tests: the quit tests wait for the GUI's window before sending SIGTERM

tests/ui-smoke/_lib/quit-launch.sh

@@ -3,9 +3,9 @@
 # Usage: quit-launch.sh <sim-config-ini> <gui-process-match>
 #
 # Boots linuxcnc + GUI under xvfb-run exactly like launch.sh, waits for
-# the NML task to come up (via drive.py), then sends SIGTERM to the GUI
-# process *alone* and asserts the GUI exits on its own within a short
-# grace. This is the regression guard for the SIGTERM clean-shutdown
+# the NML task to come up (via drive.py) and for the GUI to put a window
+# on the screen, then sends SIGTERM to the GUI process *alone* and
+# asserts the GUI exits on its own within a short grace. This is the regression guard for the SIGTERM clean-shutdown
 # handlers: a GUI that absorbs SIGTERM and has to be SIGKILLed fails.
 #
 # <gui-process-match> is a pgrep -f pattern identifying the GUI process
@@ -14,7 +14,7 @@
 #
 # Markers (consumed by checkresult-quit.sh):
 #   UI_SMOKE_QUIT_OK    GUI exited on SIGTERM within QUIT_GRACE
-#   UI_SMOKE_QUIT_FAIL  GUI never started, was not found, or ignored TERM
+#   UI_SMOKE_QUIT_FAIL  GUI never started, showed no window, or ignored TERM
 
 set -u
 
@@ -24,7 +24,7 @@ TEST_DIR="${TEST_DIR:-$(cd "$(dirname "$0")" && pwd)}"
 LIB_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
 
 cd "$TEST_DIR" || exit 1
-rm -f ui-smoke.out ui-smoke.err linuxcnc.pid
+rm -f ui-smoke.out ui-smoke.err ui-smoke-qt.png linuxcnc.pid
 
 bash "$LIB_DIR/cleanup-runtime.sh"
 
@@ -34,6 +34,9 @@ DRIVER_TIMEOUT=90
 # stuck. A GUI honouring SIGTERM exits in well under a second; the
 # margin covers Cleanup of task/motion on slow CI.
 QUIT_GRACE=15
+# Seconds to wait, after task is reachable, for the GUI to show a window
+# before declaring it never came up.
+GUI_UP_TIMEOUT=60
 
 # Shared headless environment (software GL + audio silencing), kept in
 # launch-env.sh so launch.sh and quit-launch.sh cannot drift apart.
@@ -47,7 +50,7 @@ crashdump_arm
 # shell's cwd); see launch.sh for why a relative name would miss.
 export UI_SMOKE_QT_SHOT="$PWD/ui-smoke-qt.png"
 
-export CONFIG_INI LIB_DIR DRIVER_TIMEOUT GUI_MATCH QUIT_GRACE
+export CONFIG_INI LIB_DIR DRIVER_TIMEOUT GUI_MATCH QUIT_GRACE GUI_UP_TIMEOUT
 
 # shellcheck disable=SC2016
 xvfb-run -a --server-args="-screen 0 $UI_SMOKE_XVFB_SCREEN" \
@@ -57,8 +60,8 @@ xvfb-run -a --server-args="-screen 0 $UI_SMOKE_XVFB_SCREEN" \
         LINUXCNC_PID=$!
         echo "$LINUXCNC_PID" >linuxcnc.pid
 
-        # Wait until the task is reachable (GUI has constructed and the
-        # NML round-trip works). Reuse the phase-1 driver for readiness.
+        # Wait until the task is reachable (the NML round-trip works).
+        # Reuse the phase-1 driver for readiness.
         timeout "$DRIVER_TIMEOUT" python3 "$LIB_DIR/drive.py" >ui-smoke.out 2>ui-smoke.err
         if ! grep -q "^UI_SMOKE_OK$" ui-smoke.out; then
             echo "UI_SMOKE_QUIT_FAIL: GUI did not come up; cannot test quit"
@@ -67,26 +70,78 @@ xvfb-run -a --server-args="-screen 0 $UI_SMOKE_XVFB_SCREEN" \
             exit 1
         fi
 
