Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.bin/tail/tail.c	Lines:	32	92	34.8 %
Date:	2016-12-06	Branches:	26	102	25.5 %


/*	$OpenBSD: tail.c,v 1.21 2016/02/03 12:23:57 halex Exp $	*/

/*-
 * Copyright (c) 1991, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Edward Sze-Tyan Wang.
 *
 * 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 <sys/types.h>
#include <sys/stat.h>

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

#include "extern.h"

int fflag, rflag, rval;
int is_stdin;

static void obsolete(char **);
static void usage(void);

int
main(int argc, char *argv[])
{
	struct tailfile *tf;
	off_t off = 0;
	enum STYLE style;
	int ch;
	int i;
	char *p;

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

	/*
	 * Tail's options are weird.  First, -n10 is the same as -n-10, not
	 * -n+10.  Second, the number options are 1 based and not offsets,
	 * so -n+1 is the first line, and -c-1 is the last byte.  Third, the
	 * number options for the -r option specify the number of things that
	 * get displayed, not the starting point in the file.  The one major
	 * incompatibility in this version as compared to historical versions
	 * is that the 'r' option couldn't be modified by the -lbc options,
	 * i.e. it was always done in lines.  This version treats -rc as a
	 * number of characters in reverse order.  Finally, the default for
	 * -r is the entire file, not 10 lines.
	 */
#define	ARG(units, forward, backward) {					\
	if (style)							\
		usage();						\
	off = strtoll(optarg, &p, 10) * (units);			\
	if (*p)								\
		errx(1, "illegal offset -- %s", optarg);		\
	switch(optarg[0]) {						\
	case '+':							\
		if (off)						\
			off -= (units);					\
			style = (forward);				\
		break;							\
	case '-':							\
		off = -off;						\
		/* FALLTHROUGH */					\
	default:							\
		style = (backward);					\
		break;							\
	}								\
}

	obsolete(argv);
	style = NOTSET;
	while ((ch = getopt(argc, argv, "b:c:fn:r")) != -1)
		switch(ch) {
		case 'b':
			ARG(512, FBYTES, RBYTES);
			break;
		case 'c':
			ARG(1, FBYTES, RBYTES);
			break;
		case 'f':
			fflag = 1;
			break;
		case 'n':
			ARG(1, FLINES, RLINES);
			break;
		case 'r':
			rflag = 1;
			break;
		case '?':
		default:
			usage();
		}
	argc -= optind;
	argv += optind;

	/*
	 * If displaying in reverse, don't permit follow option, and convert
	 * style values.
	 */
	if (rflag) {
		if (fflag)
			usage();
		if (style == FBYTES)
			style = RBYTES;
		else if (style == FLINES)
			style = RLINES;
	}

	/*
	 * If style not specified, the default is the whole file for -r, and
	 * the last 10 lines if not -r.
	 */
	if (style == NOTSET) {
		if (rflag) {
			off = 0;
			style = REVERSE;
		} else {
			off = 10;
			style = RLINES;
		}
	}

	if ((tf = reallocarray(NULL, argc ? argc : 1, sizeof(*tf))) == NULL)
		err(1, "reallocarray");

	if (argc) {
		for (i = 0; *argv; i++) {
			tf[i].fname = *argv++;
			if ((tf[i].fp = fopen(tf[i].fname, "r")) == NULL ||
			    fstat(fileno(tf[i].fp), &(tf[i].sb))) {
				ierr(tf[i].fname);
				i--;
				continue;
			}
		}
		if (rflag)
			reverse(tf, i, style, off);
		else
			forward(tf, i, style, off);
	}
	else {
		if (pledge("stdio wpath cpath rpath", NULL) == -1)
			err(1, "pledge");

		tf[0].fname = "stdin";
		tf[0].fp = stdin;
		is_stdin = 1;

		if (fstat(fileno(stdin), &(tf[0].sb))) {
			ierr(tf[0].fname);
			exit(1);
		}

		/*
		 * Determine if input is a pipe.  4.4BSD will set the SOCKET
		 * bit in the st_mode field for pipes.  Fix this then.
		 */
		if (lseek(fileno(tf[0].fp), (off_t)0, SEEK_CUR) == -1 &&
		    errno == ESPIPE) {
			errno = 0;
			fflag = 0;		/* POSIX.2 requires this. */
		}

		if (rflag)
			reverse(tf, 1, style, off);
		else
			forward(tf, 1, style, off);
	}
	exit(rval);
}

