/*

 * Windows compat: POSIX compatibility wrapper

 * Copyright © 2012-2013 RealVNC Ltd.

 * Copyright © 2009-2010 Pete Batard <pete@akeo.ie>

 * Copyright © 2016-2018 Chris Dickens <christopher.a.dickens@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

 *

 */

#pragma once

#if defined(_MSC_VER)

// disable /W4 MSVC warnings that are benign

#pragma warning(disable:4127) // conditional expression is constant

#endif

// 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

#if defined(_WIN32_WCE)

// WinCE doesn't have a HasOverlappedIoCompleted() macro, so attempt to emulate it

#define HasOverlappedIoCompleted(lpOverlapped) (((DWORD)(lpOverlapped)->Internal) != STATUS_PENDING)

#endif

#define HasOverlappedIoCompletedSync(lpOverlapped)	(((DWORD)(lpOverlapped)->Internal) == STATUS_COMPLETED_SYNCHRONOUSLY)

#define DUMMY_HANDLE ((HANDLE)(LONG_PTR)-2)

#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 */

struct pollfd {

	int fd;		/* file descriptor */

	short events;	/* requested events */

	short revents;	/* returned events */

};

struct winfd {

	int fd;				// what's exposed to libusb core

	OVERLAPPED *overlapped;		// what will report our I/O status

};

extern const struct winfd INVALID_WINFD;

struct winfd usbi_create_fd(void);

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 usbi_inc_fds_ref(struct pollfd *fds, unsigned int nfds);

void usbi_dec_fds_ref(struct pollfd *fds, unsigned int nfds);

/*

 * 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