Merge pull request #258 from spyoungtech/gh-257

Add AHK process handling to exit if parent Python process dies unexpectedly

ahk/_constants.py

@@ -2756,6 +2756,7 @@
 
 {% endfor %}
 ; END extension scripts
+
 {% block before_autoexecute %}
 {% endblock before_autoexecute %}
 
@@ -2765,6 +2766,15 @@
 
 Loop {
     query := RTrim(stdin.ReadLine(), "`n")
+    if (query = "") {
+        ; Technically this should only happen if the Python process has died, so sending a message is probably futile
+        ; But if this somehow triggers in some other case, we'll try to have an informative error raised.
+        pyresp := FormatResponse("ahk.message.ExceptionResponseMessage", "Unexpected empty message; AHK exiting. This is likely a bug. Please report this issue at https://github.com/spyoungtech/ahk/issues")
+        FileAppend, %pyresp%, *, UTF-8
+
+        ; Exit to avoid leaving the process hanging around needlessly
+        ExitApp
+    }
     argsArray := CommandArrayFromQuery(query)
     try {
         func := argsArray[1]
@@ -2796,6 +2806,7 @@
 
 HOTKEYS_SCRIPT_TEMPLATE = r"""#Requires AutoHotkey v1.1.17+
 #Persistent
+
 {% for directive in directives %}
 {% if directive.apply_to_hotkeys_process %}
 
@@ -2807,7 +2818,8 @@
 OnClipboardChange("ClipChanged")
 {% endif %}
 KEEPALIVE := Chr(57344)
-SetTimer, keepalive, 1000
+stdin  := FileOpen("*", "r `n", "UTF-8")
+SetTimer, keepalive, 2000
 
 Crypt32 := DllCall("LoadLibrary", "Str", "Crypt32.dll", "Ptr")
 
@@ -2892,8 +2904,16 @@
 
 
 keepalive:
-global KEEPALIVE
-FileAppend, %KEEPALIVE%`n, *, UTF-8
+    global KEEPALIVE
+    global stdin
+    FileAppend, %KEEPALIVE%`n, *, UTF-8
+    alive_message := RTrim(stdin.ReadLine(), "`n")
+    if (alive_message != KEEPALIVE) {
+        ; The parent Python process has terminated unexpectedly
+        ; Exit to avoid leaving the hotkey process around
+        ExitApp
+    }
+    return
 
 """
 
@@ -5744,6 +5764,15 @@
 
 Loop {
     query := RTrim(stdin.ReadLine(), "`n")
+    if (query = "") {
+        ; Technically, this should only happen if the Python process has died, so sending a message is probably futile
+        ; But if this somehow triggers in some other case and the Python process is still listening, we'll try to have an informative error raised.
+        pyresp := FormatResponse("ahk.message.ExceptionResponseMessage", "Unexpected empty message; AHK exiting. This is likely a bug. Please report this issue at https://github.com/spyoungtech/ahk/issues")
+        stdout.Write(pyresp)
+        stdout.Read(0)
+        ; Exit to avoid leaving the process hanging around
+        ExitApp
+    }
     argsArray := CommandArrayFromQuery(query)
     try {
         func_name := argsArray[1]
@@ -5786,9 +5815,9 @@
 
 
 KEEPALIVE := Chr(57344)
-;SetTimer, keepalive, 1000
 
 stdout := FileOpen("*", "w", "UTF-8")
+stdin  := FileOpen("*", "r `n", "UTF-8")
 
 WriteStdout(s) {
     global stdout
@@ -5883,10 +5912,19 @@
 OnClipboardChange(ClipChanged)
 
 {% endif %}
-
-
-;keepalive:
-;global KEEPALIVE
-;FileAppend, %KEEPALIVE%`n, *, UTF-8
+SetTimer KeepAliveFunc, 2000
+
+KeepAliveFunc() {
+    global stdin
+    global KEEPALIVE
+    WriteStdout(Format("{}`n", KEEPALIVE))
+    alive_message := RTrim(stdin.ReadLine(), "`n")
+    if (alive_message != KEEPALIVE) {
+        ; The parent Python process has terminated unexpectedly
+        ; Exit to avoid leaving the hotkey process around
+        ExitApp
+    }
+    return
+}
 
 """

ahk/_hotkey.py

@@ -336,11 +336,14 @@ def listener(self) -> None:
                 stderr=subprocess.STDOUT,
             )
             atexit.register(kill, self._proc)
+            assert self._proc.stdout is not None
+            assert self._proc.stdin is not None
             while self._running:
-                assert self._proc.stdout is not None
                 line = self._proc.stdout.readline()
                 if line.rstrip(b'\n') == _KEEPALIVE_SENTINEL:
                     logging.debug('keepalive received')
+                    self._proc.stdin.write(b'\xee\x80\x80\n')
+                    self._proc.stdin.flush()
                     continue
                 if not line.strip():
                     logging.debug('Listener: Process probably died, exiting')

ahk/templates/daemon-v2.ahk

@@ -2845,6 +2845,15 @@ pyresp := ""
 
