xref: /freebsd/usr.bin/split/split.c (revision 2008043f386721d58158e37e0d7e50df8095942d)
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 #ifndef lint
34 static const char copyright[] =
35 "@(#) Copyright (c) 1987, 1993, 1994\n\
36 	The Regents of the University of California.  All rights reserved.\n";
37 #endif
38 
39 #ifndef lint
40 static const char sccsid[] = "@(#)split.c	8.2 (Berkeley) 4/16/94";
41 #endif
42 
43 #include <sys/param.h>
44 #include <sys/stat.h>
45 
46 #include <ctype.h>
47 #include <err.h>
48 #include <errno.h>
49 #include <fcntl.h>
50 #include <inttypes.h>
51 #include <libutil.h>
52 #include <limits.h>
53 #include <locale.h>
54 #include <stdbool.h>
55 #include <stdint.h>
56 #include <stdio.h>
57 #include <stdlib.h>
58 #include <string.h>
59 #include <unistd.h>
60 #include <regex.h>
61 #include <sysexits.h>
62 
63 #define DEFLINE	1000			/* Default num lines per file. */
64 
65 static off_t	 bytecnt;		/* Byte count to split on. */
66 static long	 chunks;		/* Chunks count to split into. */
67 static bool      clobber = true;        /* Whether to overwrite existing output files. */
68 static long	 numlines;		/* Line count to split on. */
69 static int	 file_open;		/* If a file open. */
70 static int	 ifd = -1, ofd = -1;	/* Input/output file descriptors. */
71 static char	 fname[MAXPATHLEN];	/* File name prefix. */
72 static regex_t	 rgx;
73 static int	 pflag;
74 static bool	 dflag;
75 static long	 sufflen = 2;		/* File name suffix length. */
76 static bool	 autosfx = true;	/* Whether to auto-extend the suffix length. */
77 
78 static void newfile(void);
79 static void split1(void);
80 static void split2(void);
81 static void split3(void);
82 static void usage(void) __dead2;
83 
84 int
85 main(int argc, char **argv)
86 {
87 	char errbuf[64];
88 	const char *p, *errstr;
89 	int ch, error;
90 
91 	setlocale(LC_ALL, "");
92 
93 	dflag = false;
94 	while ((ch = getopt(argc, argv, "0::1::2::3::4::5::6::7::8::9::a:b:cdl:n:p:")) != -1)
95 		switch (ch) {
96 		case '0': case '1': case '2': case '3': case '4':
97 		case '5': case '6': case '7': case '8': case '9':
98 			/*
99 			 * Undocumented kludge: split was originally designed
100 			 * to take a number after a dash.
101 			 */
102 			if (numlines != 0)
103 				usage();
104 			numlines = ch - '0';
105 			p = optarg ? optarg : "";
106 			while (numlines >= 0 && *p >= '0' && *p <= '9')
107 				numlines = numlines * 10 + *p++ - '0';
108 			if (numlines <= 0 || *p != '\0')
109 				errx(EX_USAGE, "%c%s: line count is invalid",
110 				    ch, optarg ? optarg : "");
111 			break;
112 		case 'a':		/* Suffix length */
113 			sufflen = strtonum(optarg, 0, INT_MAX, &errstr);
114 			if (errstr != NULL) {
115 				errx(EX_USAGE, "%s: suffix length is %s",
116 				    optarg, errstr);
117 			}
118 			if (sufflen == 0) {
119 				sufflen = 2;
120 				autosfx = true;
121 			} else {
122 				autosfx = false;
123 			}
124 			break;
125 		case 'b':		/* Byte count. */
126 			if (expand_number(optarg, &bytecnt) != 0) {
127 				errx(EX_USAGE, "%s: byte count is invalid",
128 				    optarg);
129 			}
130 			break;
131 		case 'c':               /* Continue, don't overwrite output files. */
132 			clobber = false;
133 			break;
134 		case 'd':		/* Decimal suffix */
135 			dflag = true;
136 			break;
137 		case 'l':		/* Line count. */
138 			if (numlines != 0)
139 				usage();
