libguile/srcprop.c

   1 /* Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2006,
   2  *   2008, 2009, 2010, 2011, 2012 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 <errno.h>
  27
  28 #include "libguile/_scm.h"
  29 #include "libguile/async.h"
  30 #include "libguile/smob.h"
  31 #include "libguile/alist.h"
  32 #include "libguile/debug.h"
  33 #include "libguile/hashtab.h"
  34 #include "libguile/hash.h"
  35 #include "libguile/ports.h"
  36 #include "libguile/root.h"
  37 #include "libguile/gc.h"
  38
  39 #include "libguile/validate.h"
  40 #include "libguile/srcprop.h"
  41 #include "libguile/private-options.h"
  42
  43 \f
  44 /* {Source Properties}
  45  *
  46  * Properties of source list expressions.
  47  * Four of these have special meaning:
  48  *
  49  * filename    string   The name of the source file.
  50  * copy        list     A copy of the list expression.
  51  * line        integer  The source code line number.
  52  * column      integer  The source code column number.
  53  *
  54  * Most properties above can be set by the reader.
  55  *
  56  */
  57
  58 SCM_GLOBAL_SYMBOL (scm_sym_filename, "filename");
  59 SCM_GLOBAL_SYMBOL (scm_sym_copy, "copy");
  60 SCM_GLOBAL_SYMBOL (scm_sym_line, "line");
  61 SCM_GLOBAL_SYMBOL (scm_sym_column, "column");
  62
  63 static SCM scm_source_whash;
  64
  65
  66 /*
  67  *  Source properties are stored as double cells with the
  68  *  following layout:
  69
  70  * car = tag
  71  * cbr = pos
  72  * ccr = copy
  73  * cdr = alist
  74  */
  75
  76 #define SRCPROPSP(p) (SCM_SMOB_PREDICATE (scm_tc16_srcprops, (p)))
  77 #define SRCPROPPOS(p) (SCM_SMOB_DATA(p))
  78 #define SRCPROPLINE(p) (SRCPROPPOS(p) >> 12)
  79 #define SRCPROPCOL(p) (SRCPROPPOS(p) & 0x0fffL)
  80 #define SRCPROPCOPY(p) (SCM_SMOB_OBJECT_2(p))
  81 #define SRCPROPALIST(p) (SCM_SMOB_OBJECT_3(p))
  82 #define SRCPROPMAKPOS(l, c) (((l) << 12) + (c))
  83 #define SETSRCPROPPOS(p, l, c) (SCM_SET_SMOB_DATA_1 (p, SRCPROPMAKPOS (l, c)))
  84 #define SETSRCPROPLINE(p, l) SETSRCPROPPOS (p, l, SRCPROPCOL (p))
  85 #define SETSRCPROPCOL(p, c) SETSRCPROPPOS (p, SRCPROPLINE (p), c)
  86 #define SETSRCPROPCOPY(p, c) (SCM_SET_SMOB_OBJECT_2 (p, c))
  87 #define SETSRCPROPALIST(p, l) (SCM_SET_SMOB_OBJECT_3 (p, l))
  88
  89
  90 static SCM scm_srcprops_to_alist (SCM obj);
  91
  92
  93 scm_t_bits scm_tc16_srcprops;
  94
  95
  96 static int
  97 supports_source_props (SCM obj)
  98 {
  99   return SCM_NIMP (obj) && !scm_is_symbol (obj) && !scm_is_keyword (obj);
 100 }
 101
 102
 103 static int
 104 srcprops_print (SCM obj, SCM port, scm_print_state *pstate)
 105 {
 106   int writingp = SCM_WRITINGP (pstate);
 107   scm_puts_unlocked ("#<srcprops ", port);
 108   SCM_SET_WRITINGP (pstate, 1);
 109   scm_iprin1 (scm_srcprops_to_alist (obj), port, pstate);
 110   SCM_SET_WRITINGP (pstate, writingp);
 111   scm_putc_unlocked ('>', port);
 112   return 1;
 113 }
 114
 115
 116 /*
 117  * We remember the last file name settings, so we can share that alist
 118  * entry.  This works because scm_set_source_property_x does not use
 119  * assoc-set! for modifying the alist.
 120  *
 121  * This variable contains a protected cons, whose cdr is the cached
 122  * alist
 123  */
 124 static SCM scm_last_alist_filename;
 125
 126 SCM
 127 scm_make_srcprops (long line, int col, SCM filename, SCM copy, SCM alist)
 128 {
 129   if (!SCM_UNBNDP (filename))
 130     {
 131       SCM old_alist = alist;
 132
 133       /*
 134         have to extract the acons, and operate on that, for
 135         thread safety.
