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/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1996, 1997
* Sleepycat Software. All rights reserved.
*
* @(#)db_int.h.src 10.41 (Sleepycat) 1/8/98
*/
#ifndef _DB_INTERNAL_H_
#define _DB_INTERNAL_H_
#include "db.h" /* Standard DB include file. */
#include "queue.h"
#include "os_func.h"
#include "os_ext.h"
/*******************************************************
* General purpose constants and macros.
*******************************************************/
#define UINT16_T_MAX 0xffff /* Maximum 16 bit unsigned. */
#define UINT32_T_MAX 0xffffffff /* Maximum 32 bit unsigned. */
#define DB_MIN_PGSIZE 0x000200 /* Minimum page size. */
#define DB_MAX_PGSIZE 0x010000 /* Maximum page size. */
#define DB_MINCACHE 10 /* Minimum cached pages */
#define MEGABYTE 1048576
/*
* If we are unable to determine the underlying filesystem block size, use
* 8K on the grounds that most OS's use less than 8K as their VM page size.
*/
#define DB_DEF_IOSIZE (8 * 1024)
/*
* Aligning items to particular sizes or in pages or memory. ALIGNP is a
* separate macro, as we've had to cast the pointer to different integral
* types on different architectures.
*
* We cast pointers into unsigned longs when manipulating them because C89
* guarantees that u_long is the largest available integral type and further,
* to never generate overflows. However, neither C89 or C9X requires that
* any integer type be large enough to hold a pointer, although C9X created
* the intptr_t type, which is guaranteed to hold a pointer but may or may
* not exist. At some point in the future, we should test for intptr_t and
* use it where available.
*/
#undef ALIGNTYPE
#define ALIGNTYPE u_long
#undef ALIGNP
#define ALIGNP(value, bound) ALIGN((ALIGNTYPE)value, bound)
#undef ALIGN
#define ALIGN(value, bound) (((value) + (bound) - 1) & ~((bound) - 1))
/*
* There are several on-page structures that are declared to have a number of
* fields followed by a variable length array of items. The structure size
* without including the variable length array or the address of the first of
* those elements can be found using SSZ.
*
* This macro can also be used to find the offset of a structure element in a
* structure. This is used in various places to copy structure elements from
* unaligned memory references, e.g., pointers into a packed page.
*
* There are two versions because compilers object if you take the address of
* an array.
*/
#undef SSZ
#define SSZ(name, field) ((int)&(((name *)0)->field))
#undef SSZA
#define SSZA(name, field) ((int)&(((name *)0)->field[0]))
/* Macros to return per-process address, offsets based on shared regions. */
#define R_ADDR(base, offset) ((void *)((u_int8_t *)((base)->addr) + offset))
#define R_OFFSET(base, p) ((u_int8_t *)(p) - (u_int8_t *)(base)->addr)
/* Free and free-string macros that overwrite memory during debugging. */
#ifdef DEBUG
#undef FREE
#define FREE(p, len) { \
memset(p, 0xff, len); \
__db_free(p); \
}
#undef FREES
#define FREES(p) { \
FREE(p, strlen(p)); \
}
#else
#undef FREE
#define FREE(p, len) { \
__db_free(p); \
}
#undef FREES
#define FREES(p) { \
__db_free(p); \
}
#endif
/* Structure used to print flag values. */
typedef struct __fn {
u_int32_t mask; /* Flag value. */
const char *name; /* Flag name. */
} FN;
/* Set, clear and test flags. */
#define F_SET(p, f) (p)->flags |= (f)
#define F_CLR(p, f) (p)->flags &= ~(f)
#define F_ISSET(p, f) ((p)->flags & (f))
#define LF_SET(f) (flags |= (f))
#define LF_CLR(f) (flags &= ~(f))
#define LF_ISSET(f) (flags & (f))
/* Display separator string. */
#undef DB_LINE
#define DB_LINE "=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-="
/* Unused, or not-used-yet variable. "Shut that bloody compiler up!" */
#define COMPQUIET(n, v) (n) = (v)
/*******************************************************
* Files.