140 			numlines = strtonum(optarg, 1, LONG_MAX, &errstr);
141 			if (errstr != NULL) {
142 				errx(EX_USAGE, "%s: line count is %s",
143 				    optarg, errstr);
144 			}
145 			break;
146 		case 'n':		/* Chunks. */
147 			chunks = strtonum(optarg, 1, LONG_MAX, &errstr);
148 			if (errstr != NULL) {
149 				errx(EX_USAGE, "%s: number of chunks is %s",
150 				    optarg, errstr);
151 			}
152 			break;
153 
154 		case 'p':		/* pattern matching. */
155 			error = regcomp(&rgx, optarg, REG_EXTENDED|REG_NOSUB);
156 			if (error != 0) {
157 				regerror(error, &rgx, errbuf, sizeof(errbuf));
158 				errx(EX_USAGE, "%s: regex is invalid: %s",
159 				    optarg, errbuf);
160 			}
161 			pflag = 1;
162 			break;
163 		default:
164 			usage();
165 		}
166 	argv += optind;
167 	argc -= optind;
168 
169 	if (argc > 0) {			/* Input file. */
170 		if (strcmp(*argv, "-") == 0)
171 			ifd = STDIN_FILENO;
172 		else if ((ifd = open(*argv, O_RDONLY, 0)) < 0)
173 			err(EX_NOINPUT, "%s", *argv);
174 		++argv;
175 		--argc;
176 	}
177 	if (argc > 0) {			/* File name prefix. */
178 		if (strlcpy(fname, *argv, sizeof(fname)) >= sizeof(fname)) {
179 			errx(EX_USAGE, "%s: file name prefix is too long",
180 			    *argv);
181 		}
182 		++argv;
183 		--argc;
184 	}
185 	if (argc > 0)
186 		usage();
187 
188 	if (strlen(fname) + (unsigned long)sufflen >= sizeof(fname))
189 		errx(EX_USAGE, "suffix is too long");
190 	if (pflag && (numlines != 0 || bytecnt != 0 || chunks != 0))
191 		usage();
192 
193 	if (numlines == 0)
194 		numlines = DEFLINE;
195 	else if (bytecnt != 0 || chunks != 0)
196 		usage();
197 
198 	if (bytecnt != 0 && chunks != 0)
199 		usage();
200 
201 	if (ifd == -1)				/* Stdin by default. */
202 		ifd = 0;
203 
204 	if (bytecnt != 0) {
205 		split1();
206 		exit (0);
207 	} else if (chunks != 0) {
208 		split3();
209 		exit (0);
210 	}
211 	split2();
212 	if (pflag)
213 		regfree(&rgx);
214 	exit(0);
215 }
216 
217 /*
218  * split1 --
219  *	Split the input by bytes.
220  */
221 static void
222 split1(void)
223 {
224 	static char bfr[MAXBSIZE];
225 	off_t bcnt;
226 	char *C;
227 	ssize_t dist, len;
228 	int nfiles;
229 
230 	nfiles = 0;
231 
232 	for (bcnt = 0;;)
233 		switch ((len = read(ifd, bfr, sizeof(bfr)))) {
234 		case 0:
235 			exit(0);
236 		case -1:
237 			err(EX_IOERR, "read");
238 			/* NOTREACHED */
239 		default:
240 			if (!file_open) {
241 				if (chunks == 0 || nfiles < chunks) {
242 					newfile();
243 					nfiles++;
244 				}
245 			}
246 			if (bcnt + len >= bytecnt) {
247 				dist = bytecnt - bcnt;
248 				if (write(ofd, bfr, dist) != dist)
249 					err(EX_IOERR, "write");
250 				len -= dist;
251 				for (C = bfr + dist; len >= bytecnt;
252 				     len -= bytecnt, C += bytecnt) {
253 					if (chunks == 0 || nfiles < chunks) {
254 						newfile();
255 						nfiles++;
256 					}
257 					if (write(ofd, C, bytecnt) != bytecnt)
258 						err(EX_IOERR, "write");
259 				}
260 				if (len != 0) {
261 					if (chunks == 0 || nfiles < chunks) {
262 						newfile();
263 						nfiles++;
264 					}
265 					if (write(ofd, C, len) != len)
266 						err(EX_IOERR, "write");
267 				} else {
268 					file_open = 0;
269 				}
270 				bcnt = len;
271 			} else {
272 				bcnt += len;
273 				if (write(ofd, bfr, len) != len)
274 					err(EX_IOERR, "write");
275 			}
276 		}
277 }
278 
279 /*
280  * split2 --
281  *	Split the input by lines.
