5 meshlink-tiny++.h -- MeshLink C++ API
6 Copyright (C) 2014, 2017 Guus Sliepen <guus@meshlink.io>
8 This program is free software; you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 2 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License along
19 with this program; if not, write to the Free Software Foundation, Inc.,
20 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
23 #include <meshlink-tiny.h>
24 #include <new> // for 'placement new'
31 /// Severity of log messages generated by MeshLink.
32 typedef meshlink_log_level_t log_level_t;
34 /// Code of most recent error encountered.
35 typedef meshlink_errno_t errno_t;
37 /// A callback for receiving data from the mesh.
38 /** @param mesh A handle which represents an instance of MeshLink.
39 * @param source A pointer to a meshlink::node describing the source of the data.
40 * @param data A pointer to a buffer containing the data sent by the source.
41 * @param len The length of the received data.
43 typedef void (*receive_cb_t)(mesh *mesh, node *source, const void *data, size_t len);
45 /// A callback reporting the meta-connection attempt made by the host node to an another node.
46 /** @param mesh A handle which represents an instance of MeshLink.
47 * @param node A pointer to a meshlink_node_t describing the node to whom meta-connection is being tried.
48 * This pointer is valid until meshlink_close() is called.
50 typedef void (*connection_try_cb_t)(mesh *mesh, node *node);
52 /// A callback reporting node status changes.
53 /** @param mesh A handle which represents an instance of MeshLink.
54 * @param node A pointer to a meshlink::node describing the node whose status changed.
55 * @param reachable True if the node is reachable, false otherwise.
57 typedef void (*node_status_cb_t)(mesh *mesh, node *node, bool reachable);
59 /// A callback reporting duplicate node detection.
60 /** @param mesh A handle which represents an instance of MeshLink.
61 * @param node A pointer to a meshlink_node_t describing the node which is duplicate.
62 * This pointer is valid until meshlink_close() is called.
64 typedef void (*duplicate_cb_t)(mesh *mesh, node *node);
66 /// A callback for receiving log messages generated by MeshLink.
67 /** @param mesh A handle which represents an instance of MeshLink.
68 * @param level An enum describing the severity level of the message.
69 * @param text A pointer to a string containing the textual log message.
71 typedef void (*log_cb_t)(mesh *mesh, log_level_t level, const char *text);
73 /// A callback for listening for incoming channels.
74 /** @param mesh A handle which represents an instance of MeshLink.
75 * @param node A handle for the node that wants to open a channel.
76 * @param port The port number the peer wishes to connect to.
78 * @return This function should return true if the application listens for the incoming channel, false otherwise.
80 typedef bool (*meshlink_channel_listen_cb_t)(struct meshlink_handle *mesh, struct meshlink_node *node, uint16_t port);
82 /// A callback for accepting incoming channels.
83 /** @param mesh A handle which represents an instance of MeshLink.
84 * @param channel A handle for the incoming channel.
85 * @param port The port number the peer wishes to connect to.
86 * @param data A pointer to a buffer containing data already received. (Not yet used.)
87 * @param len The length of the data. (Not yet used.)
89 * @return This function should return true if the application accepts the incoming channel, false otherwise.
90 * If returning false, the channel is invalid and may not be used anymore.
92 typedef bool (*channel_accept_cb_t)(mesh *mesh, channel *channel, uint16_t port, const void *data, size_t len);
94 /// A callback for receiving data from a channel.
95 /** @param mesh A handle which represents an instance of MeshLink.
96 * @param channel A handle for the channel.
97 * @param data A pointer to a buffer containing data sent by the source.
98 * @param len The length of the data.
100 typedef void (*channel_receive_cb_t)(mesh *mesh, channel *channel, const void *data, size_t len);
102 /// A callback that is called when data can be send on a channel.
103 /** @param mesh A handle which represents an instance of MeshLink.
104 * @param channel A handle for the channel.
105 * @param len The maximum length of data that is guaranteed to be accepted by a call to channel_send().
107 typedef void (*channel_poll_cb_t)(mesh *mesh, channel *channel, size_t len);
109 /// A class describing a MeshLink node.
110 class node: public meshlink_node_t {
113 /// A class describing a MeshLink channel.
