From: Guus Sliepen Date: Tue, 10 Jun 2014 11:32:29 +0000 (+0200) Subject: Add a header-only C++ wrapper. X-Git-Url: http://git.meshlink.io/?p=meshlink;a=commitdiff_plain;h=0058ff2373221bf19a6cd30a853c3e8d696c2e74 Add a header-only C++ wrapper. --- diff --git a/src/meshlink++.h b/src/meshlink++.h new file mode 100644 index 00000000..3fa7774e --- /dev/null +++ b/src/meshlink++.h @@ -0,0 +1,297 @@ +/* + meshlink++.h -- MeshLink C++ API + Copyright (C) 2014 Guus Sliepen + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License along + with this program; if not, write to the Free Software Foundation, Inc., + 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. +*/ + +#ifndef MESHLINKPP_H +#define MESHLINKPP_H + +#include + +namespace meshlink { + class mesh; + class node; + + /// Severity of log messages generated by MeshLink. + typedef meshlink_log_level_t log_level_t; + + /// Code of most recent error encountered. + typedef meshlink_errno_t errno_t; + + /// A callback for receiving data from the mesh. + /** @param mesh A handle which represents an instance of MeshLink. + * @param source A pointer to a meshlink::node describing the source of the data. + * @param data A pointer to a buffer containing the data sent by the source. + * @param len The length of the received data. + */ + typedef void (*receive_cb_t)(mesh *mesh, node *source, const void *data, size_t len); + + /// A callback reporting node status changes. + /** @param mesh A handle which represents an instance of MeshLink. + * @param node A pointer to a meshlink::node describing the node whose status changed. + * @param reachable True if the node is reachable, false otherwise. + */ + typedef void (*node_status_cb_t)(mesh *mesh, node *node, bool reachable); + + /// A callback for receiving log messages generated by MeshLink. + /** @param mesh A handle which represents an instance of MeshLink. + * @param level An enum describing the severity level of the message. + * @param text A pointer to a string containing the textual log message. + */ + typedef void (*log_cb_t)(mesh *mesh, log_level_t level, const char *text); + + /// A class describing a MeshLink node. + class node: public meshlink_node_t { + }; + + /// A class describing a MeshLink mesh. + class mesh: public meshlink_handle_t { + public: + // TODO: delete constructor, add a destructor. + + /// Start MeshLink. + /** This function causes MeshLink to open network sockets, make outgoing connections, and + * create a new thread, which will handle all network I/O. + * + * @return This function will return true if MeshLink has succesfully started its thread, false otherwise. + */ + bool start() { + return meshlink_start(this); + } + + /// Stop MeshLink. + /** This function causes MeshLink to disconnect from all other nodes, + * close all sockets, and shut down its own thread. + */ + void stop() { + meshlink_stop(this); + } + + /// Set the receive callback. + /** This functions sets the callback that is called whenever another node sends data to the local node. + * The callback is run in MeshLink's own thread. + * It is therefore important that the callback uses apprioriate methods (queues, pipes, locking, etc.) + * to hand the data over to the application's thread. + * The callback should also not block itself and return as quickly as possible. + * + * @param cb A pointer to the function which will be called when another node sends data to the local node. + */ + void set_receive_cb(receive_cb_t cb) { + meshlink_set_receive_cb(this, (meshlink_receive_cb_t)cb); + } + + /// Set the node status callback. + /** This functions sets the callback that is called whenever another node's status changed. + * The callback is run in MeshLink's own thread. + * It is therefore important that the callback uses apprioriate methods (queues, pipes, locking, etc.) + * to hand the data over to the application's thread. + * The callback should also not block itself and return as quickly as possible. + * + * @param cb A pointer to the function which will be called when another node's status changes. + */ + void set_node_status_cb(node_status_cb_t cb) { + meshlink_set_node_status_cb(this, (meshlink_node_status_cb_t)cb); + } + + /// Set the log callback. + /** This functions sets the callback that is called whenever MeshLink has some information to log. + * The callback is run in MeshLink's own thread. + * It is important that the callback uses apprioriate methods (queues, pipes, locking, etc.) + * to hand the data over to the application's thread. + * The callback should also not block itself and return as quickly as possible. + * + * @param level An enum describing the minimum severity level. Debugging information with a lower level will not trigger the callback. + * @param cb A pointer to the function which will be called when another node sends data to the local node. + */ + void set_log_cb(meshlink_log_level_t level, log_cb_t cb) { + meshlink_set_log_cb(this, level, (meshlink_log_cb_t)cb); + } + + /// Send data to another node. + /** This functions sends one packet of data to another node in the mesh. + * The packet is sent using UDP semantics, which means that + * the packet is sent as one unit and is received as one unit, + * and that there is no guarantee that the packet will arrive at the destination. + * The application should take care of getting an acknowledgement and retransmission if necessary. + * + * @param destination A pointer to a meshlink::node describing the destination for the data. + * @param data A pointer to a buffer containing the data to be sent to the source. + * @param len The length of the data. + * @return This function will return true if MeshLink has queued the message for transmission, and false otherwise. + * A return value of true does not guarantee that the message will actually arrive at the destination. + */ + bool send(node *destination, const void *data, unsigned int len) { + return meshlink_send(this, destination, data, len); + } + + /// Get a handle for a specific node. + /** This function returns a handle for the node with the given name. + * + * @param name The name of the node for which a handle is requested. + * + * @return A pointer to a meshlink::node which represents the requested node, + * or NULL if the requested node does not exist. + */ + node *get_node(const char *name) { + return (node *)meshlink_get_node(this, name); + } + + /// Get a list of all