src/category.c

   1 /* GNU Emacs routines to deal with category tables.
   2    Copyright (C) 1998, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
   3      Free Software Foundation, Inc.
   4    Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
   5      2005, 2006, 2007, 2008, 2009
   6      National Institute of Advanced Industrial Science and Technology (AIST)
   7      Registration Number H14PRO021
   8    Copyright (C) 2003
   9      National Institute of Advanced Industrial Science and Technology (AIST)
  10      Registration Number H13PRO009
  11
  12 This file is part of GNU Emacs.
  13
  14 GNU Emacs is free software: you can redistribute it and/or modify
  15 it under the terms of the GNU General Public License as published by
  16 the Free Software Foundation, either version 3 of the License, or
  17 (at your option) any later version.
  18
  19 GNU Emacs is distributed in the hope that it will be useful,
  20 but WITHOUT ANY WARRANTY; without even the implied warranty of
  21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22 GNU General Public License for more details.
  23
  24 You should have received a copy of the GNU General Public License
  25 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  26
  27
  28 /* Here we handle three objects: category, category set, and category
  29    table.  Read comments in the file category.h to understand them.  */
  30
  31 #include <config.h>
  32 #include <ctype.h>
  33 #include <setjmp.h>
  34 #include "lisp.h"
  35 #include "buffer.h"
  36 #include "character.h"
  37 #include "charset.h"
  38 #include "category.h"
  39 #include "keymap.h"
  40
  41 /* The version number of the latest category table.  Each category
  42    table has a unique version number.  It is assigned a new number
  43    also when it is modified.  When a regular expression is compiled
  44    into the struct re_pattern_buffer, the version number of the
  45    category table (of the current buffer) at that moment is also
  46    embedded in the structure.
  47
  48    For the moment, we are not using this feature.  */
  49 static int category_table_version;
  50
  51 Lisp_Object Qcategory_table, Qcategoryp, Qcategorysetp, Qcategory_table_p;
  52
  53 /* Variables to determine word boundary.  */
  54 Lisp_Object Vword_combining_categories, Vword_separating_categories;
  55
  56 /* Temporary internal variable used in macro CHAR_HAS_CATEGORY.  */
  57 Lisp_Object _temp_category_set;
  58
  59 \f
  60 /* Category set staff.  */
  61
  62 static Lisp_Object hash_get_category_set P_ ((Lisp_Object, Lisp_Object));
  63
  64 static Lisp_Object
  65 hash_get_category_set (table, category_set)
  66      Lisp_Object table, category_set;
  67 {
  68   Lisp_Object val;
  69   struct Lisp_Hash_Table *h;
  70   int i;
  71   unsigned hash;
  72
  73   if (NILP (XCHAR_TABLE (table)->extras[1]))
  74     XCHAR_TABLE (table)->extras[1]
  75       = make_hash_table (Qequal, make_number (DEFAULT_HASH_SIZE),
  76                          make_float (DEFAULT_REHASH_SIZE),
  77                          make_float (DEFAULT_REHASH_THRESHOLD),
  78                          Qnil, Qnil, Qnil);
  79   h = XHASH_TABLE (XCHAR_TABLE (table)->extras[1]);
  80   i = hash_lookup (h, category_set, &hash);
  81   if (i >= 0)
  82     return HASH_KEY (h, i);
  83   hash_put (h, category_set, Qnil, hash);
  84   return category_set;
  85 }
  86
  87
  88 DEFUN ("make-category-set", Fmake_category_set, Smake_category_set, 1, 1, 0,
  89        doc: /* Return a newly created category-set which contains CATEGORIES.
  90 CATEGORIES is a string of category mnemonics.
  91 The value is a bool-vector which has t at the indices corresponding to
  92 those categories.  */)
  93      (categories)
  94      Lisp_Object categories;
  95 {
  96   Lisp_Object val;
  97   int len;
  98
  99   CHECK_STRING (categories);
 100   val = MAKE_CATEGORY_SET;
 101
 102   if (STRING_MULTIBYTE (categories))
 103     error ("Multibyte string in `make-category-set'");
 104
 105   len = SCHARS (categories);
 106   while (--len >= 0)
 107     {
 108       Lisp_Object category;
 109
 110       XSETFASTINT (category, SREF (categories, len));
 111       CHECK_CATEGORY (category);
 112       SET_CATEGORY_SET (val, category, Qt);
 113     }
 114   return val;
 115 }
 116
 117 \f
 118 /* Category staff.  */
 119
 120 Lisp_Object check_category_table ();
 121
 122 DEFUN ("define-category", Fdefine_category, Sdefine_category, 2, 3, 0,
 123        doc: /* Define CATEGORY as a category which is described by DOCSTRING.
