/*  Implementation of a ring buffer for reports
 *
 * Copyright 2015 CodeWeavers, Aric Stewart
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */

#include "config.h"
#include <stdarg.h>
#define NONAMELESSUNION
#include "hid.h"

#include "wine/debug.h"

WINE_DEFAULT_DEBUG_CHANNEL(hid);

#define BASE_BUFFER_SIZE 32

struct ReportRingBuffer
{
    UINT start, end, size;

    int *pointers;
    UINT pointer_alloc;
    UINT buffer_size;

    CRITICAL_SECTION lock;

    BYTE *buffer;
};

struct ReportRingBuffer* RingBuffer_Create(UINT buffer_size)
{
    struct ReportRingBuffer *ring;
    TRACE("Create Ring Buffer with buffer size %i\n",buffer_size);
    ring = HeapAlloc(GetProcessHeap(), 0, sizeof(*ring));
    if (!ring)
        return NULL;
    ring->start = ring->end = 0;
    ring->size = BASE_BUFFER_SIZE;
    ring->buffer_size = buffer_size;
    ring->pointer_alloc = 2;
    ring->pointers = HeapAlloc(GetProcessHeap(), 0, sizeof(int) * ring->pointer_alloc);
    if (!ring->pointers)
    {
        HeapFree(GetProcessHeap(), 0, ring);
        return NULL;
    }
    memset(ring->pointers, 0xff, sizeof(int) * ring->pointer_alloc);
    ring->buffer = HeapAlloc(GetProcessHeap(), 0, buffer_size * ring->size);
    if (!ring->buffer)
    {
        HeapFree(GetProcessHeap(), 0, ring->pointers);
        HeapFree(GetProcessHeap(), 0, ring);
        return NULL;
    }
    InitializeCriticalSection(&ring->lock);
    ring->lock.DebugInfo->Spare[0] = (DWORD_PTR)(__FILE__ ": RingBuffer.lock");
    return ring;
}

void RingBuffer_Destroy(struct ReportRingBuffer *ring)
{
    HeapFree(GetProcessHeap(), 0, ring->buffer);
    HeapFree(GetProcessHeap(), 0, ring->pointers);
    ring->lock.DebugInfo->Spare[0] = 0;
    DeleteCriticalSection(&ring->lock);
    HeapFree(GetProcessHeap(), 0, ring);
}