[gdb/testsuite] Rewrite valgrind-db-attach.exp to use vgdb

The valgrind option --db-attach has been deprecated in version 3.10.0, and
removed in version 3.11.0, so the valgrind-db-attach.exp testcase is
unsupported starting version 3.11.0.

Rewrite the test-case to use vgdb instead (making it supported starting
version 3.7.0).

Tested on x86_64-linux with and without --target_board=native-gdbserver.

2018-10-25  Tom de Vries  <tdevries@suse.de>

	* gdb.base/valgrind-db-attach.exp: Rewrite to use vgdb.

1 files changed, 55 insertions, 25 deletions

diff --git a/gdb/testsuite/gdb.base/valgrind-db-attach.exp b/gdb/testsuite/gdb.base/valgrind-db-attach.exp
index 3e40283a955..348f74379dd 100644
--- a/gdb/testsuite/gdb.base/valgrind-db-attach.exp
+++ b/gdb/testsuite/gdb.base/valgrind-db-attach.exp
@@ -23,16 +23,8 @@ if {[build_executable $testfile.exp $testfile $srcfile {debug}] == -1} {
     return -1
 }
 
-gdb_exit
-
-# remote_spawn breaks the command on each whitespace despite possible quoting.
-# Use backslash-escaped whitespace there instead:
-
-set db_command "--db-command=$GDB $INTERNAL_GDBFLAGS $GDBFLAGS [host_info gdb_opts] %f %p"
-regsub -all " " $db_command "\\ " db_command
-
 set test "spawn valgrind"
-set cmd "valgrind --db-attach=yes $db_command $binfile"
+set cmd "valgrind --vgdb-error=0 $binfile"
 set res [remote_spawn host $cmd]
 if { $res < 0 || $res == "" } {
     verbose -log "Spawning $cmd failed."
@@ -43,18 +35,13 @@ pass $test
 # Declare GDB now as running.
 set gdb_spawn_id $res
 
-# GDB spawned by `valgrind --db-attach=yes' stops already after the startup is
-# executed, like with non-extended gdbserver.  It is also not correct to
-# run/attach the inferior.
+# GDB started by vgdb stops already after the startup is executed, like with
+# non-extended gdbserver.  It is also not correct to run/attach the inferior.
 set use_gdb_stub 1
 
 set test "valgrind started"
 # The trailing '.' differs for different memcheck versions.
 gdb_test_multiple "" $test {
-    -re "valgrind: Unknown option: --db-attach=yes" {
-	unsupported $test
-	return -1
-    }
     -re "Memcheck, a memory error detector\\.?\r\n" {
 	pass $test
     }
@@ -72,23 +59,63 @@ gdb_test_multiple "" $test {
 	unsupported $test
 	return -1
     }
+    -re "valgrind: Bad option.*--vgdb-error=0" {
+	# valgrind is not >= 3.7.0.
+	unsupported $test
+	return -1
+    }
+}
+
+set test "vgdb prompt"
+# The trailing '.' differs for different memcheck versions.
+gdb_test_multiple "" $test {
+    -re "  (target remote | \[^\r\n\]*/vgdb \[^\r\n\]*)\r\n" {
+	set vgdbcmd $expect_out(1,string)
+	pass $test
+    }
 }
 
+# Do not kill valgrind.
+set valgrind_spawn_id [board_info host fileid]
+unset gdb_spawn_id
+set board [host_info name]
+unset_board_info fileid
+
+clean_restart $testfile
+
+# Make sure we're disconnected, in case we're testing with the
+# native-extended-gdbserver board, where gdb_start/gdb_load spawn
+# gdbserver and connect to it.
+gdb_test "disconnect" ".*"
+
+gdb_test "$vgdbcmd" " in \\.?_start .*" "target remote for vgdb"
+
+gdb_test "monitor v.set gdb_output" "valgrind output will go to gdb.*"
+
 set double_free [gdb_get_line_number "double-free"]
 
-set test "attach to debugger"
-gdb_test_multiple "" $test {
-    -re "Invalid free\\(\\).*: main \\(${srcfile}:$double_free\\)\r\n.*---- Attach to debugger \\? --- \[^\r\n\]* ---- " {
-	send_gdb "y\r"
+set test "continue"
+gdb_test_multiple "continue" $test {
+    -re "Invalid free\\(\\).*: main \\(${srcfile}:$double_free\\)\r\n.*$gdb_prompt $" {
+	pass $test
+    }
+    -re "Remote connection closed.*\r\n$gdb_prompt $" {
+	fail "$test (remote connection closed)"
+	# Only if valgrind got stuck.
+	kill_wait_spawned_process $valgrind_spawn_id
+	return -1
     }
-    -re "---- Attach to debugger \\? --- \[^\r\n\]* ---- " {
-	send_gdb "n\r"
-	exp_continue
+    -re "The program is not being run\\.\r\n$gdb_prompt $" {
+	fail "$test (valgrind vgdb has terminated)"
+	# Only if valgrind got stuck.
+	kill_wait_spawned_process $valgrind_spawn_id
+	return -1
+    }
+    -re "\r\n$gdb_prompt $" {
+	pass "$test (false warning)"
     }
 }
 
-gdb_test "" ".*" "eat first prompt"
-
 # Initialization from default_gdb_start.
 gdb_test_no_output "set height 0"
 gdb_test_no_output "set width 0"
@@ -97,3 +124,6 @@ gdb_test "bt" "in main \\(.*\\) at .*${srcfile}:$double_free"
 
 # Explicitly kill the program so it doesn't dump core when we quit->detach.
 gdb_test "kill" "" "kill program" "Kill the program being debugged.*y or n. $" "y"
+
+# Only if valgrind got stuck.
+kill_wait_spawned_process $valgrind_spawn_id