xref: /freebsd/usr.bin/split/split.c (revision d5b0e70f7e04d971691517ce1304d86a1e367e2e)
1 /*-
2  * SPDX-License-Identifier: BSD-3-Clause
3  *
4  * Copyright (c) 1987, 1993, 1994
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
34 
35 #ifndef lint
36 static const char copyright[] =
37 "@(#) Copyright (c) 1987, 1993, 1994\n\
38 	The Regents of the University of California.  All rights reserved.\n";
39 #endif
40 
41 #ifndef lint
42 static const char sccsid[] = "@(#)split.c	8.2 (Berkeley) 4/16/94";
43 #endif
44 
45 #include <sys/param.h>
46 #include <sys/types.h>
47 #include <sys/stat.h>
48 
49 #include <ctype.h>
50 #include <err.h>
51 #include <errno.h>
52 #include <fcntl.h>
53 #include <inttypes.h>
54 #include <libutil.h>
55 #include <limits.h>
56 #include <locale.h>
57 #include <stdbool.h>
58 #include <stdint.h>
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 #include <unistd.h>
63 #include <regex.h>
64 #include <sysexits.h>
65 
66 #define DEFLINE	1000			/* Default num lines per file. */
67 
68 static off_t	 bytecnt;		/* Byte count to split on. */
69 static off_t	 chunks = 0;		/* Chunks count to split into. */
70 static long	 numlines;		/* Line count to split on. */
71 static int	 file_open;		/* If a file open. */
72 static int	 ifd = -1, ofd = -1;	/* Input/output file descriptors. */
73 static char	 fname[MAXPATHLEN];	/* File name prefix. */
74 static regex_t	 rgx;
75 static int	 pflag;
76 static bool	 dflag;
77 static long	 sufflen = 2;		/* File name suffix length. */
78 
79 static void newfile(void);
80 static void split1(void);
81 static void split2(void);
82 static void split3(void);
83 static void usage(void);
84 
85 int
86 main(int argc, char **argv)
87 {
88 	int ch;
89 	int error;
90 	char *ep, *p;
91 
92 	setlocale(LC_ALL, "");
93 
94 	dflag = false;
95 	while ((ch = getopt(argc, argv, "0123456789a:b:dl:n:p:")) != -1)
96 		switch (ch) {
97 		case '0': case '1': case '2': case '3': case '4':
98 		case '5': case '6': case '7': case '8': case '9':
99 			/*
100 			 * Undocumented kludge: split was originally designed
101 			 * to take a number after a dash.
102 			 */
103 			if (numlines == 0) {
104 				p = argv[optind - 1];
105 				if (p[0] == '-' && p[1] == ch && !p[2])
106 					numlines = strtol(++p, &ep, 10);
107 				else
108 					numlines =
109 					    strtol(argv[optind] + 1, &ep, 10);
110 				if (numlines <= 0 || *ep)
111 					errx(EX_USAGE,
112 					    "%s: illegal line count", optarg);
113 			}
114 			break;
115 		case 'a':		/* Suffix length */
116 			if ((sufflen = strtol(optarg, &ep, 10)) <= 0 || *ep)
117 				errx(EX_USAGE,
118 				    "%s: illegal suffix length", optarg);
119 			break;
120 		case 'b':		/* Byte count. */
121 			errno = 0;
122 			error = expand_number(optarg, &bytecnt);
123 			if (error == -1)
124 				errx(EX_USAGE, "%s: offset too large", optarg);
125 			break;
126 		case 'd':		/* Decimal suffix */
127 			dflag = true;
128 			break;
129 		case 'l':		/* Line count. */
130 			if (numlines != 0)
131 				usage();
132 			if ((numlines = strtol(optarg, &ep, 10)) <= 0 || *ep)
133 				errx(EX_USAGE,
