xref: /illumos-gate/usr/src/lib/libgen/common/reg_compile.c (revision 50450c3dedc4cfa86ef99c6d9aee64f2a5ea0511)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1988 AT&T	*/
28 /*	  All Rights Reserved	*/
29 
30 #include <sys/types.h>
31 #include <ctype.h>
32 #include <limits.h>
33 #include <stdlib.h>
34 #include <string.h>
35 #include <thread.h>
36 #include <pthread.h>
37 #include <widec.h> /* Defines multibyte and WCHAR_CSMASK for valid_range(). */
38 #include "_range.h"
39 #include "_regexp.h"
40 
41 #define	MBYTE_SIZE 255
42 
43 #define	GETC() ((unsigned char)*sp++)
44 #define	PEEKC() ((unsigned char)*sp)
45 #define	ERROR(c) { \
46 			regerrno = c; \
47 			goto out; \
48 		    }
49 
50 #define	Popwchar	oldsp = sp; \
51 			if (!multibyte || (unsigned char) *sp <= 0177) { \
52 				n = 1; \
53 				c = (wchar_t)(unsigned char)*sp++; \
54 			} else { \
55 				if ((n = mbtowc(&cl, sp, MB_LEN_MAX)) == -1) \
56 					ERROR(67) \
57 				sp += n; \
58 				c = cl; \
59 			}
60 
61 int	nbra = 0, regerrno = 0, reglength = 0;
62 
63 static unsigned char	_bittab[] = { 1, 2, 4, 8, 16, 32, 64, 128 };
64 
65 #ifdef  _REENTRANT
66 typedef struct _vars_storage {
67 	int	nbra, regerrno, reglength;
68 } vars_storage;
69 
70 static thread_key_t key = THR_ONCE_KEY;
71 
72 static vars_storage *
_get_vars_storage(thread_key_t * keyp)73 _get_vars_storage(thread_key_t *keyp)
74 {
75 	vars_storage *vars;
76 
77 	if (thr_keycreate_once(keyp, free) != 0)
78 		return (NULL);
79 	vars = pthread_getspecific(*keyp);
80 	if (vars == NULL) {
81 		vars = calloc(1, sizeof (vars_storage));
82 		if (thr_setspecific(*keyp, vars) != 0) {
83 			if (vars)
84 				(void) free(vars);
85 			vars = NULL;
86 		}
87 	}
88 	return (vars);
89 }
90 
91 int *
___nbra(void)92 ___nbra(void)
93 {
94 	if (thr_main())
95 		return (&nbra);
96 	else {
97 		vars_storage *vars = _get_vars_storage(&key);
98 		return (&vars->nbra);
99 	}
100 }
101 
102 int *
___regerrno(void)103 ___regerrno(void)
104 {
105 	if (thr_main())
106 		return (&regerrno);
107 	else {
108 		vars_storage *vars = _get_vars_storage(&key);
109 		return (&vars->regerrno);
110 	}
111 }
112 
113 int *
___reglength(void)114 ___reglength(void)
115 {
116 	if (thr_main())
117 		return (&reglength);
118 	else {
119 		vars_storage *vars = _get_vars_storage(&key);
120 		return (&vars->reglength);
121 	}
122 }
123 
124 #undef nbra
125 #define	nbra (*(___nbra()))
126 #undef regerrno
127 #define	regerrno (*(___regerrno()))
128 #undef reglength
129 #define	reglength (*(___reglength()))
130 
131 #endif	/* _REENTRANT */
132 
133 char *_compile(const char *, char *, char *, int);
134 
135 char *
compile(const char * sp,char * ep,char * endbuf)136 compile(const char *sp, char *ep, char *endbuf)
137 {
138 	return (_compile(sp, ep, endbuf, 0));
139 }
140 
141 char *
_compile(const char * sp,char * ep,char * endbuf,int viflag)142 _compile(const char *sp, char *ep, char *endbuf, int viflag)
143 {
144 	wchar_t		c;
145 	int		n;
146 	wchar_t		d;
147 	const char	*oldsp;
148 	char		*lastep;
149 	int		cclcnt;
150 	char		bracket[NBRA], *bracketp;
151 	int		closed;
152 	int		neg;
