libcurses/screen/tgetch.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*  Copyright (c) 1988 AT&T */
/*    All Rights Reserved   */

/*
 * University Copyright- Copyright (c) 1982, 1986, 1988
 * The Regents of the University of California
 * All Rights Reserved
 *
 * University Acknowledgment- Portions of this document are derived from
 * software developed by the University of California, Berkeley, and its
 * contributors.
 */

/*LINTLIBRARY*/

#include    "curses_inc.h"
#include    <signal.h>
#include    <unistd.h>
#ifdef  DEBUG
#include    <ctype.h>
#endif  /* DEBUG */

/*
 * Read a key typed from the terminal
 *
 * interpret:   = 0 for single-char key only
 *      = 1 for matching function key and macro patterns.
 *      = 2 same as 1 but no time-out for funckey matching.
 */

static  int _getkey(int, chtype *);
static  int _fpk(void);
static  int _pk(void);

chtype
tgetch(int interpret)
{
    int     i = 0, j, collapse = 1;
#define WAIT3       333
    chtype      inp;
    chtype      *inputQ = cur_term->_input_queue;
    char        *chars_onQ = &(cur_term->_chars_on_queue);

#ifdef  SYSV
    /*
     * Register the fact that getch is being used so
     * that typeahead checking can be done.
     * This code should GO AWAY when a poll() or FIONREAD can
     * be done on the file descriptor as then the check
     * will be non-destructive.
     */
    cur_term->fl_typeahdok = TRUE;
#endif  /* SYSV */

    /* ask for input */
    if (cur_term->_ungotten > 0) {
        cur_term->_ungotten--;
        /* decode an ungetch()'d character */
        inp = -inputQ[0];
    } else {
        /* Only read a character if there is no typeahead/peekahead. */
        if (*chars_onQ == 0) {
            /* (*chars_onQ)++;  MR */
#ifdef  FIONREAD
            inp = _readchar();
#else   /* FIONREAD */
            inp = (chtype) _pk();
            if ((int)inp == ERR) {
        /*
         * interpret is set to 0 so that down below we don't
         * drop into getkey since we already know there can't be
         * a key that starts with -1.  Also, we don't want to
         * access funckeystarter[-1].
         */
                interpret = FALSE;
            }
#endif  /* FIONREAD */
            (*chars_onQ)++;
        } else
            inp = inputQ[0];

#ifdef  DEBUG
        if (outf)
            fprintf(outf, "TGETCH read '%s'\n", unctrl(inp));
#endif  /* DEBUG */

        /* Check for arrow and function keys */
        if (interpret && cur_term->funckeystarter[inp])
            collapse = _getkey(interpret - 1, &inp);
    }

    /* Collapse the input queue to remove the escape */
    /* sequence from the stack. */

    j = *chars_onQ;
    (*chars_onQ) -= collapse;
    while (collapse < j)
        inputQ[i++] = inputQ[collapse++];
    return (inp);
}

#ifdef  FIONREAD
static  int
_readchar()
{
    int     i;
    unsigned    char    c;

    if (cur_term->_delay == 0) {
        int arg;

        (void) ioctl(cur_term->_inputfd, FIONREAD, &arg);
#ifdef  DEBUG
        if (outf)
            fprintf(outf, "FIONREAD returns %d\n", arg);
#endif  /* DEBUG */
        if (arg < 1)
            return (-1);
    } else
        if (cur_term->_delay > 0) {
            char    c;
            int infd;

            infd = 1 << cur_term->_inputfd;
            t.tv_sec = cur_term->_delay / 1000;
            t.tv_usec = (cur_term->_delay % 1000) * 1000;
            i = select(20, &infd, (int *)NULL, (int *)NULL, &t);
            if (i < 0)
                return (ERR);
            i = read(cur_term->_inputfd, &c, 1);
        } else
            i = read(cur_term->_inputfd, &c, 1);

#ifdef  DEBUG
    if (outf)
        fprintf(outf, "read from %d returns %d chars, first %o\n",
            cur_term->_inputfd, i, c);
#endif  /* DEBUG */

    if (i > 0)
        return (c);
    else
        return (ERR);
}
#endif  /* !FIONREAD */

#ifdef  DEBUG
extern  char    *_asciify();
#endif  /* DEBUG */

static int get_xterm_mouse(int, int *);
static void _map_button(chtype *);

