pollcb.c revision 269847 
1/* Licensed to the Apache Software Foundation (ASF) under one or more
2 * contributor license agreements.  See the NOTICE file distributed with
3 * this work for additional information regarding copyright ownership.
4 * The ASF licenses this file to You under the Apache License, Version 2.0
5 * (the "License"); you may not use this file except in compliance with
6 * the License.  You may obtain a copy of the License at
7 *
8 *     http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifdef WIN32
18/* POSIX defines 1024 for the FD_SETSIZE */
19#define FD_SETSIZE 1024
20#endif
21
22#include "apr.h"
23#include "apr_poll.h"
24#include "apr_time.h"
25#include "apr_portable.h"
26#include "apr_arch_file_io.h"
27#include "apr_arch_networkio.h"
28#include "apr_arch_poll_private.h"
29
30static apr_pollset_method_e pollset_default_method = POLLSET_DEFAULT_METHOD;
31#if defined(HAVE_KQUEUE)
32extern apr_pollcb_provider_t *apr_pollcb_provider_kqueue;
33#endif
34#if defined(HAVE_PORT_CREATE)
35extern apr_pollcb_provider_t *apr_pollcb_provider_port;
36#endif
37#if defined(HAVE_EPOLL)
38extern apr_pollcb_provider_t *apr_pollcb_provider_epoll;
39#endif
40#if defined(HAVE_POLL)
41extern apr_pollcb_provider_t *apr_pollcb_provider_poll;
42#endif
43
44static apr_pollcb_provider_t *pollcb_provider(apr_pollset_method_e method)
45{
46    apr_pollcb_provider_t *provider = NULL;
47    switch (method) {
48        case APR_POLLSET_KQUEUE:
49#if defined(HAVE_KQUEUE)
50            provider = apr_pollcb_provider_kqueue;
51#endif
52        break;
53        case APR_POLLSET_PORT:
54#if defined(HAVE_PORT_CREATE)
55            provider = apr_pollcb_provider_port;
56#endif
57        break;
58        case APR_POLLSET_EPOLL:
59#if defined(HAVE_EPOLL)
60            provider = apr_pollcb_provider_epoll;
61#endif
62        break;
63        case APR_POLLSET_POLL:
64#if defined(HAVE_POLL)
65            provider = apr_pollcb_provider_poll;
66#endif
67        break;
68        case APR_POLLSET_SELECT:
69        case APR_POLLSET_AIO_MSGQ:
70        case APR_POLLSET_DEFAULT:
71        break;
72    }
73    return provider;
74}
75
76APR_DECLARE(apr_status_t) apr_pollcb_create_ex(apr_pollcb_t **ret_pollcb,
77                                               apr_uint32_t size,
78                                               apr_pool_t *p,
79                                               apr_uint32_t flags,
80                                               apr_pollset_method_e method)
81{
82    apr_status_t rv;
83    apr_pollcb_t *pollcb;
84    apr_pollcb_provider_t *provider = NULL;
85
86    *ret_pollcb = NULL;
87
88 #ifdef WIN32
89    /* This will work only if ws2_32.dll has WSAPoll funtion.
90     * We could check the presence of the function here,
91     * but someone might implement other pollcb method in
92     * the future.
93     */
94    if (method == APR_POLLSET_DEFAULT) {
95        method = APR_POLLSET_POLL;
96    }
97 #endif
98
99    if (method == APR_POLLSET_DEFAULT)
100        method = pollset_default_method;
101    while (provider == NULL) {
102        provider = pollcb_provider(method);
103        if (!provider) {
104            if ((flags & APR_POLLSET_NODEFAULT) == APR_POLLSET_NODEFAULT)
105                return APR_ENOTIMPL;
106            if (method == pollset_default_method)
107                return APR_ENOTIMPL;
108            method = pollset_default_method;
109        }
110    }
111
112    pollcb = apr_palloc(p, sizeof(*pollcb));
113    pollcb->nelts = 0;
114    pollcb->nalloc = size;
115    pollcb->pool = p;
116    pollcb->provider = provider;
117
118    rv = (*provider->create)(pollcb, size, p, flags);
119    if (rv == APR_ENOTIMPL) {
120        if (method == pollset_default_method) {
121            return rv;
122        }
123
124        if ((flags & APR_POLLSET_NODEFAULT) == APR_POLLSET_NODEFAULT) {
125            return rv;
126        }
127
128        /* Try with default provider */
129        provider = pollcb_provider(pollset_default_method);
130        if (!provider) {
131            return APR_ENOTIMPL;
132        }
133        rv = (*provider->create)(pollcb, size, p, flags);
134        if (rv != APR_SUCCESS) {
135            return rv;
136        }
137        pollcb->provider = provider;
138    }
139
140    *ret_pollcb = pollcb;
141    return APR_SUCCESS;
142}
143
144APR_DECLARE(apr_status_t) apr_pollcb_create(apr_pollcb_t **pollcb,
145                                            apr_uint32_t size,
146                                            apr_pool_t *p,
147                                            apr_uint32_t flags)
148{
149    apr_pollset_method_e method = APR_POLLSET_DEFAULT;
150    return apr_pollcb_create_ex(pollcb, size, p, flags, method);
151}
152
153APR_DECLARE(apr_status_t) apr_pollcb_add(apr_pollcb_t *pollcb,
154                                         apr_pollfd_t *descriptor)
155{
156    return (*pollcb->provider->add)(pollcb, descriptor);
157}
158
159APR_DECLARE(apr_status_t) apr_pollcb_remove(apr_pollcb_t *pollcb,
160                                            apr_pollfd_t *descriptor)
161{
162    return (*pollcb->provider->remove)(pollcb, descriptor);
163}
164
165
166APR_DECLARE(apr_status_t) apr_pollcb_poll(apr_pollcb_t *pollcb,
167                                          apr_interval_time_t timeout,
168                                          apr_pollcb_cb_t func,
169                                          void *baton)
170{
171    return (*pollcb->provider->poll)(pollcb, timeout, func, baton);
172}
173