Cleanup and reorganize platform specific stuff, use unlink for close on POSIX, fix ConEmu adapter

pokemonterminal/main.py

@@ -11,7 +11,7 @@ from . import scripter, slideshow
 from pokemonterminal.command_flags import parser, is_slideshow
 from pokemonterminal.database import Database
 from pokemonterminal.filters import Filter
-from pokemonterminal.platform.named_event import create_named_event
+from pokemonterminal.platform import PlatformNamedEvent
 
 
 
@@ -69,40 +69,39 @@ def main(argv=None):
         print("Dry run, exiting.")
         return
 
-    e = create_named_event("Pokemon-Terminal_Wallpaper" if options.wallpaper else "Pokemon-Terminal_Terminal")
-    try:
-        if options.clear:
-            if e.is_duplicate():
-                e.set()
-            scripter.clear_terminal()
-            return
+    event_name = "Pokemon-Terminal_Wallpaper" if options.wallpaper else "Pokemon-Terminal_Terminal"
+    event_exists = PlatformNamedEvent.exists(event_name)
 
-        if is_slideshow and options.id <= 0 and size > 1:
-            if e.is_duplicate():
-                print("One or more slideshows is already running.\n")
-                while True:
-                    print("[S]top the previous slideshow(s) / ", end='')
-                    if not options.wallpaper:
-                        print("[I]gnore and continue / ", end='')
-                    print("[A]bort")
-                    inp = input("Pick one: ").lower() # FIXME weird bug: inputting s here doesn't actually close the older process but "pokemon -c" does
-                    if inp == 's':
-                        e.set()
-                        break
-                    elif inp == 'i' and not options.wallpaper:
-                        break
-                    elif inp == 'a':
-                        return
-                    else:
-                        print("Not a valid option!\n")
-            if options.slideshow <= 0:
-                print("Time has to be greater then 0. You can use decimal values.")
-                return
-            e.clear()
-            target_func = scripter.change_wallpaper if options.wallpaper else scripter.change_terminal
-            slideshow.start(Filter.filtered_list, options.slideshow, target_func, e.name())
-    finally:
-        e.close()
+    if options.clear:
+        if event_exists:
+            slideshow.stop(event_name)
+        if not options.wallpaper:
+            scripter.clear_terminal()
+        return
+
+    if is_slideshow and options.id <= 0 and size > 1:
+        if event_exists:
+            print("One or more slideshows is already running.\n")
+            while True:
+                print("[S]top the previous slideshow(s) / ", end='')
+                if not options.wallpaper:
+                    print("[I]gnore and continue / ", end='')
+                print("[A]bort")
+                inp = input("Pick one: ").lower()
+                if inp == 's':
+                    slideshow.stop(event_name)
+                    break
+                elif inp == 'i' and not options.wallpaper:
+                    break
+                elif inp == 'a':
+                    return
+                else:
+                    print("Not a valid option!\n")
+        if options.slideshow <= 0:
+            print("Time has to be greater then 0. You can use decimal values.")
+            return
+        target_func = scripter.change_wallpaper if options.wallpaper else scripter.change_terminal
+        slideshow.start(Filter.filtered_list, options.slideshow, target_func, event_name)
 
     if options.wallpaper:
         scripter.change_wallpaper(target.get_path())

pokemonterminal/platform/__init__.py

@@ -0,0 +1,8 @@
+import sys
+
+if sys.platform == 'win32':
+    from .named_event.win import WindowsNamedEvent as platform_event
+else:
+    from .named_event.posix import PosixNamedEvent as platform_event
+
+PlatformNamedEvent = platform_event

pokemonterminal/platform/named_event/__init__.py

@@ -1,11 +1,67 @@
-import sys
+from abc import ABC, abstractmethod
 
-from .adapters import NamedEvent
+class NamedEvent(ABC):
+    """
+    Interface representing an operating system event object with a name.
+    """
 