*******************************************************/
#ifndef MAXPATHLEN /* Maximum path length. */
#ifdef PATH_MAX
#define MAXPATHLEN PATH_MAX
#else
#define MAXPATHLEN 1024
#endif
#endif
#define PATH_DOT "." /* Current working directory. */
#define PATH_SEPARATOR "/" /* Path separator character. */
#ifndef S_IRUSR /* UNIX specific file permissions. */
#define S_IRUSR 0000400 /* R for owner */
#define S_IWUSR 0000200 /* W for owner */
#define S_IRGRP 0000040 /* R for group */
#define S_IWGRP 0000020 /* W for group */
#define S_IROTH 0000004 /* R for other */
#define S_IWOTH 0000002 /* W for other */
#endif
#ifndef S_ISDIR /* UNIX specific: directory test. */
#define S_ISDIR(m) ((m & 0170000) == 0040000)
#endif
/*******************************************************
* Mutex support.
*******************************************************/
typedef unsigned char tsl_t;
/*
* !!!
* Various systems require different alignments for mutexes (the worst we've
* seen so far is 16-bytes on some HP architectures). The mutex (tsl_t) must
* be first in the db_mutex_t structure, which must itself be first in the
* region. This ensures the alignment is as returned by mmap(2), which should
* be sufficient. All other mutex users must ensure proper alignment locally.
*/
#define MUTEX_ALIGNMENT 1
/*
* The offset of a mutex in memory.
*
* !!!
* Not an off_t, so backing file offsets MUST be less than 4Gb. See the
* off field of the db_mutex_t as well.
*/
#define MUTEX_LOCK_OFFSET(a, b) ((u_int32_t)((u_int8_t *)b - (u_int8_t *)a))
typedef struct _db_mutex_t {
#ifdef HAVE_SPINLOCKS
tsl_t tsl_resource; /* Resource test and set. */
#ifdef DEBUG
u_long pid; /* Lock holder: 0 or process pid. */
#endif
#else
u_int32_t off; /* Backing file offset. */
u_long pid; /* Lock holder: 0 or process pid. */
#endif
u_int32_t spins; /* Spins before block. */
u_int32_t mutex_set_wait; /* Granted after wait. */
u_int32_t mutex_set_nowait; /* Granted without waiting. */
} db_mutex_t;
#include "mutex_ext.h"
/*******************************************************
* Access methods.
*******************************************************/
/* Lock/unlock a DB thread. */
#define DB_THREAD_LOCK(dbp) \
(F_ISSET(dbp, DB_AM_THREAD) ? \
__db_mutex_lock((db_mutex_t *)(dbp)->mutexp, -1) : 0)
#define DB_THREAD_UNLOCK(dbp) \
(F_ISSET(dbp, DB_AM_THREAD) ? \
__db_mutex_unlock((db_mutex_t *)(dbp)->mutexp, -1) : 0)
/* Btree/recno local statistics structure. */
struct __db_bt_lstat; typedef struct __db_bt_lstat DB_BTREE_LSTAT;
struct __db_bt_lstat {
u_int32_t bt_freed; /* Pages freed for reuse. */
u_int32_t bt_pfxsaved; /* Bytes saved by prefix compression. */
u_int32_t bt_split; /* Total number of splits. */
u_int32_t bt_rootsplit; /* Root page splits. */
u_int32_t bt_fastsplit; /* Fast splits. */
u_int32_t bt_added; /* Items added. */
u_int32_t bt_deleted; /* Items deleted. */
u_int32_t bt_get; /* Items retrieved. */
u_int32_t bt_cache_hit; /* Hits in fast-insert code. */
u_int32_t bt_cache_miss; /* Misses in fast-insert code. */
};
/*******************************************************
* Environment.
*******************************************************/
/* Type passed to __db_appname(). */
typedef enum {
DB_APP_NONE=0, /* No type (region). */
DB_APP_DATA, /* Data file. */
DB_APP_LOG, /* Log file. */
DB_APP_TMP /* Temporary file. */
} APPNAME;
/*******************************************************
* Regions.