114 class channel: public meshlink_channel_t {
116 static const uint32_t RELIABLE = MESHLINK_CHANNEL_RELIABLE;
117 static const uint32_t ORDERED = MESHLINK_CHANNEL_ORDERED;
118 static const uint32_t FRAMED = MESHLINK_CHANNEL_FRAMED;
119 static const uint32_t DROP_LATE = MESHLINK_CHANNEL_DROP_LATE;
120 static const uint32_t NO_PARTIAL = MESHLINK_CHANNEL_NO_PARTIAL;
121 static const uint32_t TCP = MESHLINK_CHANNEL_TCP;
122 static const uint32_t UDP = MESHLINK_CHANNEL_UDP;
125 /// A class describing a MeshLink mesh.
128 mesh() : handle(0) {}
134 bool isOpen() const {
135 return (handle != 0);
138 // TODO: please enable C++11 in autoconf to enable "move constructors":
139 // mesh(mesh&& other)
140 // : handle(other.handle)
143 // handle->priv = this;
147 /// Initialize MeshLink's configuration directory.
148 /** This function causes MeshLink to initialize its configuration directory,
149 * if it hasn't already been initialized.
150 * It only has to be run the first time the application starts,
151 * but it is not a problem if it is run more than once, as long as
152 * the arguments given are the same.
154 * This function does not start any network I/O yet. The application should
155 * first set callbacks, and then call meshlink_start().
157 * @param confbase The directory in which MeshLink will store its configuration files.
158 * @param name The name which this instance of the application will use in the mesh.
159 * @param appname The application name which will be used in the mesh.
160 * @param devclass The device class which will be used in the mesh.
162 * @return This function will return a pointer to a meshlink::mesh if MeshLink has successfully set up its configuration files, NULL otherwise.
164 bool open(const char *confbase, const char *name, const char *appname, dev_class_t devclass) {
165 handle = meshlink_open(confbase, name, appname, devclass);
174 mesh(const char *confbase, const char *name, const char *appname, dev_class_t devclass) {
175 open(confbase, name, appname, devclass);
178 /// Close the MeshLink handle.
179 /** This function calls meshlink_stop() if necessary,
180 * and frees all memory allocated by MeshLink.
181 * Afterwards, the handle and any pointers to a struct meshlink_node are invalid.
186 meshlink_close(handle);
192 /** instead of registerin callbacks you derive your own class and overwrite the following abstract member functions.
193 * These functions are run in MeshLink's own thread.
194 * It is therefore important that these functions use apprioriate methods (queues, pipes, locking, etc.)
195 * to hand the data over to the application's thread.
196 * These functions should also not block itself and return as quickly as possible.
197 * The default member functions are no-ops, so you are not required to overwrite all these member functions
200 /// This function is called whenever another node sends data to the local node.
201 virtual void receive(node *source, const void *data, size_t length) {
208 /// This functions is called whenever another node's status changed.
209 virtual void node_status(node *peer, bool reachable) {
215 /// This functions is called whenever a duplicate node is detected.
216 virtual void node_duplicate(node *peer) {
221 /// This functions is called whenever MeshLink has some information to log.
222 virtual void log(log_level_t level, const char *message) {
228 /// This functions is called whenever MeshLink has encountered a serious error.
229 virtual void error(meshlink_errno_t meshlink_errno) {
231 (void)meshlink_errno;
234 /// This functions is called whenever MeshLink a meta-connection attempt is made.
235 virtual void connection_try(node *peer) {
240 /// This functions is called to determine if we are listening for incoming channels.
242 * The function is run in MeshLink's own thread.
243 * It is therefore important that the callback uses apprioriate methods (queues, pipes, locking, etc.)
244 * to pass data to or from the application's thread.
245 * The callback should also not block itself and return as quickly as possible.
247 * @param node A handle for the node that wants to open a channel.
248 * @param port The port number the peer wishes to connect to.
250 * @return This function should return true if the application accepts the incoming channel, false otherwise.
252 virtual bool channel_listen(node *node, uint16_t port) {
253 /* by default accept all channels */
259 /// This functions is called whenever another node attempts to open a channel to the local node.
261 * If the channel is accepted, the poll_callback will be set to channel_poll and can be
262 * changed using set_channel_poll_cb(). Likewise, the receive callback is set to
265 * The function is run in MeshLink's own thread.
266 * It is therefore important that the callback uses apprioriate methods (queues, pipes, locking, etc.)
