/* string-util.c -  Extra or enhanced routines for null terminated strings.
 *
 * Copyright (c) 2012 Jani Nikula
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see http://www.gnu.org/licenses/ .
 *
 * Author: Jani Nikula <jani@nikula.org>
 */


#include "string-util.h"
#include "talloc.h"

char *
strtok_len (char *s, const char *delim, size_t *len)
{
    /* skip initial delims */
    s += strspn (s, delim);

    /* length of token */
    *len = strcspn (s, delim);

    return *len ? s : NULL;
}


size_t
strnspn (const char *str, size_t len,  const char *accept)
{
    size_t count;

    for (count = 0; count < len && str[count] != '\0'; count++) {
	if (strchr (accept, str[count]) == NULL)
	    break;
    }
    return count;
}

int
double_quote_str (void *ctx, const char *str,
		  char **buf, size_t *len)
{
    const char *in;
    char *out;
    size_t needed = 3;

    for (in = str; *in; in++)
	needed += (*in == '"') ? 2 : 1;

    if ((*buf == NULL) || (needed > *len)) {
	*len = 2 * needed;
	*buf = talloc_realloc (ctx, *buf, char, *len);
    }


    if (! *buf)
	return 1;

    out = *buf;

    *out++ = '"';
    in = str;
    while (*in) {
	if (*in == '"')
	    *out++ = '"';
	*out++ = *in++;
    }
    *out++ = '"';
    *out = '\0';

    return 0;
}