libguile/srcprop.c

   1 /* Copyright (C) 1995,1996,1997,1998,1999,2000,2001,2002, 2006, 2008, 2009, 2010 Free Software Foundation
   2  *
   3  * This library is free software; you can redistribute it and/or
   4  * modify it under the terms of the GNU Lesser General Public License
   5  * as published by the Free Software Foundation; either version 3 of
   6  * the License, or (at your option) any later version.
   7  *
   8  * This library is distributed in the hope that it will be useful, but
   9  * WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  11  * Lesser General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU Lesser General Public
  14  * License along with this library; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  16  * 02110-1301 USA
  17  */
  18
  19
  20 \f
  21 #ifdef HAVE_CONFIG_H
  22 # include <config.h>
  23 #endif
  24
  25 #include <errno.h>
  26
  27 #include "libguile/_scm.h"
  28 #include "libguile/async.h"
  29 #include "libguile/smob.h"
  30 #include "libguile/alist.h"
  31 #include "libguile/debug.h"
  32 #include "libguile/hashtab.h"
  33 #include "libguile/hash.h"
  34 #include "libguile/ports.h"
  35 #include "libguile/root.h"
  36 #include "libguile/weaks.h"
  37 #include "libguile/gc.h"
  38
  39 #include "libguile/validate.h"
  40 #include "libguile/srcprop.h"
  41 \f
  42 /* {Source Properties}
  43  *
  44  * Properties of source list expressions.
  45  * Four of these have special meaning:
  46  *
  47  * filename    string   The name of the source file.
  48  * copy        list     A copy of the list expression.
  49  * line        integer  The source code line number.
  50  * column      integer  The source code column number.
  51  *
  52  * Most properties above can be set by the reader.
  53  *
  54  */
  55
  56 SCM_GLOBAL_SYMBOL (scm_sym_filename, "filename");
  57 SCM_GLOBAL_SYMBOL (scm_sym_copy, "copy");
  58 SCM_GLOBAL_SYMBOL (scm_sym_line, "line");
  59 SCM_GLOBAL_SYMBOL (scm_sym_column, "column");
  60 SCM scm_source_whash;
  61
  62
  63
  64 /*
  65  *  Source properties are stored as double cells with the
  66  *  following layout:
  67
  68  * car = tag
  69  * cbr = pos
  70  * ccr = copy
  71  * cdr = alist
  72  */
  73
  74 #define SRCPROPSP(p) (SCM_SMOB_PREDICATE (scm_tc16_srcprops, (p)))
  75 #define SRCPROPPOS(p) (SCM_SMOB_DATA(p))
  76 #define SRCPROPLINE(p) (SRCPROPPOS(p) >> 12)
  77 #define SRCPROPCOL(p) (SRCPROPPOS(p) & 0x0fffL)
  78 #define SRCPROPCOPY(p) (SCM_SMOB_OBJECT_2(p))
  79 #define SRCPROPALIST(p) (SCM_SMOB_OBJECT_3(p))
  80 #define SRCPROPMAKPOS(l, c) (((l) << 12) + (c))
  81 #define SETSRCPROPPOS(p, l, c) (SCM_SET_SMOB_DATA_1 (p, SRCPROPMAKPOS (l, c)))
  82 #define SETSRCPROPLINE(p, l) SETSRCPROPPOS (p, l, SRCPROPCOL (p))
  83 #define SETSRCPROPCOL(p, c) SETSRCPROPPOS (p, SRCPROPLINE (p), c)
  84 #define SETSRCPROPCOPY(p, c) (SCM_SET_SMOB_OBJECT_2 (p, c))
  85 #define SETSRCPROPALIST(p, l) (SCM_SET_SMOB_OBJECT_3 (p, l))
  86
  87
  88 static SCM scm_srcprops_to_alist (SCM obj);
  89
  90
  91 scm_t_bits scm_tc16_srcprops;
  92
  93 static int
  94 srcprops_print (SCM obj, SCM port, scm_print_state *pstate)
  95 {
  96   int writingp = SCM_WRITINGP (pstate);
  97   scm_puts ("#<srcprops ", port);
  98   SCM_SET_WRITINGP (pstate, 1);
  99   scm_iprin1 (scm_srcprops_to_alist (obj), port, pstate);
 100   SCM_SET_WRITINGP (pstate, writingp);
 101   scm_putc ('>', port);
 102   return 1;
 103 }
 104
 105
 106 /*
 107  * We remember the last file name settings, so we can share that alist
 108  * entry.  This works because scm_set_source_property_x does not use
 109  * assoc-set! for modifying the alist.