 124 CATEGORY should be an ASCII printing character in the range ` ' to `~'.
 125 DOCSTRING is the documentation string of the category.  The first line
 126 should be a terse text (preferably less than 16 characters),
 127 and the rest lines should be the full description.
 128 The category is defined only in category table TABLE, which defaults to
 129 the current buffer's category table.  */)
 130      (category, docstring, table)
 131      Lisp_Object category, docstring, table;
 132 {
 133   CHECK_CATEGORY (category);
 134   CHECK_STRING (docstring);
 135   table = check_category_table (table);
 136
 137   if (!NILP (CATEGORY_DOCSTRING (table, XFASTINT (category))))
 138     error ("Category `%c' is already defined", XFASTINT (category));
 139   if (!NILP (Vpurify_flag))
 140     docstring = Fpurecopy (docstring);
 141   CATEGORY_DOCSTRING (table, XFASTINT (category)) = docstring;
 142
 143   return Qnil;
 144 }
 145
 146 DEFUN ("category-docstring", Fcategory_docstring, Scategory_docstring, 1, 2, 0,
 147        doc: /* Return the documentation string of CATEGORY, as defined in TABLE.
 148 TABLE should be a category table and defaults to the current buffer's
 149 category table.  */)
 150      (category, table)
 151      Lisp_Object category, table;
 152 {
 153   CHECK_CATEGORY (category);
 154   table = check_category_table (table);
 155
 156   return CATEGORY_DOCSTRING (table, XFASTINT (category));
 157 }
 158
 159 DEFUN ("get-unused-category", Fget_unused_category, Sget_unused_category,
 160        0, 1, 0,
 161        doc: /* Return a category which is not yet defined in TABLE.
 162 If no category remains available, return nil.
 163 The optional argument TABLE specifies which category table to modify;
 164 it defaults to the current buffer's category table.  */)
 165      (table)
 166      Lisp_Object table;
 167 {
 168   int i;
 169
 170   table = check_category_table (table);
 171
 172   for (i = ' '; i <= '~'; i++)
 173     if (NILP (CATEGORY_DOCSTRING (table, i)))
 174       return make_number (i);
 175
 176   return Qnil;
 177 }
 178
 179 \f
 180 /* Category-table staff.  */
 181
 182 DEFUN ("category-table-p", Fcategory_table_p, Scategory_table_p, 1, 1, 0,
 183        doc: /* Return t if ARG is a category table.  */)
 184      (arg)
 185      Lisp_Object arg;
 186 {
 187   if (CHAR_TABLE_P (arg)
 188       && EQ (XCHAR_TABLE (arg)->purpose, Qcategory_table))
 189     return Qt;
 190   return Qnil;
 191 }
 192
 193 /* If TABLE is nil, return the current category table.  If TABLE is
 194    not nil, check the validity of TABLE as a category table.  If
 195    valid, return TABLE itself, but if not valid, signal an error of
 196    wrong-type-argument.  */
 197
 198 Lisp_Object
 199 check_category_table (table)
 200      Lisp_Object table;
 201 {
 202   if (NILP (table))
 203     return current_buffer->category_table;
 204   CHECK_TYPE (!NILP (Fcategory_table_p (table)), Qcategory_table_p, table);
 205   return table;
 206 }
 207
 208 DEFUN ("category-table", Fcategory_table, Scategory_table, 0, 0, 0,
 209        doc: /* Return the current category table.
 210 This is the one specified by the current buffer.  */)
 211      ()
 212 {
 213   return current_buffer->category_table;
 214 }
 215
 216 DEFUN ("standard-category-table", Fstandard_category_table,
 217    Sstandard_category_table, 0, 0, 0,
 218        doc: /* Return the standard category table.