134 				    "%s: illegal line count", optarg);
135 			break;
136 		case 'n':		/* Chunks. */
137 			if (!isdigit((unsigned char)optarg[0]) ||
138 			    (chunks = (size_t)strtoul(optarg, &ep, 10)) == 0 ||
139 			    *ep != '\0') {
140 				errx(EX_USAGE, "%s: illegal number of chunks",
141 				     optarg);
142 			}
143 			break;
144 
145 		case 'p':		/* pattern matching. */
146 			if (regcomp(&rgx, optarg, REG_EXTENDED|REG_NOSUB) != 0)
147 				errx(EX_USAGE, "%s: illegal regexp", optarg);
148 			pflag = 1;
149 			break;
150 		default:
151 			usage();
152 		}
153 	argv += optind;
154 	argc -= optind;
155 
156 	if (*argv != NULL) {			/* Input file. */
157 		if (strcmp(*argv, "-") == 0)
158 			ifd = STDIN_FILENO;
159 		else if ((ifd = open(*argv, O_RDONLY, 0)) < 0)
160 			err(EX_NOINPUT, "%s", *argv);
161 		++argv;
162 	}
163 	if (*argv != NULL)			/* File name prefix. */
164 		if (strlcpy(fname, *argv++, sizeof(fname)) >= sizeof(fname))
165 			errx(EX_USAGE, "file name prefix is too long");
166 	if (*argv != NULL)
167 		usage();
168 
169 	if (strlen(fname) + (unsigned long)sufflen >= sizeof(fname))
170 		errx(EX_USAGE, "suffix is too long");
171 	if (pflag && (numlines != 0 || bytecnt != 0 || chunks != 0))
172 		usage();
173 
174 	if (numlines == 0)
175 		numlines = DEFLINE;
176 	else if (bytecnt != 0 || chunks != 0)
177 		usage();
178 
179 	if (bytecnt && chunks)
180 		usage();
181 
182 	if (ifd == -1)				/* Stdin by default. */
183 		ifd = 0;
184 
185 	if (bytecnt) {
186 		split1();
187 		exit (0);
188 	} else if (chunks) {
189 		split3();
190 		exit (0);
191 	}
192 	split2();
193 	if (pflag)
194 		regfree(&rgx);
195 	exit(0);
196 }
197 
198 /*
199  * split1 --
200  *	Split the input by bytes.
201  */
202 static void
203 split1(void)
204 {
205 	static char bfr[MAXBSIZE];
206 	off_t bcnt;
207 	char *C;
208 	ssize_t dist, len;
209 	int nfiles;
210 
211 	nfiles = 0;
212 
213 	for (bcnt = 0;;)
214 		switch ((len = read(ifd, bfr, sizeof(bfr)))) {
215 		case 0:
216 			exit(0);
217 		case -1:
218 			err(EX_IOERR, "read");
219 			/* NOTREACHED */
220 		default:
221 			if (!file_open) {
222 				if (!chunks || (nfiles < chunks)) {
223 					newfile();
224 					nfiles++;
225 				}
226 			}
227 			if (bcnt + len >= bytecnt) {
228 				dist = bytecnt - bcnt;
229 				if (write(ofd, bfr, dist) != dist)
230 					err(EX_IOERR, "write");
231 				len -= dist;
232 				for (C = bfr + dist; len >= bytecnt;
233 				    len -= bytecnt, C += bytecnt) {
234 					if (!chunks || (nfiles < chunks)) {
235 					newfile();
236 						nfiles++;
237 					}
238 					if (write(ofd,
239 					    C, bytecnt) != bytecnt)
240 						err(EX_IOERR, "write");
241 				}
242 				if (len != 0) {
243 					if (!chunks || (nfiles < chunks)) {
244 					newfile();
245 						nfiles++;
246 					}
247 					if (write(ofd, C, len) != len)
248 						err(EX_IOERR, "write");
249 				} else
250 					file_open = 0;
251 				bcnt = len;
252 			} else {
253 				bcnt += len;
254 				if (write(ofd, bfr, len) != len)
255 					err(EX_IOERR, "write");
256 			}
257 		}
258 }
259 
260 /*
261  * split2 --
262  *	Split the input by lines.
