ui: work around libtermkey bug when stdin is /dev/null

Libtermkey tries to write a terminal initialization sequence even when
stdin is not a terminal as is the case when running `vis < /dev/null`
or within the Travis CI environment.

The broken code is in libtermkey's driver-ti.c function `start_driver`:

  /* There's no point trying to write() to a pipe */
  if(fstat(tk->fd, &statbuf) == -1)
    return 0;

  if(S_ISFIFO(statbuf.st_mode))
    return 1;

Instead they should simply be using isatty(3).

As a workaround we catch the resulting EBADF failure and try to re-open
/dev/tty as stdin. If this fails too (as is the case in the Mac OS X
Travis CI runner) create an abstract termkey instance instead. In this
state vis will not be able to consume any input and will instead spin
with 100% CPU usage in the mainloop. This is solely done to make the Lua
tests, which control vis through other means, work within the Travis CI
environment.

0 files changed, 0 insertions, 0 deletions