 219 This is the one used for new buffers.  */)
 220      ()
 221 {
 222   return Vstandard_category_table;
 223 }
 224
 225
 226 static void
 227 copy_category_entry (table, c, val)
 228      Lisp_Object table, c, val;
 229 {
 230   val = Fcopy_sequence (val);
 231   if (CONSP (c))
 232     char_table_set_range (table, XINT (XCAR (c)), XINT (XCDR (c)), val);
 233   else
 234     char_table_set (table, XINT (c), val);
 235 }
 236
 237 /* Return a copy of category table TABLE.  We can't simply use the
 238    function copy-sequence because no contents should be shared between
 239    the original and the copy.  This function is called recursively by
 240    binding TABLE to a sub char table.  */
 241
 242 Lisp_Object
 243 copy_category_table (table)
 244      Lisp_Object table;
 245 {
 246   table = copy_char_table (table);
 247
 248   if (! NILP (XCHAR_TABLE (table)->defalt))
 249     XCHAR_TABLE (table)->defalt
 250       = Fcopy_sequence (XCHAR_TABLE (table)->defalt);
 251   XCHAR_TABLE (table)->extras[0]
 252     = Fcopy_sequence (XCHAR_TABLE (table)->extras[0]);
 253   map_char_table (copy_category_entry, Qnil, table, table);
 254
 255   return table;
 256 }
 257
 258 DEFUN ("copy-category-table", Fcopy_category_table, Scopy_category_table,
 259        0, 1, 0,
 260        doc: /* Construct a new category table and return it.
 261 It is a copy of the TABLE, which defaults to the standard category table.  */)
 262      (table)
 263      Lisp_Object table;
 264 {
 265   if (!NILP (table))
 266     check_category_table (table);
 267   else
 268     table = Vstandard_category_table;
 269
 270   return copy_category_table (table);
 271 }
 272
 273 DEFUN ("make-category-table", Fmake_category_table, Smake_category_table,
 274        0, 0, 0,
 275        doc: /* Construct a new and empty category table and return it.  */)
 276      ()
 277 {
 278   Lisp_Object val;
 279   int i;
 280
 281   val = Fmake_char_table (Qcategory_table, Qnil);
 282   XCHAR_TABLE (val)->defalt = MAKE_CATEGORY_SET;
 283   for (i = 0; i < (1 << CHARTAB_SIZE_BITS_0); i++)
 284     XCHAR_TABLE (val)->contents[i] = MAKE_CATEGORY_SET;
 285   Fset_char_table_extra_slot (val, make_number (0),
 286                               Fmake_vector (make_number (95), Qnil));
 287   return val;
 288 }
 289
 290 DEFUN ("set-category-table", Fset_category_table, Sset_category_table, 1, 1, 0,
 291        doc: /* Specify TABLE as the category table for the current buffer.
 292 Return TABLE.  */)
 293      (table)
 294      Lisp_Object table;
 295 {
 296   int idx;
 297   table = check_category_table (table);
 298   current_buffer->category_table = table;
 299   /* Indicate that this buffer now has a specified category table.  */
 300   idx = PER_BUFFER_VAR_IDX (category_table);
 301   SET_PER_BUFFER_VALUE_P (current_buffer, idx, 1);
 302   return table;
 303 }
 304
 305 \f
 306 Lisp_Object
 307 char_category_set (c)
 308      int c;
 309 {
 310   return CHAR_TABLE_REF (current_buffer->category_table, c);
 311 }
 312
 313 DEFUN ("char-category-set", Fchar_category_set, Schar_category_set, 1, 1, 0,
 314        doc: /* Return the category set of CHAR.
 315 usage: (char-category-set CHAR)  */)
 316      (ch)
 317      Lisp_Object ch;
 318 {
 319   CHECK_NUMBER (ch);
 320   return CATEGORY_SET (XFASTINT (ch));
 321 }
 322
 323 DEFUN ("category-set-mnemonics", Fcategory_set_mnemonics,
 324        Scategory_set_mnemonics, 1, 1, 0,
 325        doc: /* Return a string containing mnemonics of the categories in CATEGORY-SET.
 326 CATEGORY-SET is a bool-vector, and the categories \"in\" it are those
 327 that are indexes where t occurs in the bool-vector.
