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Diffstat (limited to 'regex.c')
| -rw-r--r-- | regex.c | 2807 |
1 files changed, 2807 insertions, 0 deletions
diff --git a/regex.c b/regex.c new file mode 100644 index 0000000000..686695cbe2 --- /dev/null +++ b/regex.c @@ -0,0 +1,2807 @@ +/* Extended regular expression matching and search library. + Copyright (C) 1985, 1989-90 Free Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 1, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ +/* Multi-byte extension added May, 1993 by t^2 (Takahiro Tanimoto) + Last change: May 21, 1993 by t^2 */ + + +/* To test, compile with -Dtest. This Dtestable feature turns this into + a self-contained program which reads a pattern, describes how it + compiles, then reads a string and searches for it. + + On the other hand, if you compile with both -Dtest and -Dcanned you + can run some tests we've already thought of. */ + +/* We write fatal error messages on standard error. */ +#include <stdio.h> + +/* isalpha(3) etc. are used for the character classes. */ +#include <ctype.h> +#include <sys/types.h> + +#include "config.h" +#include "defines.h" + +#ifdef __STDC__ +#define P(s) s +#define MALLOC_ARG_T size_t +#else +#define P(s) () +#define MALLOC_ARG_T unsigned +#define volatile +#define const +#endif + +/* #define NO_ALLOCA /* try it out for now */ +#ifndef NO_ALLOCA +/* Make alloca work the best possible way. */ +#ifdef __GNUC__ +#ifndef atarist +#ifndef alloca +#define alloca __builtin_alloca +#endif +#endif /* atarist */ +#else +#if defined(HAVE_ALLOCA_H) && !defined(__GNUC__) +#include <alloca.h> +#else +char *alloca(); +#endif +#endif /* __GNUC__ */ + +#ifdef _AIX +#pragma alloca +#endif + +#define RE_ALLOCATE alloca +#define FREE_VARIABLES() alloca(0) + +#define FREE_AND_RETURN_VOID(stackb) return +#define FREE_AND_RETURN(stackb,val) return(val) +#define DOUBLE_STACK(stackx,stackb,len) \ + (stackx = (unsigned char **) alloca(2 * len \ + * sizeof(unsigned char *)),\ + /* Only copy what is in use. */ \ + (unsigned char **) memcpy(stackx, stackb, len * sizeof (char *))) +#else /* NO_ALLOCA defined */ + +#define RE_ALLOCATE malloc + +#define FREE_VAR(var) if (var) free(var); var = NULL +#define FREE_VARIABLES() \ + do { \ + FREE_VAR(regstart); \ + FREE_VAR(regend); \ + FREE_VAR(best_regstart); \ + FREE_VAR(best_regend); \ + FREE_VAR(reg_info); \ + } while (0) + +#define FREE_AND_RETURN_VOID(stackb) free(stackb);return +#define FREE_AND_RETURN(stackb,val) free(stackb);return(val) +#define DOUBLE_STACK(stackx,stackb,len) \ + (unsigned char **)xrealloc(stackb, 2 * len * sizeof(unsigned char *)) +#endif /* NO_ALLOCA */ + +#define RE_TALLOC(n,t) ((t*)RE_ALLOCATE((n)*sizeof(t))) +#define TMALLOC(n,t) ((t*)xmalloc((n)*sizeof(t))) +#define TREALLOC(s,n,t) (s=((t*)xrealloc(s,(n)*sizeof(t)))) + +/* Get the interface, including the syntax bits. */ +#include "regex.h" + +static void store_jump P((char *, int, char *)); +static void insert_jump P((int, char *, char *, char *)); +static void store_jump_n P((char *, int, char *, unsigned)); +static void insert_jump_n P((int, char *, char *, char *, unsigned)); +static void insert_op_2 P((int, char *, char *, int, int )); +static int memcmp_translate P((unsigned char *, unsigned char *, + int, unsigned char *)); + +/* Define the syntax stuff, so we can do the \<, \>, etc. */ + +/* This must be nonzero for the wordchar and notwordchar pattern + commands in re_match_2. */ +#ifndef Sword +#define Sword 1 +#endif + +#define SYNTAX(c) re_syntax_table[c] + +static char re_syntax_table[256]; +static void init_syntax_once P((void)); + +#undef P + +#include "util.h" + +static void +init_syntax_once() +{ + register int c; + static int done = 0; + + if (done) + return; + + memset(re_syntax_table, 0, sizeof re_syntax_table); + + for (c = 'a'; c <= 'z'; c++) + re_syntax_table[c] = Sword; + + for (c = 'A'; c <= 'Z'; c++) + re_syntax_table[c] = Sword; + + for (c = '0'; c <= '9'; c++) + re_syntax_table[c] = Sword; + + re_syntax_table['_'] = Sword; + + /* Add specific syntax for ISO Latin-1. */ + for (c = 0300; c <= 0377; c++) + re_syntax_table[c] = Sword; + re_syntax_table[0327] = 0; + re_syntax_table[0367] = 0; + + done = 1; +} + +/* Sequents are missing isgraph. */ +#ifndef isgraph +#define isgraph(c) (isprint((c)) && !isspace((c))) +#endif + +/* These are the command codes that appear in compiled regular + expressions, one per byte. Some command codes are followed by + argument bytes. A command code can specify any interpretation + whatsoever for its arguments. Zero-bytes may appear in the compiled + regular expression. + + The value of `exactn' is needed in search.c (search_buffer) in emacs. + So regex.h defines a symbol `RE_EXACTN_VALUE' to be 1; the value of + `exactn' we use here must also be 1. */ + +enum regexpcode + { + unused=0, + exactn=1, /* Followed by one byte giving n, then by n literal bytes. */ + begline, /* Fail unless at beginning of line. */ + endline, /* Fail unless at end of line. */ + jump, /* Followed by two bytes giving relative address to jump to. */ + on_failure_jump, /* Followed by two bytes giving relative address of + place to resume at in case of failure. */ + finalize_jump, /* Throw away latest failure point and then jump to + address. */ + maybe_finalize_jump, /* Like jump but finalize if safe to do so. + This is used to jump back to the beginning + of a repeat. If the command that follows + this jump is clearly incompatible with the + one at the beginning of the repeat, such that + we can be sure that there is no use backtracking + out of repetitions already completed, + then we finalize. */ + dummy_failure_jump, /* Jump, and push a dummy failure point. This + failure point will be thrown away if an attempt + is made to use it for a failure. A + construct + makes this before the first repeat. Also + use it as an intermediary kind of jump when + compiling an or construct. */ + succeed_n, /* Used like on_failure_jump except has to succeed n times; + then gets turned into an on_failure_jump. The relative + address following it is useless until then. The + address is followed by two bytes containing n. */ + jump_n, /* Similar to jump, but jump n times only; also the relative + address following is in turn followed by yet two more bytes + containing n. */ + set_number_at, /* Set the following relative location to the + subsequent number. */ + anychar, /* Matches any (more or less) one character. */ + charset, /* Matches any one char belonging to specified set. + First following byte is number of bitmap bytes. + Then come bytes for a bitmap saying which chars are in. + Bits in each byte are ordered low-bit-first. + A character is in the set if its bit is 1. + A character too large to have a bit in the map + is automatically not in the set. */ + charset_not, /* Same parameters as charset, but match any character + that is not one of those specified. */ + start_memory, /* Start remembering the text that is matched, for + storing in a memory register. Followed by one + byte containing the register number. Register numbers + must be in the range 0 through RE_NREGS. */ + stop_memory, /* Stop remembering the text that is matched + and store it in a memory register. Followed by + one byte containing the register number. Register + numbers must be in the range 0 through RE_NREGS. */ + duplicate, /* Match a duplicate of something remembered. + Followed by one byte containing the index of the memory + register. */ + wordchar, /* Matches any word-constituent character. */ + notwordchar, /* Matches any char that is not a word-constituent. */ + wordbound, /* Succeeds if at a word boundary. */ + notwordbound,/* Succeeds if not at a word boundary. */ + }; + + +/* Number of failure points to allocate space for initially, + when matching. If this number is exceeded, more space is allocated, + so it is not a hard limit. */ + +#ifndef NFAILURES +#define NFAILURES 80 +#endif + +#if defined(CHAR_UNSIGNED) || defined(__CHAR_UNSIGNED__) +#define SIGN_EXTEND_CHAR(c) ((c)>(char)127?