00001 /* Licensed to the Apache Software Foundation (ASF) under one or more 00002 * contributor license agreements. See the NOTICE file distributed with 00003 * this work for additional information regarding copyright ownership. 00004 * The ASF licenses this file to You under the Apache License, Version 2.0 00005 * (the "License"); you may not use this file except in compliance with 00006 * the License. You may obtain a copy of the License at 00007 * 00008 * http://www.apache.org/licenses/LICENSE-2.0 00009 * 00010 * Unless required by applicable law or agreed to in writing, software 00011 * distributed under the License is distributed on an "AS IS" BASIS, 00012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 00013 * See the License for the specific language governing permissions and 00014 * limitations under the License. 00015 */ 00016 00017 #ifndef APR_POLL_H 00018 #define APR_POLL_H 00019 /** 00020 * @file apr_poll.h 00021 * @brief APR Poll interface 00022 */ 00023 #include "apr.h" 00024 #include "apr_pools.h" 00025 #include "apr_errno.h" 00026 #include "apr_inherit.h" 00027 #include "apr_file_io.h" 00028 #include "apr_network_io.h" 00029 00030 #if APR_HAVE_NETINET_IN_H 00031 #include <netinet/in.h> 00032 #endif 00033 00034 #ifdef __cplusplus 00035 extern "C" { 00036 #endif /* __cplusplus */ 00037 00038 /** 00039 * @defgroup apr_poll Poll Routines 00040 * @ingroup APR 00041 * @{ 00042 */ 00043 00044 /** 00045 * Poll options 00046 */ 00047 #define APR_POLLIN 0x001 /**< Can read without blocking */ 00048 #define APR_POLLPRI 0x002 /**< Priority data available */ 00049 #define APR_POLLOUT 0x004 /**< Can write without blocking */ 00050 #define APR_POLLERR 0x010 /**< Pending error */ 00051 #define APR_POLLHUP 0x020 /**< Hangup occurred */ 00052 #define APR_POLLNVAL 0x040 /**< Descriptor invalid */ 00053 00054 /** 00055 * Pollset Flags 00056 */ 00057 #define APR_POLLSET_THREADSAFE 0x001 /**< Adding or removing a descriptor is 00058 * thread-safe 00059 */ 00060 #define APR_POLLSET_NOCOPY 0x002 /**< Descriptors passed to apr_pollset_add() 00061 * are not copied 00062 */ 00063 #define APR_POLLSET_WAKEABLE 0x004 /**< Poll operations are interruptable by 00064 * apr_pollset_wakeup() 00065 */ 00066 #define APR_POLLSET_NODEFAULT 0x010 /**< Do not try to use the default method if 00067 * the specified non-default method cannot be 00068 * used 00069 */ 00070 00071 /** 00072 * Pollset Methods 00073 */ 00074 typedef enum { 00075 APR_POLLSET_DEFAULT, /**< Platform default poll method */ 00076 APR_POLLSET_SELECT, /**< Poll uses select method */ 00077 APR_POLLSET_KQUEUE, /**< Poll uses kqueue method */ 00078 APR_POLLSET_PORT, /**< Poll uses Solaris event port method */ 00079 APR_POLLSET_EPOLL, /**< Poll uses epoll method */ 00080 APR_POLLSET_POLL, /**< Poll uses poll method */ 00081 APR_POLLSET_AIO_MSGQ /**< Poll uses z/OS asio method */ 00082 } apr_pollset_method_e; 00083 00084 /** Used in apr_pollfd_t to determine what the apr_descriptor is */ 00085 typedef enum { 00086 APR_NO_DESC, /**< nothing here */ 00087 APR_POLL_SOCKET, /**< descriptor refers to a socket */ 00088 APR_POLL_FILE, /**< descriptor refers to a file */ 00089 APR_POLL_LASTDESC /**< @deprecated descriptor is the last one in the list */ 00090 } apr_datatype_e ; 00091 00092 /** Union of either an APR file or socket. */ 00093 typedef union { 00094 apr_file_t *f; /**< file */ 00095 apr_socket_t *s; /**< socket */ 00096 } apr_descriptor; 00097 00098 /** @see apr_pollfd_t */ 00099 typedef struct apr_pollfd_t apr_pollfd_t; 00100 00101 /** Poll descriptor set. */ 00102 struct apr_pollfd_t { 00103 apr_pool_t *p; /**< associated pool */ 00104 apr_datatype_e desc_type; /**< descriptor type */ 00105 apr_int16_t reqevents; /**< requested events */ 00106 apr_int16_t rtnevents; /**< returned