[PATCH 1/2] Tests on displaying trace data in MI

[Yao Qi <yao at codesourcery dot com>]

GDB has some MI commands (such as -stack-list-locals) to examine the
local variables and arguments on a certain frame.  These commands also
work when examining trace frames.  However, we don't have a test case
to these commands on the case that reading from trace frames.  This
patch adds a test case, and it is a preparatory patch for my
following patches.

When I write this test case, I get some fails:

 FAIL: gdb.trace/mi-trace-unavailable.exp: ctf: -stack-list-arguments 2
 FAIL: gdb.trace/mi-trace-unavailable.exp: ctf: -stack-list-variables 2
 FAIL: gdb.trace/mi-trace-unavailable.exp: tfile: -stack-list-arguments 2
 FAIL: gdb.trace/mi-trace-unavailable.exp: tfile: -stack-list-variables 2

The problem can be reproduced in the follow steps,

  1. connect to the remote target, insert tracepoint, start the tracing,
resume the inferior, and stop tracing when it stops,
  2. save trace data to tfile,
  3. switch to tfind mode to examine some local variables and arguments,
  4. change to tfile target, and do the same as step 3 does.  Some
variables are unavailable, which is wrong.

Ideally, command 'tfind none' (to return from tfind mode) is needed
between step 3 and 4.  The 'right' fix would be add '-trace-find none'
command in the test, but it is hard to prevent users doing this, IMO.
I decide to make GDB more robust when users do something incorrect.
That is what the next patch does.

gdb/testsuite/

	gdb.trace/mi-trace-unavailable.exp: New.
	gdb.trace/trace-unavailable.c: New.
---
 gdb/testsuite/gdb.trace/mi-trace-unavailable.exp |  143 ++++++++++++++++++++++
 gdb/testsuite/gdb.trace/trace-unavailable.c      |   40 ++++++
 2 files changed, 183 insertions(+), 0 deletions(-)
 create mode 100644 gdb/testsuite/gdb.trace/mi-trace-unavailable.exp
 create mode 100644 gdb/testsuite/gdb.trace/trace-unavailable.c

