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/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef APR_POLL_H
#define APR_POLL_H
/**
* @file apr_poll.h
* @brief APR Poll interface
*/
#include "apr.h"
#include "apr_pools.h"
#include "apr_errno.h"
#include "apr_inherit.h"
#include "apr_file_io.h"
#include "apr_network_io.h"
#if APR_HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#ifdef __cplusplus
extern "C" {
#endif /* __cplusplus */
/**
* @defgroup apr_poll Poll Routines
* @ingroup APR
* @{
*/
/**
* Poll options
*/
#define APR_POLLIN 0x001 /**< Can read without blocking */
#define APR_POLLPRI 0x002 /**< Priority data available */
#define APR_POLLOUT 0x004 /**< Can write without blocking */
#define APR_POLLERR 0x010 /**< Pending error */
#define APR_POLLHUP 0x020 /**< Hangup occurred */
#define APR_POLLNVAL 0x040 /**< Descriptior invalid */
/**
* Pollset Flags
*/
#define APR_POLLSET_THREADSAFE 0x001 /**< Adding or Removing a Descriptor is thread safe */
#define APR_POLLSET_NOCOPY 0x002 /**< Descriptors passed to apr_pollset_create() are not copied */
/** Used in apr_pollfd_t to determine what the apr_descriptor is */
typedef enum {
APR_NO_DESC, /**< nothing here */
APR_POLL_SOCKET, /**< descriptor refers to a socket */
APR_POLL_FILE, /**< descriptor refers to a file */
APR_POLL_LASTDESC /**< @deprecated descriptor is the last one in the list */
} apr_datatype_e ;
/** Union of either an APR file or socket. */
typedef union {
apr_file_t *f; /**< file */
apr_socket_t *s; /**< socket */
} apr_descriptor;
/** @see apr_pollfd_t */
typedef struct apr_pollfd_t apr_pollfd_t;
/** Poll descriptor set. */
struct apr_pollfd_t {
apr_pool_t *p; /**< associated pool */
apr_datatype_e desc_type; /**< descriptor type */
apr_int16_t reqevents; /**< requested events */
apr_int16_t rtnevents; /**< returned events */
apr_descriptor desc; /**< @see apr_descriptor */
void *client_data; /**< allows app to associate context */
};
/* General-purpose poll API for arbitrarily large numbers of
* file descriptors
*/
/** Opaque structure used for pollset API */
typedef struct apr_pollset_t apr_pollset_t;
/**
* Setup a pollset object
* @param pollset The pointer in which to return the newly created object
* @param size The maximum number of descriptors that this pollset can hold
* @param p The pool from which to allocate the pollset
* @param flags Optional flags to modify the operation of the pollset.
*
* @remark If flags equals APR_POLLSET_THREADSAFE, then a pollset is
* created on which it is safe to make concurrent calls to
* apr_pollset_add(), apr_pollset_remove() and apr_pollset_poll() from
* separate threads. This feature is only supported on some
* platforms; the apr_pollset_create() call will fail with
* APR_ENOTIMPL on platforms where it is not supported.
*/
APR_DECLARE(apr_status_t) apr_pollset_create(apr_pollset_t **pollset,
apr_uint32_t size,
apr_pool_t *p,
apr_uint32_t flags);
/**
* Destroy a pollset object
* @param pollset The pollset to destroy
*/
APR_DECLARE(apr_status_t) apr_pollset_destroy(apr_pollset_t *pollset);
/**
* Add a socket or file descriptor to a pollset
* @param pollset The pollset to which to add the descriptor
* @param descriptor The descriptor to add
* @remark If you set client_data in the descriptor, that value
* will be returned in the client_data field whenever this
* descriptor is signalled in apr_pollset_poll().
* @remark If the pollset has been created with APR_POLLSET_THREADSAFE
* and thread T1 is blocked in a call to apr_pollset_poll() for
* this same pollset that is being modified via apr_pollset_add()
* in thread T2, the currently executing apr_pollset_poll() call in
* T1 will either: (1) automatically include the newly added descriptor
* in the set of descriptors it is watching or (2) return immediately
* with APR_EINTR. Option (1) is recommended, but option (2) is
* allowed for implementations where option (1) is impossible
* or impractical.
*/
APR_DECLARE(apr_status_t) apr_pollset_add(apr_pollset_t *pollset,
const apr_pollfd_t *descriptor);
/**
* Remove a descriptor from a pollset
* @param pollset The pollset from which to remove the descriptor
* @param descriptor The descriptor to remove
* @remark If the pollset has been created with APR_POLLSET_THREADSAFE
* and thread T1 is blocked in a call to apr_pollset_poll() for
* this same pollset that is being modified via apr_pollset_remove()
* in thread T2, the currently executing apr_pollset_poll() call in
* T1 will either: (1) automatically exclude the newly added descriptor
* in the set of descriptors it is watching or (2) return immediately
* with APR_EINTR. Option (1) is recommended, but option (2) is
* allowed for implementations where option (1) is impossible
* or impractical.