-        # Identify the GUI process. pgrep -f matches against the whole
-        # command line, so wrapper processes (the linuxcnc launcher, the
-        # xvfb-run shell, this bash -c) also match because the GUI name
-        # appears in the config path or the embedded script text. Every
-        # such wrapper has a shell or xvfb-run as argv[0]; the real GUI
-        # is a python interpreter. Pick the first match whose argv[0]
-        # basename is a python binary.
+        # Task being reachable says nothing about the GUI: the launcher
+        # starts it after task, and on a loaded runner it can still be
+        # importing, or constructing, seconds later. A SIGTERM there
+        # tests startup, not quit. Wait for the process, then for a
+        # window of its own on the screen: that is a GUI running.
+        #
+        # pgrep -f matches against the whole command line, so wrapper
+        # processes (the linuxcnc launcher, the xvfb-run shell, this
+        # bash -c) also match because the GUI name appears in the config
+        # path or the embedded script text. Every such wrapper has a
+        # shell or xvfb-run as argv[0]; the real GUI is a python
+        # interpreter. Pick the first match whose argv[0] basename is a
+        # python binary.
+        find_gui_pid() {
+            for p in $(pgrep -f "$GUI_MATCH"); do
+                arg0=$(tr "\0" "\n" <"/proc/$p/cmdline" 2>/dev/null | head -1)
+                case "$(basename "$arg0" 2>/dev/null)" in
+                    python*) echo "$p"; return 0 ;;
+                esac
+            done
+            return 1
+        }
+        # A viewable top-level window whose _NET_WM_PID is the GUI. GTK
+        # and Qt both set the property; xvfb runs no window manager, so
+        # top-levels are children of the root window.
+        #
+        # Offscreen Qt never draws to the X server. Its shim saves a
+        # self-grab on SIGUSR1, and only once a top-level is visible, so
+        # the grab file appearing is the same signal. The shim installs
+        # the handler at interpreter startup; until then SIGUSR1 would
+        # kill the process, so ask only once /proc says it is caught.
+        gui_window_up() {
+            if [ "${QT_QPA_PLATFORM:-}" = "offscreen" ]; then
+                [ -s "$UI_SMOKE_QT_SHOT" ] && return 0
+                caught=$(awk "/^SigCgt:/{print \$2}" "/proc/$1/status" 2>/dev/null)
+                if [ -n "$caught" ] && [ $(( 0x$caught >> 9 & 1 )) -eq 1 ]; then
+                    kill -USR1 "$1" 2>/dev/null || true
+                fi
+                return 1
+            fi
+            for w in $(xwininfo -root -children 2>/dev/null | grep -oE "^ +0x[0-9a-f]+"); do
+                xprop -id "$w" _NET_WM_PID 2>/dev/null | grep -q "= $1\$" || continue
+                xwininfo -id "$w" 2>/dev/null | grep -q "Map State: IsViewable" && return 0
+            done
+            return 1
+        }
         GUI_PID=""
-        for p in $(pgrep -f "$GUI_MATCH"); do
-            arg0=$(tr "\0" "\n" <"/proc/$p/cmdline" 2>/dev/null | head -1)
-            case "$(basename "$arg0" 2>/dev/null)" in
-                python*) GUI_PID="$p"; break ;;
-            esac
+        waited=0
+        while [ "$waited" -lt "$GUI_UP_TIMEOUT" ]; do
+            [ -n "$GUI_PID" ] || GUI_PID=$(find_gui_pid)
+            if [ -n "$GUI_PID" ] && gui_window_up "$GUI_PID"; then
+                break
+            fi
+            kill -0 "$LINUXCNC_PID" 2>/dev/null || break
+            sleep 1
+            waited=$((waited + 1))
         done
         if [ -z "$GUI_PID" ]; then
             echo "UI_SMOKE_QUIT_FAIL: GUI process matching \"$GUI_MATCH\" not found"
             kill -KILL -- -"$LINUXCNC_PID" 2>/dev/null || true
             bash "$LIB_DIR/cleanup-runtime.sh"
             exit 1
         fi
+        if [ "$waited" -ge "$GUI_UP_TIMEOUT" ]; then
+            echo "UI_SMOKE_QUIT_FAIL: GUI (pid $GUI_PID) showed no window within ${GUI_UP_TIMEOUT}s"
+            . "$LIB_DIR/screenshot.sh"
+            screenshot_grab screenshot.png
+            kill -KILL -- -"$LINUXCNC_PID" 2>/dev/null || true
+            bash "$LIB_DIR/cleanup-runtime.sh"
+            exit 1
+        fi
+        echo "GUI (pid $GUI_PID) up with a window after ${waited}s"
 
         # Send SIGTERM to the GUI alone and time how long it takes to go.
         kill -TERM "$GUI_PID" 2>/dev/null || true