% writeenc.w
% 
% Copyright 1996-2006 Han The Thanh <thanh@@pdftex.org>
% Copyright 2006-2008 Taco Hoekwater <taco@@luatex.org>

% This file is part of LuaTeX.

% LuaTeX 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 2 of the License, or (at your
% option) any later version.

% LuaTeX 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 Lesser General Public
% License for more details.

% You should have received a copy of the GNU General Public License along
% with LuaTeX; if not, see <http://www.gnu.org/licenses/>. */

@ @c
#include "ptexlib.h"

static const char _svn_version[] =
    "$Id: writeenc.w 3615 2010-04-13 21:59:59Z oneiros $ "
"$URL: http://foundry.supelec.fr/svn/luatex/tags/beta-0.70.1/source/texk/web2c/luatexdir/font/writeenc.w $";

@ All encoding entries go into AVL tree for fast search by name. 
@c
struct avl_table *fe_tree = NULL;

@ AVL sort |fe_entry| into |fe_tree| by name
@c
static int comp_fe_entry(const void *pa, const void *pb, void *p)
{
    (void) p;
    return strcmp(((const fe_entry *) pa)->name, ((const fe_entry *) pb)->name);
}

static fe_entry *new_fe_entry(void)
{
    fe_entry *fe;
    fe = xtalloc(1, fe_entry);
    fe->name = NULL;
    fe->fe_objnum = 0;
    fe->glyph_names = NULL;     /* encoding file not yet read in */
    fe->tx_tree = NULL;
    return fe;
}

static fe_entry *lookup_fe_entry(char *s)
{
    fe_entry fe;
    assert(s != NULL);
    fe.name = s;
    if (fe_tree == NULL) {
        fe_tree = avl_create(comp_fe_entry, NULL, &avl_xallocator);
        assert(fe_tree != NULL);
    }
    return (fe_entry *) avl_find(fe_tree, &fe);
}

static void register_fe_entry(fe_entry * fe)
{
    void **aa;
    if (fe_tree == NULL) {
        fe_tree = avl_create(comp_fe_entry, NULL, &avl_xallocator);
        assert(fe_tree != NULL);
    }
    assert(fe != NULL);
    assert(fe->name != NULL);
    assert(lookup_fe_entry(fe->name) == NULL);  /* encoding not yet registered */
    aa = avl_probe(fe_tree, fe);
    assert(aa != NULL);
}

fe_entry *get_fe_entry(char *s)
{
    fe_entry *fe;
    char **gl;
    if ((fe = lookup_fe_entry(s)) == NULL && (gl = load_enc_file(s)) != NULL) {
        fe = new_fe_entry();
        fe->name = s;
        fe->glyph_names = gl;
        register_fe_entry(fe);
    }
    return fe;
}

@ @c
static void write_enc(PDF pdf, char **glyph_names, struct avl_table *tx_tree,
               int fe_objnum)
{
    int i_old, *p;
    struct avl_traverser t;
    assert(glyph_names != NULL);
    assert(tx_tree != NULL);
    assert(fe_objnum != 0);
    pdf_begin_dict(pdf, fe_objnum, 1);
    pdf_puts(pdf, "/Type /Encoding\n");
    pdf_puts(pdf, "/Differences [");
    avl_t_init(&t, tx_tree);
    for (i_old = -2, p = (int *) avl_t_first(&t, tx_tree); p != NULL;
         p = (int *) avl_t_next(&t)) {
        if (*p == i_old + 1)    /* no gap */
            pdf_printf(pdf, "/%s", glyph_names[*p]);
        else {
            if (i_old == -2)
                pdf_printf(pdf, "%i/%s", *p, glyph_names[*p]);
            else
                pdf_printf(pdf, " %i/%s", *p, glyph_names[*p]);
        }
        i_old = *p;
    }
    pdf_puts(pdf, "]\n");
    pdf_end_dict(pdf);
}

static void write_fontencoding(PDF pdf, fe_entry * fe)
{
    assert(fe != NULL);
    write_enc(pdf, fe->glyph_names, fe->tx_tree, fe->fe_objnum);
}

void write_fontencodings(PDF pdf)
{
    fe_entry *fe;
    struct avl_traverser t;
    if (fe_tree == NULL)
        return;
    avl_t_init(&t, fe_tree);
    for (fe = (fe_entry *) avl_t_first(&t, fe_tree); fe != NULL;
         fe = (fe_entry *) avl_t_next(&t))
        if (fe->fe_objnum != 0)
            write_fontencoding(pdf, fe);
}

@ cleaning up... 
@c

static void destroy_fe_entry(void *pa, void *pb)
{
    fe_entry *p;
    int i;
    (void) pb;
    p = (fe_entry *) pa;
    xfree(p->name);
    if (p->glyph_names != NULL)
        for (i = 0; i < 256; i++)
            if (p->glyph_names[i] != notdef)
                xfree(p->glyph_names[i]);
    xfree(p->glyph_names);
    xfree(p);
}

void enc_free(void)
{
    if (fe_tree != NULL)
        avl_destroy(fe_tree, destroy_fe_entry);
    fe_tree = NULL;
}