summaryrefslogtreecommitdiffstats
path: root/lib/isc/include/isc/socket.h
diff options
context:
space:
mode:
Diffstat (limited to 'lib/isc/include/isc/socket.h')
-rw-r--r--lib/isc/include/isc/socket.h914
1 files changed, 914 insertions, 0 deletions
diff --git a/lib/isc/include/isc/socket.h b/lib/isc/include/isc/socket.h
new file mode 100644
index 0000000..dc39a3f
--- /dev/null
+++ b/lib/isc/include/isc/socket.h
@@ -0,0 +1,914 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * 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 https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+#ifndef ISC_SOCKET_H
+#define ISC_SOCKET_H 1
+
+/*****
+***** Module Info
+*****/
+
+/*! \file isc/socket.h
+ * \brief Provides TCP and UDP sockets for network I/O. The sockets are event
+ * sources in the task system.
+ *
+ * When I/O completes, a completion event for the socket is posted to the
+ * event queue of the task which requested the I/O.
+ *
+ * \li MP:
+ * The module ensures appropriate synchronization of data structures it
+ * creates and manipulates.
+ * Clients of this module must not be holding a socket's task's lock when
+ * making a call that affects that socket. Failure to follow this rule
+ * can result in deadlock.
+ * The caller must ensure that isc_socketmgr_destroy() is called only
+ * once for a given manager.
+ *
+ * \li Reliability:
+ * No anticipated impact.
+ *
+ * \li Resources:
+ * TBS
+ *
+ * \li Security:
+ * No anticipated impact.
+ *
+ * \li Standards:
+ * None.
+ */
+
+/***
+ *** Imports
+ ***/
+
+#include <inttypes.h>
+#include <stdbool.h>
+
+#include <isc/event.h>
+#include <isc/eventclass.h>
+#include <isc/lang.h>
+#include <isc/region.h>
+#include <isc/sockaddr.h>
+#include <isc/time.h>
+#include <isc/types.h>
+
+ISC_LANG_BEGINDECLS
+
+/***
+ *** Constants
+ ***/
+
+/*%
+ * Maximum number of buffers in a scatter/gather read/write. The operating
+ * system in use must support at least this number (plus one on some.)
+ */
+#define ISC_SOCKET_MAXSCATTERGATHER 8
+
+/*@{*/
+/*!
+ * Socket options:
+ *
+ * _REUSEADDRESS: Set SO_REUSEADDR prior to calling bind(),
+ * if a non-zero port is specified (applies to
+ * AF_INET and AF_INET6).
+ */
+typedef enum {
+ ISC_SOCKET_REUSEADDRESS = 0x01U,
+} isc_socket_options_t;
+/*@}*/
+
+/*@{*/
+/*!
+ * _ATTACHED: Internal use only.
+ * _TRUNC: Packet was truncated on receive.
+ * _CTRUNC: Packet control information was truncated. This can
+ * indicate that the packet is not complete, even though
+ * all the data is valid.
+ * _TIMESTAMP: The timestamp member is valid.
+ * _PKTINFO: The pktinfo member is valid.
+ * _MULTICAST: The UDP packet was received via a multicast transmission.
+ * _DSCP: The UDP DSCP value is valid.
+ * _USEMINMTU: Set the per packet IPV6_USE_MIN_MTU flag.
