From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41200) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZrSQU-0004Uq-9C for qemu-devel@nongnu.org; Wed, 28 Oct 2015 11:14:11 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZrSQT-0007Ew-8X for qemu-devel@nongnu.org; Wed, 28 Oct 2015 11:14:10 -0400 Received: from mailhub.sw.ru ([195.214.232.25]:32233 helo=relay.sw.ru) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZrSQS-0007Dp-QB for qemu-devel@nongnu.org; Wed, 28 Oct 2015 11:14:09 -0400 From: "Denis V. Lunev" Date: Wed, 28 Oct 2015 18:13:57 +0300 Message-Id: <1446045237-19532-4-git-send-email-den@openvz.org> In-Reply-To: <1446045237-19532-1-git-send-email-den@openvz.org> References: <1446045237-19532-1-git-send-email-den@openvz.org> Subject: [Qemu-devel] [PATCH 3/3] qga: set file descriptor in qmp_guest_file_open non-blocking on Win32 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Michael Roth , Olga Krishtal , Stefan Weil , qemu-devel@nongnu.org, "Denis V. Lunev" From: Olga Krishtal Set fd non-blocking to avoid common use cases (like reading from a named pipe) from hanging the agent. This was missed in the original code. The patch introduces qemu_set_handle_nonoblocking, the local analog of qemu_set_nonblock for HANDLES. The usage of handles in qemu_set_non/block is impossible, because for win32 there is a difference between file discriptors and file handles, and all file ops are made via Win32 api. Signed-off-by: Olga Krishtal Signed-off-by: Denis V. Lunev CC: Michael Roth CC: Stefan Weil --- qga/commands-win32.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) diff --git a/qga/commands-win32.c b/qga/commands-win32.c index 97f19d5..a5306e7 100644 --- a/qga/commands-win32.c +++ b/qga/commands-win32.c @@ -128,6 +128,28 @@ static GuestFileHandle *guest_file_handle_find(int64_t id, Error **errp) return NULL; } +static void handle_set_nonblocking(HANDLE fh) +{ + DWORD file_type, pipe_state; + file_type = GetFileType(fh); + if (file_type != FILE_TYPE_PIPE) { + return; + } + /* If file_type == FILE_TYPE_PIPE, according to MSDN + * the specified file is socket or named pipe */ + if (!GetNamedPipeHandleState(fh, &pipe_state, NULL, + NULL, NULL, NULL, 0)) { + return; + } + /* The fd is named pipe fd */ + if (pipe_state & PIPE_NOWAIT) { + return; + } + + pipe_state |= PIPE_NOWAIT; + SetNamedPipeHandleState(fh, &pipe_state, NULL, NULL); +} + int64_t qmp_guest_file_open(const char *path, bool has_mode, const char *mode, Error **errp) { @@ -158,6 +180,11 @@ int64_t qmp_guest_file_open(const char *path, bool has_mode, return -1; } + /* set fd non-blocking to avoid common use cases (like reading from a + * named pipe) from hanging the agent + */ + handle_set_nonblocking(fh); + fd = guest_file_handle_add(fh, errp); if (fd < 0) { CloseHandle(fh); -- 2.1.4