| 1 | /* GNU Emacs routines to deal with case tables. |
| 2 | Copyright (C) 1993, 1994 Free Software Foundation, Inc. |
| 3 | |
| 4 | This file is part of GNU Emacs. |
| 5 | |
| 6 | GNU Emacs is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by |
| 8 | the Free Software Foundation; either version 2, or (at your option) |
| 9 | any later version. |
| 10 | |
| 11 | GNU Emacs is distributed in the hope that it will be useful, |
| 12 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 14 | GNU General Public License for more details. |
| 15 | |
| 16 | You should have received a copy of the GNU General Public License |
| 17 | along with GNU Emacs; see the file COPYING. If not, write to |
| 18 | the Free Software Foundation, Inc., 59 Temple Place - Suite 330, |
| 19 | Boston, MA 02111-1307, USA. */ |
| 20 | |
| 21 | /* Written by Howard Gayle. See chartab.c for details. */ |
| 22 | |
| 23 | #include <config.h> |
| 24 | #include "lisp.h" |
| 25 | #include "buffer.h" |
| 26 | #include "charset.h" |
| 27 | |
| 28 | Lisp_Object Qcase_table_p, Qcase_table; |
| 29 | Lisp_Object Vascii_downcase_table, Vascii_upcase_table; |
| 30 | Lisp_Object Vascii_canon_table, Vascii_eqv_table; |
| 31 | |
| 32 | /* Used as a temporary in DOWNCASE and other macros in lisp.h. No |
| 33 | need to mark it, since it is used only very temporarily. */ |
| 34 | int case_temp1; |
| 35 | Lisp_Object case_temp2; |
| 36 | |
| 37 | static void set_canon (); |
| 38 | static void set_identity (); |
| 39 | static void shuffle (); |
| 40 | |
| 41 | DEFUN ("case-table-p", Fcase_table_p, Scase_table_p, 1, 1, 0, |
| 42 | doc: /* Return t iff OBJECT is a case table. |
| 43 | See `set-case-table' for more information on these data structures. */) |
| 44 | (object) |
| 45 | Lisp_Object object; |
| 46 | { |
| 47 | Lisp_Object up, canon, eqv; |
| 48 | |
| 49 | if (! CHAR_TABLE_P (object)) |
| 50 | return Qnil; |
| 51 | if (! EQ (XCHAR_TABLE (object)->purpose, Qcase_table)) |
| 52 | return Qnil; |
| 53 | |
| 54 | up = XCHAR_TABLE (object)->extras[0]; |
| 55 | canon = XCHAR_TABLE (object)->extras[1]; |
| 56 | eqv = XCHAR_TABLE (object)->extras[2]; |
| 57 | |
| 58 | return ((NILP (up) || CHAR_TABLE_P (up)) |
| 59 | && ((NILP (canon) && NILP (eqv)) |
| 60 | || (CHAR_TABLE_P (canon) |
| 61 | && (NILP (eqv) || CHAR_TABLE_P (eqv)))) |
| 62 | ? Qt : Qnil); |
| 63 | } |
| 64 | |
| 65 | static Lisp_Object |
| 66 | check_case_table (obj) |
| 67 | Lisp_Object obj; |
| 68 | { |
| 69 | register Lisp_Object tem; |
| 70 | |
| 71 | while (tem = Fcase_table_p (obj), NILP (tem)) |
| 72 | obj = wrong_type_argument (Qcase_table_p, obj); |
| 73 | return (obj); |
| 74 | } |
| 75 | |
| 76 | DEFUN ("current-case-table", Fcurrent_case_table, Scurrent_case_table, 0, 0, 0, |
| 77 | doc: /* Return the case table of the current buffer. */) |
| 78 | () |
| 79 | { |
| 80 | return current_buffer->downcase_table; |
| 81 | } |
| 82 | |
| 83 | DEFUN ("standard-case-table", Fstandard_case_table, Sstandard_case_table, 0, 0, 0, |
| 84 | doc: /* Return the standard case table. |
| 85 | This is the one used for new buffers. */) |
| 86 | () |
| 87 | { |
| 88 | return Vascii_downcase_table; |
| 89 | } |
| 90 | |
| 91 | static Lisp_Object set_case_table (); |
| 92 | |
| 93 | DEFUN ("set-case-table", Fset_case_table, Sset_case_table, 1, 1, 0, |
| 94 | doc: /* Select a new case table for the current buffer. |