events */ 00107 apr_descriptor desc; /**< @see apr_descriptor */ 00108 void *client_data; /**< allows app to associate context */ 00109 }; 00110 00111 00112 /* General-purpose poll API for arbitrarily large numbers of 00113 * file descriptors 00114 */ 00115 00116 /** Opaque structure used for pollset API */ 00117 typedef struct apr_pollset_t apr_pollset_t; 00118 00119 /** 00120 * Set up a pollset object 00121 * @param pollset The pointer in which to return the newly created object 00122 * @param size The maximum number of descriptors that this pollset can hold 00123 * @param p The pool from which to allocate the pollset 00124 * @param flags Optional flags to modify the operation of the pollset. 00125 * 00126 * @remark If flags contains APR_POLLSET_THREADSAFE, then a pollset is 00127 * created on which it is safe to make concurrent calls to 00128 * apr_pollset_add(), apr_pollset_remove() and apr_pollset_poll() 00129 * from separate threads. This feature is only supported on some 00130 * platforms; the apr_pollset_create() call will fail with 00131 * APR_ENOTIMPL on platforms where it is not supported. 00132 * @remark If flags contains APR_POLLSET_WAKEABLE, then a pollset is 00133 * created with an additional internal pipe object used for the 00134 * apr_pollset_wakeup() call. The actual size of pollset is 00135 * in that case @a size + 1. This feature is only supported on some 00136 * platforms; the apr_pollset_create() call will fail with 00137 * APR_ENOTIMPL on platforms where it is not supported. 00138 * @remark If flags contains APR_POLLSET_NOCOPY, then the apr_pollfd_t 00139 * structures passed to apr_pollset_add() are not copied and 00140 * must have a lifetime at least as long as the pollset. 00141 * @remark Some poll methods (including APR_POLLSET_KQUEUE, 00142 * APR_POLLSET_PORT, and APR_POLLSET_EPOLL) do not have a 00143 * fixed limit on the size of the pollset. For these methods, 00144 * the size parameter controls the maximum number of 00145 * descriptors that will be returned by a single call to 00146 * apr_pollset_poll(). 00147 */ 00148 APR_DECLARE(apr_status_t) apr_pollset_create(apr_pollset_t **pollset, 00149 apr_uint32_t size, 00150 apr_pool_t *p, 00151 apr_uint32_t flags); 00152 00153 /** 00154 * Set up a pollset object 00155 * @param pollset The pointer in which to return the newly created object 00156 * @param size The maximum number of descriptors that this pollset can hold 00157 * @param p The pool from which to allocate the pollset 00158 * @param flags Optional flags to modify the operation of the pollset. 00159 * @param method Poll method to use. See #apr_pollset_method_e. If this 00160 * method cannot be used, the default method will be used unless the 00161 * APR_POLLSET_NODEFAULT flag has been specified. 00162 * 00163 * @remark If flags contains APR_POLLSET_THREADSAFE, then a pollset is 00164 * created on which it is safe to make concurrent calls to 00165 * apr_pollset_add(), apr_pollset_remove() and apr_pollset_poll() 00166 * from separate threads. This feature is only supported on some 00167 * platforms; the apr_pollset_create_ex() call will fail with 00168 * APR_ENOTIMPL on platforms where it is not supported. 00169 * @remark If flags contains APR_POLLSET_WAKEABLE, then a pollset is 00170 * created with additional internal pipe object used for the 00171 * apr_pollset_wakeup() call. The actual size of pollset is 00172 * in that case size + 1. This feature is only supported on some 00173 * platforms; the apr_pollset_create_ex() call will fail with 00174 * APR_ENOTIMPL on platforms where it is not supported. 00175 * @remark If flags contains APR_POLLSET_NOCOPY, then the apr_pollfd_t 00176 * structures passed to apr_pollset_add() are not copied and 00177 * must have a lifetime at least as long as the pollset. 