diff options
| -rw-r--r-- | qga/commands-win32.c | 27 |
1 files changed, 27 insertions, 0 deletions
diff --git a/qga/commands-win32.c b/qga/commands-win32.c index 97f19d5392..a5306e76b0 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); |