From f145fa326b29ee6452e909d3dfa8d03df6495aca Mon Sep 17 00:00:00 2001 From: unknown Date: Thu, 18 Sep 2014 19:07:23 -0700 Subject: [PATCH] Introduce threadskv7 that includes atomic insert of a set of keys with values --- README.md | 4 +- threadskv7.c | 3055 ++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 3058 insertions(+), 1 deletion(-) create mode 100644 threadskv7.c diff --git a/README.md b/README.md index 338a020..16adcf3 100644 --- a/README.md +++ b/README.md @@ -1,7 +1,7 @@ Btree-source-code ================= -A working project for High-concurrency B-tree source code in C. You probably want to download threadskv6.c for the latest developement version. +A working project for High-concurrency B-tree source code in C. You probably want to download threadskv7.c for the latest developement version. Here are files in the btree source code: @@ -31,6 +31,8 @@ threadskv5.c Multi-Threaded/Multi-Process based on threadskv4b that supports bi- threadskv6.c Multi-Threaded/Single-Process with traditional buffer pool manager using the swap device. Based on threadskv5 and btree2u. +threadskv7.c Multi-Threaded/Single-Process with atomic add of a set of keys + Compilation is achieved on linux or Windows by: gcc -D STANDALONE threads2h.c -lpthread diff --git a/threadskv7.c b/threadskv7.c new file mode 100644 index 0000000..86d7300 --- /dev/null +++ b/threadskv7.c @@ -0,0 +1,3055 @@ +// btree version threadskv6 sched_yield version +// with reworked bt_deletekey code, +// phase-fair reader writer lock, +// librarian page split code, +// duplicate key management +// bi-directional cursors +// traditional buffer pool manager +// and atomic key insert + +// 17 SEP 2014 + +// author: karl malbrain, malbrain@cal.berkeley.edu + +/* +This work, including the source code, documentation +and related data, is placed into the public domain. + +The orginal author is Karl Malbrain. + +THIS SOFTWARE IS PROVIDED AS-IS WITHOUT WARRANTY +OF ANY KIND, NOT EVEN THE IMPLIED WARRANTY OF +MERCHANTABILITY. THE AUTHOR OF THIS SOFTWARE, +ASSUMES _NO_ RESPONSIBILITY FOR ANY CONSEQUENCE +RESULTING FROM THE USE, MODIFICATION, OR +REDISTRIBUTION OF THIS SOFTWARE. +*/ + +// Please see the project home page for documentation +// code.google.com/p/high-concurrency-btree + +#define _FILE_OFFSET_BITS 64 +#define _LARGEFILE64_SOURCE + +#ifdef linux +#define _GNU_SOURCE +#endif + +#ifdef unix +#include +#include +#include +#include +#include +#include +#include +#include +#else +#define WIN32_LEAN_AND_MEAN +#include +#include +#include +#include +#include +#include +#include +#endif + +#include +#include +#include + +typedef unsigned long long uid; + +#ifndef unix +typedef unsigned long long off64_t; +typedef unsigned short ushort; +typedef unsigned int uint; +#endif + +#define BT_ro 0x6f72 // ro +#define BT_rw 0x7772 // rw + +#define BT_maxbits 24 // maximum page size in bits +#define BT_minbits 9 // minimum page size in bits +#define BT_minpage (1 << BT_minbits) // minimum page size +#define BT_maxpage (1 << BT_maxbits) // maximum page size + +// BTree page number constants +#define ALLOC_page 0 // allocation page +#define ROOT_page 1 // root of the btree +#define LEAF_page 2 // first page of leaves + +// Number of levels to create in a new BTree + +#define MIN_lvl 2 + +// maximum number of keys to insert atomically in one call + +#define MAX_atomic 256 + +#define BT_maxkey 255 // maximum number of bytes in a key +#define BT_keyarray (BT_maxkey + sizeof(BtKey)) + +/* +There are five lock types for each node in three independent sets: +1. (set 1) AccessIntent: Sharable. Going to Read the node. Incompatible with NodeDelete. +2. (set 1) NodeDelete: Exclusive. About to release the node. Incompatible with AccessIntent. +3. (set 2) ReadLock: Sharable. Read the node. Incompatible with WriteLock. +4. (set 2) WriteLock: Exclusive. Modify the node. Incompatible with ReadLock and other WriteLocks. +5. (set 3) ParentModification: Exclusive. Change the node's parent keys. Incompatible with another ParentModification. +*/ + +typedef enum{ + BtLockAccess, + BtLockDelete, + BtLockRead, + BtLockWrite, + BtLockParent +} BtLock; + +// definition for phase-fair reader/writer lock implementation + +typedef struct { + ushort rin[1]; + ushort rout[1]; + ushort ticket[1]; + ushort serving[1]; +} RWLock; + +#define PHID 0x1 +#define PRES 0x2 +#define MASK 0x3 +#define RINC 0x4 + +// definition for spin latch implementation + +// exclusive is set for write access +// share is count of read accessors +// grant write lock when share == 0 + +volatile typedef struct { + uint exclusive:1; + uint pending:1; + uint share:30; +} BtSpinLatch; + +#define XCL 1 +#define PEND 2 +#define BOTH 3 +#define SHARE 4 + +// The key structure occupies space at the upper end of +// each page. It's a length byte followed by the key +// bytes. + +typedef struct { + unsigned char len; // this can be changed to a ushort or uint + unsigned char key[0]; +} BtKey; + +// the value structure also occupies space at the upper +// end of the page. Each key is immediately followed by a value. + +typedef struct { + unsigned char len; // this can be changed to a ushort or uint + unsigned char value[0]; +} BtVal; + +// hash table entries + +typedef struct { + uint slot; // Latch table entry at head of chain + BtSpinLatch latch[1]; +} BtHashEntry; + +// latch manager table structure + +typedef struct { + uid page_no; // latch set page number + RWLock readwr[1]; // read/write page lock + RWLock access[1]; // Access Intent/Page delete + RWLock parent[1]; // Posting of fence key in parent + uint slot; // entry slot in latch table + uint next; // next entry in hash table chain + uint prev; // prev entry in hash table chain + volatile ushort pin; // number of outstanding threads + ushort dirty:1; // page in cache is dirty +} BtLatchSet; + +// lock manager table structure + +typedef struct { + RWLock readwr[1]; // read/write key lock + uint next; + uint prev; + uint pin; // count of readers waiting + uint hashidx; // hash idx for entry + unsigned char key[BT_keyarray]; +} BtLockSet; + +// Define the length of the page record numbers + +#define BtId 6 + +// Page key slot definition. + +// Keys are marked dead, but remain on the page until +// it cleanup is called. The fence key (highest key) for +// a leaf page is always present, even after cleanup. + +// Slot types + +// In addition to the Unique keys that occupy slots +// there are Librarian and Duplicate key +// slots occupying the key slot array. + +// The Librarian slots are dead keys that +// serve as filler, available to add new Unique +// or Dup slots that are inserted into the B-tree. + +// The Duplicate slots have had their key bytes extended +// by 6 bytes to contain a binary duplicate key uniqueifier. + +typedef enum { + Unique, + Librarian, + Duplicate +} BtSlotType; + +typedef struct { + uint off:BT_maxbits; // page offset for key start + uint type:3; // type