src/category.c

   1 /* GNU Emacs routines to deal with category tables.
   2    Copyright (C) 1995, 1997 Electrotechnical Laboratory, JAPAN.
   3    Licensed to the Free Software Foundation.
   4    Copyright (C) 2001, 2002
   5      National Institute of Advanced Industrial Science and Technology (AIST)
   6      Registration Number H13PRO009
   7
   8 This file is part of GNU Emacs.
   9
  10 GNU Emacs is free software; you can redistribute it and/or modify
  11 it under the terms of the GNU General Public License as published by
  12 the Free Software Foundation; either version 2, or (at your option)
  13 any later version.
  14
  15 GNU Emacs is distributed in the hope that it will be useful,
  16 but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 GNU General Public License for more details.
  19
  20 You should have received a copy of the GNU General Public License
  21 along with GNU Emacs; see the file COPYING.  If not, write to
  22 the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  23 Boston, MA 02111-1307, USA.  */
  24
  25
  26 /* Here we handle three objects: category, category set, and category
  27    table.  Read comments in the file category.h to understand them.  */
  28
  29 #include <config.h>
  30 #include <ctype.h>
  31 #include "lisp.h"
  32 #include "buffer.h"
  33 #include "character.h"
  34 #include "charset.h"
  35 #include "category.h"
  36 #include "keymap.h"
  37
  38 /* The version number of the latest category table.  Each category
  39    table has a unique version number.  It is assigned a new number
  40    also when it is modified.  When a regular expression is compiled
  41    into the struct re_pattern_buffer, the version number of the
  42    category table (of the current buffer) at that moment is also
  43    embedded in the structure.
  44
  45    For the moment, we are not using this feature.  */
  46 static int category_table_version;
  47
  48 Lisp_Object Qcategory_table, Qcategoryp, Qcategorysetp, Qcategory_table_p;
  49
  50 /* Variables to determine word boundary.  */
  51 Lisp_Object Vword_combining_categories, Vword_separating_categories;
  52
  53 /* Temporary internal variable used in macro CHAR_HAS_CATEGORY.  */
  54 Lisp_Object _temp_category_set;
  55
  56 \f
  57 /* Category set staff.  */
  58
  59 DEFUN ("make-category-set", Fmake_category_set, Smake_category_set, 1, 1, 0,
  60        doc: /* Return a newly created category-set which contains CATEGORIES.
  61 CATEGORIES is a string of category mnemonics.
  62 The value is a bool-vector which has t at the indices corresponding to
  63 those categories.  */)
  64      (categories)
  65      Lisp_Object categories;
  66 {
  67   Lisp_Object val;
  68   int len;
  69
  70   CHECK_STRING (categories);
  71   val = MAKE_CATEGORY_SET;
  72
  73   if (STRING_MULTIBYTE (categories))
  74     error ("Multibyte string in make-category-set");
  75
  76   len = XSTRING (categories)->size;
  77   while (--len >= 0)
  78     {
  79       Lisp_Object category;
  80
  81       XSETFASTINT (category, XSTRING (categories)->data[len]);
  82       CHECK_CATEGORY (category);
  83       SET_CATEGORY_SET (val, category, Qt);
  84     }
  85   return val;
  86 }
  87
  88 \f
  89 /* Category staff.  */
  90
  91 Lisp_Object check_category_table ();
  92
  93 DEFUN ("define-category", Fdefine_category, Sdefine_category, 2, 3, 0,
  94        doc: /* Define CHAR as a category which is described by DOCSTRING.
