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Diffstat (limited to 'libraries/liblunicode/ure/ure.c')
-rw-r--r-- | libraries/liblunicode/ure/ure.c | 2131 |
1 files changed, 2131 insertions, 0 deletions
diff --git a/libraries/liblunicode/ure/ure.c b/libraries/liblunicode/ure/ure.c new file mode 100644 index 0000000..d91d01a --- /dev/null +++ b/libraries/liblunicode/ure/ure.c @@ -0,0 +1,2131 @@ +/* $OpenLDAP$ */ +/* This work is part of OpenLDAP Software <http://www.openldap.org/>. + * + * Copyright 1998-2018 The OpenLDAP Foundation. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted only as authorized by the OpenLDAP + * Public License. + * + * A copy of this license is available in file LICENSE in the + * top-level directory of the distribution or, alternatively, at + * <http://www.OpenLDAP.org/license.html>. + */ +/* Copyright 1997, 1998, 1999 Computing Research Labs, + * New Mexico State University + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE COMPUTING RESEARCH LAB OR NEW MEXICO STATE UNIVERSITY BE LIABLE FOR ANY + * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT + * OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR + * THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ +/* $Id: ure.c,v 1.2 1999/09/21 15:47:43 mleisher Exp $" */ + +#include "portable.h" + +#include <ac/stdlib.h> +#include <ac/string.h> +#include <ac/unistd.h> + +#include "ure.h" + +/* + * Flags used internally in the DFA. + */ +#define _URE_DFA_CASEFOLD 0x01 +#define _URE_DFA_BLANKLINE 0x02 + +static unsigned long cclass_flags[] = { + 0, + _URE_NONSPACING, + _URE_COMBINING, + _URE_NUMDIGIT, + _URE_NUMOTHER, + _URE_SPACESEP, + _URE_LINESEP, + _URE_PARASEP, + _URE_CNTRL, + _URE_PUA, + _URE_UPPER, + _URE_LOWER, + _URE_TITLE, + _URE_MODIFIER, + _URE_OTHERLETTER, + _URE_DASHPUNCT, + _URE_OPENPUNCT, + _URE_CLOSEPUNCT, + _URE_OTHERPUNCT, + _URE_MATHSYM, + _URE_CURRENCYSYM, + _URE_OTHERSYM, + _URE_LTR, + _URE_RTL, + _URE_EURONUM, + _URE_EURONUMSEP, + _URE_EURONUMTERM, + _URE_ARABNUM, + _URE_COMMONSEP, + _URE_BLOCKSEP, + _URE_SEGMENTSEP, + _URE_WHITESPACE, + _URE_OTHERNEUT, +}; + +/* + * Symbol types for the DFA. + */ +#define _URE_ANY_CHAR 1 +#define _URE_CHAR 2 +#define _URE_CCLASS 3 +#define _URE_NCCLASS 4 +#define _URE_BOL_ANCHOR 5 +#define _URE_EOL_ANCHOR 6 + +/* + * Op codes for converting the NFA to a DFA. + */ +#define _URE_SYMBOL 10 +#define _URE_PAREN 11 +#define _URE_QUEST 12 +#define _URE_STAR 13 +#define _URE_PLUS 14 +#define _URE_ONE 15 +#define _URE_AND 16 +#define _URE_OR 17 + +#define _URE_NOOP 0xffff + +#define _URE_REGSTART 0x8000 +#define _URE_REGEND 0x4000 + +/* + * Structure used to handle a compacted range of characters. + */ +typedef struct { + ucs4_t min_code; + ucs4_t max_code; +} _ure_range_t; + +typedef struct { + _ure_range_t *ranges; + ucs2_t ranges_used; + ucs2_t ranges_size; +} _ure_ccl_t; + +typedef union { + ucs4_t chr; + _ure_ccl_t ccl; +} _ure_sym_t; + +/* + * This is a general element structure used for expressions and stack + * elements. + */ +typedef struct { + ucs2_t reg; + ucs2_t onstack; + ucs2_t type; + ucs2_t lhs; + ucs2_t rhs; +} _ure_elt_t; + +/* + * This is a structure used to track a list or a stack of states. + */ +typedef struct { + ucs2_t *slist; + ucs2_t slist_size; + ucs2_t slist_used; +} _ure_stlist_t; + +/* + * Structure to track the list of unique states for a symbol + * during reduction. + */ +typedef struct { + ucs2_t id; + ucs2_t type; + unsigned long mods; + unsigned long props; + _ure_sym_t sym; + _ure_stlist_t states; +} _ure_symtab_t; + +/* + * Structure to hold a single state. + */ +typedef struct { + ucs2_t id; + ucs2_t accepting; + ucs2_t pad; + _ure_stlist_t st; + _ure_elt_t *trans; + ucs2_t trans_size; + ucs2_t trans_used; +} _ure_state_t; + +/* + * Structure used for keeping lists of states. + */ +typedef struct { + _ure_state_t *states; + ucs2_t states_size; + ucs2_t states_used; +} _ure_statetable_t; + +/* + * Structure to track pairs of DFA states when equivalent states are + * merged. + */ +typedef struct { + ucs2_t l; + ucs2_t r; +} _ure_equiv_t; + +/* + * Structure used for constructing the NFA and reducing to a minimal DFA. + */ +typedef struct _ure_buffer_t { + int reducing; + int error; + unsigned long flags; + + _ure_stlist_t stack; + + /* + * Table of unique symbols encountered. + */ + _ure_symtab_t *symtab; + ucs2_t symtab_size; + ucs2_t symtab_used; + + /* + * Tracks the unique expressions generated for the NFA and when the NFA is + * reduced. + */ + _ure_elt_t *expr; + ucs2_t expr_used; + ucs2_t expr_size; + + /* + * The reduced table of unique groups of NFA states. + */ + _ure_statetable_t states; + + /* + * Tracks states when equivalent states are merged. + */ + _ure_equiv_t *equiv; + ucs2_t equiv_used; + ucs2_t equiv_size; +} _ure_buffer_t; + +typedef struct { + ucs2_t symbol; + ucs2_t next_state; +} _ure_trans_t; + +typedef struct { + ucs2_t accepting; + ucs2_t ntrans; + _ure_trans_t *trans; +} _ure_dstate_t; + +typedef struct _ure_dfa_t { + unsigned long flags; + + _ure_symtab_t *syms; + ucs2_t nsyms; + + _ure_dstate_t *states; + ucs2_t nstates; + + _ure_trans_t *trans; + ucs2_t ntrans; +} _ure_dfa_t; + +/************************************************************************* + * + * Functions. + * + *************************************************************************/ + +static void +_ure_memmove(char *dest, char *src, unsigned long bytes) +{ + long i, j; + + i = (long) bytes; + j = i & 7; + i = (i + 7) >> 3; + + /* + * Do a memmove using Ye Olde Duff's Device for efficiency. + */ + if (src < dest) { + src += bytes; + dest += bytes; + + switch (j) { + case 0: do { + *--dest = *--src; + case 7: *--dest = *--src; + case 6: *--dest = *--src; + case 5: *--dest = *--src; + case 4: *--dest = *--src; + case 3: *--dest = *--src; + case 2: *--dest = *--src; + case 1: *--dest = *--src; + } while (--i > 0); + } + } else if (src > dest) { + switch (j) { + case 0: do { + *dest++ = *src++; + case 7: *dest++ = *src++; + case 6: *dest++ = *src++; + case 5: *dest++ = *src++; + case 4: *dest++ = *src++; + case 3: *dest++ = *src++; + case 2: *dest++ = *src++; + case 1: *dest++ = *src++; + } while (--i > 0); + } + } +} + +static void +_ure_push(ucs2_t v, _ure_buffer_t *b) +{ + _ure_stlist_t *s; + + if (b == 0) + return; + + /* + * If the `reducing' parameter is non-zero, check to see if the value + * passed is already on the stack. + */ + if (b->reducing != 0 && b->expr[v].onstack != 0) + return; + + s = &b->stack; + if (s->slist_used == s->slist_size) { + if (s->slist_size == 0) + s->slist = (ucs2_t *) malloc(sizeof(ucs2_t) << 3); + else + s->slist = (ucs2_t *) realloc((char *) s->slist, + sizeof(ucs2_t) * (s->slist_size + 8)); + s->slist_size += 8; + } + s->slist[s->slist_used++] = v; + + /* + * If the `reducing' parameter is non-zero, flag the element as being on + * the stack. + */ + if (b->reducing != 0) + b->expr[v].onstack = 1; +} + +static ucs2_t +_ure_peek(_ure_buffer_t *b) +{ + if (b == 0 || b->stack.slist_used == 0) + return _URE_NOOP; + + return b->stack.slist[b->stack.slist_used - 1]; +} + +static ucs2_t +_ure_pop(_ure_buffer_t *b) +{ + ucs2_t v; + + if (b == 0 || b->stack.slist_used == 0) + return _URE_NOOP; + + v = b->stack.slist[--b->stack.slist_used]; + if (b->reducing) + b->expr[v].onstack = 0; + + return v; +} + +/************************************************************************* + * + * Start symbol parse functions. + * + *************************************************************************/ + +/* + * Parse a comma-separated list of integers that represent character + * properties. Combine them into a mask that is returned in the `mask' + * variable, and return the number of characters consumed. + */ +static unsigned long +_ure_prop_list(ucs2_t *pp, unsigned long limit, unsigned long *mask, + _ure_buffer_t *b) +{ + unsigned long n, m; + ucs2_t *sp, *ep; + + sp = pp; + ep = sp + limit; + + for (m = n = 0; b->error == _URE_OK && sp < ep; sp++) { + if (*sp == ',') { + /* + * Encountered a comma, so select the next character property flag + * and reset the number. + */ + m |= cclass_flags[n]; + n = 0; + } else if (*sp >= '0' && *sp <= '9') + /* + * Encountered a digit, so start or continue building the cardinal + * that represents the character property flag. + */ + n = (n * 10) + (*sp - '0'); + else + /* + * Encountered something that is not part of the property list. + * Indicate that we are done. + */ + break; + + /* + * If a property number greater than 32 occurs, then there is a + * problem. Most likely a missing comma separator. + */ + if (n > 32) + b->error = _URE_INVALID_PROPERTY; + } + + if (b->error == _URE_OK && n != 0) + m |= cclass_flags[n]; + + /* + * Set the mask that represents the group of character properties. + */ + *mask = m; + + /* + * Return the number of characters consumed. + */ + return sp - pp; +} + +/* + * Collect a hex number with 1 to 4 digits and return the number + * of characters used. + */ +static unsigned long +_ure_hex(ucs2_t *np, unsigned long limit, ucs4_t *n) +{ + ucs2_t i; + ucs2_t *sp, *ep; + ucs4_t nn; + + sp = np; + ep = sp + limit; + + for (nn = 0, i = 0; i < 4 && sp < ep; i++, sp++) { + if (*sp >= '0' && *sp <= '9') + nn = (nn << 4) + (*sp - '0'); + else if (*sp >= 'A' && *sp <= 'F') + nn = (nn << 4) + ((*sp - 'A') + 10); + else if (*sp >= 'a' && *sp <= 'f') + nn = (nn << 4) + ((*sp - 'a') + 10); + else + /* + * Encountered something that is not a hex digit. + */ + break; + } + + /* + * Assign the character code collected and return the number of + * characters used. + */ + *n = nn; + + return sp - np; +} + +/* + * Insert a range into a character class, removing duplicates and ordering + * them in increasing range-start order. + */ +static void +_ure_add_range(_ure_ccl_t *ccl, _ure_range_t *r, _ure_buffer_t *b) +{ + ucs2_t i; + ucs4_t tmp; + _ure_range_t *rp; + + /* + * If the `casefold' flag is set, then make sure both endpoints of the + * range are converted to lower case. + */ + if (b->flags & _URE_DFA_CASEFOLD) { + r->min_code = _ure_tolower(r->min_code); + r->max_code = _ure_tolower(r->max_code); + } + + /* + * Swap the range endpoints if they are not in increasing order. + */ + if (r->min_code > r->max_code) { + tmp = r->min_code; + r->min_code = r->max_code; + r->max_code = tmp; + } + + for (i = 0, rp = ccl->ranges; + i < ccl->ranges_used && r->min_code < rp->min_code; i++, rp++) ; + + /* + * Check for a duplicate. + */ + if (i < ccl->ranges_used && + r->min_code == rp->min_code && r->max_code == rp->max_code) + return; + + if (ccl->ranges_used == ccl->ranges_size) { + if (ccl->ranges_size == 0) + ccl->ranges = (_ure_range_t *) malloc(sizeof(_ure_range_t) << 3); + else + ccl->ranges = (_ure_range_t *) + realloc((char *) ccl->ranges, + sizeof(_ure_range_t) * (ccl->ranges_size + 8)); + ccl->ranges_size += 8; + } + + rp = ccl->ranges + ccl->ranges_used; + + if (i < ccl->ranges_used) + _ure_memmove((char *) (rp + 1), (char *) rp, + sizeof(_ure_range_t) * (ccl->ranges_used - i)); + + ccl->ranges_used++; + rp->min_code = r->min_code; + rp->max_code = r->max_code; +} + +#define _URE_ALPHA_MASK (_URE_UPPER|_URE_LOWER|_URE_OTHERLETTER|\ +_URE_MODIFIER|_URE_TITLE|_URE_NONSPACING|_URE_COMBINING) +#define _URE_ALNUM_MASK (_URE_ALPHA_MASK|_URE_NUMDIGIT) +#define _URE_PUNCT_MASK (_URE_DASHPUNCT|_URE_OPENPUNCT|_URE_CLOSEPUNCT|\ +_URE_OTHERPUNCT) +#define _URE_GRAPH_MASK (_URE_NUMDIGIT|_URE_NUMOTHER|_URE_ALPHA_MASK|\ +_URE_MATHSYM|_URE_CURRENCYSYM|_URE_OTHERSYM) +#define _URE_PRINT_MASK (_URE_GRAPH_MASK|_URE_SPACESEP) +#define _URE_SPACE_MASK (_URE_SPACESEP|_URE_LINESEP|_URE_PARASEP) + +typedef void (*_ure_cclsetup_t)( + _ure_symtab_t *sym, + unsigned long mask, + _ure_buffer_t *b +); + +typedef struct { + ucs2_t key; + unsigned long len; + unsigned long next; + _ure_cclsetup_t func; + unsigned long mask; +} _ure_trie_t; + +static void +_ure_ccl_setup(_ure_symtab_t *sym, unsigned long mask, _ure_buffer_t *b) +{ + sym->props |= mask; +} + +static void +_ure_space_setup(_ure_symtab_t *sym, unsigned long mask, _ure_buffer_t *b) +{ + _ure_range_t range; + + sym->props |= mask; + + /* + * Add the additional characters needed for handling isspace(). + */ + range.min_code = range.max_code = '\t'; + _ure_add_range(&sym->sym.ccl, &range, b); + range.min_code = range.max_code = '\r'; + _ure_add_range(&sym->sym.ccl, &range, b); + range.min_code = range.max_code = '\n'; + _ure_add_range(&sym->sym.ccl, &range, b); + range.min_code = range.max_code = '\f'; + _ure_add_range(&sym->sym.ccl, &range, b); + range.min_code = range.max_code = 0xfeff; + _ure_add_range(&sym->sym.ccl, &range, b); +} + +static void +_ure_xdigit_setup(_ure_symtab_t *sym, unsigned long mask, _ure_buffer_t *b) +{ + _ure_range_t range; + + /* + * Add the additional characters needed for handling isxdigit(). + */ + range.min_code = '0'; + range.max_code = '9'; + _ure_add_range(&sym->sym.ccl, &range, b); + range.min_code = 'A'; + range.max_code = 'F'; + _ure_add_range(&sym->sym.ccl, &range, b); + range.min_code = 'a'; + range.max_code = 'f'; + _ure_add_range(&sym->sym.ccl, &range, b); +} + +static _ure_trie_t cclass_trie[] = { + {0x003a, 1, 1, 0, 0}, + {0x0061, 9, 10, 0, 0}, + {0x0063, 8, 19, 0, 0}, + {0x0064, 7, 24, 0, 0}, + {0x0067, 6, 29, 0, 0}, + {0x006c, 5, 34, 0, 0}, + {0x0070, 4, 39, 0, 0}, + {0x0073, 3, 49, 0, 0}, + {0x0075, 2, 54, 0, 0}, + {0x0078, 1, 59, 0, 0}, + {0x006c, 1, 11, 0, 0}, + {0x006e, 2, 13, 0, 0}, + {0x0070, 1, 16, 0, 0}, + {0x0075, 1, 14, 0, 0}, + {0x006d, 1, 15, 0, 0}, + {0x003a, 1, 16, _ure_ccl_setup, _URE_ALNUM_MASK}, + {0x0068, 1, 17, 0, 0}, + {0x0061, 1, 18, 0, 0}, + {0x003a, 1, 19, _ure_ccl_setup, _URE_ALPHA_MASK}, + {0x006e, 1, 20, 0, 0}, + {0x0074, 1, 21, 0, 0}, + {0x0072, 1, 22, 0, 0}, + {0x006c, 1, 23, 0, 0}, + {0x003a, 1, 24, _ure_ccl_setup, _URE_CNTRL}, + {0x0069, 1, 25, 0, 0}, + {0x0067, 1, 26, 0, 0}, + {0x0069, 1, 27, 0, 0}, + {0x0074, 1, 28, 0, 0}, + {0x003a, 1, 29, _ure_ccl_setup, _URE_NUMDIGIT}, + {0x0072, 1, 30, 0, 0}, + {0x0061, 1, 31, 0, 0}, + {0x0070, 1, 32, 0, 0}, + {0x0068, 1, 33, 0, 0}, + {0x003a, 1, 34, _ure_ccl_setup, _URE_GRAPH_MASK}, + {0x006f, 1, 35, 0, 0}, + {0x0077, 1, 36, 0, 0}, + {0x0065, 1, 37, 0, 0}, + {0x0072, 1, 38, 0, 0}, + {0x003a, 1, 39, _ure_ccl_setup, _URE_LOWER}, + {0x0072, 2, 41, 0, 0}, + {0x0075, 1, 45, 0, 0}, + {0x0069, 1, 42, 0, 0}, + {0x006e, 1, 43, 0, 0}, + {0x0074, 1, 44, 0, 0}, + {0x003a, 1, 45, _ure_ccl_setup, _URE_PRINT_MASK}, + {0x006e, 1, 46, 0, 0}, + {0x0063, 1, 47, 0, 0}, + {0x0074, 1, 48, 0, 0}, + {0x003a, 1, 49, _ure_ccl_setup, _URE_PUNCT_MASK}, + {0x0070, 1, 50, 0, 0}, + {0x0061, 1, 51, 0, 0}, + {0x0063, 1, 52, 0, 0}, + {0x0065, 1, 53, 0, 0}, + {0x003a, 1, 54, _ure_space_setup, _URE_SPACE_MASK}, + {0x0070, 1, 55, 0, 0}, + {0x0070, 1, 56, 0, 0}, + {0x0065, 1, 57, 0, 0}, + {0x0072, 1, 58, 0, 0}, + {0x003a, 1, 59, _ure_ccl_setup, _URE_UPPER}, + {0x0064, 1, 60, 0, 0}, + {0x0069, 1, 61, 0, 0}, + {0x0067, 1, 62, 0, 0}, + {0x0069, 1, 63, 0, 0}, + {0x0074, 1, 64, 0, 0}, + {0x003a, 1, 65, _ure_xdigit_setup, 0}, +}; + +/* + * Probe for one of the POSIX colon delimited character classes in the static + * trie. + */ +static unsigned long +_ure_posix_ccl(ucs2_t *cp, unsigned long limit, _ure_symtab_t *sym, + _ure_buffer_t *b) +{ + int i; + unsigned long n; + _ure_trie_t *tp; + ucs2_t *sp, *ep; + + /* + * If the number of characters left is less than 7, then this cannot be + * interpreted as one of the colon delimited classes. + */ + if (limit < 7) + return 0; + + sp = cp; + ep = sp + limit; + tp = cclass_trie; + for (i = 0; sp < ep && i < 8; i++, sp++) { + n = tp->len; + + for (; n > 0 && tp->key != *sp; tp++, n--) ; + + if (n == 0) + return 0; + + if (*sp == ':' && (i == 6 || i == 7)) { + sp++; + break; + } + if (sp + 1 < ep) + tp = cclass_trie + tp->next; + } + if (tp->func == 0) + return 0; + + (*tp->func)(sym, tp->mask, b); + + return sp - cp; +} + +/* + * Construct a list of ranges and return the number of characters consumed. + */ +static unsigned long +_ure_cclass(ucs2_t *cp, unsigned long limit, _ure_symtab_t *symp, + _ure_buffer_t *b) +{ + int range_end; + unsigned long n; + ucs2_t *sp, *ep; + ucs4_t c, last; + _ure_ccl_t *cclp; + _ure_range_t range; + + sp = cp; + ep = sp + limit; + + if (*sp == '^') { + symp->type = _URE_NCCLASS; + sp++; + } else + symp->type = _URE_CCLASS; + + for (last = 0, range_end = 0; + b->error == _URE_OK && sp < ep && *sp != ']'; ) { + c = *sp++; + if (c == '\\') { + if (sp == ep) { + /* + * The EOS was encountered when expecting the reverse solidus + * to be followed by the character it is escaping. Set an + * error code and return the number of characters consumed up + * to this point. + */ + b->error = _URE_UNEXPECTED_EOS; + return sp - cp; + } + + c = *sp++; + switch (c) { + case 'a': + c = 0x07; + break; + case 'b': + c = 0x08; + break; + case 'f': + c = 0x0c; + break; + case 'n': + c = 0x0a; + break; + case 'r': + c = 0x0d; + break; + case 't': + c = 0x09; + break; + case 'v': + c = 0x0b; + break; + case 'p': + case 'P': + sp += _ure_prop_list(sp, ep - sp, &symp->props, b); + /* + * Invert the bit mask of the properties if this is a negated + * character class or if 'P' is used to specify a list of + * character properties that should *not* match in a + * character class. + */ + if (c == 'P') + symp->props = ~symp->props; + continue; + break; + case 'x': + case 'X': + case 'u': + case 'U': + if (sp < ep && + ((*sp >= '0' && *sp <= '9') || + (*sp >= 'A' && *sp <= 'F') || + (*sp >= 'a' && *sp <= 'f'))) + sp += _ure_hex(sp, ep - sp, &c); + } + } else if (c == ':') { + /* + * Probe for a POSIX colon delimited character class. + */ + sp--; + if ((n = _ure_posix_ccl(sp, ep - sp, symp, b)) == 0) + sp++; + else { + sp += n; + continue; + } + } + + cclp = &symp->sym.ccl; + + /* + * Check to see if the current character is a low surrogate that needs + * to be combined with a preceding high surrogate. + */ + if (last != 0) { + if (c >= 0xdc00 && c <= 0xdfff) + /* + * Construct the UTF16 character code. + */ + c = 0x10000 + (((last & 0x03ff) << 10) | (c & 0x03ff)); + else { + /* + * Add the isolated high surrogate to the range. + */ + if (range_end == 1) + range.max_code = last & 0xffff; + else + range.min_code = range.max_code = last & 0xffff; + + _ure_add_range(cclp, &range, b); + range_end = 0; + } + } + + /* + * Clear the last character code. + */ + last = 