misc/regexp.c

   1 /* Compatibility symbols for the obsolete <regexp.h> interface.
   2    Copyright (C) 1996-2018 Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, see
  18    <http://www.gnu.org/licenses/>.  */
  19
  20 /* regexp.h now contains only an #error directive, so it cannot be
  21    used in this file.
  22
  23    The function that would produce an 'expbuf' to use as the second
  24    argument to 'step' and 'advance' was defined only in regexp.h,
  25    as its definition depended on macros defined by the user.  */
  26
  27 #include <regex.h>
  28 #include <shlib-compat.h>
  29
  30 #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_23)
  31
  32 /* Define the variables used for the interface.  Avoid .symver on common
  33    symbol, which just creates a new common symbol, not an alias.  */
  34 char *loc1 __attribute__ ((nocommon));
  35 char *loc2 __attribute__ ((nocommon));
  36 compat_symbol (libc, loc1, loc1, GLIBC_2_0);
  37 compat_symbol (libc, loc2, loc2, GLIBC_2_0);
  38
  39 /* Although we do not support the use we define this variable as well.  */
  40 char *locs __attribute__ ((nocommon));
  41 compat_symbol (libc, locs, locs, GLIBC_2_0);
  42
  43
  44 /* Find the next match in STRING.  The compiled regular expression is
  45    found in the buffer starting at EXPBUF.  `loc1' will return the
  46    first character matched and `loc2' points to the next unmatched
  47    character.  */
  48 int
  49 weak_function attribute_compat_text_section
  50 step (const char *string, const char *expbuf)
  51 {
  52   regmatch_t match;     /* We only need info about the full match.  */
  53
  54   expbuf += __alignof (regex_t *);
  55   expbuf -= (expbuf - ((const char *) 0)) % __alignof__ (regex_t *);
  56
  57   if (__regexec ((const regex_t *) expbuf, string, 1, &match, REG_NOTEOL)
  58       == REG_NOMATCH)
  59     return 0;
  60
  61   loc1 = (char *) string + match.rm_so;
  62   loc2 = (char *) string + match.rm_eo;
  63   return 1;
  64 }
  65 compat_symbol (libc, step, step, GLIBC_2_0);
  66
  67
  68 /* Match the beginning of STRING with the compiled regular expression
  69    in EXPBUF.  If the match is successful `loc2' will contain the
  70    position of the first unmatched character.  */
  71 int
  72 weak_function attribute_compat_text_section
  73 advance (const char *string, const char *expbuf)
  74 {
  75   regmatch_t match;     /* We only need info about the full match.  */
  76
  77   expbuf += __alignof__ (regex_t *);
  78   expbuf -= (expbuf - ((const char *) 0)) % __alignof__ (regex_t *);
  79
  80   if (__regexec ((const regex_t *) expbuf, string, 1, &match, REG_NOTEOL)
  81       == REG_NOMATCH
  82       /* We have to check whether the check is at the beginning of the
  83          buffer.  */
  84       || match.rm_so != 0)
  85     return 0;
  86
  87   loc2 = (char *) string + match.rm_eo;
  88   return 1;
  89 }
  90 compat_symbol (libc, advance, advance, GLIBC_2_0);
  91
  92
  93 #endif /* SHLIB_COMPAT (2.0, 2.23) */