*******************************************************/
/*
* The shared memory regions share an initial structure so that the general
* region code can handle races between the region being deleted and other
* processes waiting on the region mutex.
*
* !!!
* Note, the mutex must be the first entry in the region; see comment above.
*/
typedef struct _rlayout {
db_mutex_t lock; /* Region mutex. */
u_int32_t refcnt; /* Region reference count. */
size_t size; /* Region length. */
int majver; /* Major version number. */
int minver; /* Minor version number. */
int patch; /* Patch version number. */
#define DB_R_DELETED 0x01 /* Region was deleted. */
u_int32_t flags;
} RLAYOUT;
/*******************************************************
* Mpool.
*******************************************************/
/*
* File types for DB access methods. Negative numbers are reserved to DB.
*/
#define DB_FTYPE_BTREE -1 /* Btree. */
#define DB_FTYPE_HASH -2 /* Hash. */
/* Structure used as the DB pgin/pgout pgcookie. */
typedef struct __dbpginfo {
size_t db_pagesize; /* Underlying page size. */
int needswap; /* If swapping required. */
} DB_PGINFO;
/*******************************************************
* Log.
*******************************************************/
/* Initialize an LSN to 'zero'. */
#define ZERO_LSN(LSN) { \
(LSN).file = 0; \
(LSN).offset = 0; \
}
/* Return 1 if LSN is a 'zero' lsn, otherwise return 0. */
#define IS_ZERO_LSN(LSN) ((LSN).file == 0)
/* Test if we need to log a change. */
#define DB_LOGGING(dbp) \
(F_ISSET(dbp, DB_AM_LOGGING) && !F_ISSET(dbp, DB_AM_RECOVER))
#ifdef DEBUG
/*
* Debugging macro to log operations.
* If DEBUG_WOP is defined, log operations that modify the database.
* If DEBUG_ROP is defined, log operations that read the database.
*
* D dbp
* T txn
* O operation (string)
* K key
* A data
* F flags
*/
#define LOG_OP(D, T, O, K, A, F) { \
DB_LSN _lsn; \
DBT _op; \
if (DB_LOGGING((D))) { \
memset(&_op, 0, sizeof(_op)); \
_op.data = O; \
_op.size = strlen(O) + 1; \
(void)__db_debug_log((D)->dbenv->lg_info, \
T, &_lsn, 0, &_op, (D)->log_fileid, K, A, F); \
} \
}
#ifdef DEBUG_ROP
#define DEBUG_LREAD(D, T, O, K, A, F) LOG_OP(D, T, O, K, A, F)
#else
#define DEBUG_LREAD(D, T, O, K, A, F)
#endif
#ifdef DEBUG_WOP
#define DEBUG_LWRITE(D, T, O, K, A, F) LOG_OP(D, T, O, K, A, F)
#else
#define DEBUG_LWRITE(D, T, O, K, A, F)
#endif
#else
#define DEBUG_LREAD(D, T, O, K, A, F)
#define DEBUG_LWRITE(D, T, O, K, A, F)
#endif /* DEBUG */
/*******************************************************
* Transactions and recovery.
*******************************************************/
/*
* Out of band value for a lock. The locks are returned to callers as offsets
* into the lock regions. Since the RLAYOUT structure begins all regions, an
* offset of 0 is guaranteed not to be a valid lock.
*/
#define LOCK_INVALID 0
/* The structure allocated for every transaction. */
struct __db_txn {
DB_TXNMGR *mgrp; /* Pointer to transaction manager. */
DB_TXN *parent; /* Pointer to transaction's parent. */
DB_LSN last_lsn; /* Lsn of last log write. */
u_int32_t txnid; /* Unique transaction id. */
size_t off; /* Detail structure within region. */
TAILQ_ENTRY(__db_txn) links;
};
#endif /* !_DB_INTERNAL_H_ */
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