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
210
211
212
213
214
215
216
217
218
219
|
/* $OpenLDAP$ */
/* This work is part of OpenLDAP Software <http://www.openldap.org/>.
*
* Copyright 2006-2018 The OpenLDAP Foundation.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted only as authorized by the OpenLDAP
* Public License.
*
* A copy of this license is available in file LICENSE in the
* top-level directory of the distribution or, alternatively, at
* <http://www.OpenLDAP.org/license.html>.
*/
/* This work was initially developed by Howard Chu for inclusion
* in OpenLDAP Software.
*/
/*
* This is an implementation of recursive mutexes.
*/
#include "portable.h"
#include <ac/stdlib.h>
#include <ac/errno.h>
#include <ac/string.h>
#include <ac/time.h>
#include "ldap-int.h"
#include "ldap_pvt_thread.h" /* Get the thread interface */
struct ldap_int_thread_rmutex_s {
ldap_pvt_thread_mutex_t ltrm_mutex;
ldap_pvt_thread_cond_t ltrm_cond;
ldap_pvt_thread_t ltrm_owner;
int ltrm_valid;
#define LDAP_PVT_THREAD_RMUTEX_VALID 0x0cdb
int ltrm_depth;
int ltrm_waits;
};
static const ldap_pvt_thread_t tid_zero;
int
ldap_pvt_thread_rmutex_init( ldap_pvt_thread_rmutex_t *rmutex )
{
struct ldap_int_thread_rmutex_s *rm;
assert( rmutex != NULL );
rm = (struct ldap_int_thread_rmutex_s *) LDAP_CALLOC( 1,
sizeof( struct ldap_int_thread_rmutex_s ) );
if ( !rm )
return LDAP_NO_MEMORY;
/* we should check return results */
ldap_pvt_thread_mutex_init( &rm->ltrm_mutex );
ldap_pvt_thread_cond_init( &rm->ltrm_cond );
rm->ltrm_valid = LDAP_PVT_THREAD_RMUTEX_VALID;
*rmutex = rm;
return 0;
}
int
ldap_pvt_thread_rmutex_destroy( ldap_pvt_thread_rmutex_t *rmutex )
{
struct ldap_int_thread_rmutex_s *rm;
assert( rmutex != NULL );
rm = *rmutex;
assert( rm != NULL );
assert( rm->ltrm_valid == LDAP_PVT_THREAD_RMUTEX_VALID );
if( rm->ltrm_valid != LDAP_PVT_THREAD_RMUTEX_VALID )
return LDAP_PVT_THREAD_EINVAL;
ldap_pvt_thread_mutex_lock( &rm->ltrm_mutex );
assert( rm->ltrm_depth >= 0 );
assert( rm->ltrm_waits >= 0 );
/* in use? */
if( rm->ltrm_depth > 0 || rm->ltrm_waits > 0 ) {
ldap_pvt_thread_mutex_unlock( &rm->ltrm_mutex );
return LDAP_PVT_THREAD_EBUSY;
}
rm->ltrm_valid = 0;
ldap_pvt_thread_mutex_unlock( &rm->ltrm_mutex );
ldap_pvt_thread_mutex_destroy( &rm->ltrm_mutex );
ldap_pvt_thread_cond_destroy( &rm->ltrm_cond );
LDAP_FREE(rm);
*rmutex = NULL;
return 0;
}
int ldap_pvt_thread_rmutex_lock( ldap_pvt_thread_rmutex_t *rmutex,
ldap_pvt_thread_t owner )
{
struct ldap_int_thread_rmutex_s *rm;
assert( rmutex != NULL );
rm = *rmutex;
assert( rm != NULL );
assert( rm->ltrm_valid == LDAP_PVT_THREAD_RMUTEX_VALID );
if( rm->ltrm_valid != LDAP_PVT_THREAD_RMUTEX_VALID )
return LDAP_PVT_THREAD_EINVAL;
ldap_pvt_thread_mutex_lock( &rm->ltrm_mutex );
assert( rm->ltrm_depth >= 0 );
assert( rm->ltrm_waits >= 0 );
if( rm->ltrm_depth > 0 ) {
/* already locked */
if ( !ldap_pvt_thread_equal( rm->ltrm_owner, owner )) {
rm->ltrm_waits++;
do {
ldap_pvt_thread_cond_wait( &rm->ltrm_cond,
&rm->ltrm_mutex );
} while( rm->ltrm_depth > 0 );
rm->ltrm_waits--;
assert( rm->ltrm_waits >= 0 );
rm->ltrm_owner = owner;
}
} else {
rm->ltrm_owner = owner;
}
rm->ltrm_depth++;
ldap_pvt_thread_mutex_unlock( &rm->ltrm_mutex );
return 0;
}
int ldap_pvt_thread_rmutex_trylock( ldap_pvt_thread_rmutex_t *rmutex,
ldap_pvt_thread_t owner )
{
struct ldap_int_thread_rmutex_s *rm;
assert( rmutex != NULL );
rm = *rmutex;
assert( rm != NULL );
assert( rm->ltrm_valid == LDAP_PVT_THREAD_RMUTEX_VALID );
if( rm->ltrm_valid != LDAP_PVT_THREAD_RMUTEX_VALID )
return LDAP_PVT_THREAD_EINVAL;
ldap_pvt_thread_mutex_lock( &rm->ltrm_mutex );
assert( rm->ltrm_depth >= 0 );
assert( rm->ltrm_waits >= 0 );
if( rm->ltrm_depth > 0 ) {
if ( !ldap_pvt_thread_equal( owner, rm->ltrm_owner )) {
ldap_pvt_thread_mutex_unlock( &rm->ltrm_mutex );
return LDAP_PVT_THREAD_EBUSY;
}
} else {
rm->ltrm_owner = owner;
}
rm->ltrm_depth++;
ldap_pvt_thread_mutex_unlock( &rm->ltrm_mutex );
return 0;
}
int ldap_pvt_thread_rmutex_unlock( ldap_pvt_thread_rmutex_t *rmutex,
ldap_pvt_thread_t owner )
{
struct ldap_int_thread_rmutex_s *rm;
assert( rmutex != NULL );
rm = *rmutex;
assert( rm != NULL );
assert( rm->ltrm_valid == LDAP_PVT_THREAD_RMUTEX_VALID );
if( rm->ltrm_valid != LDAP_PVT_THREAD_RMUTEX_VALID )
return LDAP_PVT_THREAD_EINVAL;
ldap_pvt_thread_mutex_lock( &rm->ltrm_mutex );
if( !ldap_pvt_thread_equal( owner, rm->ltrm_owner )) {
ldap_pvt_thread_mutex_unlock( &rm->ltrm_mutex );
return LDAP_PVT_THREAD_EINVAL;
}
rm->ltrm_depth--;
if ( !rm->ltrm_depth )
rm->ltrm_owner = tid_zero;
assert( rm->ltrm_depth >= 0 );
assert( rm->ltrm_waits >= 0 );
if ( !rm->ltrm_depth && rm->ltrm_waits ) {
ldap_pvt_thread_cond_signal( &rm->ltrm_cond );
}
ldap_pvt_thread_mutex_unlock( &rm->ltrm_mutex );
return 0;
}
|
