root/lib/libcurses/base/lib_newterm.c
/* $OpenBSD: lib_newterm.c,v 1.14 2023/10/17 09:52:08 nicm Exp $ */

/****************************************************************************
 * Copyright 2018-2020,2022 Thomas E. Dickey                                *
 * Copyright 1998-2016,2017 Free Software Foundation, Inc.                  *
 *                                                                          *
 * Permission is hereby granted, free of charge, to any person obtaining a  *
 * copy of this software and associated documentation files (the            *
 * "Software"), to deal in the Software without restriction, including      *
 * without limitation the rights to use, copy, modify, merge, publish,      *
 * distribute, distribute with modifications, sublicense, and/or sell       *
 * copies of the Software, and to permit persons to whom the Software is    *
 * furnished to do so, subject to the following conditions:                 *
 *                                                                          *
 * The above copyright notice and this permission notice shall be included  *
 * in all copies or substantial portions of the Software.                   *
 *                                                                          *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS  *
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF               *
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.   *
 * IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,   *
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR    *
 * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR    *
 * THE USE OR OTHER DEALINGS IN THE SOFTWARE.                               *
 *                                                                          *
 * Except as contained in this notice, the name(s) of the above copyright   *
 * holders shall not be used in advertising or otherwise to promote the     *
 * sale, use or other dealings in this Software without prior written       *
 * authorization.                                                           *
 ****************************************************************************/

/****************************************************************************
 *  Author: Zeyd M. Ben-Halim <zmbenhal@netcom.com> 1992,1995               *
 *     and: Eric S. Raymond <esr@snark.thyrsus.com>                         *
 *     and: Thomas E. Dickey                        1996-on                 *
 *     and: Juergen Pfeifer                         2009                    *
 ****************************************************************************/

/*
**      lib_newterm.c
**
**      The newterm() function.
**
*/

#include <curses.priv.h>

#ifndef CUR
#define CUR SP_TERMTYPE
#endif

#include <tic.h>

MODULE_ID("$Id: lib_newterm.c,v 1.14 2023/10/17 09:52:08 nicm Exp $")

#ifdef USE_TERM_DRIVER
#define NumLabels      InfoOf(SP_PARM).numlabels
#else
#define NumLabels      num_labels
#endif

#ifndef ONLCR                   /* Allows compilation under the QNX 4.2 OS */
#define ONLCR 0
#endif

/*
 * SVr4/XSI Curses specify that hardware echo is turned off in initscr, and not
 * restored during the curses session.  The library simulates echo in software.
 * (The behavior is unspecified if the application enables hardware echo).
 *
 * The newterm function also initializes terminal settings, and since initscr
 * is supposed to behave as if it calls newterm, we do it here.
 */
static NCURSES_INLINE int
_nc_initscr(NCURSES_SP_DCL0)
{
    int result = ERR;
    TERMINAL *term = TerminalOf(SP_PARM);

    /* for extended XPG4 conformance requires cbreak() at this point */
    /* (SVr4 curses does this anyway) */
    T((T_CALLED("_nc_initscr(%p) ->term %p"), (void *) SP_PARM, (void *) term));
    if (NCURSES_SP_NAME(cbreak) (NCURSES_SP_ARG) == OK) {
        TTY buf;

        buf = term->Nttyb;
#ifdef TERMIOS
        buf.c_lflag &= (unsigned) ~(ECHO | ECHONL);
        buf.c_iflag &= (unsigned) ~(ICRNL | INLCR | IGNCR);
        buf.c_oflag &= (unsigned) ~(ONLCR);
#elif HAVE_SGTTY_H
        buf.sg_flags &= ~(ECHO | CRMOD);
#elif defined(EXP_WIN32_DRIVER)
        buf.dwFlagIn = CONMODE_IN_DEFAULT;
        buf.dwFlagOut = CONMODE_OUT_DEFAULT | VT_FLAG_OUT;
        if (WINCONSOLE.isTermInfoConsole) {
            buf.dwFlagIn |= VT_FLAG_IN;
        }
#else
        memset(&buf, 0, sizeof(buf));
#endif
        result = NCURSES_SP_NAME(_nc_set_tty_mode) (NCURSES_SP_ARGx &buf);
        if (result == OK)
            term->Nttyb = buf;
    }
    returnCode(result);
}

