lib_setup.c

ncurses 库 可能有用酒用 没用就算了 我觉得还可以用

	 * real terminfo database and use that.
	 */
	status = _nc_read_termcap_entry(tn, tp);
#endif /* PURE_TERMINFO */

    }
#else
    status = _nc_read_termcap_entry(tn, tp);
#endif

    /*
     * If we have an entry, force all of the cancelled strings to null
     * pointers so we don't have to test them in the rest of the library.
     * (The terminfo compiler bypasses this logic, since it must know if
     * a string is cancelled, for merging entries).
     */
    if (status == 1) {
	unsigned n;
	for_each_boolean(n, tp) {
	    if (!VALID_BOOLEAN(tp->Booleans[n]))
		tp->Booleans[n] = FALSE;
	}
	for_each_string(n, tp) {
	    if (tp->Strings[n] == CANCELLED_STRING)
		tp->Strings[n] = ABSENT_STRING;
	}
    }
    return (status);
}
#endif

/*
**	do_prototype()
**
**	Take the real command character out of the CC environment variable
**	and substitute it in for the prototype given in 'command_character'.
**
*/
static void
do_prototype(void)
{
    int i;
    char CC;
    char proto;
    char *tmp;

    tmp = getenv("CC");
    CC = *tmp;
    proto = *command_character;

    for_each_string(i, &(cur_term->type)) {
	for (tmp = cur_term->type.Strings[i]; *tmp; tmp++) {
	    if (*tmp == proto)
		*tmp = CC;
	}
    }
}

/*
 * Find the locale which is in effect.
 */
NCURSES_EXPORT(char *)
_nc_get_locale(void)
{
    char *env;
#if HAVE_LOCALE_H
    /*
     * This is preferable to using getenv() since it ensures that we are using
     * the locale which was actually initialized by the application.
     */
    env = setlocale(LC_CTYPE, 0);
#else
    if (((env = getenv("LC_ALL")) != 0 && *env != '\0')
	|| ((env = getenv("LC_CTYPE")) != 0 && *env != '\0')
	|| ((env = getenv("LANG")) != 0 && *env != '\0')) {
	;
    }
#endif
    T(("_nc_get_locale %s", _nc_visbuf(env)));
    return env;
}

/*
 * Check if we are running in a UTF-8 locale.
 */
NCURSES_EXPORT(int)
_nc_unicode_locale(void)
{
    int result = 0;
#if HAVE_LANGINFO_CODESET
    char *env = nl_langinfo(CODESET);
    result = !strcmp(env, "UTF-8");
    T(("_nc_unicode_locale(%s) ->%d", env, result));
#else
    char *env = _nc_get_locale();
    if (env != 0) {
	if (strstr(env, ".UTF-8") != 0) {
	    result = 1;
	    T(("_nc_unicode_locale(%s) ->%d", env, result));
	}
    }
#endif
    return result;
}

#define CONTROL_N(s) ((s) != 0 && strstr(s, "\016") != 0)
#define CONTROL_O(s) ((s) != 0 && strstr(s, "\017") != 0)

/*
 * Check for known broken cases where a UTF-8 locale breaks the alternate
 * character set.
 */
NCURSES_EXPORT(int)
_nc_locale_breaks_acs(void)
{
    char *env;

    if ((env = getenv("NCURSES_NO_UTF8_ACS")) != 0) {
	return atoi(env);
    } else if ((env = getenv("TERM")) != 0) {
	if (strstr(env, "linux"))
	    return 1;		/* always broken */
	if (strstr(env, "screen") != 0
	    && ((env = getenv("TERMCAP")) != 0
		&& strstr(env, "screen") != 0)
	    && strstr(env, "hhII00") != 0) {
	    if (CONTROL_N(enter_alt_charset_mode) ||
		CONTROL_O(enter_alt_charset_mode) ||
		CONTROL_N(set_attributes) ||
		CONTROL_O(set_attributes))
		return 1;
	}
    }
    return 0;
}

/*
 * This entrypoint is called from tgetent() to allow special a case of reusing
 * the same TERMINAL data (see comment).
 */
NCURSES_EXPORT(int)
_nc_setupterm(NCURSES_CONST char *tname, int Filedes, int *errret, bool reuse)
{
    int status;

