added xrick game

original xrick code by 'BigOrno' at:
http://www.bigorno.net/xrick/

Rockbox port, plus bugfixes at:
https://github.com/pierluigi-vicinanza/xrick

Further changes:

 * Additonal fixes from g#3026
 * Port to modern plugin API
 * Add Pluginlib keymap fallback
 * Support all >1bpp screens
 * Fix build warnings in miniz
 * Better error message when resources are missing

Change-Id: Id83928bc2539901b0221692f65cbca41389c58e7

apps/plugins/xrick/system/sysmem_rockbox.c

@@ -0,0 +1,156 @@
+ /***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Port of xrick, a Rick Dangerous clone, to Rockbox.
+ * See http://www.bigorno.net/xrick/
+ *
+ * Copyright (C) 2008-2014 Pierluigi Vicinanza
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#include "xrick/system/system.h"
+
+#include "xrick/debug.h"
+
+#include "plugin.h"
+
+/*
+ * Local variables
+ */
+enum
+{
+    ALIGNMENT = sizeof(void*)  /* this is more of an educated guess; might want to adjust for your specific architecture */
+};
+static U8 * stackBuffer;
+static U8 * stackTop;
+static size_t stackSize;
+static size_t stackMaxSize;
+static bool isMemoryInitialised = false;
+IFDEBUG_MEMORY( static size_t maxUsedMemory = 0; );
+
+/*
+ * Initialise memory stack
+ */
+bool sysmem_init(void)
+{
+    if (isMemoryInitialised)
+    {
+        return true;
+    }
+
+    if (rb->audio_status())
+    {
+        /* Playback must be stopped the entire time the sound buffer is used.*/
+        rb->audio_stop();
+    }
+
+    stackBuffer = rb->plugin_get_audio_buffer(&stackMaxSize);
+    stackTop = stackBuffer;
+    stackSize = 0;
+    isMemoryInitialised = true;
+    return true;
+}
+
+/*
+ * Cleanup memory stack
+ */
+void sysmem_shutdown(void)
+{
+    if (!isMemoryInitialised)
+    {
+        return;
+    }
+
+    if (stackTop != stackBuffer || stackSize != 0)
+    {
+        sys_error("(memory) improper deallocation detected");
+    }
+
+    IFDEBUG_MEMORY(
+        sys_printf("xrick/memory: max memory usage was %u bytes\n", maxUsedMemory);
+    );
+
+    isMemoryInitialised = false;
+}
+
+/*
+ * Allocate a memory-aligned block on top of the memory stack
+ */
+void *sysmem_push(size_t size)
+{
+    uintptr_t alignedPtr;
+    size_t * allocatedSizePtr;
+
+    size_t neededSize = sizeof(size_t) + size + (ALIGNMENT - 1);
+    if (stackSize + neededSize > stackMaxSize)
+    {
+        sys_error("(memory) tried to allocate a block when memory full");
+        return NULL;
+    }
+
+    alignedPtr = (((uintptr_t)stackTop) + sizeof(size_t) + ALIGNMENT) & ~((uintptr_t)(ALIGNMENT - 1));
+
+    allocatedSizePtr = (size_t *)(alignedPtr);
+    allocatedSizePtr[-1] = neededSize;
+
+    stackTop += neededSize;
+    stackSize += neededSize;
+
+    IFDEBUG_MEMORY(
+        sys_printf("xrick/memory: allocated %u bytes\n", neededSize);
+        if (stackSize > maxUsedMemory) maxUsedMemory = stackSize;
+    );
+
+    return (void *)alignedPtr;
+}
+
+/*
+ * Release block from the top of the memory stack
+ */
+void sysmem_pop(void * alignedPtr)
+{
+    size_t allocatedSize;
+
+    if (!alignedPtr)
+    {
+        return;
+    }
+
+    if (stackSize == 0)
+    {
+        sys_error("(memory) tried to release a block when memory empty");
+        return;
+    }
+
+    allocatedSize = ((size_t *)(alignedPtr))[-1];
+    stackTop -= allocatedSize;
+    stackSize -= allocatedSize;
+
+    IFDEBUG_MEMORY(
+        if ((uintptr_t)alignedPtr != ((((uintptr_t)stackTop) + sizeof(size_t) + ALIGNMENT) & ~((uintptr_t)(ALIGNMENT - 1))))
+        {
+            sys_error("(memory) tried to release a wrong block");
+            return;
+        }
+    );
+
+    IFDEBUG_MEMORY(
+        sys_printf("xrick/memory: released %u bytes\n", allocatedSize);
+    );
+}
+
+/* eof */