of slot + uint dead:1; // set for deleted slot +} BtSlot; + +// The first part of an index page. +// It is immediately followed +// by the BtSlot array of keys. + +// note that this structure size +// must be a multiple of 8 bytes +// in order to place dups correctly. + +typedef struct BtPage_ { + uint cnt; // count of keys in page + uint act; // count of active keys + uint min; // next key offset + uint garbage; // page garbage in bytes + unsigned char bits:7; // page size in bits + unsigned char free:1; // page is on free chain + unsigned char lvl:7; // level of page + unsigned char kill:1; // page is being deleted + unsigned char left[BtId]; // page number to left + unsigned char filler[2]; // padding to multiple of 8 + unsigned char right[BtId]; // page number to right +} *BtPage; + +// The loadpage interface object + +typedef struct { + uid page_no; // current page number + BtPage page; // current page pointer + BtLatchSet *latch; // current page latch set +} BtPageSet; + +// structure for latch manager on ALLOC_page + +typedef struct { + struct BtPage_ alloc[1]; // next page_no in right ptr + unsigned long long dups[1]; // global duplicate key uniqueifier + unsigned char chain[BtId]; // head of free page_nos chain +} BtPageZero; + +// The object structure for Btree access + +typedef struct { + uint page_size; // page size + uint page_bits; // page size in bits +#ifdef unix + int idx; +#else + HANDLE idx; +#endif + BtPageZero *pagezero; // mapped allocation page + BtSpinLatch alloclatch[1]; // allocation area lite latch + uint latchdeployed; // highest number of pool entries deployed + uint nlatchpage; // number of latch & lock & pool pages + uint latchtotal; // number of page latch entries + uint latchhash; // number of latch hash table slots + uint latchvictim; // next latch entry to examine + BtHashEntry *hashtable; // the anonymous mapping buffer pool + BtLatchSet *latchsets; // mapped latch set from latch pages + unsigned char *pagepool; // mapped to the buffer pool pages + uint lockhash; // number of lock hash table slots + uint lockfree; // next available lock table entry + BtSpinLatch locklatch[1]; // lock manager free chain latch + BtHashEntry *hashlock; // the lock manager hash table + BtLockSet *locktable; // the lock manager key table +#ifndef unix + HANDLE halloc; // allocation handle + HANDLE hpool; // buffer pool handle +#endif +} BtMgr; + +typedef struct { + BtMgr *mgr; // buffer manager for thread + BtPage cursor; // cached frame for start/next (never mapped) + BtPage frame; // spare frame for the page split (never mapped) + uid cursor_page; // current cursor page number + unsigned char *mem; // frame, cursor, page memory buffer + unsigned char key[BT_keyarray]; // last found complete key + int found; // last delete or insert was found + int err; // last error + int reads, writes; // number of reads and writes from the btree +} BtDb; + +typedef enum { + BTERR_ok = 0, + BTERR_struct, + BTERR_ovflw, + BTERR_lock, + BTERR_map, + BTERR_read, + BTERR_wrt, + BTERR_hash +} BTERR; + +#define CLOCK_bit 0x8000 + +// B-Tree functions +extern void bt_close (BtDb *bt); +extern BtDb *bt_open (BtMgr *mgr); +extern BTERR bt_insertkey (BtDb *bt, unsigned char *key, uint len, uint lvl, void *value, uint vallen, int unique); +extern BTERR bt_deletekey (BtDb *bt, unsigned char *key, uint len, uint lvl); +extern int bt_findkey (BtDb *bt, unsigned char *key, uint keylen, unsigned char *value, uint