regcomp.c (2393B)
1 /* 2 * Changes by Gunnar Ritter, Freiburg i. Br., Germany, November 2002. 3 * 4 * Sccsid @(#)regcomp.c 1.6 (gritter) 9/22/03 5 */ 6 /* UNIX(R) Regular Expresssion Library 7 * 8 * Note: Code is released under the GNU LGPL 9 * 10 * Copyright (C) 2001 Caldera International, Inc. 11 * 12 * This library is free software; you can redistribute it and/or 13 * modify it under the terms of the GNU Lesser General Public 14 * License as published by the Free Software Foundation; either 15 * version 2 of the License, or (at your option) any later version. 16 * 17 * This library is distributed in the hope that it will be useful, 18 * but WITHOUT ANY WARRANTY; without even the implied warranty of 19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 20 * Lesser General Public License for more details. 21 * 22 * You should have received a copy of the GNU Lesser General Public 23 * License along with this library; if not, write to: 24 * Free Software Foundation, Inc. 25 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 26 */ 27 28 /* #include "synonyms.h" */ 29 #include "re.h" 30 31 /* #pragma weak regcomp = _regcomp */ 32 33 int 34 regcomp(regex_t *ep, const char *pat, int flags) 35 { 36 Tree *tp; 37 Lex lex; 38 39 if ((tp=libuxre_regparse(&lex, (const unsigned char *)pat, flags)) == 0) 40 goto out; 41 ep->re_nsub = lex.nleft; 42 ep->re_flags = lex.flags & ~(REG_NOTBOL | REG_NOTEOL | REG_NONEMPTY); 43 ep->re_col = lex.col; 44 ep->re_mb_cur_max = lex.mb_cur_max; 45 /* 46 * Build the engine(s). The factors determining which are built: 47 * 1. If the pattern built insists on an NFA, then only build NFA. 48 * 2. If flags include REG_NOSUB or REG_ONESUB and not (1), 49 * then only build DFA. 50 * 3. Otherwise, build both. 51 * Since libuxre_regdfacomp() modifies the tree and libuxre_regnfacomp() 52 * doesn't, libuxre_regnfacomp() must be called first, if both are to 53 * be called. 54 */ 55 if (ep->re_nsub != 0 && (flags & (REG_NOSUB | REG_ONESUB)) == 0 56 || lex.flags & REG_NFA) 57 { 58 ep->re_flags |= REG_NFA; 59 if ((lex.err = libuxre_regnfacomp(ep, tp, &lex)) != 0) 60 goto out; 61 } 62 if ((lex.flags & REG_NFA) == 0) 63 { 64 ep->re_flags |= REG_DFA; 65 if ((lex.err = libuxre_regdfacomp(ep, tp, &lex)) != 0) 66 { 67 if (ep->re_flags & REG_NFA) 68 libuxre_regdelnfa(ep->re_nfa); 69 } 70 } 71 out:; 72 if (lex.err != 0 && lex.col != 0) 73 (void)libuxre_lc_collate(lex.col); 74 if (tp != 0) 75 libuxre_regdeltree(tp, lex.err); 76 return lex.err; 77 }