00178 * @remark Some poll methods (including APR_POLLSET_KQUEUE, 00179 * APR_POLLSET_PORT, and APR_POLLSET_EPOLL) do not have a 00180 * fixed limit on the size of the pollset. For these methods, 00181 * the size parameter controls the maximum number of 00182 * descriptors that will be returned by a single call to 00183 * apr_pollset_poll(). 00184 */ 00185 APR_DECLARE(apr_status_t) apr_pollset_create_ex(apr_pollset_t **pollset, 00186 apr_uint32_t size, 00187 apr_pool_t *p, 00188 apr_uint32_t flags, 00189 apr_pollset_method_e method); 00190 00191 /** 00192 * Destroy a pollset object 00193 * @param pollset The pollset to destroy 00194 */ 00195 APR_DECLARE(apr_status_t) apr_pollset_destroy(apr_pollset_t *pollset); 00196 00197 /** 00198 * Add a socket or file descriptor to a pollset 00199 * @param pollset The pollset to which to add the descriptor 00200 * @param descriptor The descriptor to add 00201 * @remark If you set client_data in the descriptor, that value 00202 * will be returned in the client_data field whenever this 00203 * descriptor is signalled in apr_pollset_poll(). 00204 * @remark If the pollset has been created with APR_POLLSET_THREADSAFE 00205 * and thread T1 is blocked in a call to apr_pollset_poll() for 00206 * this same pollset that is being modified via apr_pollset_add() 00207 * in thread T2, the currently executing apr_pollset_poll() call in 00208 * T1 will either: (1) automatically include the newly added descriptor 00209 * in the set of descriptors it is watching or (2) return immediately 00210 * with APR_EINTR. Option (1) is recommended, but option (2) is 00211 * allowed for implementations where option (1) is impossible 00212 * or impractical. 00213 * @remark If the pollset has been created with APR_POLLSET_NOCOPY, the 00214 * apr_pollfd_t structure referenced by descriptor will not be copied 00215 * and must have a lifetime at least as long as the pollset. 00216 * @remark Do not add the same socket or file descriptor to the same pollset 00217 * multiple times, even if the requested events differ for the 00218 * different calls to apr_pollset_add(). If the events of interest 00219 * for a descriptor change, you must first remove the descriptor 00220 * from the pollset with apr_pollset_remove(), then add it again 00221 * specifying all requested events. 00222 */ 00223 APR_DECLARE(apr_status_t) apr_pollset_add(apr_pollset_t *pollset, 00224 const apr_pollfd_t *descriptor); 00225 00226 /** 00227 * Remove a descriptor from a pollset 00228 * @param pollset The pollset from which to remove the descriptor 00229 * @param descriptor The descriptor to remove 00230 * @remark If the descriptor is not found, APR_NOTFOUND is returned. 00231 * @remark If the pollset has been created with APR_POLLSET_THREADSAFE 00232 * and thread T1 is blocked in a call to apr_pollset_poll() for 00233 * this same pollset that is being modified via apr_pollset_remove() 00234 * in thread T2, the currently executing apr_pollset_poll() call in 00235 * T1 will either: (1) automatically exclude the newly added descriptor 00236 * in the set of descriptors it is watching or (2) return immediately 00237 * with APR_EINTR. Option (1) is recommended, but option (2) is 00238 * allowed for implementations where option (1) is impossible 00239 * or impractical. 00240 * @remark apr_pollset_remove() cannot be used to remove a subset of requested 00241 * events for a descriptor. The reqevents field in the apr_pollfd_t 00242 * parameter must contain the same value when removing as when adding. 