cat.c revision 246083 
1/*-
2 * Copyright (c) 1989, 1993
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Kevin Fall.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#if 0
34#ifndef lint
35static char const copyright[] =
36"@(#) Copyright (c) 1989, 1993\n\
37	The Regents of the University of California.  All rights reserved.\n";
38#endif /* not lint */
39#endif
40
41#ifndef lint
42#if 0
43static char sccsid[] = "@(#)cat.c	8.2 (Berkeley) 4/27/95";
44#endif
45#endif /* not lint */
46#include <sys/cdefs.h>
47__FBSDID("$FreeBSD: head/bin/cat/cat.c 246083 2013-01-29 18:19:40Z brooks $");
48
49#include <sys/param.h>
50#include <sys/stat.h>
51#ifndef NO_UDOM_SUPPORT
52#include <sys/socket.h>
53#include <sys/un.h>
54#include <errno.h>
55#endif
56
57#include <ctype.h>
58#include <err.h>
59#include <fcntl.h>
60#include <locale.h>
61#include <stddef.h>
62#include <stdio.h>
63#include <stdlib.h>
64#include <string.h>
65#include <unistd.h>
66
67static int bflag, eflag, lflag, nflag, sflag, tflag, vflag;
68static int rval;
69static const char *filename;
70
71static void usage(void);
72static void scanfiles(char *argv[], int cooked);
73static void cook_cat(FILE *);
74static void raw_cat(int);
75
76#ifndef NO_UDOM_SUPPORT
77static int udom_open(const char *path, int flags);
78#endif
79
80/*
81 * Memory strategy threshold, in pages: if physmem is larger than this,
82 * use a large buffer.
83 */
84#define	PHYSPAGES_THRESHOLD (32 * 1024)
85
86/* Maximum buffer size in bytes - do not allow it to grow larger than this. */
87#define	BUFSIZE_MAX (2 * 1024 * 1024)
88
89/*
90 * Small (default) buffer size in bytes. It's inefficient for this to be
91 * smaller than MAXPHYS.
92 */
93#define	BUFSIZE_SMALL (MAXPHYS)
94
95int
96main(int argc, char *argv[])
97{
98	int ch;
99	struct flock stdout_lock;
100
101	setlocale(LC_CTYPE, "");
102
103	while ((ch = getopt(argc, argv, "belnstuv")) != -1)
104		switch (ch) {
105		case 'b':
106			bflag = nflag = 1;	/* -b implies -n */
107			break;
108		case 'e':
109			eflag = vflag = 1;	/* -e implies -v */
110			break;
111		case 'l':
112			lflag = 1;
113			break;
114		case 'n':
115			nflag = 1;
116			break;
117		case 's':
118			sflag = 1;
119			break;
120		case 't':
121			tflag = vflag = 1;	/* -t implies -v */
122			break;
123		case 'u':
124			setbuf(stdout, NULL);
125			break;
126		case 'v':
127			vflag = 1;
128			break;
129		default:
130			usage();
131		}
132	argv += optind;
133
134	if (lflag) {
135		stdout_lock.l_len = 0;
136		stdout_lock.l_start = 0;
137		stdout_lock.l_type = F_WRLCK;
138		stdout_lock.l_whence = SEEK_SET;
139		if (fcntl(STDOUT_FILENO, F_SETLKW, &stdout_lock) == -1)
140			err(EXIT_FAILURE, "stdout");
141	}
142
143	if (bflag || eflag || nflag || sflag || tflag || vflag)
144		scanfiles(argv, 1);
145	else
146		scanfiles(argv, 0);
147	if (fclose(stdout))
148		err(1, "stdout");
149	exit(rval);
150	/* NOTREACHED */
151}
152
153static void
154usage(void)
155{
156	fprintf(stderr, "usage: cat [-belnstuv] [file ...]\n");
157	exit(1);
158	/* NOTREACHED */
159}
160
161static void
162scanfiles(char *argv[], int cooked)
163{
164	int fd, i;
165	char *path;
166	FILE *fp;
167
168	i = 0;
169	while ((path = argv[i]) != NULL || i == 0) {
170		if (path == NULL || strcmp(path, "-") == 0) {
171			filename = "stdin";
172			fd = STDIN_FILENO;
173		} else {
174			filename = path;
175			fd = open(path, O_RDONLY);
176#ifndef NO_UDOM_SUPPORT
177			if (fd < 0 && errno == EOPNOTSUPP)
178				fd = udom_open(path, O_RDONLY);
179#endif
180		}
181		if (fd < 0) {
182			warn("%s", path);
183			rval = 1;
184		} else if (cooked) {
185			if (fd == STDIN_FILENO)
