termcap.c

   1 /*@ S-nail - a mail user agent derived from Berkeley Mail.
   2  *@ Terminal capability interaction. TODO very rudimentary yet
   3  *
   4  * Copyright (c) 2015 Steffen (Daode) Nurpmeso <sdaoden@users.sf.net>.
   5  *
   6  * Permission to use, copy, modify, and/or distribute this software for any
   7  * purpose with or without fee is hereby granted, provided that the above
   8  * copyright notice and this permission notice appear in all copies.
   9  *
  10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
  13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  17  */
  18 #undef n_FILE
  19 #define n_FILE termcap
  20
  21 #ifndef HAVE_AMALGAMATION
  22 # include "nail.h"
  23 #endif
  24
  25 EMPTY_FILE()
  26 #ifdef HAVE_TERMCAP
  27 /* If available, curses.h must be included before term.h! */
  28 #ifdef HAVE_TERMCAP_CURSES
  29 # include <curses.h>
  30 #endif
  31
  32 #include <term.h>
  33
  34 static char    *_termcap_buffer, *_termcap_ti, *_termcap_te;
  35
  36 static int     _termcap_putc(int c);
  37
  38 static int
  39 _termcap_putc(int c)
  40 {
  41    return putchar(c);
  42 }
  43
  44 FL void
  45 termcap_init(void)
  46 {
  47    /* For newer ncurses based termcap emulation buf will remain unused, for
  48     * elder non-emulated ones really weird things will happen if an entry
  49     * would require more than 1024 bytes, so don't mind.
  50     * Things are more unserious with cmdbuf, but a single termcap command
  51     * should really not excess that limit */
  52    char buf[1024 + 512], cmdbuf[2048], *cpb, *cpti, *cpte, *cp;
  53    NYD_ENTER;
  54
  55    /* We don't do nothing unless stdout is a terminal TODO */
  56    if (!(options & OPT_TTYOUT))
  57       goto jleave;
  58
  59    if (!ok_blook(term_ca_mode))
  60       goto jleave;
  61    if ((cp = env_vlook("TERM", FAL0)) == NULL)
  62       goto jleave;
  63
  64    if (!tgetent(buf, cp))
  65       goto jleave;
  66    cpb = cmdbuf;
  67
  68    cpti = cpb;
  69    if ((cp = tgetstr(UNCONST("ti"), &cpb)) == NULL)
  70       goto jleave;
  71    cpte = cpb;
  72    if ((cp = tgetstr(UNCONST("te"), &cpb)) == NULL)
  73       goto jleave;
  74
  75    _termcap_buffer = smalloc(PTR2SIZE(cpb - cmdbuf));
  76    memcpy(_termcap_buffer, cmdbuf, PTR2SIZE(cpb - cmdbuf));
  77
  78    _termcap_ti = _termcap_buffer + PTR2SIZE(cpti - cmdbuf);
  79    _termcap_te = _termcap_ti + PTR2SIZE(cpte - cpti);
  80
  81    tputs(_termcap_ti, 1, &_termcap_putc);
  82    fflush(stdout);
  83 jleave:
  84    NYD_LEAVE;
  85 }
  86
  87 FL void
  88 termcap_destroy(void)
  89 {
  90    NYD_ENTER;
  91
  92    if (_termcap_buffer == NULL)
  93       goto jleave;
  94
  95    tputs(_termcap_te, 1, &_termcap_putc);
  96
  97    free(_termcap_buffer);
  98 jleave:
  99    NYD_LEAVE;
 100 }
 101
 102 #endif /* HAVE_TERMCAP */
 103
 104 /* s-it-mode */