| 1 | /* GNU Emacs routines to deal with case tables. |
| 2 | Copyright (C) 1993-1994, 2001-2011 Free Software Foundation, Inc. |
| 3 | |
| 4 | Author: Howard Gayle |
| 5 | |
| 6 | This file is part of GNU Emacs. |
| 7 | |
| 8 | GNU Emacs is free software: you can redistribute it and/or modify |
| 9 | it under the terms of the GNU General Public License as published by |
| 10 | the Free Software Foundation, either version 3 of the License, or |
| 11 | (at your option) any later version. |
| 12 | |
| 13 | GNU Emacs is distributed in the hope that it will be useful, |
| 14 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | GNU General Public License for more details. |
| 17 | |
| 18 | You should have received a copy of the GNU General Public License |
| 19 | along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */ |
| 20 | |
| 21 | #include <config.h> |
| 22 | #include <setjmp.h> |
| 23 | #include "lisp.h" |
| 24 | #include "buffer.h" |
| 25 | #include "character.h" |
| 26 | |
| 27 | static Lisp_Object Qcase_table_p, Qcase_table; |
| 28 | Lisp_Object Vascii_downcase_table; |
| 29 | static Lisp_Object Vascii_upcase_table; |
| 30 | Lisp_Object Vascii_canon_table; |
| 31 | static Lisp_Object Vascii_eqv_table; |
| 32 | |
| 33 | static void set_canon (Lisp_Object case_table, Lisp_Object range, Lisp_Object elt); |
| 34 | static void set_identity (Lisp_Object table, Lisp_Object c, Lisp_Object elt); |
| 35 | static void shuffle (Lisp_Object table, Lisp_Object c, Lisp_Object elt); |
| 36 | |
| 37 | DEFUN ("case-table-p", Fcase_table_p, Scase_table_p, 1, 1, 0, |
| 38 | doc: /* Return t if OBJECT is a case table. |
| 39 | See `set-case-table' for more information on these data structures. */) |
| 40 | (Lisp_Object object) |
| 41 | { |
| 42 | Lisp_Object up, canon, eqv; |
| 43 | |
| 44 | if (! CHAR_TABLE_P (object)) |
| 45 | return Qnil; |
| 46 | if (! EQ (XCHAR_TABLE (object)->purpose, Qcase_table)) |
| 47 | return Qnil; |
| 48 | |
| 49 | up = XCHAR_TABLE (object)->extras[0]; |
| 50 | canon = XCHAR_TABLE (object)->extras[1]; |
| 51 | eqv = XCHAR_TABLE (object)->extras[2]; |
| 52 | |
| 53 | return ((NILP (up) || CHAR_TABLE_P (up)) |
| 54 | && ((NILP (canon) && NILP (eqv)) |
| 55 | || (CHAR_TABLE_P (canon) |
| 56 | && (NILP (eqv) || CHAR_TABLE_P (eqv)))) |
| 57 | ? Qt : Qnil); |
| 58 | } |
| 59 | |
| 60 | static Lisp_Object |
| 61 | check_case_table (Lisp_Object obj) |
| 62 | { |
| 63 | CHECK_TYPE (!NILP (Fcase_table_p (obj)), Qcase_table_p, obj); |
| 64 | return (obj); |
| 65 | } |
| 66 | |
| 67 | DEFUN ("current-case-table", Fcurrent_case_table, Scurrent_case_table, 0, 0, 0, |
| 68 | doc: /* Return the case table of the current buffer. */) |
| 69 | (void) |
| 70 | { |
| 71 | return BVAR (current_buffer, downcase_table); |
| 72 | } |
| 73 | |
| 74 | DEFUN ("standard-case-table", Fstandard_case_table, Sstandard_case_table, 0, 0, 0, |
| 75 | doc: /* Return the standard case table. |
| 76 | This is the one used for new buffers. */) |
| 77 | (void) |
| 78 | { |
| 79 | return Vascii_downcase_table; |
| 80 | } |
| 81 | |
| 82 | static Lisp_Object set_case_table (Lisp_Object table, int standard); |
| 83 | |
| 84 | DEFUN ("set-case-table", Fset_case_table, Sset_case_table, 1, 1, 0, |
| 85 | doc: /* Select a new case table for the current buffer. |
| 86 | A case table is a char-table which maps characters |
| 87 | to their lower-case equivalents. It also has three \"extra\" slots |
| 88 | which may be additional char-tables or nil. |
| 89 | These slots are called UPCASE, CANONICALIZE and EQUIVALENCES. |
| 90 | UPCASE maps each non-upper-case character to its upper-case equivalent. |
| 91 | (The value in UPCASE for an upper-case character is never used.) |
