source/texk/web2c/luatexdir/font/dofont.w

   1 % dofont.w
   2 %
   3 % Copyright 2006-2010 Taco Hoekwater <taco@@luatex.org>
   4 %
   5 % This file is part of LuaTeX.
   6 %
   7 % LuaTeX is free software; you can redistribute it and/or modify it under
   8 % the terms of the GNU General Public License as published by the Free
   9 % Software Foundation; either version 2 of the License, or (at your
  10 % option) any later version.
  11 %
  12 % LuaTeX is distributed in the hope that it will be useful, but WITHOUT
  13 % ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 % FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
  15 % License for more details.
  16 %
  17 % You should have received a copy of the GNU General Public License along
  18 % with LuaTeX; if not, see <http://www.gnu.org/licenses/>.
  19
  20 @ @c
  21
  22
  23 #include "ptexlib.h"
  24 #include "lua/luatex-api.h"
  25
  26 @ a bit more interfacing is needed for proper error reporting
  27
  28 @c
  29 static char *font_error_message(pointer u, char *nom, scaled s)
  30 {
  31     char *str = xmalloc(256);
  32     char *c = makecstring(cs_text(u));
  33     const char *extra = "metric data not found or bad";
  34     if (s >= 0) {
  35         snprintf(str, 255, "Font \\%s=%s at %gpt not loadable: %s", c, nom,
  36                  (double) s / 65536, extra);
  37     } else if (s != -1000) {
  38         snprintf(str, 255, "Font \\%s=%s scaled %d not loadable: %s", c, nom,
  39                  (int) (-s), extra);
  40     } else {
  41         snprintf(str, 255, "Font \\%s=%s not loadable: %s", c, nom, extra);
  42     }
  43     free(c);
  44     return str;
  45 }
  46
  47 static int do_define_font(int f, const char *cnom, scaled s, int natural_dir)
  48 {
  49
  50     boolean res;                /* was the callback successful? */
  51     int callback_id;
  52     char *cnam;
  53     int r, t;
  54     res = 0;
  55
  56     callback_id = callback_defined(define_font_callback);
  57     if (callback_id > 0) {
  58         cnam = xstrdup(cnom);
  59         callback_id = run_and_save_callback(callback_id, "Sdd->", cnam, s, f);
  60         free(cnam);
  61         if (callback_id > 0) {  /* success */
  62             luaL_checkstack(Luas, 1, "out of stack space");
  63             lua_rawgeti(Luas, LUA_REGISTRYINDEX, callback_id);
  64             t = lua_type(Luas, -1);
  65             if (t == LUA_TTABLE) {
  66                 res = font_from_lua(Luas, f);
  67                 destroy_saved_callback(callback_id);
  68                 /* |lua_pop(Luas, 1);| *//* done by |font_from_lua| */
  69             } else if (t == LUA_TNUMBER) {
  70                 r = (int) lua_tointeger(Luas, -1);
  71                 destroy_saved_callback(callback_id);
  72                 delete_font(f);
  73                 lua_pop(Luas, 1);
  74                 return r;
  75             } else {
  76                 lua_pop(Luas, 1);
  77                 delete_font(f);
  78                 return 0;
  79             }
  80         }
  81     } else if (callback_id == 0) {
  82         res = read_tfm_info(f, cnom, s);
  83         if (res) {
  84             set_hyphen_char(f, int_par(default_hyphen_char_code));
  85             set_skew_char(f, int_par(default_skew_char_code));
  86         }
  87     }
  88     if (font_name(f) && strlen(font_name(f)) > 255) {
  89         /* the font name has to fit in the dvi file's single byte storage */
  90         /* no need to test area, as we are never using it */
  91         res = 0;
  92     }
  93     if (res) {
  94         if (font_type(f) != virtual_font_type) {        /* implies lua */
  95             do_vf(f);
  96             set_font_natural_dir(f, natural_dir);
  97         }
  98         return f;
  99     } else {
 100         delete_font(f);
 101         return 0;
 102     }
 103
 104 }
 105
 106 int read_font_info(pointer u, char *cnom, scaled s, int natural_dir)
 107 {
 108     int f;
 109     char *msg;
 110
 111     f = new_font();
 112     if ((f = do_define_font(f, cnom, s, natural_dir))) {
 113         return f;
 114     } else {
 115         const char *help[] =
 116             { "I wasn't able to read the size data for this font,",
 117             "so I will ignore the font specification.",
 118             "[Wizards can fix TFM files using TFtoPL/PLtoTF.]",
 119             "You might try inserting a different font spec;",
 120             "e.g., type `I\\font<same font id>=<substitute font name>'.",
 121             NULL
 122         };
 123         if (int_par(suppress_fontnotfound_error_code) == 0) {
 124             msg = font_error_message(u, cnom, s);
 125             tex_error(msg, help);
 126             free(msg);
 127         }
 128         return 0;
 129     }
 130 }
 131
 132 @ TODO This function is a placeholder. There can easily appears holes in
 133    the |font_tables| array, and we could attempt to reuse those
 134
 135 @c
 136 int find_font_id(const char *nom, scaled s)
 137 {
 138     int f;
 139     f = new_font();
 140     if ((f = do_define_font(f, nom, s, -1))) {
 141         return f;
 142     } else {
 143         return 0;
 144     }
 145 }