Add cross-platform support to decky (#387)

* Import generic watchdog observer over platform specific import

* Use os.path rather than genericpath

* Split off socket management in plugin.py

* Don't specify multiprocessing start type

Default on linux is already fork

* Move all platform-specific functions to seperate files

TODO: make plugin.py platform agnostic

* fix import

* add backwards compat to helpers.py

* add backwards compatibility to helpers.py harder

* Testing autobuild for win

* Testing autobuild for win, try 2

* Testing autobuild for win, try 3

* Testing autobuild for win, try 4

* Create the plugins folder before attempting to use it

* Implement win get_username()

* Create win install script

* Fix branch guess from version

* Create .loader.version in install script

* Add .cmd shim to facilitate auto-restarts

* Properly fix branch guess from version

* Fix updater on windows

* Try 2 of fixing updates for windows

* Test

* pain

* Update install script

* Powershell doesn't believe in utf8

* Powershell good

* add ON_LINUX variable to localplatform

* Fix more merge issues

* test

* Move custom imports to main.py

* Move custom imports to after __main__ check 

Due to windows' default behaviour being spawn, it will spawn a new process and thus import into sys.path multiple times

* Log errors in get_system_pythonpaths() and get_loader_version() + 

split get_system_pythonpaths() on newline

* Remove whitespace in result of get_system_pythonpaths()

* use python3 on linux and python on windows in get_system_pythonpaths()

* Remove fork-specific urls

* Fix MIME types not working on Windows

1 files changed, 132 insertions, 0 deletions

diff --git a/backend/localsocket.py b/backend/localsocket.py
new file mode 100644
index 00000000..ef0e3933
--- /dev/null
+++ b/backend/localsocket.py
@@ -0,0 +1,132 @@
+import asyncio, time, random
+from localplatform import ON_WINDOWS
+
+BUFFER_LIMIT = 2 ** 20  # 1 MiB
+
+class UnixSocket:
+    def __init__(self, on_new_message):
+        '''
+        on_new_message takes 1 string argument.
+        It's return value gets used, if not None, to write data to the socket.
+        Method should be async
+        '''
+        self.socket_addr = f"/tmp/plugin_socket_{time.time()}"
+        self.on_new_message = on_new_message
+        self.socket = None
+        self.reader = None
+        self.writer = None
+
+    async def setup_server(self):
+        self.socket = await asyncio.start_unix_server(self._listen_for_method_call, path=self.socket_addr, limit=BUFFER_LIMIT)
+    
+    async def _open_socket_if_not_exists(self):
+        if not self.reader:
+            retries = 0
+            while retries < 10:
+                try:
+                    self.reader, self.writer = await asyncio.open_unix_connection(self.socket_addr, limit=BUFFER_LIMIT)
+                    return True
+                except:
+                    await asyncio.sleep(2)
+                    retries += 1
+            return False
+        else:
+            return True
+
+    async def get_socket_connection(self):
+        if not await self._open_socket_if_not_exists():
+            return None, None
+        
+        return self.reader, self.writer
+    
+    async def close_socket_connection(self):
+        if self.writer != None:
+            self.writer.close()
+
+        self.reader = None
+
+    async def read_single_line(self) -> str|None:
+        reader, writer = await self.get_socket_connection()
+
+        if self.reader == None:
+            return None
+
+        return await self._read_single_line(reader)
+
+    async def write_single_line(self, message : str):
+        reader, writer = await self.get_socket_connection()
+
+        if self.writer == None:
+            return;
+
+        await self._write_single_line(writer, message)
+
+    async def _read_single_line(self, reader) -> str:
+        line = bytearray()
+        while True:
+            try:
+                line.extend(await reader.readuntil())
+            except asyncio.LimitOverrunError:
+                line.extend(await reader.read(reader._limit))
+                continue
+            except asyncio.IncompleteReadError as err:
+                line.extend(err.partial)
+                break
+            else:
+                break
+
+        return line.decode("utf-8")
+    
+    async def _write_single_line(self, writer, message : str):
+        if not message.endswith("\n"):
+            message += "\n"
+
+        writer.write(message.encode("utf-8"))
+        await writer.drain()
+
+    async def _listen_for_method_call(self, reader, writer):
+        while True:
+            line = await self._read_single_line(reader)
+
+            try:
+                res = await self.on_new_message(line)
+            except Exception as e:
+                return
+
+            if res != None:
+                await self._write_single_line(writer, res)
+            
+class PortSocket (UnixSocket):
+    def __init__(self, on_new_message):
+        '''
+        on_new_message takes 1 string argument.
+        It's return value gets used, if not None, to write data to the socket.
+        Method should be async
+        '''
+        super().__init__(on_new_message)
+        self.host = "127.0.0.1"
+        self.port = random.sample(range(40000, 60000), 1)[0]
+    
+    async def setup_server(self):
+        self.socket = await asyncio.start_server(self._listen_for_method_call, host=self.host, port=self.port, limit=BUFFER_LIMIT)
+    
+    async def _open_socket_if_not_exists(self):
+        if not self.reader:
+            retries = 0
+            while retries < 10:
+                try:
+                    self.reader, self.writer = await asyncio.open_connection(host=self.host, port=self.port, limit=BUFFER_LIMIT)
+                    return True
+                except:
+                    await asyncio.sleep(2)
+                    retries += 1
+            return False
+        else:
+            return True
+
+if ON_WINDOWS:
+    class LocalSocket (PortSocket): 
+        pass
+else:
+    class LocalSocket (UnixSocket):
+        pass
\ No newline at end of file