153 	int		alloc;
154 	wchar_t		lc, cl;
155 	int		i, cflg;
156 	char		*expbuf = ep;
157 	char		*start;
158 
159 	regerrno = 0;
160 	reglength = 0;
161 	lastep = 0;
162 	bracketp = bracket;
163 	closed = 0;
164 	alloc = 0;
165 
166 	oldsp = sp;
167 	if ((c = *sp++) == '\0') {
168 		if (ep == (char *)0 || ep[1] == 0)
169 			ERROR(41);
170 		goto out;
171 	}
172 	nbra = 0;
173 	if (ep == (char *)0) {
174 		/* malloc space */
175 		const char *startsp = oldsp;
176 		n = 0;
177 		while ((d = *startsp++) != 0) {
178 			if (d == '[')
179 				n += 33; /* add room for bitmaps */
180 		}
181 		n += 2 * (startsp - oldsp) + 3;
182 		if ((ep = malloc(n)) == (char *)0)
183 			ERROR(50);
184 		expbuf = ep;
185 		alloc = 1;
186 		endbuf = ep + n;
187 	}
188 
189 	if (c == '^')
190 		*ep++ = 1;
191 	else  {
192 		*ep++ = 0;
193 		sp--;
194 	}
195 
196 	endbuf--; /* avoid extra check for overflow */
197 	for (;;) {
198 		if (ep >= endbuf)
199 			ERROR(50);
200 		Popwchar;
201 		if (c != '*' && ((c != '\\') || (PEEKC() != '{')))
202 			lastep = ep;
203 		if (c == '\0') {
204 			*ep++ = CCEOF;
205 			if (bracketp != bracket)
206 				ERROR(42);
207 			goto out;
208 		}
209 		switch (c) {
210 
211 		case '.':
212 			*ep++ = CDOT;
213 			continue;
214 
215 		case '*':
216 			if (lastep == 0 || *lastep == CBRA ||*lastep == CKET ||
217 			    *lastep == CBRC || *lastep == CLET)
218 				goto defchar;
219 			*lastep |= STAR;
220 			continue;
221 
222 		case '$':
223 			/* look one character ahead to see if $ means */
224 			/* to anchor match at end of line */
225 			if ((d = PEEKC()) != '\0')
226 				goto defchar;
227 			*ep++ = CDOL;
228 			continue;
229 
230 		case '[':
231 			start = ep + 34;
232 			if (start > endbuf)
233 				ERROR(50);
234 
235 			*ep++ = CCL;
236 			lc = 0;
237 			for (i = 0; i < 32; i++)
238 				ep[i] = 0;
239 
240 			neg = 0;
241 			Popwchar;
242 			if (c == '^') {
243 				neg = 1;
244 				Popwchar;
245 			}
246 			if (multibyte) {
247 				if (neg) {
248 					/* do not negate bitmap for */
249 					/* for multibyte characters */
250 					neg = 0;
251 					ep[-1] = NMCCL;
252 					/* turn off null byte */
253 					ep[0] |= 01;
254 				} else
255 					ep[-1] = MCCL;
256 			}
257 			do {
258 				if (c == '\0')
259 					ERROR(49);
260 				if (c == '-' && lc != 0) {
261 					Popwchar;
262 					if (c == '\0')
263 						ERROR(49);
264 					if (c == ']') {
265 						PLACE('-');
266 						break;
267 					}
268 					/*
269 					 * ranges do not span code sets
270 					 */
271 					if (!multibyte || c <= 0177)
272 						while (lc < c) {
273 							PLACE(lc);
274 							lc++;
275 						}
276 					else
277 					if (valid_range(lc, c) && lc < c)
278 						/* insert '-' for range */
279 						*start++ = '-';
280 					if (viflag & 1)
281 						lc = 0;
282 					else
283 						lc = c;
284 				} else
285 				if (c == '\\' && (viflag & 1) &&
286 				    strchr("\\^-]", PEEKC())) {
287 					c = GETC();
288 					lc = c;
289 				} else
290 					lc = c;
291 				/* put eight bit characters into bitmap */
292 				if (!multibyte || c <= 0177 || c <= 0377 &&
293 				    iscntrl((int)c))
