Add support for the Nokia N-Gage (#5597)

* Add initial support for the Nokia N-Gage

* N-Gage: disable clipping for the time being, issue needs to be resolved later

* Move va_copy definition to SDL_internal.h

* Move stdlib.h include to SDL_config_ngage.h, much cleaner this way

* Remove redundant include, add HAVE_STDLIB_H

* Revert "N-Gage: disable clipping for the time being, issue needs to be resolved later"

This reverts commit 4f5f0fc36c.

* N-Gage: fix clipping issue by providing proper math functions

src/thread/ngage/SDL_sysmutex.cpp

@@ -0,0 +1,107 @@
+/*
+  Simple DirectMedia Layer
+  Copyright (C) 1997-2022 Sam Lantinga <slouken@libsdl.org>
+
+  This software is provided 'as-is', without any express or implied
+  warranty.  In no event will the authors be held liable for any damages
+  arising from the use of this software.
+
+  Permission is granted to anyone to use this software for any purpose,
+  including commercial applications, and to alter it and redistribute it
+  freely, subject to the following restrictions:
+
+  1. The origin of this software must not be misrepresented; you must not
+     claim that you wrote the original software. If you use this software
+     in a product, an acknowledgment in the product documentation would be
+     appreciated but is not required.
+  2. Altered source versions must be plainly marked as such, and must not be
+     misrepresented as being the original software.
+  3. This notice may not be removed or altered from any source distribution.
+*/
+#include "../../SDL_internal.h"
+
+/* An implementation of mutexes using semaphores */
+
+#include <e32std.h>
+
+#include "SDL_thread.h"
+#include "SDL_systhread_c.h"
+
+struct SDL_mutex
+{
+    TInt handle;
+};
+
+extern TInt CreateUnique(TInt (*aFunc)(const TDesC& aName, TAny*, TAny*), TAny*, TAny*);
+
+static TInt NewMutex(const TDesC& aName, TAny* aPtr1, TAny*)
+{
+    return ((RMutex*)aPtr1)->CreateGlobal(aName);
+}
+
+/* Create a mutex */
+SDL_mutex *
+SDL_CreateMutex(void)
+{
+    RMutex rmutex;
+
+    TInt status = CreateUnique(NewMutex, &rmutex, NULL);
+    if(status != KErrNone)
+    {
+        SDL_SetError("Couldn't create mutex.");
+    }
+    SDL_mutex* mutex = new /*(ELeave)*/ SDL_mutex;
+    mutex->handle = rmutex.Handle();
+    return(mutex);
+}
+
+/* Free the mutex */
+void
+SDL_DestroyMutex(SDL_mutex * mutex)
+{
+    if (mutex)
+    {
+        RMutex rmutex;
+        rmutex.SetHandle(mutex->handle);
+        rmutex.Signal();
+        rmutex.Close();
+        delete(mutex);
+        mutex = NULL;
+    }
+}
+
+/* Lock the mutex */
+int
+SDL_LockMutex(SDL_mutex * mutex)
+{
+    if (mutex == NULL)
+    {
+        SDL_SetError("Passed a NULL mutex.");
+        return -1;
+    }
+
+    RMutex rmutex;
+    rmutex.SetHandle(mutex->handle);
+    rmutex.Wait();
+
+    return(0);
+}
+
+/* Unlock the mutex */
+int
+SDL_mutexV(SDL_mutex * mutex)
+{
+    if ( mutex == NULL )
+    {
+        SDL_SetError("Passed a NULL mutex.");
+        return -1;
+    }
+
+    RMutex rmutex;
+    rmutex.SetHandle(mutex->handle);
+    rmutex.Signal();
+
+    return(0);
+}
+
+/* vi: set ts=4 sw=4 expandtab: */