00243 */ 00244 APR_DECLARE(apr_status_t) apr_pollset_remove(apr_pollset_t *pollset, 00245 const apr_pollfd_t *descriptor); 00246 00247 /** 00248 * Block for activity on the descriptor(s) in a pollset 00249 * @param pollset The pollset to use 00250 * @param timeout The amount of time in microseconds to wait. This is a 00251 * maximum, not a minimum. If a descriptor is signalled, the 00252 * function will return before this time. If timeout is 00253 * negative, the function will block until a descriptor is 00254 * signalled or until apr_pollset_wakeup() has been called. 00255 * @param num Number of signalled descriptors (output parameter) 00256 * @param descriptors Array of signalled descriptors (output parameter) 00257 * @remark APR_EINTR will be returned if the pollset has been created with 00258 * APR_POLLSET_WAKEABLE, apr_pollset_wakeup() has been called while 00259 * waiting for activity, and there were no signalled descriptors at the 00260 * time of the wakeup call. 00261 * @remark Multiple signalled conditions for the same descriptor may be reported 00262 * in one or more returned apr_pollfd_t structures, depending on the 00263 * implementation. 00264 */ 00265 APR_DECLARE(apr_status_t) apr_pollset_poll(apr_pollset_t *pollset, 00266 apr_interval_time_t timeout, 00267 apr_int32_t *num, 00268 const apr_pollfd_t **descriptors); 00269 00270 /** 00271 * Interrupt the blocked apr_pollset_poll() call. 00272 * @param pollset The pollset to use 00273 * @remark If the pollset was not created with APR_POLLSET_WAKEABLE the 00274 * return value is APR_EINIT. 00275 */ 00276 APR_DECLARE(apr_status_t) apr_pollset_wakeup(apr_pollset_t *pollset); 00277 00278 /** 00279 * Poll the descriptors in the poll structure 00280 * @param aprset The poll structure we will be using. 00281 * @param numsock The number of descriptors we are polling 00282 * @param nsds The number of descriptors signalled (output parameter) 00283 * @param timeout The amount of time in microseconds to wait. This is a 00284 * maximum, not a minimum. If a descriptor is signalled, the 00285 * function will return before this time. If timeout is 00286 * negative, the function will block until a descriptor is 00287 * signalled or until apr_pollset_wakeup() has been called. 00288 * @remark The number of descriptors signalled is returned in the third argument. 00289 * This is a blocking call, and it will not return until either a 00290 * descriptor has been signalled or the timeout has expired. 00291 * @remark The rtnevents field in the apr_pollfd_t array will only be filled- 00292 * in if the return value is APR_SUCCESS. 00293 */ 00294 APR_DECLARE(apr_status_t) apr_poll(apr_pollfd_t *aprset, apr_int32_t numsock, 00295 apr_int32_t *nsds, 00296 apr_interval_time_t timeout); 00297 00298 /** 00299 * Return a printable representation of the pollset method. 00300 * @param pollset The pollset to use 00301 */ 00302 APR_DECLARE(const char *) apr_pollset_method_name(apr_pollset_t *pollset); 00303 00304 /** 00305 * Return a printable representation of the default pollset method 00306 * (APR_POLLSET_DEFAULT). 00307 */ 00308 APR_DECLARE(const char *) apr_poll_method_defname(void); 00309 00310 /** Opaque structure used for pollcb API */ 00311 typedef struct apr_pollcb_t apr_pollcb_t; 00312 00313 /** 00314 * Set up a pollcb object 00315 * @param pollcb The pointer in which to return the newly created object 00316 * @param size The maximum number of descriptors that a single _poll can return. 00317 * @param p The pool from which to allocate the pollcb 00318 * @param flags Optional flags to modify the operation of the pollcb. 00319 * 00320 * @remark Pollcb is only supported on some platforms; the apr_pollcb_create() 00321 * call will fail with APR_ENOTIMPL on platforms where it is not supported. 00322 */ 00323 APR_DECLARE(apr_status_t) apr_pollcb_create(apr_pollcb_t **pollcb, 00324 apr_uint32_t size, 00325 apr_pool_t *p, 00326 apr_uint32_t flags); 00327 00328 /** 00329 * Set up a pollcb object 00330 * @param pollcb The pointer in which to return the newly created object 00331 * @param size The maximum number of descriptors that a single _poll can return. 