| 95 | A case table is a char-table which maps characters |
| 96 | to their lower-case equivalents. It also has three \"extra\" slots |
| 97 | which may be additional char-tables or nil. |
| 98 | These slots are called UPCASE, CANONICALIZE and EQUIVALENCES. |
| 99 | UPCASE maps each character to its upper-case equivalent; |
| 100 | if lower and upper case characters are in 1-1 correspondence, |
| 101 | you may use nil and the upcase table will be deduced from DOWNCASE. |
| 102 | CANONICALIZE maps each character to a canonical equivalent; |
| 103 | any two characters that are related by case-conversion have the same |
| 104 | canonical equivalent character; it may be nil, in which case it is |
| 105 | deduced from DOWNCASE and UPCASE. |
| 106 | EQUIVALENCES is a map that cyclicly permutes each equivalence class |
| 107 | (of characters with the same canonical equivalent); it may be nil, |
| 108 | in which case it is deduced from CANONICALIZE. */) |
| 109 | (table) |
| 110 | Lisp_Object table; |
| 111 | { |
| 112 | return set_case_table (table, 0); |
| 113 | } |
| 114 | |
| 115 | DEFUN ("set-standard-case-table", Fset_standard_case_table, Sset_standard_case_table, 1, 1, 0, |
| 116 | doc: /* Select a new standard case table for new buffers. |
| 117 | See `set-case-table' for more info on case tables. */) |
| 118 | (table) |
| 119 | Lisp_Object table; |
| 120 | { |
| 121 | return set_case_table (table, 1); |
| 122 | } |
| 123 | |
| 124 | static Lisp_Object |
| 125 | set_case_table (table, standard) |
| 126 | Lisp_Object table; |
| 127 | int standard; |
| 128 | { |
| 129 | Lisp_Object up, canon, eqv; |
| 130 | Lisp_Object indices[3]; |
| 131 | |
| 132 | check_case_table (table); |
| 133 | |
| 134 | up = XCHAR_TABLE (table)->extras[0]; |
| 135 | canon = XCHAR_TABLE (table)->extras[1]; |
| 136 | eqv = XCHAR_TABLE (table)->extras[2]; |
| 137 | |
| 138 | if (NILP (up)) |
| 139 | { |
| 140 | up = Fmake_char_table (Qcase_table, Qnil); |
| 141 | map_char_table (set_identity, Qnil, table, up, 0, indices); |
| 142 | map_char_table (shuffle, Qnil, table, up, 0, indices); |
| 143 | XCHAR_TABLE (table)->extras[0] = up; |
| 144 | } |
| 145 | |
| 146 | if (NILP (canon)) |
| 147 | { |
| 148 | canon = Fmake_char_table (Qcase_table, Qnil); |
| 149 | XCHAR_TABLE (table)->extras[1] = canon; |
| 150 | map_char_table (set_canon, Qnil, table, table, 0, indices); |
| 151 | } |
| 152 | |
| 153 | if (NILP (eqv)) |
| 154 | { |
| 155 | eqv = Fmake_char_table (Qcase_table, Qnil); |
| 156 | map_char_table (set_identity, Qnil, canon, eqv, 0, indices); |
| 157 | map_char_table (shuffle, Qnil, canon, eqv, 0, indices); |
| 158 | XCHAR_TABLE (table)->extras[2] = eqv; |
| 159 | } |
| 160 | |
| 161 | if (standard) |
| 162 | Vascii_downcase_table = table; |
| 163 | else |
| 164 | { |
| 165 | current_buffer->downcase_table = table; |
| 166 | current_buffer->upcase_table = up; |
| 167 | current_buffer->case_canon_table = canon; |
| 168 | current_buffer->case_eqv_table = eqv; |
| 169 | } |
| 170 | |
| 171 | return table; |
| 172 | } |
| 173 | \f |
| 174 | /* The following functions are called in map_char_table. */ |
| 175 | |
| 176 | /* Set CANON char-table element for C to a translated ELT by UP and |
| 177 | DOWN char-tables. This is done only when ELT is a character. The |
| 178 | char-tables CANON, UP, and DOWN are in CASE_TABLE. */ |
| 179 | |
