[host] windows: move the service log to the temp directory

Often this log is provided instead of the actual host log, as this
log is largely useless for debugging this moves it to the temp
directory out of view of the user.

host/platform/Windows/src/platform.c

@@ -58,6 +58,7 @@ struct AppState
 
   char           executable[MAX_PATH + 1];
   char           systemLogDir[MAX_PATH];
+  char           systemTempDir[MAX_PATH];
   char         * osVersion;
   HWND           messageWnd;
   UINT           shellHookMsg;
@@ -299,6 +300,11 @@ static BOOL WINAPI CtrlHandler(DWORD dwCtrlType)
   return FALSE;
 }
 
+const char * getSystemTempDirectory(void)
+{
+  return app.systemTempDir;
+}
+
 const char *getSystemLogDirectory(void)
 {
   return app.systemLogDir;
@@ -340,6 +346,7 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 
   GetModuleFileName(NULL, app.executable, sizeof(app.executable));
   populateSystemLogDirectory();
+  GetTempPathA(sizeof(app.systemTempDir), app.systemTempDir);
 
   if (HandleService(app.argc, app.argv))
     return LG_HOST_EXIT_FAILED;

host/platform/Windows/src/platform.h

@@ -51,5 +51,6 @@ struct MSG_CALL_FUNCTION
 };
 
 bool windowsSetupAPI(void);
-const char *getSystemLogDirectory(void);
+const char * getSystemTempDirectory(void);
+const char * getSystemLogDirectory(void);
 LRESULT sendAppMessage(UINT Msg, WPARAM wParam, LPARAM lParam);

host/platform/Windows/src/service.c

@@ -78,7 +78,13 @@ void doLogReal(const char * fmt, ...)
 static void setupLogging(void)
 {
   char logFilePath[MAX_PATH];
-  if (!PathCombineA(logFilePath, getSystemLogDirectory(), LOG_NAME))
+
+  // remove the old service log file if it exists
+  if (PathCombineA(logFilePath, getSystemLogDirectory(), LOG_NAME))
+    unlink(logFilePath);
+
+  // open the service file in the temp directory as we usually do not need it
+  if (!PathCombineA(logFilePath, getSystemTempDirectory(), LOG_NAME))
     strcpy(logFilePath, LOG_NAME);
   service.logFile = fopen(logFilePath, "a+");
   setbuf(service.logFile, NULL);