util.c

/*
 * ISC License
 *
 * Copyright (c) 2022, Tommi Leino <namhas@gmail.com>
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "util.h"

#include <stdlib.h>
#include <assert.h>
#include <err.h>

/*
 * Example:
 *   static struct str;
 *
 *   str_add(&str, 'a');
 *
 * Use '\0' to reset the str without needing to reallocate.
 */
void
str_add(struct str *str, char c)
{
	assert(str != NULL);

	if (c == '\0') {
		str->len = 0;
		if (str->s != NULL)
			str->s[str->len] = '\0';
		return;
	}

#define STR_CHUNK 64
	if (str->len+1 >= str->alloc) {
		str->alloc += STR_CHUNK;
		str->s = realloc(str->s, str->alloc);
		if (str->s == NULL)
			err(1, "realloc str");
	}

	str->s[str->len++] = c;
	str->s[str->len] = '\0';
}