lib/regextype.c

   1 /* regextype.c -- Decode the name of a regular expression syntax into am
   2                   option name.
   3
   4    Copyright 2005 Free Software Foundation, Inc.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 2, or (at your option)
   9    any later version.
  10
  11    This program 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
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software Foundation,
  18    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  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 "quotearg.h"
  33 #include "xalloc.h"
  34 #include "error.h"
  35
  36
  37 #if ENABLE_NLS
  38 # include <libintl.h>
  39 # define _(Text) gettext (Text)
  40 #else
  41 # define _(Text) Text
  42 #endif
  43 #ifdef gettext_noop
  44 # define N_(String) gettext_noop (String)
  45 #else
  46 /* See locate.c for explanation as to why not use (String) */
  47 # define N_(String) String
  48 #endif
  49
  50
  51
  52 struct tagRegexTypeMap
  53 {
  54   char *name;
  55   int   option_val;
  56 };
  57  struct tagRegexTypeMap regex_map[] =
  58   {
  59    { "emacs", RE_SYNTAX_EMACS },
  60    { "posix-awk", RE_SYNTAX_POSIX_AWK },
  61    { "posix-basic", RE_SYNTAX_POSIX_BASIC },
  62    { "posix-egrep", RE_SYNTAX_POSIX_EGREP },
  63    { "posix-extended", RE_SYNTAX_POSIX_EXTENDED }
  64    /* new and undocumented entries below... */
  65    ,{ "posix-minimal-basic", RE_SYNTAX_POSIX_MINIMAL_BASIC }
  66   };
  67 enum { N_REGEX_MAP_ENTRIES = sizeof(regex_map)/sizeof(regex_map[0]) };
  68
  69 int
  70 get_regex_type(const char *s)
  71 {
  72   unsigned i;
  73   size_t msglen;
  74   char *buf, *p;
  75
  76   msglen = 0u;
  77   for (i=0u; i<N_REGEX_MAP_ENTRIES; ++i)
  78     {
  79       if (0 == strcmp(regex_map[i].name, s))
  80         return regex_map[i].option_val;
  81       else
  82         msglen += strlen(quote(regex_map[i].name)) + 2u;
  83     }
  84
  85   /* We didn't find a match for the type of regular expression that the
  86    * user indicated they wanted.  Tell them what the options are.
  87    */
  88   p = buf = xmalloc(1u + msglen);
  89   for (i=0u; i<N_REGEX_MAP_ENTRIES; ++i)
  90     {
  91       if (i > 0u)
  92         {
  93           strcpy(p, ", ");
  94           p += 2;
  95         }
  96       p += sprintf(p, "%s", quote(regex_map[i].name));
  97     }
  98
  99   error(1, 0, _("Unknown regular expression type %s; valid types are %s."),
 100         quote(s),
 101         buf);
 102   /*NOTREACHED*/
 103   return -1;
 104 }
 105
 106
 107 const char *
 108 get_regex_type_name(int ix)
 109 {
 110   if (ix < N_REGEX_MAP_ENTRIES)
 111     return regex_map[ix].name;
 112   else
 113     return NULL;
 114 }
 115
 116 int
 117 get_regex_type_flags(int ix)
 118 {
 119   if (ix < N_REGEX_MAP_ENTRIES)
 120     return regex_map[ix].option_val;
 121   else
 122     return -1;
 123 }
 124