 110  *
 111  * This variable contains a protected cons, whose cdr is the cached
 112  * alist
 113  */
 114 static SCM scm_last_alist_filename;
 115
 116 SCM
 117 scm_make_srcprops (long line, int col, SCM filename, SCM copy, SCM alist)
 118 {
 119   if (!SCM_UNBNDP (filename))
 120     {
 121       SCM old_alist = alist;
 122
 123       /*
 124         have to extract the acons, and operate on that, for
 125         thread safety.
 126        */
 127       SCM last_acons = SCM_CDR (scm_last_alist_filename);
 128       if (old_alist == SCM_EOL
 129           && SCM_CDAR (last_acons) == filename)
 130         {
 131           alist = last_acons;
 132         }
 133       else
 134         {
 135           alist = scm_acons (scm_sym_filename, filename, alist);
 136           if (old_alist == SCM_EOL)
 137             SCM_SETCDR (scm_last_alist_filename, alist);
 138         }
 139     }
 140
 141   SCM_RETURN_NEWSMOB3 (scm_tc16_srcprops,
 142                        SRCPROPMAKPOS (line, col),
 143                        copy,
 144                        alist);
 145 }
 146
 147
 148 static SCM
 149 scm_srcprops_to_alist (SCM obj)
 150 {
 151   SCM alist = SRCPROPALIST (obj);
 152   if (!SCM_UNBNDP (SRCPROPCOPY (obj)))
 153     alist = scm_acons (scm_sym_copy, SRCPROPCOPY (obj), alist);
 154   alist = scm_acons (scm_sym_column, scm_from_int (SRCPROPCOL (obj)), alist);
 155   alist = scm_acons (scm_sym_line, scm_from_int (SRCPROPLINE (obj)), alist);
 156   return alist;
 157 }
 158
 159 SCM_DEFINE (scm_source_properties, "source-properties", 1, 0, 0,
 160             (SCM obj),
 161             "Return the source property association list of @var{obj}.")
 162 #define FUNC_NAME s_scm_source_properties
 163 {
 164   SCM p;
 165   SCM_VALIDATE_NIM (1, obj);
 166   p = scm_hashq_ref (scm_source_whash, obj, SCM_EOL);
 167   if (SRCPROPSP (p))
 168     return scm_srcprops_to_alist (p);
 169   else
 170     /* list from set-source-properties!, or SCM_EOL for not found */
 171     return p;
 172 }
 173 #undef FUNC_NAME
 174
 175 /* Perhaps this procedure should look through an alist
 176    and try to make a srcprops-object...? */
 177 SCM_DEFINE (scm_set_source_properties_x, "set-source-properties!", 2, 0, 0,
 178             (SCM obj, SCM alist),
 179             "Install the association list @var{alist} as the source property\n"
 180             "list for @var{obj}.")
 181 #define FUNC_NAME s_scm_set_source_properties_x
 182 {
 183   SCM handle;
 184   SCM_VALIDATE_NIM (1, obj);
 185   handle = scm_hashq_create_handle_x (scm_source_whash, obj, alist);
 186   SCM_SETCDR (handle, alist);
 187   return alist;
 188 }
 189 #undef FUNC_NAME
 190
 191 SCM_DEFINE (scm_source_property, "source-property", 2, 0, 0,
 192             (SCM obj, SCM key),
 193             "Return the source property specified by @var{key} from\n"
 194             "@var{obj}'s source property list.")
 195 #define FUNC_NAME s_scm_source_property
 196 {
 197   SCM p;
 198   SCM_VALIDATE_NIM (1, obj);
 199   p = scm_hashq_ref (scm_source_whash, obj, SCM_EOL);
 200   if (!SRCPROPSP (p))
 201     goto alist;
 202   if (scm_is_eq (scm_sym_line, key))
 203     p = scm_from_int (SRCPROPLINE (p));
 204   else if (scm_is_eq (scm_sym_column, key))
 205     p = scm_from_int (SRCPROPCOL (p));
 206   else if (scm_is_eq (scm_sym_copy, key))
 207     p = SRCPROPCOPY (p);
 208   else
 209     {
 210       p = SRCPROPALIST (p);
 211     alist:
 212       p = scm_assoc (key, p);
 213       return (SCM_NIMP (p) ? SCM_CDR (p) : SCM_BOOL_F);
 214     }
 215   return SCM_UNBNDP (p) ? SCM_BOOL_F : p;
 216 }
 217 #undef FUNC_NAME
 218
 219 SCM_DEFINE (scm_set_source_property_x, "set-source-property!", 3, 0, 0,
 220             (SCM obj, SCM key, SCM datum),
 221             "Set the source property of object @var{obj}, which is specified by\n"
 222             "@var{key} to @var{datum}.  Normally, the key will be a symbol.")
