lib/regextype.c

   1
   2 /* regextype.c -- Decode the name of a regular expression syntax into am
   3                   option name.
   4
   5    Copyright 2005 Free Software Foundation, Inc.
   6
   7    This program is free software: you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation, either version 3 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  19 */
  20 /* Written by James Youngman, <jay@gnu.org>. */
  21
  22 #if HAVE_CONFIG_H
  23 # include <config.h>
  24 #endif
  25
  26 #include <string.h>
  27 #include <stdio.h>
  28
  29 #include "regextype.h"
  30 #include "regex.h"
  31 #include "quote.h"
  32 #include "xalloc.h"
  33 #include "error.h"
  34
  35
  36 #if ENABLE_NLS
  37 # include <libintl.h>
  38 # define _(Text) gettext (Text)
  39 #else
  40 # define _(Text) Text
  41 #endif
  42 #ifdef gettext_noop
  43 # define N_(String) gettext_noop (String)
  44 #else
  45 /* See locate.c for explanation as to why not use (String) */
  46 # define N_(String) String
  47 #endif
  48
  49
  50
  51 struct tagRegexTypeMap
  52 {
  53   char *name;
  54   int   option_val;
  55 };
  56
  57 struct tagRegexTypeMap regex_map[] =
  58   {
  59 #ifdef FINDUTILS
  60    { "findutils-default",      RE_SYNTAX_EMACS|RE_DOT_NEWLINE  },
  61 #endif
  62    { "awk",                    RE_SYNTAX_AWK                   },
  63    { "egrep",                  RE_SYNTAX_EGREP                 },
  64 #ifndef FINDUTILS
  65    { "ed",                     RE_SYNTAX_ED                    },
  66 #endif
  67    { "emacs",                  RE_SYNTAX_EMACS                 },
  68    { "gnu-awk",                RE_SYNTAX_GNU_AWK               },
  69    { "grep",                   RE_SYNTAX_GREP                  },
  70    { "posix-awk",              RE_SYNTAX_POSIX_AWK             },
  71    { "posix-basic",            RE_SYNTAX_POSIX_BASIC           },
  72    { "posix-egrep",            RE_SYNTAX_POSIX_EGREP           },
  73    { "posix-extended",         RE_SYNTAX_POSIX_EXTENDED        },
  74 #ifndef FINDUTILS
  75    { "posix-minimal-basic",   RE_SYNTAX_POSIX_MINIMAL_BASIC    },
  76    { "sed",                    RE_SYNTAX_SED                   },
  77    /*    ,{ "posix-common",   _RE_SYNTAX_POSIX_COMMON   } */
  78 #endif
  79   };
  80 enum { N_REGEX_MAP_ENTRIES = sizeof(regex_map)/sizeof(regex_map[0]) };
  81
  82 int
  83 get_regex_type(const char *s)
  84 {
  85   unsigned i;
  86   size_t msglen;
  87   char *buf, *p;
  88
  89   msglen = 0u;
  90   for (i=0u; i<N_REGEX_MAP_ENTRIES; ++i)
  91     {
  92       if (0 == strcmp(regex_map[i].name, s))
  93         return regex_map[i].option_val;
  94       else
  95         msglen += strlen(quote(regex_map[i].name)) + 2u;
  96     }
  97
  98   /* We didn't find a match for the type of regular expression that the
  99    * user indicated they wanted.  Tell them what the options are.
 100    */
 101   p = buf = xmalloc(1u + msglen);
 102   for (i=0u; i<N_REGEX_MAP_ENTRIES; ++i)
 103     {
 104       if (i > 0u)
 105         {
 106           strcpy(p, ", ");
 107           p += 2;
 108         }
 109       p += sprintf(p, "%s", quote(regex_map[i].name));
 110     }
 111
 112   error(1, 0, _("Unknown regular expression type %s; valid types are %s."),
 113         quote(s),
 114         buf);
 115   /*NOTREACHED*/
 116   return -1;
 117 }
 118
 119
 120 const char *
 121 get_regex_type_name(unsigned int ix)
 122 {
 123   if (ix < N_REGEX_MAP_ENTRIES)
 124     return regex_map[ix].name;
 125   else
 126     return NULL;
 127 }
 128
 129 int
 130 get_regex_type_flags(unsigned int ix)
 131 {
 132   if (ix < N_REGEX_MAP_ENTRIES)
 133     return regex_map[ix].option_val;
 134   else
 135     return -1;
 136 }
 137
 138
 139 int get_regex_type_synonym(unsigned int ix)
 140 {
 141   unsigned i;
 142   int flags;
 143
 144   if (ix >= N_REGEX_MAP_ENTRIES)
 145     return -1;
 146
 147   flags = regex_map[ix].option_val;
 148   for (i=0u; i<ix; ++i)
 149     {
 150       if (flags == regex_map[i].option_val)
 151         {
 152           return i;
 153         }
 154     }
 155   return -1;
 156 }