Archipelago » qemu

/*

 * QEMU VNC display driver: palette hash table

 *

 * From libvncserver/libvncserver/tight.c

 * Copyright (C) 2000, 2001 Const Kaplinsky.  All Rights Reserved.

 * Copyright (C) 1999 AT&T Laboratories Cambridge.  All Rights Reserved.

 *

 * Copyright (C) 2010 Corentin Chary <corentin.chary@gmail.com>

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#include "vnc-palette.h"

static VncPaletteEntry *palette_find(const VncPalette *palette,

                                     uint32_t color, unsigned int hash)

{

    VncPaletteEntry *entry;

    QLIST_FOREACH(entry, &palette->table[hash], next) {

        if (entry->color == color) {

            return entry;

        }

    }

    return NULL;

}

static unsigned int palette_hash(uint32_t rgb, int bpp)

{

    if (bpp == 16) {

        return ((unsigned int)(((rgb >> 8) + rgb) & 0xFF));

    } else {

        return ((unsigned int)(((rgb >> 16) + (rgb >> 8)) & 0xFF));

    }

}

VncPalette *palette_new(size_t max, int bpp)

{

    VncPalette *palette;

    palette = qemu_mallocz(sizeof(*palette));

    palette_init(palette, max, bpp);

    return palette;

}

void palette_init(VncPalette *palette, size_t max, int bpp)

{

    memset(palette, 0, sizeof (*palette));

    palette->max = max;

    palette->bpp = bpp;

}

void palette_destroy(VncPalette *palette)

{

    if (palette == NULL) {

        qemu_free(palette);

    }

}

int palette_put(VncPalette *palette, uint32_t color)

{

    unsigned int hash;

    unsigned int idx = palette->size;

    VncPaletteEntry *entry;

    hash = palette_hash(color, palette->bpp) % VNC_PALETTE_HASH_SIZE;

    entry = palette_find(palette, color, hash);

    if (!entry && palette->size >= palette->max) {

        return 0;

    }

    if (!entry) {

        VncPaletteEntry *entry;

        entry = &palette->pool[palette->size];

        entry->color = color;

        entry->idx = idx;

        QLIST_INSERT_HEAD(&palette->table[hash], entry, next);

        palette->size++;

    }

    return palette->size;

}

int palette_idx(const VncPalette *palette, uint32_t color)

{

    VncPaletteEntry *entry;

    unsigned int hash;

    hash = palette_hash(color, palette->bpp) % VNC_PALETTE_HASH_SIZE;

    entry = palette_find(palette, color, hash);

    return (entry == NULL ? -1 : entry->idx);

}

size_t palette_size(const VncPalette *palette)

{

    return palette->size;

}

void palette_iter(const VncPalette *palette,

                  void (*iter)(int idx, uint32_t color, void *opaque),

                  void *opaque)

{

    int i;

    VncPaletteEntry *entry;

    for (i = 0; i < VNC_PALETTE_HASH_SIZE; i++) {

        QLIST_FOREACH(entry, &palette->table[i], next) {

            iter(entry->idx, entry->color, opaque);

        }

    }

}