0; + + /* + * This slightly awkward code handles the different cases needed to + * construct a range. + */ + if (c >= 0xd800 && c <= 0xdbff) { + /* + * If the high surrogate is followed by a range indicator, simply + * add it as the range start. Otherwise, save it in case the next + * character is a low surrogate. + */ + if (*sp == '-') { + sp++; + range.min_code = c; + range_end = 1; + } else + last = c; + } else if (range_end == 1) { + range.max_code = c; + _ure_add_range(cclp, &range, b); + range_end = 0; + } else { + range.min_code = range.max_code = c; + if (*sp == '-') { + sp++; + range_end = 1; + } else + _ure_add_range(cclp, &range, b); + } + } + + if (sp < ep && *sp == ']') + sp++; + else + /* + * The parse was not terminated by the character class close symbol + * (']'), so set an error code. + */ + b->error = _URE_CCLASS_OPEN; + + return sp - cp; +} + +/* + * Probe for a low surrogate hex code. + */ +static unsigned long +_ure_probe_ls(ucs2_t *ls, unsigned long limit, ucs4_t *c) +{ + ucs4_t i, code; + ucs2_t *sp, *ep; + + for (i = code = 0, sp = ls, ep = sp + limit; i < 4 && sp < ep; sp++) { + if (*sp >= '0' && *sp <= '9') + code = (code << 4) + (*sp - '0'); + else if (*sp >= 'A' && *sp <= 'F') + code = (code << 4) + ((*sp - 'A') + 10); + else if (*sp >= 'a' && *sp <= 'f') + code = (code << 4) + ((*sp - 'a') + 10); + else + break; + } + + *c = code; + return (0xdc00 <= code && code <= 0xdfff) ? sp - ls : 0; +} + +static unsigned long +_ure_compile_symbol(ucs2_t *sym, unsigned long limit, _ure_symtab_t *symp, + _ure_buffer_t *b) +{ + ucs4_t c; + ucs2_t *sp, *ep; + + sp = sym; + ep = sym + limit; + + if ((c = *sp++) == '\\') { + + if (sp == ep) { + /* + * The EOS was encountered when expecting the reverse solidus to + * be followed by the character it is escaping. Set an error code + * and return the number of characters consumed up to this point. + */ + b->error = _URE_UNEXPECTED_EOS; + return sp - sym; + } + + c = *sp++; + switch (c) { + case 'p': + case 'P': + symp->type = (c == 'p') ? _URE_CCLASS : _URE_NCCLASS; + sp += _ure_prop_list(sp, ep - sp, &symp->props, b); + break; + case 'a': + symp->type = _URE_CHAR; + symp->sym.chr = 0x07; + break; + case 'b': + symp->type = _URE_CHAR; + symp->sym.chr = 0x08; + break; + case 'f': + symp->type = _URE_CHAR; + symp->sym.chr = 0x0c; + break; + case 'n': + symp->type = _URE_CHAR; + symp->sym.chr = 0x0a; + break; + case 'r': + symp->type = _URE_CHAR; + symp->sym.chr = 0x0d; + break; + case 't': + symp->type = _URE_CHAR; + symp->sym.chr = 0x09; + break; + case 'v': + symp->type = _URE_CHAR; + symp->sym.chr = 0x0b; + break; + case 'x': + case 'X': + case 'u': + case 'U': + /* + * Collect between 1 and 4 digits representing a UCS2 code. Fall + * through to the next case. + */ + if (sp < ep && + ((*sp >= '0' && *sp <= '9') || + (*sp >= 'A' && *sp <= 'F') || + (*sp >= 'a' && *sp <= 'f'))) + sp += _ure_hex(sp, ep - sp, &c); + /* FALLTHROUGH */ + default: + /* + * Simply add an escaped character here. + */ + symp->type = _URE_CHAR; + symp->sym.chr = c; + } + } else if (c == '^' || c == '$') + /* + * Handle the BOL and EOL anchors. This actually consists simply of + * setting a flag that indicates that the user supplied anchor match + * function should be called. This needs to be done instead of simply + * matching line/paragraph separators because beginning-of-text and + * end-of-text tests are needed as well. + */ + symp->type = (c == '^') ? _URE_BOL_ANCHOR : _URE_EOL_ANCHOR; + else if (c == '[') + /* + * Construct a character class. + */ + sp += _ure_cclass(sp, ep - sp, symp, b); + else if (c == '.') + symp->type = _URE_ANY_CHAR; + else { + symp->type = _URE_CHAR; + symp->sym.chr = c; + } + + /* + * If the symbol type happens to be a character and is a high surrogate, + * then probe forward to see if it is followed by a low surrogate that + * needs to be added. + */ + if (sp < ep && symp->type == _URE_CHAR && + 0xd800 <= symp->sym.chr && symp->sym.chr <= 0xdbff) { + + if (0xdc00 <= *sp && *sp <= 0xdfff) { + symp->sym.chr = 0x10000 + (((symp->sym.chr & 0x03ff) << 10) | + (*sp & 0x03ff)); + sp++; + } else if (*sp == '\\' && (*(sp + 1) == 'x' || *(sp + 1) == 'X' || + *(sp + 1) == 'u' || *(sp + 1) == 'U')) { + sp += _ure_probe_ls(sp + 2, ep - (sp + 2), &c); + if (0xdc00 <= c && c <= 0xdfff) { + /* + * Take into account the \[xu] in front of the hex code. + */ + sp += 2; + symp->sym.chr = 0x10000 + (((symp->sym.chr & 0x03ff) << 10) | + (c & 0x03ff)); + } + } + } + + /* + * Last, make sure any _URE_CHAR type symbols are changed to lower case if + * the `casefold' flag is set. + */ + if ((b->flags & _URE_DFA_CASEFOLD) && symp->type == _URE_CHAR) + symp->sym.chr = _ure_tolower(symp->sym.chr); + + /* + * If the symbol constructed is anything other than one of the anchors, + * make sure the _URE_DFA_BLANKLINE flag is removed. + */ + if (symp->type != _URE_BOL_ANCHOR && symp->type != _URE_EOL_ANCHOR) + b->flags &= ~_URE_DFA_BLANKLINE; + + /* + * Return the number of characters consumed. + */ + return sp - sym; +} + +static int +_ure_sym_neq(_ure_symtab_t *a, _ure_symtab_t *b) +{ + if (a->type != b->type || a->mods != b->mods || a->props != b->props) + return 1; + + if (a->type == _URE_CCLASS || a->type == _URE_NCCLASS) { + if (a->sym.ccl.ranges_used != b->sym.ccl.ranges_used) + return 1; + if (a->sym.ccl.ranges_used > 0 && + memcmp((char *) a->sym.ccl.ranges, (char *) b->sym.ccl.ranges, + sizeof(_ure_range_t) * a->sym.ccl.ranges_used) != 0) + return 1; + } else if (a->type == _URE_CHAR && a->sym.chr != b->sym.chr) + return 1; + return 0; +} + +/* + * Construct a symbol, but only keep unique symbols. + */ +static ucs2_t +_ure_make_symbol(ucs2_t *sym, unsigned long limit, unsigned long *consumed, + _ure_buffer_t *b) +{ + ucs2_t i; + _ure_symtab_t *sp, symbol; + + /* + * Build the next symbol so we can test to see if it is already in the + * symbol table. + */ + (void) memset((char *) &symbol, '\0', sizeof(_ure_symtab_t)); + *consumed = _ure_compile_symbol(sym, limit, &symbol, b); + + /* + * Check to see if the symbol exists. + */ + for (i = 0, sp = b->symtab; + i < b->symtab_used && _ure_sym_neq(&symbol, sp); i++, sp++) ; + + if (i < b->symtab_used) { + /* + * Free up any ranges used for the symbol. + */ + if ((symbol.type == _URE_CCLASS || symbol.type == _URE_NCCLASS) && + symbol.sym.ccl.ranges_size > 0) + free((char *) symbol.sym.ccl.ranges); + + return b->symtab[i].id; + } + + /* + * Need to add the new symbol. + */ + if (b->symtab_used == b->symtab_size) { + if (b->symtab_size == 0) + b->symtab = (_ure_symtab_t *) malloc(sizeof(_ure_symtab_t) << 3); + else + b->symtab = (_ure_symtab_t *) + realloc((char *) b->symtab, + sizeof(_ure_symtab_t) * (b->symtab_size + 8)); + sp = b->symtab + b->symtab_size; + (void) memset((char *) sp, '\0', sizeof(_ure_symtab_t) << 3); + b->symtab_size += 8; + } + + symbol.id = b->symtab_used++; + (void) AC_MEMCPY((char *) &b->symtab[symbol.id], (char *) &symbol, + sizeof(_ure_symtab_t)); + + return symbol.id; +} + +/************************************************************************* + * + * End symbol parse functions. + * + *************************************************************************/ + +static ucs2_t +_ure_make_expr(ucs2_t type, ucs2_t lhs, ucs2_t rhs, _ure_buffer_t *b) +{ + ucs2_t i; + + if (b == 0) + return _URE_NOOP; + + /* + * Determine if the expression already exists or not. + */ + for (i = 0; i < b->expr_used; i++) { + if (b->expr[i].type == type && b->expr[i].lhs == lhs && + b->expr[i].rhs == rhs) + break; + } + if (i < b->expr_used) + return i; + + /* + * Need to add a new expression. + */ + if (b->expr_used == b->expr_size) { + if (b->expr_size == 0) + b->expr = (_ure_elt_t *) malloc(sizeof(_ure_elt_t) << 3); + else + b->expr = (_ure_elt_t *) + realloc((char *) b->expr, + sizeof(_ure_elt_t) * (b->expr_size + 8)); + b->expr_size += 8; + } + + b->expr[b->expr_used].onstack = 0; + b->expr[b->expr_used].type = type; + b->expr[b->expr_used].lhs = lhs; + b->expr[b->expr_used].rhs = rhs; + + return b->expr_used++; +} + +static unsigned char spmap[] = { + 0x00, 0x00, 0x00, 0x00, 0x00, 0x0f, 0x00, 0x80, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, +}; + +#define _ure_isspecial(cc) ((cc) > 0x20 && (cc) < 0x7f && \ + (spmap[(cc) >> 3] & (1 << ((cc) & 7)))) + +/* + * Convert the regular expression into an NFA in a form that will be easy to + * reduce to a DFA. The starting state for the reduction will be returned. + */ +static ucs2_t +_ure_re2nfa(ucs2_t *re, unsigned long relen, _ure_buffer_t *b) +{ + ucs2_t c, state, top, sym, *sp, *ep; + unsigned long used; + + state = _URE_NOOP; + + sp = re; + ep = sp + relen; + while (b->error == _URE_OK && sp < ep) { + c = *sp++; + switch (c) { + case '(': + _ure_push(_URE_PAREN, b); + break; + case ')': + /* + * Check for the case of too many close parentheses. + */ + if (_ure_peek(b) == _URE_NOOP) { + b->error = _URE_UNBALANCED_GROUP; + break; + } + + while ((top = _ure_peek(b)) == _URE_AND || top == _URE_OR) + /* + * Make an expression with the AND or OR operator and its right + * hand side. + */ + state = _ure_make_expr(_ure_pop(b), _ure_pop(b), state, b); + + /* + * Remove the _URE_PAREN off the stack. + */ + (void) _ure_pop(b); + break; + case '*': + state = _ure_make_expr(_URE_STAR, state, _URE_NOOP, b); + break; + case '+': + state = _ure_make_expr(_URE_PLUS, state, _URE_NOOP, b); + break; + case '?': + state = _ure_make_expr(_URE_QUEST, state, _URE_NOOP, b); + break; + case '|': + while ((top = _ure_peek(b)) == _URE_AND || top == _URE_OR) + /* + * Make an expression with the AND or OR operator and its right + * hand side. + */ + state = _ure_make_expr(_ure_pop(b), _ure_pop(b), state, b); + + _ure_push(state, b); + _ure_push(_URE_OR, b); + break; + default: + sp--; + sym = _ure_make_symbol(sp, ep - sp, &used, b); + sp += used; + state = _ure_make_expr(_URE_SYMBOL, sym, _URE_NOOP, b); + break; + } + + if (c != '(' && c != '|' && sp < ep && + (!_ure_isspecial(*sp) || *sp == '(')) { + _ure_push(state, b); + _ure_push(_URE_AND, b); + } + } + while ((top = _ure_peek(b)) == _URE_AND || top == _URE_OR) + /* + * Make an expression with the AND or OR operator and its right + * hand side. + */ + state = _ure_make_expr(_ure_pop(b), _ure_pop(b), state, b); + + if (b->stack.slist_used > 0) + b->error = _URE_UNBALANCED_GROUP; + + return (b->error == _URE_OK) ? state : _URE_NOOP; +} + +static void +_ure_add_symstate(ucs2_t sym, ucs2_t state, _ure_buffer_t *b) +{ + ucs2_t i, *stp; + _ure_symtab_t *sp; + + /* + * Locate the symbol in the symbol table so the state can be added. + * If the symbol doesn't exist, then a real problem exists. + */ + for (i = 0, sp = b->symtab; i < b->symtab_used && sym != sp->id; + i++, sp++) ; + + /* + * Now find out if the state exists in the symbol's state list. + */ + for (i = 0, stp = sp->states.slist; + i < sp->states.slist_used && state > *stp; i++, stp++) ; + + if (i == sp->states.slist_used || state < *stp) { + /* + * Need to add the state in order. + */ + if (sp->states.slist_used == sp->states.slist_size) { + if (sp->states.slist_size == 0) + sp->states.slist = (ucs2_t *) malloc(sizeof(ucs2_t) << 3); + else + sp->states.slist = (ucs2_t *) + realloc((char *) sp->states.slist, + sizeof(ucs2_t) * (sp->states.slist_size + 8)); + sp->states.slist_size += 8; + } + if (i < sp->states.slist_used) + (void) _ure_memmove((char *) (sp->states.slist + i + 1), + (char *) (sp->states.slist + i), + sizeof(ucs2_t) * (sp->states.slist_used - i)); + sp->states.slist[i] = state; + sp->states.slist_used++; + } +} + +static ucs2_t +_ure_add_state(ucs2_t nstates, ucs2_t *states, _ure_buffer_t *b) +{ + ucs2_t i; + _ure_state_t *sp; + + for (i = 0, sp = b->states.states; i < b->states.states_used; i++, sp++) { + if (sp->st.slist_used == nstates && + memcmp((char *) states, (char *) sp->st.slist, + sizeof(ucs2_t) * nstates) == 0) + break; + } + + if (i == b->states.states_used) { + /* + * Need to add a new DFA state (set of NFA states). + */ + if (b->states.states_used == b->states.states_size) { + if (b->states.states_size == 0) + b->states.states = (_ure_state_t *) + malloc(sizeof(_ure_state_t) << 3); + else + b->states.states = (_ure_state_t *) + realloc((char *) b->states.states, + sizeof(_ure_state_t) * (b->states.states_size + 8)); + sp = b->states.states + b->states.states_size; + (void) memset((char *) sp, '\0', sizeof(_ure_state_t) << 3); + b->states.states_size += 8; + } + + sp = b->states.states + b->states.states_used++; + sp->id = i; + + if (sp->st.slist_used + nstates > sp->st.slist_size) { + if (sp->st.slist_size == 0) + sp->st.slist = (ucs2_t *) + malloc(sizeof(ucs2_t) * (sp->st.slist_used + nstates)); + else + sp->st.slist = (ucs2_t *) + realloc((char *) sp->st.slist, + sizeof(ucs2_t) * (sp->st.slist_used + nstates)); + sp->st.slist_size = sp->st.slist_used + nstates; + } + sp->st.slist_used = nstates; + (void) AC_MEMCPY((char *) sp->st.slist, (char *) states, + sizeof(ucs2_t) * nstates); + } + + /* + * Return the ID of the DFA state representing a group of NFA states. + */ + return i; +} + +static void +_ure_reduce(ucs2_t start, _ure_buffer_t *b) +{ + ucs2_t i, j, state, eval, syms, rhs; + ucs2_t s1, s2, ns1, ns2; + _ure_state_t *sp; + _ure_symtab_t *smp; + + b->reducing = 1; + + /* + * Add the starting state for the reduction. + */ + _ure_add_state(1, &start, b); + + /* + * Process each set of NFA states that get created. + */ + for (i = 0; i < b->states.states_used; i++) { + sp = b->states.states + i; + + /* + * Push the current states on the stack. + */ + for (j = 0; j < sp->st.slist_used; j++) + _ure_push(sp->st.slist[j], b); + + /* + * Reduce the NFA states. + */ + for (j = sp->accepting = syms = 0; j < b->stack.slist_used; j++) { + state = b->stack.slist[j]; + eval = 1; + + /* + * This inner loop is the iterative equivalent of recursively + * reducing subexpressions generated as a result of a reduction. + */ + while (eval) { + switch (b->expr[state].type) { + case _URE_SYMBOL: + ns1 = _ure_make_expr(_URE_ONE, _URE_NOOP, _URE_NOOP, b); + _ure_add_symstate(b->expr[state].lhs, ns1, b); + syms++; + eval = 0; + break; + case _URE_ONE: + sp->accepting = 1; + eval = 0; + break; + case _URE_QUEST: + s1 = b->expr[state].lhs; + ns1 = _ure_make_expr(_URE_ONE, _URE_NOOP, _URE_NOOP, b); + state = _ure_make_expr(_URE_OR, ns1, s1, b); + break; + case _URE_PLUS: + s1 = b->expr[state].lhs; + ns1 = _ure_make_expr(_URE_STAR, s1, _URE_NOOP, b); + state = _ure_make_expr(_URE_AND, s1, ns1, b); + break; + case _URE_STAR: + s1 = b->expr[state].lhs; + ns1 = _ure_make_expr(_URE_ONE, _URE_NOOP, _URE_NOOP, b); + ns2 = _ure_make_expr(_URE_PLUS, s1, _URE_NOOP, b); + state = _ure_make_expr(_URE_OR, ns1, ns2, b); + break; + case _URE_OR: + s1 = b->expr[state].lhs; + s2 = b->expr[state].rhs; + _ure_push(s1, b); + _ure_push(s2, b); + eval = 0; + break; + case _URE_AND: + s1 = b->expr[state].lhs; + s2 = b->expr[state].rhs; + switch (b->expr[s1].type) { + case _URE_SYMBOL: + _ure_add_symstate(b->expr[s1].lhs, s2, b); + syms++; + eval = 0; + break; + case _URE_ONE: + state = s2; + break; + case _URE_QUEST: + ns1 = b->expr[s1].lhs; + ns2 = _ure_make_expr(_URE_AND, ns1, s2, b); + state = _ure_make_expr(_URE_OR, s2, ns2, b); + break; + case _URE_PLUS: + ns1 = b->expr[s1].lhs; + ns2 = _ure_make_expr(_URE_OR, s2, state, b); + state = _ure_make_expr(_URE_AND, ns1, ns2, b); + break; + case _URE_STAR: + ns1 = b->expr[s1].lhs; + ns2 = _ure_make_expr(_URE_AND, ns1, state, b); + state = _ure_make_expr(_URE_OR, s2, ns2, b); + break; + case _URE_OR: + ns1 = b->expr[s1].lhs; + ns2 = b->expr[s1].rhs; + ns1 = _ure_make_expr(_URE_AND, ns1, s2, b); + ns2 = _ure_make_expr(_URE_AND, ns2, s2, b); + state = _ure_make_expr(_URE_OR, ns1, ns2, b); + break; + case _URE_AND: + ns1 = b->expr[s1].lhs; + ns2 = b->expr[s1].rhs; + ns2 = _ure_make_expr(_URE_AND, ns2, s2, b); + state = _ure_make_expr(_URE_AND, ns1, ns2, b); + break; + } + } + } + } + + /* + * Clear the state stack. + */ + while (_ure_pop(b) != _URE_NOOP) ; + + /* + * Reset the state pointer because the reduction may have moved it + * during a reallocation. + */ + sp = b->states.states + i; + + /* + * Generate the DFA states for the symbols collected during the + * current reduction. + */ + if (sp->trans_used + syms > sp->trans_size) { + if (sp->trans_size == 0) + sp->trans = (_ure_elt_t *) + malloc(sizeof(_ure_elt_t) * (sp->trans_used + syms)); + else + sp->trans = (_ure_elt_t *) + realloc((char *) sp->trans, + sizeof(_ure_elt_t) * (sp->trans_used + syms)); + sp->trans_size = sp->trans_used + syms; + } + + /* + * Go through the symbol table and generate the DFA state transitions + * for each symbol that has collected NFA states. + */ + for (j = syms = 0, smp = b->symtab; j < b->symtab_used; j++, smp++) { + sp = b->states.states + i; + + if (smp->states.slist_used > 0) { + sp->trans[syms].lhs = smp->id; + rhs = _ure_add_state(smp->states.slist_used, + smp->states.slist, b); + /* + * Reset the state pointer in case the reallocation moves it + * in memory. + */ + sp = b->states.states + i; + sp->trans[syms].rhs = rhs; + + smp->states.slist_used = 0; + syms++; + } + } + + /* + * Set the number of transitions actually used. + */ + sp->trans_used = syms; + } + b->reducing = 0; +} + +static void +_ure_add_equiv(ucs2_t l, ucs2_t r, _ure_buffer_t *b) +{ + ucs2_t tmp; + + l = b->states.states[l].id; + r = b->states.states[r].id; + + if (l == r) + return; + + if (l > r) { + tmp = l; + l = r; + r = tmp; + } + + /* + * Check to see if the equivalence pair already exists. + */ + for (tmp = 0; tmp < b->equiv_used && + (b->equiv[tmp].l != l || b->equiv[tmp].r != r); + tmp++) ; + + if (tmp < b->equiv_used) + return; + + if (b->equiv_used == b->equiv_size) { + if (b->equiv_size == 0) + b->equiv = (_ure_equiv_t *) malloc(sizeof(_ure_equiv_t) << 3); + else + b->equiv = (_ure_equiv_t *) realloc((char *) b->equiv, + sizeof(_ure_equiv_t) * + (b->equiv_size + 8)); + b->equiv_size += 8; + } + b->equiv[b->equiv_used].l = l; + b->equiv[b->equiv_used].r = r; + b->equiv_used++; +} + +/* + * Merge the DFA states that are equivalent. + */ +static void +_ure_merge_equiv(_ure_buffer_t *b) +{ + ucs2_t i, j, k, eq, done; + _ure_state_t *sp1, *sp2, *ls, *rs; + + for (i = 0; i < b->states.states_used; i++) { + sp1 = b->states.states + i; + if (sp1->id != i) + continue; + for (j = 0; j < i; j++) { + sp2 = b->states.states + j; + if (sp2->id != j) + continue; + b->equiv_used = 0; + _ure_add_equiv(i, j, b); + for (eq = 0, done = 0; eq < b->equiv_used; eq++) { + ls = b->states.states + b->equiv[eq].l; + rs = b->states.states + b->equiv[eq].r; + if (ls->accepting != rs->accepting || + ls->trans_used != rs->trans_used) { + done = 1; + break; + } + for (k = 0; k < ls->trans_used && + ls->trans[k].lhs == rs->trans[k].lhs; k++) ; + if (k < ls->trans_used) { + done = 1; + break; + } + + for (k = 0; k < ls->trans_used; k++) + _ure_add_equiv(ls->trans[k].rhs, rs->trans[k].rhs, b); + } + if (done == 0) + break; + } + for (eq = 0; j < i && eq < b->equiv_used; eq++) + b->states.states[b->equiv[eq].r].id = + b->states.states[b->equiv[eq].l].id; + } + + /* + * Renumber the states appropriately. + */ + for (i = eq = 0, sp1 = b->states.states; i < b->states.states_used; + sp1++, i++) + sp1->id = (sp1->id == i) ? eq++ : b->states.states[sp1->id].id; +} + +/************************************************************************* + * + * API. + * + *************************************************************************/ + +ure_buffer_t +ure_buffer_create(void) +{ + ure_buffer_t b; + + b = (ure_buffer_t) calloc(1, sizeof(_ure_buffer_t)); + + return b; +} + +void +ure_buffer_free(ure_buffer_t buf) +{ + unsigned long i; + + if (buf == 0) + return; + + if (buf->stack.slist_size > 0) + free((char *) buf->stack.slist); + + if (buf->expr_size > 0) + free((char *) buf->expr); + + for (i = 0; i < buf->symtab_size; i++) { + if (buf->symtab[i].states.slist_size > 0) + free((char *) buf->symtab[i].states.slist); + } + + if (buf->symtab_size > 0) + free((char *) buf->symtab); + + for (i = 0; i < buf->states.states_size; i++) { + if (buf->states.states[i].trans_size > 0) + free((char *) buf->states.states[i].trans); + if (buf->states.states[i].st.slist_size > 0) + free((char *) buf->states.states[i].st.slist); + } + + if (buf->states.states_size > 0) + free((char *) buf->states.states); + + if (buf->equiv_size > 0) + free((char *) buf->equiv); + + free((char *) buf); +} + +ure_dfa_t +ure_compile(ucs2_t *re, unsigned long relen, int casefold, ure_buffer_t buf) +{ + ucs2_t i, j, state; + _ure_state_t *sp; + _ure_dstate_t *dsp; + _ure_trans_t *tp; + ure_dfa_t dfa; + + if (re == 0 || *re == 0 || relen == 0 || buf == 0) + return 0; + + /* + * Reset the various fields of the compilation buffer. Default the flags + * to indicate the presense of the "^$" pattern. If any other pattern + * occurs, then this flag will be removed. This is done to catch this + * special pattern and handle it specially when matching. + */ + buf->flags = _URE_DFA_BLANKLINE | ((casefold) ? _URE_DFA_CASEFOLD : 0); + buf->reducing = 0; + buf->stack.slist_used = 0; + buf->expr_used = 0; + + for (i = 0; i < buf->symtab_used; i++) + buf->symtab[i].states.slist_used = 0; + buf->symtab_used = 0; + + for (i = 0; i < buf->states.states_used; i++) { + buf->states.states[i].st.slist_used = 0; + buf->states.states[i].trans_used = 0; + } + buf->states.states_used = 0; + + /* + * Construct the NFA. If this stage returns a 0, then an error occured or + * an empty expression was passed. + */ + if ((state = _ure_re2nfa(re, relen, buf)) == _URE_NOOP) + return 0; + + /* + * Do the expression reduction to get the initial DFA. + */ + _ure_reduce(state, buf); + + /* + * Merge all the equivalent DFA states. + */ + _ure_merge_equiv(buf); + + /* + * Construct the minimal DFA. + */ + dfa = (ure_dfa_t) malloc(sizeof(_ure_dfa_t)); + (void) memset((char *) dfa, '\0', sizeof(_ure_dfa_t)); + + dfa->flags = buf->flags & (_URE_DFA_CASEFOLD|_URE_DFA_BLANKLINE); + + /* + * Free up the NFA state groups and transfer the symbols from the buffer + * to the DFA. + */ + for (i = 0; i < buf->symtab_size; i++) { + if (buf->symtab[i].states.slist_size > 0) + free((char *) buf->symtab[i].states.slist); + } + dfa->syms = buf->symtab; + dfa->nsyms = buf->symtab_used; + + buf->symtab_used = buf->symtab_size = 0; + + /* + * Collect the total number of states and transitions needed for the DFA. + */ + for (i = state = 0, sp = buf->states.states; i < buf->states.states_used; + i++, sp++) { + if (sp->id == state) { + dfa->nstates++; + dfa->ntrans += sp->trans_used; + state++; + } + } + + /* + * Allocate enough space for the states and transitions. + */ + dfa->states = (_ure_dstate_t *) malloc(sizeof(_ure_dstate_t) * + dfa->nstates); + dfa->trans = (_ure_trans_t *) malloc(sizeof(_ure_trans_t) * dfa->ntrans); + + /* + * Actually transfer the DFA states from the buffer. + */ + dsp = dfa->states; + tp = dfa->trans; + for (i = state = 0, sp = buf->states.states; i < buf->states.states_used; + i++, sp++) { + if (sp->id == state) { + dsp->trans = tp; + dsp->ntrans = sp->trans_used; + dsp->accepting = sp->accepting; + + /* + * Add the transitions for the state. + */ + for (j = 0; j < dsp->ntrans; j++, tp++) { + tp->symbol = sp->trans[j].lhs; + tp->next_state = buf->states.states[sp->trans[j].rhs].id; + } + + dsp++; + state++; + } + } + + return dfa; +} + +void +ure_dfa_free(ure_dfa_t dfa) +{ + ucs2_t i; + + if (dfa == 0) + return; + + for (i = 0; i < dfa->nsyms; i++) { + if ((dfa->syms[i].type == _URE_CCLASS || + dfa->syms[i].type == _URE_NCCLASS) && + dfa->syms[i].sym.ccl.ranges_size > 0) + free((char *) dfa->syms[i].sym.ccl.ranges); + } + if (dfa->nsyms > 0) + free((char *) dfa->syms); + + if (dfa->nstates > 0) + free((char *) dfa->states); + if (dfa->ntrans > 0) + free((char *) dfa->trans); + free((char *) dfa); +} + +void +ure_write_dfa(ure_dfa_t dfa, FILE *out) +{ + ucs2_t i, j, k, h, l; + _ure_dstate_t *sp; + _ure_symtab_t *sym; + _ure_range_t *rp; + + if (dfa == 0 || out == 0) + return; + + /* + * Write all the different character classes. + */ + for (i = 0, sym = dfa->syms; i < dfa->nsyms; i++, sym++) { + if (sym->type == _URE_CCLASS || sym->type == _URE_NCCLASS) { + fprintf(out, "C%hd = ", sym->id); + if (sym->sym.ccl.ranges_used > 0) { + putc('[', out); + if (sym->type == _URE_NCCLASS) + putc('^', out); + } + if (sym->props != 0) { + if (sym->type == _URE_NCCLASS) + fprintf(out, "\\P"); + else + fprintf(out, "\\p"); + for (k = h = 0; k < 32; k++) { + if (sym->props & (1 << k)) { + if (h != 0) + putc(',', out); + fprintf(out, "%hd", k + 1); + h = 1; + } + } + } + /* + * Dump the ranges. + */ + for (k = 0, rp = sym->sym.ccl.ranges; + k < sym->sym.ccl.ranges_used; k++, rp++) { + /* + * Check for UTF16 characters. + */ + if (0x10000 <= rp->min_code && + rp->min_code <= 0x10ffff) { + h = (ucs2_t) (((rp->min_code - 0x10000) >> 10) + 0xd800); + l = (ucs2_t) (((rp->min_code - 0x10000) & 1023) + 0xdc00); + fprintf(out, "\\x%04hX\\x%04hX", h, l); + } else + fprintf(out, "\\x%04lX", rp->min_code & 0xffff); + if (rp->max_code != rp->min_code) { + putc('-', out); + if (rp->max_code >= 0x10000 && + rp->max_code <= 0x10ffff) { + h = (ucs2_t) (((rp->max_code - 0x10000) >> 10) + 0xd800); + l = (ucs2_t) (((rp->max_code - 0x10000) & 1023) + 0xdc00); + fprintf(out, "\\x%04hX\\x%04hX", h, l); + } else + fprintf(out, "\\x%04lX", rp->max_code & 0xffff); + } + } + if (sym->sym.ccl.ranges_used > 0) + putc(']', out); + putc('\n', out); + } + } + + for (i = 0, sp = dfa->states; i < dfa->nstates; i++, sp++) { + fprintf(out, "S%hd = ", i); + if (sp->accepting) { + fprintf(out, "1 "); + if (sp->ntrans) + fprintf(out, "| "); + } + for (j = 0; j < sp->ntrans; j++) { + if (j > 0) + fprintf(out, "| "); + + sym = dfa->syms + sp->trans[j].symbol; + switch (sym->type) { + case _URE_CHAR: + if (0x10000 <= sym->sym.chr && sym->sym.chr <= 0x10ffff) { + /* + * Take care of UTF16 characters. + */ + h = (ucs2_t) (((sym->sym.chr - 0x10000) >> 10) + 0xd800); + l = (ucs2_t) (((sym->sym.chr - 0x10000) & 1023) + 0xdc00); + fprintf(out, "\\x%04hX\\x%04hX ", h, l); + } else + fprintf(out, "\\x%04lX ", sym->sym.chr & 0xffff); + break; + case _URE_ANY_CHAR: + fprintf(out, "<any> "); + break; + case _URE_BOL_ANCHOR: + fprintf(out, "<bol-anchor> "); + break; + case _URE_EOL_ANCHOR: + fprintf(out, "<eol-anchor> "); + break; + case _URE_CCLASS: + case _URE_NCCLASS: + fprintf(out, "[C%hd] ", sym->id); + break; + } + fprintf(out, "S%hd", sp->trans[j].next_state); + if (j + 1 < sp->ntrans) + putc(' ', out); + } + putc('\n', out); + } +} + +#define _ure_issep(cc) ((cc) == '\n' || (cc) == '\r' || (cc) == 0x2028 ||\ + (cc) == 0x2029) + +int +ure_exec(ure_dfa_t dfa, int flags, ucs2_t *text, unsigned long textlen, + unsigned long *match_start, unsigned long *match_end) +{ + int i, j, matched, found, skip; + unsigned long ms, me; + ucs4_t c; + ucs2_t *sp, *ep, *lp; + _ure_dstate_t *stp; + _ure_symtab_t *sym; + _ure_range_t *rp; + + if (dfa == 0 || text == 0) + return 0; + + /* + * Handle the special case of an empty string matching the "^$" pattern. + */ + if (textlen == 0 && (dfa->flags & _URE_DFA_BLANKLINE)) { + *match_start = *match_end = 0; + return 1; + } + + sp = text; + ep = sp + textlen; + + ms = me = ~0; + + stp = dfa->states; + + for (found = skip = 0; found == 0 && sp < ep; ) { + lp = sp; + c = *sp++; + + /* + * Check to see if this is a high surrogate that should be + * combined with a following low surrogate. + */ + if (sp < ep && 0xd800 <= c && c <= 0xdbff && + 0xdc00 <= *sp && *sp <= 0xdfff) + c = 0x10000 + (((c & 0x03ff) << 10) | (*sp++ & 0x03ff)); + + /* + * Determine if the character is non-spacing and should be skipped. + */ + if (_ure_matches_properties(_URE_NONSPACING, c) && + (flags & URE_IGNORE_NONSPACING)) { + sp++; + continue; + } + + if (dfa->flags & _URE_DFA_CASEFOLD) + c = _ure_tolower(c); + + /* + * See if one of the transitions matches. + */ + for (i = 0, matched = 0; matched == 0 && i < stp->ntrans; i++) { + sym = dfa->syms + stp->trans[i].symbol; + switch (sym->type) { + case _URE_ANY_CHAR: + if ((flags & URE_DOT_MATCHES_SEPARATORS) || + !_ure_issep(c)) + matched = 1; + break; + case _URE_CHAR: + if (c == sym->sym.chr) + matched = 1; + break; + case _URE_BOL_ANCHOR: + if (lp == text) { + sp = lp; + matched = 1; + } else if (_ure_issep(c)) { + if (c == '\r' && sp < ep && *sp == '\n') + sp++; + lp = sp; + matched = 1; + } + break; + case _URE_EOL_ANCHOR: + if (_ure_issep(c)) { + /* + * Put the pointer back before the separator so the match + * end position will be correct. This case will also + * cause the `sp' pointer to be advanced over the current + * separator once the match end point has been recorded. + */ + sp = lp; + matched = 1; + } + break; + case _URE_CCLASS: + case _URE_NCCLASS: + if (sym->props != 0) + matched = _ure_matches_properties(sym->props, c); + for (j = 0, rp = sym->sym.ccl.ranges; + j < sym->sym.ccl.ranges_used; j++, rp++) { + if (rp->min_code <= c && c <= rp->max_code) + matched = 1; + } + if (sym->type == _URE_NCCLASS) + matched = !matched; + break; + } + + if (matched) { + if (ms == ~0UL) + ms = lp - text; + else + me = sp - text; + stp = dfa->states + stp->trans[i].next_state; + + /* + * If the match was an EOL anchor, adjust the pointer past the + * separator that caused the match. The correct match + * position has been recorded already. + */ + if (sym->type == _URE_EOL_ANCHOR) { + /* + * Skip the character that caused the match. + */ + sp++; + + /* + * Handle the infamous CRLF situation. + */ + if (sp < ep && c == '\r' && *sp == '\n') + sp++; + } + } + } + + if (matched == 0) { + if (stp->accepting == 0) { + /* + * If the last state was not accepting, then reset + * and start over. + */ + stp = dfa->states; + ms = me = ~0; + } else + /* + * The last state was accepting, so terminate the matching + * loop to avoid more work. + */ + found = 1; + } else if (sp == ep) { + if (!stp->accepting) { + /* + * This ugly hack is to make sure the end-of-line anchors + * match when the source text hits the end. This is only done + * if the last subexpression matches. + */ + for (i = 0; found == 0 && i < stp->ntrans; i++) { + sym = dfa->syms + stp->trans[i].symbol; + if (sym->type ==_URE_EOL_ANCHOR) { + stp = dfa->states + stp->trans[i].next_state; + if (stp->accepting) { + me = sp - text; + found = 1; + } else + break; + } + } + } else { + /* + * Make sure any conditions that match all the way to the end + * of the string match. + */ + found = 1; + me = sp - text; + } + } + } + + if (found == 0) + ms = me = ~0; + + *match_start = ms; + *match_end = me; + + return (ms != ~0UL) ? 1 : 0; +} |