xref: /freebsd/bin/cat/cat.c (revision 145992504973bd16cf3518af9ba5ce185fefa82a)
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, 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 
100 	setlocale(LC_CTYPE, "");
101 
102 	while ((ch = getopt(argc, argv, "benstuv")) != -1)
103 		switch (ch) {
104 		case 'b':
105 			bflag = nflag = 1;	/* -b implies -n */
106 			break;
107 		case 'e':
108 			eflag = vflag = 1;	/* -e implies -v */
109 			break;
110 		case 'n':
111 			nflag = 1;
112 			break;
113 		case 's':
114 			sflag = 1;
115 			break;
116 		case 't':
117 			tflag = vflag = 1;	/* -t implies -v */
118 			break;
119 		case 'u':
120 			setbuf(stdout, NULL);
121 			break;
122 		case 'v':
123 			vflag = 1;
124 			break;
125 		default:
126 			usage();
127 		}
128 	argv += optind;
129 
130 	if (bflag || eflag || nflag || sflag || tflag || vflag)
131 		scanfiles(argv, 1);
132 	else
133 		scanfiles(argv, 0);
134 	if (fclose(stdout))
135 		err(1, "stdout");
136 	exit(rval);
137 	/* NOTREACHED */
138 }
139 
140 static void
141 usage(void)
142 {
143 	fprintf(stderr, "usage: cat [-benstuv] [file ...]\n");
144 	exit(1);
145 	/* NOTREACHED */
146 }
147 
148 static void
149 scanfiles(char *argv[], int cooked)
150 {
151 	int fd, i;
152 	char *path;
153 	FILE *fp;
154 
155 	i = 0;
156 	while ((path = argv[i]) != NULL || i == 0) {
157 		if (path == NULL || strcmp(path, "-") == 0) {
158 			filename = "stdin";
159 			fd = STDIN_FILENO;
160 		} else {
161 			filename = path;
162 			fd = open(path, O_RDONLY);
163 #ifndef NO_UDOM_SUPPORT
164 			if (fd < 0 && errno == EOPNOTSUPP)
165 				fd = udom_open(path, O_RDONLY);
166 #endif
167 		}
168 		if (fd < 0) {
169 			warn("%s", path);
170 			rval = 1;
171 		} else if (cooked) {
172 			if (fd == STDIN_FILENO)
173 				cook_cat(stdin);
174 			else {
175 				fp = fdopen(fd, "r");
176 				cook_cat(fp);
177 				fclose(fp);
178 			}
179 		} else {
180 			raw_cat(fd);
181 			if (fd != STDIN_FILENO)
182 				close(fd);
183 		}
184 		if (path == NULL)
185 			break;
186 		++i;
187 	}
188 }
189 
190 static void
191 cook_cat(FILE *fp)
192 {
193 	int ch, gobble, line, prev;
194 
195 	/* Reset EOF condition on stdin. */
196 	if (fp == stdin && feof(stdin))
197 		clearerr(stdin);
198 
199 	line = gobble = 0;
200 	for (prev = '\n'; (ch = getc(fp)) != EOF; prev = ch) {
201 		if (prev == '\n') {
202 			if (sflag) {
203 				if (ch == '\n') {
204 					if (gobble)
205 						continue;
206 					gobble = 1;
207 				} else
208 					gobble = 0;
209 			}
210 			if (nflag && (!bflag || ch != '\n')) {
211 				(void)fprintf(stdout, "%6d\t", ++line);
212 				if (ferror(stdout))
213 					break;
214 			}
215 		}
216 		if (ch == '\n') {
217 			if (eflag && putchar('$') == EOF)
218 				break;
219 		} else if (ch == '\t') {
220 			if (tflag) {
221 				if (putchar('^') == EOF || putchar('I') == EOF)
222 					break;
223 				continue;
224 			}
225 		} else if (vflag) {
226 			if (!isascii(ch) && !isprint(ch)) {
227 				if (putchar('M') == EOF || putchar('-') == EOF)
228 					break;
229 				ch = toascii(ch);
230 			}
231 			if (iscntrl(ch)) {
232 				if (putchar('^') == EOF ||
233 				    putchar(ch == '\177' ? '?' :
234 				    ch | 0100) == EOF)
235 					break;
236 				continue;
237 			}
238 		}
239 		if (putchar(ch) == EOF)
240 			break;
241 	}
242 	if (ferror(fp)) {
243 		warn("%s", filename);
244 		rval = 1;
245 		clearerr(fp);
246 	}
247 	if (ferror(stdout))
248 		err(1, "stdout");
249 }
250 
251 static void
252 raw_cat(int rfd)
253 {
254 	int off, wfd;
255 	ssize_t nr, nw;
256 	static size_t bsize;
257 	static char *buf = NULL;
258 	struct stat sbuf;
259 
260 	wfd = fileno(stdout);
261 	if (buf == NULL) {
262 		if (fstat(wfd, &sbuf))
263 			err(1, "stdout");
264 		if (S_ISREG(sbuf.st_mode)) {
265 			/* If there's plenty of RAM, use a large copy buffer */
266 			if (sysconf(_SC_PHYS_PAGES) > PHYSPAGES_THRESHOLD)
267 				bsize = MIN(BUFSIZE_MAX, MAXPHYS * 8);
268 			else
269 				bsize = BUFSIZE_SMALL;
270 		} else
271 			bsize = MAX(sbuf.st_blksize,
272 			    (blksize_t)sysconf(_SC_PAGESIZE));
273 		if ((buf = malloc(bsize)) == NULL)
274 			err(1, "malloc() failure of IO buffer");
275 	}
276 	while ((nr = read(rfd, buf, bsize)) > 0)
277 		for (off = 0; nr; nr -= nw, off += nw)
278 			if ((nw = write(wfd, buf + off, (size_t)nr)) < 0)
279 				err(1, "stdout");
280 	if (nr < 0) {
281 		warn("%s", filename);
282 		rval = 1;
283 	}
284 }
285 
286 #ifndef NO_UDOM_SUPPORT
287 
288 static int
289 udom_open(const char *path, int flags)
290 {
291 	struct sockaddr_un sou;
292 	int fd;
293 	unsigned int len;
294 
295 	bzero(&sou, sizeof(sou));
296 
297 	/*
298 	 * Construct the unix domain socket address and attempt to connect
299 	 */
300 	fd = socket(AF_UNIX, SOCK_STREAM, 0);
301 	if (fd >= 0) {
302 		sou.sun_family = AF_UNIX;
303 		if ((len = strlcpy(sou.sun_path, path,
304 		    sizeof(sou.sun_path))) >= sizeof(sou.sun_path)) {
305 			errno = ENAMETOOLONG;
306 			return (-1);
307 		}
308 		len = offsetof(struct sockaddr_un, sun_path[len+1]);
309 
310 		if (connect(fd, (void *)&sou, len) < 0) {
311 			close(fd);
312 			fd = -1;
313 		}
314 	}
315 
316 	/*
317 	 * handle the open flags by shutting down appropriate directions
318 	 */
319 	if (fd >= 0) {
320 		switch(flags & O_ACCMODE) {
321 		case O_RDONLY:
322 			if (shutdown(fd, SHUT_WR) == -1)
323 				warn(NULL);
324 			break;
325 		case O_WRONLY:
326 			if (shutdown(fd, SHUT_RD) == -1)
327 				warn(NULL);
328 			break;
329 		default:
330 			break;
331 		}
332 	}
333 	return (fd);
334 }
335 
336 #endif
337