263  */
264 static void
265 split2(void)
266 {
267 	char *buf;
268 	size_t bufsize;
269 	ssize_t len;
270 	long lcnt = 0;
271 	FILE *infp;
272 
273 	buf = NULL;
274 	bufsize = 0;
275 
276 	/* Stick a stream on top of input file descriptor */
277 	if ((infp = fdopen(ifd, "r")) == NULL)
278 		err(EX_NOINPUT, "fdopen");
279 
280 	/* Process input one line at a time */
281 	while ((errno = 0, len = getline(&buf, &bufsize, infp)) > 0) {
282 		/* Check if we need to start a new file */
283 		if (pflag) {
284 			regmatch_t pmatch;
285 
286 			pmatch.rm_so = 0;
287 			pmatch.rm_eo = len - 1;
288 			if (regexec(&rgx, buf, 0, &pmatch, REG_STARTEND) == 0)
289 				newfile();
290 		} else if (lcnt++ == numlines) {
291 			newfile();
292 			lcnt = 1;
293 		}
294 
295 		/* Open output file if needed */
296 		if (!file_open)
297 			newfile();
298 
299 		/* Write out line */
300 		if (write(ofd, buf, len) != len)
301 			err(EX_IOERR, "write");
302 	}
303 
304 	/* EOF or error? */
305 	if ((len == -1 && errno != 0) || ferror(infp))
306 		err(EX_IOERR, "read");
307 	else
308 		exit(0);
309 }
310 
311 /*
312  * split3 --
313  *	Split the input into specified number of chunks
314  */
315 static void
316 split3(void)
317 {
318 	struct stat sb;
319 
320 	if (fstat(ifd, &sb) == -1) {
321 		err(1, "stat");
322 		/* NOTREACHED */
323 	}
324 
325 	if (chunks > sb.st_size) {
326 		errx(1, "can't split into more than %d files",
327 		    (int)sb.st_size);
328 		/* NOTREACHED */
329 	}
330 
331 	bytecnt = sb.st_size / chunks;
332 	split1();
333 }
334 
335 
336 /*
337  * newfile --
338  *	Open a new output file.
339  */
340 static void
341 newfile(void)
342 {
343 	long i, maxfiles, tfnum;
344 	static long fnum;
345 	static char *fpnt;
346 	char beg, end;
347 	int pattlen;
348 
349 	if (ofd == -1) {
350 		if (fname[0] == '\0') {
351 			fname[0] = 'x';
352 			fpnt = fname + 1;
353 		} else {
354 			fpnt = fname + strlen(fname);
355 		}
356 		ofd = fileno(stdout);
357 	}
358 
359 	if (dflag) {
360 		beg = '0';
361 		end = '9';
362 	}
363 	else {
364 		beg = 'a';
365 		end = 'z';
366 	}
367 	pattlen = end - beg + 1;
368 
369 	/* maxfiles = pattlen^sufflen, but don't use libm. */
370 	for (maxfiles = 1, i = 0; i < sufflen; i++)
371 		if (LONG_MAX / pattlen < maxfiles)
372 			errx(EX_USAGE, "suffix is too long (max %ld)", i);
373 		else
374 			maxfiles *= pattlen;
375 
376 	if (fnum == maxfiles)
377 		errx(EX_DATAERR, "too many files");
378 
379 	/* Generate suffix of sufflen letters */
380 	tfnum = fnum;
381 	i = sufflen - 1;
382 	do {
383 		fpnt[i] = tfnum % pattlen + beg;
384 		tfnum /= pattlen;
385 	} while (i-- > 0);
386 	fpnt[sufflen] = '\0';
387 
388 	++fnum;
389 	if (!freopen(fname, "w", stdout))
390 		err(EX_IOERR, "%s", fname);
391 	file_open = 1;
392 }
393 
394 static void
395 usage(void)
396 {
397 	(void)fprintf(stderr,
398 "usage: split [-l line_count] [-a suffix_length] [file [prefix]]\n"
399 "       split -b byte_count[K|k|M|m|G|g] [-a suffix_length] [file [prefix]]\n"
400 "       split -n chunk_count [-a suffix_length] [file [prefix]]\n"
401 "       split -p pattern [-a suffix_length] [file [prefix]]\n");
402 	exit(EX_USAGE);
403 }
404