00332 * @param p The pool from which to allocate the pollcb 00333 * @param flags Optional flags to modify the operation of the pollcb. 00334 * @param method Poll method to use. See #apr_pollset_method_e. If this 00335 * method cannot be used, the default method will be used unless the 00336 * APR_POLLSET_NODEFAULT flag has been specified. 00337 * 00338 * @remark Pollcb is only supported on some platforms; the apr_pollcb_create_ex() 00339 * call will fail with APR_ENOTIMPL on platforms where it is not supported. 00340 */ 00341 APR_DECLARE(apr_status_t) apr_pollcb_create_ex(apr_pollcb_t **pollcb, 00342 apr_uint32_t size, 00343 apr_pool_t *p, 00344 apr_uint32_t flags, 00345 apr_pollset_method_e method); 00346 00347 /** 00348 * Add a socket or file descriptor to a pollcb 00349 * @param pollcb The pollcb to which to add the descriptor 00350 * @param descriptor The descriptor to add 00351 * @remark If you set client_data in the descriptor, that value will be 00352 * returned in the client_data field whenever this descriptor is 00353 * signalled in apr_pollcb_poll(). 00354 * @remark Unlike the apr_pollset API, the descriptor is not copied, and users 00355 * must retain the memory used by descriptor, as the same pointer will 00356 * be returned to them from apr_pollcb_poll. 00357 * @remark Do not add the same socket or file descriptor to the same pollcb 00358 * multiple times, even if the requested events differ for the 00359 * different calls to apr_pollcb_add(). If the events of interest 00360 * for a descriptor change, you must first remove the descriptor 00361 * from the pollcb with apr_pollcb_remove(), then add it again 00362 * specifying all requested events. 00363 */ 00364 APR_DECLARE(apr_status_t) apr_pollcb_add(apr_pollcb_t *pollcb, 00365 apr_pollfd_t *descriptor); 00366 /** 00367 * Remove a descriptor from a pollcb 00368 * @param pollcb The pollcb from which to remove the descriptor 00369 * @param descriptor The descriptor to remove 00370 * @remark apr_pollcb_remove() cannot be used to remove a subset of requested 00371 * events for a descriptor. The reqevents field in the apr_pollfd_t 00372 * parameter must contain the same value when removing as when adding. 00373 */ 00374 APR_DECLARE(apr_status_t) apr_pollcb_remove(apr_pollcb_t *pollcb, 00375 apr_pollfd_t *descriptor); 00376 00377 /** Function prototype for pollcb handlers 00378 * @param baton Opaque baton passed into apr_pollcb_poll() 00379 * @param descriptor Contains the notification for an active descriptor, 00380 * the rtnevents member contains what events were triggered 00381 * for this descriptor. 00382 */ 00383 typedef apr_status_t (*apr_pollcb_cb_t)(void *baton, apr_pollfd_t *descriptor); 00384 00385 /** 00386 * Block for activity on the descriptor(s) in a pollcb 00387 * @param pollcb The pollcb to use 00388 * @param timeout The amount of time in microseconds to wait. This is a 00389 * maximum, not a minimum. If a descriptor is signalled, the 00390 * function will return before this time. If timeout is 00391 * negative, the function will block until a descriptor is 00392 * signalled. 00393 * @param func Callback function to call for each active descriptor. 00394 * @param baton Opaque baton passed to the callback function. 00395 * @remark Multiple signalled conditions for the same descriptor may be reported 00396 * in one or more calls to the callback function, depending on the 00397 * implementation. 00398 */ 00399 APR_DECLARE(apr_status_t) apr_pollcb_poll(apr_pollcb_t *pollcb, 00400 apr_interval_time_t timeout, 00401 apr_pollcb_cb_t func, 00402 void *baton); 00403 00404 /** @} */ 00405 00406 #ifdef __cplusplus 00407 } 00408 #endif 00409 00410 #endif /* ! APR_POLL_H */ 00411