    START_TRACE();
    T((T_CALLED("setupterm(%s,%d,%p)"), _nc_visbuf(tname), Filedes, errret));

    if (tname == 0) {
	tname = getenv("TERM");
	if (tname == 0 || *tname == '\0') {
	    ret_error0(-1, "TERM environment variable not set.\n");
	}
    }
    if (strlen(tname) > MAX_NAME_SIZE) {
	ret_error(-1, "TERM environment must be <= %d characters.\n",
		  MAX_NAME_SIZE);
    }

    T(("your terminal name is %s", tname));

    /*
     * Allow output redirection.  This is what SVr3 does.  If stdout is
     * directed to a file, screen updates go to standard error.
     */
    if (Filedes == STDOUT_FILENO && !isatty(Filedes))
	Filedes = STDERR_FILENO;

    /*
     * Check if we have already initialized to use this terminal.  If so, we
     * do not need to re-read the terminfo entry, or obtain TTY settings.
     *
     * This is an improvement on SVr4 curses.  If an application mixes curses
     * and termcap calls, it may call both initscr and tgetent.  This is not
     * really a good thing to do, but can happen if someone tries using ncurses
     * with the readline library.  The problem we are fixing is that when
     * tgetent calls setupterm, the resulting Ottyb struct in cur_term is
     * zeroed.  A subsequent call to endwin uses the zeroed terminal settings
     * rather than the ones saved in initscr.  So we check if cur_term appears
     * to contain terminal settings for the same output file as our current
     * call - and copy those terminal settings.  (SVr4 curses does not do this,
     * however applications that are working around the problem will still work
     * properly with this feature).
     */
    if (reuse
	&& cur_term != 0
	&& cur_term->Filedes == Filedes
	&& cur_term->_termname != 0
	&& !strcmp(cur_term->_termname, tname)
	&& _nc_name_match(cur_term->type.term_names, tname, "|")) {
	T(("reusing existing terminal information and mode-settings"));
    } else {
	TERMINAL *term_ptr;

	term_ptr = typeCalloc(TERMINAL, 1);

	if (term_ptr == 0) {
	    ret_error0(-1,
		       "Not enough memory to create terminal structure.\n");
	}
#if USE_DATABASE || USE_TERMCAP
	status = grab_entry(tname, &term_ptr->type);
#else
	status = 0;
#endif

	/* try fallback list if entry on disk */
	if (status != 1) {
	    const TERMTYPE *fallback = _nc_fallback(tname);

	    if (fallback) {
		term_ptr->type = *fallback;
		status = 1;
	    }
	}

	if (status <= 0) {
	    del_curterm(term_ptr);
	    if (status == -1) {
		ret_error0(-1, "terminals database is inaccessible\n");
	    } else if (status == 0) {
		ret_error(0, "'%s': unknown terminal type.\n", tname);
	    }
	}

	set_curterm(term_ptr);

	if (command_character && getenv("CC"))
	    do_prototype();

	strncpy(ttytype, cur_term->type.term_names, NAMESIZE - 1);
	ttytype[NAMESIZE - 1] = '\0';

	cur_term->Filedes = Filedes;
	cur_term->_termname = strdup(tname);

	/*
	 * If an application calls setupterm() rather than initscr() or
	 * newterm(), we will not have the def_prog_mode() call in
	 * _nc_setupscreen().  Do it now anyway, so we can initialize the
	 * baudrate.
	 */
	if (isatty(Filedes)) {
	    def_prog_mode();
	    baudrate();
	}
    }

    /*
     * We should always check the screensize, just in case.
     */
    _nc_get_screensize(&LINES, &COLS);

    if (errret)
	*errret = 1;

    T((T_CREATE("screen %s %dx%d"), tname, LINES, COLS));

    if (generic_type) {
	ret_error(0, "'%s': I need something more specific.\n", tname);
    }
    if (hard_copy) {
	ret_error(1, "'%s': I can't handle hardcopy terminals.\n", tname);
    }
    returnCode(OK);
}

/*
 *	setupterm(termname, Filedes, errret)
 *
 *	Find and read the appropriate object file for the terminal
 *	Make cur_term point to the structure.
 *
 */

NCURSES_EXPORT(int)
setupterm(NCURSES_CONST char *tname, int Filedes, int *errret)
{
    return _nc_setupterm(tname, Filedes, errret, FALSE);
}