1 /* Copyright (c) 2006-2022. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 #ifndef SIMGRID_S4U_MAILBOX_HPP
7 #define SIMGRID_S4U_MAILBOX_HPP
9 #include <simgrid/forward.h>
10 #include <simgrid/s4u/Actor.hpp>
11 #include <simgrid/s4u/Comm.hpp>
12 #include <smpi/forward.hpp>
13 #include <xbt/string.hpp>
21 /** @brief Mailboxes: Network rendez-vous points. */
22 class XBT_PUBLIC Mailbox {
26 friend kernel::activity::MailboxImpl;
29 kernel::activity::MailboxImpl* const pimpl_;
31 explicit Mailbox(kernel::activity::MailboxImpl * mbox) : pimpl_(mbox) {}
35 kernel::activity::MailboxImpl* get_impl() const { return pimpl_; }
38 /** @brief Retrieves the name of that mailbox as a C++ string */
39 const xbt::string& get_name() const;
40 /** @brief Retrieves the name of that mailbox as a C string */
41 const char* get_cname() const;
43 /** Retrieve the mailbox associated to the given name. Mailboxes are created on demand. */
44 static Mailbox* by_name(const std::string& name);
46 /** Returns whether the mailbox contains queued communications */
49 /* Returns the number of queued communications */
52 /** Check if there is a communication going on in a mailbox. */
55 /** Look if there is a communication going on in a mailbox and return the PID of the sender actor */
56 aid_t listen_from() const;
58 /** Check if there is a communication ready to be consumed from a mailbox. */
61 /** Gets the first element in the queue (without dequeuing it), or nullptr if none is there */
62 kernel::activity::CommImplPtr front() const;
64 /** Declare that the specified actor is a permanent receiver on that mailbox
66 * It means that the communications sent to this mailbox will start flowing to
67 * its host even before it does a get(). This models the real behavior of TCP
68 * and MPI communications, amongst other. It will improve the accuracy of
69 * predictions, in particular if your application exhibits swarms of small messages.
71 * SimGrid does not enforces any kind of ownership over the mailbox. Even if a receiver
72 * was declared, any other actors can still get() data from the mailbox. The timings
73 * will then probably be off tracks, so you should strive on your side to not get data
74 * from someone else's mailbox.
76 * Note that being permanent receivers of a mailbox prevents actors to be garbage-collected.
77 * If your simulation creates many short-lived actors that marked as permanent receiver, you
78 * should call mailbox->set_receiver(nullptr) by the end of the actors so that their memory gets
79 * properly reclaimed. This call should be at the end of the actor's function, not in an on_exit
82 void set_receiver(ActorPtr actor);
84 /** Return the actor declared as permanent receiver, or nullptr if none **/
85 ActorPtr get_receiver() const;
87 /** Creates (but don't start) a data transmission to that mailbox */
89 /** Creates (but don't start) a data transmission to that mailbox.
91 * Please note that if you send a pointer to some data, you must ensure that your data remains live during the
92 * communication, or the receiver will get a pointer to a garbled memory area.
94 CommPtr put_init(void* data, uint64_t simulated_size_in_bytes);
95 /** Creates and start a data transmission to that mailbox.
97 * Please note that if you send a pointer to some data, you must ensure that your data remains live during the
98 * communication, or the receiver will get a pointer to a garbled memory area.
100 CommPtr put_async(void* data, uint64_t simulated_size_in_bytes);
102 kernel::activity::ActivityImplPtr
103 iprobe(int type, const std::function<bool(void*, void*, kernel::activity::CommImpl*)>& match_fun, void* data);
104 /** Blocking data transmission.
106 * Please note that if you send a pointer to some data, you must ensure that your data remains live during the
107 * communication, or the receiver will get a pointer to a garbled memory area.
109 void put(void* payload, uint64_t simulated_size_in_bytes);
110 /** Blocking data transmission with timeout */
111 void put(void* payload, uint64_t simulated_size_in_bytes, double timeout);
113 /** Creates (but don't start) a data reception onto that mailbox.
114 * @verbatim embed:rst:inline You probably want to use :cpp:func:`simgrid::s4u::Comm::set_dst_data` and friends before
115 * starting that activity. @endverbatim */
117 /** Creates and start an async data reception to that mailbox */
118 template <typename T> CommPtr get_async(T** data);
120 /** Blocking data reception */
121 template <typename T> T* get();
122 template <typename T> std::unique_ptr<T> get_unique() { return std::unique_ptr<T>(get<T>()); }
124 /** Blocking data reception with timeout */
125 template <typename T> T* get(double timeout);
126 template <typename T> std::unique_ptr<T> get_unique(double timeout) { return std::unique_ptr<T>(get<T>(timeout)); }
131 template <typename T> CommPtr Mailbox::get_async(T** data)
133 CommPtr res = get_init()->set_dst_data(reinterpret_cast<void**>(data), sizeof(void*));
134 res->vetoable_start();
138 template <typename T> T* Mailbox::get()
141 get_async<T>(&res)->wait();
145 template <typename T> T* Mailbox::get(double timeout)
148 get_async<T>(&res)->wait_for(timeout);
152 } // namespace simgrid
154 #endif /* SIMGRID_S4U_MAILBOX_HPP */