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Diffstat (limited to 'nest/locks.h')
| -rw-r--r-- | nest/locks.h | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/nest/locks.h b/nest/locks.h new file mode 100644 index 0000000..e465bf5 --- /dev/null +++ b/nest/locks.h @@ -0,0 +1,52 @@ +/* + * BIRD Object Locks + * + * (c) 1999 Martin Mares <mj@ucw.cz> + * + * Can be freely distributed and used under the terms of the GNU GPL. + */ + +#ifndef _BIRD_LOCKS_H_ +#define _BIRD_LOCKS_H_ + +#include "lib/resource.h" +#include "lib/event.h" + +/* + * The object locks are used for controlling exclusive access + * to various physical resources like UDP ports on specific devices. + * When you want to access such resource, you ask for a object lock + * structure, fill in specification of the object and your function + * you want to have called when the object is available and invoke + * olock_acquire() afterwards. When the object becomes free, the lock + * manager calls your function. To free the object lock, just call rfree + * on its resource. + */ + +struct object_lock { + resource r; + ip_addr addr; /* Identification of a object: IP address */ + unsigned int type; /* ... object type (OBJLOCK_xxx) */ + struct iface *iface; /* ... interface */ + unsigned int port; /* ... port number */ + void (*hook)(struct object_lock *); /* Called when the lock succeeds */ + void *data; /* User data */ + /* ... internal to lock manager, don't touch ... */ + node n; /* Node in list of olocks */ + int state; /* OLOCK_STATE_xxx */ + list waiters; /* Locks waiting for the same resource */ +}; + +struct object_lock *olock_new(pool *); +void olock_acquire(struct object_lock *); +void olock_init(void); + +#define OBJLOCK_UDP 1 /* UDP port */ +#define OBJLOCK_TCP 2 /* TCP port */ + +#define OLOCK_STATE_FREE 0 +#define OLOCK_STATE_LOCKED 1 +#define OLOCK_STATE_WAITING 2 +#define OLOCK_STATE_EVENT 3 /* waiting for unlock processing */ + +#endif |