diff --git a/gdb/testsuite/gdb.trace/mi-trace-unavailable.exp b/gdb/testsuite/gdb.trace/mi-trace-unavailable.exp
new file mode 100644
index 0000000..263aaae
--- /dev/null
+++ b/gdb/testsuite/gdb.trace/mi-trace-unavailable.exp
@@ -0,0 +1,143 @@
+# Copyright 2013 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/>.
+
+load_lib trace-support.exp
+
+standard_testfile trace-unavailable.c
+
+set executable $testfile
+
+if  { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${binfile}" \
+	   executable {debug nowarnings}] != "" } {
+     untested ${testfile}.exp
+     return -1
+}
+# Test target supports tracepoints or not.
+
+clean_restart $executable
+
+if ![runto_main] {
+    fail "Can't run to main to check for trace support"
+    return -1
+}
+
+if ![gdb_target_supports_trace] {
+    unsupported "Current target does not support trace"
+    return -1
+}
+
+gdb_exit
+
+load_lib mi-support.exp
+set MIFLAGS "-i=mi"
+
+if [mi_gdb_start] {
+    return
+}
+mi_run_to_main
+
+mi_gdb_test "-break-insert marker" \
+    "\\^done,bkpt=\{number=\"${decimal}\",type=\"breakpoint\".*\"\}" \
+    "insert tracepoint on marker"
+mi_gdb_test "-break-insert -a bar" \
+    "\\^done,bkpt=\{number=\"${decimal}\",type=\"tracepoint\".*\"\}" \
+    "insert tracepoint on bar"
+
+# Define an action.
+send_gdb "actions\n"
+gdb_expect {
+    -re "End with" {
+    }
+}
+send_gdb "collect array\ncollect j\nend\n"
+set test "define actions"
+gdb_expect {
+    -re ".*${mi_gdb_prompt}$" {
+	pass $test
+    }
+    timeout {
+	fail "$test (timeout)"
+    }
+}
+
+mi_gdb_test "-trace-start" {.*\^done} "trace start"
+mi_send_resuming_command "exec-continue" "continuing to marker"
+mi_gdb_test "-trace-stop" {.*} "trace stop"
+
+# Save trace frames to tfile.
+set tracefile [standard_output_file ${testfile}]
+mi_gdb_test "-trace-save ${tracefile}.tf" ".*\\^done" \
+    "save tfile trace file"
+# Save trace frames to ctf.
+mi_gdb_test "-trace-save -ctf ${tracefile}.ctf" ".*\\^done" \
+    "save ctf trace file"
+
+mi_gdb_test "-gdb-set print entry-values no" {\^done} \
+    "-gdb-set print entry-values no"
+
+# Test MI commands '-stack-list-locals', '-stack-list-arguments', and
+# '-stack-list-variables'.
+
+proc test_stack_list_commands { data_source } {
+    global decimal
+
+    with_test_prefix "$data_source" {
+	mi_gdb_test "-trace-find frame-number 0" \
+	    ".*\\^done,found=\"1\",tracepoint=\"${decimal}\",traceframe=\"0\",frame=\{.*" \
+	    "-trace-find frame-number 0"
+
+	# Test MI command '-stack-list-locals'.
+	mi_gdb_test "-stack-list-locals 2" \
+	    ".*\\^done,locals=\\\[\{name=\"array\",type=\"unsigned char \\\[2\\\]\"\},\{name=\"i\",type=\"int\",value=\"<unavailable>\"\}\\\]" \
+	    "-stack-list-locals 2"
+
+	# Test MI command '-stack-list-arguments'.
+	mi_gdb_test "-stack-list-arguments 2" \
+	    ".*\\^done,stack-args=\\\[frame=\{level=\"0\",args=\\\[\{name=\"j\",type=\"int\",value=\"4\"\},\{name=\"s\",type=\"char \\\*\",value=\"<unavailable>\"\}\\\]\},.*\}.*" \
+	    "-stack-list-arguments 2"
+
+	# Test MI command '-stack-list-variables'.
+	mi_gdb_test "-stack-list-variables 2" \
+	    ".*\\^done,variables=\\\[\{name=\"j\",arg=\"1\",type=\"int\",value=\"4\"\},\{name=\"s\",arg=\"1\",type=\"char \\\*\",value=\"<unavailable>\"\},\{name=\"array\",type=\"unsigned char \\\[2\\\]\"\},\{name=\"i\",type=\"int\",value=\"<unavailable>\"\}\\\]" \
+	    "-stack-list-variables 2"
+
+	# Don't issue command '-trace-find none' to return from the
+	# tfind mode (examining trace frames) on purpose, in order
+	# to test GDB is able to clear its local state on tracing
+	# in the following steps.
+	# mi_gdb_test "-trace-find none" ".*\\^done,found=\"0\".*" "-trace-find none"
+    }
+}
+
+test_stack_list_commands "live"
+
+# Change target to ctf if GDB supports
+send_gdb "-target-select ctf ${tracefile}.ctf\n"
+gdb_expect {
+    -re ".*\\^connected.*${mi_gdb_prompt}$" {
+	# GDB supports ctf, do the test.
+	test_stack_list_commands "ctf"
+    }
+    -re ".*\\^error,msg=\"Undefined target command.*${mi_gdb_prompt}$" {
+	# GDB doesn't support ctf, skip the test.
+    }
+}
+
+# Change target to tfile.
+mi_gdb_test "-target-select tfile ${tracefile}.tf" ".*\\^connected.*" \
+    "-target-select tfile"
+test_stack_list_commands "tfile"
+
+mi_gdb_exit
diff --git a/gdb/testsuite/gdb.trace/trace-unavailable.c b/gdb/testsuite/gdb.trace/trace-unavailable.c
new file mode 100644
index 0000000..9b3e230
--- /dev/null
+++ b/gdb/testsuite/gdb.trace/trace-unavailable.c
@@ -0,0 +1,40 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2013 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/>.  */
+
+static void
+bar (int j, char *s)
+{
+  unsigned char array[2];
+  int i = 0;
+
+  array[0] = 'c';
+  array[1] = 'd';
+}
+
+static void
+marker (void)
+{}
+
+int
+main (void)
+{
+  char s[4];
+
+  bar (4, s);
+  marker ();
+  return 0;
+}
-- 
1.7.7.6