[PATCH] Set $trace_frame and $tracepoint on disconnect

[Yao Qi <yao at codesourcery dot com>]

Hi, 
the test case of this patch is to test the value of
$trace_frame and $tracepoint after GDB disconnects from remote.
Without applying the chunk for tracepoint.c, we'll get two fails,

  FAIL: gdb.trace/disconnected-tracing.exp: tfind: p $trace_frame
  FAIL: gdb.trace/disconnected-tracing.exp: tfind: p $tracepoint

which are about not setting $trace_frame and $tracepoint to -1.

The chunk for tracepoint.c is to set these variables correctly
when GDB disconnects and some small refactors in code.
Regression tested on x86_64-linux, two fails above are fixed.
OK to apply?

gdb:

2012-08-21  Yao Qi  <yao@codesourcery.com>

	* tracepoint.c (disconnect_tracing): Call set_tracepoint_num.
	(tfind_1): Don't call registers_changed, set_traceframe_num,
	and clear_traceframe_info.
	Call set_current_traceframe.
	(set_current_traceframe): call set_traceframe_num.

gdb/testsuite:

2012-08-21  Yao Qi  <yao@codesourcery.com>

	* gdb.trace/disconnected-tracing.c (start, end): New.
	(main): Call start and end.
	* gdb.trace/disconnected-tracing.exp (disconnected_tracing): Move
	existing tests into this proc.
	(disconnected_tfind): New.
---
 gdb/testsuite/gdb.trace/disconnected-tracing.c   |   10 ++
 gdb/testsuite/gdb.trace/disconnected-tracing.exp |  104 ++++++++++++++++------
 gdb/tracepoint.c                                 |    9 +-
 3 files changed, 93 insertions(+), 30 deletions(-)

diff --git a/gdb/testsuite/gdb.trace/disconnected-tracing.c b/gdb/testsuite/gdb.trace/disconnected-tracing.c
index 91d66ed..d4f54b2 100644
--- a/gdb/testsuite/gdb.trace/disconnected-tracing.c
+++ b/gdb/testsuite/gdb.trace/disconnected-tracing.c
@@ -15,7 +15,17 @@
    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
 
+void
+end (void)
+{}
+
+void
+start (void)
+{}
+
 int main ()
 {
+  start ();
+  end ();
   return 0;
 }
diff --git a/gdb/testsuite/gdb.trace/disconnected-tracing.exp b/gdb/testsuite/gdb.trace/disconnected-tracing.exp
index 79194f1..ed6bfd4 100644
--- a/gdb/testsuite/gdb.trace/disconnected-tracing.exp
+++ b/gdb/testsuite/gdb.trace/disconnected-tracing.exp
@@ -43,32 +43,84 @@ if ![gdb_target_supports_trace] {
     return -1;
 }
 
-delete_breakpoints
-gdb_test_no_output "set confirm off"
-gdb_test_no_output "set disconnected-tracing on"
-gdb_test "trace main" ".*"
-gdb_test_no_output "tstart"
-
-gdb_test "info tracepoints" ".*in main at.*" "first info tracepoints"
-
-gdb_test "disconnect" "Ending remote debugging\\." "first disconnect"
-if { [gdb_reconnect] == 0 } {
-    pass "first reconnect after unload"
-} else {
-    fail "first reconnect after unload"
-    return 0
-}
-gdb_test "info tracepoints" ".*in main at.*" "second info tracepoints"
+# Disconnect in tracing.
 
-delete_breakpoints
-gdb_test "info tracepoints" ".*No tracepoints..*" "third info tracepoints"
+proc disconnected_tracing {  } { with_test_prefix "trace" {
+    global executable
 