nodes. + /** This function returns a list with handles for all known nodes. + * + * @param nodes A pointer to an array of pointers to meshlink::node, which should be allocated by the application. + * @param nmemb The maximum number of pointers that can be stored in the nodes array. + * + * @param return The number of known nodes. This can be larger than nmemb, in which case not all nodes were stored in the nodes array. + */ + size_t get_all_nodes(node **nodes, size_t nmemb) { + return meshlink_get_all_nodes(this, (meshlink_node_t **)nodes, nmemb); + } + + /// Sign data using the local node's MeshLink key. + /** This function signs data using the local node's MeshLink key. + * The generated signature can be securely verified by other nodes. + * + * @param data A pointer to a buffer containing the data to be signed. + * @param len The length of the data to be signed. + * + * @return This function returns a pointer to a string containing the signature, or NULL in case of an error. + * The application should call free() after it has finished using the signature. + */ + char *sign(const char *data, size_t len) { + return meshlink_sign(this, data, len); + } + + /// Verify the signature generated by another node of a piece of data. + /** This function verifies the signature that another node generated for a piece of data. + * + * @param source A pointer to a meshlink_node_t describing the source of the signature. + * @param data A pointer to a buffer containing the data to be verified. + * @param len The length of the data to be verified. + * @param signature A pointer to a string containing the signature. + * + * @return This function returns true if the signature is valid, false otherwise. + */ + bool verify(node *source, const char *data, size_t len, const char *signature) { + return meshlink_verify(this, source, data, len, signature); + } + + /// Add an Address for the local node. + /** This function adds an Address for the local node, which will be used for invitation URLs. + * + * @param address A string containing the address, which can be either in numeric format or a hostname. + * + * @return This function returns true if the address was added, false otherwise. + */ + bool add_address(const char *address) { + return meshlink_add_address(this, address); + } + + /// Invite another node into the mesh. + /** This function generates an invitation that can be used by another node to join the same mesh as the local node. + * The generated invitation is a string containing a URL. + * This URL should be passed by the application to the invitee in a way that no eavesdroppers can see the URL. + * The URL can only be used once, after the user has joined the mesh the URL is no longer valid. + * + * @param name The name that the invitee will use in the mesh. + * + * @return This function returns a string that contains the invitation URL. + * The application should call free() after it has finished using the URL. + */ + char *invite(const char *name) { + return meshlink_invite(this, name); + } + + /// Use an invitation to join a mesh. + /** This function allows the local node to join an existing mesh using an invitation URL generated by another node. + * An invitation can only be used if the local node has never connected to other nodes before. + * After a succesfully accepted invitation, the name of the local node may have changed. + * + * @param invitation A string containing the invitation URL. + * + * @return This function returns true if the local node joined the mesh it was invited to, false otherwise. + */ + bool join(const char *invitation) { + return meshlink_join(this, invitation); + } + + /// Export the local node's key and addresses. + /** This function generates a string that contains the local node's public key and one or more IP addresses. + * The application can pass it in some way to another node, which can then import it, + * granting the local node access to the other node's mesh. + * + * @return This function returns a string that contains the exported key and addresses. + * The application should call free() after it has finished using this string. + */ + char *export_key() { + return meshlink_export(this); + } + + /// Import another node's key and addresses. + /** This function accepts a string containing the exported public key and addresses of another node. + * By importing this data, the local node grants the other node access to its mesh. + * + * @param data A string containing the other node's exported key and addresses. + * + * @return This function returns true if the data was valid and the other node has been granted access to the mesh, false otherwise. + */ + bool import_key(const char *data) { + return meshlink_import(this, data); + } + + /// Blacklist a node from the mesh. + /** This function causes the local node to blacklist another node. + * The local node will drop any existing connections to that node, + * and will not send data to it nor accept any data received from it any more. + * + * @param node A pointer to a meshlink::node describing the node to be blacklisted. + */ + void blacklist(node *node) { + return meshlink_blacklist(this, node); + } + }; + + /// Initialize MeshLink's configuration directory. + /** This function causes MeshLink to initialize its configuration directory, + * if it hasn't already been initialized. + * It only has to be run the first time the application starts, + * but it is not a problem if it is run more than once, as long as + * the arguments given are the same. + * + * This function does not start any network I/O yet. The application should + * first set callbacks, and then call meshlink_start(). + * + * @param confbase The directory in which MeshLink will store its configuration files. + * @param name The name which this instance of the application will use in the mesh. + * + * @return This function will return a pointer to a meshlink::mesh if MeshLink has succesfully set up its configuration files, NULL otherwise. + */ + static mesh *open(const char *confbase, const char *name) { + return (mesh *)meshlink_open(confbase, name); + } + + /// Close the MeshLink handle. + /** This function calls meshlink_stop() if necessary, + * and frees all memory allocated by MeshLink. + * Afterwards, the handle and any pointers to a struct meshlink_node are invalid. + */ + static void close(mesh *mesh) { + meshlink_close(mesh); + } +}; + +#endif // MESHLINKPP_H