spice-common/common/canvas_utils.c

/* -*- Mode: C; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
   Copyright (C) 2009 Red Hat, Inc.

   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, see <http://www.gnu.org/licenses/>.
*/
#include <config.h>

#include "canvas_utils.h"
#include "mem.h"

typedef struct PixmanData {
    uint8_t *data;
    pixman_format_code_t format;
} PixmanData;

static void release_data(SPICE_GNUC_UNUSED pixman_image_t *image,
                         void *release_data)
{
    PixmanData *data = (PixmanData *)release_data;

    free(data->data);

    free(data);
}

static PixmanData *
pixman_image_add_data(pixman_image_t *image)
{
    PixmanData *data;

    data = (PixmanData *)pixman_image_get_destroy_data(image);
    if (data == NULL) {
        data = (PixmanData *)calloc(1, sizeof(PixmanData));
        if (data == NULL) {
            spice_error("out of memory");
        }
        pixman_image_set_destroy_function(image,
                                          release_data,
                                          data);
    }

    return data;
}

void
spice_pixman_image_set_format(pixman_image_t *image,
                              pixman_format_code_t format)
{
    PixmanData *data;

    data = pixman_image_add_data(image);
    data->format = format;
}


int spice_pixman_image_get_format(pixman_image_t *image, pixman_format_code_t *format)
{
    PixmanData *data;

    spice_return_val_if_fail(format != NULL, 0);

    data = (PixmanData *)pixman_image_get_destroy_data(image);
    if (data != NULL && data->format != 0) {
        *format = data->format;
        return 1;
    }

    spice_warn_if_reached();
    return 0;
}

pixman_image_t *surface_create_stride(pixman_format_code_t format, int width, int height,
                                      int stride)
{
    uint8_t *data;
    uint8_t *stride_data;
    pixman_image_t *surface;
    PixmanData *pixman_data;

    data = (uint8_t *)spice_malloc_n(abs(stride), height);
    if (stride < 0) {
        stride_data = data + (-stride) * (height - 1);
    } else {
        stride_data = data;
    }

    surface = pixman_image_create_bits(format, width, height, (uint32_t *)stride_data, stride);

    if (surface == NULL) {
        free(data);
        data = NULL;
        spice_error("create surface failed, out of memory");
    }

    pixman_data = pixman_image_add_data(surface);
    pixman_data->data = data;
    pixman_data->format = format;

    return surface;
}

pixman_image_t * surface_create(pixman_format_code_t format, int width, int height, int top_down)
{
    if (top_down) {
        pixman_image_t *surface;
        PixmanData *data;

        surface = pixman_image_create_bits(format, width, height, NULL, 0);
        data = pixman_image_add_data(surface);
        data->format = format;
        return surface;
    } else {
        // NOTE: we assume here that the lz decoders always decode to RGB32.
        int stride = 0;
        switch (format) {
        case PIXMAN_a8r8g8b8:
        case PIXMAN_x8r8g8b8:
#ifdef WORDS_BIGENDIAN
        case PIXMAN_b8g8r8a8:
        case PIXMAN_b8g8r8x8:
#endif
            stride = width * 4;
            break;
        case PIXMAN_r8g8b8:
#ifdef WORDS_BIGENDIAN
        case PIXMAN_b8g8r8:
#endif
            // NOTE: LZ4 also decodes to RGB24
            stride = SPICE_ALIGN(width * 3, 4);
            break;
        case PIXMAN_x1r5g5b5:
        case PIXMAN_r5g6b5:
            stride = SPICE_ALIGN(width * 2, 4);
            break;
        case PIXMAN_a8:
            stride = SPICE_ALIGN(width, 4);
            break;
        case PIXMAN_a1:
            stride = SPICE_ALIGN(width, 32) / 8;
            break;
        default:
            spice_error("invalid format");
        }
        stride = -stride;
        return surface_create_stride(format, width, height, stride);
    }
}

pixman_image_t *alloc_lz_image_surface(LzDecodeUsrData *canvas_data,
                                       pixman_format_code_t pixman_format, int width,
                                       int height, int gross_pixels, int top_down)
{
    int stride;
    pixman_image_t *surface = NULL;

    stride = (gross_pixels / height) * (PIXMAN_FORMAT_BPP (pixman_format) / 8);

    /* pixman requires strides to be 4-byte aligned */
    stride = SPICE_ALIGN(stride, 4);

    if (!top_down) {
        stride = -stride;
    }

    surface = surface_create_stride(pixman_format, width, height, stride);
    canvas_data->out_surface = surface;
    return surface;
}