| 92 | If lower and upper case characters are in 1-1 correspondence, |
| 93 | you may use nil and the upcase table will be deduced from DOWNCASE. |
| 94 | CANONICALIZE maps each character to a canonical equivalent; |
| 95 | any two characters that are related by case-conversion have the same |
| 96 | canonical equivalent character; it may be nil, in which case it is |
| 97 | deduced from DOWNCASE and UPCASE. |
| 98 | EQUIVALENCES is a map that cyclicly permutes each equivalence class |
| 99 | (of characters with the same canonical equivalent); it may be nil, |
| 100 | in which case it is deduced from CANONICALIZE. */) |
| 101 | (Lisp_Object table) |
| 102 | { |
| 103 | return set_case_table (table, 0); |
| 104 | } |
| 105 | |
| 106 | DEFUN ("set-standard-case-table", Fset_standard_case_table, |
| 107 | Sset_standard_case_table, 1, 1, 0, |
| 108 | doc: /* Select a new standard case table for new buffers. |
| 109 | See `set-case-table' for more info on case tables. */) |
| 110 | (Lisp_Object table) |
| 111 | { |
| 112 | return set_case_table (table, 1); |
| 113 | } |
| 114 | |
| 115 | static Lisp_Object |
| 116 | set_case_table (Lisp_Object table, int standard) |
| 117 | { |
| 118 | Lisp_Object up, canon, eqv; |
| 119 | |
| 120 | check_case_table (table); |
| 121 | |
| 122 | up = XCHAR_TABLE (table)->extras[0]; |
| 123 | canon = XCHAR_TABLE (table)->extras[1]; |
| 124 | eqv = XCHAR_TABLE (table)->extras[2]; |
| 125 | |
| 126 | if (NILP (up)) |
| 127 | { |
| 128 | up = Fmake_char_table (Qcase_table, Qnil); |
| 129 | map_char_table (set_identity, Qnil, table, up); |
| 130 | map_char_table (shuffle, Qnil, table, up); |
| 131 | XCHAR_TABLE (table)->extras[0] = up; |
| 132 | } |
| 133 | |
| 134 | if (NILP (canon)) |
| 135 | { |
| 136 | canon = Fmake_char_table (Qcase_table, Qnil); |
| 137 | XCHAR_TABLE (table)->extras[1] = canon; |
| 138 | map_char_table (set_canon, Qnil, table, table); |
| 139 | } |
| 140 | |
| 141 | if (NILP (eqv)) |
| 142 | { |
| 143 | eqv = Fmake_char_table (Qcase_table, Qnil); |
| 144 | map_char_table (set_identity, Qnil, canon, eqv); |
| 145 | map_char_table (shuffle, Qnil, canon, eqv); |
| 146 | XCHAR_TABLE (table)->extras[2] = eqv; |
| 147 | } |
| 148 | |
| 149 | /* This is so set_image_of_range_1 in regex.c can find the EQV table. */ |
| 150 | XCHAR_TABLE (canon)->extras[2] = eqv; |
| 151 | |
| 152 | if (standard) |
| 153 | { |
| 154 | Vascii_downcase_table = table; |
| 155 | Vascii_upcase_table = up; |
| 156 | Vascii_canon_table = canon; |
| 157 | Vascii_eqv_table = eqv; |
| 158 | } |
| 159 | else |
| 160 | { |
| 161 | BVAR (current_buffer, downcase_table) = table; |
| 162 | BVAR (current_buffer, upcase_table) = up; |
| 163 | BVAR (current_buffer, case_canon_table) = canon; |
| 164 | BVAR (current_buffer, case_eqv_table) = eqv; |
| 165 | } |
| 166 | |
| 167 | return table; |
| 168 | } |
| 169 | \f |
| 170 | /* The following functions are called in map_char_table. */ |
| 171 | |
| 172 | /* Set CANON char-table element for characters in RANGE to a |
| 173 | translated ELT by UP and DOWN char-tables. This is done only when |
| 174 | ELT is a character. The char-tables CANON, UP, and DOWN are in |
| 175 | CASE_TABLE. */ |
| 176 | |
| 177 | static void |
| 178 | set_canon (Lisp_Object case_table, Lisp_Object range, Lisp_Object elt) |
| 179 | { |
| 180 | Lisp_Object up = XCHAR_TABLE (case_table)->extras[0]; |
| 181 | Lisp_Object canon = XCHAR_TABLE (case_table)->extras[1]; |
| 182 | |
| 183 | if (NATNUMP (elt)) |
| 184 | Fset_char_table_range (canon, range, Faref (case_table, Faref (up, elt))); |
| 185 | } |
| 186 | |
| 187 | /* Set elements of char-table TABLE for C to C itself. C may be a |