+ */
+typedef enum {
+ ISC_SOCKEVENTATTR_ATTACHED = 0x10000000U, /* internal */
+ ISC_SOCKEVENTATTR_TRUNC = 0x00800000U, /* public */
+ ISC_SOCKEVENTATTR_CTRUNC = 0x00400000U, /* public */
+ ISC_SOCKEVENTATTR_TIMESTAMP = 0x00200000U, /* public */
+ ISC_SOCKEVENTATTR_PKTINFO = 0x00100000U, /* public */
+ ISC_SOCKEVENTATTR_MULTICAST = 0x00080000U, /* public */
+ ISC_SOCKEVENTATTR_DSCP = 0x00040000U, /* public */
+ ISC_SOCKEVENTATTR_USEMINMTU = 0x00020000U /* public */
+} isc_sockeventattr_t;
+/*@}*/
+
+/***
+ *** Types
+ ***/
+
+struct isc_socketevent {
+ ISC_EVENT_COMMON(isc_socketevent_t);
+ isc_result_t result; /*%< OK, EOF, whatever else */
+ unsigned int minimum; /*%< minimum i/o for event */
+ unsigned int n; /*%< bytes read or written */
+ unsigned int offset; /*%< offset into buffer list */
+ isc_region_t region; /*%< for single-buffer i/o */
+ isc_sockaddr_t address; /*%< source address */
+ isc_time_t timestamp; /*%< timestamp of packet recv */
+ struct in6_pktinfo pktinfo; /*%< ipv6 pktinfo */
+ isc_sockeventattr_t attributes; /*%< see isc_sockeventattr_t
+ * enum */
+ isc_eventdestructor_t destroy; /*%< original destructor */
+ unsigned int dscp; /*%< UDP dscp value */
+};
+
+typedef struct isc_socket_newconnev isc_socket_newconnev_t;
+struct isc_socket_newconnev {
+ ISC_EVENT_COMMON(isc_socket_newconnev_t);
+ isc_socket_t *newsocket;
+ isc_result_t result; /*%< OK, EOF, whatever else */
+ isc_sockaddr_t address; /*%< source address */
+};
+
+typedef struct isc_socket_connev isc_socket_connev_t;
+struct isc_socket_connev {
+ ISC_EVENT_COMMON(isc_socket_connev_t);
+ isc_result_t result; /*%< OK, EOF, whatever else */
+};
+
+#define ISC_SOCKEVENT_ANYEVENT (0)
+#define ISC_SOCKEVENT_RECVDONE (ISC_EVENTCLASS_SOCKET + 1)
+#define ISC_SOCKEVENT_SENDDONE (ISC_EVENTCLASS_SOCKET + 2)
+#define ISC_SOCKEVENT_NEWCONN (ISC_EVENTCLASS_SOCKET + 3)
+#define ISC_SOCKEVENT_CONNECT (ISC_EVENTCLASS_SOCKET + 4)
+
+/*
+ * Internal events.
+ */
+#define ISC_SOCKEVENT_INTR (ISC_EVENTCLASS_SOCKET + 256)
+#define ISC_SOCKEVENT_INTW (ISC_EVENTCLASS_SOCKET + 257)
+
+typedef enum {
+ isc_sockettype_udp = 1,
+ isc_sockettype_tcp = 2,
+ isc_sockettype_unix = 3,
+ isc_sockettype_raw = 4
+} isc_sockettype_t;
+
+/*@{*/
+/*!
+ * How a socket should be shutdown in isc_socket_shutdown() calls.
+ */
+#define ISC_SOCKSHUT_RECV 0x00000001 /*%< close read side */
+#define ISC_SOCKSHUT_SEND 0x00000002 /*%< close write side */
+#define ISC_SOCKSHUT_ALL 0x00000003 /*%< close them all */
+/*@}*/
+
+/*@{*/
+/*!
+ * What I/O events to cancel in isc_socket_cancel() calls.
+ */
+#define ISC_SOCKCANCEL_RECV 0x00000001 /*%< cancel recv */
+#define ISC_SOCKCANCEL_SEND 0x00000002 /*%< cancel send */
+#define ISC_SOCKCANCEL_ACCEPT 0x00000004 /*%< cancel accept */
+#define ISC_SOCKCANCEL_CONNECT 0x00000008 /*%< cancel connect */
+#define ISC_SOCKCANCEL_ALL 0x0000000f /*%< cancel everything */
+/*@}*/
+
+/*@{*/
+/*!
+ * Flags for isc_socket_send() and isc_socket_recv() calls.
+ */
+#define ISC_SOCKFLAG_IMMEDIATE 0x00000001 /*%< send event only if needed */
+#define ISC_SOCKFLAG_NORETRY 0x00000002 /*%< drop failed UDP sends */
+/*@}*/
+
+/***
+ *** Socket and Socket Manager Functions
+ ***
+ *** Note: all Ensures conditions apply only if the result is success for
+ *** those functions which return an isc_result.