  95 CHAR should be an ASCII printing character in the range ` ' to `~'.
  96 DOCSTRING is a documentation string of the category.
  97 The category is defined only in category table TABLE, which defaults to
  98  the current buffer's category table.  */)
  99      (category, docstring, table)
 100      Lisp_Object category, docstring, table;
 101 {
 102   CHECK_CATEGORY (category);
 103   CHECK_STRING (docstring);
 104   table = check_category_table (table);
 105
 106   if (!NILP (CATEGORY_DOCSTRING (table, XFASTINT (category))))
 107     error ("Category `%c' is already defined", XFASTINT (category));
 108   CATEGORY_DOCSTRING (table, XFASTINT (category)) = docstring;
 109
 110   return Qnil;
 111 }
 112
 113 DEFUN ("category-docstring", Fcategory_docstring, Scategory_docstring, 1, 2, 0,
 114        doc: /* Return the documentation string of CATEGORY, as defined in CATEGORY-TABLE.  */)
 115      (category, table)
 116      Lisp_Object category, table;
 117 {
 118   CHECK_CATEGORY (category);
 119   table = check_category_table (table);
 120
 121   return CATEGORY_DOCSTRING (table, XFASTINT (category));
 122 }
 123
 124 DEFUN ("get-unused-category", Fget_unused_category, Sget_unused_category,
 125        0, 1, 0,
 126        doc: /* Return a category which is not yet defined in CATEGORY-TABLE.
 127 If no category remains available, return nil.
 128 The optional argument CATEGORY-TABLE
 129 specifies which category table to modify;
 130 it defaults to the current buffer's category table.  */)
 131      (table)
 132      Lisp_Object table;
 133 {
 134   int i;
 135
 136   table = check_category_table (table);
 137
 138   for (i = ' '; i <= '~'; i++)
 139     if (NILP (CATEGORY_DOCSTRING (table, i)))
 140       return make_number (i);
 141
 142   return Qnil;
 143 }
 144
 145 \f
 146 /* Category-table staff.  */
 147
 148 DEFUN ("category-table-p", Fcategory_table_p, Scategory_table_p, 1, 1, 0,
 149        doc: /* Return t if ARG is a category table.  */)
 150      (arg)
 151      Lisp_Object arg;
 152 {
 153   if (CHAR_TABLE_P (arg)
 154       && EQ (XCHAR_TABLE (arg)->purpose, Qcategory_table))
 155     return Qt;
 156   return Qnil;
 157 }
 158
 159 /* If TABLE is nil, return the current category table.  If TABLE is
 160    not nil, check the validity of TABLE as a category table.  If
 161    valid, return TABLE itself, but if not valid, signal an error of
 162    wrong-type-argument.  */
 163
 164 Lisp_Object
 165 check_category_table (table)
 166      Lisp_Object table;
 167 {
 168   register Lisp_Object tem;
 169   if (NILP (table))
 170     return current_buffer->category_table;
 171   while (tem = Fcategory_table_p (table), NILP (tem))
 172     table = wrong_type_argument (Qcategory_table_p, table);
 173   return table;
 174 }
 175
 176 DEFUN ("category-table", Fcategory_table, Scategory_table, 0, 0, 0,
 177        doc: /* Return the current category table.
 178 This is the one specified by the current buffer.  */)
 179      ()
 180 {
 181   return current_buffer->category_table;
 182 }
 183
 184 DEFUN ("standard-category-table", Fstandard_category_table,
 185    Sstandard_category_table, 0, 0, 0,
 186        doc: /* Return the standard category table.
 187 This is the one used for new buffers.  */)
 188      ()
 189 {
 190   return Vstandard_category_table;
 191 }
 192
 193
 194 static void
 195 copy_category_entry (table, range, val)
 196      Lisp_Object table, range, val;
 197 {
 198   char_table_set_range (table, XINT (XCAR (range)), XINT (XCDR (range)),
 199                         Fcopy_sequence (val));
 200 }
 201
 202 /* Return a copy of category table TABLE.  We can't simply use the
 203    function copy-sequence because no contents should be shared between
 204    the original and the copy.  This function is called recursively by
 205    binding TABLE to a sub char table.  */
 206
 207 Lisp_Object
 208 copy_category_table (table)
 209      Lisp_Object table;
 210 {
 211   table = copy_char_table (table);
 212
 213   if (! NILP (XCHAR_TABLE (table)->defalt))
 214     XCHAR_TABLE (table)->defalt
 215       = Fcopy_sequence (XCHAR_TABLE (table)->defalt);
 216   XCHAR_TABLE (table)->extras[0]
 217     = Fcopy_sequence (XCHAR_TABLE (table)->extras[0]);
 218
 219   map_char_table (copy_category_entry, Qnil, table, table, 0, NULL);
 220
 221   return table;
 222 }
 223
 224 DEFUN ("copy-category-table", Fcopy_category_table, Scopy_category_table,
 225        0, 1, 0,
 226        doc: /* Construct a new category table and return it.
