[MPlayer-dev-eng] [PATCH] fix for mplayer input bugs: shooting to memory+lost events

[Stephen Stocker]

  Hi,

  This patch was submitted by Mikulas on June 30, and I wonder if
  someone could please look at it and apply if it's OK?

  Its fixes a bug which occurs with SVGAlib, where if you hold down the
  left arrow key to back up to the start of a video (or any key, for
  that matter), then hit some other key (to change brightness, for
  example), MPlayer will back up to the start of the video again.

  This patch still works on current CVS, btw. Here's the URL and a copy
  of the original post. Thanks!

  Steve

http://mplayerhq.hu/pipermail/mplayer-users/2004-June/046528.html

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 Hi

 This patch fixes two problems in mplayer input key system:

 1. shooting to stack when only partial data are read from pipe (note that
 when adding number to pointer, the number is multiplied by size of pointer
 type).

 2. delayed events on svgalib:

 The problem is caused by getch2, getch2 does buffering of handle 0,
 however getch2 is called only when handle 0 is reported as readable by
 select.

 It manifests like this:
 - User holds key so that key repeat rate is higher than frame rate
         (key presses are put into buffer in getch2)
 - User releases key
         (handle 0 is no longer reported as readable, however there are
          still charactes in getch2 buffer, but getch2 is not called
          anymore)
 - User presses another key --- few keypresses of previous key are still
 processed.
         (getch2 is called and previous content of getch2 buffer is
          processed)

 The patch changes it so that getch2 is always called regardless of select
 state of handle 0 --- it makes sense because getch2 calls select itself.

 Mikulas

 --- input/input.c_      2004-06-30 02:04:43.000000000 +0100
 +++ input/input.c       2004-06-30 02:25:50.000000000 +0100
 @@ -656,7 +656,7 @@
    unsigned int l;
    l = 0;
    while(l < sizeof(int)) {
 -    r = read(fd,(&code)+l,sizeof(int)-l);
 +    r = read(fd,((char *)&code)+l,sizeof(int)-l);
      if(r <= 0)
        break;
      l +=r;
 @@ -902,7 +902,7 @@
      }
  #ifndef HAVE_NO_POSIX_SELECT
      // No input from this fd
 -    if(! (key_fds[i].flags & MP_FD_NO_SELECT) && ! FD_ISSET(key_fds[i].fd,&fds))
 +    if(! (key_fds[i].flags & MP_FD_NO_SELECT) && ! FD_ISSET(key_fds[i].fd,&fds) && key_fds[i].fd != 0)
        continue;
  #endif
      if(key_fds[i].fd == 0) { // stdin is handled by getch2


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