Fix PR 20345 - call_function_by_hand_dummy: Assertion `tp->thread_fsm == &sm->thread_fsm' failed

If you run an infcall from the command line, and immediately after run
some other command, GDB incorrectly processes the other command before
the infcall finishes.

The problem is that the fix for PR gdb/20418 (Problems with
synchronous commands and new-ui, git 3eb7562a98) moved the
add_file_handler/delete_file_handler calls out of
target_terminal_$foo, and missed adjusting the infcall code.

gdb/ChangeLog:
2016-09-28  Pedro Alves  <palves@redhat.com>

	* infcall.c (run_inferior_call): Remove input from the event
	loop while running the infcall.

gdb/testsuite/ChangeLog:
2016-09-28  Pedro Alves  <palves@redhat.com>

	* gdb.base/infcall-input.c: New file.
	* gdb.base/infcall-input.exp: New file.

gdb/ChangeLog

@@ -1,3 +1,8 @@
+2016-09-28  Pedro Alves  <palves@redhat.com>
+
+	* infcall.c (run_inferior_call): Remove input from the event
+	loop while running the infcall.
+
 2016-09-27  Fredrik Hederstierna  <fredrik.hederstierna@verisure.com>
 
 	* arm-tdep.c (arm_m_addr_is_magic): New function.

gdb/infcall.c

@@ -584,6 +584,8 @@ run_inferior_call (struct call_thread_fsm *sm,
      fetch_inferior_event.  */
   current_ui->async = 0;
 
+  delete_file_handler (current_ui->input_fd);
+
   call_thread->control.in_infcall = 1;
 
   clear_proceed_status (0);
@@ -617,6 +619,10 @@ run_inferior_call (struct call_thread_fsm *sm,
      state again here.  In other cases, stdin will be re-enabled by
      inferior_event_handler, when an exception is thrown.  */
   current_ui->prompt_state = saved_prompt_state;
+  if (current_ui->prompt_state == PROMPT_BLOCKED)
+    delete_file_handler (current_ui->input_fd);
+  else
+    ui_register_input_event_handler (current_ui);
   current_ui->async = saved_ui_async;
 
   /* At this point the current thread may have changed.  Refresh

gdb/testsuite/ChangeLog

@@ -1,3 +1,8 @@
+2016-09-28  Pedro Alves  <palves@redhat.com>
+
+	* gdb.base/infcall-input.c: New file.
+	* gdb.base/infcall-input.exp: New file.
+
 2016-09-22  Yao Qi  <yao.qi@linaro.org>
 
 	* lib/gdbserver-support.exp: Rename mi_gdb_exit.

gdb/testsuite/gdb.base/infcall-input.c

@@ -0,0 +1,34 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2016 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/>.  */
+
+#include <unistd.h>
+
+int
+some_function (void)
+{
+  /* Sleep a bit to make sure the next command is queued before this
+     function returns.  */
+  sleep (1);
+  return 1;
+}
+
+int
+main (int argc, char **argv)
+{
+  some_function ();
+  return 0;
+}

gdb/testsuite/gdb.base/infcall-input.exp

@@ -0,0 +1,55 @@
+# Copyright 2016 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/>.
+
+# Test that gdb does not process input while a (synchronous) infcall
+# is in progress.
+
+standard_testfile
+
+if [target_info exists gdb,cannot_call_functions] {
+    unsupported "can not call functions"
+    continue
+}
+
+if {[prepare_for_testing $testfile.exp $testfile $srcfile debug]} {
+    untested "compile failed"
+    return -1
+}
+
+if ![runto_main] then {
+    fail "Couldn't run to main"
+    return -1
+}
+
+# Run an infcall that takes a little bit to complete.
+send_gdb "print some_function()\n"
+
+# Send another command while the infcall is ongoing.  It must only be
+# processed after the infcall finishes.
+send_gdb "next\n"
+
+set test "print some_function()"
+gdb_test_multiple "" $test {
+    -re " = 1\r\n$gdb_prompt " {
+	pass $test
+    }
+}
+
+set test "next"
+gdb_test_multiple "" $test {
+    -re "return 0;\r\n$gdb_prompt " {
+	pass $test
+    }
+}