-def create_named_event(name: str) -> NamedEvent:
-    if sys.platform == 'win32':
-        from .adapters.win import WindowsNamedEvent
-        return WindowsNamedEvent(name)
-    else:
-        from .adapters.posix import PosixNamedEvent
-        return PosixNamedEvent(name)
+    @staticmethod
+    @abstractmethod
+    def exists(name: str) -> bool:
+        """
+        check if event exists
+        does not returns event, use the constructor for that.
+        :return a boolean indicating wether the event exists.
+        """
+        pass
+
+    @abstractmethod
+    def is_set(self) -> bool:
+        """
+        check if event set
+        :return a boolean indicating wether the event has been set.
+        """
+        pass
+
+    @abstractmethod
+    def set(self):
+        """
+        sets the event
+        """
+        pass
+
+    @abstractmethod
+    def clear(self):
+        """
+        resets the event
+        """
+        pass
+
+    @abstractmethod
+    def wait(self, timeout=None):
+        """
+        block until event is set
+        :param timeout Optional timeout for wait in seconds.
+        """
+        pass
+
+    @abstractmethod
+    def name(self) -> str:
+        """
+        gets the name set at creation of the event
+        :return Name of the event
+        """
+        pass
+
+    @abstractmethod
+    def close(self):
+        """
+        release native resources
+        """
+        pass
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, exc_type, exc_value, traceback):
+        self.close()

pokemonterminal/platform/named_event/adapters/__init__.py

@@ -1,59 +0,0 @@
-from abc import ABC, abstractmethod
-
-class NamedEvent(ABC):
-    """
-    Interface representing an operating system event object with a name.
-    """
-
-    @abstractmethod
-    def is_set(self) -> bool:
-        """
-        check if event set
-        :return a boolean indicating wether the event has been set.
-        """
-        pass
-
-    @abstractmethod
-    def set(self):
-        """
-        sets the event
-        """
-        pass
-
-    @abstractmethod
-    def clear(self):
-        """
-        resets the event
-        """
-        pass
-
-    @abstractmethod
-    def wait(self, timeout=None):
-        """
-        block until event is set
-        :param timeout Optional timeout for wait in seconds.
-        """
-        pass
-
-    @abstractmethod
-    def is_duplicate(self) -> bool:
-        """
-        determines if the event was created or opened as a result of creating this class
-        :return True if it was opened. False if it was created.
-        """
-        pass
-
-    @abstractmethod
-    def name(self) -> str:
-        """
-        gets the name set at creation of the event
-        :return Name of the event
-        """
-        pass
-
-    @abstractmethod
-    def close(self):
-        """
-        release native resources
-        """
-        pass

pokemonterminal/platform/named_event/posix.py

@@ -7,14 +7,19 @@ class PosixNamedEvent(NamedEvent):
     A wrapper for named events using a named semaphore
     """
 
-    def __init__(self, name: str):
+    def exists(name: str) -> bool:
         semaphore_name = '/' + name
         try:
-            self.__semaphore = posix_ipc.Semaphore(semaphore_name, flags=posix_ipc.O_CREX)
-            self.__duplicate = False
+            semaphore = posix_ipc.Semaphore(semaphore_name)
+            semaphore.close()
+            return True
         except posix_ipc.ExistentialError: # Semaphores are reconsidering their life choices
-            self.__semaphore = posix_ipc.Semaphore(semaphore_name)
-            self.__duplicate = True
+            return False
+
+
+    def __init__(self, name: str):
+        semaphore_name = '/' + name
+        self.__semaphore = posix_ipc.Semaphore(semaphore_name, flags=posix_ipc.O_CREAT)
 
     # NOTE this doesn't works on macOS, see http://semanchuk.com/philip/posix_ipc/#platforms
     def is_set(self) -> bool:
@@ -37,11 +42,9 @@ class PosixNamedEvent(NamedEvent):
         except posix_ipc.BusyError:
             return
 
-    def is_duplicate(self) -> bool:
-        return self.__duplicate
-
     def name(self) -> str:
         return self.__semaphore.name
 
     def close(self):
-        self.__semaphore.close()
+        # FIXME do we also need to close it here?
+        self.__semaphore.unlink()

pokemonterminal/platform/named_event/win.py

@@ -7,21 +7,36 @@ class WindowsNamedEvent(NamedEvent):
     Named events using the native Windows APIs
     """
 