 328 The return value is a string containing those same categories.  */)
 329      (category_set)
 330      Lisp_Object category_set;
 331 {
 332   int i, j;
 333   char str[96];
 334
 335   CHECK_CATEGORY_SET (category_set);
 336
 337   j = 0;
 338   for (i = 32; i < 127; i++)
 339     if (CATEGORY_MEMBER (i, category_set))
 340       str[j++] = i;
 341   str[j] = '\0';
 342
 343   return build_string (str);
 344 }
 345
 346 void
 347 set_category_set (category_set, category, val)
 348      Lisp_Object category_set, category, val;
 349 {
 350   do {
 351     int idx = XINT (category) / 8;
 352     unsigned char bits = 1 << (XINT (category) % 8);
 353
 354     if (NILP (val))
 355       XCATEGORY_SET (category_set)->data[idx] &= ~bits;
 356     else
 357       XCATEGORY_SET (category_set)->data[idx] |= bits;
 358   } while (0);
 359 }
 360
 361 DEFUN ("modify-category-entry", Fmodify_category_entry,
 362        Smodify_category_entry, 2, 4, 0,
 363        doc: /* Modify the category set of CHARACTER by adding CATEGORY to it.
 364 The category is changed only for table TABLE, which defaults to
 365 the current buffer's category table.
 366 CHARACTER can be either a single character or a cons representing the
 367 lower and upper ends of an inclusive character range to modify.
 368 If optional fourth argument RESET is non-nil,
 369 then delete CATEGORY from the category set instead of adding it.  */)
 370      (character, category, table, reset)
 371      Lisp_Object character, category, table, reset;
 372 {
 373   Lisp_Object set_value;        /* Actual value to be set in category sets.  */
 374   Lisp_Object category_set;
 375   int start, end;
 376   int from, to;
 377
 378   if (INTEGERP (character))
 379     {
 380       CHECK_CHARACTER (character);
 381       start = end = XFASTINT (character);
 382     }
 383   else
 384     {
 385       CHECK_CONS (character);
 386       CHECK_CHARACTER_CAR (character);
 387       CHECK_CHARACTER_CDR (character);
 388       start = XFASTINT (XCAR (character));
 389       end = XFASTINT (XCDR (character));
 390     }
 391
 392   CHECK_CATEGORY (category);
 393   table = check_category_table (table);
 394
 395   if (NILP (CATEGORY_DOCSTRING (table, XFASTINT (category))))
 396     error ("Undefined category: %c", XFASTINT (category));
 397
 398   set_value = NILP (reset) ? Qt : Qnil;
 399
 400   while (start <= end)
 401     {
 402       from = start, to = end;
 403       category_set = char_table_ref_and_range (table, start, &from, &to);
 404       if (CATEGORY_MEMBER (XFASTINT (category), category_set) != NILP (reset))
 405         {
 406           category_set = Fcopy_sequence (category_set);
 407           SET_CATEGORY_SET (category_set, category, set_value);
 408           category_set = hash_get_category_set (table, category_set);
 409           char_table_set_range (table, start, to, category_set);
 410         }
 411       start = to + 1;
 412     }
 413
 414   return Qnil;
 415 }
 416 \f
 417 /* Return 1 if there is a word boundary between two word-constituent
 418    characters C1 and C2 if they appear in this order, else return 0.
 419    Use the macro WORD_BOUNDARY_P instead of calling this function
 420    directly.  */
 421
 422 int
 423 word_boundary_p (c1, c2)
 424      int c1, c2;
 425 {
 426   Lisp_Object category_set1, category_set2;
 427   Lisp_Object tail;
 428   int default_result;
 429
 430   if (EQ (CHAR_TABLE_REF (Vchar_script_table, c1),
 431           CHAR_TABLE_REF (Vchar_script_table, c2)))
 432     {
 433       tail = Vword_separating_categories;
 434       default_result = 0;
 435     }
 436   else
 437     {
 438       tail = Vword_combining_categories;
 439       default_result = 1;
 440     }
 441
 442   category_set1 = CATEGORY_SET (c1);
 443   if (NILP (category_set1))
 444     return default_result;
 445   category_set2 = CATEGORY_SET (c2);
 446   if (NILP (category_set2))
 447     return default_result;
 448
 449   for (; CONSP (tail); tail = XCDR (tail))
 450     {
 451       Lisp_Object elt = XCAR (tail);
 452
 453       if (CONSP (elt)
 454           && (NILP (XCAR (elt))
 455               || (CATEGORYP (XCAR (elt))
 456                   && CATEGORY_MEMBER (XFASTINT (XCAR (elt)), category_set1)))
 457           && (NILP (XCDR (elt))
 458               || (CATEGORYP (XCDR (elt))
 459                   && CATEGORY_MEMBER (XFASTINT (XCDR (elt)), category_set2))))
 460         return !default_result;
 461     }
 462   return default_result;
 463 }
 464
 465 \f
 466 void
 467 init_category_once ()
 468 {
 469   /* This has to be done here, before we call Fmake_char_table.  */
 470   Qcategory_table = intern ("category-table");
 471   staticpro (&Qcategory_table);
 472
 473   /* Intern this now in case it isn't already done.
