open-file: allow async signals.

With this patch, if open-file blocks (for instance on a FIFO
or device), it is interruptible. In the listener, the
operation can be aborted with Ctrl-C now.

* stream.c (w_fopen_mode): If we HAVE_FCNTL, then handle all
file opening via open + fdopen, rather than fopen. On
platforms where we use fopen, interruptibility won't work.
The fopen function cannot be abandoned via an exception thrown
from a signal handler because it performs memory allocation.
Because we need a temporary UTF-8 string to do the open,
which might be abandoned by a signal, let's move the string to
the stack via alloca, and free the original, so we don't have
to set up unwinding to free it.

0 files changed, 0 insertions, 0 deletions