Import libusb 1.0.9-rc3 into third_party

third_party/libusb/libusb/os/poll_windows.h

Index: third_party/libusb/libusb/os/poll_windows.h
diff --git a/third_party/libusb/libusb/os/poll_windows.h b/third_party/libusb/libusb/os/poll_windows.h
new file mode 100644
index 0000000000000000000000000000000000000000..27986b871a29c0289204d9b924385fd975ecfed1
--- /dev/null
+++ b/third_party/libusb/libusb/os/poll_windows.h
@@ -0,0 +1,118 @@
+/*
+ * Windows compat: POSIX compatibility wrapper
+ * Copyright (C) 2009-2010 Pete Batard <pbatard@gmail.com>
+ * With contributions from Michael Plante, Orin Eman et al.
+ * Parts of poll implementation from libusb-win32, by Stephan Meyer et al.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ *
+ */
+
+#ifndef LIBUSB_POLL_WINDOWS_H
+#define LIBUSB_POLL_WINDOWS_H
+#pragma once
+
+#if defined(_MSC_VER)
+// disable /W4 MSVC warnings that are benign
+#pragma warning(disable:4127) // conditional expression is constant
+#endif
+
+// Uncomment to have poll return with EINTR as soon as a new transfer (fd) is added
+// This should result in a LIBUSB_ERROR_INTERRUPTED being returned by libusb calls,
+// which should give the app an opportunity to resubmit a new fd set.
+//#define DYNAMIC_FDS
+
+// Handle synchronous completion through the overlapped structure
+#if !defined(STATUS_REPARSE)	// reuse the REPARSE status code
+#define STATUS_REPARSE ((LONG)0x00000104L)
+#endif
+#define STATUS_COMPLETED_SYNCHRONOUSLY	STATUS_REPARSE
+#define HasOverlappedIoCompletedSync(lpOverlapped)	(((DWORD)(lpOverlapped)->Internal) == STATUS_COMPLETED_SYNCHRONOUSLY)
+
+#define DUMMY_HANDLE ((HANDLE)(LONG_PTR)-2)
+
+enum windows_version {
+	WINDOWS_UNSUPPORTED,
+	WINDOWS_XP,
+	WINDOWS_2003,	// also includes XP 64
+	WINDOWS_VISTA_AND_LATER,
+};
+extern enum windows_version windows_version;
+
+#define MAX_FDS     256
+
+#define POLLIN      0x0001    /* There is data to read */
+#define POLLPRI     0x0002    /* There is urgent data to read */
+#define POLLOUT     0x0004    /* Writing now will not block */
+#define POLLERR     0x0008    /* Error condition */
+#define POLLHUP     0x0010    /* Hung up */
+#define POLLNVAL    0x0020    /* Invalid request: fd not open */
+
+// access modes
+enum rw_type {
+	RW_NONE,
+	RW_READ,
+	RW_WRITE,
+};
+
+// fd struct that can be used for polling on Windows
+struct winfd {
+	int fd;							// what's exposed to libusb core
+	HANDLE handle;					// what we need to attach overlapped to the I/O op, so we can poll it
+	OVERLAPPED* overlapped;			// what will report our I/O status
+	enum rw_type rw;				// I/O transfer direction: read *XOR* write (NOT BOTH)
+};
+extern const struct winfd INVALID_WINFD;
+
+int usbi_pipe(int pipefd[2]);
+int usbi_poll(struct pollfd *fds, unsigned int nfds, int timeout);
+ssize_t usbi_write(int fd, const void *buf, size_t count);
+ssize_t usbi_read(int fd, void *buf, size_t count);
+int usbi_close(int fd);
+
+void init_polling(void);
+void exit_polling(void);
+struct winfd usbi_create_fd(HANDLE handle, int access_mode);
+void usbi_free_fd(int fd);
+struct winfd fd_to_winfd(int fd);
+struct winfd handle_to_winfd(HANDLE handle);
+struct winfd overlapped_to_winfd(OVERLAPPED* overlapped);
+
+/*
+ * Timeval operations
+ */
+#if defined(DDKBUILD)
+#include <winsock.h>	// defines timeval functions on DDK
+#endif
+
+#if !defined(TIMESPEC_TO_TIMEVAL)
+#define TIMESPEC_TO_TIMEVAL(tv, ts) {                   \
+	(tv)->tv_sec = (long)(ts)->tv_sec;                  \
+	(tv)->tv_usec = (long)(ts)->tv_nsec / 1000;         \
+}
+#endif
+#if !defined(timersub)
+#define timersub(a, b, result)                          \
+do {                                                    \
+	(result)->tv_sec = (a)->tv_sec - (b)->tv_sec;       \
+	(result)->tv_usec = (a)->tv_usec - (b)->tv_usec;    \
+	if ((result)->tv_usec < 0) {                        \
+		--(result)->tv_sec;                             \
+		(result)->tv_usec += 1000000;                   \
+	}                                                   \
+} while (0)
+#endif
+
+#endif /* LIBUSB_POLL_WINDOWS_H */