 Loop {
     query := RTrim(stdin.ReadLine(), "`n")
+    if (query = "") {
+        ; Technically, this should only happen if the Python process has died, so sending a message is probably futile
+        ; But if this somehow triggers in some other case and the Python process is still listening, we'll try to have an informative error raised.
+        pyresp := FormatResponse("ahk.message.ExceptionResponseMessage", "Unexpected empty message; AHK exiting. This is likely a bug. Please report this issue at https://github.com/spyoungtech/ahk/issues")
+        stdout.Write(pyresp)
+        stdout.Read(0)
+        ; Exit to avoid leaving the process hanging around
+        ExitApp
+    }
     argsArray := CommandArrayFromQuery(query)
     try {
         func_name := argsArray[1]

ahk/templates/daemon.ahk

@@ -2753,6 +2753,7 @@ CommandArrayFromQuery(ByRef text) {
 
 {% endfor %}
 ; END extension scripts
+
 {% block before_autoexecute %}
 {% endblock before_autoexecute %}
 
@@ -2762,6 +2763,15 @@ pyresp := ""
 
 Loop {
     query := RTrim(stdin.ReadLine(), "`n")
+    if (query = "") {
+        ; Technically this should only happen if the Python process has died, so sending a message is probably futile
+        ; But if this somehow triggers in some other case, we'll try to have an informative error raised.
+        pyresp := FormatResponse("ahk.message.ExceptionResponseMessage", "Unexpected empty message; AHK exiting. This is likely a bug. Please report this issue at https://github.com/spyoungtech/ahk/issues")
+        FileAppend, %pyresp%, *, UTF-8
+
+        ; Exit to avoid leaving the process hanging around needlessly
+        ExitApp
+    }
     argsArray := CommandArrayFromQuery(query)
     try {
         func := argsArray[1]

ahk/templates/hotkeys-v2.ahk

@@ -8,9 +8,9 @@
 
 
 KEEPALIVE := Chr(57344)
-;SetTimer, keepalive, 1000
 
 stdout := FileOpen("*", "w", "UTF-8")
+stdin  := FileOpen("*", "r `n", "UTF-8")
 
 WriteStdout(s) {
     global stdout
@@ -105,8 +105,17 @@ ClipChanged(Type) {
 OnClipboardChange(ClipChanged)
 
 {% endif %}
-
-
-;keepalive:
-;global KEEPALIVE
-;FileAppend, %KEEPALIVE%`n, *, UTF-8
+SetTimer KeepAliveFunc, 2000
+
+KeepAliveFunc() {
+    global stdin
+    global KEEPALIVE
+    WriteStdout(Format("{}`n", KEEPALIVE))
+    alive_message := RTrim(stdin.ReadLine(), "`n")
+    if (alive_message != KEEPALIVE) {
+        ; The parent Python process has terminated unexpectedly
+        ; Exit to avoid leaving the hotkey process around
+        ExitApp
+    }
+    return
+}

ahk/templates/hotkeys.ahk

@@ -1,5 +1,6 @@
 #Requires AutoHotkey v1.1.17+
 #Persistent
+
 {% for directive in directives %}
 {% if directive.apply_to_hotkeys_process %}
 
@@ -11,7 +12,8 @@
 OnClipboardChange("ClipChanged")
 {% endif %}
 KEEPALIVE := Chr(57344)
-SetTimer, keepalive, 1000
+stdin  := FileOpen("*", "r `n", "UTF-8")
+SetTimer, keepalive, 2000
 
 Crypt32 := DllCall("LoadLibrary", "Str", "Crypt32.dll", "Ptr")
 
@@ -96,5 +98,13 @@ ClipChanged(Type) {
 
 
 keepalive:
-global KEEPALIVE
-FileAppend, %KEEPALIVE%`n, *, UTF-8
+    global KEEPALIVE
+    global stdin
+    FileAppend, %KEEPALIVE%`n, *, UTF-8
+    alive_message := RTrim(stdin.ReadLine(), "`n")
+    if (alive_message != KEEPALIVE) {
+        ; The parent Python process has terminated unexpectedly
+        ; Exit to avoid leaving the hotkey process around
+        ExitApp
+    }
+    return

docs/README.md

@@ -35,7 +35,8 @@ print(ahk.mouse_position)  #  (150, 150)
 
 # Examples
 
-Non-exhaustive examples of some functions available with this package. Full documentation coming soon!
+Non-exhaustive examples of some functions available with this package. See the [full documentation](https://ahk.readthedocs.io/en/latest/?badge=latest)
+for complete API references and additional features.
 
 ## Hotkeys