(c)-256:(c)) /* for IBM RT */ +#endif +#ifndef SIGN_EXTEND_CHAR +#define SIGN_EXTEND_CHAR(x) (x) +#endif + + +/* Store NUMBER in two contiguous bytes starting at DESTINATION. */ +#define STORE_NUMBER(destination, number) \ + { (destination)[0] = (number) & 0377; \ + (destination)[1] = (number) >> 8; } + +/* Same as STORE_NUMBER, except increment the destination pointer to + the byte after where the number is stored. Watch out that values for + DESTINATION such as p + 1 won't work, whereas p will. */ +#define STORE_NUMBER_AND_INCR(destination, number) \ + { STORE_NUMBER(destination, number); \ + (destination) += 2; } + + +/* Put into DESTINATION a number stored in two contingous bytes starting + at SOURCE. */ +#define EXTRACT_NUMBER(destination, source) \ + { (destination) = *(source) & 0377; \ + (destination) += SIGN_EXTEND_CHAR (*(char *)((source) + 1)) << 8; } + +/* Same as EXTRACT_NUMBER, except increment the pointer for source to + point to second byte of SOURCE. Note that SOURCE has to be a value + such as p, not, e.g., p + 1. */ +#define EXTRACT_NUMBER_AND_INCR(destination, source) \ + { EXTRACT_NUMBER(destination, source); \ + (source) += 2; } + + +/* Specify the precise syntax of regexps for compilation. This provides + for compatibility for various utilities which historically have + different, incompatible syntaxes. + + The argument SYNTAX is a bit-mask comprised of the various bits + defined in regex.h. */ + +long +re_set_syntax(syntax) + long syntax; +{ + long ret; + + ret = re_syntax_options; + re_syntax_options = syntax; + return ret; +} + +/* Set by re_set_syntax to the current regexp syntax to recognize. */ +long re_syntax_options = DEFAULT_MBCTYPE; + + +/* Macros for re_compile_pattern, which is found below these definitions. */ + +/* Fetch the next character in the uncompiled pattern---translating it + if necessary. Also cast from a signed character in the constant + string passed to us by the user to an unsigned char that we can use + as an array index (in, e.g., `translate'). */ +#define PATFETCH(c) \ + do {if (p == pend) goto end_of_pattern; \ + c = (unsigned char) *p++; \ + if (translate) c = (unsigned char)translate[c]; \ + } while (0) + +/* Fetch the next character in the uncompiled pattern, with no + translation. */ +#define PATFETCH_RAW(c) \ + do {if (p == pend) goto end_of_pattern; \ + c = (unsigned char) *p++; \ + } while (0) + +/* Go backwards one character in the pattern. */ +#define PATUNFETCH p-- + + +/* If the buffer isn't allocated when it comes in, use this. */ +#define INIT_BUF_SIZE 28 + +/* Make sure we have at least N more bytes of space in buffer. */ +#define GET_BUFFER_SPACE(n) \ + { \ + while (b - bufp->buffer + (n) >= bufp->allocated) \ + EXTEND_BUFFER; \ + } + +/* Make sure we have one more byte of buffer space and then add CH to it. */ +#define BUFPUSH(ch) \ + { \ + GET_BUFFER_SPACE(1); \ + *b++ = (char)(ch); \ + } + +/* Extend the buffer by twice its current size via reallociation and + reset the pointers that pointed into the old allocation to point to + the correct places in the new allocation. If extending the buffer + results in it being larger than 1 << 16, then flag memory exhausted. */ +#define EXTEND_BUFFER \ + { char *old_buffer = bufp->buffer; \ + if (bufp->allocated == (1L<<16)) goto too_big; \ + bufp->allocated *= 2; \ + if (bufp->allocated > (1L<<16)) bufp->allocated = (1L<<16); \ + bufp->buffer = (char *) xrealloc (bufp->buffer, bufp->allocated); \ + if (bufp->buffer == 0) \ + goto memory_exhausted; \ + b = (b - old_buffer) + bufp->buffer; \ + if (fixup_jump) \ + fixup_jump = (fixup_jump - old_buffer) + bufp->buffer; \ + if (laststart) \ + laststart = (laststart - old_buffer) + bufp->buffer; \ + begalt = (begalt - old_buffer) + bufp->buffer; \ + if (pending_exact) \ + pending_exact = (pending_exact - old_buffer) + bufp->buffer; \ + } + + +/* Set the bit for character C in a character set list. */ +#define SET_LIST_BIT(c) \ + (b[(unsigned char)(c) / BYTEWIDTH] \ + |= 1 << ((unsigned char)(c) % BYTEWIDTH)) + +/* Get the next unsigned number in the uncompiled pattern. */ +#define GET_UNSIGNED_NUMBER(num) \ + { if (p != pend) \ + { \ + PATFETCH(c); \ + while (isdigit(c)) \ + { \ + if (num < 0) \ + num = 0; \ + num = num * 10 + c - '0'; \ + if (p == pend) \ + break; \ + PATFETCH(c); \ + } \ + } \ + } + +/* Subroutines for re_compile_pattern. */ +/* static void store_jump(), insert_jump(), store_jump_n(), + insert_jump_n(), insert_op_2(); */ + +#define STORE_MBC(p, c) \ + ((p)[0] = (unsigned char)(c >> 8), (p)[1] = (unsigned char)(c)) +#define STORE_MBC_AND_INCR(p, c) \ + (*(p)++ = (unsigned char)(c >> 8), *(p)++ = (unsigned char)(c)) + +#define EXTRACT_MBC(p) \ + ((unsigned short)((unsigned char)(p)[0] << 8 | (unsigned char)(p)[1])) +#define EXTRACT_MBC_AND_INCR(p) \ + ((unsigned short)((p) += 2, (unsigned char)(p)[-2] << 8 | (unsigned char)(p)[-1])) + +#define EXTRACT_UNSIGNED(p) \ + ((unsigned char)(p)[0] | (unsigned char)(p)[1] << 8) +#define EXTRACT_UNSIGNED_AND_INCR(p) \ + ((p) += 2, (unsigned char)(p)[-2] | (unsigned char)(p)[-1] << 8) + +/* Handle (mb)?charset(_not)?. + + Structure of mbcharset(_not)? in compiled pattern. + + struct { + unsinged char id; mbcharset(_not)? + unsigned char sbc_size; + unsigned char sbc_map[sbc_size]; same as charset(_not)? up to here. + unsigned short mbc_size; number of intervals. + struct { + unsigned short beg; beginning of interval. + unsigned short end; end of interval. + } intervals[mbc_size]; + }; */ + +static void +set_list_bits(c1, c2, b) + unsigned short c1, c2; + unsigned char *b; +{ + unsigned char sbc_size = b[-1]; + unsigned short mbc_size = EXTRACT_UNSIGNED(&b[sbc_size]); + unsigned short beg, end, upb; + + if (c1 > c2) + return; + if ((int)c1 < 1 << BYTEWIDTH) { + upb = c2; + if (1 << BYTEWIDTH <= (int)upb) + upb = (1 << BYTEWIDTH) - 1; /* The last single-byte char */ + if (sbc_size <= (unsigned short)(upb / BYTEWIDTH)) { + /* Allocate maximum size so it never happens again. */ + /* NOTE: memcpy() would not work here. */ + memmove(&b[(1 << BYTEWIDTH) / BYTEWIDTH], &b[sbc_size], 2 + mbc_size*4); + memset(&b[sbc_size], 0, (1 << BYTEWIDTH) / BYTEWIDTH - sbc_size); + b[-1] = sbc_size = (1 << BYTEWIDTH) / BYTEWIDTH; + } + for (; c1 <= upb; c1++) + if (!ismbchar(c1)) + SET_LIST_BIT(c1); + if ((int)c2 < 1 << BYTEWIDTH) + return; + c1 = 0x8000; /* The first wide char */ + } + b = &b[sbc_size + 2]; + + for (beg = 0, upb = mbc_size; beg < upb; ) { + unsigned short mid = (unsigned short)(beg + upb) >> 1; + + if ((int)c1 - 1 > (int)EXTRACT_MBC(&b[mid*4 + 2])) + beg = mid + 1; + else + upb = mid; + } + + for (end = beg, upb = mbc_size; end < upb; ) { + unsigned short mid = (unsigned short)(end + upb) >> 1; + + if ((int)c2 >= (int)EXTRACT_MBC(&b[mid*4]) - 1) + end = mid + 1; + else + upb = mid; + } + + if (beg != end) { + if (c1 > EXTRACT_MBC(&b[beg*4])) + c1 = EXTRACT_MBC(&b[beg*4]); + if (c2 < EXTRACT_MBC(&b[(end - 1)*4])) + c2 = EXTRACT_MBC(&b[(end - 1)*4]); + } + if (end < mbc_size && end != beg + 1) + /* NOTE: memcpy() would not work here. */ + memmove(&b[(beg + 1)*4], &b[end*4], (mbc_size - end)*4); + STORE_MBC(&b[beg*4 + 0], c1); + STORE_MBC(&b[beg*4 + 2], c2); + mbc_size += beg - end + 1; + STORE_NUMBER(&b[-2], mbc_size); +} + +static int +is_in_list(c, b) + unsigned short c; + const unsigned char *b; +{ + unsigned short size; + unsigned short i, j; + int result = 0; + + size = *b++; + if ((int)c < 1<<BYTEWIDTH) { + if ((int)c / BYTEWIDTH < (int)size && b[c / BYTEWIDTH] & 1 << c % BYTEWIDTH) { + return 1; + } + } + b += size + 2; + size = EXTRACT_UNSIGNED(&b[-2]); + if (size == 0) return 0; + + if (b[(size-1)*4] == 0xff) { + i = c; + if ((int)c >= 1<<BYTEWIDTH) { + i = i>>BYTEWIDTH; + } + while (size>0 && b[size*4-2] == 0xff) { + size--; + if (b[size*4+1] <= i && i <= b[size*4+3]) { + result = 2; + break; + } + } + } + for (i = 0, j = size; i < j; ) { + unsigned short k = (unsigned short)(i + j) >> 1; + + if (c > EXTRACT_MBC(&b[k*4+2])) + i = k + 1; + else + j = k; + } + if (i < size && EXTRACT_MBC(&b[i*4]) <= c + && ((unsigned char)c != '\n' && (unsigned char)c != '\0')) + return 1; + return result; +} + +/* re_compile_pattern takes a regular-expression string + and converts it into a buffer full of byte commands for matching. + + PATTERN is the address of the pattern string + SIZE is the length of it. + BUFP is a struct re_pattern_buffer * which points to the info + on where to store the byte commands. + This structure contains a char * which points to the + actual space, which should have been obtained with malloc. + re_compile_pattern may use realloc to grow the buffer space. + + The number of bytes of commands can be found out by looking in + the `struct re_pattern_buffer' that bufp pointed to, after + re_compile_pattern returns. */ + +char * +re_compile_pattern(pattern, size, bufp) + char *pattern; + size_t size; + struct re_pattern_buffer *bufp; +{ + register char *b = bufp->buffer; + register char *p = pattern; + char *pend = pattern + size; + register unsigned c, c1; + char *p0; + int numlen; + + /* Address of the count-byte of the most recently inserted `exactn' + command. This makes it possible to tell whether a new exact-match + character can be added to that command or requires a new `exactn' + command. */ + + char *pending_exact = 0; + + /* Address of the place where a forward-jump should go to the end of + the containing expression. Each alternative of an `or', except the + last, ends with a forward-jump of this sort. */ + + char *fixup_jump = 0; + + /* Address of start of the most recently finished expression. + This tells postfix * where to find the start of its operand. */ + + char *laststart = 0; + + /* In processing a repeat, 1 means zero matches is allowed. */ + + char zero_times_ok; + + /* In processing a repeat, 1 means many matches is allowed. */ + + char many_times_ok; + + /* Address of beginning of regexp, or inside of last \(. */ + + char *begalt = b; + + /* In processing an interval, at least this many matches must be made. */ + int lower_bound; + + /* In processing an interval, at most this many matches can be made. */ + int upper_bound; + + /* Place in pattern (i.e., the {) to which to go back if the interval + is invalid. */ + char *beg_interval = 0; + + /* Stack of information