 227 It is a copy of the TABLE, which defaults to the standard category table.  */)
 228      (table)
 229      Lisp_Object table;
 230 {
 231   if (!NILP (table))
 232     check_category_table (table);
 233   else
 234     table = Vstandard_category_table;
 235
 236   return copy_category_table (table);
 237 }
 238
 239 DEFUN ("make-category-table", Fmake_category_table, Smake_category_table,
 240        0, 0, 0,
 241        doc: /* Construct a new and empty category table and return it.  */)
 242      ()
 243 {
 244   Lisp_Object val;
 245   int i;
 246
 247   val = Fmake_char_table (Qcategory_table, Qnil);
 248   XCHAR_TABLE (val)->defalt = MAKE_CATEGORY_SET;
 249   for (i = 0; i < (1 << CHARTAB_SIZE_BITS_0); i++)
 250     XCHAR_TABLE (val)->contents[i] = MAKE_CATEGORY_SET;
 251   Fset_char_table_extra_slot (val, make_number (0),
 252                               Fmake_vector (make_number (95), Qnil));
 253   return val;
 254 }
 255
 256 DEFUN ("set-category-table", Fset_category_table, Sset_category_table, 1, 1, 0,
 257        doc: /* Specify TABLE as the category table for the current buffer.  */)
 258      (table)
 259      Lisp_Object table;
 260 {
 261   int idx;
 262   table = check_category_table (table);
 263   current_buffer->category_table = table;
 264   /* Indicate that this buffer now has a specified category table.  */
 265   idx = PER_BUFFER_VAR_IDX (category_table);
 266   SET_PER_BUFFER_VALUE_P (current_buffer, idx, 1);
 267   return table;
 268 }
 269
 270 \f
 271 Lisp_Object
 272 char_category_set (c)
 273      int c;
 274 {
 275   return CHAR_TABLE_REF (current_buffer->category_table, c);
 276 }
 277
 278 DEFUN ("char-category-set", Fchar_category_set, Schar_category_set, 1, 1, 0,
 279        doc: /* Return the category set of CHAR.  */)
 280      (ch)
 281      Lisp_Object ch;
 282 {
 283   CHECK_NUMBER (ch);
 284   return CATEGORY_SET (XFASTINT (ch));
 285 }
 286
 287 DEFUN ("category-set-mnemonics", Fcategory_set_mnemonics,
 288        Scategory_set_mnemonics, 1, 1, 0,
 289        doc: /* Return a string containing mnemonics of the categories in CATEGORY-SET.
 290 CATEGORY-SET is a bool-vector, and the categories \"in\" it are those
 291 that are indexes where t occurs the bool-vector.
 292 The return value is a string containing those same categories.  */)
 293      (category_set)
 294      Lisp_Object category_set;
 295 {
 296   int i, j;
 297   char str[96];
 298
 299   CHECK_CATEGORY_SET (category_set);
 300
 301   j = 0;
 302   for (i = 32; i < 127; i++)
 303     if (CATEGORY_MEMBER (i, category_set))
 304       str[j++] = i;
 305   str[j] = '\0';
 306
 307   return build_string (str);
 308 }
 309
 310 void
 311 set_category_set (category_set, category, val)
 312      Lisp_Object category_set, category, val;
 313 {
 314   do {
 315     int idx = XINT (category) / 8;
 316     unsigned char bits = 1 << (XINT (category) % 8);
 317
 318     if (NILP (val))
 319       XCATEGORY_SET (category_set)->data[idx] &= ~bits;
 320     else
 321       XCATEGORY_SET (category_set)->data[idx] |= bits;
 322   } while (0);
 323 }
 324
 325 DEFUN ("modify-category-entry", Fmodify_category_entry,
 326        Smodify_category_entry, 2, 4, 0,
 327        doc: /* Modify the category set of CHARACTER by adding CATEGORY to it.
