/* This Source Code Form is subject to the terms of the Mozilla Public

 * License, v. 2.0. If a copy of the MPL was not distributed with this

 * file, You can obtain one at http://mozilla.org/MPL/2.0/.

 *

 *    Copyright 2021 (c) Fraunhofer IOSB (Author: Julius Pfrommer)

 *    Copyright 2021 (c) Fraunhofer IOSB (Author: Jan Hermes)

 */

#ifndef UA_EVENTLOOP_POSIX_H_

#define UA_EVENTLOOP_POSIX_H_

#include <open62541/config.h>

#include <open62541/plugin/eventloop.h>

#if defined(UA_ARCHITECTURE_POSIX) || defined(UA_ARCHITECTURE_WIN32)

#include "common/ua_timer.h"

#include "open62541_queue.h"

/* epoll_pwait returns bogus data with the tc compiler */

#if defined(__linux__) && !defined(__TINYC__)

# define UA_HAVE_EPOLL

# include <sys/epoll.h>

#endif

#define UA_MAXBACKLOG 100

#define UA_MAXHOSTNAME_LENGTH 256

#define UA_MAXPORTSTR_LENGTH 6

#ifndef MSG_NOSIGNAL

#define MSG_NOSIGNAL 0

#endif

#ifndef MSG_DONTWAIT

#define MSG_DONTWAIT 0

#endif

_UA_BEGIN_DECLS

/* POSIX events are based on sockets / file descriptors. The EventSources can

 * register their fd in the EventLoop so that they are considered by the

 * EventLoop dropping into "poll" to wait for events. */

/* TODO: Move the macro-forest from /arch/<arch>/ua_architecture.h */

#define UA_FD UA_SOCKET

#define UA_INVALID_FD UA_INVALID_SOCKET

struct UA_RegisteredFD;

typedef struct UA_RegisteredFD UA_RegisteredFD;

/* Bitmask to be used for the UA_FDCallback event argument */

#define UA_FDEVENT_IN 1

#define UA_FDEVENT_OUT 2

#define UA_FDEVENT_ERR 4

typedef void (*UA_FDCallback)(UA_EventSource *es, UA_RegisteredFD *rfd, short event);

struct UA_RegisteredFD {

    UA_DelayedCallback dc; /* Used for async closing. Must be the first member

                            * because the rfd is freed by the delayed callback

                            * mechanism. */

    ZIP_ENTRY(UA_RegisteredFD) zipPointers; /* Register FD in the EventSource */

    UA_FD fd;

    short listenEvents; /* UA_FDEVENT_IN | UA_FDEVENT_OUT*/

    UA_EventSource *es; /* Backpointer to the EventSource */

    UA_FDCallback eventSourceCB;

};

enum ZIP_CMP cmpFD(const UA_FD *a, const UA_FD *b);

typedef ZIP_HEAD(UA_FDTree, UA_RegisteredFD) UA_FDTree;

ZIP_FUNCTIONS(UA_FDTree, UA_RegisteredFD, zipPointers, UA_FD, fd, cmpFD)

/* All ConnectionManager in the POSIX EventLoop can be cast to

 * UA_ConnectionManagerPOSIX. They carry a sorted tree of their open

 * sockets/file-descriptors. */

typedef struct {

    UA_ConnectionManager cm;

    /* Reused receive buffer. The size is configured via

     * the recv-bufsize parameter.*/

    UA_ByteString rxBuffer;

    /* Sorted tree of the FDs */

    size_t fdsSize;

    UA_FDTree fds;

} UA_POSIXConnectionManager;

typedef struct {

    UA_EventLoop eventLoop;

    /* Timer */

    UA_Timer timer;

    /* Linked List of Delayed Callbacks */

    UA_DelayedCallback *delayedCallbacks;

    /* Flag determining whether the eventloop is currently within the

     * "run" method */

    UA_Boolean executing;

#if defined(UA_HAVE_EPOLL)

    UA_FD epollfd;

#else

    UA_RegisteredFD **fds;

    size_t fdsSize;

#endif

#if UA_MULTITHREADING >= 100

    UA_Lock elMutex;

#endif

} UA_EventLoopPOSIX;

/*

 * The following functions differ between epoll and normal select

 */

/* Register to start receiving events */

UA_StatusCode

UA_EventLoopPOSIX_registerFD(UA_EventLoopPOSIX *el, UA_RegisteredFD *rfd);

/* Modify the events that the fd listens on */

UA_StatusCode

UA_EventLoopPOSIX_modifyFD(UA_EventLoopPOSIX *el, UA_RegisteredFD *rfd);

/* Deregister but do not close the fd. No further events are received. */

void

UA_EventLoopPOSIX_deregisterFD(UA_EventLoopPOSIX *el, UA_RegisteredFD *rfd);

UA_StatusCode

UA_EventLoopPOSIX_pollFDs(UA_EventLoopPOSIX *el, UA_DateTime listenTimeout);

/* Helper functions between EventSources */

UA_StatusCode

UA_EventLoopPOSIX_allocateRXBuffer(UA_POSIXConnectionManager *pcm);

UA_StatusCode

UA_EventLoopPOSIX_allocNetworkBuffer(UA_ConnectionManager *cm,

                                     uintptr_t connectionId,

                                     UA_ByteString *buf,

                                     size_t bufSize);

void

UA_EventLoopPOSIX_freeNetworkBuffer(UA_ConnectionManager *cm,

                                    uintptr_t connectionId,

                                    UA_ByteString *buf);

/*

 * Helper functions to be used across protocols

 */

/* Set the socket non-blocking. If the listen-socket is nonblocking, incoming

 * connections inherit this state. */

UA_StatusCode

UA_EventLoopPOSIX_setNonBlocking(UA_FD sockfd);

/* Don't have the socket create interrupt signals */

UA_StatusCode

UA_EventLoopPOSIX_setNoSigPipe(UA_FD sockfd);

/* Enables sharing of the same listening address on different sockets */

UA_StatusCode

UA_EventLoopPOSIX_setReusable(UA_FD sockfd);

_UA_END_DECLS

#endif /* defined(UA_ARCHITECTURE_POSIX) || defined(UA_ARCHITECTURE_WIN32) */

#endif /* UA_EVENTLOOP_POSIX_H_ */