/* GNU Emacs routines to deal with case tables.
Copyright (C) 1993-1994, 2001-2014 Free Software Foundation, Inc.
Author: Howard Gayle
This file is part of GNU Emacs.
GNU Emacs is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */
#include <config.h>
#include "lisp.h"
#include "character.h"
#include "buffer.h"
static Lisp_Object Qcase_table_p, Qcase_table;
Lisp_Object Vascii_downcase_table;
static Lisp_Object Vascii_upcase_table;
Lisp_Object Vascii_canon_table;
static Lisp_Object Vascii_eqv_table;
static void set_canon (Lisp_Object case_table, Lisp_Object range, Lisp_Object elt);
static void set_identity (Lisp_Object table, Lisp_Object c, Lisp_Object elt);
static void shuffle (Lisp_Object table, Lisp_Object c, Lisp_Object elt);
DEFUN ("case-table-p", Fcase_table_p, Scase_table_p, 1, 1, 0,
doc: /* Return t if OBJECT is a case table.
See `set-case-table' for more information on these data structures. */)
(Lisp_Object object)
{
Lisp_Object up, canon, eqv;
if (! CHAR_TABLE_P (object))
return Qnil;
if (! EQ (XCHAR_TABLE (object)->purpose, Qcase_table))
return Qnil;
up = XCHAR_TABLE (object)->extras[0];
canon = XCHAR_TABLE (object)->extras[1];
eqv = XCHAR_TABLE (object)->extras[2];
return ((NILP (up) || CHAR_TABLE_P (up))
&& ((NILP (canon) && NILP (eqv))
|| (CHAR_TABLE_P (canon)
&& (NILP (eqv) || CHAR_TABLE_P (eqv))))
? Qt : Qnil);
}
static Lisp_Object
check_case_table (Lisp_Object obj)
{
CHECK_TYPE (!NILP (Fcase_table_p (obj)), Qcase_table_p, obj);
return (obj);
}
DEFUN ("current-case-table", Fcurrent_case_table, Scurrent_case_table, 0, 0, 0,
doc: /* Return the case table of the current buffer. */)
(void)
{
return BVAR (current_buffer, downcase_table);
}
DEFUN ("standard-case-table", Fstandard_case_table, Sstandard_case_table, 0, 0, 0,
doc: /* Return the standard case table.
This is the one used for new buffers. */)
(void)
{
return Vascii_downcase_table;
}
static Lisp_Object set_case_table (Lisp_Object, bool);
DEFUN ("set-case-table", Fset_case_table, Sset_case_table, 1, 1, 0,
doc: /* Select a new case table for the current buffer.
A case table is a char-table which maps characters
to their lower-case equivalents. It also has three \"extra\" slots
which may be additional char-tables or nil.
These slots are called UPCASE, CANONICALIZE and EQUIVALENCES.
UPCASE maps each non-upper-case character to its upper-case equivalent.
(The value in UPCASE for an upper-case character is never used.)
If lower and upper case characters are in 1-1 correspondence,
you may use nil and the upcase table will be deduced from DOWNCASE.
CANONICALIZE maps each character to a canonical equivalent;
any two characters that are related by case-conversion have the same
canonical equivalent character; it may be nil, in which case it is
deduced from DOWNCASE and UPCASE.
EQUIVALENCES is a map that cyclically permutes each equivalence class
(of characters with the same canonical equivalent); it may be nil,
in which case it is deduced from CANONICALIZE. */)
(Lisp_Object table)
{
return set_case_table (table, 0);
}
DEFUN ("set-standard-case-table", Fset_standard_case_table,
Sset_standard_case_table, 1, 1, 0,
doc: /* Select a new standard case table for new buffers.
