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-rw-r--r--db2/include/lock.h197
1 files changed, 0 insertions, 197 deletions
diff --git a/db2/include/lock.h b/db2/include/lock.h
deleted file mode 100644
index 13364ca..0000000
--- a/db2/include/lock.h
+++ /dev/null
@@ -1,197 +0,0 @@
-/*-
- * See the file LICENSE for redistribution information.
- *
- * Copyright (c) 1996, 1997, 1998
- * Sleepycat Software. All rights reserved.
- *
- * @(#)lock.h 10.17 (Sleepycat) 1/3/99
- */
-
-typedef struct __db_lockobj DB_LOCKOBJ;
-
-#define DB_DEFAULT_LOCK_FILE "__db_lock.share"
-
-#ifndef DB_LOCK_DEFAULT_N
-#define DB_LOCK_DEFAULT_N 5000 /* Default # of locks in region. */
-#endif
-
-/*
- * The locker id space is divided between the transaction manager and the lock
- * manager. Lockid's start at 0 and go to DB_LOCK_MAXID. Txn Id's start at
- * DB_LOCK_MAXID + 1 and go up to TXN_INVALID.
- */
-#define DB_LOCK_MAXID 0x7fffffff
-
-/* Check for region catastrophic shutdown. */
-#define LOCK_PANIC_CHECK(lt) { \
- if ((lt)->region->hdr.panic) \
- return (DB_RUNRECOVERY); \
-}
-
-/*
- * The lock region consists of:
- * The DB_LOCKREGION structure (sizeof(DB_LOCKREGION)).
- * The conflict matrix of nmodes * nmodes bytes (nmodes * nmodes).
- * The hash table for object lookup (hashsize * sizeof(DB_OBJ *)).
- * The locks themselves (maxlocks * sizeof(struct __db_lock).
- * The objects being locked (maxlocks * sizeof(DB_OBJ)).
- * String space to represent the DBTs that are the objects being locked.
- */
-struct __db_lockregion {
- RLAYOUT hdr; /* Shared region header. */
- u_int32_t magic; /* lock magic number */
- u_int32_t version; /* version number */
- u_int32_t id; /* unique id generator */
- u_int32_t need_dd; /* flag for deadlock detector */
- u_int32_t detect; /* run dd on every conflict */
- SH_TAILQ_HEAD(lock_header) free_locks; /* free lock header */
- SH_TAILQ_HEAD(obj_header) free_objs; /* free obj header */
- u_int32_t maxlocks; /* maximum number of locks in table */
- u_int32_t table_size; /* size of hash table */
- u_int32_t nmodes; /* number of lock modes */
- u_int32_t numobjs; /* number of objects */
- u_int32_t nlockers; /* number of lockers */
- size_t increment; /* how much to grow region */
- size_t hash_off; /* offset of hash table */
- size_t mem_off; /* offset of memory region */
- size_t mem_bytes; /* number of bytes in memory region */
- u_int32_t nconflicts; /* number of lock conflicts */
- u_int32_t nrequests; /* number of lock gets */
- u_int32_t nreleases; /* number of lock puts */
- u_int32_t ndeadlocks; /* number of deadlocks */
-};
-
-/* Macros to lock/unlock the region. */
-#define LOCK_LOCKREGION(lt) \
- (void)__db_mutex_lock(&(lt)->region->hdr.lock, (lt)->reginfo.fd)
-#define UNLOCK_LOCKREGION(lt) \
- (void)__db_mutex_unlock(&(lt)->region->hdr.lock, (lt)->reginfo.fd)
-
-/*
- * Since we will be keeping DBTs in shared memory, we need the equivalent
- * of a DBT that will work in shared memory.
- */
-typedef struct __sh_dbt {
- u_int32_t size;
- ssize_t off;
-} SH_DBT;
-
-#define SH_DBT_PTR(p) ((void *)(((u_int8_t *)(p)) + (p)->off))
-
-struct __db_lockobj {
- SH_DBT lockobj; /* Identifies object locked. */
- SH_TAILQ_ENTRY links; /* Links for free list. */
- union {
- SH_TAILQ_HEAD(_wait) _waiters; /* List of waiting locks. */
- u_int32_t _dd_id; /* Deadlock detector id. */
- } wlinks;
- union {
- SH_LIST_HEAD(_held) _heldby; /* Locks held by this locker. */
- SH_TAILQ_HEAD(_hold) _holders; /* List of held locks. */
- } dlinks;
-#define DB_LOCK_OBJTYPE 1
-#define DB_LOCK_LOCKER 2
- /* Allocate room in the object to
- * hold typical DB lock structures
- * so that we do not have to
- * allocate them from shalloc. */
- u_int8_t objdata[sizeof(struct __db_ilock)];
- u_int8_t type; /* Real object or locker id. */
-};
-
-#define dd_id wlinks._dd_id
-#define waiters wlinks._waiters
-#define holders dlinks._holders
-#define heldby dlinks._heldby
-
-/*
- * The lock table is the per-process cookie returned from a lock_open call.