 223 #define FUNC_NAME s_scm_set_source_property_x
 224 {
 225   scm_whash_handle h;
 226   SCM p;
 227   SCM_VALIDATE_NIM (1, obj);
 228   h = scm_whash_get_handle (scm_source_whash, obj);
 229   if (SCM_WHASHFOUNDP (h))
 230     p = SCM_WHASHREF (scm_source_whash, h);
 231   else
 232     {
 233       h = scm_whash_create_handle (scm_source_whash, obj);
 234       p = SCM_EOL;
 235     }
 236
 237   if (scm_is_eq (scm_sym_line, key))
 238     {
 239       if (SRCPROPSP (p))
 240         SETSRCPROPLINE (p, scm_to_int (datum));
 241       else
 242         SCM_WHASHSET (scm_source_whash, h,
 243                       scm_make_srcprops (scm_to_int (datum), 0,
 244                                          SCM_UNDEFINED, SCM_UNDEFINED, p));
 245     }
 246   else if (scm_is_eq (scm_sym_column, key))
 247     {
 248       if (SRCPROPSP (p))
 249         SETSRCPROPCOL (p, scm_to_int (datum));
 250       else
 251         SCM_WHASHSET (scm_source_whash, h,
 252                       scm_make_srcprops (0, scm_to_int (datum),
 253                                          SCM_UNDEFINED, SCM_UNDEFINED, p));
 254     }
 255   else if (scm_is_eq (scm_sym_copy, key))
 256     {
 257       if (SRCPROPSP (p))
 258         SETSRCPROPCOPY (p, datum);
 259       else
 260         SCM_WHASHSET (scm_source_whash, h, scm_make_srcprops (0, 0, SCM_UNDEFINED, datum, p));
 261     }
 262   else
 263     {
 264       if (SRCPROPSP (p))
 265         SETSRCPROPALIST (p, scm_acons (key, datum, SRCPROPALIST (p)));
 266       else
 267         SCM_WHASHSET (scm_source_whash, h, scm_acons (key, datum, p));
 268     }
 269   return SCM_UNSPECIFIED;
 270 }
 271 #undef FUNC_NAME
 272
 273
 274 SCM_DEFINE (scm_cons_source, "cons-source", 3, 0, 0,
 275             (SCM xorig, SCM x, SCM y),
 276             "Create and return a new pair whose car and cdr are @var{x} and @var{y}.\n"
 277             "Any source properties associated with @var{xorig} are also associated\n"
 278             "with the new pair.")
 279 #define FUNC_NAME s_scm_cons_source
 280 {
 281   SCM p, z;
 282   z = scm_cons (x, y);
 283   /* Copy source properties possibly associated with xorig. */
 284   p = scm_whash_lookup (scm_source_whash, xorig);
 285   if (scm_is_true (p))
 286     scm_whash_insert (scm_source_whash, z, p);
 287   return z;
 288 }
 289 #undef FUNC_NAME
 290
 291
 292 void
 293 scm_init_srcprop ()
 294 {
 295   scm_tc16_srcprops = scm_make_smob_type ("srcprops", 0);
 296   scm_set_smob_print (scm_tc16_srcprops, srcprops_print);
 297
 298   scm_source_whash = scm_make_weak_key_hash_table (scm_from_int (2047));
 299   scm_c_define ("source-whash", scm_source_whash);
 300
 301   scm_last_alist_filename = scm_cons (SCM_EOL,
 302                                       scm_acons (SCM_EOL, SCM_EOL, SCM_EOL));
 303
 304 #include "libguile/srcprop.x"
 305 }
 306
 307
 308 /*
 309   Local Variables:
 310   c-file-style: "gnu"
 311   End:
 312 */