267 * to pass data to or from the application's thread.
268 * The callback should also not block itself and return as quickly as possible.
270 * @param channel A handle for the incoming channel.
271 * @param port The port number the peer wishes to connect to.
272 * @param data A pointer to a buffer containing data already received. (Not yet used.)
273 * @param len The length of the data. (Not yet used.)
275 * @return This function should return true if the application accepts the incoming channel, false otherwise.
276 * If returning false, the channel is invalid and may not be used anymore.
278 virtual bool channel_accept(channel *channel, uint16_t port, const void *data, size_t len) {
279 /* by default reject all channels */
287 /// This function is called by Meshlink for receiving data from a channel.
289 * The function is run in MeshLink's own thread.
290 * It is therefore important that the callback uses apprioriate methods (queues, pipes, locking, etc.)
291 * to pass data to or from the application's thread.
292 * The callback should also not block itself and return as quickly as possible.
294 * @param channel A handle for the channel.
295 * @param data A pointer to a buffer containing data sent by the source.
296 * @param len The length of the data.
298 virtual void channel_receive(channel *channel, const void *data, size_t len) {
305 /// This function is called by Meshlink when data can be send on a channel.
307 * The function is run in MeshLink's own thread.
308 * It is therefore important that the callback uses apprioriate methods (queues, pipes, locking, etc.)
309 * to pass data to or from the application's thread.
311 * The callback should also not block itself and return as quickly as possible.
312 * @param channel A handle for the channel.
313 * @param len The maximum length of data that is guaranteed to be accepted by a call to channel_send().
315 virtual void channel_poll(channel *channel, size_t len) {
322 /** This function causes MeshLink to open network sockets, make outgoing connections, and
323 * create a new thread, which will handle all network I/O.
325 * @return This function will return true if MeshLink has successfully started its thread, false otherwise.
328 meshlink_set_receive_cb(handle, &receive_trampoline);
329 meshlink_set_node_status_cb(handle, &node_status_trampoline);
330 meshlink_set_node_duplicate_cb(handle, &node_duplicate_trampoline);
331 meshlink_set_log_cb(handle, MESHLINK_DEBUG, &log_trampoline);
332 meshlink_set_error_cb(handle, &error_trampoline);
333 meshlink_set_channel_listen_cb(handle, &channel_listen_trampoline);
334 meshlink_set_channel_accept_cb(handle, &channel_accept_trampoline);
335 meshlink_set_connection_try_cb(handle, &connection_try_trampoline);
336 return meshlink_start(handle);
340 /** This function causes MeshLink to disconnect from all other nodes,
341 * close all sockets, and shut down its own thread.
344 meshlink_stop(handle);
347 /// Send data to another node.
348 /** This functions sends one packet of data to another node in the mesh.
349 * The packet is sent using UDP semantics, which means that
350 * the packet is sent as one unit and is received as one unit,
351 * and that there is no guarantee that the packet will arrive at the destination.
352 * The application should take care of getting an acknowledgement and retransmission if necessary.
354 * @param destination A pointer to a meshlink::node describing the destination for the data.
355 * @param data A pointer to a buffer containing the data to be sent to the source.
356 * @param len The length of the data.
357 * @return This function will return true if MeshLink has queued the message for transmission, and false otherwise.
358 * A return value of true does not guarantee that the message will actually arrive at the destination.
360 bool send(node *destination, const void *data, unsigned int len) {
361 return meshlink_send(handle, destination, data, len);
364 /// Get a handle for a specific node.
365 /** This function returns a handle for the node with the given name.
367 * @param name The name of the node for which a handle is requested.
369 * @return A pointer to a meshlink::node which represents the requested node,
370 * or NULL if the requested node does not exist.
372 node *get_node(const char *name) {
373 return (node *)meshlink_get_node(handle, name);
376 /// Get a node's reachability status.
377 /** This function returns the current reachability of a given node, and the times of the last state changes.
378 * If a given state change never happened, the time returned will be 0.
380 * @param node A pointer to a meshlink::node describing the node.
381 * @param last_reachable A pointer to a time_t variable that will be filled in with the last time the node became reachable.
382 * @param last_unreachable A pointer to a time_t variable that will be filled in with the last time the node became unreachable.
384 * @return This function returns true if the node is currently reachable, false otherwise.
