- NtReadFile() and NtWriteFile() seems to return STATUS_PENDING occasionally even in nonblocking mode. This patch adds handling for STATUS_PENDING in nonblocking mode.
Addresses: https://cygwin.com/pipermail/cygwin/2021-November/249910.html --- winsup/cygwin/fhandler_pipe.cc | 10 ++++++---- winsup/cygwin/release/3.3.3 | 5 +++++ 2 files changed, 11 insertions(+), 4 deletions(-) diff --git a/winsup/cygwin/fhandler_pipe.cc b/winsup/cygwin/fhandler_pipe.cc index 1ebf4de10..f70ff56fe 100644 --- a/winsup/cygwin/fhandler_pipe.cc +++ b/winsup/cygwin/fhandler_pipe.cc @@ -336,9 +336,10 @@ fhandler_pipe::raw_read (void *ptr, size_t& len) break; status = NtReadFile (get_handle (), evt, NULL, NULL, &io, ptr, len1, NULL, NULL); - if (evt && status == STATUS_PENDING) + if (status == STATUS_PENDING) { - waitret = cygwait (evt, INFINITE, cw_cancel | cw_sig); + HANDLE w = evt ?: get_handle (); + waitret = cygwait (w, INFINITE, cw_cancel | cw_sig); /* If io.Status is STATUS_CANCELLED after CancelIo, IO has actually been cancelled and io.Information contains the number of bytes processed so far. @@ -507,10 +508,11 @@ fhandler_pipe_fifo::raw_write (const void *ptr, size_t len) break; len1 >>= 1; } - if (evt && status == STATUS_PENDING) + if (status == STATUS_PENDING) { + HANDLE w = evt ?: get_handle (); while (WAIT_TIMEOUT == - (waitret = cygwait (evt, (DWORD) 0, cw_cancel | cw_sig))) + (waitret = cygwait (w, (DWORD) 0, cw_cancel | cw_sig))) { if (reader_closed ()) { diff --git a/winsup/cygwin/release/3.3.3 b/winsup/cygwin/release/3.3.3 index 1eb25e2fc..49c1bcdc3 100644 --- a/winsup/cygwin/release/3.3.3 +++ b/winsup/cygwin/release/3.3.3 @@ -16,3 +16,8 @@ Bug Fixes - Fix long-standing problem that new files don't get created with the FILE_ATTRIBUTE_ARCHIVE DOS attribute set. Addresses: https://cygwin.com/pipermail/cygwin/2021-November/249909.html + +- Fix issue that pipe read()/write() occationally returns a garnage + length when NtReadFile/NtWriteFile returns STATUS_PENDING in non- + blocking mode. + Addresses: https://cygwin.com/pipermail/cygwin/2021-November/249910.html -- 2.33.0
