source: mainline/uspace/lib/ui/src/accel.c@ 0e2eee1

/*
 * Copyright (c) 2022 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 libui
 * @{
 */
/**
 * @file Accelerator processing
 */

#include <ctype.h>
#include <errno.h>
#include <stdlib.h>
#include <str.h>
#include <ui/accel.h>

/** Process text with accelerator markup.
 *
 * Parse text with tilde markup into a list of strings. @a *rbuf is set
 * to point to a newly allocated buffer containing consecutive null-terminated
 * strings.
 *
 * Each part between two '~' becomes one string. '~~' is translated into
 * a literal '~' character. @a *endptr is set to point to the first character
 * beyond the end of the list.
 *
 * @param str String with tilde markup
 * @param rbuf Place to store pointer to newly allocated buffer.
 * @param endptr Place to store end pointer (just after last character)
 * @return EOK on success or an error code
 */
errno_t ui_accel_process(const char *str, char **rbuf, char **endptr)
{
        const char *sp;
        char *dp;
        char *buf;

        buf = malloc(str_size(str) + 1);
        if (buf == NULL)
                return ENOMEM;

        /* Break down string into list of (non)highlighted parts */
        sp = str;
        dp = buf;
        while (*sp != '\0') {
                if (*sp == '~') {
                        if (sp[1] == '~') {
                                sp += 2;
                                *dp++ = '~';
                        } else {
                                ++sp;
                                *dp++ = '\0';
                        }
                } else {
                        *dp++ = *sp++;
                }
        }

        *dp++ = '\0';
        *rbuf = buf;
        *endptr = dp;

        return EOK;
}

/** Get accelerator character from marked-up string.
 *
 * @param str String with '~' accelerator markup
 *
 * @return Accelerator character (lowercase) or the null character if
 *         the menu has no accelerator.
 */
char32_t ui_accel_get(const char *str)
{
        const char *sp = str;
        size_t off;

        while (*sp != '\0') {
                if (*sp == '~') {
                        if (sp[1] == '~') {
                                ++sp;
                        } else {
                                /* Found the accelerator */
                                ++sp;
                                break;
                        }
                }

                ++sp;
        }

        if (*sp == '\0') {
                /* No accelerator */
                return '\0';
        }

        /* Decode accelerator character */
        off = 0;

        /*
         * NOTE: tolower is unlike to actually convert to lowercase
         * in case of non-ASCII characters
         */
        return tolower(str_decode(sp, &off, STR_NO_LIMIT));
}

/** @}
 */