regexp.h
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- /* Copyright (C) 1996, 1997, 1998, 1999, 2004 Free Software Foundation, Inc.
- This file is part of the GNU C Library.
- Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
- The GNU C Library is free software; you can redistribute it and/or
- modify it under the terms of the GNU Lesser General Public
- License as published by the Free Software Foundation; either
- version 2.1 of the License, or (at your option) any later version.
- The GNU C Library 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
- Lesser General Public License for more details.
- You should have received a copy of the GNU Lesser General Public
- License along with the GNU C Library; if not, write to the Free
- Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
- 02111-1307 USA. */
- #ifndef _REGEXP_H
- #define _REGEXP_H 1
- /* The contents of this header file was first standardized in X/Open
- System Interface and Headers Issue 2, originally coming from SysV.
- In issue 4, version 2, it is marked as TO BE WITDRAWN, and it has
- been withdrawn in SUSv3.
- This code shouldn't be used in any newly written code. It is
- included only for compatibility reasons. Use the POSIX definition
- in <regex.h> for portable applications and a reasonable interface. */
- #include <features.h>
- #include <alloca.h>
- #include <regex.h>
- #include <stdlib.h>
- #include <string.h>
- /* The implementation provided here emulates the needed functionality
- by mapping to the POSIX regular expression matcher. The interface
- for the here included function is weird (this really is a harmless
- word).
- The user has to provide six macros before this header file can be
- included:
- INIT Declarations vor variables which can be used by the
- other macros.
- GETC() Return the value of the next character in the regular
- expression pattern. Successive calls should return
- successive characters.
- PEEKC() Return the value of the next character in the regular
- expression pattern. Immediately successive calls to
- PEEKC() should return the same character which should
- also be the next character returned by GETC().
- UNGETC(c) Cause `c' to be returned by the next call to GETC() and
- PEEKC().
- RETURN(ptr) Used for normal exit of the `compile' function. `ptr'
- is a pointer to the character after the last character of
- the compiled regular expression.
- ERROR(val) Used for abnormal return from `compile'. `val' is the
- error number. The error codes are:
- 11 Range endpoint too large.
- 16 Bad number.
- 25 digit out of range.
- 36 Illegal or missing delimiter.
- 41 No remembered search string.
- 42 ( ) imbalance.
- 43 Too many (.
- 44 More tan two numbers given in { }.
- 45 } expected after .
- 46 First number exceeds second in { }.
- 49 [ ] imbalance.
- 50 Regular expression overflow.
- */
- __BEGIN_DECLS
- /* Interface variables. They contain the results of the successful
- calls to `setp' and `advance'. */
- extern char *loc1;
- extern char *loc2;
- /* The use of this variable in the `advance' function is not
- supported. */
- extern char *locs;
- #ifndef __DO_NOT_DEFINE_COMPILE
- /* Get and compile the user supplied pattern up to end of line or
- string or until EOF is seen, whatever happens first. The result is
- placed in the buffer starting at EXPBUF and delimited by ENDBUF.
- This function cannot be defined in the libc itself since it depends
- on the macros. */
- char *
- compile (char *__restrict instring, char *__restrict expbuf,
- __const char *__restrict endbuf, int eof)
- {
- char *__input_buffer = NULL;
- size_t __input_size = 0;
- size_t __current_size = 0;
- int __ch;
- int __error;
- INIT
- /* Align the expression buffer according to the needs for an object
- of type `regex_t'. Then check for minimum size of the buffer for
- the compiled regular expression. */
- regex_t *__expr_ptr;
- # if defined __GNUC__ && __GNUC__ >= 2
- const size_t __req = __alignof__ (regex_t *);
- # else
- /* How shall we find out? We simply guess it and can change it is
- this really proofs to be wrong. */
- const size_t __req = 8;
- # endif
- expbuf += __req;
- expbuf -= (expbuf - ((char *) 0)) % __req;
- if (endbuf < expbuf + sizeof (regex_t))
- {
- ERROR (50);
- }
- __expr_ptr = (regex_t *) expbuf;
- /* The remaining space in the buffer can be used for the compiled
- pattern. */
- __expr_ptr->buffer = expbuf + sizeof (regex_t);
- __expr_ptr->allocated = endbuf - (char *) __expr_ptr->buffer;
- while ((__ch = (GETC ())) != eof)
- {
- if (__ch == ' ' || __ch == 'n')
- {
- UNGETC (__ch);
- break;
- }
- if (__current_size + 1 >= __input_size)
- {
- size_t __new_size = __input_size ? 2 * __input_size : 128;
- char *__new_room = (char *) alloca (__new_size);
- /* See whether we can use the old buffer. */
- if (__new_room + __new_size == __input_buffer)
- {
- __input_size += __new_size;
- __input_buffer = (char *) memcpy (__new_room, __input_buffer,
- __current_size);
- }
- else if (__input_buffer + __input_size == __new_room)
- __input_size += __new_size;
- else
- {
- __input_size = __new_size;
- __input_buffer = (char *) memcpy (__new_room, __input_buffer,
- __current_size);
- }
- }
- __input_buffer[__current_size++] = __ch;
- }
- __input_buffer[__current_size++] = ' ';
- /* Now compile the pattern. */
- __error = regcomp (__expr_ptr, __input_buffer, REG_NEWLINE);
- if (__error != 0)
- /* Oh well, we have to translate POSIX error codes. */
- switch (__error)
- {
- case REG_BADPAT:
- case REG_ECOLLATE:
- case REG_ECTYPE:
- case REG_EESCAPE:
- case REG_BADRPT:
- case REG_EEND:
- case REG_ERPAREN:
- default:
- /* There is no matching error code. */
- RETURN (36);
- case REG_ESUBREG:
- RETURN (25);
- case REG_EBRACK:
- RETURN (49);
- case REG_EPAREN:
- RETURN (42);
- case REG_EBRACE:
- RETURN (44);
- case REG_BADBR:
- RETURN (46);
- case REG_ERANGE:
- RETURN (11);
- case REG_ESPACE:
- case REG_ESIZE:
- ERROR (50);
- }
- /* Everything is ok. */
- RETURN ((char *) (__expr_ptr->buffer + __expr_ptr->used));
- }
- #endif
- /* Find the next match in STRING. The compiled regular expression is
- found in the buffer starting at EXPBUF. `loc1' will return the
- first character matched and `loc2' points to the next unmatched
- character. */
- extern int step (__const char *__restrict __string,
- __const char *__restrict __expbuf) __THROW;
- /* Match the beginning of STRING with the compiled regular expression
- in EXPBUF. If the match is successful `loc2' will contain the
- position of the first unmatched character. */
- extern int advance (__const char *__restrict __string,
- __const char *__restrict __expbuf) __THROW;
- __END_DECLS
- #endif /* regexp.h */