lib_twait.c

[Philippe Blain]

>From Philippe Blain, Bordeaux, FRANCE - <address@hidden>
My very old computer: P133 - 8,4 Go - 32 Mo Red Hat Linux 7.0
I have a dream (P-IV 40Go Geforce4 flat screen...)

To maintainers of 'ncurses'.(and to Mr Dickey)
Subject: Corrections for ncurses-5.2-20020803+

Here are some problems I found:

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Thanks for your response about lib_getch.c. I'm going to investigate more
about
that if I can.
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File : ncurses/tty/lib_twait.c

Function : _nc_timed_wait(int mode, int milliseconds, int *timeleft)

OK, infinite timeout seems good now.

Just a little remark:
The code makes no difference between returning an error
because functions have failed (poll, select or ioctl) and when no file
descriptors have changed status.
The return value is 0 in both cases.

It's possible to return (-1) when functions fail by just modifying the end
or forcing "if (result==-1) return(-1);" just after poll, select or ioctl.
All possible returns values would be :
        0    - no activity
        1    - datas on input descriptor
        2    - mouse activity
        3    - activity on input and mouse
        (-1) - Error, errno is set.
And then testing as "if (_nc_timed_wait(...) > 0)" in lib_getch.c,
lib_mouse.c.

This would permit to test errno==EINTR in the mouse code for lib_getch.c

..........
#if USE_GPM_SUPPORT || defined(USE_EMX_MOUSE)
 /* Infinite timeout, waiting for mouse or key */
    if ((SP->_mouse_fd >= 0)
==>     && ((n = _nc_timed_wait(3, -1, (int *) 0)) & 2)) {
 /* Prefer mouse activity first*/
        SP->_mouse_event(SP);
        ch = KEY_MOUSE;
    } else
#endif
    {
 /* else keyboard activity */
        unsigned char c2 = 0;
        n = read(SP->_ifd, &c2, 1);
        ch = c2;
    }

#ifdef HIDE_EINTR
 /* Interrupted by a non-restarting signal */
 /* Now, as n==-1 because _nc_timed_wait failed, goto again */
    if (n <= 0 && errno == EINTR)
        goto again;
#endif
..........

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- Philippe