xref: /freebsd/usr.bin/split/split.c (revision 389e4940069316fe667ffa263fa7d6390d0a960f)
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	 bfr[MAXBSIZE];		/* I/O buffer. */
74 static char	 fname[MAXPATHLEN];	/* File name prefix. */
75 static regex_t	 rgx;
76 static int	 pflag;
77 static bool	 dflag;
78 static long	 sufflen = 2;		/* File name suffix length. */
79 
80 static void newfile(void);
81 static void split1(void);
82 static void split2(void);
83 static void split3(void);
84 static void usage(void);
85 
86 int
87 main(int argc, char **argv)
88 {
89 	int ch;
90 	int error;
91 	char *ep, *p;
92 
93 	setlocale(LC_ALL, "");
94 
95 	dflag = false;
96 	while ((ch = getopt(argc, argv, "0123456789a:b:dl:n:p:")) != -1)
97 		switch (ch) {
98 		case '0': case '1': case '2': case '3': case '4':
99 		case '5': case '6': case '7': case '8': case '9':
100 			/*
101 			 * Undocumented kludge: split was originally designed
102 			 * to take a number after a dash.
103 			 */
104 			if (numlines == 0) {
105 				p = argv[optind - 1];
106 				if (p[0] == '-' && p[1] == ch && !p[2])
107 					numlines = strtol(++p, &ep, 10);
108 				else
109 					numlines =
110 					    strtol(argv[optind] + 1, &ep, 10);
111 				if (numlines <= 0 || *ep)
112 					errx(EX_USAGE,
113 					    "%s: illegal line count", optarg);
114 			}
115 			break;
116 		case 'a':		/* Suffix length */
117 			if ((sufflen = strtol(optarg, &ep, 10)) <= 0 || *ep)
118 				errx(EX_USAGE,
119 				    "%s: illegal suffix length", optarg);
120 			break;
121 		case 'b':		/* Byte count. */
122 			errno = 0;
123 			error = expand_number(optarg, &bytecnt);
124 			if (error == -1)
125 				errx(EX_USAGE, "%s: offset too large", optarg);
126 			break;
127 		case 'd':		/* Decimal suffix */
128 			dflag = true;
129 			break;
130 		case 'l':		/* Line count. */
131 			if (numlines != 0)
132 				usage();
133 			if ((numlines = strtol(optarg, &ep, 10)) <= 0 || *ep)
134 				errx(EX_USAGE,
135 				    "%s: illegal line count", optarg);
136 			break;
137 		case 'n':		/* Chunks. */
138 			if (!isdigit((unsigned char)optarg[0]) ||
139 			    (chunks = (size_t)strtoul(optarg, &ep, 10)) == 0 ||
140 			    *ep != '\0') {
141 				errx(EX_USAGE, "%s: illegal number of chunks",
142 				     optarg);
143 			}
144 			break;
145 
146 		case 'p':		/* pattern matching. */
147 			if (regcomp(&rgx, optarg, REG_EXTENDED|REG_NOSUB) != 0)
148 				errx(EX_USAGE, "%s: illegal regexp", optarg);
149 			pflag = 1;
150 			break;
151 		default:
152 			usage();
153 		}
154 	argv += optind;
155 	argc -= optind;
156 
157 	if (*argv != NULL) {			/* Input file. */
158 		if (strcmp(*argv, "-") == 0)
159 			ifd = STDIN_FILENO;
160 		else if ((ifd = open(*argv, O_RDONLY, 0)) < 0)
161 			err(EX_NOINPUT, "%s", *argv);
162 		++argv;
163 	}
164 	if (*argv != NULL)			/* File name prefix. */
165 		if (strlcpy(fname, *argv++, sizeof(fname)) >= sizeof(fname))
166 			errx(EX_USAGE, "file name prefix is too long");
167 	if (*argv != NULL)
168 		usage();
169 
170 	if (strlen(fname) + (unsigned long)sufflen >= sizeof(fname))
171 		errx(EX_USAGE, "suffix is too long");
172 	if (pflag && (numlines != 0 || bytecnt != 0 || chunks != 0))
173 		usage();
174 
175 	if (numlines == 0)
176 		numlines = DEFLINE;
177 	else if (bytecnt != 0 || chunks != 0)
178 		usage();
179 
180 	if (bytecnt && chunks)
181 		usage();
182 
183 	if (ifd == -1)				/* Stdin by default. */
184 		ifd = 0;
185 
186 	if (bytecnt) {
187 		split1();
188 		exit (0);
189 	} else if (chunks) {
190 		split3();
191 		exit (0);
192 	}
193 	split2();
194 	if (pflag)
195 		regfree(&rgx);
196 	exit(0);
197 }
198 
199 /*
200  * split1 --
201  *	Split the input by bytes.