 328 The category is changed only for table TABLE, which defaults to
 329 the current buffer's category table.
 330 CHARACTER can be either a single character or a cons representing the
 331 lower and upper ends of an inclusive character range to modify.
 332 If optional fourth argument RESET is non-nil,
 333 then delete CATEGORY from the category set instead of adding it.  */)
 334      (character, category, table, reset)
 335      Lisp_Object character, category, table, reset;
 336 {
 337   Lisp_Object set_value;        /* Actual value to be set in category sets.  */
 338   Lisp_Object category_set;
 339   int start, end;
 340   int from, to;
 341
 342   if (INTEGERP (character))
 343     {
 344       CHECK_CHARACTER (character);
 345       start = end = XFASTINT (character);
 346     }
 347   else
 348     {
 349       CHECK_CONS (character);
 350       CHECK_CHARACTER (XCAR (character));
 351       CHECK_CHARACTER (XCDR (character));
 352       start = XFASTINT (XCAR (character));
 353       end = XFASTINT (XCDR (character));
 354     }
 355
 356   CHECK_CATEGORY (category);
 357   table = check_category_table (table);
 358
 359   if (NILP (CATEGORY_DOCSTRING (table, XFASTINT (category))))
 360     error ("Undefined category: %c", XFASTINT (category));
 361
 362   set_value = NILP (reset) ? Qt : Qnil;
 363
 364   while (start <= end)
 365     {
 366       category_set = char_table_ref_and_range (table, start, &from, &to);
 367       if (from < start || to > end)
 368         category_set = Fcopy_sequence (category_set);
 369       SET_CATEGORY_SET (category_set, category, set_value);
 370       if (from < start)
 371         {
 372           if (to > end)
 373             char_table_set_range (table, start, end, category_set);
 374           else
 375             char_table_set_range (table, start, to, category_set);
 376         }
 377       else if (to > end)
 378         char_table_set_range (table, start, end, category_set);
 379       start = to + 1;
 380     }
 381   return Qnil;
 382 }
 383 \f
 384 /* Return 1 if there is a word boundary between two word-constituent
 385    characters C1 and C2 if they appear in this order, else return 0.
 386    Use the macro WORD_BOUNDARY_P instead of calling this function
 387    directly.  */
 388
 389 int
 390 word_boundary_p (c1, c2)
 391      int c1, c2;
 392 {
 393   Lisp_Object category_set1, category_set2;
 394   Lisp_Object tail;
 395   int default_result;
 396
 397   if (CHAR_CHARSET (c1) == CHAR_CHARSET (c2))
 398     {
 399       tail = Vword_separating_categories;
 400       default_result = 0;
 401     }
 402   else
 403     {
 404       tail = Vword_combining_categories;
 405       default_result = 1;
 406     }
 407
 408   category_set1 = CATEGORY_SET (c1);
 409   if (NILP (category_set1))
 410     return default_result;
 411   category_set2 = CATEGORY_SET (c2);
 412   if (NILP (category_set2))
 413     return default_result;
 414
 415   for (; CONSP (tail); tail = XCDR (tail))
 416     {
 417       Lisp_Object elt = XCAR (tail);
 418
 419       if (CONSP (elt)
 420           && CATEGORYP (XCAR (elt))
 421           && CATEGORYP (XCDR (elt))
 422           && CATEGORY_MEMBER (XFASTINT (XCAR (elt)), category_set1)
 423           && CATEGORY_MEMBER (XFASTINT (XCDR (elt)), category_set2))
 424         return !default_result;
 425     }
 426   return default_result;
 427 }
 428
 429 \f
 430 void
 431 init_category_once ()
 432 {
 433   /* This has to be done here, before we call Fmake_char_table.  */
 434   Qcategory_table = intern ("category-table");
 435   staticpro (&Qcategory_table);
 436
 437   /* Intern this now in case it isn't already done.