/*
 * This algorithm is a "learning" algorithm. The premise is
 * that keys used once are like to be used again and again.
 * Since the time for a linear search of the table is so
 * expensive, we move keys that are found up to the top of
 * the list, making the access to a repeated key very fast and
 * keys that have been used before close to the top.
 */

static  int
_getkey(int blockpeek, chtype *inp)
{
    _KEY_MAP    **kp = cur_term->_keys;
    int     key, num_keys = cur_term->_ksz;
    int     i;
    chtype      *inputQ = cur_term->_input_queue;
    char        *chars_onQ = &(cur_term->_chars_on_queue);
    char        flag = cur_term->funckeystarter[*inp];
    int     first, collapse = 1;


#ifdef  DEBUG
    if (outf)
        fprintf(outf, "getkey(): looking in linear table, "
            "inp=%d\n", *inp);
#endif  /* DEBUG */

    if (flag & _KEY)
        key = 0;
    else {
        key = cur_term->_first_macro;
        blockpeek = TRUE;
    }
    first = key;

    for (; key < num_keys; key++) {
        if (kp[key]->_sends[0] == *inp) {
            for (i = 1; i < INP_QSIZE; i++) {
                /* found it? */
                if (kp[key]->_sends[i] == '\0')
                    break;
                /* partial match? peek ahead. */
                if (*chars_onQ == i) {
                    (*chars_onQ)++;
                    inputQ[i] = (blockpeek) ?
                        _pk() : _fpk();
                    switch ((int)inputQ[i]) {
                    case -2:
            /*
             * Since -2 signifies a timeout we don't really
             * want to put it on the queue so we decrement
             * our counter.
             */
                        (*chars_onQ)--;
#ifdef  DEBUG
                    if (outf)
                        fprintf(outf, "Timed out\n");
#endif  /* DEBUG */
                    if (flag & _MACRO) {
#ifdef  DEBUG
                        if (outf)
                            fprintf(outf,
                                "Found macro\n");
#endif  /* DEBUG */
                /*
                 * We have to decrement one because key will be
                 * incremented at the bottom of the out loop.
                 */
                        key = (first = blockpeek =
                            cur_term->_first_macro) -
                            1;
                        goto outerloop;
                    }

                    /*FALLTHROUGH*/

                    case -1:
                        goto ret;
                    }
                }

                /* not this one? */
                if (kp[key]->_sends[i] != inputQ[i])
                    goto outerloop;
            }

            /* SS-mouse */
            if (kp[key]->_keyval == KEY_MOUSE) {
                MOUSE_STATUS old_mouse;
                int rc;

                old_mouse = Mouse_status;

                /* read the mouse status information    */

                if (mouse_info)
                    rc = -3;    /* NOT IMPLEMENTED */
                else
                    rc = get_xterm_mouse(blockpeek, &i);

                if (rc == -1)       /* read error */
                    goto ret;
                else if (rc == -2 || rc == -3) /* timeout */
                            /* or not mouse */
                    goto outerloop;
                else if (rc == 0) /* report mouse pos */
                    Mouse_status.changes |= 020;
                else if (rc >= 1 && rc <= 3)
                    /* mouse button event */
                    Mouse_status.changes =
                        (((MOUSE_X_POS != old_mouse.x ||
                        MOUSE_Y_POS != old_mouse.y) << 3) |
                        ((Mouse_status.button[2] !=
                        old_mouse.button[2]) << 2) |
                        ((Mouse_status.button[1] !=
                        old_mouse.button[1]) << 1) |
                        (Mouse_status.button[0] !=
                        old_mouse.button[0]));
            }

            /* We found it! Read in any chars left in _sends */

            if ((collapse = i) == INP_QSIZE)
                for (; kp[key]->_sends[i]; i++)
                    (void) _fpk();

            /* move key to top of ordered list */
            if (key != first) {
                _KEY_MAP    *savekey = kp[key];
                short       *lorder;
                int     j;

                if (key > cur_term->_first_macro)
                lorder = &(cur_term->_lastmacro_ordered);
                else
                    lorder = &(cur_term->_lastkey_ordered);
        /*
         * If we're below the last ordered key, swap next unordered
         * key with this one and ripple from there.
         */
                if (key > *lorder)
                    kp[key] = kp[(i = ++(*lorder))];
                else
                    i = key;
                /* ripple the ordered keys down */
                for (j = i--; j > first; )
                    kp[j--] = kp[i--];
                kp[first] = savekey;
            }
            *inp = kp[first]->_keyval;