/*
 * filter() has to be called before either initscr() or newterm(), so there is
 * apparently no way to make this flag apply to some terminals and not others,
 * aside from possibly delaying a filter() call until some terminals have been
 * initialized.
 */
NCURSES_EXPORT(void)
NCURSES_SP_NAME(filter) (NCURSES_SP_DCL0)
{
    START_TRACE();
    T((T_CALLED("filter(%p)"), (void *) SP_PARM));
#if NCURSES_SP_FUNCS
    if (IsPreScreen(SP_PARM)) {
        SP_PARM->_filtered = TRUE;
    }
#else
    _nc_prescreen.filter_mode = TRUE;
#endif
    returnVoid;
}

#if NCURSES_SP_FUNCS
NCURSES_EXPORT(void)
filter(void)
{
    START_TRACE();
    T((T_CALLED("filter()")));
    _nc_prescreen.filter_mode = TRUE;
    returnVoid;
}
#endif

#if NCURSES_EXT_FUNCS
/*
 * An extension, allowing the application to open a new screen without
 * requiring it to also be filtered.
 */
NCURSES_EXPORT(void)
NCURSES_SP_NAME(nofilter) (NCURSES_SP_DCL0)
{
    START_TRACE();
    T((T_CALLED("nofilter(%p)"), (void *) SP_PARM));
#if NCURSES_SP_FUNCS
    if (IsPreScreen(SP_PARM)) {
        SP_PARM->_filtered = FALSE;
    }
#else
    _nc_prescreen.filter_mode = FALSE;
#endif
    returnVoid;
}

#if NCURSES_SP_FUNCS
NCURSES_EXPORT(void)
nofilter(void)
{
    START_TRACE();
    T((T_CALLED("nofilter()")));
    _nc_prescreen.filter_mode = FALSE;
    returnVoid;
}
#endif
#endif /* NCURSES_EXT_FUNCS */

NCURSES_EXPORT(SCREEN *)
NCURSES_SP_NAME(newterm) (NCURSES_SP_DCLx
                          const char *name,
                          FILE *ofp,
                          FILE *ifp)
{
    int errret;
    SCREEN *result = 0;
    SCREEN *current;
    TERMINAL *its_term;
    FILE *_ofp = ofp ? ofp : stdout;
    FILE *_ifp = ifp ? ifp : stdin;
    TERMINAL *new_term = 0;

    START_TRACE();
    T((T_CALLED("newterm(%p, \"%s\", %p,%p)"),
       (void *) SP_PARM,
       (name ? name : ""),
       (void *) ofp,
       (void *) ifp));

#if NCURSES_SP_FUNCS
    assert(SP_PARM != 0);
    if (SP_PARM == 0)
        returnSP(SP_PARM);
#endif

    _nc_init_pthreads();
    _nc_lock_global(curses);

    current = CURRENT_SCREEN;
    its_term = (current ? current->_term : 0);

#if defined(EXP_WIN32_DRIVER)
    _setmode(fileno(_ifp), _O_BINARY);
    _setmode(fileno(_ofp), _O_BINARY);
#endif

    INIT_TERM_DRIVER();
    /* this loads the capability entry, then sets LINES and COLS */
    if (
           TINFO_SETUP_TERM(&new_term, name,
                            fileno(_ofp), &errret, FALSE) != ERR) {
        int slk_format;
        int filter_mode;

        _nc_set_screen(0);
#ifdef USE_TERM_DRIVER
        assert(new_term != 0);
#endif

#if NCURSES_SP_FUNCS
        slk_format = SP_PARM->slk_format;
        filter_mode = SP_PARM->_filtered;
#else
        slk_format = _nc_globals.slk_format;
        filter_mode = _nc_prescreen.filter_mode;
#endif

        /*
         * This actually allocates the screen structure, and saves the original
         * terminal settings.
         */
        if (NCURSES_SP_NAME(_nc_setupscreen) (
#if NCURSES_SP_FUNCS
                                                 &SP_PARM,
#endif
                                                 *(ptrLines(SP_PARM)),
                                                 *(ptrCols(SP_PARM)),
                                                 _ofp,
                                                 filter_mode,
                                                 slk_format) == ERR) {
            _nc_set_screen(current);
            result = 0;
        } else {
            int value;
            int cols;