 438      Setting this variable twice is harmless.
 439      But don't staticpro it here--that is done in alloc.c.  */
 440   Qchar_table_extra_slots = intern ("char-table-extra-slots");
 441
 442   /* Now we are ready to set up this property, so we can
 443      create category tables.  */
 444   Fput (Qcategory_table, Qchar_table_extra_slots, make_number (2));
 445
 446   Vstandard_category_table = Fmake_char_table (Qcategory_table, Qnil);
 447   /* Set a category set which contains nothing to the default.  */
 448   XCHAR_TABLE (Vstandard_category_table)->defalt = MAKE_CATEGORY_SET;
 449   Fset_char_table_extra_slot (Vstandard_category_table, make_number (0),
 450                               Fmake_vector (make_number (95), Qnil));
 451 }
 452
 453 void
 454 syms_of_category ()
 455 {
 456   Qcategoryp = intern ("categoryp");
 457   staticpro (&Qcategoryp);
 458   Qcategorysetp = intern ("categorysetp");
 459   staticpro (&Qcategorysetp);
 460   Qcategory_table_p = intern ("category-table-p");
 461   staticpro (&Qcategory_table_p);
 462
 463   DEFVAR_LISP ("word-combining-categories", &Vword_combining_categories,
 464                doc: /* List of pair (cons) of categories to determine word boundary.
 465
 466 Emacs treats a sequence of word constituent characters as a single
 467 word (i.e. finds no word boundary between them) iff they belongs to
 468 the same charset.  But, exceptions are allowed in the following cases.
 469
 470 \(1) The case that characters are in different charsets is controlled
 471 by the variable `word-combining-categories'.
 472
 473 Emacs finds no word boundary between characters of different charsets
 474 if they have categories matching some element of this list.
 475
 476 More precisely, if an element of this list is a cons of category CAT1
 477 and CAT2, and a multibyte character C1 which has CAT1 is followed by
 478 C2 which has CAT2, there's no word boundary between C1 and C2.
 479
 480 For instance, to tell that ASCII characters and Latin-1 characters can
 481 form a single word, the element `(?l . ?l)' should be in this list
 482 because both characters have the category `l' (Latin characters).
 483
 484 \(2) The case that character are in the same charset is controlled by
 485 the variable `word-separating-categories'.
 486
 487 Emacs find a word boundary between characters of the same charset
 488 if they have categories matching some element of this list.
 489
 490 More precisely, if an element of this list is a cons of category CAT1
 491 and CAT2, and a multibyte character C1 which has CAT1 is followed by
 492 C2 which has CAT2, there's a word boundary between C1 and C2.
 493
 494 For instance, to tell that there's a word boundary between Japanese
 495 Hiragana and Japanese Kanji (both are in the same charset), the
 496 element `(?H . ?C) should be in this list.  */);
 497
 498   Vword_combining_categories = Qnil;
 499
 500   DEFVAR_LISP ("word-separating-categories", &Vword_separating_categories,
 501                doc: /* List of pair (cons) of categories to determine word boundary.
 502 See the documentation of the variable `word-combining-categories'.  */);
 503
 504   Vword_separating_categories = Qnil;
 505
 506   defsubr (&Smake_category_set);
 507   defsubr (&Sdefine_category);
 508   defsubr (&Scategory_docstring);
 509   defsubr (&Sget_unused_category);
 510   defsubr (&Scategory_table_p);
 511   defsubr (&Scategory_table);
 512   defsubr (&Sstandard_category_table);
 513   defsubr (&Scopy_category_table);
 514   defsubr (&Smake_category_table);
 515   defsubr (&Sset_category_table);
 516   defsubr (&Schar_category_set);
 517   defsubr (&Scategory_set_mnemonics);
 518   defsubr (&Smodify_category_entry);
 519
 520   category_table_version = 0;
 521 }