386 bool get_node_reachability(node *node, time_t *last_reachable = NULL, time_t *last_unreachable = NULL) {
387 return meshlink_get_node_reachability(handle, node, last_reachable, last_unreachable);
390 /// Get a handle for our own node.
391 /** This function returns a handle for the local node.
393 * @return A pointer to a meshlink::node which represents the local node.
396 return (node *)meshlink_get_self(handle);
399 /// Get a list of all nodes.
400 /** This function returns a list with handles for all known nodes.
402 * @param nodes A pointer to an array of pointers to meshlink::node, which should be allocated by the application.
403 * @param nmemb The maximum number of pointers that can be stored in the nodes array.
405 * @return The number of known nodes, or -1 in case of an error.
406 * This can be larger than nmemb, in which case not all nodes were stored in the nodes array.
408 node **get_all_nodes(node **nodes, size_t *nmemb) {
409 return (node **)meshlink_get_all_nodes(handle, (meshlink_node_t **)nodes, nmemb);
412 /// Sign data using the local node's MeshLink key.
413 /** This function signs data using the local node's MeshLink key.
414 * The generated signature can be securely verified by other nodes.
416 * @param data A pointer to a buffer containing the data to be signed.
417 * @param len The length of the data to be signed.
418 * @param signature A pointer to a buffer where the signature will be stored.
419 * @param siglen The size of the signature buffer. Will be changed after the call to match the size of the signature itself.
421 * @return This function returns true if the signature is valid, false otherwise.
423 bool sign(const void *data, size_t len, void *signature, size_t *siglen) {
424 return meshlink_sign(handle, data, len, signature, siglen);
427 /// Verify the signature generated by another node of a piece of data.
428 /** This function verifies the signature that another node generated for a piece of data.
430 * @param source A pointer to a meshlink_node_t describing the source of the signature.
431 * @param data A pointer to a buffer containing the data to be verified.
432 * @param len The length of the data to be verified.
433 * @param signature A pointer to a string containing the signature.
434 * @param siglen The size of the signature.
436 * @return This function returns true if the signature is valid, false otherwise.
438 bool verify(node *source, const void *data, size_t len, const void *signature, size_t siglen) {
439 return meshlink_verify(handle, source, data, len, signature, siglen);
442 /// Set the canonical Address for a node.
443 /** This function sets the canonical Address for a node.
444 * This address is stored permanently until it is changed by another call to this function,
445 * unlike other addresses associated with a node,
446 * such as those added with meshlink_hint_address() or addresses discovered at runtime.
448 * If a canonical Address is set for the local node,
449 * it will be used for the hostname part of generated invitation URLs.
451 * @param node A pointer to a meshlink_node_t describing the node.
452 * @param address A nul-terminated C string containing the address, which can be either in numeric format or a hostname.
453 * @param port A nul-terminated C string containing the port, which can be either in numeric or symbolic format.
454 * If it is NULL, the listening port's number will be used.
456 * @return This function returns true if the address was added, false otherwise.
458 bool set_canonical_address(node *node, const char *address, const char *port = NULL) {
459 return meshlink_set_canonical_address(handle, node, address, port);
462 /// Clear the canonical Address for a node.
463 /** This function clears the canonical Address for a node.
465 * @param node A pointer to a struct meshlink_node describing the node.
467 * @return This function returns true if the address was removed, false otherwise.
469 bool clear_canonical_address(node *node) {
470 return meshlink_clear_canonical_address(handle, node);
473 /// Set the scheduling granularity of the application
474 /** This should be set to the effective scheduling granularity for the application.
475 * This depends on the scheduling granularity of the operating system, the application's
476 * process priority and whether it is running as realtime or not.
477 * The default value is 10000 (10 milliseconds).
479 * @param granularity The scheduling granularity of the application in microseconds.
481 void set_granularity(long granularity) {
482 meshlink_set_scheduling_granularity(handle, granularity);
485 /// Sets the storage policy used by MeshLink
486 /** This sets the policy MeshLink uses when it has new information about nodes.
487 * By default, all udpates will be stored to disk (unless an ephemeral instance has been opened).
488 * Setting the policy to MESHLINK_STORAGE_KEYS_ONLY, only updates that contain new keys for nodes
490 * By setting the policy to MESHLINK_STORAGE_DISABLED, no updates will be stored.
492 * @param policy The storage policy to use.