valmax); +extern BtKey *bt_foundkey (BtDb *bt); +extern uint bt_startkey (BtDb *bt, unsigned char *key, uint len); +extern uint bt_nextkey (BtDb *bt, uint slot); + +// manager functions +extern BtMgr *bt_mgr (char *name, uint bits, uint poolsize, uint locksize); +void bt_mgrclose (BtMgr *mgr); + +// Helper functions to return slot values +// from the cursor page. + +extern BtKey *bt_key (BtDb *bt, uint slot); +extern BtVal *bt_val (BtDb *bt, uint slot); + +// The page is allocated from low and hi ends. +// The key slots are allocated from the bottom, +// while the text and value of the key +// are allocated from the top. When the two +// areas meet, the page is split into two. + +// A key consists of a length byte, two bytes of +// index number (0 - 65535), and up to 253 bytes +// of key value. + +// Associated with each key is a value byte string +// containing any value desired. + +// The b-tree root is always located at page 1. +// The first leaf page of level zero is always +// located on page 2. + +// The b-tree pages are linked with next +// pointers to facilitate enumerators, +// and provide for concurrency. + +// When to root page fills, it is split in two and +// the tree height is raised by a new root at page +// one with two keys. + +// Deleted keys are marked with a dead bit until +// page cleanup. The fence key for a leaf node is +// always present + +// To achieve maximum concurrency one page is locked at a time +// as the tree is traversed to find leaf key in question. The right +// page numbers are used in cases where the page is being split, +// or consolidated. + +// Page 0 is dedicated to lock for new page extensions, +// and chains empty pages together for reuse. It also +// contains the latch manager hash table. + +// The ParentModification lock on a node is obtained to serialize posting +// or changing the fence key for a node. + +// Empty pages are chained together through the ALLOC page and reused. + +// Access macros to address slot and key values from the page +// Page slots use 1 based indexing. + +#define slotptr(page, slot) (((BtSlot *)(page+1)) + (slot-1)) +#define keyptr(page, slot) ((BtKey*)((unsigned char*)(page) + slotptr(page, slot)->off)) +#define valptr(page, slot) ((BtVal*)(keyptr(page,slot)->key + keyptr(page,slot)->len)) + +void bt_putid(unsigned char *dest, uid id) +{ +int i = BtId; + + while( i-- ) + dest[i] = (unsigned char)id, id >>= 8; +} + +uid bt_getid(unsigned char *src) +{ +uid id = 0; +int i; + + for( i = 0; i < BtId; i++ ) + id <<= 8, id |= *src++; + + return id; +} + +uid bt_newdup (BtDb *bt) +{ +#ifdef unix + return __sync_fetch_and_add (bt->mgr->pagezero->dups, 1) + 1; +#else + return _InterlockedIncrement64(bt->mgr->pagezero->dups, 1); +#endif +} + +// Phase-Fair reader/writer lock implementation + +void WriteLock (RWLock *lock) +{ +ushort w, r, tix; + +#ifdef unix + tix = __sync_fetch_and_add (lock->ticket, 1); +#else + tix = _InterlockedExchangeAdd16 (lock->ticket, 1); +#endif + // wait for our ticket to come up + + while( tix != lock->serving[0] ) +#ifdef unix + sched_yield(); +#else + SwitchToThread (); +#endif + + w = PRES | (tix & PHID); +#ifdef unix + r = __sync_fetch_and_add (lock->rin, w); +#else + r = _InterlockedExchangeAdd16 (lock->rin, w); +#endif + while( r != *lock->rout ) +#ifdef unix + sched_yield(); +#else + SwitchToThread(); +#endif +} + +void WriteRelease (RWLock *lock) +{ +#ifdef unix + __sync_fetch_and_and (lock->rin, ~MASK); +#else + _InterlockedAnd16 (lock->rin, ~MASK); +#endif + lock->serving[0]++; +} + +void ReadLock (RWLock *lock) +{ +ushort w; +#ifdef unix + w = __sync_fetch_and_add (lock->rin, RINC) & MASK; +#else + w = _InterlockedExchangeAdd16 (lock->rin, RINC) & MASK; +#endif + if( w ) + while( w == (*lock->rin & MASK) ) +#ifdef unix + sched_yield (); +#else + SwitchToThread (); +#endif +} + +void ReadRelease (RWLock *lock) +{ +#ifdef unix + __sync_fetch_and_add (lock->rout, RINC); +#else + _InterlockedExchangeAdd16 (lock->rout, RINC); +#endif +} + +// Spin Latch Manager + +// wait until write lock mode is clear +// and add 1 to the share count + +void bt_spinreadlock(BtSpinLatch *latch) +{ +uint prev; + + do { +#ifdef unix + prev = __sync_fetch_and_add ((uint *)latch, SHARE); +#else + prev = _InterlockedExchangeAdd((uint *)latch, SHARE); +#endif + // see if exclusive request is granted or pending + + if( !(prev & BOTH) ) + return; +#ifdef unix + prev = __sync_fetch_and_add ((uint *)latch, -SHARE); +#else + prev = _InterlockedExchangeAdd((uint *)latch, -SHARE); +#endif +#ifdef unix + } while( sched_yield(), 1 ); +#else + } while( SwitchToThread(), 1 ); +#endif +} + +// wait for other read and write latches to relinquish + +void bt_spinwritelock(BtSpinLatch *latch) +{ +uint prev; + + do { +#ifdef unix + prev = __sync_fetch_and_or((uint *)latch, PEND | XCL); +#else + prev = _InterlockedOr((uint *)latch, PEND | XCL); +#endif + if( !(prev & XCL) ) + if( !(prev & ~BOTH) ) + return; + else +#ifdef unix + __sync_fetch_and_and ((uint *)latch, ~XCL); +#else + _InterlockedAnd((uint *)latch, ~XCL); +#endif +#ifdef unix + } while( sched_yield(), 1 ); +#else + } while( SwitchToThread(), 1 ); +#endif +} + +// try to obtain write lock + +// return 1 if obtained, +// 0 otherwise + +int bt_spinwritetry(BtSpinLatch *latch) +{ +uint prev; + +#ifdef unix + prev = __sync_fetch_and_or((uint *)latch, XCL); +#else + prev = _InterlockedOr((uint *)latch, XCL); +#endif + // take write access if all bits are clear + + if( !(prev & XCL) ) + if( !(prev & ~BOTH) ) + return 1; + else +#ifdef unix + __sync_fetch_and_and ((uint *)latch, ~XCL); +#else + _InterlockedAnd((uint *)latch, ~XCL); +#endif + return 0; +} + +// clear write mode + +void bt_spinreleasewrite(BtSpinLatch *latch) +{ +#ifdef unix + __sync_fetch_and_and((uint *)latch, ~BOTH); +#else + _InterlockedAnd((uint *)latch, ~BOTH); +#endif +} + +// decrement reader count + +void bt_spinreleaseread(BtSpinLatch *latch) +{ +#ifdef unix + __sync_fetch_and_add((uint *)latch, -SHARE); +#else + _InterlockedExchangeAdd((uint *)latch, -SHARE); +#endif +} + +// read page from permanent location in Btree file + +BTERR bt_readpage (BtMgr *mgr, BtPage page, uid page_no) +{ +off64_t off = page_no << mgr->page_bits; + +#ifdef unix + if( pread (mgr->idx, page, mgr->page_size, page_no << mgr->page_bits) < mgr->page_size ) { + fprintf (stderr, "Unable to read page %.8x errno = %d\n", page_no, errno); + return BTERR_read; + } +#else +OVERLAPPED ovl[1]; +uint amt[1]; + + memset (ovl, 0, sizeof(OVERLAPPED)); + ovl->Offset = off; + ovl->OffsetHigh = off >> 32; + + if( !ReadFile(mgr->idx, page, mgr->page_size, amt, ovl)) { + fprintf (stderr, "Unable to read page %.8x GetLastError = %d\n", page_no, GetLastError()); + return BTERR_read; + } + if( *amt < mgr->page_size ) { + fprintf (stderr, "Unable to read page %.8x GetLastError = %d\n", page_no, GetLastError()); + return BTERR_read; + } +#endif + return 0; +} + +// write page to