libbb/fgets_str.c

/* vi: set sw=4 ts=4: */
/*
 * Utility routines.
 *
 * Copyright (C) many different people.
 * If you wrote this, please acknowledge your work.
 *
 * 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 2 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, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */


#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "libbb.h"

/* Read up to (and including) TERMINATING_STRING from FILE and return it.
 * Return NULL on EOF.  */

char *fgets_str(FILE *file, const char *terminating_string)
{
	char *linebuf = NULL;
	const int term_length = strlen(terminating_string);
	int end_string_offset;
	int linebufsz = 0;
	int idx = 0;
	int ch;

	while (1) {
		ch = fgetc(file);
		if (ch == EOF) {
			free(linebuf);
			return NULL;
		}

		/* grow the line buffer as necessary */
		while (idx > linebufsz - 2) {
			linebuf = xrealloc(linebuf, linebufsz += 1000);
		}

		linebuf[idx] = ch;
		idx++;

		/* Check for terminating string */
		end_string_offset = idx - term_length;
		if ((end_string_offset > 0) && (memcmp(&linebuf[end_string_offset], terminating_string, term_length) == 0)) {
			idx -= term_length;
			break;
		}
	}
	linebuf[idx] = '\0';
	return(linebuf);
}