+ ***/
+
+isc_result_t
+isc_socket_create(isc_socketmgr_t *manager, int pf, isc_sockettype_t type,
+ isc_socket_t **socketp);
+/*%<
+ * Create a new 'type' socket managed by 'manager'.
+ *
+ * Note:
+ *
+ *\li 'pf' is the desired protocol family, e.g. PF_INET or PF_INET6.
+ *
+ * Requires:
+ *
+ *\li 'manager' is a valid manager
+ *
+ *\li 'socketp' is a valid pointer, and *socketp == NULL
+ *
+ * Ensures:
+ *
+ * '*socketp' is attached to the newly created socket
+ *
+ * Returns:
+ *
+ *\li #ISC_R_SUCCESS
+ *\li #ISC_R_NOMEMORY
+ *\li #ISC_R_NORESOURCES
+ *\li #ISC_R_UNEXPECTED
+ */
+
+isc_result_t
+isc_socket_dup(isc_socket_t *sock0, isc_socket_t **socketp);
+/*%<
+ * Duplicate an existing socket, reusing its file descriptor.
+ */
+
+void
+isc_socket_cancel(isc_socket_t *sock, isc_task_t *task, unsigned int how);
+/*%<
+ * Cancel pending I/O of the type specified by "how".
+ *
+ * Note: if "task" is NULL, then the cancel applies to all tasks using the
+ * socket.
+ *
+ * Requires:
+ *
+ * \li "socket" is a valid socket
+ *
+ * \li "task" is NULL or a valid task
+ *
+ * "how" is a bitmask describing the type of cancellation to perform.
+ * The type ISC_SOCKCANCEL_ALL will cancel all pending I/O on this
+ * socket.
+ *
+ * \li ISC_SOCKCANCEL_RECV:
+ * Cancel pending isc_socket_recv() calls.
+ *
+ * \li ISC_SOCKCANCEL_SEND:
+ * Cancel pending isc_socket_send() and isc_socket_sendto() calls.
+ *
+ * \li ISC_SOCKCANCEL_ACCEPT:
+ * Cancel pending isc_socket_accept() calls.
+ *
+ * \li ISC_SOCKCANCEL_CONNECT:
+ * Cancel pending isc_socket_connect() call.
+ */
+
+void
+isc_socket_shutdown(isc_socket_t *sock, unsigned int how);
+/*%<
+ * Shutdown 'socket' according to 'how'.
+ *
+ * Requires:
+ *
+ * \li 'socket' is a valid socket.
+ *
+ * \li 'task' is NULL or is a valid task.
+ *
+ * \li If 'how' is 'ISC_SOCKSHUT_RECV' or 'ISC_SOCKSHUT_ALL' then
+ *
+ * The read queue must be empty.
+ *
+ * No further read requests may be made.
+ *
+ * \li If 'how' is 'ISC_SOCKSHUT_SEND' or 'ISC_SOCKSHUT_ALL' then
+ *
+ * The write queue must be empty.
+ *
+ * No further write requests may be made.
+ */
+
+void
+isc_socket_attach(isc_socket_t *sock, isc_socket_t **socketp);
+/*%<
+ * Attach *socketp to socket.
+ *
+ * Requires:
+ *
+ * \li 'socket' is a valid socket.
+ *
+ * \li 'socketp' points to a NULL socket.
+ *
+ * Ensures:
+ *
+ * \li *socketp is attached to socket.
+ */
+
+void
+isc_socket_detach(isc_socket_t **socketp);
+/*%<
+ * Detach *socketp from its socket.
+ *
+ * Requires:
+ *
+ * \li 'socketp' points to a valid socket.
+ *
+ * \li If '*socketp' is the last reference to the socket,
+ * then:
+ *
+ * There must be no pending I/O requests.
+ *
+ * Ensures:
+ *
+ * \li *socketp is NULL.
+ *
+ * \li If '*socketp' is the last reference to the socket,
+ * then:
+ *
+ * The socket will be shutdown (both reading and writing)
+ * for all tasks.