494 void set_storage_policy(meshlink_storage_policy_t policy) {
495 meshlink_set_storage_policy(handle, policy);
498 /// Use an invitation to join a mesh.
499 /** This function allows the local node to join an existing mesh using an invitation URL generated by another node.
500 * An invitation can only be used if the local node has never connected to other nodes before.
501 * After a successfully accepted invitation, the name of the local node may have changed.
503 * This function may only be called on a mesh that has not been started yet and which is not already part of an existing mesh.
505 * This function is blocking. It can take several seconds before it returns.
506 * There is no guarantee it will perform a successful join.
507 * Failures might be caused by temporary network outages, or by the invitation having expired.
509 * @param invitation A string containing the invitation URL.
511 * @return This function returns true if the local node joined the mesh it was invited to, false otherwise.
513 bool join(const char *invitation) {
514 return meshlink_join(handle, invitation);
517 /// Export the local node's key and addresses.
518 /** This function generates a string that contains the local node's public key and one or more IP addresses.
519 * The application can pass it in some way to another node, which can then import it,
520 * granting the local node access to the other node's mesh.
522 * @return This function returns a string that contains the exported key and addresses.
523 * The application should call free() after it has finished using this string.
526 return meshlink_export(handle);
529 /// Import another node's key and addresses.
530 /** This function accepts a string containing the exported public key and addresses of another node.
531 * By importing this data, the local node grants the other node access to its mesh.
533 * @param data A string containing the other node's exported key and addresses.
535 * @return This function returns true if the data was valid and the other node has been granted access to the mesh, false otherwise.
537 bool import_key(const char *data) {
538 return meshlink_import(handle, data);
541 /// Forget any information about a node.
542 /** This function allows the local node to forget any information it has about a node,
543 * and if possible will remove any data it has stored on disk about the node.
545 * Any open channels to this node must be closed before calling this function.
547 * After this call returns, the node handle is invalid and may no longer be used, regardless
548 * of the return value of this call.
550 * Note that this function does not prevent MeshLink from actually forgetting about a node,
551 * or re-learning information about a node at a later point in time. It is merely a hint that
552 * the application does not care about this node anymore and that any resources kept could be
555 * \memberof meshlink_node
556 * @param node A pointer to a struct meshlink_node describing the node to be forgotten.
558 * @return This function returns true if all currently known data about the node has been forgotten, false otherwise.
560 bool forget_node(node *node) {
561 return meshlink_forget_node(handle, node);
564 /// Set the send buffer size of a channel.
565 /** This function sets the desired size of the send buffer.
566 * The default size is 128 kB.
568 * @param channel A handle for the channel.
569 * @param size The desired size for the send buffer.
570 * If a NULL pointer is given, the callback will be disabled.
572 void set_channel_sndbuf(channel *channel, size_t size) {
573 meshlink_set_channel_sndbuf(handle, channel, size);
576 /// Set the receive buffer size of a channel.
577 /** This function sets the desired size of the receive buffer.
578 * The default size is 128 kB.
580 * @param channel A handle for the channel.
581 * @param size The desired size for the send buffer.
582 * If a NULL pointer is given, the callback will be disabled.
584 void set_channel_rcvbuf(channel *channel, size_t size) {
585 meshlink_set_channel_rcvbuf(handle, channel, size);
588 /// Set the flags of a channel.
589 /** This function allows changing some of the channel flags.
590 * Currently only MESHLINK_CHANNEL_NO_PARTIAL and MESHLINK_CHANNEL_DROP_LATE are supported, other flags are ignored.
591 * These flags only affect the local side of the channel with the peer.
592 * The changes take effect immediately.
594 * @param channel A handle for the channel.
595 * @param flags A bitwise-or'd combination of flags that set the semantics for this channel.
597 void set_channel_flags(channel *channel, uint32_t flags) {
598 meshlink_set_channel_flags(handle, channel, flags);
601 /// Set the send buffer storage of a channel.
602 /** This function provides MeshLink with a send buffer allocated by the application.
604 * @param channel A handle for the channel.
605 * @param buf A pointer to the start of the buffer.
606 * If a NULL pointer is given, MeshLink will use its own internal buffer again.
607 * @param size The size of the buffer.