| 188 | cons specifying a character range. In that case, set characters in |
| 189 | that range to themselves. This is done only when ELT is a |
| 190 | character. This is called in map_char_table. */ |
| 191 | |
| 192 | static void |
| 193 | set_identity (Lisp_Object table, Lisp_Object c, Lisp_Object elt) |
| 194 | { |
| 195 | if (NATNUMP (elt)) |
| 196 | { |
| 197 | int from; |
| 198 | int to; |
| 199 | |
| 200 | if (CONSP (c)) |
| 201 | { |
| 202 | from = XINT (XCAR (c)); |
| 203 | to = XINT (XCDR (c)); |
| 204 | } |
| 205 | else |
| 206 | from = to = XINT (c); |
| 207 | for (; from <= to; from++) |
| 208 | CHAR_TABLE_SET (table, from, make_number (from)); |
| 209 | } |
| 210 | } |
| 211 | |
| 212 | /* Permute the elements of TABLE (which is initially an identity |
| 213 | mapping) so that it has one cycle for each equivalence class |
| 214 | induced by the translation table on which map_char_table is |
| 215 | operated. */ |
| 216 | |
| 217 | static void |
| 218 | shuffle (Lisp_Object table, Lisp_Object c, Lisp_Object elt) |
| 219 | { |
| 220 | if (NATNUMP (elt)) |
| 221 | { |
| 222 | int from, to; |
| 223 | |
| 224 | if (CONSP (c)) |
| 225 | { |
| 226 | from = XINT (XCAR (c)); |
| 227 | to = XINT (XCDR (c)); |
| 228 | } |
| 229 | else |
| 230 | from = to = XINT (c); |
| 231 | |
| 232 | for (; from <= to; from++) |
| 233 | { |
| 234 | Lisp_Object tem = Faref (table, elt); |
| 235 | Faset (table, elt, make_number (from)); |
| 236 | Faset (table, make_number (from), tem); |
| 237 | } |
| 238 | } |
| 239 | } |
| 240 | \f |
| 241 | void |
| 242 | init_casetab_once (void) |
| 243 | { |
| 244 | register int i; |
| 245 | Lisp_Object down, up; |
| 246 | DEFSYM (Qcase_table, "case-table"); |
| 247 | |
| 248 | /* Intern this now in case it isn't already done. |
| 249 | Setting this variable twice is harmless. |
| 250 | But don't staticpro it here--that is done in alloc.c. */ |
| 251 | Qchar_table_extra_slots = intern_c_string ("char-table-extra-slots"); |
| 252 | |
| 253 | /* Now we are ready to set up this property, so we can |
| 254 | create char tables. */ |
| 255 | Fput (Qcase_table, Qchar_table_extra_slots, make_number (3)); |
| 256 | |
| 257 | down = Fmake_char_table (Qcase_table, Qnil); |
| 258 | Vascii_downcase_table = down; |
| 259 | XCHAR_TABLE (down)->purpose = Qcase_table; |
| 260 | |
| 261 | for (i = 0; i < 128; i++) |
| 262 | { |
| 263 | int c = (i >= 'A' && i <= 'Z') ? i + ('a' - 'A') : i; |
| 264 | CHAR_TABLE_SET (down, i, make_number (c)); |
| 265 | } |
| 266 | |
| 267 | XCHAR_TABLE (down)->extras[1] = Fcopy_sequence (down); |
| 268 | |
| 269 | up = Fmake_char_table (Qcase_table, Qnil); |
| 270 | XCHAR_TABLE (down)->extras[0] = up; |
| 271 | |
| 272 | for (i = 0; i < 128; i++) |
| 273 | { |
| 274 | int c = ((i >= 'A' && i <= 'Z') ? i + ('a' - 'A') |
| 275 | : ((i >= 'a' && i <= 'z') ? i + ('A' - 'a') |
| 276 | : i)); |
| 277 | CHAR_TABLE_SET (up, i, make_number (c)); |
| 278 | } |
| 279 | |
| 280 | XCHAR_TABLE (down)->extras[2] = Fcopy_sequence (up); |
| 281 | |
| 282 | /* Fill in what isn't filled in. */ |
| 283 | set_case_table (down, 1); |
| 284 | } |
| 285 | |
| 286 | void |
| 287 | syms_of_casetab (void) |
| 288 | { |
| 289 | DEFSYM (Qcase_table_p, "case-table-p"); |
| 290 | |
| 291 | staticpro (&Vascii_canon_table); |
| 292 | staticpro (&Vascii_downcase_table); |
| 293 | staticpro (&Vascii_eqv_table); |
| 294 | staticpro (&Vascii_upcase_table); |
| 295 | |
| 296 | defsubr (&Scase_table_p); |
| 297 | defsubr (&Scurrent_case_table); |
| 298 | defsubr (&Sstandard_case_table); |
| 299 | defsubr (&Sset_case_table); |
| 300 | defsubr (&Sset_standard_case_table); |
| 301 | } |