            /*
             * SS-mouse support: if mouse button event
             * occured on top of the soft label, we may
             * have to return the function key corresponding
             * to that soft label
             */

            if (*inp == KEY_MOUSE && A_BUTTON_CHANGED &&
                (MOUSE_Y_POS == LINES) &&
                (SP->slk != (SLK_MAP *) NULL) &&
                (SP->_map_mbe_to_key  != 0)) {
                _map_button(inp);
            }

            goto ret;
        }
outerloop:
        ;
    }

ret:
    /* key not found */
#ifdef  DEBUG
    if (outf)
        if (key == num_keys)
            fprintf(outf, "Did not match anything.\n");
#endif  /* DEBUG */
    return (collapse);
}


/* SS-mouse */
/* this function tries to read in information that follows KEY_MOUSE: */
/* the first character identifies what button is involved (1,2,or 3)  */
/* if the first character is 0, we are dealing with report_mouse_pos  */
/*
 *  The routine returns the following:
 *      -3: not a mouse button event
 *      -2: read timed out
 *      -1: the read failed
 *      [0, 1, 2, 3] - the first character in the mouse event
 */
static int
get_xterm_mouse(int blockpeek, int *i)
{
    chtype  *inputQ = cur_term->_input_queue;       /* ??? */
    /* LINTED */
    chtype  *chars_onQ = (chtype *) &(cur_term->_chars_on_queue);
    int j, mx, my;
    int char1, char2, c1, c2;

    /* the first character should be 0, 1, 2, or 4  */

    char1 = (inputQ[(*i)++] = (blockpeek) ? _pk() : _fpk());

    /* read error or timeout    */

    if (char1 < 0)
        return (char1);
    (*chars_onQ)++;

    if (char1 < '0' || char1 > '3')
        return (-3);

    /* if the character is 1, 2, or 3 it must be followed by    */
    /* P, R, C, D, or T                     */

    if (char1 != '0') {
        char2 = (inputQ[(*i)++] = (blockpeek) ? _pk() : _fpk());

        if (char2 < 0)
            return (char2);

        (*chars_onQ)++;
        if (char2 != 'P' && char2 != 'R' && char2 != 'C' &&
            char2 != 'D' && char2 != 'T')
            return (-3);
    }

    /* read X  and Y coordinates of the mouse   */

    for (j = 0; j < 2; j++) {
        c1 = (inputQ[(*i)++] = (blockpeek) ? _pk() : _fpk());
        if (c1 < 0)
            return (c1);
        (*chars_onQ)++;
        if (c1 >= ' ' && c1 <= '~') {   /* ascii char */
            if (j == 0)
                mx = c1 - ' ';
            else
                my = c1 - ' ';
        } else if (char1 == 01 || char1 == 02) {   /* ^A || ^B */
            c2 = (inputQ[(*i)++] = (blockpeek) ? _pk() : _fpk());
            if (c2 < 0)
                return (c2);
            (*chars_onQ)++;
            if (c2 >= ' ' && c2 <= '~') {
                if (j == 0)
                    mx = c1 * (c2 - ' ');
                else
                    my = c1 * (c2 - ' ');
            } else
                return (-3);
        } else
            return (-3);
    }

    /* read complete mouse event: update the Mouse_status structure */

    MOUSE_X_POS = mx;
    MOUSE_Y_POS = my;
    j = char1 - '0';
    if (j != 0) {
        switch (char2) {
            case 'P':
                BUTTON_STATUS(j) = BUTTON_PRESSED;
                break;
            case 'R':
                BUTTON_STATUS(j) = BUTTON_RELEASED;
                break;
            case 'C':
                BUTTON_STATUS(j) = BUTTON_CLICKED;
                break;
            case 'D':
                BUTTON_STATUS(j) = BUTTON_DOUBLE_CLICKED;
                break;
            case 'T':
                BUTTON_STATUS(j) = BUTTON_TRIPLE_CLICKED;
                break;
        }
    }
    return (j);
}
/* SS-mouse-end */


/*
 * Fast peek key.  Like getchar but if the right flags are set, times out
 * quickly if there is nothing waiting, returning -1.
 * f is an output stdio descriptor, we read from the fileno.
 * We wait for long enough for a terminal to send another character
 * (at 15cps repeat rate, this is 67 ms, I'm using 100ms to allow
 * a bit of a fudge factor) and time out more quickly.
 * -2 is returned if we time out, -1 is returned if interrupted, and the
 * character is returned otherwise.
 */

