xref: /openbsd-src/usr.sbin/cron/misc.c (revision 39339e78fa3cf6f5639ec222befd248e06ea5b5c)

/*	$OpenBSD: misc.c,v 1.72 2022/05/21 01:21:29 deraadt Exp $	*/

/* Copyright 1988,1990,1993,1994 by Paul Vixie
 * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
 * Copyright (c) 1997,2000 by Internet Software Consortium, Inc.
 *
 * Permission to use, copy, modify, and 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 ISC DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC 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 <sys/types.h>
#include <sys/wait.h>

#include <bitstring.h>		/* for structs.h */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>		/* for structs.h */

#include "macros.h"
#include "structs.h"
#include "funcs.h"
#include "globals.h"

int LineNumber;

/* get_char(file) : like getc() but increment LineNumber on newlines
 */
int
get_char(FILE *file)
{
	int ch;

	ch = getc(file);
	if (ch == '\n')
		Set_LineNum(LineNumber + 1)
	return (ch);
}

/* unget_char(ch, file) : like ungetc but do LineNumber processing
 */
void
unget_char(int ch, FILE *file)
{
	ungetc(ch, file);
	if (ch == '\n')
		Set_LineNum(LineNumber - 1)
}

/* get_string(str, max, file, termstr) : like fgets() but
 *		(1) has terminator string which should include \n
 *		(2) will always leave room for the null
 *		(3) uses get_char() so LineNumber will be accurate
 *		(4) returns EOF or terminating character, whichever
 */
int
get_string(char *string, int size, FILE *file, char *terms)
{
	int ch;

	while ((ch = get_char(file)) != EOF && !strchr(terms, ch)) {
		if (size > 1) {
			*string++ = ch;
			size--;
		}
	}

	if (size > 0)
		*string = '\0';

	return (ch);
}

/* skip_comments(file) : read past comment (if any)
 */
void
skip_comments(FILE *file)
{
	int ch;

	while ((ch = get_char(file)) != EOF) {
		/* ch is now the first character of a line.
		 */

		while (ch == ' ' || ch == '\t')
			ch = get_char(file);

		if (ch == EOF)
			break;

		/* ch is now the first non-blank character of a line.
		 */

		if (ch != '\n' && ch != '#')
			break;

		/* ch must be a newline or comment as first non-blank
		 * character on a line.
		 */

		while (ch != '\n' && ch != EOF)
			ch = get_char(file);

		/* ch is now the newline of a line which we're going to
		 * ignore.
		 */
	}
	if (ch != EOF)
		unget_char(ch, file);
}

/* char *first_word(char *s, char *t)
 *	return pointer to first word
 * parameters:
 *	s - string we want the first word of
 *	t - terminators, implicitly including \0
 * warnings:
 *	(1) this routine is fairly slow
 *	(2) it returns a pointer to static storage
 */
char *
first_word(char *s, char *t)
{
	static char retbuf[2][MAX_TEMPSTR + 1];	/* sure wish C had GC */
	static int retsel = 0;
	char *rb, *rp;

	/* select a return buffer */
	retsel = 1-retsel;
	rb = &retbuf[retsel][0];
	rp = rb;

	/* skip any leading terminators */
	while (*s && (NULL != strchr(t, *s))) {
		s++;
	}

	/* copy until next terminator or full buffer */
	while (*s && (NULL == strchr(t, *s)) && (rp < &rb[MAX_TEMPSTR])) {
		*rp++ = *s++;
	}

	/* finish the return-string and return it */
	*rp = '\0';
	return (rb);
}