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 #include "apr_shm.h"
18 #include "apr_thread_proc.h"
19 #include "apr_file_io.h"
20 #include "apr_proc_mutex.h"
21 #include "apr_errno.h"
22 #include "apr_general.h"
23 #include "apr_getopt.h"
24 #include <stdio.h>
25 #include <stdlib.h>
26 #include "testutil.h"
27
28 #if APR_HAS_FORK
29
30 #define MAX_ITER 200
31 #define CHILDREN 6
32 #define MAX_COUNTER (MAX_ITER * CHILDREN)
33 #define MAX_WAIT_USEC (1000*1000)
34
35 static apr_proc_mutex_t *proc_lock;
36 static volatile int *x;
37
38 /* a slower more racy way to implement (*x)++ */
increment(int n)39 static int increment(int n)
40 {
41 apr_sleep(1);
42 return n+1;
43 }
44
make_child(abts_case * tc,int trylock,apr_proc_t ** proc,apr_pool_t * p)45 static void make_child(abts_case *tc, int trylock, apr_proc_t **proc, apr_pool_t *p)
46 {
47 apr_status_t rv;
48
49 *proc = apr_pcalloc(p, sizeof(**proc));
50
51 /* slight delay to allow things to settle */
52 apr_sleep (1);
53
54 rv = apr_proc_fork(*proc, p);
55 if (rv == APR_INCHILD) {
56 int i = 0;
57 /* The parent process has setup all processes to call apr_terminate
58 * at exit. But, that means that all processes must also call
59 * apr_initialize at startup. You cannot have an unequal number
60 * of apr_terminate and apr_initialize calls. If you do, bad things
61 * will happen. In this case, the bad thing is that if the mutex
62 * is a semaphore, it will be destroyed before all of the processes
63 * die. That means that the test will most likely fail.
64 */
65 apr_initialize();
66
67 if (apr_proc_mutex_child_init(&proc_lock, NULL, p))
68 exit(1);
69
70 do {
71 if (trylock) {
72 int wait_usec = 0;
73
74 while ((rv = apr_proc_mutex_trylock(proc_lock))) {
75 if (!APR_STATUS_IS_EBUSY(rv))
76 exit(1);
77 if (++wait_usec >= MAX_WAIT_USEC)
78 exit(1);
79 apr_sleep(1);
80 }
81 }
82 else {
83 if (apr_proc_mutex_lock(proc_lock))
84 exit(1);
85 }
86
87 i++;
88 *x = increment(*x);
89 if (apr_proc_mutex_unlock(proc_lock))
90 exit(1);
91 } while (i < MAX_ITER);
92 exit(0);
93 }
94
95 ABTS_ASSERT(tc, "fork failed", rv == APR_INPARENT);
96 }
97
98 /* Wait for a child process and check it terminated with success. */
await_child(abts_case * tc,apr_proc_t * proc)99 static void await_child(abts_case *tc, apr_proc_t *proc)
100 {
101 int code;
102 apr_exit_why_e why;
103 apr_status_t rv;
104
105 rv = apr_proc_wait(proc, &code, &why, APR_WAIT);
106 ABTS_ASSERT(tc, "child did not terminate with success",
107 rv == APR_CHILD_DONE && why == APR_PROC_EXIT && code == 0);
108 }
109
test_exclusive(abts_case * tc,const char * lockname,apr_lockmech_e mech)110 static void test_exclusive(abts_case *tc, const char *lockname,
111 apr_lockmech_e mech)
112 {
113 apr_proc_t *child[CHILDREN];
114 apr_status_t rv;
115 int n;
116
117 rv = apr_proc_mutex_create(&proc_lock, lockname, mech, p);
118 APR_ASSERT_SUCCESS(tc, "create the mutex", rv);
119 if (rv != APR_SUCCESS)
120 return;
121
122 for (n = 0; n < CHILDREN; n++)
123 make_child(tc, 0, &child[n], p);
124
125 for (n = 0; n < CHILDREN; n++)
126 await_child(tc, child[n]);
127
128 ABTS_ASSERT(tc, "Locks don't appear to work", *x == MAX_COUNTER);
129
130 rv = apr_proc_mutex_trylock(proc_lock);
131 if (rv == APR_ENOTIMPL) {
132 ABTS_NOT_IMPL(tc, "apr_proc_mutex_trylock not implemented");
133 return;
134 }
135 APR_ASSERT_SUCCESS(tc, "check for trylock", rv);
136
137 rv = apr_proc_mutex_unlock(proc_lock);
138 APR_ASSERT_SUCCESS(tc, "unlock after trylock check", rv);
139
140 *x = 0;
141
142 for (n = 0; n < CHILDREN; n++)
143 make_child(tc, 1, &child[n], p);
144
145 for (n = 0; n < CHILDREN; n++)
146 await_child(tc, child[n]);
147
148 ABTS_ASSERT(tc, "Locks don't appear to work with trylock",
149 *x == MAX_COUNTER);
150 }
151 #endif
152
proc_mutex(abts_case * tc,void * data)153 static void proc_mutex(abts_case *tc, void *data)
154 {
155 #if APR_HAS_FORK
156 apr_status_t rv;
157 const char *shmname = "tpm.shm";
158 apr_shm_t *shm;
159 apr_lockmech_e *mech = data;
160
161 /* Use anonymous shm if available. */
162 rv = apr_shm_create(&shm, sizeof(int), NULL, p);
163 if (rv == APR_ENOTIMPL) {
164 apr_file_remove(shmname, p);
165 rv = apr_shm_create(&shm, sizeof(int), shmname, p);
166 }
167
168 APR_ASSERT_SUCCESS(tc, "create shm segment", rv);
169 if (rv != APR_SUCCESS)
170 return;
171
172 x = apr_shm_baseaddr_get(shm);
173 test_exclusive(tc, NULL, *mech);
174 rv = apr_shm_destroy(shm);
175 APR_ASSERT_SUCCESS(tc, "Error destroying shared memory block", rv);
176 #else
177 ABTS_NOT_IMPL(tc, "APR lacks fork() support");
178 #endif
179 }
180
181
testprocmutex(abts_suite * suite)182 abts_suite *testprocmutex(abts_suite *suite)
183 {
184 apr_lockmech_e mech = APR_LOCK_DEFAULT;
185
186 suite = ADD_SUITE(suite)
187 abts_run_test(suite, proc_mutex, &mech);
188 #if APR_HAS_POSIXSEM_SERIALIZE
189 mech = APR_LOCK_POSIXSEM;
190 abts_run_test(suite, proc_mutex, &mech);
191 #endif
192 #if APR_HAS_SYSVSEM_SERIALIZE
193 mech = APR_LOCK_SYSVSEM;
194 abts_run_test(suite, proc_mutex, &mech);
195 #endif
196 #if APR_HAS_PROC_PTHREAD_SERIALIZE
197 mech = APR_LOCK_PROC_PTHREAD;
198 abts_run_test(suite, proc_mutex, &mech);
199 #endif
200 #if APR_HAS_FCNTL_SERIALIZE
201 mech = APR_LOCK_FCNTL;
202 abts_run_test(suite, proc_mutex, &mech);
203 #endif
204 #if APR_HAS_FLOCK_SERIALIZE
205 mech = APR_LOCK_FLOCK;
206 abts_run_test(suite, proc_mutex, &mech);
207 #endif
208
209 return suite;
210 }
211