saved by \( and restored by \). + Four stack elements are pushed by each \(: + First, the value of b. + Second, the value of fixup_jump. + Third, the value of regnum. + Fourth, the value of begalt. */ + + int stackb[40]; + int *stackp = stackb; + int *stacke = stackb + 40; + int *stackt; + + /* Counts \('s as they are encountered. Remembered for the matching \), + where it becomes the register number to put in the stop_memory + command. */ + + int regnum = 1; + int range = 0; + + /* How to translate the characters in the pattern. */ + char *translate = bufp->translate; + + bufp->fastmap_accurate = 0; + + /* Initialize the syntax table. */ + init_syntax_once(); + + if (bufp->allocated == 0) + { + bufp->allocated = INIT_BUF_SIZE; + if (bufp->buffer) + /* EXTEND_BUFFER loses when bufp->allocated is 0. */ + bufp->buffer = (char *) xrealloc (bufp->buffer, INIT_BUF_SIZE); + else + /* Caller did not allocate a buffer. Do it for them. */ + bufp->buffer = (char *) xmalloc(INIT_BUF_SIZE); + if (!bufp->buffer) goto memory_exhausted; + begalt = b = bufp->buffer; + } + + while (p != pend) + { + PATFETCH(c); + + switch (c) + { + case '$': + { + char *p1 = p; + /* When testing what follows the $, + look past the \-constructs that don't consume anything. */ + if (! (re_syntax_options & RE_CONTEXT_INDEP_OPS)) + while (p1 != pend) + { + if (*p1 == '\\' && p1 + 1 != pend + && (p1[1] == 'b' || p1[1] == 'B')) + p1 += 2; + else + break; + } + if (re_syntax_options & RE_TIGHT_VBAR) + { + if (! (re_syntax_options & RE_CONTEXT_INDEP_OPS) && p1 != pend) + goto normal_char; + /* Make operand of last vbar end before this `$'. */ + if (fixup_jump) + store_jump(fixup_jump, jump, b); + fixup_jump = 0; + BUFPUSH(endline); + break; + } + /* $ means succeed if at end of line, but only in special contexts. + If validly in the middle of a pattern, it is a normal character. */ + +#if 0 + /* not needed for perl4 compatible */ + if ((re_syntax_options & RE_CONTEXTUAL_INVALID_OPS) && p1 != pend) + goto invalid_pattern; +#endif + if (p1 == pend || *p1 == '\n' + || (re_syntax_options & RE_CONTEXT_INDEP_OPS) + || (re_syntax_options & RE_NO_BK_PARENS + ? *p1 == ')' + : *p1 == '\\' && p1[1] == ')') + || (re_syntax_options & RE_NO_BK_VBAR + ? *p1 == '|' + : *p1 == '\\' && p1[1] == '|')) + { + BUFPUSH(endline); + break; + } + goto normal_char; + } + case '^': + /* ^ means succeed if at beg of line, but only if no preceding + pattern. */ + + if ((re_syntax_options & RE_CONTEXTUAL_INVALID_OPS) && laststart) + goto invalid_pattern; + if (laststart && p - 2 >= pattern && p[-2] != '\n' + && !(re_syntax_options & RE_CONTEXT_INDEP_OPS)) + goto normal_char; + if (re_syntax_options & RE_TIGHT_VBAR) + { + if (p != pattern + 1 + && ! (re_syntax_options & RE_CONTEXT_INDEP_OPS)) + goto normal_char; + BUFPUSH(begline); + begalt = b; + } + else + { + BUFPUSH(begline); + } + break; + + case '+': + case '?': + if ((re_syntax_options & RE_BK_PLUS_QM) + || (re_syntax_options & RE_LIMITED_OPS)) + goto normal_char; + handle_plus: + case '*': + /* If there is no previous pattern, char not special. */ + if (!laststart) + { + if (re_syntax_options & RE_CONTEXTUAL_INVALID_OPS) + goto invalid_pattern; + else if (! (re_syntax_options & RE_CONTEXT_INDEP_OPS)) + goto normal_char; + } + /* If there is a sequence of repetition chars, + collapse it down to just one. */ + zero_times_ok = 0; + many_times_ok = 0; + while (1) + { + zero_times_ok |= c != '+'; + many_times_ok |= c != '?'; + if (p == pend) + break; + PATFETCH(c); + if (c == '*') + ; + else if (!(re_syntax_options & RE_BK_PLUS_QM) + && (c == '+' || c == '?')) + ; + else if ((re_syntax_options & RE_BK_PLUS_QM) + && c == '\\') + { + /* int c1; */ + PATFETCH(c1); + if (!(c1 == '+' || c1 == '?')) + { + PATUNFETCH; + PATUNFETCH; + break; + } + c = c1; + } + else + { + PATUNFETCH; + break; + } + } + + /* Star, etc. applied to an empty pattern is equivalent + to an empty pattern. */ + if (!laststart) + break; + + /* Now we know whether or not zero matches is allowed + and also whether or not two or more matches is allowed. */ + if (many_times_ok) + { + /* If more than one repetition is allowed, put in at the + end a backward relative jump from b to before the next + jump we're going to put in below (which jumps from + laststart to after this jump). */ + GET_BUFFER_SPACE(3); + store_jump(b, maybe_finalize_jump, laststart - 3); + b += 3; /* Because store_jump put stuff here. */ + } + /* On failure, jump from laststart to b + 3, which will be the + end of the buffer after this jump is inserted. */ + GET_BUFFER_SPACE(3); + insert_jump(on_failure_jump, laststart, b + 3, b); + pending_exact = 0; + b += 3; + if (!zero_times_ok) + { + /* At least one repetition is required, so insert a + dummy-failure before the initial on-failure-jump + instruction of the loop. This effects a skip over that + instruction the first time we hit that loop. */ + GET_BUFFER_SPACE(6); + insert_jump(dummy_failure_jump, laststart, laststart + 6, b); + b += 3; + } + break; + + case '.': + laststart = b; + BUFPUSH(anychar); + break; + + case '[': + if (p == pend) + goto invalid_pattern; + while (b - bufp->buffer + > bufp->allocated - 9 - (1 << BYTEWIDTH) / BYTEWIDTH) + EXTEND_BUFFER; + + laststart = b; + if (*p == '^') + { + BUFPUSH(charset_not); + p++; + } + else + BUFPUSH(charset); + p0 = p; + + BUFPUSH((1 << BYTEWIDTH) / BYTEWIDTH); + /* Clear the whole map */ + memset(b, 0, (1 << BYTEWIDTH) / BYTEWIDTH + 2); + + if ((re_syntax_options & RE_HAT_NOT_NEWLINE) && b[-2] == charset_not) + SET_LIST_BIT('\n'); + + + /* Read in characters and ranges, setting map bits. */ + while (1) + { + int size; + unsigned last = (unsigned)-1; + + if ((size = EXTRACT_UNSIGNED(&b[(1 << BYTEWIDTH) / BYTEWIDTH]))) { + /* Ensure the space is enough to hold another interval + of multi-byte chars in charset(_not)?. */ + size = (1 << BYTEWIDTH) / BYTEWIDTH + 2 + size*4 + 4; + while (b + size + 1 > bufp->buffer + bufp->allocated) + EXTEND_BUFFER; + } + range_retry: + PATFETCH(c); + + if (c == ']') { + if (p == p0 + 1) { + /* If this is an empty bracket expression. */ + if ((re_syntax_options & RE_NO_EMPTY_BRACKETS) + && p == pend) + goto invalid_pattern; + } + else + /* Stop if this isn't merely a ] inside a bracket + expression, but rather the end of a bracket + expression. */ + break; + } + if (ismbchar(c)) { + PATFETCH(c1); + c = c << BYTEWIDTH | c1; + } + + /* \ escapes characters when inside [...]. */ + if (c == '\\') { + PATFETCH(c); + switch (c) { + case 'w': + for (c = 0; c < (1 << BYTEWIDTH); c++) + if (SYNTAX(c) == Sword) + SET_LIST_BIT(c); + last = -1; + continue; + + case 'W': + for (c = 0; c < (1 << BYTEWIDTH); c++) + if (SYNTAX(c) != Sword) + SET_LIST_BIT(c); + if (re_syntax_options & RE_MBCTYPE_MASK) { + set_list_bits(0x8000, 0xffff, (unsigned char*)b); + } + last = -1; + continue; + + case 's': + for (c = 0; c < 256; c++) + if (isspace(c)) + SET_LIST_BIT(c); + last = -1; + continue; + + case 'S': + for (c = 0; c < 256; c++) + if (!isspace(c)) + SET_LIST_BIT(c); + if (re_syntax_options & RE_MBCTYPE_MASK) { + set_list_bits(0x8000, 0xffff, (unsigned char*)b); + } + last = -1; + continue; + + case 'd': + for (c = '0'; c <= '9'; c++) + SET_LIST_BIT(c); + last = -1; + continue; + + case 'D': + for (c = 0; c < 256; c++) + if (!isdigit(c)) + SET_LIST_BIT(c); + if (re_syntax_options & RE_MBCTYPE_MASK) { + set_list_bits(0x8000, 0xffff, (unsigned char*)b); + } + last = -1; + continue; + + case 'x': + c = scan_hex(p, 2, &numlen); + if ((re_syntax_options & RE_MBCTYPE_MASK) && c > 0x7f) + c = 0xff00 | c; + p += numlen; + break; + + case '0': case '1': case '2': case '3': case '4': + case '5': case '6': case '7': case '8': case '9': + PATUNFETCH; + c = scan_oct(p, 3, &numlen); + if ((re_syntax_options & RE_MBCTYPE_MASK) && ismbchar(c)) + c = 0xff00 | c; + p += numlen; + break; + + default: + if (ismbchar(c)) { + PATFETCH(c1); + c = c << 8 | c1; + } + break; + } + } + + /* Get a range. */ + if (range) { + if (last > c) + goto invalid_pattern; + + if ((re_syntax_options & RE_NO_HYPHEN_RANGE_END) + && c == '-' && *p != ']') + goto invalid_pattern; + + range = 0; + if (last < 1 << BYTEWIDTH && c < 1 << BYTEWIDTH) { + for (;last<=c;last++) + SET_LIST_BIT(last); + } + else { + set_list_bits(last, c, (unsigned char*)b); + } + } + else if (p[0] == '-' && p[1] != ']') { + last = c; + PATFETCH(c1); + range = 1; + goto range_retry; + } + else if (c < 1 << BYTEWIDTH) + SET_LIST_BIT(c); + else + set_list_bits(c, c, (unsigned char*)b); + } + + /* Discard any character set/class bitmap bytes that are all + 0 at the end of the map. Decrement the map-length byte too. */ + while ((int) b[-1] > 0 && b[b[-1] - 1] == 0) + b[-1]--; + if (b[-1] != (1 << BYTEWIDTH) / BYTEWIDTH) + memmove(&b[b[-1]], &b[(1 << BYTEWIDTH) / BYTEWIDTH], + 2 + EXTRACT_UNSIGNED (&b[(1 << BYTEWIDTH) / BYTEWIDTH])*4); + b += b[-1] + 2 + EXTRACT_UNSIGNED (&b[b[-1]])*4; + break; + + case '(': + if (! (re_syntax_options & RE_NO_BK_PARENS)) + goto normal_char; + else + goto handle_open; + + case ')': + if (! (re_syntax_options & RE_NO_BK_PARENS)) + goto normal_char; + else + goto handle_close; + + case '\n': + if (! (re_syntax_options & RE_NEWLINE_OR)) + goto normal_char; + else + goto handle_bar; + + case '|': +#if 0 + /* not needed for perl4 compatible */ + if ((re_syntax_options & RE_CONTEXTUAL_INVALID_OPS) + && (! laststart || p == pend)) + goto invalid_pattern; + else + if (! (re_syntax_options & RE_NO_BK_VBAR)) + goto normal_char; + else +#endif + goto handle_bar; + + case '{': + if (! ((re_syntax_options & RE_NO_BK_CURLY_BRACES) + && (re_syntax_options & RE_INTERVALS))) + goto normal_char; + else + goto handle_interval; + + case '\\': + if (p == pend) goto invalid_pattern; + /* Do not translate the character after the \, so that we can + distinguish, e.g., \B from \b, even if we normally would + translate, e.g., B to b. */ + PATFETCH_RAW(c); + switch (c) + { + case '(': + if (re_syntax_options & RE_NO_BK_PARENS) + goto normal_backsl; + handle_open: + if (stackp == stacke) goto nesting_too_deep; + + /* Laststart should point to the start_memory that we are about + to push (unless the pattern has RE_NREGS or more ('s). */ + /* obsolete: now RE_NREGS is just a default register size. */ + *stackp++ = b - bufp->buffer; + BUFPUSH(start_memory); + BUFPUSH(regnum); + *stackp++ = fixup_jump ? fixup_jump - bufp->buffer + 1 : 0; + *stackp++ = regnum++; + *stackp++ = begalt - bufp->buffer; + fixup_jump = 0; + laststart = 0; + begalt = b; + /* too many ()'s to fit in a byte. */ + if (regnum >= (1<<BYTEWIDTH)) goto too_big; + break; + + case ')': + if (re_syntax_options & RE_NO_BK_PARENS) + goto normal_backsl; + handle_close: + if (stackp == stackb) goto unmatched_close; + begalt = *--stackp + bufp->buffer; + if (fixup_jump) + store_jump(fixup_jump, jump, b); + BUFPUSH(stop_memory); + BUFPUSH(stackp[-1]); + stackp -= 2; + fixup_jump = *stackp ? *stackp + bufp->buffer - 1 : 0; + laststart = *--stackp + bufp->buffer; + break; + + case '|': + if ((re_syntax_options & RE_LIMITED_OPS) + || (re_syntax_options & RE_NO_BK_VBAR)) + goto normal_backsl; + handle_bar: + if (re_syntax_options & RE_LIMITED_OPS) + goto normal_char; + /* Insert before the previous alternative a jump which + jumps to this alternative if the former fails. */ + GET_BUFFER_SPACE(6); + insert_jump(on_failure_jump, begalt, b + 6, b); + pending_exact = 0; + b += 3; + /* The alternative before the previous alternative has a + jump after it which gets executed if it gets matched. + Adjust that jump so it will jump to the previous + alternative's analogous jump (put in below, which in + turn will jump to the next (if any) alternative's such + jump, etc.). The last such jump jumps to the correct + final destination. */ + if (fixup_jump) + store_jump(fixup_jump, jump, b); + + /* Leave space for a jump after previous alternative---to be + filled in later. */ + fixup_jump = b; + b += 3; + + laststart = 0; + begalt = b; + break; + + case '{': + if (! (re_syntax_options & RE_INTERVALS) + /* Let \{ be a literal. */ + || ((re_syntax_options & RE_INTERVALS) + && (re_syntax_options & RE_NO_BK_CURLY_BRACES)) + /* If it's the string "\{". */ + || (p - 2 == pattern && p == pend)) + goto normal_backsl; + handle_interval: + beg_interval = p - 1; /* The {. */ + /* If there is no previous pattern, this isn't an interval. */ + if (!laststart) + { + if (re_syntax_options & RE_CONTEXTUAL_INVALID_OPS) + goto invalid_pattern; + else + goto normal_backsl; + } + /* It also isn't an interval if not preceded by an re + matching a single character or subexpression, or if + the current type of intervals can't handle back + references and the previous thing is a back reference. */ + if (! (*laststart == anychar + || *laststart == charset + || *laststart == charset_not + || *laststart == wordchar + || *laststart == notwordchar + || *laststart == start_memory + || (*laststart == exactn + && (laststart[1] == 1 + || laststart[1] == 2 && ismbchar(laststart[2]))) + || (! (re_syntax_options & RE_NO_BK_REFS) + && *laststart == duplicate))) + { + if (re_syntax_options & RE_NO_BK_CURLY_BRACES) + goto normal_char; + + /* Posix extended syntax is handled in previous + statement; this is for Posix basic syntax. */ + if (re_syntax_options & RE_INTERVALS) + goto invalid_pattern; + + goto normal_backsl; + } + lower_bound = -1; /* So can see if are set. */ + upper_bound = -1; + GET_UNSIGNED_NUMBER(lower_bound); + if (c == ',') + { + GET_UNSIGNED_NUMBER(upper_bound); + if (upper_bound < 0) + upper_bound = RE_DUP_MAX; + } + if (upper_bound < 0) + upper_bound = lower_bound; + if (! (re_syntax_options & RE_NO_BK_CURLY_BRACES)) + { + if (c != '\\') + goto invalid_pattern; + PATFETCH(c); + } + if (c != '}' || lower_bound < 0 || upper_bound > RE_DUP_MAX + || lower_bound > upper_bound + || ((re_syntax_options & RE_NO_BK_CURLY_BRACES) + && p != pend && *p == '{')) + { + if (re_syntax_options & RE_NO_BK_CURLY_BRACES) + goto unfetch_interval; + else + goto invalid_pattern; + } + + /* If upper_bound is zero, don't want to succeed at all; + jump from laststart to b + 3, which will be the end of + the buffer after this jump is inserted. */ + + if (upper_bound == 0) + { + GET_BUFFER_SPACE(3); + insert_jump(jump, laststart, b + 3, b); + b += 3; + } + + /* Otherwise, after lower_bound number of succeeds, jump + to after the jump_n which will be inserted at the end + of the buffer, and insert that jump_n. */ + else + { /* Set to 5 if only one repetition is allowed and + hence no jump_n is inserted at the current end of + the buffer; then only space for the succeed_n is + needed. Otherwise, need space for both the + succeed_n and the jump_n. */ + + unsigned slots_needed = upper_bound == 1 ? 5 : 10; + + GET_BUFFER_SPACE(slots_needed); + /* Initialize the succeed_n to n, even though it will + be set by its attendant set_number_at, because + re_compile_fastmap will need to know it. Jump to + what the end of buffer will be after inserting + this succeed_n and possibly appending a jump_n. */ + insert_jump_n(succeed_n, laststart, b + slots_needed, + b, lower_bound); + b += 5; /* Just increment for the succeed_n here. */ + + /* When hit this when matching, set the succeed_n's n. */ + GET_BUFFER_SPACE(5); + insert_op_2(set_number_at, laststart, b, 5, lower_bound); + b += 5; + + /* More than one repetition is allowed, so put in at + the end of the buffer a backward jump from b to the + succeed_n we put in above. By the time we've gotten + to this jump when matching, we'll have matched once + already, so jump back only upper_bound - 1 times. */ + + if (upper_bound > 1) + { + GET_BUFFER_SPACE(15); + store_jump_n(b, jump_n, laststart+5, upper_bound - 1); + b += 5; + /* When hit this when matching, reset the + preceding jump_n's n to upper_bound - 1. */ + insert_op_2(set_number_at, laststart, b, b - laststart, upper_bound - 1); + b += 5; + + BUFPUSH(set_number_at); + STORE_NUMBER_AND_INCR(b, -5); + STORE_NUMBER_AND_INCR(b, upper_bound - 1); + } + } + pending_exact = 0; + beg_interval = 0; + break; + + + unfetch_interval: + /* If an invalid interval, match the characters as literals. */ + if (beg_interval) + p = beg_interval; + else + { + fprintf(stderr, + "regex: no interval beginning to which to backtrack.\n"); + exit (1); + } + + beg_interval = 0; + PATFETCH(c); /* normal_char expects char in `c'. */ + goto normal_char; + break; + + case 's': + case 'S': + case 'd': + case 'D': + while (b - bufp->buffer + > bufp->allocated - 9 - (1 << BYTEWIDTH) / BYTEWIDTH) + EXTEND_BUFFER; + + laststart = b; + if (c == 's' || c == 'd') { + BUFPUSH(charset); + } + else { + BUFPUSH(charset_not); + } + + BUFPUSH((1 << BYTEWIDTH) / BYTEWIDTH); + memset(b, 0, (1 << BYTEWIDTH) / BYTEWIDTH + 2); + if (c == 's' || c == 'S') { + SET_LIST_BIT(' '); + SET_LIST_BIT('\t'); + SET_LIST_BIT('\n'); + SET_LIST_BIT('\r'); + SET_LIST_BIT('\f'); + } + else { + char cc; + + for (cc = '0'; cc <= '9'; cc++) { + SET_LIST_BIT(cc); + } + } + + while ((int) b[-1] > 0 && b[b[-1] - 1] == 0) + b[-1]--; + if (b[-1] != (1 << BYTEWIDTH) / BYTEWIDTH) + memmove(&b[b[-1]], &b[(1 << BYTEWIDTH) / BYTEWIDTH], + 2 + EXTRACT_UNSIGNED(&b[(1 << BYTEWIDTH) / BYTEWIDTH])*4); + b += b[-1] + 2 + EXTRACT_UNSIGNED(&b[b[-1]])*4; + break; + + case 'w': + laststart = b; + BUFPUSH(wordchar); + break; + + case 'W': + laststart = b; + BUFPUSH(notwordchar); + break; + + case 'b': + BUFPUSH(wordbound); + break; + + case 'B': + BUFPUSH(notwordbound); + break; + + /* hex */ + case 'x': + c1 = 0; + c = scan_hex(p, 2, &numlen); + p += numlen; + if ((re_syntax_options & RE_MBCTYPE_MASK) && c > 0x7f) + c1 = 0xff; + goto numeric_char; + + /* octal */ + case '0': + c1 = 0; + c = scan_oct(p, 3, &numlen); + p += numlen; + if ((re_syntax_options & RE_MBCTYPE_MASK) && c > 0x7f) + c1 = 0xff; + goto numeric_char; + + /* back-ref or octal */ + case '1': case '2': case '3': + case '4': case '5': case '6': + case '7': case '8': case '9': + { + char *p_save; + + PATUNFETCH; + p_save = p; + + c1 = 0; + GET_UNSIGNED_NUMBER(c1); + if (p < pend) PATUNFETCH; + + if (c1 >= regnum) { + /* need to get octal */ + p = p_save; + c = scan_oct(p_save, 3, &numlen); + p = p_save + numlen; + c1 = 0; + if ((re_syntax_options & RE_MBCTYPE_MASK) && c > 0x7f) + c1 = 0xff; + goto numeric_char; + } + } + + /* Can't back reference to a subexpression if inside of it. */ + for (stackt = stackp - 2; stackt > stackb; stackt -= 4) + if (*stackt == c1) + goto normal_char; + laststart = b; + BUFPUSH(duplicate); + BUFPUSH(c1); + break; + + case '+': + case '?': + if (re_syntax_options & RE_BK_PLUS_QM) + goto handle_plus; + else + goto normal_backsl; + break; + + default: + normal_backsl: + goto normal_char; + } + break; + + default: + normal_char: /* Expects the character in `c'. */ + c1 = 0; + if (ismbchar(c)) { + c1 = c; + PATFETCH(c); + } + else if (c > 0x7f) { + c1 = 0xff; + } + numeric_char: + if (!pending_exact || pending_exact + *pending_exact + 1 != b + || *pending_exact >= (c1 ? 