xz: Fix the fcntl() usage when creating a pipe for the self-pipe trick.
Now it reads the old flags instead of blindly setting O_NONBLOCK.
The old code may have worked correctly, but this is better.
diff --git a/src/xz/file_io.c b/src/xz/file_io.c
index c52656c..9bd515d 100644
--- a/src/xz/file_io.c
+++ b/src/xz/file_io.c
@@ -82,13 +82,19 @@
// we are root.
warn_fchown = geteuid() == 0;
- if (pipe(user_abort_pipe)
- || fcntl(user_abort_pipe[0], F_SETFL, O_NONBLOCK)
- == -1
- || fcntl(user_abort_pipe[1], F_SETFL, O_NONBLOCK)
- == -1)
+ // Create a pipe for the self-pipe trick.
+ if (pipe(user_abort_pipe))
message_fatal(_("Error creating a pipe: %s"),
strerror(errno));
+
+ // Make both ends of the pipe non-blocking.
+ for (unsigned i = 0; i < 2; ++i) {
+ int flags = fcntl(user_abort_pipe[i], F_GETFL);
+ if (flags == -1 || fcntl(user_abort_pipe[i], F_SETFL,
+ flags | O_NONBLOCK) == -1)
+ message_fatal(_("Error creating a pipe: %s"),
+ strerror(errno));
+ }
#endif
#ifdef __DJGPP__