-gdb_test "disconnect" "Ending remote debugging\\." "second disconnect"
-if { [gdb_reconnect] == 0 } {
-    pass "second reconnect after unload"
-} else {
-    fail "second reconnect after unload"
-    return 0
-}
-gdb_test "info tracepoints" ".*in main at.*" "fourth info tracepoints"
+    # Start with a fresh gdb.
+    clean_restart ${executable}
+    if ![runto_main] {
+	fail "Can't run to main"
+	return -1
+    }
+
+    gdb_test_no_output "set confirm off"
+    gdb_test_no_output "set disconnected-tracing on"
+    gdb_test "trace main" ".*"
+    gdb_test_no_output "tstart"
+
+    gdb_test "info tracepoints" ".*in main at.*" "first info tracepoints"
+
+    gdb_test "disconnect" "Ending remote debugging\\." "first disconnect"
+    if { [gdb_reconnect] == 0 } {
+	pass "first reconnect after unload"
+    } else {
+	fail "first reconnect after unload"
+	return 0
+    }
+    gdb_test "info tracepoints" ".*in main at.*" "second info tracepoints"
+
+    delete_breakpoints
+    gdb_test "info tracepoints" ".*No tracepoints..*" "third info tracepoints"
+
+    gdb_test "disconnect" "Ending remote debugging\\." "second disconnect"
+    if { [gdb_reconnect] == 0 } {
+	pass "second reconnect after unload"
+    } else {
+	fail "second reconnect after unload"
+	return 0
+    }
+    gdb_test "info tracepoints" ".*in main at.*" "fourth info tracepoints"
+}}
+
+disconnected_tracing
+
+# Disconnected in tfind
+
+proc disconnected_tfind {  } { with_test_prefix "tfind" {
+    global executable
+    global decimal
+
+    # Start with a fresh gdb.
+    clean_restart ${executable}
+    if ![runto_main] {
+	fail "Can't run to main"
+	return -1
+    }
+
+    gdb_test_no_output "set confirm off"
+    gdb_test_no_output "set disconnected-tracing on"
+    gdb_test "trace start" ".*"
+    gdb_test_no_output "tstart"
+
+    gdb_test "break end" "Breakpoint ${decimal} at .*"
+    gdb_test "continue" "Continuing\\.\[ \r\n\]+Breakpoint.*"
+    gdb_test_no_output "tstop"
+
+    gdb_test "tfind" "Found trace frame 0, tracepoint .*" "tfind frame 0"
+    gdb_test "p \$trace_frame" ".*\\\$${decimal} = 0.*" \
+	"p \$trace_frame before disconnected"
+    gdb_test "p \$tracepoint" ".*\\\$${decimal} = 2.*" \
+	"p \$tracepoint before disconnected"
+
+    gdb_test "disconnect" "Ending remote debugging\\." "first disconnect"
+
+    gdb_test "p \$trace_frame" ".*\\\$${decimal} = -1.*"
+    gdb_test "p \$tracepoint" ".*\\\$${decimal} = -1.*"
+    gdb_test "p \$trace_line" ".*\\\$${decimal} = -1.*"
+    gdb_test "p \$trace_file" ".*\\\$${decimal} = void.*"
+    gdb_test "p \$trace_func" ".*\\\$${decimal} = void.*"
+}}
 
+disconnected_tfind
diff --git a/gdb/tracepoint.c b/gdb/tracepoint.c
index a59f7b7..3bdd129 100644
--- a/gdb/tracepoint.c
+++ b/gdb/tracepoint.c
@@ -2212,6 +2212,7 @@ disconnect_tracing (int from_tty)
      full tfind_1 behavior because we're in the middle of detaching,
      and there's no point to updating current stack frame etc.  */
   set_current_traceframe (-1);
+  set_tracepoint_num (-1);
   set_traceframe_context (NULL);
 }
 
@@ -2285,10 +2286,10 @@ tfind_1 (enum trace_find_type type, int num,
   tp = get_tracepoint_by_number_on_target (target_tracept);
 
   reinit_frame_cache ();
-  registers_changed ();
   target_dcache_invalidate ();
-  set_traceframe_num (target_frameno);
-  clear_traceframe_info ();
+
+  set_current_traceframe (target_frameno);
+
   set_tracepoint_num (tp ? tp->base.number : target_tracept);
   if (target_frameno == -1)
     set_traceframe_context (NULL);
@@ -3273,7 +3274,7 @@ set_current_traceframe (int num)
   if (newnum != num)
     warning (_("could not change traceframe"));
 
-  traceframe_number = newnum;
+  set_traceframe_num (newnum);
 
   /* Changing the traceframe changes our view of registers and of the
      frame chain.  */
-- 
1.7.7.6