[PATCH] Notify observer of breakpoint auto-disabling

Patrick Monnerat via Gdb-patches
2021-08-15T00:34:15Z

As breakpoint_modified observer is currently notified upon breakpoint stop
before handling auto-disabling when enable count is reached, the observer is
never notified of the disabling.

The problem affects:
- The MI interpreter enabled= value when reporting =breakpoint-modified
- A Python event handler for breakpoint_modified using the "enabled"
member of its parameter
- insight: breakpoint GUI window is not properly updated upon auto-disable

This patch moves the observer notification after the auto-disabling
code and implements corresponding tests for the MI and Python cases.

Fixes https://sourceware.org/bugzilla/show_bug.cgi?id=23336
---
gdb/breakpoint.c | 2 +-
.../gdb.mi/mi-breakpoint-changed.exp | 41 +++++++++++++++++++
gdb/testsuite/gdb.python/py-breakpoint.exp | 21 ++++++++++
3 files changed, 63 insertions(+), 1 deletion(-)

diff --git a/gdb/breakpoint.c b/gdb/breakpoint.c
index 89af44ee4c6..feca224ccf4 100644
--- a/gdb/breakpoint.c
+++ b/gdb/breakpoint.c
@@ -5491,7 +5491,6 @@ bpstat_stop_status (const address_space *aspace,
if (bs->stop)
{
++(b->hit_count);
- gdb::observers::breakpoint_modified.notify (b);

/* We will stop here. */
if (b->disposition == disp_disable)
@@ -5501,6 +5500,7 @@ bpstat_stop_status (const address_space *aspace,
b->enable_state = bp_disabled;
removed_any = 1;
}
+ gdb::observers::breakpoint_modified.notify (b);
if (b->silent)
bs->print = 0;
bs->commands = b->commands;
diff --git a/gdb/testsuite/gdb.mi/mi-breakpoint-changed.exp b/gdb/testsuite/gdb.mi/mi-breakpoint-changed.exp
index 3f7ef8a79b6..0b814443b06 100644
--- a/gdb/testsuite/gdb.mi/mi-breakpoint-changed.exp
+++ b/gdb/testsuite/gdb.mi/mi-breakpoint-changed.exp
@@ -257,3 +257,44 @@ proc test_pending_resolved { } {
with_test_prefix "test_pending_resolved" {
test_pending_resolved
}
+
+# Test auto-disable is effective when notifying breakpoint-modified.
+
+proc test_auto_disable { } {
+ global mi_gdb_prompt
+ global lib_sl1 lib_sl2
+ global binfile
+
+ mi_clean_restart $binfile
+
+ mi_load_shlibs $lib_sl1 $lib_sl2
+
+ mi_runto_main
+
+ # Set the breakpoint.
+ mi_gdb_test "-break-insert -f pendfunc1" \
+ {(&.*)*.*~"Breakpoint 2 at.*\\n".*=breakpoint-created,bkpt=\{number="2",type="breakpoint".*\}.*\n\^done}
+
+ # Enable for one shot only.
+ mi_gdb_test "-break-enable count 1 2" \
+ {=breakpoint-modified,bkpt=\{number="2",type="breakpoint",disp="dis",enabled="y".*\}.*\n\^done}
+
+ mi_send_resuming_command "exec-continue" "continuing execution to breakpoint"
+
+ set test "breakpoint auto-disabling after enable count reached"
+ gdb_expect {
+ -re ".*=breakpoint-modified,bkpt=\{number=\"2\".*enabled=\"n\"" {
+ pass $test
+ }
+ -re ".*${mi_gdb_prompt}$" {
+ fail $test
+ }
+ timeout {
+ fail "$test (timeout)"
+ }
+ }
+}
+
+with_test_prefix "test_auto_disable" {
+ test_auto_disable
+}
diff --git a/gdb/testsuite/gdb.python/py-breakpoint.exp b/gdb/testsuite/gdb.python/py-breakpoint.exp
index e2ffe8cbe46..e9102e7e3ea 100644
--- a/gdb/testsuite/gdb.python/py-breakpoint.exp
+++ b/gdb/testsuite/gdb.python/py-breakpoint.exp
@@ -799,6 +799,26 @@ proc_with_prefix test_catchpoints {} {
gdb_test "continue" "Stopped at catchpoint event: ${num}"
}

+proc_with_prefix test_bkpt_auto_disable { } {
+ global srcfile testfile hex decimal
+
+ # Start with a fresh gdb.
+ clean_restart ${testfile}
+
+ if ![runto_main] then {
+ fail "cannot run to main."
+ return 0
+ }
+ delete_breakpoints
+
+ set mult_line [gdb_get_line_number "Break at multiply."]
+ gdb_breakpoint ${mult_line}
+ gdb_test "enable count 1 2" "" "One shot enable."
+ gdb_test "python gdb.events.breakpoint_modified.connect(lambda bp: print(bp.enabled))" \
+ "" "Trap breakpoint_modified event"
+ gdb_test "continue" "False.*" "auto-disabling after enable count reached"
+}
+
test_bkpt_basic
test_bkpt_deletion
test_bkpt_cond_and_cmds
@@ -815,3 +835,4 @@ test_bkpt_events
test_bkpt_explicit_loc
test_bkpt_qualified
test_bkpt_probe
+test_bkpt_auto_disable
--
2.31.1