0176 : 0177) + || *p == '*' || *p == '^' + || ((re_syntax_options & RE_BK_PLUS_QM) + ? *p == '\\' && (p[1] == '+' || p[1] == '?') + : (*p == '+' || *p == '?')) + || ((re_syntax_options & RE_INTERVALS) + && ((re_syntax_options & RE_NO_BK_CURLY_BRACES) + ? *p == '{' + : (p[0] == '\\' && p[1] == '{')))) + { + laststart = b; + BUFPUSH(exactn); + pending_exact = b; + BUFPUSH(0); + } + if (c1) { + BUFPUSH(c1); + (*pending_exact)++; + } + BUFPUSH(c); + (*pending_exact)++; + } + } + + if (fixup_jump) + store_jump(fixup_jump, jump, b); + + if (stackp != stackb) goto unmatched_open; + + bufp->used = b - bufp->buffer; + bufp->re_nsub = regnum; + return 0; + + invalid_char: + return "Invalid character in regular expression"; + + invalid_pattern: + return "Invalid regular expression"; + + unmatched_open: + return "Unmatched ("; + + unmatched_close: + return "Unmatched )"; + + end_of_pattern: + return "Premature end of regular expression"; + + nesting_too_deep: + return "Nesting too deep"; + + too_big: + return "Regular expression too big"; + + memory_exhausted: + return "Memory exhausted"; +} + + +/* Store a jump of the form <OPCODE> <relative address>. + Store in the location FROM a jump operation to jump to relative + address FROM - TO. OPCODE is the opcode to store. */ + +static void +store_jump(from, opcode, to) + char *from, *to; + int opcode; +{ + from[0] = (char)opcode; + STORE_NUMBER(from + 1, to - (from + 3)); +} + + +/* Open up space before char FROM, and insert there a jump to TO. + CURRENT_END gives the end of the storage not in use, so we know + how much data to copy up. OP is the opcode of the jump to insert. + + If you call this function, you must zero out pending_exact. */ + +static void +insert_jump(op, from, to, current_end) + int op; + char *from, *to, *current_end; +{ + register char *pfrom = current_end; /* Copy from here... */ + register char *pto = current_end + 3; /* ...to here. */ + + while (pfrom != from) + *--pto = *--pfrom; + store_jump(from, op, to); +} + + +/* Store a jump of the form <opcode> <relative address> <n> . + + Store in the location FROM a jump operation to jump to relative + address FROM - TO. OPCODE is the opcode to store, N is a number the + jump uses, say, to decide how many times to jump. + + If you call this function, you must zero out pending_exact. */ + +static void +store_jump_n(from, opcode, to, n) + char *from, *to; + int opcode; + unsigned n; +{ + from[0] = (char)opcode; + STORE_NUMBER(from + 1, to - (from + 3)); + STORE_NUMBER(from + 3, n); +} + + +/* Similar to insert_jump, but handles a jump which needs an extra + number to handle minimum and maximum cases. Open up space at + location FROM, and insert there a jump to TO. CURRENT_END gives the + end of the storage in use, so we know how much data to copy up. OP is + the opcode of the jump to insert. + + If you call this function, you must zero out pending_exact. */ + +static void +insert_jump_n(op, from, to, current_end, n) + int op; + char *from, *to, *current_end; + unsigned n; +{ + register char *pfrom = current_end; /* Copy from here... */ + register char *pto = current_end + 5; /* ...to here. */ + + while (pfrom != from) + *--pto = *--pfrom; + store_jump_n(from, op, to, n); +} + + +/* Open up space at location THERE, and insert operation OP followed by + NUM_1 and NUM_2. CURRENT_END gives the end of the storage in use, so + we know how much data to copy up. + + If you call this function, you must zero out pending_exact. */ + +static void +insert_op_2(op, there, current_end, num_1, num_2) + int op; + char *there, *current_end; + int num_1, num_2; +{ + register char *pfrom = current_end; /* Copy from here... */ + register char *pto = current_end + 5; /* ...to here. */ + + while (pfrom != there) + *--pto = *--pfrom; + + there[0] = (char)op; + STORE_NUMBER(there + 1, num_1); + STORE_NUMBER(there + 3, num_2); +} + + + +/* Given a pattern, compute a fastmap from it. The fastmap records + which of the (1 << BYTEWIDTH) possible characters can start a string + that matches the pattern. This fastmap is used by re_search to skip + quickly over totally implausible text. + + The caller must supply the address of a (1 << BYTEWIDTH)-byte data + area as bufp->fastmap. + The other components of bufp describe the pattern to be used. */ + +void +re_compile_fastmap(bufp) + struct re_pattern_buffer *bufp; +{ + unsigned char *pattern = (unsigned char *) bufp->buffer; + int size = bufp->used; + register char *fastmap = bufp->fastmap; + register unsigned char *p = pattern; + register unsigned char *pend = pattern + size; + register int j, k; + unsigned char *translate = (unsigned char *)bufp->translate; + unsigned is_a_succeed_n; + + unsigned char **stackb; + unsigned char **stackp; + stackb = RE_TALLOC(NFAILURES, unsigned char*); + stackp = stackb; + + memset(fastmap, 0, (1 << BYTEWIDTH)); + bufp->fastmap_accurate = 1; + bufp->can_be_null = 0; + + while (p) + { + is_a_succeed_n = 0; + if (p == pend) + { + bufp->can_be_null = 1; + break; + } +#ifdef SWITCH_ENUM_BUG + switch ((int) ((enum regexpcode)*p++)) +#else + switch ((enum regexpcode)*p++) +#endif + { + case exactn: + if (p[1] == 0xff) { + if (translate) + fastmap[translate[p[2]]] = 2; + else + fastmap[p[2]] = 2; + } + else if (translate) + fastmap[translate[p[1]]] = 1; + else + fastmap[p[1]] = 1; + break; + + case begline: + case wordbound: + case notwordbound: + continue; + + case endline: + if (translate) + fastmap[translate['\n']] = 1; + else + fastmap['\n'] = 1; + + if (bufp->can_be_null == 0) + bufp->can_be_null = 2; + break; + + case jump_n: + case finalize_jump: + case maybe_finalize_jump: + case jump: + case dummy_failure_jump: + EXTRACT_NUMBER_AND_INCR(j, p); + p += j; + if (j > 0) + continue; + /* Jump backward reached implies we just went through + the body of a loop and matched nothing. + Opcode jumped to should be an on_failure_jump. + Just treat it like an ordinary jump. + For a * loop, it has pushed its failure point already; + If so, discard that as redundant. */ + + if ((enum regexpcode) *p != on_failure_jump + && (enum regexpcode) *p != succeed_n) + continue; + p++; + EXTRACT_NUMBER_AND_INCR(j, p); + p += j; + if (stackp != stackb && *stackp == p) + stackp--; + continue; + + case on_failure_jump: + handle_on_failure_jump: + EXTRACT_NUMBER_AND_INCR(j, p); + *++stackp = p + j; + if (is_a_succeed_n) + EXTRACT_NUMBER_AND_INCR(k, p); /* Skip the n. */ + continue; + + case succeed_n: + is_a_succeed_n = 1; + /* Get to the number of times to succeed. */ + p += 2; + /* Increment p past the n for when k != 0. */ + EXTRACT_NUMBER_AND_INCR(k, p); + if (k == 0) + { + p -= 4; + goto handle_on_failure_jump; + } + continue; + + case set_number_at: + p += 4; + continue; + + case start_memory: + case stop_memory: + p++; + continue; + + case duplicate: + bufp->can_be_null = 1; + fastmap['\n'] = 1; + case anychar: + for (j = 0; j < (1 << BYTEWIDTH); j++) + if (j != '\n') + fastmap[j] = 1; + if (bufp->can_be_null) + { + FREE_AND_RETURN_VOID(stackb); + } + /* Don't return; check the alternative paths + so we can set can_be_null if appropriate. */ + break; + + case wordchar: + for (j = 0; j < (1 << BYTEWIDTH); j++) + if (SYNTAX(j) == Sword) + fastmap[j] = 1; + break; + + case notwordchar: + for (j = 0; j < 0x80; j++) + if (SYNTAX(j) != Sword) + fastmap[j] = 1; + for (j = 0x80; j < (1 << BYTEWIDTH); j++) + fastmap[j] = 1; + break; + + case charset: + /* NOTE: Charset for single-byte chars never contain + multi-byte char. See set_list_bits(). */ + for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--) + if (p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH))) + { + if (translate) + fastmap[translate[j]] = 1; + else + fastmap[j] = 1; + } + { + unsigned short size; + unsigned c, end; + + p += p[-1] + 2; + size = EXTRACT_UNSIGNED(&p[-2]); + for (j = 0; j < (int)size; j++) { + if ((unsigned char)p[j*4] == 0xff) { + for (c = (unsigned char)p[j*4+1], + end = (unsigned char)p[j*4+3]; + c <= end; c++) { + fastmap[c] = 2; + } + } + else { + /* set bits for 1st bytes of multi-byte chars. */ + for (c = (unsigned char)p[j*4], + end = (unsigned char)p[j*4 + 2]; + c <= end; c++) { + /* NOTE: Charset for multi-byte chars might contain + single-byte chars. We must reject them. */ + if (ismbchar(c)) + fastmap[c] = 1; + } + } + } + } + break; + + case charset_not: + /* S: set of all single-byte chars. + M: set of all first bytes that can start multi-byte chars. + s: any set of single-byte chars. + m: any set of first bytes that can start multi-byte chars. + + We assume S+M = U. + ___ _ _ + s+m = (S*s+M*m). */ + /* Chars beyond end of map must be allowed */ + /* NOTE: Charset_not for single-byte chars might contain + multi-byte chars. See set_list_bits(). */ + for (j = *p * BYTEWIDTH; j < (1 << BYTEWIDTH); j++) + if (!ismbchar(j)) + fastmap[j] = 1; + + for (j = *p++ * BYTEWIDTH - 1; j >= 0; j--) + if (!