+ *
+ * All resources used by the socket have been freed
+ */
+
+isc_result_t
+isc_socket_open(isc_socket_t *sock);
+/*%<
+ * Open a new socket file descriptor of the given socket structure. It simply
+ * opens a new descriptor; all of the other parameters including the socket
+ * type are inherited from the existing socket. This function is provided to
+ * avoid overhead of destroying and creating sockets when many short-lived
+ * sockets are frequently opened and closed. When the efficiency is not an
+ * issue, it should be safer to detach the unused socket and re-create a new
+ * one. This optimization may not be available for some systems, in which
+ * case this function will return ISC_R_NOTIMPLEMENTED and must not be used.
+ *
+ * Requires:
+ *
+ * \li there must be no other reference to this socket.
+ *
+ * \li 'socket' is a valid and previously closed by isc_socket_close()
+ *
+ * Returns:
+ * Same as isc_socket_create().
+ * \li ISC_R_NOTIMPLEMENTED
+ */
+
+isc_result_t
+isc_socket_close(isc_socket_t *sock);
+/*%<
+ * Close a socket file descriptor of the given socket structure. This function
+ * is provided as an alternative to destroying an unused socket when overhead
+ * destroying/re-creating sockets can be significant, and is expected to be
+ * used with isc_socket_open(). This optimization may not be available for some
+ * systems, in which case this function will return ISC_R_NOTIMPLEMENTED and
+ * must not be used.
+ *
+ * Requires:
+ *
+ * \li The socket must have a valid descriptor.
+ *
+ * \li There must be no other reference to this socket.
+ *
+ * \li There must be no pending I/O requests.
+ *
+ * Returns:
+ * \li #ISC_R_NOTIMPLEMENTED
+ */
+
+isc_result_t
+isc_socket_bind(isc_socket_t *sock, const isc_sockaddr_t *addressp,
+ isc_socket_options_t options);
+/*%<
+ * Bind 'socket' to '*addressp'.
+ *
+ * Requires:
+ *
+ * \li 'socket' is a valid socket
+ *
+ * \li 'addressp' points to a valid isc_sockaddr.
+ *
+ * Returns:
+ *
+ * \li ISC_R_SUCCESS
+ * \li ISC_R_NOPERM
+ * \li ISC_R_ADDRNOTAVAIL
+ * \li ISC_R_ADDRINUSE
+ * \li ISC_R_BOUND
+ * \li ISC_R_UNEXPECTED
+ */
+
+isc_result_t
+isc_socket_filter(isc_socket_t *sock, const char *filter);
+/*%<
+ * Inform the kernel that it should perform accept filtering.
+ * If filter is NULL the current filter will be removed.
+ */
+
+isc_result_t
+isc_socket_listen(isc_socket_t *sock, unsigned int backlog);
+/*%<
+ * Set listen mode on the socket. After this call, the only function that
+ * can be used (other than attach and detach) is isc_socket_accept().
+ *
+ * Notes:
+ *
+ * \li 'backlog' is as in the UNIX system call listen() and may be
+ * ignored by non-UNIX implementations.
+ *
+ * \li If 'backlog' is zero, a reasonable system default is used, usually
+ * SOMAXCONN.
+ *
+ * Requires:
+ *
+ * \li 'socket' is a valid, bound TCP socket or a valid, bound UNIX socket.
+ *
+ * Returns:
+ *
+ * \li ISC_R_SUCCESS
+ * \li ISC_R_UNEXPECTED
+ */
+
+isc_result_t
+isc_socket_accept(isc_socket_t *sock, isc_task_t *task, isc_taskaction_t action,
+ void *arg);
+/*%<
+ * Queue accept event. When a new connection is received, the task will
+ * get an ISC_SOCKEVENT_NEWCONN event with the sender set to the listen
+ * socket. The new socket structure is sent inside the isc_socket_newconnev_t
+ * event type, and is attached to the task 'task'.
+ *
+ * REQUIRES:
+ * \li 'socket' is a valid TCP socket that isc_socket_listen() was called
+ * on.
