moved the main message loop entirely into Python

scripts/tmp_main.py

@@ -1,6 +1,9 @@
 # Initial test script
 import upiwin_tmp
 
+def log_touch(event, x, y):
+	print("Touch {0} at ({1), {2})\n".format(event, x, y))
+
 upiwin_tmp.filled_rectangle(10, 10, 50, 50, upiwin_tmp.FBPRIMCLR_RED, False)
 upiwin_tmp.filled_rectangle(60, 10, 100, 50, upiwin_tmp.FBPRIMCLR_GREEN, False)
 upiwin_tmp.filled_rectangle(110, 10, 150, 50, upiwin_tmp.FBPRIMCLR_BLUE, False)
@@ -14,3 +17,26 @@ upiwin_tmp.line(10, 150, 150, 110, upiwin_tmp.FBPRIMCLR_WHITE, False)
 upiwin_tmp.line(0, 180, 319, 180, upiwin_tmp.FBPRIMCLR_RED, False);
 upiwin_tmp.line(0, 196, 319, 196, upiwin_tmp.FBPRIMCLR_RED, False);
 upiwin_tmp.textout(10, 180, 'Amy was here!!!')
+
+msg = {}
+while upiwin.get_message(msg):
+	if msg['message'] == upiwin.WM_HWBUTTONDOWN:
+		print("Button {0} was pressed.\n".format(msg['attrs'][0])
+	elif msg['message'] == upiwin.WM_HWBUTTONUP:
+		print("Button {0} was released.\n".format(msg['attrs'][0])
+		bn = msg['attrs'][0]
+		if bn == 1:
+			print("Backlight ON.\n")
+			upiwin.set_backlight(True)
+		elif bn == 2:
+			print("Backlight OFF.\n")
+			upiwin.set_backlight(True)
+		elif bn == 4:
+			print("Quitting the application.\n")
+			upiwin.post_quit_message(0)
+	elif msg['message'] == upiwin.WM_TOUCHDOWN:
+		log_touch('DOWN', msg['attrs'][0], msg['attrs'][1])
+	elif msg['message'] == upiwin.WM_TOUCHMOVE:
+		log_touch('MOVE', msg['attrs'][0], msg['attrs'][1])
+	elif msg['message'] == upiwin.WM_TOUCHUP:
+		log_touch('UP', msg['attrs'][0], msg['attrs'][1])

src/Makefile

@@ -2,7 +2,8 @@ BUILDUTILS=../buildutils
 RESOURCES=../resources
 SPLASHSCREEN=splash-vmwcblk.png
 
-OBJS=main.o sysinput.o ep_init.o ep_upiwin.o ep_backlight.o ep_upiwin_tmp.o ep_util.o fbinit.o rect.o fontengine.o fbprimitive.o \
+OBJS=main.o sysinput.o ep_init.o ep_upiwin.o ep_backlight.o ep_msg.o ep_upiwin_tmp.o ep_util.o \
+     fbinit.o rect.o fontengine.o fbprimitive.o \
      log.o gpio.o msg_queue.o time_func.o config.o splash.o
 LIBS=-lpython3.7m -lcrypt -lfreetype -lbcm2835 -lpthread -ldl -lutil -lm
 CFLAGS=-I/usr/include/python3.7m -I/usr/include/freetype2 -I/usr/include/libpng16 \