permanent location in Btree file +// clear the dirty bit + +BTERR bt_writepage (BtMgr *mgr, BtPage page, uid page_no) +{ +off64_t off = page_no << mgr->page_bits; + +#ifdef unix + if( pwrite(mgr->idx, page, mgr->page_size, off) < mgr->page_size ) + return BTERR_wrt; +#else +OVERLAPPED ovl[1]; +uint amt[1]; + + memset (ovl, 0, sizeof(OVERLAPPED)); + ovl->Offset = off; + ovl->OffsetHigh = off >> 32; + + if( !WriteFile(mgr->idx, page, mgr->page_size, amt, ovl) ) + return BTERR_wrt; + + if( *amt < mgr->page_size ) + return BTERR_wrt; +#endif + return 0; +} + +// link latch table entry into head of latch hash table + +BTERR bt_latchlink (BtDb *bt, uint hashidx, uint slot, uid page_no, uint loadit) +{ +BtPage page = (BtPage)(((uid)slot << bt->mgr->page_bits) + bt->mgr->pagepool); +BtLatchSet *latch = bt->mgr->latchsets + slot; + + if( latch->next = bt->mgr->hashtable[hashidx].slot ) + bt->mgr->latchsets[latch->next].prev = slot; + + bt->mgr->hashtable[hashidx].slot = slot; + latch->page_no = page_no; + latch->slot = slot; + latch->prev = 0; + latch->pin = 1; + + if( loadit ) + if( bt->err = bt_readpage (bt->mgr, page, page_no) ) + return bt->err; + else + bt->reads++; + + return bt->err = 0; +} + +// set CLOCK bit in latch +// decrement pin count + +void bt_unpinlatch (BtLatchSet *latch) +{ +#ifdef unix + if( ~latch->pin & CLOCK_bit ) + __sync_fetch_and_or(&latch->pin, CLOCK_bit); + __sync_fetch_and_add(&latch->pin, -1); +#else + if( ~latch->pin & CLOCK_bit ) + _InterlockedOr16 (&latch->pin, CLOCK_bit); + _InterlockedDecrement16 (&latch->pin); +#endif +} + +// return the btree cached page address + +BtPage bt_mappage (BtDb *bt, BtLatchSet *latch) +{ +BtPage page = (BtPage)(((uid)latch->slot << bt->mgr->page_bits) + bt->mgr->pagepool); + + return page; +} + +// find existing latchset or inspire new one +// return with latchset pinned + +BtLatchSet *bt_pinlatch (BtDb *bt, uid page_no, uint loadit) +{ +uint hashidx = page_no % bt->mgr->latchhash; +BtLatchSet *latch; +uint slot, idx; +uint lvl, cnt; +off64_t off; +uint amt[1]; +BtPage page; + + // try to find our entry + + bt_spinwritelock(bt->mgr->hashtable[hashidx].latch); + + if( slot = bt->mgr->hashtable[hashidx].slot ) do + { + latch = bt->mgr->latchsets + slot; + if( page_no == latch->page_no ) + break; + } while( slot = latch->next ); + + // found our entry + // increment clock + + if( slot ) { + latch = bt->mgr->latchsets + slot; +#ifdef unix + __sync_fetch_and_add(&latch->pin, 1); +#else + _InterlockedIncrement16 (&latch->pin); +#endif + bt_spinreleasewrite(bt->mgr->hashtable[hashidx].latch); + return latch; + } + + // see if there are any unused pool entries +#ifdef unix + slot = __sync_fetch_and_add (&bt->mgr->latchdeployed, 1) + 1; +#else + slot = _InterlockedIncrement (&bt->mgr->latchdeployed); +#endif + + if( slot < bt->mgr->latchtotal ) { + latch = bt->mgr->latchsets + slot; + if( bt_latchlink (bt, hashidx, slot, page_no, loadit) ) + return NULL; + bt_spinreleasewrite (bt->mgr->hashtable[hashidx].latch); + return latch; + } + +#ifdef unix + __sync_fetch_and_add (&bt->mgr->latchdeployed, -1); +#else + _InterlockedDecrement (&bt->mgr->latchdeployed); +#endif + // find and reuse previous entry on victim + + while( 1 ) { +#ifdef unix + slot = __sync_fetch_and_add(&bt->mgr->latchvictim, 1); +#else + slot = _InterlockedIncrement (&bt->mgr->latchvictim) - 1; +#endif + // try to get write lock on hash chain + // skip entry if not obtained + // or has outstanding