294 					PLACE(c);
295 				else {
296 					/*
297 					 * insert individual bytes of
298 					 * multibyte characters after
299 					 * bitmap
300 					 */
301 					if (start + n > endbuf)
302 						ERROR(50);
303 					while (n--)
304 						*start++ = *oldsp++;
305 				}
306 				Popwchar;
307 			} while (c != ']');
308 
309 			if (neg) {
310 				for (cclcnt = 0; cclcnt < 32; cclcnt++)
311 					ep[cclcnt] ^= 0377;
312 				ep[0] &= 0376;
313 			}
314 			ep += 32;
315 			if (multibyte) {
316 				/*
317 				 * Only allow 256 bytes to
318 				 * represent multibyte characters
319 				 * character class
320 				 */
321 				if (start - ep > MBYTE_SIZE)
322 					ERROR(50);
323 				*ep = (char)(start - ep);
324 				ep = start;
325 			}
326 			continue;
327 
328 		case '\\':
329 			Popwchar;
330 			switch (c) {
331 
332 			case '(':
333 				if (nbra >= NBRA)
334 					ERROR(43);
335 				*bracketp++ = nbra;
336 				*ep++ = CBRA;
337 				*ep++ = nbra++;
338 				continue;
339 
340 			case ')':
341 				if (bracketp <= bracket)
342 					ERROR(42);
343 				*ep++ = CKET;
344 				*ep++ = *--bracketp;
345 				closed++;
346 				continue;
347 
348 			case '{':
349 				if (lastep == (char *)0)
350 					goto defchar;
351 				*lastep |= RNGE;
352 				cflg = 0;
353 				c = GETC();
354 			nlim:
355 				i = 0;
356 				do {
357 					if ('0' <= c && c <= '9')
358 						i = 10 * i + (int)c - '0';
359 					else
360 						ERROR(16);
361 				} while (((c = GETC()) != '\\') && (c != ','));
362 				if (i > MBYTE_SIZE)
363 					ERROR(11);
364 				*ep++ = (char)i;
365 				if (c == ',') {
366 					if (cflg++)
367 						ERROR(44);
368 					if ((c = GETC()) == '\\')
369 						*ep++ = (char)MBYTE_SIZE;
370 					else
371 						goto nlim;
372 						/* get 2'nd number */
373 				}
374 				if (GETC() != '}')
375 					ERROR(45);
376 				if (!cflg)	/* one number */
377 					*ep++ = (char)i;
378 				else
379 				if ((int)(unsigned char)ep[-1] <
380 				    (int)(unsigned char)ep[-2])
381 					ERROR(46);
382 				continue;
383 
384 			case 'n':
385 				c = '\n';
386 				goto defchar;
387 
388 			case '<':
389 				*ep++ = CBRC;
390 				continue;
391 
392 			case '>':
393 				*ep++ = CLET;
394 				continue;
395 
396 			default:
397 				if (c >= '1' && c <= '9') {
398 					if ((c -= '1') >= closed)
399 						ERROR(25);
400 					*ep++ = CBACK;
401 					*ep++ = (char)c;
402 					continue;
403 				}
404 				break;
405 			}
406 
407 			/*
408 			 * Drop through to default to use \ to turn off
409 			 * special chars
410 			 */
411 			/* FALLTHROUGH */
412 		defchar:
413 		default:
414 			lastep = ep;
415 			if (!multibyte || c <= 0177) {
416 				/* 8-bit character */
417 				*ep++ = CCHR;
418 				*ep++ = (char)c;
419 			} else {
420 				/* multibyte character */
421 				*ep++ = MCCHR;
422 				if (ep + n > endbuf)
423 					ERROR(50);
424 				while (n--)
425 					*ep++ = *oldsp++;
426 			}
427 		}
428 	}
429 out:
430 	if (regerrno) {
431 		if (alloc)
432 			free(expbuf);
433 		return ((char *)0);
434 	}
435 	reglength = (int)(ep - expbuf);
436 	if (alloc)
437 		return (expbuf);
438 	return (ep);
439 }
440