186				cook_cat(stdin);
187			else {
188				fp = fdopen(fd, "r");
189				cook_cat(fp);
190				fclose(fp);
191			}
192		} else {
193			raw_cat(fd);
194			if (fd != STDIN_FILENO)
195				close(fd);
196		}
197		if (path == NULL)
198			break;
199		++i;
200	}
201}
202
203static void
204cook_cat(FILE *fp)
205{
206	int ch, gobble, line, prev;
207
208	/* Reset EOF condition on stdin. */
209	if (fp == stdin && feof(stdin))
210		clearerr(stdin);
211
212	line = gobble = 0;
213	for (prev = '\n'; (ch = getc(fp)) != EOF; prev = ch) {
214		if (prev == '\n') {
215			if (sflag) {
216				if (ch == '\n') {
217					if (gobble)
218						continue;
219					gobble = 1;
220				} else
221					gobble = 0;
222			}
223			if (nflag && (!bflag || ch != '\n')) {
224				(void)fprintf(stdout, "%6d\t", ++line);
225				if (ferror(stdout))
226					break;
227			}
228		}
229		if (ch == '\n') {
230			if (eflag && putchar('$') == EOF)
231				break;
232		} else if (ch == '\t') {
233			if (tflag) {
234				if (putchar('^') == EOF || putchar('I') == EOF)
235					break;
236				continue;
237			}
238		} else if (vflag) {
239			if (!isascii(ch) && !isprint(ch)) {
240				if (putchar('M') == EOF || putchar('-') == EOF)
241					break;
242				ch = toascii(ch);
243			}
244			if (iscntrl(ch)) {
245				if (putchar('^') == EOF ||
246				    putchar(ch == '\177' ? '?' :
247				    ch | 0100) == EOF)
248					break;
249				continue;
250			}
251		}
252		if (putchar(ch) == EOF)
253			break;
254	}
255	if (ferror(fp)) {
256		warn("%s", filename);
257		rval = 1;
258		clearerr(fp);
259	}
260	if (ferror(stdout))
261		err(1, "stdout");
262}
263
264static void
265raw_cat(int rfd)
266{
267	int off, wfd;
268	ssize_t nr, nw;
269	static size_t bsize;
270	static char *buf = NULL;
271	struct stat sbuf;
272
273	wfd = fileno(stdout);
274	if (buf == NULL) {
275		if (fstat(wfd, &sbuf))
276			err(1, "stdout");
277		if (S_ISREG(sbuf.st_mode)) {
278			/* If there's plenty of RAM, use a large copy buffer */
279			if (sysconf(_SC_PHYS_PAGES) > PHYSPAGES_THRESHOLD)
280				bsize = MIN(BUFSIZE_MAX, MAXPHYS * 8);
281			else
282				bsize = BUFSIZE_SMALL;
283		} else
284			bsize = MAX(sbuf.st_blksize,
285			    (blksize_t)sysconf(_SC_PAGESIZE));
286		if ((buf = malloc(bsize)) == NULL)
287			err(1, "malloc() failure of IO buffer");
288	}
289	while ((nr = read(rfd, buf, bsize)) > 0)
290		for (off = 0; nr; nr -= nw, off += nw)
291			if ((nw = write(wfd, buf + off, (size_t)nr)) < 0)
292				err(1, "stdout");
293	if (nr < 0) {
294		warn("%s", filename);
295		rval = 1;
296	}
297}
298
299#ifndef NO_UDOM_SUPPORT
300
301static int
302udom_open(const char *path, int flags)
303{
304	struct sockaddr_un sou;
305	int fd;
306	unsigned int len;
307
308	bzero(&sou, sizeof(sou));
309
310	/*
311	 * Construct the unix domain socket address and attempt to connect
312	 */
313	fd = socket(AF_UNIX, SOCK_STREAM, 0);
314	if (fd >= 0) {
315		sou.sun_family = AF_UNIX;
316		if ((len = strlcpy(sou.sun_path, path,
317		    sizeof(sou.sun_path))) >= sizeof(sou.sun_path)) {
318			errno = ENAMETOOLONG;
319			return (-1);
320		}
321		len = offsetof(struct sockaddr_un, sun_path[len+1]);
322
323		if (connect(fd, (void *)&sou, len) < 0) {
324			close(fd);
325			fd = -1;
326		}
327	}
328
329	/*
330	 * handle the open flags by shutting down appropriate directions
331	 */
332	if (fd >= 0) {
333		switch(flags & O_ACCMODE) {
334		case O_RDONLY:
335			if (shutdown(fd, SHUT_WR) == -1)
336				warn(NULL);
337			break;
338		case O_WRONLY:
339			if (shutdown(fd, SHUT_RD) == -1)
340				warn(NULL);
341			break;
342		default:
343			break;
344		}
345	}
346	return (fd);
347}
348
349#endif
350