xref: /freebsd/bin/cat/cat.c (revision d184218c)
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
35 static 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
43 static char sccsid[] = "@(#)cat.c	8.2 (Berkeley) 4/27/95";
44 #endif
45 #endif /* not lint */
46 #include <sys/cdefs.h>
47 __FBSDID("$FreeBSD$");
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 
67 static int bflag, eflag, lflag, nflag, sflag, tflag, vflag;
68 static int rval;
69 static const char *filename;
70 
71 static void usage(void);
72 static void scanfiles(char *argv[], int cooked);
73 static void cook_cat(FILE *);
74 static void raw_cat(int);
75 
76 #ifndef NO_UDOM_SUPPORT
77 static 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 
95 int
96 main(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 
153 static void
154 usage(void)
155 {
156 	fprintf(stderr, "usage: cat [-belnstuv] [file ...]\n");
157 	exit(1);
158 	/* NOTREACHED */
159 }
160 
161 static void
162 scanfiles(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 
203 static void
204 cook_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 
264 static void
265 raw_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 
301 static int
302 udom_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