xref: /freebsd/bin/cat/cat.c (revision 8fc257994d0ce2396196d7a06d50d20c8015f4b7)
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 <stdio.h>
62 #include <stdlib.h>
63 #include <string.h>
64 #include <unistd.h>
65 #include <stddef.h>
66 
67 int bflag, eflag, nflag, sflag, tflag, vflag;
68 int rval;
69 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 /* Memory strategy threshold, in pages: if physmem is larger then this, use a
81  * large buffer */
82 #define PHYSPAGES_THRESHOLD (32*1024)
83 
84 /* Maximum buffer size in bytes - do not allow it to grow larger than this */
85 #define BUFSIZE_MAX (2*1024*1024)
86 
87 /* Small (default) buffer size in bytes. It's inefficient for this to be
88  * smaller than MAXPHYS */
89 #define BUFSIZE_SMALL (MAXPHYS)
90 
91 int
92 main(int argc, char *argv[])
93 {
94 	int ch;
95 
96 	setlocale(LC_CTYPE, "");
97 
98 	while ((ch = getopt(argc, argv, "benstuv")) != -1)
99 		switch (ch) {
100 		case 'b':
101 			bflag = nflag = 1;	/* -b implies -n */
102 			break;
103 		case 'e':
104 			eflag = vflag = 1;	/* -e implies -v */
105 			break;
106 		case 'n':
107 			nflag = 1;
108 			break;
109 		case 's':
110 			sflag = 1;
111 			break;
112 		case 't':
113 			tflag = vflag = 1;	/* -t implies -v */
114 			break;
115 		case 'u':
116 			setbuf(stdout, NULL);
117 			break;
118 		case 'v':
119 			vflag = 1;
120 			break;
121 		default:
122 			usage();
123 		}
124 	argv += optind;
125 
126 	if (bflag || eflag || nflag || sflag || tflag || vflag)
127 		scanfiles(argv, 1);
128 	else
129 		scanfiles(argv, 0);
130 	if (fclose(stdout))
131 		err(1, "stdout");
132 	exit(rval);
133 	/* NOTREACHED */
134 }
135 
136 static void
137 usage(void)
138 {
139 	fprintf(stderr, "usage: cat [-benstuv] [file ...]\n");
140 	exit(1);
141 	/* NOTREACHED */
142 }
143 
144 static void
145 scanfiles(char *argv[], int cooked)
146 {
147 	int i = 0;
148 	char *path;
149 	FILE *fp;
150 
151 	while ((path = argv[i]) != NULL || i == 0) {
152 		int fd;
153 
154 		if (path == NULL || strcmp(path, "-") == 0) {
155 			filename = "stdin";
156 			fd = STDIN_FILENO;
157 		} else {
158 			filename = path;
159 			fd = open(path, O_RDONLY);
160 #ifndef NO_UDOM_SUPPORT
161 			if (fd < 0 && errno == EOPNOTSUPP)
162 				fd = udom_open(path, O_RDONLY);
163 #endif
164 		}
165 		if (fd < 0) {
166 			warn("%s", path);
167 			rval = 1;
168 		} else if (cooked) {
169 			if (fd == STDIN_FILENO)
170 				cook_cat(stdin);
171 			else {
172 				fp = fdopen(fd, "r");
173 				cook_cat(fp);
174 				fclose(fp);
175 			}
176 		} else {
177 			raw_cat(fd);
178 			if (fd != STDIN_FILENO)
179 				close(fd);
180 		}
181 		if (path == NULL)
182 			break;
183 		++i;
184 	}
185 }
186 
187 static void
188 cook_cat(FILE *fp)
189 {
190 	int ch, gobble, line, prev;
191 
192 	/* Reset EOF condition on stdin. */
193 	if (fp == stdin && feof(stdin))
194 		clearerr(stdin);
195 
196 	line = gobble = 0;
197 	for (prev = '\n'; (ch = getc(fp)) != EOF; prev = ch) {
198 		if (prev == '\n') {
199 			if (sflag) {
200 				if (ch == '\n') {
201 					if (gobble)
202 						continue;
203 					gobble = 1;