609 void set_channel_sndbuf_storage(channel *channel, void *buf, size_t size) {
610 meshlink_set_channel_sndbuf_storage(handle, channel, buf, size);
613 /// Set the receive buffer storage of a channel.
614 /** This function provides MeshLink with a receive buffer allocated by the application.
616 * @param channel A handle for the channel.
617 * @param buf A pointer to the start of the buffer.
618 * If a NULL pointer is given, MeshLink will use its own internal buffer again.
619 * @param size The size of the buffer.
621 void set_channel_rcvbuf_storage(channel *channel, void *buf, size_t size) {
622 meshlink_set_channel_rcvbuf_storage(handle, channel, buf, size);
625 /// Set the connection timeout used for channels to the given node.
626 /** This sets the timeout after which unresponsive channels will be reported as closed.
627 * The timeout is set for all current and future channels to the given node.
629 * @param node The node to set the channel timeout for.
630 * @param timeout The timeout in seconds after which unresponsive channels will be reported as closed.
631 * The default is 60 seconds.
633 void set_node_channel_timeout(node *node, int timeout) {
634 meshlink_set_node_channel_timeout(handle, node, timeout);
637 /// Open a reliable stream channel to another node.
638 /** This function is called whenever a remote node wants to open a channel to the local node.
639 * The application then has to decide whether to accept or reject this channel.
641 * This function sets the channel poll callback to channel_poll_trampoline, which in turn
642 * calls channel_poll. To set a different, channel-specific poll callback, use set_channel_poll_cb.
644 * @param node The node to which this channel is being initiated.
645 * @param port The port number the peer wishes to connect to.
646 * @param cb A pointer to the function which will be called when the remote node sends data to the local node.
647 * @param data A pointer to a buffer containing data to already queue for sending.
648 * @param len The length of the data.
649 * If len is 0, the data pointer is copied into the channel's priv member.
650 * @param flags A bitwise-or'd combination of flags that set the semantics for this channel.
652 * @return A handle for the channel, or NULL in case of an error.
654 channel *channel_open(node *node, uint16_t port, channel_receive_cb_t cb, const void *data, size_t len, uint32_t flags = channel::TCP) {
655 channel *ch = (channel *)meshlink_channel_open_ex(handle, node, port, (meshlink_channel_receive_cb_t)cb, data, len, flags);
659 /// Open a reliable stream channel to another node.
660 /** This function is called whenever a remote node wants to open a channel to the local node.
661 * The application then has to decide whether to accept or reject this channel.
663 * This function sets the channel receive callback to channel_receive_trampoline,
664 * which in turn calls channel_receive.
666 * This function sets the channel poll callback to channel_poll_trampoline, which in turn
667 * calls channel_poll. To set a different, channel-specific poll callback, use set_channel_poll_cb.
669 * @param node The node to which this channel is being initiated.
670 * @param port The port number the peer wishes to connect to.
671 * @param data A pointer to a buffer containing data to already queue for sending.
672 * @param len The length of the data.
673 * If len is 0, the data pointer is copied into the channel's priv member.
674 * @param flags A bitwise-or'd combination of flags that set the semantics for this channel.
676 * @return A handle for the channel, or NULL in case of an error.
678 channel *channel_open(node *node, uint16_t port, const void *data, size_t len, uint32_t flags = channel::TCP) {
679 channel *ch = (channel *)meshlink_channel_open_ex(handle, node, port, &channel_receive_trampoline, data, len, flags);
683 /// Partially close a reliable stream channel.
684 /** This shuts down the read or write side of a channel, or both, without closing the handle.
685 * It can be used to inform the remote node that the local node has finished sending all data on the channel,
686 * but still allows waiting for incoming data from the remote node.
688 * @param channel A handle for the channel.
689 * @param direction Must be one of SHUT_RD, SHUT_WR or SHUT_RDWR.
691 void channel_shutdown(channel *channel, int direction) {
692 return meshlink_channel_shutdown(handle, channel, direction);
695 /// Close a reliable stream channel.
696 /** This informs the remote node that the local node has finished sending all data on the channel.
697 * It also causes the local node to stop accepting incoming data from the remote node.
698 * Afterwards, the channel handle is invalid and must not be used any more.
700 * It is allowed to call this function at any time on a valid handle, even inside callback functions.
701 * If called with a valid handle, this function always succeeds, otherwise the result is undefined.
703 * @param channel A handle for the channel.