(p[j / BYTEWIDTH] & (1 << (j % BYTEWIDTH)))) + { + if (!ismbchar(j)) + fastmap[j] = 1; + } + { + unsigned short size; + unsigned char c, beg; + + p += p[-1] + 2; + size = EXTRACT_UNSIGNED(&p[-2]); + if (size == 0) { + for (j = 0x80; j < (1 << BYTEWIDTH); j++) + if (ismbchar(j)) + fastmap[j] = 1; + } + for (j = 0,c = 0x80;j < (int)size; j++) { + if ((unsigned char)p[j*4] == 0xff) { + for (beg = (unsigned char)p[j*4+1]; c < beg; c++) + fastmap[c] = 2; + c = (unsigned char)p[j*4+3] + 1; + } + else { + for (beg = (unsigned char)p[j*4 + 0]; c < beg; c++) + if (ismbchar(c)) + fastmap[c] = 1; + c = (unsigned char)p[j*4 + 2] + 1; + } + } + } + break; + + case unused: /* pacify gcc -Wall */ + break; + } + + /* Get here means we have successfully found the possible starting + characters of one path of the pattern. We need not follow this + path any farther. Instead, look at the next alternative + remembered in the stack. */ + if (stackp != stackb) + p = *stackp--; + else + break; + } + FREE_AND_RETURN_VOID(stackb); +} + + + + +/* Using the compiled pattern in BUFP->buffer, first tries to match + STRING, starting first at index STARTPOS, then at STARTPOS + 1, and + so on. RANGE is the number of places to try before giving up. If + RANGE is negative, it searches backwards, i.e., the starting + positions tried are STARTPOS, STARTPOS - 1, etc. STRING is of SIZE. + In REGS, return the indices of STRING that matched the entire + BUFP->buffer and its contained subexpressions. + + The value returned is the position in the strings at which the match + was found, or -1 if no match was found, or -2 if error (such as + failure stack overflow). */ + +int +re_search(bufp, string, size, startpos, range, regs) + struct re_pattern_buffer *bufp; + char *string; + int size, startpos, range; + struct re_registers *regs; +{ + register char *fastmap = bufp->fastmap; + register unsigned char *translate = (unsigned char *) bufp->translate; + int val, anchor = 0; + + /* Check for out-of-range starting position. */ + if (startpos < 0 || startpos > size) + return -1; + + /* Update the fastmap now if not correct already. */ + if (fastmap && !bufp->fastmap_accurate) { + re_compile_fastmap (bufp); + } + + if (bufp->used > 0 && (enum regexpcode)bufp->buffer[0] == begline) + anchor = 1; + + for (;;) + { + /* If a fastmap is supplied, skip quickly over characters that + cannot possibly be the start of a match. Note, however, that + if the pattern can possibly match the null string, we must + test it at each starting point so that we take the first null + string we get. */ + + if (fastmap && startpos < size + && bufp->can_be_null != 1 && !(anchor && startpos == 0)) + { + if (range > 0) /* Searching forwards. */ + { + register int lim = 0; + register unsigned char *p, c; + int irange = range; + + lim = range - (size - startpos); + p = (unsigned char *)&(string[startpos]); + + while (range > lim) { + c = *p++; + if (ismbchar(c)) { + if (fastmap[c]) + break; + c = *p++; + range--; + if (fastmap[c] == 2) + break; + } + else + if (fastmap[translate ? translate[c] : c]) + break; + range--; + } + startpos += irange - range; + } + else /* Searching backwards. */ + { + register unsigned char c; + + c = string[startpos]; + c &= 0xff; + if (translate ? !fastmap[translate[c]] : !fastmap[c]) + goto advance; + } + } + + if (anchor && startpos > 0 && startpos < size + && string[startpos-1] != '\n') goto advance; + + if (fastmap && startpos == size && range >= 0 + && (bufp->can_be_null == 0 || + (bufp->can_be_null == 2 && size > 0 + && string[startpos-1] == '\n'))) + return -1; + + val = re_match(bufp, string, size, startpos, regs); + if (val >= 0) + return startpos; + if (val == -2) + return -2; + +#ifndef NO_ALLOCA +#ifdef cALLOCA + alloca(0); +#endif /* cALLOCA */ + +#endif /* NO_ALLOCA */ + advance: + if (!range) + break; + else if (range > 0) { + const char *d = string + startpos; + + if (ismbchar(*d)) { + range--, startpos++; + if (!range) + break; + } + range--, startpos++; + } + else { + range++, startpos--; + { + const char *s, *d, *p; + + s = string; d = string + startpos; + for (p = d; p-- > s && ismbchar(*p); ) + /* --p >= s would not work on 80[12]?86. + (when the offset of s equals 0 other than huge model.) */ + ; + if (!((d - p) & 1)) { + if (!range) + break; + range++, startpos--; + } + } + } + } + return -1; +} + + + + +/* The following are used for re_match, defined below: */ + +/* Roughly the maximum number of failure points on the stack. Would be + exactly that if always pushed MAX_NUM_FAILURE_ITEMS each time we failed. */ + +int re_max_failures = 2000; + +/* Routine used by re_match. */ +/* static int memcmp_translate(); *//* already declared */ + + +/* Structure and accessing macros used in re_match: */ + +struct register_info +{ + unsigned is_active : 1; + unsigned matched_something : 1; +}; + +#define IS_ACTIVE(R) ((R).is_active) +#define MATCHED_SOMETHING(R) ((R).matched_something) + + +/* Macros used by re_match: */ + +/* I.e., regstart, regend, and reg_info. */ + +#define NUM_REG_ITEMS 3 + +/* We push at most this many things on the stack whenever we + fail. The `+ 2' refers to PATTERN_PLACE and STRING_PLACE, which are + arguments to the PUSH_FAILURE_POINT macro. */ + +#define MAX_NUM_FAILURE_ITEMS (num_regs * NUM_REG_ITEMS + 2) + + +/* We push this many things on the stack whenever we fail. */ + +#define NUM_FAILURE_ITEMS (last_used_reg * NUM_REG_ITEMS + 2) + + +/* This pushes most of the information about the current state we will want + if we ever fail back to it. */ + +#define PUSH_FAILURE_POINT(pattern_place, string_place) \ + { \ + long last_used_reg, this_reg; \ + \ + /* Find out how many registers are active or have been matched. \ + (Aside from register zero, which is only set at the end.) */ \ + for (last_used_reg = num_regs - 1; last_used_reg > 0; last_used_reg--)\ + if (regstart[last_used_reg] != (unsigned char *)(-1L)) \ + break; \ + \ + if (stacke - stackp <= NUM_FAILURE_ITEMS) \ + { \ + unsigned char **stackx; \ + unsigned int len = stacke - stackb; \ + if (len > re_max_failures * MAX_NUM_FAILURE_ITEMS) \ + { \ + FREE_VARIABLES(); \ + FREE_AND_RETURN(stackb,(-2)); \ + } \ + \ + /* Roughly double the size of the stack. */ \ + stackx = DOUBLE_STACK(stackx,stackb,len); \ + /* Rearrange the pointers. */ \ + stackp = stackx + (stackp - stackb); \ + stackb = stackx; \ + stacke = stackb + 2 * len; \ + } \ + \ + /* Now push the info for each of those registers. */ \ + for (this_reg = 1; this_reg <= last_used_reg; this_reg++) \ + { \ + *stackp++ = regstart[this_reg]; \ + *stackp++ = regend[this_reg]; \ + *stackp++ = (unsigned char *)®_info[this_reg]; \ + } \ + \ + /* Push how many registers we saved. */ \ + *stackp++ = (unsigned char *)last_used_reg; \ + \ + *stackp++ = pattern_place; \ + *stackp++ = string_place; \ + } + + +/* This pops what PUSH_FAILURE_POINT pushes. */ + +#define POP_FAILURE_POINT() \ + { \ + int temp; \ + stackp -= 2; /* Remove failure points. */ \ + temp = (int) *--stackp; /* How many regs pushed. */ \ + temp *= NUM_REG_ITEMS; /* How much to take off the stack. */ \ + stackp -= temp; /* Remove the register info. */ \ + } + +#define PREFETCH if (d == dend) goto fail + +/* Call this when have matched something; it sets `matched' flags for the + registers corresponding to the subexpressions of which we currently + are inside. */ +#define SET_REGS_MATCHED \ + { unsigned this_reg; \ + for (this_reg = 0; this_reg < num_regs; this_reg++) \ + { \ + if (IS_ACTIVE(reg_info[this_reg])) \ + MATCHED_SOMETHING(reg_info[this_reg]) = 1; \ + else \ + MATCHED_SOMETHING(reg_info[this_reg]) = 0; \ + } \ + } + +#define AT_STRINGS_BEG (d == string) +#define AT_STRINGS_END (d == dend) + +#define AT_WORD_BOUNDARY \ + (AT_STRINGS_BEG || AT_STRINGS_END || IS_A_LETTER (d - 1) != IS_A_LETTER (d)) + +/* We have two special cases to check for: + 1) if we're past the end of string1, we have to look at the first + character in string2; + 2) if we're before the beginning of string2, we have to look at the + last character in string1; we assume there is a string1, so use + this in conjunction with AT_STRINGS_BEG. */ +#define IS_A_LETTER(d) (SYNTAX(*(d)) == Sword) + +static void +init_regs(regs, num_regs) + struct re_registers *regs; + unsigned num_regs; +{ + int i; + + regs->num_regs = num_regs; + if (num_regs < RE_NREGS) + num_regs = RE_NREGS; + + if (regs->allocated == 0) { + regs->beg = TMALLOC(num_regs, int); + regs->end = TMALLOC(num_regs, int); + regs->allocated = num_regs; + } + else if (regs->allocated < num_regs) { + TREALLOC(regs->beg, num_regs, int); + TREALLOC(regs->end, num_regs, int); + } + for (i=0; i<num_regs; i++) { + regs->beg[i] = regs->end[i] = -1; + } +} + +/* Match the pattern described by BUFP against STRING, which is of + SIZE. Start the match at index POS in STRING. In REGS, return