/*
 * Convert the obsolete argument form into something that getopt can handle.
 * This means that anything of the form [+-][0-9][0-9]*[lbc][fr] that isn't
 * the option argument for a -b, -c or -n option gets converted.
 */
static void
obsolete(char *argv[])
{
	char *ap, *p, *t;
	size_t len;
	char *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;

		switch(*++ap) {
		/* Old-style option. */
		case '0': case '1': case '2': case '3': case '4':
		case '5': case '6': case '7': case '8': case '9':

			/* Malloc space for dash, new option and argument. */
			len = strlen(*argv);
			if ((start = p = malloc(len + 4)) == NULL)
				err(1, NULL);
			*p++ = '-';

			/*
			 * Go to the end of the option argument.  Save off any
			 * trailing options (-3lf) and translate any trailing
			 * output style characters.
			 */
			t = *argv + len - 1;
			if (*t == 'f' || *t == 'r') {
				*p++ = *t;
				*t-- = '\0';
			}
			switch(*t) {
			case 'b':
				*p++ = 'b';
				*t = '\0';
				break;
			case 'c':
				*p++ = 'c';
				*t = '\0';
				break;
			case 'l':
				*t = '\0';
				/* FALLTHROUGH */
			case '0': case '1': case '2': case '3': case '4':
			case '5': case '6': case '7': case '8': case '9':
				*p++ = 'n';
				break;
			default:
				errx(1, "illegal option -- %s", *argv);
			}
			*p++ = *argv[0];
			(void)strlcpy(p, ap, start + len + 4 - p);
			*argv = start;
			continue;

		/*
		 * Options w/ arguments, skip the argument and continue
		 * with the next option.
		 */
		case 'b':
		case 'c':
		case 'n':
			if (!ap[1])
				++argv;
			/* FALLTHROUGH */
		/* Options w/o arguments, continue with the next option. */
		case 'f':
		case 'r':
			continue;

		/* Illegal option, return and let getopt handle it. */
		default:
			return;
		}
	}
}

