File: apu_dso.c

package info (click to toggle)
apr-util 1.6.1-5
  • links: PTS, VCS
  • area: main
  • in suites: bullseye, sid
  • size: 4,716 kB
  • sloc: ansic: 31,678; sh: 3,347; makefile: 222; perl: 154; xml: 36
file content (209 lines) | stat: -rw-r--r-- 5,871 bytes parent folder | download | duplicates (4)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
/* 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.
 */

#include <ctype.h>
#include <stdio.h>

#include "apu_config.h"
#include "apu.h"

#include "apr_pools.h"
#include "apr_tables.h"
#include "apr_dso.h"
#include "apr_strings.h"
#include "apr_hash.h"
#include "apr_file_io.h"
#include "apr_env.h"
#include "apr_atomic.h"

#include "apu_internal.h"
#include "apu_version.h"

#if APU_DSO_BUILD

#if APR_HAS_THREADS
static apr_thread_mutex_t* mutex = NULL;
#endif
static apr_hash_t *dsos = NULL;
static apr_uint32_t initialised = 0, in_init = 1;

#if APR_HAS_THREADS
apr_status_t apu_dso_mutex_lock()
{
    return apr_thread_mutex_lock(mutex);
}
apr_status_t apu_dso_mutex_unlock()
{
    return apr_thread_mutex_unlock(mutex);
}
#else
apr_status_t apu_dso_mutex_lock() {
    return APR_SUCCESS;
}
apr_status_t apu_dso_mutex_unlock() {
    return APR_SUCCESS;
}
#endif

static apr_status_t apu_dso_term(void *ptr)
{
    /* set statics to NULL so init can work again */
    dsos = NULL;
#if APR_HAS_THREADS
    mutex = NULL;
#endif

    /* Everything else we need is handled by cleanups registered
     * when we created mutexes and loaded DSOs
     */
    return APR_SUCCESS;
}

apr_status_t apu_dso_init(apr_pool_t *pool)
{
    apr_status_t ret = APR_SUCCESS;
    apr_pool_t *parent;

    if (apr_atomic_inc32(&initialised)) {
        apr_atomic_set32(&initialised, 1); /* prevent wrap-around */

        while (apr_atomic_read32(&in_init)) /* wait until we get fully inited */
            ;

        return APR_SUCCESS;
    }

    /* Top level pool scope, need process-scope lifetime */
    for (parent = apr_pool_parent_get(pool);
         parent && parent != pool;
         parent = apr_pool_parent_get(pool))
        pool = parent;

    dsos = apr_hash_make(pool);

#if APR_HAS_THREADS
    ret = apr_thread_mutex_create(&mutex, APR_THREAD_MUTEX_DEFAULT, pool);
    /* This already registers a pool cleanup */
#endif

    apr_pool_cleanup_register(pool, NULL, apu_dso_term,
                              apr_pool_cleanup_null);

    apr_atomic_dec32(&in_init);

    return ret;
}

apr_status_t apu_dso_load(apr_dso_handle_t **dlhandleptr,
                          apr_dso_handle_sym_t *dsoptr,
                          const char *module,
                          const char *modsym,
                          apr_pool_t *pool)
{
    apr_dso_handle_t *dlhandle = NULL;
    char *pathlist;
    char path[APR_PATH_MAX + 1];
    apr_array_header_t *paths;
    apr_pool_t *global;
    apr_status_t rv = APR_EDSOOPEN;
    char *eos = NULL;
    int i;

    *dsoptr = apr_hash_get(dsos, module, APR_HASH_KEY_STRING);
    if (*dsoptr) {
        return APR_EINIT;
    }

    /* The driver DSO must have exactly the same lifetime as the
     * drivers hash table; ignore the passed-in pool */
    global = apr_hash_pool_get(dsos);

    /* Retrieve our path search list or prepare for a single search */
    if ((apr_env_get(&pathlist, APR_DSOPATH, pool) != APR_SUCCESS)
          || (apr_filepath_list_split(&paths, pathlist, pool) != APR_SUCCESS))
        paths = apr_array_make(pool, 1, sizeof(char*));

#if defined(APU_DSO_LIBDIR)
    /* Always search our prefix path, but on some platforms such as
     * win32 this may be left undefined
     */
    (*((char **)apr_array_push(paths))) = APU_DSO_LIBDIR;
#endif

    for (i = 0; i < paths->nelts; ++i)
    {
#if defined(WIN32)
        /* Use win32 dso search semantics and attempt to
         * load the relative lib on the first pass.
         */
        if (!eos) {
            eos = path;
            --i;
        }
        else
#endif
        {
            eos = apr_cpystrn(path, ((char**)paths->elts)[i], sizeof(path));
            if ((eos > path) && (eos - path < sizeof(path) - 1))
                *(eos++) = '/';
        }
        apr_cpystrn(eos, module, sizeof(path) - (eos - path));

        rv = apr_dso_load(&dlhandle, path, global);
        if (dlhandleptr) {
            *dlhandleptr = dlhandle;
        }
        if (rv == APR_SUCCESS) { /* APR_EDSOOPEN */
            break;
        }
#if defined(APU_DSO_LIBDIR)
        else if (i < paths->nelts - 1) {
#else
        else {   /* No APU_DSO_LIBDIR to skip */
#endif
             /* try with apr-util-APU_MAJOR_VERSION appended */
            eos = apr_cpystrn(eos,
                              "apr-util-" APU_STRINGIFY(APU_MAJOR_VERSION) "/",
                              sizeof(path) - (eos - path));

            apr_cpystrn(eos, module, sizeof(path) - (eos - path));

            rv = apr_dso_load(&dlhandle, path, global);
            if (dlhandleptr) {
                *dlhandleptr = dlhandle;
            }
            if (rv == APR_SUCCESS) { /* APR_EDSOOPEN */
                break;
            }
        }
    }

    if (rv != APR_SUCCESS) /* APR_ESYMNOTFOUND */
        return rv;

    rv = apr_dso_sym(dsoptr, dlhandle, modsym);
    if (rv != APR_SUCCESS) { /* APR_ESYMNOTFOUND */
        apr_dso_unload(dlhandle);
    }
    else {
        module = apr_pstrdup(global, module);
        apr_hash_set(dsos, module, APR_HASH_KEY_STRING, *dsoptr);
    }
    return rv;
}

#endif /* APU_DSO_BUILD */