- */
-struct __db_locktab {
- DB_ENV *dbenv; /* Environment. */
- REGINFO reginfo; /* Region information. */
- DB_LOCKREGION *region; /* Address of shared memory region. */
- DB_HASHTAB *hashtab; /* Beginning of hash table. */
- void *mem; /* Beginning of string space. */
- u_int8_t *conflicts; /* Pointer to conflict matrix. */
-};
-
-/* Test for conflicts. */
-#define CONFLICTS(T, HELD, WANTED) \
- T->conflicts[HELD * T->region->nmodes + WANTED]
-
-/*
- * Resources in the lock region. Used to indicate which resource
- * is running low when we need to grow the region.
- */
-typedef enum {
- DB_LOCK_MEM, DB_LOCK_OBJ, DB_LOCK_LOCK
-} db_resource_t;
-
-struct __db_lock {
- /*
- * Wait on mutex to wait on lock. You reference your own mutex with
- * ID 0 and others reference your mutex with ID 1.
- */
- db_mutex_t mutex;
-
- u_int32_t holder; /* Who holds this lock. */
- SH_TAILQ_ENTRY links; /* Free or holder/waiter list. */
- SH_LIST_ENTRY locker_links; /* List of locks held by a locker. */
- u_int32_t refcount; /* Reference count the lock. */
- db_lockmode_t mode; /* What sort of lock. */
- ssize_t obj; /* Relative offset of object struct. */
- size_t txnoff; /* Offset of holding transaction. */
- db_status_t status; /* Status of this lock. */
-};
-
-/*
- * This is a serious layering violation. To support nested transactions, we
- * need to be able to tell that a lock is held by a transaction (as opposed to
- * some other locker) and to be able to traverse the parent/descendent chain.
- * In order to do this, each lock held by a transaction maintains a reference
- * to the shared memory transaction structure so it can be accessed during lock
- * promotion. As the structure is in shared memory, we cannot store a pointer
- * to it, so we use the offset within the region. As nothing lives at region
- * offset 0, we use that to indicate that there is no transaction associated
- * with the current lock.
- */
-#define TXN_IS_HOLDING(L) ((L)->txnoff != 0 /* INVALID_REG_OFFSET */)
-
-/*
- * We cannot return pointers to the user (else we cannot easily grow regions),
- * so we return offsets in the region. These must be converted to and from
- * regular pointers. Always use the macros below.
- */
-#define OFFSET_TO_LOCK(lt, off) \
- ((struct __db_lock *)((u_int8_t *)((lt)->region) + (off)))
-#define LOCK_TO_OFFSET(lt, lock) \
- ((size_t)((u_int8_t *)(lock) - (u_int8_t *)lt->region))
-#define OFFSET_TO_OBJ(lt, off) \
- ((DB_LOCKOBJ *)((u_int8_t *)((lt)->region) + (off)))
-#define OBJ_TO_OFFSET(lt, obj) \
- ((size_t)((u_int8_t *)(obj) - (u_int8_t *)lt->region))
-
-/*
- * The lock header contains the region structure and the conflict matrix.
- * Aligned to a large boundary because we don't know what the underlying
- * type of the hash table elements are.
- */
-#define LOCK_HASH_ALIGN 8
-#define LOCK_HEADER_SIZE(M) \
- ((size_t)(sizeof(DB_LOCKREGION) + ALIGN((M * M), LOCK_HASH_ALIGN)))
-
-/*
- * For the full region, we need to add the locks, the objects, the hash table
- * and the string space (which is 16 bytes per lock).
- */
-#define STRING_SIZE(N) (16 * N)
-
-#define LOCK_REGION_SIZE(M, N, H) \
- (ALIGN(LOCK_HEADER_SIZE(M) + \
- (H) * sizeof(DB_HASHTAB), MUTEX_ALIGNMENT) + \
- (N) * ALIGN(sizeof(struct __db_lock), MUTEX_ALIGNMENT) + \
- ALIGN((N) * sizeof(DB_LOCKOBJ), sizeof(size_t)) + \
- ALIGN(STRING_SIZE(N), sizeof(size_t)))
-
-#include "lock_ext.h"