202  */
203 static void
204 split1(void)
205 {
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, MAXBSIZE))) {
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 	long lcnt = 0;
268 	FILE *infp;
269 
270 	/* Stick a stream on top of input file descriptor */
271 	if ((infp = fdopen(ifd, "r")) == NULL)
272 		err(EX_NOINPUT, "fdopen");
273 
274 	/* Process input one line at a time */
275 	while (fgets(bfr, sizeof(bfr), infp) != NULL) {
276 		const int len = strlen(bfr);
277 
278 		/* If line is too long to deal with, just write it out */
279 		if (bfr[len - 1] != '\n')
280 			goto writeit;
281 
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, bfr, 0, &pmatch, REG_STARTEND) == 0)
289 				newfile();
290 		} else if (lcnt++ == numlines) {
291 			newfile();
292 			lcnt = 1;
293 		}
294 
295 writeit:
296 		/* Open output file if needed */
297 		if (!file_open)
298 			newfile();
299 
300 		/* Write out line */
301 		if (write(ofd, bfr, len) != len)
302 			err(EX_IOERR, "write");
303 	}
304 
305 	/* EOF or error? */
306 	if (ferror(infp))
307 		err(EX_IOERR, "read");
308 	else
309 		exit(0);
310 }
311 
312 /*
313  * split3 --
314  *	Split the input into specified number of chunks
315  */
316 static void
317 split3(void)
318 {
319 	struct stat sb;
320 
321 	if (fstat(ifd, &sb) == -1) {
322 		err(1, "stat");
323 		/* NOTREACHED */
324 	}
325 
326 	if (chunks > sb.st_size) {
327 		errx(1, "can't split into more than %d files",
328 		    (int)sb.st_size);
329 		/* NOTREACHED */
330 	}
331 
332 	bytecnt = sb.st_size / chunks;
333 	split1();
334 }
335 
336 
337 /*
338  * newfile --
339  *	Open a new output file.
340  */
341 static void
342 newfile(void)
343 {
344 	long i, maxfiles, tfnum;
345 	static long fnum;
346 	static char *fpnt;
347 	char beg, end;
348 	int pattlen;
349 
350 	if (ofd == -1) {
351 		if (fname[0] == '\0') {
352 			fname[0] = 'x';
353 			fpnt = fname + 1;
354 		} else {
355 			fpnt = fname + strlen(fname);
356 		}
357 		ofd = fileno(stdout);
358 	}
359 
360 	if (dflag) {
361 		beg = '0';
362 		end = '9';
363 	}
364 	else {
365 		beg = 'a';
366 		end = 'z';
367 	}
368 	pattlen = end - beg + 1;
369 
370 	/* maxfiles = pattlen^sufflen, but don't use libm. */
371 	for (maxfiles = 1, i = 0; i < sufflen; i++)
372 		if (LONG_MAX / pattlen < maxfiles)
373 			errx(EX_USAGE, "suffix is too long (max %ld)", i);
374 		else
375 			maxfiles *= pattlen;
376 
377 	if (fnum == maxfiles)
378 		errx(EX_DATAERR, "too many files");
379 
380 	/* Generate suffix of sufflen letters */
381 	tfnum = fnum;
382 	i = sufflen - 1;
383 	do {
384 		fpnt[i] = tfnum % pattlen + beg;
385 		tfnum /= pattlen;
386 	} while (i-- > 0);
387 	fpnt[sufflen] = '\0';
388 
389 	++fnum;
390 	if (!freopen(fname, "w", stdout))
391 		err(EX_IOERR, "%s", fname);
392 	file_open = 1;
393 }
394 
395 static void
396 usage(void)
397 {
398 	(void)fprintf(stderr,
399 "usage: split [-l line_count] [-a suffix_length] [file [prefix]]\n"
400 "       split -b byte_count[K|k|M|m|G|g] [-a suffix_length] [file [prefix]]\n"
401 "       split -n chunk_count [-a suffix_length] [file [prefix]]\n"
402 "       split -p pattern [-a suffix_length] [file [prefix]]\n");
403 	exit(EX_USAGE);
404 }
405