See `set-case-table' for more info on case tables. */)
(Lisp_Object table)
{
return set_case_table (table, 1);
}
static Lisp_Object
set_case_table (Lisp_Object table, bool standard)
{
Lisp_Object up, canon, eqv;
check_case_table (table);
up = XCHAR_TABLE (table)->extras[0];
canon = XCHAR_TABLE (table)->extras[1];
eqv = XCHAR_TABLE (table)->extras[2];
if (NILP (up))
{
up = Fmake_char_table (Qcase_table, Qnil);
map_char_table (set_identity, Qnil, table, up);
map_char_table (shuffle, Qnil, table, up);
set_char_table_extras (table, 0, up);
}
if (NILP (canon))
{
canon = Fmake_char_table (Qcase_table, Qnil);
set_char_table_extras (table, 1, canon);
map_char_table (set_canon, Qnil, table, table);
}
if (NILP (eqv))
{
eqv = Fmake_char_table (Qcase_table, Qnil);
map_char_table (set_identity, Qnil, canon, eqv);
map_char_table (shuffle, Qnil, canon, eqv);
set_char_table_extras (table, 2, eqv);
}
/* This is so set_image_of_range_1 in regex.c can find the EQV table. */
set_char_table_extras (canon, 2, eqv);
if (standard)
{
Vascii_downcase_table = table;
Vascii_upcase_table = up;
Vascii_canon_table = canon;
Vascii_eqv_table = eqv;
}
else
{
bset_downcase_table (current_buffer, table);
bset_upcase_table (current_buffer, up);
bset_case_canon_table (current_buffer, canon);
bset_case_eqv_table (current_buffer, eqv);
}
return table;
}
/* The following functions are called in map_char_table. */
/* Set CANON char-table element for characters in RANGE to a
translated ELT by UP and DOWN char-tables. This is done only when
ELT is a character. The char-tables CANON, UP, and DOWN are in
CASE_TABLE. */
static void
set_canon (Lisp_Object case_table, Lisp_Object range, Lisp_Object elt)
{
Lisp_Object up = XCHAR_TABLE (case_table)->extras[0];
Lisp_Object canon = XCHAR_TABLE (case_table)->extras[1];
if (NATNUMP (elt))
Fset_char_table_range (canon, range, Faref (case_table, Faref (up, elt)));
}
/* Set elements of char-table TABLE for C to C itself. C may be a
cons specifying a character range. In that case, set characters in
that range to themselves. This is done only when ELT is a
character. This is called in map_char_table. */
static void
set_identity (Lisp_Object table, Lisp_Object c, Lisp_Object elt)
{
if (NATNUMP (elt))
{
int from, to;
if (CONSP (c))
{
from = XINT (XCAR (c));
to = XINT (XCDR (c));
}
else
from = to = XINT (c);
to++;
for (; from < to; from++)
CHAR_TABLE_SET (table, from, make_number (from));
}
}
/* Permute the elements of TABLE (which is initially an identity
mapping) so that it has one cycle for each equivalence class
induced by the translation table on which map_char_table is
operated. */
static void
shuffle (Lisp_Object table, Lisp_Object c, Lisp_Object elt)
{
if (NATNUMP (elt))
{
int from, to;
if (CONSP (c))
{
from = XINT (XCAR (c));
to = XINT (XCDR (c));
}
else
from = to = XINT (c);
to++;
for (; from < to; from++)
{
Lisp_Object tem = Faref (table, elt);
Faset (table, elt, make_number (from));
Faset (table, make_number (from), tem);
}
}
}
void
init_casetab_once (void)
{
register int i;
Lisp_Object down, up, eqv;
DEFSYM (Qcase_table, "case-table");
Fput (Qcase_table, Qchar_table_extra_slots, make_number (3));
down = Fmake_char_table (Qcase_table, Qnil);
Vascii_downcase_table = down;
set_char_table_purpose (down, Qcase_table);
for (i = 0; i < 128; i++)
{
int c = (i >= 'A' && i <= 'Z') ? i + ('a' - 'A') : i;
CHAR_TABLE_SET (down, i, make_number (c));
}
set_char_table_extras (down, 1, Fcopy_sequence (down));
up = Fmake_char_table (Qcase_table, Qnil);
set_char_table_extras (down, 0, up);
for (i = 0; i < 128; i++)
{
int c = (i >= 'a' && i <= 'z') ? i + ('A' - 'a') : i;
CHAR_TABLE_SET (up, i, make_number (c));
}
eqv = Fmake_char_table (Qcase_table, Qnil);
for (i = 0; i < 128; i++)
{
int c = ((i >= 'A' && i <= 'Z') ? i + ('a' - 'A')
: ((i >= 'a' && i <= 'z') ? i + ('A' - 'a')
: i));
CHAR_TABLE_SET (eqv, i, make_number (c));
}
set_char_table_extras (down, 2, eqv);
/* Fill in what isn't filled in. */
set_case_table (down, 1);
}
void
syms_of_casetab (void)
{
DEFSYM (Qcase_table_p, "case-table-p");
staticpro (&Vascii_canon_table);
staticpro (&Vascii_downcase_table);
staticpro (&Vascii_eqv_table);
staticpro (&Vascii_upcase_table);
defsubr (&Scase_table_p);
defsubr (&Scurrent_case_table);
defsubr (&Sstandard_case_table);
defsubr (&Sset_case_table);
defsubr (&Sset_standard_case_table);
}