src/ep_msg.c

@@ -0,0 +1,68 @@
+#define PY_SSIZE_T_CLEAN
+#include <Python.h>
+#include "scode.h"
+#include "msg_queue.h"
+#include "sysinput.h"
+#include "ep_upiwin.h"
+#include "ep_init.h"
+
+static HRESULT convert_msg(PyDictObject *target, PMSG source)
+{
+  PyObject *attr;
+  
+  PyDict_Clear(target);
+  attr = PyLong_FromUnsignedLong(source->target);
+  if (!attr)
+    return E_FAIL;
+  if (PyDict_SetItemString(target, "target", attr))
+	return E_FAIL;
+  attr = PyLong_FromUnsignedLong(source->message);
+  if (!attr)
+    return E_FAIL;
+  if (PyDict_SetItemString(target, "message", attr))
+	return E_FAIL;
+  attr = Py_BuildValue("[k,k]", source->attrs[0], source->attrs[1]);
+  if (!attr)
+    return E_FAIL;
+  if (PyDict_SetItemString(target, "attrs", attr))
+	return E_FAIL;
+  attr = PyLong_FromUnsignedLongLong(source->timestamp);
+  if (!attr)
+    return E_FAIL;
+  if (PyDict_SetItemString(target, "timestamp", attr))
+	return E_FAIL;
+  return S_OK;
+}
+
+PyObject *Epython_get_message(PyObject *self, PyObject *args)
+{
+  PyDictObject *out;
+  MSG msg;
+  
+  if (!PyArg_ParseTuple(args, "O!", &PyDict_Type, &out))
+    return NULL;
+  
+  /* release the GIL to allow us to block waiting for input if necessary */
+  Py_BEGIN_ALLOW_THREADS
+  while (!Mq_peek(Sys_Queue, &msg, PEEK_REMOVE))
+    Sys_wait_for_input();
+  Py_END_ALLOW_THREADS
+  
+  if (FAILED(convert_msg(out, &msg)))
+  {
+    PyErr_SetString(PyExc_RuntimeError, "could not convert received message");
+	return NULL;
+  }
+  return PyBool_FromLong(msg.message != WM_QUIT);
+}
+
+PyObject *Epython_post_quit_message(PyObject *self, PyObject *args)
+{
+  INT32 exitcode;
+  
+  if (!PyArg_ParseTuple(args, "i", &exitcode))
+    return NULL;
+  Sys_Exit_Code = exitcode;
+  Mq_post1(Sys_Queue, NULL, WM_QUIT, exitcode);
+  Py_RETURN_NONE;
+}

src/ep_upiwin.c

@@ -1,9 +1,11 @@
 #define PY_SSIZE_T_CLEAN
 #include <Python.h>
 #include "scode.h"
-#include "ep_init.h"
+#include "msg.h"
 #include "gpio.h"
+#include "ep_init.h"
 #include "ep_upiwin.h"
+#include "ep_util.h"
 
 static PyMethodDef UPIWINMethods[] = {
   /* Backlight control functions */
@@ -15,6 +17,11 @@ static PyMethodDef UPIWINMethods[] = {
    "Returns the current intensity level of the backlight."},
   {"set_backlight_level", Epython_set_backlight_level, METH_VARARGS,
    "Sets the current intensity level of the backlight. Returns a SCODE."},
+  /* Message functions */
+  {"get_message", Epython_get_message, METH_VARARGS,
+   "Retrieves a message from the message queue, blocking if necessary."},
+  {"post_quit_message", Epython_post_quit_message, METH_VARARGS,
+   "Posts a WM_QUIT message to the message queue, with an exit code."},
   {NULL, NULL, 0, NULL}
 };
 
@@ -30,6 +37,17 @@ static PyModuleDef DefUPIWIN = {
   NULL                       /* no free function */
 };
 
+BEGIN_CONSTANT_TABLE(UPIWINConstants)
+  /* Message constants */
+  CONSTANT_INT_MACRO(WM_NULL)
+  CONSTANT_INT_MACRO(WM_QUIT)
+  CONSTANT_INT_MACRO(WM_HWBUTTONDOWN)
+  CONSTANT_INT_MACRO(WM_HWBUTTONUP)
+  CONSTANT_INT_MACRO(WM_TOUCHDOWN)
+  CONSTANT_INT_MACRO(WM_TOUCHMOVE)
+  CONSTANT_INT_MACRO(WM_TOUCHUP)
+END_CONSTANT_TABLE
+
 PyObject *Epython_init_upiwin_module(void)
 {
   PyObject *module;
@@ -38,6 +56,12 @@ PyObject *Epython_init_upiwin_module(void)
   module = PyModule_Create(&DefUPIWIN);
   if (!module)
     return NULL;
+	
+  if (FAILED(Epython_register_constants(module, UPIWINConstants)))
+  {
+	Py_DECREF(module);
+	return NULL;
+  }
 
   /* set up the module state */
   pstate = (PUPIWIN_STATE)PyModule_GetState(module);

src/ep_upiwin.h

@@ -11,9 +11,16 @@ typedef struct tagUPIWIN_STATE {
 } UPIWIN_STATE, *PUPIWIN_STATE;
 
