Return to uniq.c CVS log

Up to [local] / src / usr.bin / uniq

uniq has a complicated initialization around getopt. beforehands, we
can tame "stdio rpath wpath cpath"; all three paths abilities are needed
for it to setup the right files (worst case spotted by sthen).  later
once the files are opened, the program is only looking at strings and
outputing via stdio functions, so we can tame "stdio".

/*	$OpenBSD: uniq.c,v 1.20 2015/10/03 02:18:20 deraadt Exp $	*/
/*	$NetBSD: uniq.c,v 1.7 1995/08/31 22:03:48 jtc Exp $	*/

/*
 * Copyright (c) 1989, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Case Larsen.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
 */

#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#define	MAXLINELEN	(8 * 1024)

int cflag, dflag, uflag;
int numchars, numfields, repeats;

FILE	*file(char *, char *);
void	 show(FILE *, char *);
char	*skip(char *);
void	 obsolete(char *[]);
__dead void	usage(void);

int
main(int argc, char *argv[])
{
	char *t1, *t2;
	FILE *ifp = NULL, *ofp = NULL;
	int ch;
	char *prevline, *thisline;

	if (tame("stdio rpath wpath cpath", NULL) == -1)
		err(1, "tame");

	obsolete(argv);
	while ((ch = getopt(argc, argv, "cdf:s:u")) != -1) {
		const char *errstr;

		switch (ch) {
		case 'c':
			cflag = 1;
			break;
		case 'd':
			dflag = 1;
			break;
		case 'f':
			numfields = (int)strtonum(optarg, 0, INT_MAX,
			    &errstr);
			if (errstr)
				errx(1, "field skip value is %s: %s",
				    errstr, optarg);
			break;
		case 's':
			numchars = (int)strtonum(optarg, 0, INT_MAX,
			    &errstr);
			if (errstr)
				errx(1,
				    "character skip value is %s: %s",
				    errstr, optarg);
			break;
		case 'u':
			uflag = 1;
			break;
		default:
			usage();
		}
	}

	argc -= optind;
	argv += optind;

	/* If neither -d nor -u are set, default is -d -u. */
	if (!dflag && !uflag)
		dflag = uflag = 1;

	switch(argc) {
	case 0:
		ifp = stdin;
		ofp = stdout;
		break;
	case 1:
		ifp = file(argv[0], "r");
		ofp = stdout;
		break;
	case 2:
		ifp = file(argv[0], "r");
		ofp = file(argv[1], "w");
		break;
	default:
		usage();
	}

	if (tame("stdio", NULL) != 0)
		err(1, "tame");

	prevline = malloc(MAXLINELEN);
	thisline = malloc(MAXLINELEN);
	if (prevline == NULL || thisline == NULL)
		err(1, "malloc");

	if (fgets(prevline, MAXLINELEN, ifp) == NULL)
		exit(0);

	while (fgets(thisline, MAXLINELEN, ifp)) {
		/* If requested get the chosen fields + character offsets. */
		if (numfields || numchars) {
			t1 = skip(thisline);
			t2 = skip(prevline);
		} else {
			t1 = thisline;
			t2 = prevline;
		}

		/* If different, print; set previous to new value. */
		if (strcmp(t1, t2)) {
			show(ofp, prevline);
			t1 = prevline;
			prevline = thisline;
			thisline = t1;
			repeats = 0;
		} else
			++repeats;
	}
	show(ofp, prevline);
	exit(0);
}

/*
 * show --
 *	Output a line depending on the flags and number of repetitions
 *	of the line.
 */
void
show(FILE *ofp, char *str)
{
	if ((dflag && repeats) || (uflag && !repeats)) {
		if (cflag)
			(void)fprintf(ofp, "%4d %s", repeats + 1, str);
		else
			(void)fprintf(ofp, "%s", str);
	}
}

char *
skip(char *str)
{
	int nchars, nfields;

	for (nfields = numfields; nfields && *str; nfields--) {
		while (isblank((unsigned char)*str))
			str++;
		while (*str && !isblank((unsigned char)*str))
			str++;
	}
	for (nchars = numchars; nchars-- && *str && *str != '\n'; ++str)
		;
	return (str);
}

FILE *
file(char *name, char *mode)
{
	FILE *fp;

	if (strcmp(name, "-") == 0)
		return(*mode == 'r' ? stdin : stdout);
	if ((fp = fopen(name, mode)) == NULL)
		err(1, "%s", name);
	return (fp);
}

void
obsolete(char *argv[])
{
	size_t len;
	char *ap, *p, *start;

	while ((ap = *++argv)) {
		/* Return if "--" or not an option of any form. */
		if (ap[0] != '-') {
			if (ap[0] != '+')
				return;
		} else if (ap[1] == '-')
			return;
		if (!isdigit(ap[1]))
			continue;
		/*
		 * Digit signifies an old-style option.  Malloc space for dash,
		 * new option and argument.
		 */
		len = strlen(ap) + 3;
		if ((start = p = malloc(len)) == NULL)
			err(1, "malloc");
		*p++ = '-';
		*p++ = ap[0] == '+' ? 's' : 'f';
		(void)strlcpy(p, ap + 1, len - 2);
		*argv = start;
	}
}

__dead void
usage(void)
{
	extern char *__progname;

	(void)fprintf(stderr,
	    "usage: %s [-c] [-d | -u] [-f fields] [-s chars] [input_file [output_file]]\n",
	    __progname);
	exit(1);
}