lib/regextype.c

   1
   2 /* regextype.c -- Decode the name of a regular expression syntax into am
   3                   option name.
   4
   5    Copyright 2005, 2010 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 # include <config.h>
  23
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <stdlib.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 struct tagRegexTypeMap
  51 {
  52   char *name;
  53   int  context;
  54   int   option_val;
  55 };
  56
  57 struct tagRegexTypeMap regex_map[] =
  58   {
  59    { "findutils-default",     CONTEXT_FINDUTILS, RE_SYNTAX_EMACS|RE_DOT_NEWLINE  },
  60    { "awk",                   CONTEXT_ALL,       RE_SYNTAX_AWK                   },
  61    { "egrep",                 CONTEXT_ALL,       RE_SYNTAX_EGREP                 },
  62    { "ed",                    CONTEXT_GENERIC,   RE_SYNTAX_ED                    },
  63    { "emacs",                 CONTEXT_ALL,       RE_SYNTAX_EMACS                 },
  64    { "gnu-awk",               CONTEXT_ALL,       RE_SYNTAX_GNU_AWK               },
  65    { "grep",                  CONTEXT_ALL,       RE_SYNTAX_GREP                  },
  66    { "posix-awk",             CONTEXT_ALL,       RE_SYNTAX_POSIX_AWK             },
  67    { "posix-basic",           CONTEXT_ALL,       RE_SYNTAX_POSIX_BASIC           },
  68    { "posix-egrep",           CONTEXT_ALL,       RE_SYNTAX_POSIX_EGREP           },
  69    { "posix-extended",        CONTEXT_ALL,       RE_SYNTAX_POSIX_EXTENDED        },
  70    { "posix-minimal-basic",   CONTEXT_GENERIC,   RE_SYNTAX_POSIX_MINIMAL_BASIC    },
  71    { "sed",                   CONTEXT_GENERIC,   RE_SYNTAX_SED                   },
  72    /*    ,{ "posix-common",   CONTEXT_GENERIC,  _RE_SYNTAX_POSIX_COMMON   } */
  73   };
  74 enum { N_REGEX_MAP_ENTRIES = sizeof (regex_map)/sizeof (regex_map[0]) };
  75
  76 int
  77 get_regex_type (const char *s)
  78 {
  79   unsigned i;
  80   size_t msglen;
  81   char *buf, *p;
  82
  83   msglen = 0u;
  84   for (i=0u; i<N_REGEX_MAP_ENTRIES; ++i)
  85     {
  86       if (0 == strcmp (regex_map[i].name, s))
  87         return regex_map[i].option_val;
  88       else
  89         msglen += strlen (quote (regex_map[i].name)) + 2u;
  90     }
  91
  92   /* We didn't find a match for the type of regular expression that the
  93    * user indicated they wanted.  Tell them what the options are.
  94    */
  95   p = buf = xmalloc (1u + msglen);
  96   for (i=0u; i<N_REGEX_MAP_ENTRIES; ++i)
  97     {
  98       if (i > 0u)
  99         {
 100           strcpy (p, ", ");
 101           p += 2;
 102         }
 103       p += sprintf (p, "%s", quote (regex_map[i].name));
 104     }
 105
 106   error (EXIT_FAILURE, 0,
 107          _("Unknown regular expression type %s; valid types are %s."),
 108          quote (s),
 109          buf);
 110   /*NOTREACHED*/
 111   return -1;
 112 }
 113
 114
 115 const char *
 116 get_regex_type_name (unsigned int ix)
 117 {
 118   if (ix < N_REGEX_MAP_ENTRIES)
 119     return regex_map[ix].name;
 120   else
 121     return NULL;
 122 }
 123
 124 int
 125 get_regex_type_flags (unsigned int ix)
 126 {
 127   if (ix < N_REGEX_MAP_ENTRIES)
 128     return regex_map[ix].option_val;
 129   else
 130     return -1;
 131 }
 132
 133 unsigned int get_regex_type_context (unsigned int ix)
 134 {
 135   if (ix < N_REGEX_MAP_ENTRIES)
 136     return regex_map[ix].context;
 137   else
 138     return 0u;
 139 }
 140
 141 int
 142 get_regex_type_synonym (unsigned int ix)
 143 {
 144   unsigned i;
 145   int flags;
 146
 147   if (ix >= N_REGEX_MAP_ENTRIES)
 148     return -1;
 149
 150   flags = regex_map[ix].option_val;
 151   for (i=0u; i<ix; ++i)
 152     {
 153       if (flags == regex_map[i].option_val)
 154         {
 155           return i;
 156         }
 157     }
 158   return -1;
 159 }