src/viewer/nroff.c

   1 /*
   2    Internal file viewer for the Midnight Commander
   3    Functions for searching in nroff-like view
   4
   5    Copyright (C) 1994-2016
   6    Free Software Foundation, Inc.
   7
   8    Written by:
   9    Miguel de Icaza, 1994, 1995, 1998
  10    Janne Kukonlehto, 1994, 1995
  11    Jakub Jelinek, 1995
  12    Joseph M. Hinkle, 1996
  13    Norbert Warmuth, 1997
  14    Pavel Machek, 1998
  15    Roland Illig <roland.illig@gmx.de>, 2004, 2005
  16    Slava Zanko <slavazanko@google.com>, 2009
  17    Andrew Borodin <aborodin@vmail.ru>, 2009
  18    Ilia Maslakov <il.smind@gmail.com>, 2009
  19
  20    This file is part of the Midnight Commander.
  21
  22    The Midnight Commander is free software: you can redistribute it
  23    and/or modify it under the terms of the GNU General Public License as
  24    published by the Free Software Foundation, either version 3 of the License,
  25    or (at your option) any later version.
  26
  27    The Midnight Commander is distributed in the hope that it will be useful,
  28    but WITHOUT ANY WARRANTY; without even the implied warranty of
  29    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  30    GNU General Public License for more details.
  31
  32    You should have received a copy of the GNU General Public License
  33    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  34  */
  35
  36 #include <config.h>
  37
  38 #include "lib/global.h"
  39 #include "lib/tty/tty.h"
  40 #include "lib/skin.h"
  41 #ifdef HAVE_CHARSET
  42 #include "lib/charsets.h"
  43 #endif
  44
  45 #include "src/setup.h"          /* option_tab_spacing */
  46
  47 #include "internal.h"
  48
  49 /*** global variables ****************************************************************************/
  50
  51 /*** file scope macro definitions ****************************************************************/
  52
  53 /*** file scope type declarations ****************************************************************/
  54
  55 /*** file scope variables ************************************************************************/
  56
  57 /*** file scope functions ************************************************************************/
  58 /* --------------------------------------------------------------------------------------------- */
  59
  60 static gboolean
  61 mcview_nroff_get_char (mcview_nroff_t * nroff, int *ret_val, off_t nroff_index)
  62 {
  63     int c = 0;
  64
  65 #ifdef HAVE_CHARSET
  66     if (nroff->view->utf8)
  67     {
  68         if (!mcview_get_utf (nroff->view, nroff_index, &c, &nroff->char_length))
  69         {
  70             /* we need got symbol in any case */
  71             nroff->char_length = 1;
  72             if (!mcview_get_byte (nroff->view, nroff_index, &c) || !g_ascii_isprint (c))
  73                 return FALSE;
  74         }
  75     }
  76     else
  77 #endif
  78     {
  79         nroff->char_length = 1;
  80         if (!mcview_get_byte (nroff->view, nroff_index, &c))
  81             return FALSE;
  82     }
  83
  84     *ret_val = c;
  85
  86     return g_unichar_isprint (c);
  87 }
  88
  89 /* --------------------------------------------------------------------------------------------- */
  90 /*** public functions ****************************************************************************/
  91 /* --------------------------------------------------------------------------------------------- */
  92
  93 int
  94 mcview__get_nroff_real_len (WView * view, off_t start, off_t length)
  95 {
  96     mcview_nroff_t *nroff;
  97     int ret = 0;
  98     off_t i = 0;
  99
 100     if (!view->text_nroff_mode)
 101         return 0;
 102
 103     nroff = mcview_nroff_seq_new_num (view, start);
 104     if (nroff == NULL)
 105         return 0;
 106     while (i < length)
 107     {
 108         switch (nroff->type)
 109         {
 110         case NROFF_TYPE_BOLD:
 111             ret += 1 + nroff->char_length;      /* real char length and 0x8 */
 112             break;
 113         case NROFF_TYPE_UNDERLINE:
 114             ret += 2;           /* underline symbol and ox8 */
 115             break;
 116         default:
 117             break;
 118         }
 119         i += nroff->char_length;
 120         mcview_nroff_seq_next (nroff);
 121     }
 122
 123     mcview_nroff_seq_free (&nroff);
 124     return ret;
 125 }
 126
 127 /* --------------------------------------------------------------------------------------------- */
 128
