/*
* Bacula Thread Read/Write locking code. It permits
- * multiple readers but only one writer.
+ * multiple readers but only one writer.
*
* Kern Sibbald, January MMI
*
*
*/
/*
- Copyright (C) 2000, 2001, 2002 Kern Sibbald and John Walker
+ Copyright (C) 2000-2003 Kern Sibbald and John Walker
This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License as
*/
-#ifndef __RWLOCK_H
+#ifndef __RWLOCK_H
#define __RWLOCK_H 1
-typedef struct rwlock_tag {
+typedef struct s_rwlock_tag {
pthread_mutex_t mutex;
- pthread_cond_t read; /* wait for read */
- pthread_cond_t write; /* wait for write */
- int valid; /* set when valid */
- int r_active; /* readers active */
- int w_active; /* writers active */
- int r_wait; /* readers waiting */
- int w_wait; /* writers waiting */
-} rwlock_t;
+ pthread_cond_t read; /* wait for read */
+ pthread_cond_t write; /* wait for write */
+ pthread_t writer_id; /* writer's thread id */
+ int valid; /* set when valid */
+ int r_active; /* readers active */
+ int w_active; /* writers active */
+ int r_wait; /* readers waiting */
+ int w_wait; /* writers waiting */
+} brwlock_t;
+
+typedef struct s_rwsteal_tag {
+ pthread_t writer_id; /* writer's thread id */
+ int state;
+} brwsteal_t;
+
#define RWLOCK_VALID 0xfacade
{PTHREAD_MUTEX_INITIALIZER, PTHREAD_COND_INITIALIZER, \
PTHREAD_COND_INITIALIZER, RWLOCK_VALID, 0, 0, 0, 0}
-/*
+/*
* read/write lock prototypes
*/
-extern int rwl_init(rwlock_t *wrlock);
-extern int rwl_destroy(rwlock_t *rwlock);
-extern int rwl_readlock(rwlock_t *rwlock);
-extern int rwl_readtrylock(rwlock_t *rwlock);
-extern int rwl_readunlock(rwlock_t *rwlock);
-extern int rwl_writelock(rwlock_t *rwlock);
-extern int rwl_writetrylock(rwlock_t *rwlock);
-extern int rwl_writeunlock(rwlock_t *rwlock);
+extern int rwl_init(brwlock_t *wrlock);
+extern int rwl_destroy(brwlock_t *rwlock);
+extern int rwl_readlock(brwlock_t *rwlock);
+extern int rwl_readtrylock(brwlock_t *rwlock);
+extern int rwl_readunlock(brwlock_t *rwlock);
+extern int rwl_writelock(brwlock_t *rwlock);
+extern int rwl_writetrylock(brwlock_t *rwlock);
+extern int rwl_writeunlock(brwlock_t *rwlock);
#endif /* __RWLOCK_H */