*/
APR_DECLARE(apr_status_t) apr_pollset_remove(apr_pollset_t *pollset,
const apr_pollfd_t *descriptor);
/**
* Block for activity on the descriptor(s) in a pollset
* @param pollset The pollset to use
* @param timeout The amount of time in microseconds to wait. This is
* a maximum, not a minimum. If a descriptor is signalled, we
* will wake up before this time. A negative number means
* wait until a descriptor is signalled.
* @param num Number of signalled descriptors (output parameter)
* @param descriptors Array of signalled descriptors (output parameter)
*/
APR_DECLARE(apr_status_t) apr_pollset_poll(apr_pollset_t *pollset,
apr_interval_time_t timeout,
apr_int32_t *num,
const apr_pollfd_t **descriptors);
/**
* Poll the descriptors in the poll structure
* @param aprset The poll structure we will be using.
* @param numsock The number of descriptors we are polling
* @param nsds The number of descriptors signalled (output parameter)
* @param timeout The amount of time in microseconds to wait. This is
* a maximum, not a minimum. If a descriptor is signalled, we
* will wake up before this time. A negative number means
* wait until a descriptor is signalled.
* @remark The number of descriptors signalled is returned in the third argument.
* This is a blocking call, and it will not return until either a
* descriptor has been signalled, or the timeout has expired.
* @remark The rtnevents field in the apr_pollfd_t array will only be filled-
* in if the return value is APR_SUCCESS.
*/
APR_DECLARE(apr_status_t) apr_poll(apr_pollfd_t *aprset, apr_int32_t numsock,
apr_int32_t *nsds,
apr_interval_time_t timeout);
/** Opaque structure used for pollset API */
typedef struct apr_pollcb_t apr_pollcb_t;
/**
* Setup a pollcb object
* @param pollcb The pointer in which to return the newly created object
* @param size The maximum number of descriptors that a single _poll can return.
* @param p The pool from which to allocate the pollcb
* @param flags Optional flags to modify the operation of the pollcb.
*
* @remark Pollcb is only supported on some platforms; the apr_pollcb_create()
* call will fail with APR_ENOTIMPL on platforms where it is not supported.
*/
APR_DECLARE(apr_status_t) apr_pollcb_create(apr_pollcb_t **pollcb,
apr_uint32_t size,
apr_pool_t *pool,
apr_uint32_t flags);
/**
* Add a socket or file descriptor to a pollcb
* @param pollcb The pollcb to which to add the descriptor
* @param descriptor The descriptor to add
* @remark If you set client_data in the descriptor, that value
* will be returned in the client_data field whenever this
* descriptor is signalled in apr_pollcb_poll().
* @remark Unlike the apr_pollset API, the descriptor is not copied, and users
* must retain the memory used by descriptor, as the same pointer will be
* returned to them from apr_pollcb_poll.
*/
APR_DECLARE(apr_status_t) apr_pollcb_add(apr_pollcb_t *pollcb,
apr_pollfd_t *descriptor);
/**
* Remove a descriptor from a pollcb
* @param pollcb The pollcb from which to remove the descriptor
* @param descriptor The descriptor to remove
*/
APR_DECLARE(apr_status_t) apr_pollcb_remove(apr_pollcb_t *pollcb,
apr_pollfd_t *descriptor);
/** Function prototype for pollcb handlers
* @param baton Opaque baton passed into apr_pollcb_poll
* @param descriptor Contains the notification for an active descriptor,
* the rtnevents member contains what events were triggered
* for this descriptor.
*/
typedef apr_status_t (*apr_pollcb_cb_t)(void *baton, apr_pollfd_t *descriptor);
/**
* Block for activity on the descriptor(s) in a pollcb
* @param pollcb The pollcb to use
* @param timeout The amount of time in microseconds to wait. This is
* a maximum, not a minimum. If a descriptor is signalled, we
* will wake up before this time. A negative number means
* wait until a descriptor is signalled.
* @param func Callback function to call for each active socket
* @param baton Opaque baton passed to the callback function.
*/
APR_DECLARE(apr_status_t) apr_pollcb_poll(apr_pollcb_t *pollcb,
apr_interval_time_t timeout,
apr_pollcb_cb_t func,
void *baton);
/** @} */
#ifdef __cplusplus
}
#endif
#endif /* ! APR_POLL_H */
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