 136        */
 137       SCM last_acons = SCM_CDR (scm_last_alist_filename);
 138       if (scm_is_null (old_alist)
 139           && scm_is_eq (SCM_CDAR (last_acons), filename))
 140         {
 141           alist = last_acons;
 142         }
 143       else
 144         {
 145           alist = scm_acons (scm_sym_filename, filename, alist);
 146           if (scm_is_null (old_alist))
 147             SCM_SETCDR (scm_last_alist_filename, alist);
 148         }
 149     }
 150
 151   SCM_RETURN_NEWSMOB3 (scm_tc16_srcprops,
 152                        SRCPROPMAKPOS (line, col),
 153                        SCM_UNPACK (copy),
 154                        SCM_UNPACK (alist));
 155 }
 156
 157
 158 static SCM
 159 scm_srcprops_to_alist (SCM obj)
 160 {
 161   SCM alist = SRCPROPALIST (obj);
 162   if (!SCM_UNBNDP (SRCPROPCOPY (obj)))
 163     alist = scm_acons (scm_sym_copy, SRCPROPCOPY (obj), alist);
 164   alist = scm_acons (scm_sym_column, scm_from_int (SRCPROPCOL (obj)), alist);
 165   alist = scm_acons (scm_sym_line, scm_from_int (SRCPROPLINE (obj)), alist);
 166   return alist;
 167 }
 168
 169 SCM_DEFINE (scm_supports_source_properties_p, "supports-source-properties?", 1, 0, 0,
 170             (SCM obj),
 171             "Return #t if @var{obj} supports adding source properties,\n"
 172             "otherwise return #f.")
 173 #define FUNC_NAME s_scm_supports_source_properties_p
 174 {
 175   return scm_from_bool (supports_source_props (obj));
 176 }
 177 #undef FUNC_NAME
 178
 179 SCM_DEFINE (scm_source_properties, "source-properties", 1, 0, 0,
 180             (SCM obj),
 181             "Return the source property association list of @var{obj}.")
 182 #define FUNC_NAME s_scm_source_properties
 183 {
 184   if (SCM_IMP (obj))
 185     return SCM_EOL;
 186   else
 187     {
 188       SCM p = scm_weak_table_refq (scm_source_whash, obj, SCM_EOL);
 189
 190       if (SRCPROPSP (p))
 191         return scm_srcprops_to_alist (p);
 192       else
 193         /* list from set-source-properties!, or SCM_EOL for not found */
 194         return p;
 195     }
 196 }
 197 #undef FUNC_NAME
 198
 199 /* Perhaps this procedure should look through an alist
 200    and try to make a srcprops-object...? */
 201 SCM_DEFINE (scm_set_source_properties_x, "set-source-properties!", 2, 0, 0,
 202             (SCM obj, SCM alist),
 203             "Install the association list @var{alist} as the source property\n"
 204             "list for @var{obj}.")
 205 #define FUNC_NAME s_scm_set_source_properties_x
 206 {
 207   SCM_VALIDATE_NIM (1, obj);
 208
 209   scm_weak_table_putq_x (scm_source_whash, obj, alist);
 210
 211   return alist;
 212 }
 213 #undef FUNC_NAME
 214
 215 int
 216 scm_i_has_source_properties (SCM obj)
 217 #define FUNC_NAME "%set-source-properties"
 218 {
 219   if (SCM_IMP (obj))
 220     return 0;
 221   else
 222     return scm_is_true (scm_weak_table_refq (scm_source_whash, obj, SCM_BOOL_F));
 223 }
 224 #undef FUNC_NAME
 225
 226
 227 void
 228 scm_i_set_source_properties_x (SCM obj, long line, int col, SCM fname)
 229 #define FUNC_NAME "%set-source-properties"
 230 {
 231   SCM_VALIDATE_NIM (1, obj);
 232
 233   scm_weak_table_putq_x (scm_source_whash, obj,
 234                          scm_make_srcprops (line, col, fname,
 235                                             SCM_COPY_SOURCE_P
 236                                             ? scm_copy_tree (obj)
 237                                             : SCM_UNDEFINED,
 238                                             SCM_EOL));
 239 }
 240 #undef FUNC_NAME
 241
 242 SCM_DEFINE (scm_source_property, "source-property", 2, 0, 0,
 243             (SCM obj, SCM key),
 244             "Return the source property specified by @var{key} from\n"
 245             "@var{obj}'s source property list.")