705 void channel_close(meshlink_channel_t *channel) {
706 return meshlink_channel_close(handle, channel);
709 /// Abort a reliable stream channel.
710 /** This aborts a channel.
711 * Data that was in the send and receive buffers is dropped, so potentially there is some data that
712 * was sent on this channel that will not be received by the peer.
713 * Afterwards, the channel handle is invalid and must not be used any more.
715 * It is allowed to call this function at any time on a valid handle, even inside callback functions.
716 * If called with a valid handle, this function always succeeds, otherwise the result is undefined.
718 * @param channel A handle for the channel.
720 void channel_abort(meshlink_channel_t *channel) {
721 return meshlink_channel_abort(handle, channel);
724 /// Transmit data on a channel
725 /** This queues data to send to the remote node.
727 * @param channel A handle for the channel.
728 * @param data A pointer to a buffer containing data sent by the source.
729 * @param len The length of the data.
731 * @return The amount of data that was queued, which can be less than len, or a negative value in case of an error.
732 * If MESHLINK_CHANNEL_NO_PARTIAL is set, then the result will either be len,
733 * 0 if the buffer is currently too full, or -1 if len is too big even for an empty buffer.
735 ssize_t channel_send(channel *channel, void *data, size_t len) {
736 return meshlink_channel_send(handle, channel, data, len);
739 /// Get the amount of bytes in the send buffer.
740 /** This returns the amount of bytes in the send buffer.
741 * These bytes have not been received by the peer yet.
743 * @param channel A handle for the channel.
745 * @return The amount of un-ACKed bytes in the send buffer.
747 size_t channel_get_sendq(channel *channel) {
748 return meshlink_channel_get_sendq(handle, channel);
751 /// Get the amount of bytes in the receive buffer.
752 /** This returns the amount of bytes in the receive buffer.
753 * These bytes have not been processed by the application yet.
755 * @param channel A handle for the channel.
757 * @return The amount of bytes in the receive buffer.
759 size_t channel_get_recvq(channel *channel) {
760 return meshlink_channel_get_recvq(handle, channel);
763 /// Get the maximum segment size of a channel.
764 /** This returns the amount of bytes that can be sent at once for channels with UDP semantics.
766 * @param channel A handle for the channel.
768 * @return The amount of bytes in the receive buffer.
770 size_t channel_get_mss(channel *channel) {
771 return meshlink_channel_get_mss(handle, channel);
774 /// Inform MeshLink that the local network configuration might have changed
775 /** This is intended to be used when there is no way for MeshLink to get notifications of local network changes.
776 * It forces MeshLink to scan all network interfaces for changes in up/down status and new/removed addresses,
777 * and will immediately check if all connections to other nodes are still alive.
779 void hint_network_change() {
780 meshlink_hint_network_change(handle);
783 /// Set device class timeouts
784 /** This sets the ping interval and timeout for a given device class.
786 * @param devclass The device class to update
787 * @param pinginterval The interval between keepalive packets, in seconds. The default is 60.
788 * @param pingtimeout The required time within which a peer should respond, in seconds. The default is 5.
789 * The timeout must be smaller than the interval.
791 void set_dev_class_timeouts(dev_class_t devclass, int pinginterval, int pingtimeout) {
792 meshlink_set_dev_class_timeouts(handle, devclass, pinginterval, pingtimeout);
795 /// Set device class fast retry period
796 /** This sets the fast retry period for a given device class.
797 * During this period after the last time the mesh becomes unreachable, connections are tried once a second.
799 * @param devclass The device class to update
800 * @param fast_retry_period The period during which fast connection retries are done. The default is 0.
802 void set_dev_class_fast_retry_period(dev_class_t devclass, int fast_retry_period) {
803 meshlink_set_dev_class_fast_retry_period(handle, devclass, fast_retry_period);
806 /// Set device class maximum timeout
807 /** This sets the maximum timeout for outgoing connection retries for a given device class.
809 * @param devclass The device class to update
810 * @param maxtimeout The maximum timeout between reconnection attempts, in seconds. The default is 900.
812 void set_dev_class_maxtimeout(dev_class_t devclass, int maxtimeout) {
813 meshlink_set_dev_class_maxtimeout(handle, devclass, maxtimeout);
816 /// Set which order invitations are committed
817 /** This determines in which order configuration files are written to disk during an invitation.