static void
usage(void)
{
	(void)fprintf(stderr,
	    "usage: tail [-f | -r] "
	    "[-b number | -c number | -n number | -number] [file ...]\n");
	exit(1);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: tail.c,v 1.21 2016/02/03 12:23:57 halex Exp $ */
2
3			/*-
4			* Copyright (c) 1991, 1993
5			* The Regents of the University of California. All rights reserved.
6			*
7			* This code is derived from software contributed to Berkeley by
8			* Edward Sze-Tyan Wang.
9			*
10			* Redistribution and use in source and binary forms, with or without
11			* modification, are permitted provided that the following conditions
12			* are met:
13			* 1. Redistributions of source code must retain the above copyright
14			* notice, this list of conditions and the following disclaimer.
15			* 2. Redistributions in binary form must reproduce the above copyright
16			* notice, this list of conditions and the following disclaimer in the
17			* documentation and/or other materials provided with the distribution.
18			* 3. Neither the name of the University nor the names of its contributors
19			* may be used to endorse or promote products derived from this software
20			* without specific prior written permission.
21			*
22			* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
23			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25			* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
26			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32			* SUCH DAMAGE.
33			*/
34
35			#include <sys/types.h>
36			#include <sys/stat.h>
37
38			#include <err.h>
39			#include <errno.h>
40			#include <stdio.h>
41			#include <stdlib.h>
42			#include <string.h>
43			#include <unistd.h>
44
45			#include "extern.h"
46
47			int fflag, rflag, rval;
48			int is_stdin;
49
50			static void obsolete(char **);
51			static void usage(void);
52
53			int
54			main(int argc, char *argv[])
55		54	{
56			struct tailfile *tf;
57		54	off_t off = 0;
58			enum STYLE style;
59			int ch;
60			int i;
61			char *p;
62
63	✗✓	54	if (pledge("stdio rpath wpath cpath", NULL) == -1)
64			err(1, "pledge");
65
66			/*
67			* Tail's options are weird. First, -n10 is the same as -n-10, not
68			* -n+10. Second, the number options are 1 based and not offsets,
69			* so -n+1 is the first line, and -c-1 is the last byte. Third, the
70			* number options for the -r option specify the number of things that
71			* get displayed, not the starting point in the file. The one major
72			* incompatibility in this version as compared to historical versions
73			* is that the 'r' option couldn't be modified by the -lbc options,
74			* i.e. it was always done in lines. This version treats -rc as a
75			* number of characters in reverse order. Finally, the default for
76			* -r is the entire file, not 10 lines.
77			*/
78			#define ARG(units, forward, backward) { \
79			if (style) \
80			usage(); \
81			off = strtoll(optarg, &p, 10) * (units); \
82			if (*p) \
83			errx(1, "illegal offset -- %s", optarg); \
84			switch(optarg[0]) { \
85			case '+': \
86			if (off) \
87			off -= (units); \
88			style = (forward); \
89			break; \
90			case '-': \
91			off = -off; \
92			/* FALLTHROUGH */ \
93			default: \
94			style = (backward); \
95			break; \
96			} \
97			}
98
99		54	obsolete(argv);
100		54	style = NOTSET;
101	✓✓	162	while ((ch = getopt(argc, argv, "b:c:fn:r")) != -1)
102	✗✗✗✓ ✗✗	54	switch(ch) {
103			case 'b':
104			ARG(512, FBYTES, RBYTES);
105			break;
106			case 'c':
107			ARG(1, FBYTES, RBYTES);
108			break;
109			case 'f':
110			fflag = 1;
111			break;
112			case 'n':
113	✗✓✗✓ ✓✗✗✓ ✗	54	ARG(1, FLINES, RLINES);
114			break;
115			case 'r':
116			rflag = 1;
117			break;
118			case '?':
119			default:
120			usage();
121			}
122		54	argc -= optind;
123		54	argv += optind;
124
125			/*
126			* If displaying in reverse, don't permit follow option, and convert
127			* style values.
128			*/
129	✗✓	54	if (rflag) {
130			if (fflag)
131			usage();
132			if (style == FBYTES)
