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Diffstat (limited to 'src/regex.h')
| -rw-r--r-- | src/regex.h | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/src/regex.h b/src/regex.h new file mode 100644 index 00000000000..7462e51d821 --- /dev/null +++ b/src/regex.h @@ -0,0 +1,184 @@ +/* Definitions for data structures callers pass the regex library. + Copyright (C) 1985 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. + +In other words, you are welcome to use, share and improve this program. +You are forbidden to forbid anyone else to use, share and improve +what you give them. Help stamp out software-hoarding! */ + + +/* Define number of parens for which we record the beginnings and ends. + This affects how much space the `struct re_registers' type takes up. */ +#ifndef RE_NREGS +#define RE_NREGS 10 +#endif + +/* These bits are used in the obscure_syntax variable to choose among + alternative regexp syntaxes. */ + +/* 1 means plain parentheses serve as grouping, and backslash + parentheses are needed for literal searching. + 0 means backslash-parentheses are grouping, and plain parentheses + are for literal searching. */ +#define RE_NO_BK_PARENS 1 + +/* 1 means plain | serves as the "or"-operator, and \| is a literal. + 0 means \| serves as the "or"-operator, and | is a literal. */ +#define RE_NO_BK_VBAR 2 + +/* 0 means plain + or ? serves as an operator, and \+, \? are literals. + 1 means \+, \? are operators and plain +, ? are literals. */ +#define RE_BK_PLUS_QM 4 + +/* 1 means | binds tighter than ^ or $. + 0 means the contrary. */ +#define RE_TIGHT_VBAR 8 + +/* 1 means treat \n as an _OR operator + 0 means treat it as a normal character */ +#define RE_NEWLINE_OR 16 + +/* 0 means that a special characters (such as *, ^, and $) always have + their special meaning regardless of the surrounding context. + 1 means that special characters may act as normal characters in some + contexts. Specifically, this applies to: + ^ - only special at the beginning, or after ( or | + $ - only special at the end, or before ) or | + *, +, ? - only special when not after the beginning, (, or | */ +#define RE_CONTEXT_INDEP_OPS 32 + +/* Now define combinations of bits for the standard possibilities. */ +#define RE_SYNTAX_AWK (RE_NO_BK_PARENS | RE_NO_BK_VBAR | RE_CONTEXT_INDEP_OPS) +#define RE_SYNTAX_EGREP (RE_SYNTAX_AWK | RE_NEWLINE_OR) +#define RE_SYNTAX_GREP (RE_BK_PLUS_QM | RE_NEWLINE_OR) +#define RE_SYNTAX_EMACS 0 + +/* This data structure is used to represent a compiled pattern. */ + +struct re_pattern_buffer + { + char *buffer; /* Space holding the compiled pattern commands. */ + int allocated; /* Size of space that buffer points to */ + int used; /* Length of portion of buffer actually occupied */ + char *fastmap; /* Pointer to fastmap, if any, or zero if none. */ + /* re_search uses the fastmap, if there is one, + to skip quickly over totally implausible characters */ + char *translate; /* Translate table to apply to all characters before comparing. + Or zero for no translation. + The translation is applied to a pattern when it is compiled + and to data when it is matched. */ + char fastmap_accurate; + /* Set to zero when a new pattern is stored, + set to one when the fastmap is updated from it. */ + char can_be_null; /* Set to one by compiling fastmap + if this pattern might match the null string. + It does not necessarily match the null string + in that case, but if this is zero, it cannot. + 2 as value means can match null string + but at end of range or before a character + listed in the fastmap. */ + }; + +/* Structure to store "register" contents data in. + + Pass the address of such a structure as an argument to re_match, etc., + if you want this information back. + + start[i] and end[i] record the string matched by \( ... \) grouping i, + for i from 1 to RE_NREGS - 1. + start[0] and end[0] record the entire string matched. */ + +struct re_registers + { + int start[RE_NREGS]; + int end[RE_NREGS]; + }; + +/* 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 whatever for its arguments. + Zero-bytes may appear in the compiled regular expression. */ + +enum regexpcode + { + unused, + exactn, /* followed by one byte giving n, and then by n literal bytes */ + begline, /* fails unless at beginning of line */ + endline, /* fails 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. */ + anychar, /* matches any one character */ + charset, /* matches any one char belonging to specified set. + First following byte is # bitmap bytes. + Then come bytes for a bit-map 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, /* similar but match any character that is NOT one of those specified */ + start_memory, /* starts remembering the text that is matched + and stores it in a memory register. + followed by one byte containing the register number. + Register numbers must be in the range 0 through NREGS. */ + stop_memory, /* stops remembering the text that is matched + and stores it in a memory register. + followed by one byte containing the register number. + Register numbers must be in the range 0 through NREGS. */ + duplicate, /* match a duplicate of something remembered. + Followed by one byte containing the index of the memory register. */ + before_dot, /* Succeeds if before dot */ + at_dot, /* Succeeds if at dot */ + after_dot, /* Succeeds if after dot */ + begbuf, /* Succeeds if at beginning of buffer */ + endbuf, /* Succeeds if at end of buffer */ + wordchar, /* Matches any word-constituent character */ + notwordchar, /* Matches any char that is not a word-constituent */ + wordbeg, /* Succeeds if at word beginning */ + wordend, /* Succeeds if at word end */ + wordbound, /* Succeeds if at a word boundary */ + notwordbound, /* Succeeds if not at a word boundary */ + syntaxspec, /* Matches any character whose syntax is specified. + followed by a byte which contains a syntax code, Sword or such like */ + notsyntaxspec /* Matches any character whose syntax differs from the specified. */ + }; + +extern char *re_compile_pattern (); +/* Is this really advertised? */ +extern void re_compile_fastmap (); +extern int re_search (), re_search_2 (); +extern int re_match (), re_match_2 (); + +/* 4.2 bsd compatibility (yuck) */ +extern char *re_comp (); +extern int re_exec (); + +#ifdef SYNTAX_TABLE +extern char *re_syntax_table; +#endif |