+ *
+ * \li 'task' is a valid task
+ *
+ * \li 'action' is a valid action
+ *
+ * RETURNS:
+ * \li ISC_R_SUCCESS
+ * \li ISC_R_NOMEMORY
+ * \li ISC_R_UNEXPECTED
+ */
+
+isc_result_t
+isc_socket_connect(isc_socket_t *sock, const isc_sockaddr_t *addressp,
+ isc_task_t *task, isc_taskaction_t action, void *arg);
+/*%<
+ * Connect 'socket' to peer with address *saddr. When the connection
+ * succeeds, or when an error occurs, a CONNECT event with action 'action'
+ * and arg 'arg' will be posted to the event queue for 'task'.
+ *
+ * Requires:
+ *
+ * \li 'socket' is a valid TCP socket
+ *
+ * \li 'addressp' points to a valid isc_sockaddr
+ *
+ * \li 'task' is a valid task
+ *
+ * \li 'action' is a valid action
+ *
+ * Returns:
+ *
+ * \li ISC_R_SUCCESS
+ * \li ISC_R_NOMEMORY
+ * \li ISC_R_UNEXPECTED
+ *
+ * Posted event's result code:
+ *
+ * \li ISC_R_SUCCESS
+ * \li ISC_R_TIMEDOUT
+ * \li ISC_R_CONNREFUSED
+ * \li ISC_R_NETUNREACH
+ * \li ISC_R_UNEXPECTED
+ */
+
+isc_result_t
+isc_socket_getpeername(isc_socket_t *sock, isc_sockaddr_t *addressp);
+/*%<
+ * Get the name of the peer connected to 'socket'.
+ *
+ * Requires:
+ *
+ * \li 'socket' is a valid TCP socket.
+ *
+ * Returns:
+ *
+ * \li ISC_R_SUCCESS
+ * \li ISC_R_TOOSMALL
+ * \li ISC_R_UNEXPECTED
+ */
+
+isc_result_t
+isc_socket_getsockname(isc_socket_t *sock, isc_sockaddr_t *addressp);
+/*%<
+ * Get the name of 'socket'.
+ *
+ * Requires:
+ *
+ * \li 'socket' is a valid socket.
+ *
+ * Returns:
+ *
+ * \li ISC_R_SUCCESS
+ * \li ISC_R_TOOSMALL
+ * \li ISC_R_UNEXPECTED
+ */
+
+/*@{*/
+isc_result_t
+isc_socket_recv(isc_socket_t *sock, isc_region_t *region, unsigned int minimum,
+ isc_task_t *task, isc_taskaction_t action, void *arg);
+
+isc_result_t
+isc_socket_recv2(isc_socket_t *sock, isc_region_t *region, unsigned int minimum,
+ isc_task_t *task, isc_socketevent_t *event,
+ unsigned int flags);
+
+/*!
+ * Receive from 'socket', storing the results in region.
+ *
+ * Notes:
+ *
+ *\li Let 'length' refer to the length of 'region' or to the sum of all
+ * available regions in the list of buffers '*buflist'.
+ *
+ *\li If 'minimum' is non-zero and at least that many bytes are read,
+ * the completion event will be posted to the task 'task.' If minimum
+ * is zero, the exact number of bytes requested in the region must
+ * be read for an event to be posted. This only makes sense for TCP
+ * connections, and is always set to 1 byte for UDP.
+ *
+ *\li The read will complete when the desired number of bytes have been
+ * read, if end-of-input occurs, or if an error occurs. A read done
+ * event with the given 'action' and 'arg' will be posted to the
+ * event queue of 'task'.
+ *
+ *\li The caller may not modify 'region', the buffers which are passed
+ * into this function, or any data they refer to until the completion
+ * event is received.
+ *
+ *\li For isc_socket_recv2():
+ * 'event' is not NULL, and the non-socket specific fields are
+ * expected to be initialized.