the + indices of STRING that matched the entire BUFP->buffer and its + contained subexpressions. + + If bufp->fastmap is nonzero, then it had better be up to date. + + The reason that the data to match are specified as two components + which are to be regarded as concatenated is so this function can be + used directly on the contents of an Emacs buffer. + + -1 is returned if there is no match. -2 is returned if there is an + error (such as match stack overflow). Otherwise the value is the + length of the substring which was matched. */ + +int +re_match(bufp, string_arg, size, pos, regs) + struct re_pattern_buffer *bufp; + char *string_arg; + int size, pos; + struct re_registers *regs; +{ + register unsigned char *p = (unsigned char *) bufp->buffer; + + /* Pointer to beyond end of buffer. */ + register unsigned char *pend = p + bufp->used; + + unsigned num_regs = bufp->re_nsub; + + unsigned char *string = (unsigned char *) string_arg; + + register unsigned char *d, *dend; + register int mcnt; /* Multipurpose. */ + unsigned char *translate = (unsigned char *) bufp->translate; + unsigned is_a_jump_n = 0; + + /* Failure point stack. Each place that can handle a failure further + down the line pushes a failure point on this stack. It consists of + restart, regend, and reg_info for all registers corresponding to the + subexpressions we're currently inside, plus the number of such + registers, and, finally, two char *'s. The first char * is where to + resume scanning the pattern; the second one is where to resume + scanning the strings. If the latter is zero, the failure point is a + ``dummy''; if a failure happens and the failure point is a dummy, it + gets discarded and the next next one is tried. */ + + unsigned char **stackb; + unsigned char **stackp; + unsigned char **stacke; + + + /* Information on the contents of registers. These are pointers into + the input strings; they record just what was matched (on this + attempt) by a subexpression part of the pattern, that is, the + regnum-th regstart pointer points to where in the pattern we began + matching and the regnum-th regend points to right after where we + stopped matching the regnum-th subexpression. (The zeroth register + keeps track of what the whole pattern matches.) */ + + unsigned char **regstart = RE_TALLOC(num_regs, unsigned char*); + unsigned char **regend = RE_TALLOC(num_regs, unsigned char*); + + /* The is_active field of reg_info helps us keep track of which (possibly + nested) subexpressions we are currently in. The matched_something + field of reg_info[reg_num] helps us tell whether or not we have + matched any of the pattern so far this time through the reg_num-th + subexpression. These two fields get reset each time through any + loop their register is in. */ + + struct register_info *reg_info = RE_TALLOC(num_regs, struct register_info); + + /* The following record the register info as found in the above + variables when we find a match better than any we've seen before. + This happens as we backtrack through the failure points, which in + turn happens only if we have not yet matched the entire string. */ + + unsigned best_regs_set = 0; + unsigned char **best_regstart = RE_TALLOC(num_regs, unsigned char*); + unsigned char **best_regend = RE_TALLOC(num_regs, unsigned char*); + + if (regs) { + init_regs(regs, num_regs); + } + + + /* Initialize the stack. */ + stackb = RE_TALLOC(MAX_NUM_FAILURE_ITEMS * NFAILURES, unsigned char*); + stackp = stackb; + stacke = &stackb[MAX_NUM_FAILURE_ITEMS * NFAILURES]; + +#ifdef DEBUG_REGEX + fprintf (stderr, "Entering re_match(%s%s)\n", string1_arg, string2_arg); +#endif + + /* Initialize subexpression text positions to -1 to mark ones that no + \( or ( and \) or ) has been seen for. Also set all registers to + inactive and mark them as not having matched anything or ever + failed. */ + for (mcnt = 0; mcnt < num_regs; mcnt++) { + regstart[mcnt] = regend[mcnt] = (unsigned char *) (-1L); + IS_ACTIVE(reg_info[mcnt]) = 0; + MATCHED_SOMETHING(reg_info[mcnt]) = 0; + } + + /* Set up pointers to ends of strings. + Don't allow the second string to be empty unless both are empty. */ + + + /* `p' scans through the pattern as `d' scans through the data. `dend' + is the end of the input string that `d' points within. `d' is + advanced into the following input string whenever necessary, but + this happens before fetching; therefore, at the beginning of the + loop, `d' can be pointing at the end of a string, but it cannot + equal string2. */ + + d = string + pos, dend = string + size; + + + /* This loops over pattern commands. It exits by returning from the + function if match is complete, or it drops through if match fails + at this starting point in the input data. */ + + while (1) + { +#ifdef DEBUG_REGEX + fprintf(stderr, + "regex loop(%d): matching 0x%02d\n", + p - (unsigned char *) bufp->buffer, + *p); +#endif + is_a_jump_n = 0; + /* End of pattern means we might have succeeded. */ + if (p == pend) + { + /* If not end of string, try backtracking. Otherwise done. */ + if (d != dend) + { + if (stackp != stackb) + { + /* More failure points to try. */ + + /* If exceeds best match so far, save it. */ + if (! best_regs_set || (d > best_regend[0])) + { + best_regs_set = 1; + best_regend[0] = d; /* Never use regstart[0]. */ + + for (mcnt = 1; mcnt < num_regs; mcnt++) + { + best_regstart[mcnt] = regstart[mcnt]; + best_regend[mcnt] = regend[mcnt]; + } + } + goto fail; + } + /* If no failure points, don't restore garbage. */ + else if (best_regs_set) + { + restore_best_regs: + /* Restore best match. */ + d = best_regend[0]; + + for (mcnt = 0; mcnt < num_regs; mcnt++) + { + regstart[mcnt] = best_regstart[mcnt]; + regend[mcnt] = best_regend[mcnt]; + } + } + } + + /* If caller wants register contents data back, convert it + to indices. */ + if (regs) + { + regs->beg[0] = pos; + regs->end[0] = d - string; + for (mcnt = 1; mcnt < num_regs; mcnt++) + { + if (regend[mcnt] == (unsigned char *)(-1L)) + { + regs->beg[mcnt] = -1; + regs->end[mcnt] = -1; + continue; + } + regs->beg[mcnt] = regstart[mcnt] - string; + regs->end[mcnt] = regend[mcnt] - string; + } + } + FREE_VARIABLES(); + FREE_AND_RETURN(stackb, (d - pos - string)); + } + + /* Otherwise match next pattern command. */ +#ifdef SWITCH_ENUM_BUG + switch ((int)((enum regexpcode)*p++)) +#else + switch ((enum regexpcode)*p++) +#endif + { + + /* \( [or `(', as appropriate] is represented by start_memory, + \) by stop_memory. Both of those commands are followed by + a register number in the next byte. The text matched + within the \( and \) is recorded under that number. */ + case start_memory: + regstart[*p] = d; + IS_ACTIVE(reg_info[*p]) = 1; + MATCHED_SOMETHING(reg_info[*p]) = 0; + p++; + break; + + case stop_memory: + regend[*p] = d; + IS_ACTIVE(reg_info[*p]) = 0; + + /* If just failed to match something this time around with a sub- + expression that's in a loop, try to force exit from the loop. */ + if ((! MATCHED_SOMETHING(reg_info[*p]) + || (enum regexpcode) p[-3] == start_memory) + && (p + 1) != pend) + { + register unsigned char *p2 = p + 1; + mcnt = 0; + switch (*p2++) + { + case jump_n: + is_a_jump_n = 1; + case finalize_jump: + case maybe_finalize_jump: + case jump: + case dummy_failure_jump: + EXTRACT_NUMBER_AND_INCR(mcnt, p2); + if (is_a_jump_n) + p2 += 2; + break; + } + p2 += mcnt; + + /* If the next operation is a jump backwards in the pattern + to an on_failure_jump, exit from the loop by forcing a + failure after pushing on the stack the on_failure_jump's + jump in the pattern, and d. */ + if (mcnt < 0 && (enum regexpcode) *p2++ == on_failure_jump) + { + EXTRACT_NUMBER_AND_INCR(mcnt, p2); + PUSH_FAILURE_POINT(p2 + mcnt, d); + goto fail; + } + } + p++; + break; + + /* \<digit> has been turned into a `duplicate' command which is + followed by the numeric value of <digit> as the register number. */ + case duplicate: + { + int regno = *p++; /* Get which register to match against */ + register unsigned char *d2, *dend2; + + /* Where in input to try to start matching. */ + d2 = regstart[regno]; + + /* Where to stop matching; if both the place to start and + the place to stop matching are in the same string, then + set to the place to stop, otherwise, for now have to use + the end of the first string. */ + + dend2 = regend[regno]; + while (1) + { + /* At end of register contents => success */ + if (d2 == dend2) break; + + /* If necessary, advance to next segment in data. */ + PREFETCH; + + /* How many characters left in this segment to match. */ + mcnt = dend - d; + + /* Want how many consecutive characters we can match in + one shot, so, if necessary, adjust the count. */ + if (mcnt > dend2 - d2) + mcnt = dend2 - d2; + + /* Compare that many; failure if mismatch, else move + past them. */ + if (translate + ? memcmp_translate(d, d2, mcnt, translate) + : memcmp((char *)d, (char *)d2, mcnt)) + goto fail; + d += mcnt, d2 += mcnt; + } + } + break; + + case anychar: + PREFETCH; + /* Match anything but a newline, maybe even a null. */ + if (ismbchar(*d)) { + if (d + 1 == dend || d[1] == '\n' || d[1] == '\0') + goto fail; + SET_REGS_MATCHED; + d += 2; + break; + } + if ((translate ? translate[*d] : *d) == '\n' + || ((re_syntax_options & RE_DOT_NOT_NULL) + && (translate ? translate[*d] : *d) == '\000')) + goto fail; + SET_REGS_MATCHED; + d++; + break; + + case charset: + case charset_not: + { + int not; /* Nonzero for charset_not. */ + int half; /* 2 if need to match latter half of mbc */ + int c; + + PREFETCH; + c = (unsigned char)*d; + if (ismbchar(c)) { + if (d + 1 != dend) { + c <<= 8; + c |= (unsigned char)d[1]; + } + } + else if (translate) + c = (unsigned char)translate[c]; + + half = not = is_in_list(c, p); + if (*(p - 1) == (unsigned char)charset_not) { + not = !not; + } + + p += 1 + *p + 2 + EXTRACT_UNSIGNED(&p[1 + *p])*4; + + if (!not) goto fail; + SET_REGS_MATCHED; + + d++; + if (half != 2 && d != dend && c >= 1 << BYTEWIDTH) + d++; + break; + } + + case begline: + if (size == 0 + || d == string + || (d && d[-1] == '\n')) + break; + else + goto fail; + + case endline: + if (d == dend || *d == '\n') + break; + goto fail; + + /* `or' constructs are handled by starting each alternative with + an on_failure_jump that points to the start of the next + alternative. Each alternative except the last ends with a + jump to the joining point. (Actually, each jump except for + the last one really jumps to the following jump, because + tensioning the jumps is a hassle.) */ + + /* The start of a stupid repeat has an on_failure_jump that points + past the end of the repeat text. This makes a failure point so + that on failure to match a repetition, matching restarts past + as many repetitions have been found with no way to fail and + look for another one. */ + + /* A smart repeat is similar but loops back to the on_failure_jump + so that each repetition makes another failure point. */ + + case on_failure_jump: + on_failure: + EXTRACT_NUMBER_AND_INCR(mcnt, p); + PUSH_FAILURE_POINT(p + mcnt, d); + break; + + /* The end of a smart repeat has a maybe_finalize_jump back. + Change it either to a finalize_jump or an ordinary jump. */ + case maybe_finalize_jump: + EXTRACT_NUMBER_AND_INCR(mcnt, p); + { + register unsigned char *p2 = p; + /* Compare what follows with the beginning of the repeat. + If we can establish that there is nothing that they would + both match, we can change to finalize_jump. */ + while (p2 + 1 != pend + && (*p2 == (unsigned char)stop_memory + || *p2 == (unsigned char)start_memory)) + p2 += 2; /* Skip over reg number. */ + if (p2 == pend) + p[-3] = (unsigned char)finalize_jump; + else if (*p2 == (unsigned char)exactn + || *p2 == (unsigned char)endline) + { + register int c = *p2 == (unsigned char)endline ? '\n' : p2[2]; + register unsigned char *p1 = p + mcnt; + /* p1[0] ... p1[2] are an on_failure_jump. + Examine what follows that. */ + if (p1[3] == (unsigned char)exactn && p1[5] != c) + p[-3] = (unsigned char)finalize_jump; + else if (p1[3] == (unsigned char)charset + || p1[3] == (unsigned char)charset_not) { + int not; + if (ismbchar(c)) + c = c << 8 | p2[3]; + /* `is_in_list()' is TRUE if c would match */ + /* That means it is not safe to finalize. */ + not = is_in_list(c, p1 + 4); + if (p1[3] == (unsigned char)charset_not) + not = !not; + if (!not) + p[-3] = (unsigned char)finalize_jump; + } + } + } + p -= 2; /* Point at relative address again. */ + if (p[-1] != (unsigned char)finalize_jump) + { + p[-1] = (unsigned char)jump; + goto nofinalize; + } + /* Note fall through. */ + + /* The end of a stupid repeat has a finalize_jump back to the + start, where another failure point will be made which will + point to after all the repetitions found so far. */ + + /* Take off failure points put on by matching on_failure_jump + because didn't fail. Also remove the register information + put on by the on_failure_jump. */ + case finalize_jump: + POP_FAILURE_POINT(); + /* Note fall through. */ + + /* Jump without taking off any failure points. */ + case jump: + nofinalize: + EXTRACT_NUMBER_AND_INCR(mcnt, p); + p += mcnt; + break; + + case dummy_failure_jump: + /* Normally, the on_failure_jump pushes a failure point, which + then gets popped at finalize_jump. We will end up at + finalize_jump, also, and with a pattern of, say, `a+', we + are skipping over the on_failure_jump, so we have to push + something meaningless for finalize_jump to pop. */ + PUSH_FAILURE_POINT(0, 0); + goto nofinalize; + + + /* Have to succeed matching what follows at least n times. Then + just handle like an on_failure_jump. */ + case succeed_n: + EXTRACT_NUMBER(mcnt, p + 2); + /* Originally, this is how many times we HAVE to succeed. */ + if (mcnt) + { + mcnt--; + p += 2; + STORE_NUMBER_AND_INCR(p, mcnt); + } + else if (mcnt == 0) + { + p[2] = unused; + p[3] = unused; + goto on_failure; + } + else + { + fprintf(stderr, "regex: the succeed_n's n is not set.\n"); + exit(1); + } + break; + + case jump_n: + EXTRACT_NUMBER(mcnt, p + 2); + /* Originally, this is how many times we CAN jump. */ + if (mcnt) + { + mcnt--; + STORE_NUMBER(p + 2, mcnt); + goto nofinalize; /* Do the jump without taking off + any failure points. */ + } + /* If don't have to jump any more, skip over the rest of command. */ + else + p += 4; + break; + + case set_number_at: + { + register unsigned char *p1; + + EXTRACT_NUMBER_AND_INCR(mcnt, p); + p1 = p + mcnt; + EXTRACT_NUMBER_AND_INCR(mcnt, p); + STORE_NUMBER(p1, mcnt); + break; + } + + /* Ignore these. Used to ignore the n of succeed_n's which + currently have n == 0. */ + case unused: + break; + + case wordbound: + if (AT_WORD_BOUNDARY) + break; + goto fail; + + case notwordbound: + if (AT_WORD_BOUNDARY) + goto fail; + break; + + case wordchar: + PREFETCH; + if (!IS_A_LETTER(d)) + goto fail; + d++; + SET_REGS_MATCHED; + break; + + case notwordchar: + PREFETCH; + if (IS_A_LETTER(d)) + goto fail; + if (ismbchar(*d) && d + 1 != dend) + d++; + d++; + SET_REGS_MATCHED; + break; + + case exactn: + /* Match the next few pattern characters exactly. + mcnt is how many characters to match. */ + mcnt = *p++; + /* This is written out as an if-else so we don't waste time + testing `translate' inside the loop. */ + if (translate) + { + do + { + unsigned char c; + + PREFETCH; + c = *d++; + if (*p == 0xff) { + p++; + if (!--mcnt + || d == dend + || (unsigned char)*d++ != (unsigned char)*p++) + goto fail; + continue; + } + else if (ismbchar(c)) { + if (c != (unsigned char)*p++ + || !--mcnt /* redundant check if pattern was + compiled properly. */ + || d == dend + || (unsigned char)*d++ != (unsigned char)*p++) + goto fail; + continue; + } + /* compiled code translation needed for ruby */ + if ((unsigned char)translate[c] + != (unsigned char)translate[*p++]) + goto fail; + } + while (--mcnt); + } + else + { + do + { + PREFETCH; + if (*p == 0xff) {p++; mcnt--;} + if (*d++ != *p++) goto fail; + } + while (--mcnt); + } + SET_REGS_MATCHED; + break; + } + continue; /* Successfully executed one pattern command; keep going. */ + + /* Jump here if any matching operation fails. */ + fail: + if (stackp != stackb) + /* A restart point is known. Restart there and pop it. */ + { + short last_used_reg, this_reg; + + /* If this failure point is from a dummy_failure_point, just + skip it. */ + if (!stackp[-2]) + { + POP_FAILURE_POINT(); + goto fail; + } + + d = *--stackp; + p = *--stackp; + /* Restore register info. */ + last_used_reg = (long) *--stackp; + + /* Make the ones that weren't saved -1 or 0 again. */ + for (this_reg = num_regs - 1; this_reg > last_used_reg; this_reg--) + { + regend[this_reg] = (unsigned char *)(-1L); + regstart[this_reg] = (unsigned char *)(-1L); + IS_ACTIVE(reg_info[this_reg]) = 0; + MATCHED_SOMETHING(reg_info[this_reg]) = 0; + } + + /* And restore the rest from the stack. */ + for ( ; this_reg > 0; this_reg--) + { + reg_info[this_reg] = *(struct register_info *) *--stackp; + regend[this_reg] = *--stackp; + regstart[this_reg] = *--stackp; + } + } + else + break; /* Matching at this starting point really fails. */ + } + + if (best_regs_set) + goto restore_best_regs; + + FREE_AND_RETURN(stackb,(-1)); /* Failure to match. */ +} + + +static int +memcmp_translate(s1, s2, len, translate) + unsigned char *s1, *s2; + register int len; + unsigned char *translate; +{ + register unsigned char *p1 = s1, *p2 = s2, c; + while (len) + { + c = *p1++; + if (ismbchar(c)) { + if (c != *p2++ || !--len || *p1++ != *p2++) + return 1; + } + else + if (translate[c] != translate[*p2++]) + return 1; + len--; + } + return 0; +} + +void +re_copy_registers(regs1, regs2) + struct re_registers *regs1, *regs2; +{ + int i; + + if (regs1 == regs2) return; + if (regs1->allocated == 0) { + regs1->beg = TMALLOC(regs2->num_regs, int); + regs1->end = TMALLOC(regs2->num_regs, int); + regs1->allocated = regs2->num_regs; + } + else if (regs1->allocated < regs2->num_regs) { + TREALLOC(regs1->beg, regs2->num_regs, int); + TREALLOC(regs1->end, regs2->num_regs, int); + regs1->allocated = regs2->num_regs; + } + for (i=0; i<regs2->num_regs; i++) { + regs1->beg[i] = regs2->beg[i]; + regs1->end[i] = regs2->end[i]; + } + regs1->num_regs = regs2->num_regs; +} + +void +re_free_registers(regs) + struct re_registers *regs; +{ + if (regs->allocated == 0) return; + if (regs->beg) free(regs->beg); + if (regs->end) free(regs->end); +} |