libguile/keywords.c

   1 /* Copyright (C) 1995,1996,1997,1998, 1999, 2000 Free Software Foundation, Inc.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2, or (at your option)
   6  * any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this software; see the file COPYING.  If not, write to
  15  * the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  16  * Boston, MA 02111-1307 USA
  17  *
  18  * As a special exception, the Free Software Foundation gives permission
  19  * for additional uses of the text contained in its release of GUILE.
  20  *
  21  * The exception is that, if you link the GUILE library with other files
  22  * to produce an executable, this does not by itself cause the
  23  * resulting executable to be covered by the GNU General Public License.
  24  * Your use of that executable is in no way restricted on account of
  25  * linking the GUILE library code into it.
  26  *
  27  * This exception does not however invalidate any other reasons why
  28  * the executable file might be covered by the GNU General Public License.
  29  *
  30  * This exception applies only to the code released by the
  31  * Free Software Foundation under the name GUILE.  If you copy
  32  * code from other Free Software Foundation releases into a copy of
  33  * GUILE, as the General Public License permits, the exception does
  34  * not apply to the code that you add in this way.  To avoid misleading
  35  * anyone as to the status of such modified files, you must delete
  36  * this exception notice from them.
  37  *
  38  * If you write modifications of your own for GUILE, it is your choice
  39  * whether to permit this exception to apply to your modifications.
  40  * If you do not wish that, delete this exception notice.  */
  41
  42 /* Software engineering face-lift by Greg J. Badros, 11-Dec-1999,
  43    gjb@cs.washington.edu, http://www.cs.washington.edu/homes/gjb */
  44
  45 \f
  46
  47 #include <stdio.h>
  48 #include <string.h>
  49
  50 #include "libguile/_scm.h"
  51 #include "libguile/ports.h"
  52 #include "libguile/root.h"
  53 #include "libguile/smob.h"
  54 #include "libguile/dump.h"
  55 #include "libguile/hashtab.h"
  56
  57 #include "libguile/validate.h"
  58 #include "libguile/keywords.h"
  59 \f
  60
  61 scm_bits_t scm_tc16_keyword;
  62
  63 static int
  64 keyword_print (SCM exp, SCM port, scm_print_state *pstate)
  65 {
  66   scm_puts ("#:", port);
  67   scm_puts(1 + SCM_SYMBOL_CHARS (SCM_CDR (exp)), port);
  68   return 1;
  69 }
  70
  71 static void
  72 keyword_dealloc (SCM obj, SCM dstate)
  73 {
  74   SCM sym = scm_keyword_dash_symbol (obj);
  75   scm_store_string (SCM_SYMBOL_CHARS (sym),
  76                     SCM_SYMBOL_LENGTH (sym),
  77                     dstate);
  78 }
  79
  80 static SCM
  81 keyword_alloc (SCM dstate)
  82 {
  83   int len;
  84   const char *mem = scm_restore_string (dstate, &len);
  85   SCM sym = scm_mem2symbol (mem, len);
  86   return scm_make_keyword_from_dash_symbol (sym);
  87 }
  88
  89 SCM_DEFINE (scm_make_keyword_from_dash_symbol, "make-keyword-from-dash-symbol", 1, 0, 0,
  90             (SCM symbol),
  91             "Make a keyword object from a @var{symbol} that starts with a dash.")
  92 #define FUNC_NAME s_scm_make_keyword_from_dash_symbol
  93 {
  94   SCM vcell;
  95
  96   SCM_ASSERT (SCM_SYMBOLP (symbol)
  97               && ('-' == SCM_SYMBOL_CHARS(symbol)[0]),
  98               symbol, SCM_ARG1, FUNC_NAME);
  99
 100   SCM_DEFER_INTS;
 101   vcell = scm_sym2ovcell_soft (symbol, scm_keyword_obarray);
 102   if (SCM_FALSEP (vcell))
 103     {
 104       SCM keyword;
 105       SCM_NEWSMOB (keyword, scm_tc16_keyword, SCM_UNPACK (symbol));
 106       scm_intern_symbol (scm_keyword_obarray, symbol);
 107       vcell = scm_sym2ovcell_soft (symbol, scm_keyword_obarray);
 108       SCM_SETCDR (vcell, keyword);
 109     }
 110   SCM_ALLOW_INTS;
 111   return SCM_CDR (vcell);
 112 }
 113 #undef FUNC_NAME
 114
 115 SCM
 116 scm_c_make_keyword (char *s)
 117 {
 118   char *buf = scm_must_malloc (strlen (s) + 2, "keyword");
 119   SCM symbol;
 120
 121   buf[0] = '-';
 122   strcpy (buf + 1, s);
 123   symbol = scm_str2symbol (buf);
 124   scm_must_free (buf);
 125   scm_done_free (strlen (s) + 2);
 126
 127   return scm_make_keyword_from_dash_symbol (symbol);
 128 }
 129
 130 SCM_DEFINE (scm_keyword_p, "keyword?", 1, 0, 0,
 131             (SCM obj),
 132             "Returns @code{#t} if the argument @var{obj} is a keyword, else @code{#f}.")
 133 #define FUNC_NAME s_scm_keyword_p
 134 {
 135   return SCM_BOOL(SCM_KEYWORDP (obj));
 136 }
 137 #undef FUNC_NAME
 138
 139
 140 SCM_DEFINE (scm_keyword_dash_symbol, "keyword-dash-symbol", 1, 0, 0,
 141             (SCM keyword),
 142             "Return the dash symbol for @var{keyword}.\n"
 143             "This is the inverse of @code{make-keyword-from-dash-symbol}.")
 144 #define FUNC_NAME s_scm_keyword_dash_symbol
 145 {
 146   SCM_VALIDATE_KEYWORD (1,keyword);
 147   return SCM_CDR (keyword);
 148 }
 149 #undef FUNC_NAME
 150
 151
 152
 153 void
 154 scm_init_keywords ()
 155 {
 156   scm_tc16_keyword = scm_make_smob_type ("keyword", 0);
 157   scm_set_smob_mark (scm_tc16_keyword, scm_markcdr);
 158   scm_set_smob_print (scm_tc16_keyword, keyword_print);
 159   scm_set_smob_dump (scm_tc16_keyword, 0, keyword_dealloc, 0);
 160   scm_set_smob_undump (scm_tc16_keyword, keyword_alloc, 0, 0);
 161
 162   scm_keyword_obarray = scm_c_make_hash_table (256);
 163 #ifndef SCM_MAGIC_SNARFER
 164 #include "libguile/keywords.x"
 165 #endif
 166 }
 167
 168
 169 /*
 170   Local Variables:
 171   c-file-style: "gnu"
 172   End:
 173 */