libguile/keywords.c

   1 /* Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004,
   2  *   2006, 2008, 2009, 2013 Free Software Foundation, Inc.
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public License
   6  * as published by the Free Software Foundation; either version 3 of
   7  * the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful, but
  10  * WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the Free Software
  16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  17  * 02110-1301 USA
  18  */
  19
  20
  21 \f
  22 #ifdef HAVE_CONFIG_H
  23 # include <config.h>
  24 #endif
  25
  26 #include <string.h>
  27 #include <stdarg.h>
  28
  29 #include "libguile/_scm.h"
  30 #include "libguile/async.h"
  31 #include "libguile/ports.h"
  32 #include "libguile/root.h"
  33 #include "libguile/smob.h"
  34 #include "libguile/hashtab.h"
  35
  36 #include "libguile/validate.h"
  37 #include "libguile/keywords.h"
  38 #include "libguile/strings.h"
  39
  40 \f
  41
  42 static SCM keyword_obarray;
  43
  44 scm_t_bits scm_tc16_keyword;
  45
  46 #define KEYWORDP(X)     (SCM_SMOB_PREDICATE (scm_tc16_keyword, (X)))
  47 #define KEYWORDSYM(X)   (SCM_SMOB_OBJECT (X))
  48
  49 static int
  50 keyword_print (SCM exp, SCM port, scm_print_state *pstate SCM_UNUSED)
  51 {
  52   scm_puts ("#:", port);
  53   scm_display (KEYWORDSYM (exp), port);
  54   return 1;
  55 }
  56
  57 SCM_DEFINE (scm_keyword_p, "keyword?", 1, 0, 0,
  58             (SCM obj),
  59             "Return @code{#t} if the argument @var{obj} is a keyword, else\n"
  60             "@code{#f}.")
  61 #define FUNC_NAME s_scm_keyword_p
  62 {
  63   return scm_from_bool (KEYWORDP (obj));
  64 }
  65 #undef FUNC_NAME
  66
  67 SCM_DEFINE (scm_symbol_to_keyword, "symbol->keyword", 1, 0, 0,
  68             (SCM symbol),
  69             "Return the keyword with the same name as @var{symbol}.")
  70 #define FUNC_NAME s_scm_symbol_to_keyword
  71 {
  72   SCM keyword;
  73
  74   SCM_ASSERT_TYPE (scm_is_symbol (symbol), symbol, 0, NULL, "symbol");
  75
  76   SCM_CRITICAL_SECTION_START;
  77   /* njrev: NEWSMOB and hashq_set_x can raise errors */
  78   keyword = scm_hashq_ref (keyword_obarray, symbol, SCM_BOOL_F);
  79   if (scm_is_false (keyword))
  80     {
  81       SCM_NEWSMOB (keyword, scm_tc16_keyword, SCM_UNPACK (symbol));
  82       scm_hashq_set_x (keyword_obarray, symbol, keyword);
  83     }
  84   SCM_CRITICAL_SECTION_END;
  85   return keyword;
  86 }
  87 #undef FUNC_NAME
  88
  89 SCM_DEFINE (scm_keyword_to_symbol, "keyword->symbol", 1, 0, 0,
  90             (SCM keyword),
  91             "Return the symbol with the same name as @var{keyword}.")
  92 #define FUNC_NAME s_scm_keyword_to_symbol
  93 {
  94   scm_assert_smob_type (scm_tc16_keyword, keyword);
  95   return KEYWORDSYM (keyword);
  96 }
  97 #undef FUNC_NAME
  98
  99 int
 100 scm_is_keyword (SCM val)
 101 {
 102   return KEYWORDP (val);
 103 }
 104
 105 SCM
 106 scm_from_locale_keyword (const char *name)
 107 {
 108   return scm_symbol_to_keyword (scm_from_locale_symbol (name));
 109 }
 110
 111 SCM
 112 scm_from_locale_keywordn (const char *name, size_t len)
 113 {
 114   return scm_symbol_to_keyword (scm_from_locale_symboln (name, len));
 115 }
 116
 117 SCM
 118 scm_from_latin1_keyword (const char *name)
 119 {
 120   return scm_symbol_to_keyword (scm_from_latin1_symbol (name));
 121 }
 122
 123 SCM
 124 scm_from_utf8_keyword (const char *name)
 125 {
 126   return scm_symbol_to_keyword (scm_from_utf8_symbol (name));
 127 }
 128
 129 SCM_SYMBOL (scm_keyword_argument_error, "keyword-argument-error");
 130
 131 void
 132 scm_c_bind_keyword_arguments (const char *subr, SCM rest,
 133                               scm_t_keyword_arguments_flags flags, ...)
 134 {
 135   va_list va;
 136
 137   if (SCM_UNLIKELY (!(flags & SCM_ALLOW_NON_KEYWORD_ARGUMENTS)
 138                     && scm_ilength (rest) % 2 != 0))
 139     scm_error (scm_keyword_argument_error,
 140                subr, "Odd length of keyword argument list",
 141                SCM_EOL, SCM_BOOL_F);
 142
 143   while (scm_is_pair (rest))
 144     {
 145       SCM kw_or_arg = SCM_CAR (rest);
 146       SCM tail = SCM_CDR (rest);
 147
 148       if (scm_is_keyword (kw_or_arg) && scm_is_pair (tail))
 149         {
 150           SCM kw;
 151           SCM *arg_p;
 152
 153           va_start (va, flags);
 154           for (;;)
 155             {
 156               kw = va_arg (va, SCM);
 157               if (SCM_UNBNDP (kw))
 158                 {
 159                   /* KW_OR_ARG is not in the list of expected keywords.  */
 160                   if (!(flags & SCM_ALLOW_OTHER_KEYS))
 161                     scm_error_scm (scm_keyword_argument_error,
 162                                    scm_from_locale_string (subr),
 163                                    scm_from_latin1_string
 164                                    ("Unrecognized keyword"),
 165                                    SCM_EOL, scm_list_1 (kw_or_arg));
 166                   break;
 167                 }
 168               arg_p = va_arg (va, SCM *);
 169               if (scm_is_eq (kw_or_arg, kw))
 170                 {
 171                   /* We found the matching keyword.  Store the
 172                      associated value and break out of the loop.  */
 173                   *arg_p = SCM_CAR (tail);
 174                   break;
 175                 }
 176             }
 177           va_end (va);
 178
 179           /* Advance REST.  */
 180           rest = SCM_CDR (tail);
 181         }
 182       else
 183         {
 184           /* The next argument is not a keyword, or is a singleton
 185              keyword at the end of REST.  */
 186           if (!(flags & SCM_ALLOW_NON_KEYWORD_ARGUMENTS))
 187             scm_error_scm (scm_keyword_argument_error,
 188                            scm_from_locale_string (subr),
 189                            scm_from_latin1_string ("Invalid keyword"),
 190                            SCM_EOL, scm_list_1 (kw_or_arg));
 191
 192            /* Advance REST.  */
 193            rest = tail;
 194         }
 195     }
 196 }
 197
 198 /* njrev: critical sections reviewed so far up to here */
 199 void
 200 scm_init_keywords ()
 201 {
 202   scm_tc16_keyword = scm_make_smob_type ("keyword", 0);
 203   scm_set_smob_print (scm_tc16_keyword, keyword_print);
 204
 205   keyword_obarray = scm_c_make_hash_table (0);
 206 #include "libguile/keywords.x"
 207 }
 208
 209
 210 /*
 211   Local Variables:
 212   c-file-style: "gnu"
 213   End:
 214 */