133			style = RBYTES;
134			else if (style == FLINES)
135			style = RLINES;
136			}
137
138			/*
139			* If style not specified, the default is the whole file for -r, and
140			* the last 10 lines if not -r.
141			*/
142	✗✓	54	if (style == NOTSET) {
143			if (rflag) {
144			off = 0;
145			style = REVERSE;
146			} else {
147			off = 10;
148			style = RLINES;
149			}
150			}
151
152	✗✓✗✓	54	if ((tf = reallocarray(NULL, argc ? argc : 1, sizeof(*tf))) == NULL)
153			err(1, "reallocarray");
154
155	✗✓	54	if (argc) {
156			for (i = 0; *argv; i++) {
157			tf[i].fname = *argv++;
158			if ((tf[i].fp = fopen(tf[i].fname, "r")) == NULL \|\|
159			fstat(fileno(tf[i].fp), &(tf[i].sb))) {
160			ierr(tf[i].fname);
161			i--;
162			continue;
163			}
164			}
165			if (rflag)
166			reverse(tf, i, style, off);
167			else
168			forward(tf, i, style, off);
169			}
170			else {
171	✗✓	54	if (pledge("stdio wpath cpath rpath", NULL) == -1)
172			err(1, "pledge");
173
174		54	tf[0].fname = "stdin";
175		54	tf[0].fp = stdin;
176		54	is_stdin = 1;
177
178	✓✗✗✓	54	if (fstat(fileno(stdin), &(tf[0].sb))) {
179			ierr(tf[0].fname);
180			exit(1);
181			}
182
183			/*
184			* Determine if input is a pipe. 4.4BSD will set the SOCKET
185			* bit in the st_mode field for pipes. Fix this then.
186			*/
187	✓✗✓✗ ✓✗	54	if (lseek(fileno(tf[0].fp), (off_t)0, SEEK_CUR) == -1 &&
188			errno == ESPIPE) {
189		54	errno = 0;
190		54	fflag = 0; /* POSIX.2 requires this. */
191			}
192
193	✗✓	54	if (rflag)
194			reverse(tf, 1, style, off);
195			else
196		54	forward(tf, 1, style, off);
197			}
198		54	exit(rval);
199			}
200
201			/*
202			* Convert the obsolete argument form into something that getopt can handle.
203			* This means that anything of the form [+-][0-9][0-9]*[lbc][fr] that isn't
204			* the option argument for a -b, -c or -n option gets converted.
205			*/
206			static void
207			obsolete(char *argv[])
208		54	{
209			char ap, p, *t;
210			size_t len;
211			char *start;
212
213	✓✓	162	while ((ap = *++argv)) {
214			/* Return if "--" or not an option of any form. */
215	✗✓	54	if (ap[0] != '-') {
216			if (ap[0] != '+')
217			return;
218	✗✓	54	} else if (ap[1] == '-')
219			return;
220
221	✗✓✗✗	54	switch(*++ap) {
222			/* Old-style option. */
223			case '0': case '1': case '2': case '3': case '4':
224			case '5': case '6': case '7': case '8': case '9':
225
226			/* Malloc space for dash, new option and argument. */
227			len = strlen(*argv);
228			if ((start = p = malloc(len + 4)) == NULL)
229			err(1, NULL);
230			*p++ = '-';
231
232			/*
233			* Go to the end of the option argument. Save off any
234			* trailing options (-3lf) and translate any trailing
235			* output style characters.
236			*/
237			t = *argv + len - 1;
238			if (t == 'f' \|\| t == 'r') {
239			p++ = t;
240			*t-- = '\0';
241			}
242			switch(*t) {
243			case 'b':
244			*p++ = 'b';
245			*t = '\0';
246			break;
247			case 'c':
248			*p++ = 'c';
249			*t = '\0';
250			break;
251			case 'l':
252			*t = '\0';
253			/* FALLTHROUGH */
254			case '0': case '1': case '2': case '3': case '4':
255			case '5': case '6': case '7': case '8': case '9':
256			*p++ = 'n';
257			break;
258			default:
259			errx(1, "illegal option -- %s", *argv);
260			}
261			p++ = argv[0];
262			(void)strlcpy(p, ap, start + len + 4 - p);
263			*argv = start;
264			continue;
265
266			/*
267			* Options w/ arguments, skip the argument and continue
268			* with the next option.
269			*/
270			case 'b':
271			case 'c':
272			case 'n':
273	✓✗	54	if (!ap[1])
274		54	++argv;
275			/* FALLTHROUGH */
276			/* Options w/o arguments, continue with the next option. */
277			case 'f':
278			case 'r':
279			continue;
280
281			/* Illegal option, return and let getopt handle it. */
282			default:
283			return;
284			}
285			}
286			}
287
288			static void
289			usage(void)
290			{
291			(void)fprintf(stderr,
292			"usage: tail [-f \| -r] "
293			"[-b number \| -c number \| -n number \| -number] [file ...]\n");
294			exit(1);
295			}