 /* method definitions go here */
+
+/* ep_backlight.c */
 extern PyObject *Epython_get_backlight(PyObject *self, PyObject *args);
 extern PyObject *Epython_set_backlight(PyObject *self, PyObject *args);
 extern PyObject *Epython_get_backlight_level(PyObject *self, PyObject *args);
 extern PyObject *Epython_set_backlight_level(PyObject *self, PyObject *args);
 
+/* ep_msg.c */
+extern PyObject *Epython_get_message(PyObject *self, PyObject *args);
+extern PyObject *Epython_post_quit_message(PyObject *self, PyObject *args);
+
+
 #endif /* __EP_UPIWIN_H_INCLUDED */

src/main.c

@@ -12,11 +12,6 @@
 #include "ep_init.h"
 #include "sysinput.h"
 
-static void log_touch(const char *event, UINT_PTR x, UINT_PTR y)
-{
-  Log(LINFO, "Touch %s at (%u, %u)", event, x, y);
-}
-
 int main(int argc, char *argv[])
 {
   HRESULT hr;
@@ -47,54 +42,6 @@ int main(int argc, char *argv[])
   if (FAILED(Epython_run()))
     return EXIT_FAILURE;
  
-  Log(LINFO, "Script returned and event loop ready.");
+  Log(LINFO, "Script returned with exit code %d", Sys_Exit_Code);
-
+  return Sys_Exit_Code;
-  while (running)
-  {
-    if (Mq_peek(Sys_Queue, &msg, PEEK_REMOVE))
-    {
-      switch (msg.message)
-      {
-	case WM_HWBUTTONDOWN:
-	  Log(LINFO, "Button %d was pressed.", (int)(msg.attrs[0]));
-	  break;
-
-	case WM_HWBUTTONUP:
-	  Log(LINFO, "Button %d was released.", (int)(msg.attrs[0]));
-	  if (msg.attrs[0] == 1)
-	  {
-	    Log(LINFO, "Backlight ON.");
-	    Gpio_set_backlight(GSB_BACKLIGHT_MAX);
-	  }
-	  if (msg.attrs[0] == 2)
-	  {
-	    Log(LINFO, "Backlight OFF.");
-	    Gpio_set_backlight(0);
-	  }
-	  if (msg.attrs[0] == 4)
-	  {
-	    Log(LINFO, "Quitting the message loop.");
-	    running = 0;
-	  }
-	  break;
-
-	case WM_TOUCHDOWN:
-	  log_touch("DOWN", msg.attrs[0], msg.attrs[1]);
-	  break;
-	  
-	case WM_TOUCHMOVE:
-	  log_touch("MOVE", msg.attrs[0], msg.attrs[1]);
-	  break;
-	  
-	case WM_TOUCHUP:
-	  log_touch("UP", msg.attrs[0], msg.attrs[1]);
-	  break;
-	  
-	default:
-	  break;
-      }
-    }
-  }
-  
-  return EXIT_SUCCESS;
 }

src/msg.h

@@ -13,6 +13,7 @@ typedef struct tagMSG {
 } MSG, *PMSG;
 
 #define WM_NULL           0x0000
+#define WM_QUIT           0x0001
 
 #define WM_HWBUTTONDOWN   0x0020
 #define WM_HWBUTTONUP     0x0021

src/sysinput.c

@@ -16,6 +16,7 @@
 #define INPUT_EVENT_BATCH 16   /* number of events to retrieve from touchscreen at once */
 
 PMSG_QUEUE Sys_Queue = NULL;   /* system message queue */
+INT32 Sys_Exit_Code = -1;      /* system exit code, set on WM_QUIT */
 static int ts_fd = 0;          /* file descriptor for touchscreen */
 
 static pthread_t ithread;                    /* input thread handle */

src/sysinput.h

@@ -5,6 +5,7 @@
 #include "msg_queue.h"
 
 extern PMSG_QUEUE Sys_Queue;
+extern INT32 Sys_Exit_Code;
 
 extern HRESULT Sys_enable_input(void);
 extern void Sys_wait_for_input(void);