b/gdb/testsuite/gdb.base/batch-exit-status.exp
@@ -0,0 +1,63 @@
+# Copyright (C) 2018 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/>.
+
+# Check that "gdb -batch" exits with appropriate status.
+
+standard_testfile
+
+set good_commands "$srcdir/$subdir/batch-exit-status.good-commands"
+set bad_commands "$srcdir/$subdir/batch-exit-status.bad-commands"
+
+proc _test_exit_status {expect_status cmdline_opts} {
+    global gdb_spawn_id
+
+    gdb_exit
+    if {[gdb_spawn_with_cmdline_opts $cmdline_opts] != 0} {
+	fail "spawn"
+	return
+    }
+
+    set result [wait -i $gdb_spawn_id]
+    verbose $result
+    gdb_assert { [lindex $result 2] == 0 }
+    set actual_status [lindex $result 3]
+    gdb_assert { $actual_status == $expect_status }
+}
+
+proc test_exit_status {expect_status cmdline_opts} {
+    with_test_prefix $cmdline_opts {
+	_test_exit_status $expect_status $cmdline_opts
+    }
+}
+
+# gdb -batch with nothing to do should exit 0.
+test_exit_status 0 "-batch"
+
+# Bad command-line options should cause exit 1.
+test_exit_status 1 "-batch -jslkflsdjlkfjlksdjf"
+
+# gdb -batch with good commands should exit 0.
+test_exit_status 0 "-batch -ex \"info source\""
+test_exit_status 0 "-batch -x $good_commands"
+
+# gdb -batch with bad commands should exit 1.
+test_exit_status 1 "-batch -ex \"set not-a-thing 4\""
+test_exit_status 1 "-batch -x $bad_commands"
+
+# Success or failure of the last thing determines the exit code.
+test_exit_status 0 "-batch -ex \"set not-a-thing 4\" -x $good_commands"
+test_exit_status 0 "-batch -x $bad_commands -ex \"info source\""
+test_exit_status 1 "-batch -x $good_commands -x $bad_commands"
+test_exit_status 1 "-batch -x $good_commands -ex \"set not-a-thing 4\""
diff --git a/gdb/testsuite/gdb.base/batch-exit-status.good-commands b/gdb/testsuite/gdb.base/batch-exit-status.good-commands
new file mode 100644
index 0000000..80708a9
--- /dev/null
+++ b/gdb/testsuite/gdb.base/batch-exit-status.good-commands
@@ -0,0 +1 @@
+info mem
-- 
1.8.3.1