#ifndef FIONREAD

/*
 * Traditional implementation.  The best resolution we have is 1 second,
 * so we set a 1 second alarm and try to read.  If we fail for 1 second,
 * we assume there is no key waiting.  Problem here is that 1 second is
 * too long; people can type faster than this.
 *
 * Another possible implementation of changing VMIN/VTIME before and
 * after each read does not work because the tty driver's timeout
 * mechanism is too unreliable when the timeouts are changed too quickly.
 */

static  char    sig_caught;

static
#ifdef  SIGPOLL /* Vr3 and beyond */
void
#endif  /* SIGPOLL */
/* The following line causes a lint warning for "dummy" which is not used. */
_catch_alarm(int dummy)
{
    sig_caught = 1;
}

static int
_fpk(void)
{
    unsigned    char    c;
    int     infd = cur_term->_inputfd;
    ssize_t     rc;
#ifdef  SIGPOLL /* Vr3 and beyond */
    void    (*oldsig)(int);
#else   /* SIGPOLL */
    int     (*oldsig)(int);
#endif  /* SIGPOLL */
    unsigned    int oldalarm, alarm(unsigned);

    /* turn off any user alarms and set our own */
    oldalarm = alarm(0);
    sig_caught = 0;
    oldsig = signal(SIGALRM, _catch_alarm);
    (void) alarm(1);
    rc = read(cur_term->_inputfd, (char *)&c, 1);
    (void) alarm(0);

    /*
     * This code is to take care of the possibility of
     * the process getting swapped out in the middle of
     * read() call above. The interrupt will cause the
     * read() call to retur, even if a character is really
     * on the clist. So we do a non-blocking read() to make
     * sure that there really isn't a character there.
     */

    if (sig_caught && rc != 1)
        if (cur_term->_check_fd != -1)
            rc = read(cur_term->_check_fd, (char *)&c, 1);
        else {
#include    <fcntl.h>
            int fcflags = fcntl(infd, F_GETFL, 0);

            (void) fcntl(infd, F_SETFL, fcflags | O_NDELAY);
            rc = read(infd, (char *)&c, 1);
            (void) fcntl(infd, F_SETFL, fcflags);
        }

    /* restore the user alarms */
    (void) signal(SIGALRM, oldsig);
    if (sig_caught && oldalarm > 1)
        oldalarm--;
    (void) alarm(oldalarm);
    if (rc == 1)            /* got a character */
        return (c);
    else
        if (sig_caught)     /* timed out */
            return (-2);
        else            /* EOF or got interrupted */
            return (-1);
}
#else   /* FIONREAD */
/*
 * If we have the select system call, we can do much better than the
 * traditional method. Even if we don't have the real 4.2BSD select, we
 * can emulate it with napms and FIONREAD.  napms might be done with only
 * 1 second resolution, but this is no worse than what we have in the
 * traditional implementation.
 */
static
_fpk()
{
    int     infd, rc;
    int     *outfd, *exfd;
    unsigned    char    c;
    struct timeval  t;

    infd = 1 << cur_term->_inputfd;
    outfd = exfd = (int *)NULL;
    t.tv_sec = 0;
    t.tv_usec = 100000;     /* 100 milliseconds */
    rc = select(20, &infd, outfd, exfd, &t);
    if (rc < 0)
        return (-2);
    rc = read(fileno(f), &c, 1);
    return (rc == 1 ? c : -1);
}
#endif  /* FIONREAD */

/*
 * Plain peekchar function.  Nothing fancy.  This is just like _fpk
 * but will wait forever rather than time out.
 */

static int
_pk(void)
{
    unsigned    char    c;

    return ((read(cur_term->_inputfd, (char *)&c, 1) == 1) ? c : ERR);
}


/*
 * SS-mouse: check if this mouse button event should map into
 * function key
 */


static void
_map_button(chtype *inp)
{
    SLK_MAP *slk = SP->slk;
    int num = slk->_num;
    int len = slk->_len;
    int i;

    /* first determine if this mouse button event should be */
    /* mapped into function key             */

    if (!(SP->_map_mbe_to_key &
        ((BUTTON_CHANGED(3) << (10 + BUTTON_STATUS(3))) |
        (BUTTON_CHANGED(2) << (5 + BUTTON_STATUS(2)))  |
        (BUTTON_CHANGED(1) << BUTTON_STATUS(1)))))
        return;

    for (i = 0; i < num; i++) {
        if (MOUSE_X_POS < slk->_labx[i])
            break;
        if (MOUSE_X_POS > slk->_labx[i] + len)
            continue;
        *inp = KEY_F(1) + i;
        break;
    }
}