| 180 | static void |
| 181 | set_canon (case_table, c, elt) |
| 182 | Lisp_Object case_table, c, elt; |
| 183 | { |
| 184 | Lisp_Object up = XCHAR_TABLE (case_table)->extras[0]; |
| 185 | Lisp_Object canon = XCHAR_TABLE (case_table)->extras[1]; |
| 186 | |
| 187 | if (NATNUMP (elt)) |
| 188 | Faset (canon, c, Faref (case_table, Faref (up, elt))); |
| 189 | } |
| 190 | |
| 191 | /* Set elements of char-table TABLE for C to C itself. This is done |
| 192 | only when ELT is a character. This is called in map_char_table. */ |
| 193 | |
| 194 | static void |
| 195 | set_identity (table, c, elt) |
| 196 | Lisp_Object table, c, elt; |
| 197 | { |
| 198 | if (NATNUMP (elt)) |
| 199 | Faset (table, c, c); |
| 200 | } |
| 201 | |
| 202 | /* Permute the elements of TABLE (which is initially an identity |
| 203 | mapping) so that it has one cycle for each equivalence class |
| 204 | induced by the translation table on which map_char_table is |
| 205 | operated. */ |
| 206 | |
| 207 | static void |
| 208 | shuffle (table, c, elt) |
| 209 | Lisp_Object table, c, elt; |
| 210 | { |
| 211 | if (NATNUMP (elt) && !EQ (c, elt)) |
| 212 | { |
| 213 | Lisp_Object tem = Faref (table, elt); |
| 214 | Faset (table, elt, c); |
| 215 | Faset (table, c, tem); |
| 216 | } |
| 217 | } |
| 218 | \f |
| 219 | void |
| 220 | init_casetab_once () |
| 221 | { |
| 222 | register int i; |
| 223 | Lisp_Object down, up; |
| 224 | Qcase_table = intern ("case-table"); |
| 225 | staticpro (&Qcase_table); |
| 226 | |
| 227 | /* Intern this now in case it isn't already done. |
| 228 | Setting this variable twice is harmless. |
| 229 | But don't staticpro it here--that is done in alloc.c. */ |
| 230 | Qchar_table_extra_slots = intern ("char-table-extra-slots"); |
| 231 | |
| 232 | /* Now we are ready to set up this property, so we can |
| 233 | create char tables. */ |
| 234 | Fput (Qcase_table, Qchar_table_extra_slots, make_number (3)); |
| 235 | |
| 236 | down = Fmake_char_table (Qcase_table, Qnil); |
| 237 | Vascii_downcase_table = down; |
| 238 | XCHAR_TABLE (down)->purpose = Qcase_table; |
| 239 | |
| 240 | for (i = 0; i < CHAR_TABLE_SINGLE_BYTE_SLOTS; i++) |
| 241 | XSETFASTINT (XCHAR_TABLE (down)->contents[i], |
| 242 | (i >= 'A' && i <= 'Z') ? i + ('a' - 'A') : i); |
| 243 | |
| 244 | XCHAR_TABLE (down)->extras[1] = Fcopy_sequence (down); |
| 245 | |
| 246 | up = Fmake_char_table (Qcase_table, Qnil); |
| 247 | XCHAR_TABLE (down)->extras[0] = up; |
| 248 | |
| 249 | for (i = 0; i < CHAR_TABLE_SINGLE_BYTE_SLOTS; i++) |
| 250 | XSETFASTINT (XCHAR_TABLE (up)->contents[i], |
| 251 | ((i >= 'A' && i <= 'Z') |
| 252 | ? i + ('a' - 'A') |
| 253 | : ((i >= 'a' && i <= 'z') |
| 254 | ? i + ('A' - 'a') |
| 255 | : i))); |
| 256 | |
| 257 | XCHAR_TABLE (down)->extras[2] = Fcopy_sequence (up); |
| 258 | } |
| 259 | |
| 260 | void |
| 261 | syms_of_casetab () |
| 262 | { |
| 263 | Qcase_table_p = intern ("case-table-p"); |
| 264 | staticpro (&Qcase_table_p); |
| 265 | |
| 266 | staticpro (&Vascii_canon_table); |
| 267 | staticpro (&Vascii_downcase_table); |
| 268 | staticpro (&Vascii_eqv_table); |
| 269 | staticpro (&Vascii_upcase_table); |
| 270 | |
| 271 | defsubr (&Scase_table_p); |
| 272 | defsubr (&Scurrent_case_table); |
| 273 | defsubr (&Sstandard_case_table); |
| 274 | defsubr (&Sset_case_table); |
| 275 | defsubr (&Sset_standard_case_table); |
| 276 | } |