source: mainline/uspace/lib/gfxfont/src/font.c@ c78a03d

/*
 * Copyright (c) 2020 Jiri Svoboda
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup libgfxfont
 * @{
 */
/**
 * @file Font
 */

#include <adt/list.h>
#include <assert.h>
#include <errno.h>
#include <gfx/font.h>
#include <gfx/glyph.h>
#include <mem.h>
#include <stdlib.h>
#include "../private/font.h"
#include "../private/glyph.h"

/** Initialize font metrics structure.
 *
 * Font metrics structure must always be initialized using this function
 * first.
 *
 * @param metrics Font metrics structure
 */
void gfx_font_metrics_init(gfx_font_metrics_t *metrics)
{
        memset(metrics, 0, sizeof(gfx_font_metrics_t));
}

/** Create font in graphics context.
 *
 * @param gc Graphic context
 * @param metrics Font metrics
 * @param rfont Place to store pointer to new font
 *
 * @return EOK on success, EINVAL if parameters are invald,
 *         ENOMEM if insufficient resources, EIO if graphic device connection
 *         was lost
 */
errno_t gfx_font_create(gfx_context_t *gc, gfx_font_metrics_t *metrics,
    gfx_font_t **rfont)
{
        gfx_font_t *font;
        errno_t rc;

        font = calloc(1, sizeof(gfx_font_t));
        if (font == NULL)
                return ENOMEM;

        font->gc = gc;

        rc = gfx_font_set_metrics(font, metrics);
        if (rc != EOK) {
                assert(rc == EINVAL);
                free(font);
                return rc;
        }

        font->metrics = *metrics;
        list_initialize(&font->glyphs);
        *rfont = font;
        return EOK;
}

/** Destroy font.
 *
 * @param font Font
 */
void gfx_font_destroy(gfx_font_t *font)
{
        gfx_glyph_t *glyph;

        glyph = gfx_font_first_glyph(font);
        while (glyph != NULL) {
                gfx_glyph_destroy(glyph);
                glyph = gfx_font_first_glyph(font);
        }

        free(font);
}

/** Get font metrics.
 *
 * @param font Font
 * @param metrics Place to store metrics
 */
void gfx_font_get_metrics(gfx_font_t *font, gfx_font_metrics_t *metrics)
{
        *metrics = font->metrics;
}

/** Set font metrics.
 *
 * @param font Font
 * @param metrics Place to store metrics
 * @return EOK on success, EINVAL if supplied metrics are invalid
 */
errno_t gfx_font_set_metrics(gfx_font_t *font, gfx_font_metrics_t *metrics)
{
        font->metrics = *metrics;
        return EOK;
}

/** Get first glyph in font.
 *
 * @param font Font
 * @return First glyph or @c NULL if there are none
 */
gfx_glyph_t *gfx_font_first_glyph(gfx_font_t *font)
{
        link_t *link;

        link = list_first(&font->glyphs);
        if (link == NULL)
                return NULL;

        return list_get_instance(link, gfx_glyph_t, lglyphs);
}

/** Get next glyph in font.
 *
 * @param cur Current glyph
 * @return Next glyph in font or @c NULL if @a cur was the last one
 */
gfx_glyph_t *gfx_font_next_glyph(gfx_glyph_t *cur)
{
        link_t *link;

        link = list_next(&cur->lglyphs, &cur->font->glyphs);
        if (link == NULL)
                return NULL;

        return list_get_instance(link, gfx_glyph_t, lglyphs);
}

/** Search for glyph that should be set for the beginning of a string.
 *
 * @param font Font
 * @param str String whose beginning we would like to set
 * @param rglyph Place to store glyph that should be set
 * @param rsize Place to store number of bytes to advance in the string
 * @return EOK on success, ENOENT if no matching glyph was found
 */
int gfx_font_search_glyph(gfx_font_t *font, const char *str,
    gfx_glyph_t **rglyph, size_t *rsize)
{
        gfx_glyph_t *glyph;
        size_t msize;

        glyph = gfx_font_first_glyph(font);
        while (glyph != NULL) {
                if (gfx_glyph_matches(glyph, str, &msize)) {
                        *rglyph = glyph;
                        *rsize = msize;
                        return EOK;
                }

                glyph = gfx_font_next_glyph(glyph);
        }

        return ENOENT;
}

/** @}
 */