+ *
+ *\li For isc_socket_recv2():
+ * The only defined value for 'flags' is ISC_SOCKFLAG_IMMEDIATE. If
+ * set and the operation completes, the return value will be
+ * ISC_R_SUCCESS and the event will be filled in and not sent. If the
+ * operation does not complete, the return value will be
+ * ISC_R_INPROGRESS and the event will be sent when the operation
+ * completes.
+ *
+ * Requires:
+ *
+ *\li 'socket' is a valid, bound socket.
+ *
+ *\li For isc_socket_recv():
+ * 'region' is a valid region
+ *
+ *\li For isc_socket_recvv():
+ * 'buflist' is non-NULL, and '*buflist' contain at least one buffer.
+ *
+ *\li 'task' is a valid task
+ *
+ *\li For isc_socket_recv() and isc_socket_recvv():
+ * action != NULL and is a valid action
+ *
+ *\li For isc_socket_recv2():
+ * event != NULL
+ *
+ * Returns:
+ *
+ *\li #ISC_R_SUCCESS
+ *\li #ISC_R_INPROGRESS
+ *\li #ISC_R_NOMEMORY
+ *\li #ISC_R_UNEXPECTED
+ *
+ * Event results:
+ *
+ *\li #ISC_R_SUCCESS
+ *\li #ISC_R_UNEXPECTED
+ *\li XXX needs other net-type errors
+ */
+/*@}*/
+
+/*@{*/
+isc_result_t
+isc_socket_send(isc_socket_t *sock, isc_region_t *region, isc_task_t *task,
+ isc_taskaction_t action, void *arg);
+isc_result_t
+isc_socket_sendto(isc_socket_t *sock, isc_region_t *region, isc_task_t *task,
+ isc_taskaction_t action, void *arg,
+ const isc_sockaddr_t *address, struct in6_pktinfo *pktinfo);
+isc_result_t
+isc_socket_sendto2(isc_socket_t *sock, isc_region_t *region, isc_task_t *task,
+ const isc_sockaddr_t *address, struct in6_pktinfo *pktinfo,
+ isc_socketevent_t *event, unsigned int flags);
+
+/*!
+ * Send the contents of 'region' to the socket's peer.
+ *
+ * Notes:
+ *
+ *\li Shutting down the requestor's task *may* result in any
+ * still pending writes being dropped or completed, depending on the
+ * underlying OS implementation.
+ *
+ *\li If 'action' is NULL, then no completion event will be posted.
+ *
+ *\li The caller may not modify 'region', the buffers which are passed
+ * into this function, or any data they refer to until the completion
+ * event is received.
+ *
+ *\li For isc_socket_sendto2():
+ * 'event' is not NULL, and the non-socket specific fields are
+ * expected to be initialized.
+ *
+ *\li For isc_socket_sendto2():
+ * The only defined values for 'flags' are ISC_SOCKFLAG_IMMEDIATE
+ * and ISC_SOCKFLAG_NORETRY.
+ *
+ *\li If ISC_SOCKFLAG_IMMEDIATE is set and the operation completes, the
+ * return value will be ISC_R_SUCCESS and the event will be filled
+ * in and not sent. If the operation does not complete, the return
+ * value will be ISC_R_INPROGRESS and the event will be sent when
+ * the operation completes.
+ *
+ *\li ISC_SOCKFLAG_NORETRY can only be set for UDP sockets. If set
+ * and the send operation fails due to a transient error, the send
+ * will not be retried and the error will be indicated in the event.
+ * Using this option along with ISC_SOCKFLAG_IMMEDIATE allows the caller
+ * to specify a region that is allocated on the stack.
+ *
+ * Requires:
+ *
+ *\li 'socket' is a valid, bound socket.
+ *
+ *\li For isc_socket_send():
+ * 'region' is a valid region
+ *
+ *\li For isc_socket_sendv() and isc_socket_sendtov():
+ * 'buflist' is non-NULL, and '*buflist' contain at least one buffer.