#ifdef USE_TERM_DRIVER
            TERMINAL_CONTROL_BLOCK *TCB;
#elif !NCURSES_SP_FUNCS
            _nc_set_screen(CURRENT_SCREEN);
#endif
            assert(SP_PARM != 0);
            cols = *(ptrCols(SP_PARM));
#ifdef USE_TERM_DRIVER
            _nc_set_screen(SP_PARM);
            TCB = (TERMINAL_CONTROL_BLOCK *) new_term;
            TCB->csp = SP_PARM;
#endif
            /*
             * In setupterm() we did a set_curterm(), but it was before we set
             * CURRENT_SCREEN.  So the "current" screen's terminal pointer was
             * overwritten with a different terminal.  Later, in
             * _nc_setupscreen(), we set CURRENT_SCREEN and the terminal
             * pointer in the new screen.
             *
             * Restore the terminal-pointer for the pre-existing screen, if
             * any.
             */
            if (current)
                current->_term = its_term;

#ifdef USE_TERM_DRIVER
            SP_PARM->_term = new_term;
#else
            new_term = SP_PARM->_term;
#endif

            /* allow user to set maximum escape delay from the environment */
            if ((value = _nc_getenv_num("ESCDELAY")) >= 0) {
#if NCURSES_EXT_FUNCS
                NCURSES_SP_NAME(set_escdelay) (NCURSES_SP_ARGx value);
#else
                ESCDELAY = value;
#endif
            }

            /* if the terminal type has real soft labels, set those up */
            if (slk_format && NumLabels > 0 && SLK_STDFMT(slk_format))
                _nc_slk_initialize(StdScreen(SP_PARM), cols);

            SP_PARM->_ifd = fileno(_ifp);
            NCURSES_SP_NAME(typeahead) (NCURSES_SP_ARGx fileno(_ifp));
#ifdef TERMIOS
            SP_PARM->_use_meta = ((new_term->Ottyb.c_cflag & CSIZE) == CS8 &&
                                  !(new_term->Ottyb.c_iflag & ISTRIP)) ||
                USE_KLIBC_KBD;
#else
            SP_PARM->_use_meta = FALSE;
#endif
            SP_PARM->_endwin = ewInitial;
#ifndef USE_TERM_DRIVER
            /*
             * Check whether we can optimize scrolling under dumb terminals in
             * case we do not have any of these capabilities, scrolling
             * optimization will be useless.
             */
            SP_PARM->_scrolling = ((scroll_forward && scroll_reverse) ||
                                   ((parm_rindex ||
                                     parm_insert_line ||
                                     insert_line) &&
                                    (parm_index ||
                                     parm_delete_line ||
                                     delete_line)));
#endif

            NCURSES_SP_NAME(baudrate) (NCURSES_SP_ARG);         /* sets a field in the screen structure */

            SP_PARM->_keytry = 0;

            /* compute movement costs so we can do better move optimization */
#ifdef USE_TERM_DRIVER
            TCBOf(SP_PARM)->drv->td_scinit(SP_PARM);
#else /* ! USE_TERM_DRIVER */
            /*
             * Check for mismatched graphic-rendition capabilities.  Most SVr4
             * terminfo trees contain entries that have rmul or rmso equated to
             * sgr0 (Solaris curses copes with those entries).  We do this only
             * for curses, since many termcap applications assume that
             * smso/rmso and smul/rmul are paired, and will not function
             * properly if we remove rmso or rmul.  Curses applications
             * shouldn't be looking at this detail.
             */
#define SGR0_TEST(mode) (mode != 0) && (exit_attribute_mode == 0 || strcmp(mode, exit_attribute_mode))
            SP_PARM->_use_rmso = SGR0_TEST(exit_standout_mode);
            SP_PARM->_use_rmul = SGR0_TEST(exit_underline_mode);
#if USE_ITALIC
            SP_PARM->_use_ritm = SGR0_TEST(exit_italics_mode);
#endif

            /* compute movement costs so we can do better move optimization */
            _nc_mvcur_init();

            /* initialize terminal to a sane state */
            _nc_screen_init();
#endif /* USE_TERM_DRIVER */

            /* Initialize the terminal line settings. */
            _nc_initscr(NCURSES_SP_ARG);

            _nc_signal_handler(TRUE);
            result = SP_PARM;
        }
    }
    _nc_unlock_global(curses);
    returnSP(result);
}

#if NCURSES_SP_FUNCS
NCURSES_EXPORT(SCREEN *)
newterm(const char *name, FILE *ofp, FILE *ifp)
{
    SCREEN *rc;

    _nc_init_pthreads();
    _nc_lock_global(prescreen);
    START_TRACE();
    rc = NCURSES_SP_NAME(newterm) (CURRENT_SCREEN_PRE, name, ofp, ifp);
    _nc_forget_prescr();
    _nc_unlock_global(prescreen);

    return rc;
}
#endif