 474      Setting this variable twice is harmless.
 475      But don't staticpro it here--that is done in alloc.c.  */
 476   Qchar_table_extra_slots = intern ("char-table-extra-slots");
 477
 478   /* Now we are ready to set up this property, so we can
 479      create category tables.  */
 480   Fput (Qcategory_table, Qchar_table_extra_slots, make_number (2));
 481
 482   Vstandard_category_table = Fmake_char_table (Qcategory_table, Qnil);
 483   /* Set a category set which contains nothing to the default.  */
 484   XCHAR_TABLE (Vstandard_category_table)->defalt = MAKE_CATEGORY_SET;
 485   Fset_char_table_extra_slot (Vstandard_category_table, make_number (0),
 486                               Fmake_vector (make_number (95), Qnil));
 487 }
 488
 489 void
 490 syms_of_category ()
 491 {
 492   Qcategoryp = intern ("categoryp");
 493   staticpro (&Qcategoryp);
 494   Qcategorysetp = intern ("categorysetp");
 495   staticpro (&Qcategorysetp);
 496   Qcategory_table_p = intern ("category-table-p");
 497   staticpro (&Qcategory_table_p);
 498
 499   DEFVAR_LISP ("word-combining-categories", &Vword_combining_categories,
 500                doc: /* List of pair (cons) of categories to determine word boundary.
 501
 502 Emacs treats a sequence of word constituent characters as a single
 503 word (i.e. finds no word boundary between them) only if they belong to
 504 the same script.  But, exceptions are allowed in the following cases.
 505
 506 \(1) The case that characters are in different scripts is controlled
 507 by the variable `word-combining-categories'.
 508
 509 Emacs finds no word boundary between characters of different scripts
 510 if they have categories matching some element of this list.
 511
 512 More precisely, if an element of this list is a cons of category CAT1
 513 and CAT2, and a multibyte character C1 which has CAT1 is followed by
 514 C2 which has CAT2, there's no word boundary between C1 and C2.
 515
 516 For instance, to tell that Han characters followed by Hiragana
 517 characters can form a single word, the element `(?C . ?H)' should be
 518 in this list.
 519
 520 \(2) The case that character are in the same script is controlled by
 521 the variable `word-separating-categories'.
 522
 523 Emacs finds a word boundary between characters of the same script
 524 if they have categories matching some element of this list.
 525
 526 More precisely, if an element of this list is a cons of category CAT1
 527 and CAT2, and a multibyte character C1 which has CAT1 is followed by
 528 C2 which has CAT2, there's a word boundary between C1 and C2.
 529
 530 For instance, to tell that there's a word boundary between Hiragana
 531 and Katakana (both are in the same script `kana'),
 532 the element `(?H . ?K) should be in this list.  */);
 533
 534   Vword_combining_categories = Qnil;
 535
 536   DEFVAR_LISP ("word-separating-categories", &Vword_separating_categories,
 537                doc: /* List of pair (cons) of categories to determine word boundary.
 538 See the documentation of the variable `word-combining-categories'.  */);
 539
 540   Vword_separating_categories = Qnil;
 541
 542   defsubr (&Smake_category_set);
 543   defsubr (&Sdefine_category);
 544   defsubr (&Scategory_docstring);
 545   defsubr (&Sget_unused_category);
 546   defsubr (&Scategory_table_p);
 547   defsubr (&Scategory_table);
 548   defsubr (&Sstandard_category_table);
 549   defsubr (&Scopy_category_table);
 550   defsubr (&Smake_category_table);
 551   defsubr (&Sset_category_table);
 552   defsubr (&Schar_category_set);
 553   defsubr (&Scategory_set_mnemonics);
 554   defsubr (&Smodify_category_entry);
 555
 556   category_table_version = 0;
 557 }
 558
 559 /* arch-tag: 74ebf524-121b-4d9c-bd68-07f8d708b211
 560    (do not change this comment) */