 129 mcview_nroff_t *
 130 mcview_nroff_seq_new_num (WView * view, off_t lc_index)
 131 {
 132     mcview_nroff_t *nroff;
 133
 134     nroff = g_try_malloc0 (sizeof (mcview_nroff_t));
 135     if (nroff != NULL)
 136     {
 137         nroff->index = lc_index;
 138         nroff->view = view;
 139         mcview_nroff_seq_info (nroff);
 140     }
 141     return nroff;
 142 }
 143
 144 /* --------------------------------------------------------------------------------------------- */
 145
 146 mcview_nroff_t *
 147 mcview_nroff_seq_new (WView * view)
 148 {
 149     return mcview_nroff_seq_new_num (view, (off_t) 0);
 150
 151 }
 152
 153 /* --------------------------------------------------------------------------------------------- */
 154
 155 void
 156 mcview_nroff_seq_free (mcview_nroff_t ** nroff)
 157 {
 158     if (nroff == NULL || *nroff == NULL)
 159         return;
 160     MC_PTR_FREE (*nroff);
 161 }
 162
 163 /* --------------------------------------------------------------------------------------------- */
 164
 165 nroff_type_t
 166 mcview_nroff_seq_info (mcview_nroff_t * nroff)
 167 {
 168     int next, next2;
 169
 170     if (nroff == NULL)
 171         return NROFF_TYPE_NONE;
 172     nroff->type = NROFF_TYPE_NONE;
 173
 174     if (!mcview_nroff_get_char (nroff, &nroff->current_char, nroff->index))
 175         return nroff->type;
 176
 177     if (!mcview_get_byte (nroff->view, nroff->index + nroff->char_length, &next) || next != '\b')
 178         return nroff->type;
 179
 180     if (!mcview_nroff_get_char (nroff, &next2, nroff->index + 1 + nroff->char_length))
 181         return nroff->type;
 182
 183     if (nroff->current_char == '_' && next2 == '_')
 184     {
 185         nroff->type = (nroff->prev_type == NROFF_TYPE_BOLD)
 186             ? NROFF_TYPE_BOLD : NROFF_TYPE_UNDERLINE;
 187
 188     }
 189     else if (nroff->current_char == next2)
 190     {
 191         nroff->type = NROFF_TYPE_BOLD;
 192     }
 193     else if (nroff->current_char == '_')
 194     {
 195         nroff->current_char = next2;
 196         nroff->type = NROFF_TYPE_UNDERLINE;
 197     }
 198     else if (nroff->current_char == '+' && next2 == 'o')
 199     {
 200         /* ??? */
 201     }
 202     return nroff->type;
 203 }
 204
 205 /* --------------------------------------------------------------------------------------------- */
 206
 207 int
 208 mcview_nroff_seq_next (mcview_nroff_t * nroff)
 209 {
 210     if (nroff == NULL)
 211         return -1;
 212
 213     nroff->prev_type = nroff->type;
 214
 215     switch (nroff->type)
 216     {
 217     case NROFF_TYPE_BOLD:
 218         nroff->index += 1 + nroff->char_length;
 219         break;
 220     case NROFF_TYPE_UNDERLINE:
 221         nroff->index += 2;
 222         break;
 223     default:
 224         break;
 225     }
 226
 227     nroff->index += nroff->char_length;
 228
 229     mcview_nroff_seq_info (nroff);
 230     return nroff->current_char;
 231 }
 232
 233 /* --------------------------------------------------------------------------------------------- */
 234
 235 int
 236 mcview_nroff_seq_prev (mcview_nroff_t * nroff)
 237 {
 238     int prev;
 239     off_t prev_index, prev_index2;
 240
 241     if (nroff == NULL)
 242         return -1;
 243
 244     nroff->prev_type = NROFF_TYPE_NONE;
 245
 246     if (nroff->index == 0)
 247         return -1;
 248
 249     prev_index = nroff->index - 1;
 250
 251     while (prev_index != 0)
 252     {
 253         if (mcview_nroff_get_char (nroff, &nroff->current_char, prev_index))
 254             break;
 255         prev_index--;
 256     }
 257     if (prev_index == 0)
 258     {
 259         nroff->index--;
 260         mcview_nroff_seq_info (nroff);
 261         return nroff->current_char;
 262     }
 263
 264     prev_index--;
 265
 266     if (!mcview_get_byte (nroff->view, prev_index, &prev) || prev != '\b')
 267     {
 268         nroff->index = prev_index;
 269         mcview_nroff_seq_info (nroff);
 270         return nroff->current_char;
 271     }
 272     prev_index2 = prev_index - 1;
 273
 274     while (prev_index2 != 0)
 275     {
 276         if (mcview_nroff_get_char (nroff, &prev, prev_index))
 277             break;
 278         prev_index2--;
 279     }
 280
 281     nroff->index = (prev_index2 == 0) ? prev_index : prev_index2;
 282     mcview_nroff_seq_info (nroff);
 283     return nroff->current_char;
 284 }
 285
 286 /* --------------------------------------------------------------------------------------------- */