+    __SYNCHRONIZE = 0x00100000
+    __EVENT_MODIFY_STATE = 2
+
     __WAIT_OBJECT_0 = 0
     __WAIT_FAILED = 0xFFFFFFFF
 
-    __ERROR_ALREADY_EXISTS = 183
+    __ERROR_FILE_NOT_FOUND = 2
 
     def __raise_last_error():
         err_no = ctypes.GetLastError()
         raise WindowsError(err_no, ctypes.FormatError(err_no))
 
+    def exists(name: str) -> bool:
+        event = ctypes.windll.kernel32.OpenEventW(WindowsNamedEvent.__SYNCHRONIZE | WindowsNamedEvent.__EVENT_MODIFY_STATE, False, name)
+        if event == 0:
+            if ctypes.GetLastError() == WindowsNamedEvent.__ERROR_FILE_NOT_FOUND:
+                return False
+            else:
+                WindowsNamedEvent.__raise_last_error()
+        else:
+            result = ctypes.windll.kernel32.CloseHandle(event)
+            if result == 0:
+                WindowsNamedEvent.__raise_last_error()
+            return True
+
     def __init__(self, name: str):
         event = ctypes.windll.kernel32.CreateEventW(ctypes.c_void_p(), True, False, name)
         if event == 0:
             WindowsNamedEvent.__raise_last_error()
 
-        self.__duplicate = ctypes.GetLastError() == WindowsNamedEvent.__ERROR_ALREADY_EXISTS
         self.__event = event
         self.__name = name
 
@@ -47,9 +62,6 @@ class WindowsNamedEvent(NamedEvent):
         if result == WindowsNamedEvent.__WAIT_FAILED:
             WindowsNamedEvent.__raise_last_error()
 
-    def is_duplicate(self) -> bool:
-        return self.__duplicate
-
     def name(self) -> str:
         return self.__name
 

pokemonterminal/slideshow.py

@@ -2,7 +2,7 @@ import atexit
 import random
 import sys
 
-from .platform.named_event import create_named_event
+from .platform import PlatformNamedEvent
 
 def __print_fork(pid, length, delay):
     print(f"Starting slideshow with {length} Pokemons and a delay of {delay} minutes.")
@@ -27,8 +27,7 @@ def __get_sleeper_and_listener(event):
     return sleeper, listener
 
 def __slideshow_worker(filtered, delay, changer_func, event_name):
-    e = create_named_event(event_name)
-    try:
+    with PlatformNamedEvent(event_name) as e:
         sleeper, listener = __get_sleeper_and_listener(e)
         random.shuffle(filtered)
         queque = iter(filtered)
@@ -40,8 +39,6 @@ def __slideshow_worker(filtered, delay, changer_func, event_name):
                 continue
             changer_func(next_pkmn.get_path())
             sleeper(delay * 60)
-    finally:
-        e.close()
 
 def start(filtered, delay, changer_func, event_name):
     if sys.platform == 'win32':
@@ -58,4 +55,8 @@ def start(filtered, delay, changer_func, event_name):
         if pid > 0:
             __print_fork(pid, len(filtered), delay)
             sys.exit(0)
-        __slideshow_worker(filtered, delay, changer_func, event_name)
+        __slideshow_worker(filtered, delay, changer_func, event_name)
+
+def stop(event_name):
+    with PlatformNamedEvent(event_name) as e:
+        e.set()

pokemonterminal/terminal/adapters/conemu.py

@@ -11,7 +11,7 @@ class ConEmuProvider(_TProv):
         return "CONEMUPID" in os.environ
 
     def __run_command(command: str):
-        output = subprocess.check_output(["ConEmuC", "-GuiMacro", command]).decode(sys.stdout.encoding)
+        output = subprocess.check_output(f"ConEmuC -GuiMacro {command}", shell=True).decode(sys.stdout.encoding)
         if output != 'OK':
             print(output)