GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: usr.bin/head/head.c Lines: 25 40 62.5 %
Date: 2017-11-13 Branches: 27 46 58.7 %

Line Branch Exec Source
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/*	$OpenBSD: head.c,v 1.21 2016/03/20 17:14:51 tb Exp $	*/
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/*
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 * Copyright (c) 1980, 1987 Regents of the University of California.
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 * All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. Neither the name of the University nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 */
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#include <stdio.h>
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#include <stdlib.h>
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#include <ctype.h>
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#include <limits.h>
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#include <err.h>
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#include <errno.h>
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#include <unistd.h>
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static void usage(void);
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/*
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 * head - give the first few lines of a stream or of each of a set of files
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 *
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 * Bill Joy UCB August 24, 1977
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 */
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int
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main(int argc, char *argv[])
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{
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	FILE	*fp;
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	long	cnt;
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	int	ch, firsttime;
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	long	linecnt = 10;
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	char	*p = NULL;
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	int	status = 0;
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	if (pledge("stdio rpath flock cpath wpath", NULL) == -1)
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		err(1, "pledge");
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	/* handle obsolete -number syntax */
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	if (argc > 1 && argv[1][0] == '-' &&
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	    isdigit((unsigned char)argv[1][1])) {
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		p = argv[1] + 1;
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		argc--;
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		argv++;
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	}
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	while ((ch = getopt(argc, argv, "n:")) != -1) {
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		switch (ch) {
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		case 'n':
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			p = optarg;
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			break;
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		default:
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			usage();
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		}
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	}
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	argc -= optind, argv += optind;
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	if (p) {
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		const char *errstr;
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		linecnt = strtonum(p, 1, LONG_MAX, &errstr);
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		if (errstr)
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			errx(1, "line count %s: %s", errstr, p);
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	}
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	for (firsttime = 1; ; firsttime = 0) {
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		if (!*argv) {
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			if (!firsttime)
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				exit(status);
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			fp = stdin;
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			if (pledge("stdio flock rpath cpath wpath", NULL) == -1)
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				err(1, "pledge");
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		} else {
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			if ((fp = fopen(*argv, "r")) == NULL) {
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				warn("%s", *argv++);
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				status = 1;
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				continue;
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			}
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			if (argc > 1) {
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				if (!firsttime)
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					putchar('\n');
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				printf("==> %s <==\n", *argv);
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			}
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			++argv;
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		}
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		for (cnt = linecnt; cnt && !feof(fp); --cnt)
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			while ((ch = getc(fp)) != EOF)
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				if (putchar(ch) == '\n')
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					break;
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		fclose(fp);
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	}
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	/*NOTREACHED*/
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}
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static void
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usage(void)
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{
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	fputs("usage: head [-count | -n count] [file ...]\n", stderr);
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	exit(1);
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}