[gdb/dap] Fix race between dap exit and gdb exit
When DAP shuts down due to an EOF event, there's a race between:
- gdb's main thread handling a SIGHUP, and
- the DAP main thread exiting.
Fix this by waiting for DAP's main thread exit during the gdb_exiting event.
Tested on aarch64-linux.
Approved-By: Tom Tromey <tom@tromey.com>
PR dap/31380
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31380
diff --git a/gdb/python/lib/gdb/dap/startup.py b/gdb/python/lib/gdb/dap/startup.py
index 29fe78e..a2b6899 100644
--- a/gdb/python/lib/gdb/dap/startup.py
+++ b/gdb/python/lib/gdb/dap/startup.py
@@ -93,7 +93,15 @@
_dap_thread = threading.current_thread()
target()
- start_thread("DAP", really_start_dap)
+ # Note: unlike _dap_thread, dap_thread is a local variable.
+ dap_thread = start_thread("DAP", really_start_dap)
+
+ def _on_gdb_exiting(event):
+ thread_log("joining DAP thread ...")
+ dap_thread.join()
+ thread_log("joining DAP thread done")
+
+ gdb.events.gdb_exiting.connect(_on_gdb_exiting)
def in_gdb_thread(func):
diff --git a/gdb/testsuite/gdb.dap/eof.exp b/gdb/testsuite/gdb.dap/eof.exp
index a84b1d2..05048f2 100644
--- a/gdb/testsuite/gdb.dap/eof.exp
+++ b/gdb/testsuite/gdb.dap/eof.exp
@@ -38,3 +38,12 @@
# Check that first log message is present.
dap_check_log_file_re [string_to_regexp "starting DAP server"]
+
+# There should be one "READ:" for the initialize request, and at least one
+# "WROTE:" for the initialize response.
+dap_check_log_file_re "READ:"
+dap_check_log_file_re "WROTE:"
+
+# Check that all thread termination messages are there.
+dap_check_log_file_re "JSON writer: terminating"
+dap_check_log_file_re "DAP: terminating"