282  */
283 static void
284 split2(void)
285 {
286 	char *buf;
287 	size_t bufsize;
288 	ssize_t len;
289 	long lcnt = 0;
290 	FILE *infp;
291 
292 	buf = NULL;
293 	bufsize = 0;
294 
295 	/* Stick a stream on top of input file descriptor */
296 	if ((infp = fdopen(ifd, "r")) == NULL)
297 		err(EX_NOINPUT, "fdopen");
298 
299 	/* Process input one line at a time */
300 	while ((errno = 0, len = getline(&buf, &bufsize, infp)) > 0) {
301 		/* Check if we need to start a new file */
302 		if (pflag) {
303 			regmatch_t pmatch;
304 
305 			pmatch.rm_so = 0;
306 			pmatch.rm_eo = len - 1;
307 			if (regexec(&rgx, buf, 0, &pmatch, REG_STARTEND) == 0)
308 				newfile();
309 		} else if (lcnt++ == numlines) {
310 			newfile();
311 			lcnt = 1;
312 		}
313 
314 		/* Open output file if needed */
315 		if (!file_open)
316 			newfile();
317 
318 		/* Write out line */
319 		if (write(ofd, buf, len) != len)
320 			err(EX_IOERR, "write");
321 	}
322 
323 	/* EOF or error? */
324 	if ((len == -1 && errno != 0) || ferror(infp))
325 		err(EX_IOERR, "read");
326 	else
327 		exit(0);
328 }
329 
330 /*
331  * split3 --
332  *	Split the input into specified number of chunks
333  */
334 static void
335 split3(void)
336 {
337 	struct stat sb;
338 
339 	if (fstat(ifd, &sb) == -1) {
340 		err(1, "stat");
341 		/* NOTREACHED */
342 	}
343 
344 	if (chunks > sb.st_size) {
345 		errx(1, "can't split into more than %d files",
346 		    (int)sb.st_size);
347 		/* NOTREACHED */
348 	}
349 
350 	bytecnt = sb.st_size / chunks;
351 	split1();
352 }
353 
354 
355 /*
356  * newfile --
357  *	Open a new output file.
358  */
359 static void
360 newfile(void)
361 {
362 	long i, maxfiles, tfnum;
363 	static long fnum;
364 	static char *fpnt;
365 	char beg, end;
366 	int pattlen;
367 	int flags = O_WRONLY | O_CREAT | O_TRUNC;
368 
369 	if (!clobber)
370 		flags |= O_EXCL;
371 
372 	if (ofd == -1) {
373 		if (fname[0] == '\0') {
374 			fname[0] = 'x';
375 			fpnt = fname + 1;
376 		} else {
377 			fpnt = fname + strlen(fname);
378 		}
379 	} else if (close(ofd) != 0)
380 		err(1, "%s", fname);
381 
382 	again:
383 	if (dflag) {
384 		beg = '0';
385 		end = '9';
386 	}
387 	else {
388 		beg = 'a';
389 		end = 'z';
390 	}
391 	pattlen = end - beg + 1;
392 
393 	/*
394 	 * If '-a' is not specified, then we automatically expand the
395 	 * suffix length to accomodate splitting all input.  We do this
396 	 * by moving the suffix pointer (fpnt) forward and incrementing
397 	 * sufflen by one, thereby yielding an additional two characters
398 	 * and allowing all output files to sort such that 'cat *' yields
399 	 * the input in order.  I.e., the order is '... xyy xyz xzaaa
400 	 * xzaab ... xzyzy, xzyzz, xzzaaaa, xzzaaab' and so on.
401 	 */
402 	if (!dflag && autosfx && (fpnt[0] == 'y') &&
403 			strspn(fpnt+1, "z") == strlen(fpnt+1)) {
404 		fpnt = fname + strlen(fname) - sufflen;
405 		fpnt[sufflen + 2] = '\0';
406 		fpnt[0] = end;
407 		fpnt[1] = beg;
408 
409 		/*  Basename | Suffix
410 		 *  before:
411 		 *  x        | yz
412 		 *  after:
413 		 *  xz       | a.. */
414 		fpnt++;
415 		sufflen++;
416 
417 		/* Reset so we start back at all 'a's in our extended suffix. */
418 		fnum = 0;
419 	}
420 
421 	/* maxfiles = pattlen^sufflen, but don't use libm. */
422 	for (maxfiles = 1, i = 0; i < sufflen; i++)
423 		if (LONG_MAX / pattlen < maxfiles)
424 			errx(EX_USAGE, "suffix is too long (max %ld)", i);
425 		else
426 			maxfiles *= pattlen;
427 
428 	if (fnum == maxfiles)
429 		errx(EX_DATAERR, "too many files");
430 
431 	/* Generate suffix of sufflen letters */
432 	tfnum = fnum;
433 	i = sufflen - 1;
434 	do {
435 		fpnt[i] = tfnum % pattlen + beg;
436 		tfnum /= pattlen;
437 	} while (i-- > 0);
438 	fpnt[sufflen] = '\0';
439 
440 	++fnum;
441 	if ((ofd = open(fname, flags, DEFFILEMODE)) < 0) {
442 		if (!clobber && errno == EEXIST)
443 			goto again;
444 		err(EX_IOERR, "%s", fname);
445 	}
446 	file_open = 1;
447 }
448 
449 static void
450 usage(void)
451 {
452 	(void)fprintf(stderr,
453 "usage: split [-cd] [-l line_count] [-a suffix_length] [file [prefix]]\n"
454 "       split [-cd] -b byte_count[K|k|M|m|G|g] [-a suffix_length] [file [prefix]]\n"
455 "       split [-cd] -n chunk_count [-a suffix_length] [file [prefix]]\n"
456 "       split [-cd] -p pattern [-a suffix_length] [file [prefix]]\n");
457 	exit(EX_USAGE);
458 }
459