 246 #define FUNC_NAME s_scm_source_property
 247 {
 248   SCM p;
 249
 250   if (SCM_IMP (obj))
 251     return SCM_BOOL_F;
 252
 253   p = scm_weak_table_refq (scm_source_whash, obj, SCM_EOL);
 254
 255   if (!SRCPROPSP (p))
 256     goto alist;
 257   if (scm_is_eq (scm_sym_line, key))
 258     return scm_from_int (SRCPROPLINE (p));
 259   else if (scm_is_eq (scm_sym_column, key))
 260     return scm_from_int (SRCPROPCOL (p));
 261   else if (scm_is_eq (scm_sym_copy, key))
 262     return SRCPROPCOPY (p);
 263   else
 264     {
 265       p = SRCPROPALIST (p);
 266     alist:
 267       p = scm_assoc (key, p);
 268       return (scm_is_pair (p) ? SCM_CDR (p) : SCM_BOOL_F);
 269     }
 270 }
 271 #undef FUNC_NAME
 272
 273 SCM_DEFINE (scm_set_source_property_x, "set-source-property!", 3, 0, 0,
 274             (SCM obj, SCM key, SCM datum),
 275             "Set the source property of object @var{obj}, which is specified by\n"
 276             "@var{key} to @var{datum}.  Normally, the key will be a symbol.")
 277 #define FUNC_NAME s_scm_set_source_property_x
 278 {
 279   SCM p;
 280   SCM_VALIDATE_NIM (1, obj);
 281
 282   scm_i_pthread_mutex_lock (&scm_i_misc_mutex);
 283   p = scm_weak_table_refq (scm_source_whash, obj, SCM_EOL);
 284
 285   if (scm_is_eq (scm_sym_line, key))
 286     {
 287       if (SRCPROPSP (p))
 288         SETSRCPROPLINE (p, scm_to_int (datum));
 289       else
 290         scm_weak_table_putq_x (scm_source_whash, obj,
 291                                scm_make_srcprops (scm_to_int (datum), 0,
 292                                                   SCM_UNDEFINED, SCM_UNDEFINED, p));
 293     }
 294   else if (scm_is_eq (scm_sym_column, key))
 295     {
 296       if (SRCPROPSP (p))
 297         SETSRCPROPCOL (p, scm_to_int (datum));
 298       else
 299         scm_weak_table_putq_x (scm_source_whash, obj,
 300                                scm_make_srcprops (0, scm_to_int (datum),
 301                                                   SCM_UNDEFINED, SCM_UNDEFINED, p));
 302     }
 303   else if (scm_is_eq (scm_sym_copy, key))
 304     {
 305       if (SRCPROPSP (p))
 306         SETSRCPROPCOPY (p, datum);
 307       else
 308         scm_weak_table_putq_x (scm_source_whash, obj,
 309                                scm_make_srcprops (0, 0, SCM_UNDEFINED, datum, p));
 310     }
 311   else
 312     {
 313       if (SRCPROPSP (p))
 314         SETSRCPROPALIST (p, scm_acons (key, datum, SRCPROPALIST (p)));
 315       else
 316         scm_weak_table_putq_x (scm_source_whash, obj,
 317                                scm_acons (key, datum, p));
 318     }
 319   scm_i_pthread_mutex_unlock (&scm_i_misc_mutex);
 320
 321   return SCM_UNSPECIFIED;
 322 }
 323 #undef FUNC_NAME
 324
 325
 326 SCM_DEFINE (scm_cons_source, "cons-source", 3, 0, 0,
 327             (SCM xorig, SCM x, SCM y),
 328             "Create and return a new pair whose car and cdr are @var{x} and @var{y}.\n"
 329             "Any source properties associated with @var{xorig} are also associated\n"
 330             "with the new pair.")
 331 #define FUNC_NAME s_scm_cons_source
 332 {
 333   SCM p, z;
 334   z = scm_cons (x, y);
 335   /* Copy source properties possibly associated with xorig. */
 336   p = scm_weak_table_refq (scm_source_whash, xorig, SCM_BOOL_F);
 337   if (scm_is_true (p))
 338     scm_weak_table_putq_x (scm_source_whash, z, p);
 339   return z;
 340 }
 341 #undef FUNC_NAME
 342
 343
 344 void
 345 scm_init_srcprop ()
 346 {
 347   scm_tc16_srcprops = scm_make_smob_type ("srcprops", 0);
 348   scm_set_smob_print (scm_tc16_srcprops, srcprops_print);
 349
 350   scm_source_whash = scm_c_make_weak_table (0, SCM_WEAK_TABLE_KIND_KEY);
 351   scm_c_define ("source-whash", scm_source_whash);
 352
 353   scm_last_alist_filename = scm_cons (SCM_EOL,
 354                                       scm_acons (SCM_EOL, SCM_EOL, SCM_EOL));
 355
 356 #include "libguile/srcprop.x"
 357 }
 358
 359
 360 /*
 361   Local Variables:
 362   c-file-style: "gnu"
 363   End:
 364 */