204 				} else
205 					gobble = 0;
206 			}
207 			if (nflag && (!bflag || ch != '\n')) {
208 				(void)fprintf(stdout, "%6d\t", ++line);
209 				if (ferror(stdout))
210 					break;
211 			}
212 		}
213 		if (ch == '\n') {
214 			if (eflag && putchar('$') == EOF)
215 				break;
216 		} else if (ch == '\t') {
217 			if (tflag) {
218 				if (putchar('^') == EOF || putchar('I') == EOF)
219 					break;
220 				continue;
221 			}
222 		} else if (vflag) {
223 			if (!isascii(ch) && !isprint(ch)) {
224 				if (putchar('M') == EOF || putchar('-') == EOF)
225 					break;
226 				ch = toascii(ch);
227 			}
228 			if (iscntrl(ch)) {
229 				if (putchar('^') == EOF ||
230 				    putchar(ch == '\177' ? '?' :
231 				    ch | 0100) == EOF)
232 					break;
233 				continue;
234 			}
235 		}
236 		if (putchar(ch) == EOF)
237 			break;
238 	}
239 	if (ferror(fp)) {
240 		warn("%s", filename);
241 		rval = 1;
242 		clearerr(fp);
243 	}
244 	if (ferror(stdout))
245 		err(1, "stdout");
246 }
247 
248 static void
249 raw_cat(int rfd)
250 {
251 	int off, wfd;
252 	ssize_t nr, nw;
253 	static size_t bsize;
254 	static char *buf = NULL;
255 	struct stat sbuf;
256 
257 	wfd = fileno(stdout);
258 	if (buf == NULL) {
259 		if (fstat(wfd, &sbuf))
260 			err(1, "%s", filename);
261 		if (S_ISREG(sbuf.st_mode)) {
262 			/* If there's plenty of RAM, use a large copy buffer */
263 			if (sysconf(_SC_PHYS_PAGES) > PHYSPAGES_THRESHOLD)
264 				bsize = MIN(BUFSIZE_MAX, MAXPHYS*8);
265 			else
266 				bsize = BUFSIZE_SMALL;
267 		} else
268 			bsize = MAX(sbuf.st_blksize,
269 					(blksize_t)sysconf(_SC_PAGESIZE));
270 		if ((buf = malloc(bsize)) == NULL)
271 			err(1, "malloc() failure of IO buffer");
272 	}
273 	while ((nr = read(rfd, buf, bsize)) > 0)
274 		for (off = 0; nr; nr -= nw, off += nw)
275 			if ((nw = write(wfd, buf + off, (size_t)nr)) < 0)
276 				err(1, "stdout");
277 	if (nr < 0) {
278 		warn("%s", filename);
279 		rval = 1;
280 	}
281 }
282 
283 #ifndef NO_UDOM_SUPPORT
284 
285 static int
286 udom_open(const char *path, int flags)
287 {
288 	struct sockaddr_un sou;
289 	int fd;
290 	unsigned int len;
291 
292 	bzero(&sou, sizeof(sou));
293 
294 	/*
295 	 * Construct the unix domain socket address and attempt to connect
296 	 */
297 	fd = socket(AF_UNIX, SOCK_STREAM, 0);
298 	if (fd >= 0) {
299 		sou.sun_family = AF_UNIX;
300 		if ((len = strlcpy(sou.sun_path, path,
301 		    sizeof(sou.sun_path))) >= sizeof(sou.sun_path)) {
302 			errno = ENAMETOOLONG;
303 			return (-1);
304 		}
305 		len = offsetof(struct sockaddr_un, sun_path[len+1]);
306 
307 		if (connect(fd, (void *)&sou, len) < 0) {
308 			close(fd);
309 			fd = -1;
310 		}
311 	}
312 
313 	/*
314 	 * handle the open flags by shutting down appropriate directions
315 	 */
316 	if (fd >= 0) {
317 		switch(flags & O_ACCMODE) {
318 		case O_RDONLY:
319 			if (shutdown(fd, SHUT_WR) == -1)
320 				warn(NULL);
321 			break;
322 		case O_WRONLY:
323 			if (shutdown(fd, SHUT_RD) == -1)
324 				warn(NULL);
325 			break;
326 		default:
327 			break;
328 		}
329 	}
330 	return(fd);
331 }
332 
333 #endif
334