818 * By default, the invitee saves the configuration to disk first, then the inviter.
819 * By calling this function with @a inviter_commits_first set to true, the order is reversed.
821 * @param inviter_commits_first If true, then the node that invited a peer will commit data to disk first.
823 void set_inviter_commits_first(bool inviter_commits_first) {
824 meshlink_set_inviter_commits_first(handle, inviter_commits_first);
829 mesh(const mesh &) /* TODO: C++11: = delete */;
830 void operator=(const mesh &) /* TODO: C++11: = delete */;
832 /// static callback trampolines:
833 static void receive_trampoline(meshlink_handle_t *handle, meshlink_node_t *source, const void *data, size_t length) {
834 if(!(handle->priv)) {
838 meshlink::mesh *that = static_cast<mesh *>(handle->priv);
839 that->receive(static_cast<node *>(source), data, length);
842 static void node_status_trampoline(meshlink_handle_t *handle, meshlink_node_t *peer, bool reachable) {
843 if(!(handle->priv)) {
847 meshlink::mesh *that = static_cast<mesh *>(handle->priv);
848 that->node_status(static_cast<node *>(peer), reachable);
851 static void node_duplicate_trampoline(meshlink_handle_t *handle, meshlink_node_t *peer) {
852 if(!(handle->priv)) {
856 meshlink::mesh *that = static_cast<mesh *>(handle->priv);
857 that->node_duplicate(static_cast<node *>(peer));
860 static void log_trampoline(meshlink_handle_t *handle, log_level_t level, const char *message) {
861 if(!(handle->priv)) {
865 meshlink::mesh *that = static_cast<mesh *>(handle->priv);
866 that->log(level, message);
869 static void error_trampoline(meshlink_handle_t *handle, meshlink_errno_t meshlink_errno) {
870 if(!(handle->priv)) {
874 meshlink::mesh *that = static_cast<mesh *>(handle->priv);
875 that->error(meshlink_errno);
878 static void connection_try_trampoline(meshlink_handle_t *handle, meshlink_node_t *peer) {
879 if(!(handle->priv)) {
883 meshlink::mesh *that = static_cast<mesh *>(handle->priv);
884 that->connection_try(static_cast<node *>(peer));
887 static bool channel_listen_trampoline(meshlink_handle_t *handle, meshlink_node_t *node, uint16_t port) {
888 if(!(handle->priv)) {
892 meshlink::mesh *that = static_cast<mesh *>(handle->priv);
893 return that->channel_listen(static_cast<meshlink::node *>(node), port);
896 static bool channel_accept_trampoline(meshlink_handle_t *handle, meshlink_channel *channel, uint16_t port, const void *data, size_t len) {
897 if(!(handle->priv)) {
901 meshlink::mesh *that = static_cast<mesh *>(handle->priv);
902 bool accepted = that->channel_accept(static_cast<meshlink::channel *>(channel), port, data, len);
905 meshlink_set_channel_receive_cb(handle, channel, &channel_receive_trampoline);
911 static void channel_receive_trampoline(meshlink_handle_t *handle, meshlink_channel *channel, const void *data, size_t len) {
912 if(!(handle->priv)) {
916 meshlink::mesh *that = static_cast<mesh *>(handle->priv);
917 that->channel_receive(static_cast<meshlink::channel *>(channel), data, len);
920 static void channel_poll_trampoline(meshlink_handle_t *handle, meshlink_channel *channel, size_t len) {
921 if(!(handle->priv)) {
925 meshlink::mesh *that = static_cast<mesh *>(handle->priv);
926 that->channel_poll(static_cast<meshlink::channel *>(channel), len);
929 meshlink_handle_t *handle;
932 static inline const char *strerror(errno_t err = meshlink_errno) {
933 return meshlink_strerror(err);
936 /// Destroy a MeshLink instance.
937 /** This function remove all configuration files of a MeshLink instance. It should only be called when the application
938 * does not have an open handle to this instance. Afterwards, a call to meshlink_open() will create a completely
941 * @param confbase The directory in which MeshLink stores its configuration files.
942 * After the function returns, the application is free to overwrite or free @a confbase @a.
944 * @return This function will return true if the MeshLink instance was successfully destroyed, false otherwise.
946 static inline bool destroy(const char *confbase) {
947 return meshlink_destroy(confbase);