+ *
+ *\li 'task' is a valid task
+ *
+ *\li For isc_socket_sendv(), isc_socket_sendtov(), isc_socket_send(), and
+ * isc_socket_sendto():
+ * action == NULL or is a valid action
+ *
+ *\li For isc_socket_sendto2():
+ * event != NULL
+ *
+ * Returns:
+ *
+ *\li #ISC_R_SUCCESS
+ *\li #ISC_R_INPROGRESS
+ *\li #ISC_R_NOMEMORY
+ *\li #ISC_R_UNEXPECTED
+ *
+ * Event results:
+ *
+ *\li #ISC_R_SUCCESS
+ *\li #ISC_R_UNEXPECTED
+ *\li XXX needs other net-type errors
+ */
+/*@}*/
+
+isc_result_t
+isc_socketmgr_create(isc_mem_t *mctx, isc_socketmgr_t **managerp);
+
+isc_result_t
+isc_socketmgr_create2(isc_mem_t *mctx, isc_socketmgr_t **managerp,
+ unsigned int maxsocks, int nthreads);
+/*%<
+ * Create a socket manager. If "maxsocks" is non-zero, it specifies the
+ * maximum number of sockets that the created manager should handle.
+ * isc_socketmgr_create() is equivalent of isc_socketmgr_create2() with
+ * "maxsocks" being zero.
+ *
+ * Notes:
+ *
+ *\li All memory will be allocated in memory context 'mctx'.
+ *
+ * Requires:
+ *
+ *\li 'mctx' is a valid memory context.
+ *
+ *\li 'managerp' points to a NULL isc_socketmgr_t.
+ *
+ *\li 'actx' is a valid application context (for createinctx()).
+ *
+ * Ensures:
+ *
+ *\li '*managerp' is a valid isc_socketmgr_t.
+ *
+ * Returns:
+ *
+ *\li #ISC_R_SUCCESS
+ *\li #ISC_R_NOMEMORY
+ *\li #ISC_R_UNEXPECTED
+ *\li #ISC_R_NOTIMPLEMENTED
+ */
+
+isc_result_t
+isc_socketmgr_getmaxsockets(isc_socketmgr_t *manager, unsigned int *nsockp);
+/*%<
+ * Returns in "*nsockp" the maximum number of sockets this manager may open.
+ *
+ * Requires:
+ *
+ *\li '*manager' is a valid isc_socketmgr_t.
+ *\li 'nsockp' is not NULL.
+ *
+ * Returns:
+ *
+ *\li #ISC_R_SUCCESS
+ *\li #ISC_R_NOTIMPLEMENTED
+ */
+
+void
+isc_socketmgr_setstats(isc_socketmgr_t *manager, isc_stats_t *stats);
+/*%<
+ * Set a general socket statistics counter set 'stats' for 'manager'.
+ *
+ * Requires:
+ * \li 'manager' is valid, hasn't opened any socket, and doesn't have
+ * stats already set.
+ *
+ *\li stats is a valid statistics supporting socket statistics counters
+ * (see above).
+ */
+
+void
+isc_socketmgr_destroy(isc_socketmgr_t **managerp);
+/*%<
+ * Destroy a socket manager.
+ *
+ * Notes:
+ *
+ *\li This routine blocks until there are no sockets left in the manager,
+ * so if the caller holds any socket references using the manager, it
+ * must detach them before calling isc_socketmgr_destroy() or it will
+ * block forever.
+ *
+ * Requires:
+ *
+ *\li '*managerp' is a valid isc_socketmgr_t.
+ *
+ *\li All sockets managed by this manager are fully detached.
+ *
+ * Ensures:
+ *
+ *\li *managerp == NULL
+ *
+ *\li All resources used by the manager have been freed.
+ */
+
+isc_sockettype_t
+isc_socket_gettype(isc_socket_t *sock);
+/*%<
+ * Returns the socket type for "sock."
+ *
+ * Requires:
+ *
+ *\li "sock" is a valid socket.
+ */
+
+/*@{*/
+void
+isc_socket_ipv6only(isc_socket_t *sock, bool yes);
+/*%<
+ * If the socket is an IPv6 socket set/clear the IPV6_IPV6ONLY socket
+ * option if the host OS supports this option.
+ *
+ * Requires:
+ *\li 'sock' is a valid socket.
