[8/9] testsuite: Add script to quickly re-run tests

diff --git a/gdb/testsuite/README b/gdb/testsuite/README
index 98fc8d1b852..b5fbb456bee 100644
--- a/gdb/testsuite/README
+++ b/gdb/testsuite/README
@@ -95,6 +95,29 @@  example:
 
 The script will output its analysis report to the standard output.
 
+Re-running Tests Outside The Testsuite
+**************************************
+
+When running a test, the arguments used to run GDB are saved to gdb.cmd
+and any commands sent to GDB are saved to gdb.in.  As well as being a
+reference of the commands run, they can be used to manually re-run a test
+by giving the .in file as a batch file to a GDB launched with the arguments
+in the .cmd file.  For many tests you can use just the .in file:
+	$ gdb -x gdb.in
+
+Tests that run GDB multiple times will append .1, .2, .3 etc to the end
+of each .cmd and .in file.
+
+For tests requiring gdbserver, this can by executing the contents of
+gdbserver.cmd.  Alternatively, the gdbserver.replay file (created when
+running the test with GDBSERVER_DEBUG="replay") can be used with the
+gdbreplay test.
+
+This process can be automated with the "replaytest" script.
+For example:
+	$ replaytest gdb testsuite/outputs/gdb.base/store
+For more details see the documentation in the script.
+
 Running the Performance Tests
 *****************************
 
diff --git a/gdb/testsuite/lib/gdbserver-support.exp b/gdb/testsuite/lib/gdbserver-support.exp
index 2ccc717ef60..ade99c0ea16 100644
--- a/gdb/testsuite/lib/gdbserver-support.exp
+++ b/gdb/testsuite/lib/gdbserver-support.exp
@@ -484,7 +484,7 @@  proc gdbserver_run { child_args } {
     # Kill anything running before we try to start gdbserver, in case
     # we are sharing a serial connection.
     global gdb_prompt
-    send_gdb "kill\n"
+    send_gdb "kill\n" optional
     gdb_expect 120 {
 	-re "Kill the program being debugged. .y or n. $" {
 	    send_gdb "y\n"
diff --git a/gdb/testsuite/replaytest b/gdb/testsuite/replaytest
new file mode 100755
index 00000000000..4c11d9735f3
--- /dev/null
+++ b/gdb/testsuite/replaytest
@@ -0,0 +1,147 @@ 
+#!/bin/bash
+
+# Copyright (C) 2019 Free Software Foundation, Inc.
+#
+# This file is part of GDB.
+#
+# 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/>.
+
+#
+# This script uses GDB to replay previously run tests using the .in and
+# .cmd files from the output directory of a test.
+#
+# For example:
+#    $ replaytest gdb testsuite/outputs/gdb.base/store
+#
+#
+# For tests that have been runing using gdbserver (for example with
+# board file native-gdbserver), the test script should be run in two
+# terminals, using gdbserver and gdb modes.
+#
+# For example, in two different terminals:
+#    $ replaytest -b gdbserver testsuite/outputs/gdb.base/store
+#    $ replaytest -b gdb testsuite/outputs/gdb.base/store
+#
+# Alternatively, instead of running gdbserver, the gdbreplay tool can
+# be used instead. This uses the .replay file which is created when the
+# test is run with GDBSERVER_DEBUG="replay". gdbreplay must be in your
+# $PATH.
+#
+#
+# Tests that run GDB (and gdbserver) multiple times will create .1, .2
+# .3 etc files for each instance of GDB.  You can run a specified
+# instance using the -i flag
+#
+# For example:
+#    $ replaytest -b -i 23 gdb testsuite/outputs/gdb.base/infcall-nested-structs
+#
+# Note that to successfully run to the end of the test, the .in file must be
+# free from the answers to any interactive gdb prompts (for example the y from
+# a y/n question) or any command that causes gdb to report an error.
+#
+#
+# Usage: replaytest [-b] [-i instance] [-e] {gdb|gdbserver|replay} test_output_dir
+#
+#    -b : Run GDB in batch mode (ie: exit GDB at the end of the test).
+#    -i : Run the given instance of the test. Defaults to 0.
+#    -e : Don't run the test, just echo the command line instead.
+#
+#    test_output_dir : Directory containing all the test output files.
+#
+
+usage()
+{
+  echo "$0 [-b] [-i instance] [-e] {gdb|gdbserver|replay} test_output_dir"
+  exit 2
+}
+
+# Check file $1 exists, using test operator $2 (defaults to -e).
+check_exists()
+{
+  if [ ! ${2:-"-e"} "${1}" ]; then echo Error: Cannot find $1; exit 2; fi
+}
+
+# Run the given command in $1...n
+execute()
+{
+  if [ -n "$ECHO" ]
+  then
+    echo $@
+  else
+    # Pipe the command we want to run to a file then execute the file.  This
+    # ensures spaces within quoatation marks args get interpreted correctly.
+    OUTFILE=$(mktemp)
+    echo $@ > ${OUTFILE}
+    bash ${OUTFILE}
+    rm ${OUTFILE}
+  fi
+}
+
+# Parse command line
+while getopts bi:e line
+do
+  case $line in
+  b) EXTRA_GDBCMD="${EXTRA_GDBCMD} --batch";;
+  i) INSTANCE=".$OPTARG";;
+  e) ECHO=1;;
+  *) usage;;
+  esac
+done
+shift $(($OPTIND - 1))
+if [[ $# -ne 2 ]]; then usage; fi;
+MODE=$1
+TESTDIR=$2
+check_exists ${TESTDIR} -d
+
+
+case $MODE in
+
+"gdb") 
+  # Run the .in file through GDB by appending it to the end of the .cmd contents.
+  CMDFILE=${TESTDIR}/gdb.cmd${INSTANCE}
+  INFILE=${TESTDIR}/gdb.in${INSTANCE}
+  check_exists ${CMDFILE}
+  check_exists ${INFILE}
+  execute "$(cat $CMDFILE) ${EXTRA_GDBCMD} -x ${INFILE}"
+  ;;
+
+"gdbserver") 
+  # Run gdbserver using the .cmd file.
+  GDBSERVER_CMDFILE=${TESTDIR}/gdbserver.cmd${INSTANCE}
+  check_exists ${GDBSERVER_CMDFILE}
+  execute $(cat $GDBSERVER_CMDFILE)
+  ;;
+
+"replay") 
+  GDBSERVER_REPLAYFILE=${TESTDIR}/gdbserver.replay${INSTANCE}
+  check_exists ${GDBSERVER_REPLAYFILE}
+
+  # Extract the connection from the .cmd file.
+  GDBSERVER_CMDFILE=${TESTDIR}/gdbserver.cmd${INSTANCE}
+  check_exists ${GDBSERVER_CMDFILE}
+  GDBSERVER_HOST=$(grep -o '[^ ]*:[^ ]*' ${GDBSERVER_CMDFILE})
+
+  # Run the .replay file through gdbreplay.
+  execute gdbreplay ${GDBSERVER_REPLAYFILE} ${GDBSERVER_HOST}
+  ;;
+
+*)
+  echo "Unknown mode $MODE"
+  usage
+  ;;
+
+esac
+
+
+