Re: [patch] Fix `shell' command for async (PR 12850)

[Jan Kratochvil <jan dot kratochvil at redhat dot com>]

On Tue, 07 Jun 2011 19:13:24 +0200, Pedro Alves wrote:
> > -    while ((rc = wait (&status)) != pid && rc != -1)
> > +    while ((rc = waitpid (pid, &status, 0)) != pid && rc != -1)
> >        ;
> 
> Pedantically, I think this could be simplified.  PID is
> a specific pid, not -1, and when WNOHANG is not used,
> waitpid(pid, ..., 0) can only return pid or -1.
> Thus, the loop only ever executes once.

Oops, yes, changed.

Checked in.


Thanks,
Jan


http://sourceware.org/ml/gdb-cvs/2011-06/msg00039.html

--- src/gdb/ChangeLog	2011/06/07 12:31:03	1.13083
+++ src/gdb/ChangeLog	2011/06/07 17:26:41	1.13084
@@ -1,3 +1,9 @@
+2011-06-07  Jan Kratochvil  <jan.kratochvil@redhat.com>
+	    Pedro Alves  <pedro@codesourcery.com>
+
+	* cli/cli-cmds.c (shell_escape): Use waitpid.
+	* rs6000-nat.c (exec_one_dummy_insn): Likewise.
+
 2011-06-07  Tristan Gingold  <gingold@adacore.com>
 
 	* xcoffread.c (dwarf2_xcoff_names): New variable.
--- src/gdb/testsuite/ChangeLog	2011/06/06 13:33:07	1.2739
+++ src/gdb/testsuite/ChangeLog	2011/06/07 17:26:46	1.2740
@@ -1,3 +1,8 @@
+2011-06-07  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+	* gdb.base/async-shell.c: New file.
+	* gdb.base/async-shell.exp: New file.
+
 2011-06-06  Pedro Alves  <pedro@codesourcery.com>
 
 	* gdb.threads/pending-step.exp: Add more context to SIGTRAP match.
--- src/gdb/rs6000-nat.c	2011/01/11 15:10:01	1.104
+++ src/gdb/rs6000-nat.c	2011/06/07 17:26:45	1.105
@@ -614,7 +614,7 @@
 
   do
     {
-      pid = wait (&status);
+      pid = waitpid (PIDGET (inferior_ptid), &status, 0);
     }
   while (pid != PIDGET (inferior_ptid));
 
--- src/gdb/cli/cli-cmds.c	2011/04/04 17:41:07	1.113
+++ src/gdb/cli/cli-cmds.c	2011/06/07 17:26:46	1.114
@@ -726,7 +726,7 @@
   chdir (current_directory);
 #endif
 #else /* Can fork.  */
-  int rc, status, pid;
+  int status, pid;
 
   if ((pid = vfork ()) == 0)
     {
@@ -750,8 +750,7 @@
     }
 
   if (pid != -1)
-    while ((rc = wait (&status)) != pid && rc != -1)
-      ;
+    waitpid (pid, &status, 0);
   else
     error (_("Fork failed"));
 #endif /* Can fork.  */
--- src/gdb/testsuite/gdb.base/async-shell.c
+++ src/gdb/testsuite/gdb.base/async-shell.c	2011-06-07 17:27:07.593604000 +0000
@@ -0,0 +1,22 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2011 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/>.  */
+
+int
+main (void)
+{
+  return sleep (600);
+}
--- src/gdb/testsuite/gdb.base/async-shell.exp
+++ src/gdb/testsuite/gdb.base/async-shell.exp	2011-06-07 17:27:07.926556000 +0000
@@ -0,0 +1,42 @@
+# Copyright (C) 2011 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/>.
+
+set testfile async-shell
+if { [prepare_for_testing ${testfile}.exp ${testfile}] } {
+    return -1
+}
+
+gdb_test_no_output "set target-async on "
+gdb_test_no_output "set non-stop on"
+gdb_test "run &" "Starting program: \[^\r\n\]*"
+
+# `sleep 5' here would workaround the bug, do not sleep here.
+# "shell" could eat waitpid event from the asynchronous inferior process.
+
+gdb_test "shell echo foo" "foo"
+
+set test "interrupt"
+gdb_test_multiple $test $test {
+    -re "interrupt\r\n$gdb_prompt " {
+	pass $test
+    }
+}
+
+set test "process stopped"
+gdb_test_multiple "" $test {
+    -re "\r\n\\\[process \[0-9\]+\\\] #1 stopped\\\.\r\n" {
+	pass $test
+    }
+}