+ */
+/*@}*/
+
+void
+isc_socket_dscp(isc_socket_t *sock, isc_dscp_t dscp);
+/*%<
+ * Sets the Differentiated Services Code Point (DSCP) field for packets
+ * transmitted on this socket. If 'dscp' is -1, return immediately.
+ *
+ * Requires:
+ *\li 'sock' is a valid socket.
+ */
+
+isc_socketevent_t *
+isc_socket_socketevent(isc_mem_t *mctx, void *sender, isc_eventtype_t eventtype,
+ isc_taskaction_t action, void *arg);
+/*%<
+ * Get a isc_socketevent_t to be used with isc_socket_sendto2(), etc.
+ */
+
+void
+isc_socket_cleanunix(const isc_sockaddr_t *addr, bool active);
+
+/*%<
+ * Cleanup UNIX domain sockets in the file-system. If 'active' is true
+ * then just unlink the socket. If 'active' is false try to determine
+ * if there is a listener of the socket or not. If no listener is found
+ * then unlink socket.
+ *
+ * Prior to unlinking the path is tested to see if it a socket.
+ *
+ * Note: there are a number of race conditions which cannot be avoided
+ * both in the filesystem and any application using UNIX domain
+ * sockets (e.g. socket is tested between bind() and listen(),
+ * the socket is deleted and replaced in the file-system between
+ * stat() and unlink()).
+ */
+
+isc_result_t
+isc_socket_permunix(const isc_sockaddr_t *sockaddr, uint32_t perm,
+ uint32_t owner, uint32_t group);
+/*%<
+ * Set ownership and file permissions on the UNIX domain socket.
+ *
+ * Note: On Solaris this secures the directory containing
+ * the socket as Solaris do not honour the filesystem
+ * permissions on the socket.
+ *
+ * Requires:
+ * \li 'sockaddr' to be a valid UNIX domain sockaddr.
+ *
+ * Returns:
+ * \li #ISC_R_SUCCESS
+ * \li #ISC_R_FAILURE
+ */
+
+void
+isc_socket_setname(isc_socket_t *socket, const char *name, void *tag);
+/*%<
+ * Set the name and optional tag for a socket. This allows tracking of the
+ * owner or purpose for this socket, and is useful for tracing and statistics
+ * reporting.
+ */
+
+const char *
+isc_socket_getname(isc_socket_t *socket);
+/*%<
+ * Get the name associated with a socket, if any.
+ */
+
+void *
+isc_socket_gettag(isc_socket_t *socket);
+/*%<
+ * Get the tag associated with a socket, if any.
+ */
+
+int
+isc_socket_getfd(isc_socket_t *socket);
+/*%<
+ * Get the file descriptor associated with a socket
+ */
+
+void
+isc_socketmgr_setreserved(isc_socketmgr_t *mgr, uint32_t);
+/*%<
+ * Temporary. For use by named only.
+ */
+
+void
+isc_socketmgr_maxudp(isc_socketmgr_t *mgr, unsigned int maxudp);
+/*%<
+ * Test interface. Drop UDP packet > 'maxudp'.
+ */
+
+bool
+isc_socket_hasreuseport(void);
+/*%<
+ * Return true if there is SO_REUSEPORT support
+ */
+
+#ifdef HAVE_LIBXML2
+int
+isc_socketmgr_renderxml(isc_socketmgr_t *mgr, void *writer0);
+/*%<
+ * Render internal statistics and other state into the XML document.
+ */
+#endif /* HAVE_LIBXML2 */
+
+#ifdef HAVE_JSON_C
+isc_result_t
+isc_socketmgr_renderjson(isc_socketmgr_t *mgr, void *stats0);
+/*%<
+ * Render internal statistics and other state into JSON format.
+ */
+#endif /* HAVE_JSON_C */
+
+/*%<
+ * See isc_socketmgr_create() above.
+ */
+typedef isc_result_t (*isc_socketmgrcreatefunc_t)(isc_mem_t *mctx,
+ isc_socketmgr_t **managerp);
+
+ISC_LANG_ENDDECLS
+
+#endif /* ISC_SOCKET_H */