pins + + slot %= bt->mgr->latchtotal; + + if( !slot ) + continue; + + latch = bt->mgr->latchsets + slot; + idx = latch->page_no % bt->mgr->latchhash; + + // see we are on same chain as hashidx + + if( idx == hashidx ) + continue; + + if( !bt_spinwritetry (bt->mgr->hashtable[idx].latch) ) + continue; + + // skip this slot if it is pinned + // or the CLOCK bit is set + + if( latch->pin ) { + if( latch->pin & CLOCK_bit ) { +#ifdef unix + __sync_fetch_and_and(&latch->pin, ~CLOCK_bit); +#else + _InterlockedAnd16 (&latch->pin, ~CLOCK_bit); +#endif + } + bt_spinreleasewrite (bt->mgr->hashtable[idx].latch); + continue; + } + + // update permanent page area in btree from buffer pool + + page = (BtPage)(((uid)slot << bt->mgr->page_bits) + bt->mgr->pagepool); + + if( latch->dirty ) + if( bt->err = bt_writepage (bt->mgr, page, latch->page_no) ) + return NULL; + else + latch->dirty = 0, bt->writes++; + + // unlink our available slot from its hash chain + + if( latch->prev ) + bt->mgr->latchsets[latch->prev].next = latch->next; + else + bt->mgr->hashtable[idx].slot = latch->next; + + if( latch->next ) + bt->mgr->latchsets[latch->next].prev = latch->prev; + + bt_spinreleasewrite (bt->mgr->hashtable[idx].latch); + + if( bt_latchlink (bt, hashidx, slot, page_no, loadit) ) + return NULL; + + bt_spinreleasewrite (bt->mgr->hashtable[hashidx].latch); + return latch; + } +} + +void bt_mgrclose (BtMgr *mgr) +{ +BtLatchSet *latch; +uint num = 0; +BtPage page; +uint slot; + + // flush dirty pool pages to the btree + + for( slot = 1; slot <= mgr->latchdeployed; slot++ ) { + page = (BtPage)(((uid)slot << mgr->page_bits) + mgr->pagepool); + latch = mgr->latchsets + slot; + + if( latch->dirty ) { + bt_writepage(mgr, page, latch->page_no); + latch->dirty = 0, num++; + } +// madvise (page, mgr->page_size, MADV_DONTNEED); + } + + fprintf(stderr, "%d buffer pool pages flushed\n", num); + +#ifdef unix + munmap (mgr->hashtable, (uid)mgr->nlatchpage << mgr->page_bits); + munmap (mgr->pagezero, mgr->page_size); +#else + FlushViewOfFile(mgr->pagezero, 0); + UnmapViewOfFile(mgr->pagezero); + UnmapViewOfFile(mgr->hashtable); + CloseHandle(mgr->halloc); + CloseHandle(mgr->hpool); +#endif +#ifdef unix + close (mgr->idx); + free (mgr); +#else + FlushFileBuffers(mgr->idx); + CloseHandle(mgr->idx); + GlobalFree (mgr); +#endif +} + +// close and release memory + +void bt_close (BtDb *bt) +{ +#ifdef unix + if( bt->mem ) + free (bt->mem); +#else + if( bt->mem) + VirtualFree (bt->mem, 0, MEM_RELEASE); +#endif + free (bt); +} + +// open/create new btree buffer manager + +// call with file_name, BT_openmode, bits in page size (e.g. 16), +// size of page pool (e.g. 262144) and number of lock table entries. + +BtMgr *bt_mgr (char *name, uint bits, uint nodemax, uint lockmax) +{ +uint lvl, attr, last, slot, idx; +unsigned char value[BtId]; +int flag, initit = 0; +BtPageZero *pagezero; +off64_t size; +uint amt[1]; +BtMgr* mgr; +BtKey* key; +BtVal *val; + + // determine sanity of page size and buffer pool + + if( bits > BT_maxbits ) + bits = BT_maxbits; + else if( bits < BT_minbits ) + bits = BT_minbits; + + if( nodemax < 16 ) { + fprintf(stderr, "Buffer pool too small: %d\n", nodemax); + return NULL; + } + +#ifdef unix + mgr = calloc (1, sizeof(BtMgr)); + + mgr->idx = open ((char*)name, O_RDWR | O_CREAT, 0666); + + if( mgr->idx == -1 ) { + fprintf (stderr, "Unable to open btree file\n"); + return free(mgr), NULL; + } +#else + mgr = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, sizeof(BtMgr)); + attr = FILE_ATTRIBUTE_NORMAL; + mgr->idx = CreateFile(name, GENERIC_READ| GENERIC_WRITE, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, attr, NULL); + + if( mgr->idx == INVALID_HANDLE_VALUE ) + return GlobalFree(mgr), NULL; +#endif + +#ifdef unix + pagezero = valloc (BT_maxpage); + *amt = 0; + + // read minimum page size to get root info + // to support raw disk partition files + // check if bits == 0 on the disk. + + if( size = lseek (mgr->idx, 0L, 2) ) + if( pread(mgr->idx, pagezero, BT_minpage, 0) == BT_minpage ) + if( pagezero->alloc->bits ) + bits = pagezero->alloc->bits; + else + initit = 1; + else + return free(mgr), free(pagezero), NULL; + else + initit = 1; +#else + pagezero = VirtualAlloc(NULL, BT_maxpage, MEM_COMMIT, PAGE_READWRITE); + size = GetFileSize(mgr->idx, amt); + + if( size || *amt ) { + if( !ReadFile(mgr->idx, (char *)pagezero, BT_minpage, amt, NULL) ) + return bt_mgrclose (mgr), NULL; + bits = pagezero->alloc->bits; + } else + initit = 1; +#endif + + mgr->page_size = 1 << bits; + mgr->page_bits = bits; + + // calculate number of latch hash table entries + + mgr->nlatchpage = (nodemax/16 * sizeof(BtHashEntry) + mgr->page_size - 1) / mgr->page_size; + mgr->latchhash = ((uid)mgr->nlatchpage << mgr->page_bits) / sizeof(BtHashEntry); + + // add on the number of pages in buffer pool + // along with the corresponding latch table + + mgr->nlatchpage += nodemax; // size of the buffer pool in pages + mgr->nlatchpage += (sizeof(BtLatchSet) * nodemax + mgr->page_size - 1)/mgr->page_size; + mgr->latchtotal = nodemax; + + // add on the sizeof the lock manager hash table and the lock table + + mgr->nlatchpage += (lockmax / 16 * sizeof(BtHashEntry) + mgr->page_size - 1) / mgr->page_size; + + mgr->nlatchpage += (lockmax * sizeof(BtLockSet) + mgr->page_size - 1) / mgr->page_size; + + if( !initit ) + goto mgrlatch; + + // initialize an empty b-tree with latch page, root page, page of leaves + // and page(s) of latches and page pool cache + + memset (pagezero, 0, 1 << bits); + pagezero->alloc->bits = mgr->page_bits; + bt_putid(pagezero->alloc->right, MIN_lvl+1); + + // initialize left-most LEAF page in + // alloc->left. + + bt_putid (pagezero->alloc->left, LEAF_page); + + if( bt_writepage (mgr, pagezero->alloc, 0) ) { + fprintf (stderr, "Unable to create btree page zero\n"); + return bt_mgrclose (mgr), NULL; + } + + memset (pagezero, 0, 1 << bits); + pagezero->alloc->bits = mgr->page_bits; + + for( lvl=MIN_lvl; lvl--; ) { + slotptr(pagezero->alloc, 1)->off = mgr->page_size - 3 - (lvl ? BtId + sizeof(BtVal): sizeof(BtVal)); + key = keyptr(pagezero->alloc, 1); + key->len = 2; // create stopper key + key->key[0] = 0xff; + key->key[1] = 0xff; + + bt_putid(value, MIN_lvl - lvl + 1); + val = valptr(pagezero->alloc, 1); + val->len = lvl ? BtId : 0; + memcpy (val->value, value, val->len); + + pagezero->alloc->min = slotptr(pagezero->alloc, 1)->off; + pagezero->alloc->lvl = lvl; + pagezero->alloc->cnt = 1; + pagezero->alloc->act = 1; + + if( bt_writepage (mgr, pagezero->alloc, MIN_lvl - lvl) ) { + fprintf (stderr, "Unable to create btree page zero\n"); + return bt_mgrclose (mgr), NULL; + } + } + +mgrlatch: +#ifdef unix + free (pagezero); +#else + VirtualFree (pagezero, 0, MEM_RELEASE); +#endif +#ifdef unix + // mlock the pagezero page + + flag = PROT_READ | PROT_WRITE; + mgr->pagezero = mmap (0, mgr->page_size, flag, MAP_SHARED, mgr->idx, ALLOC_page << mgr->page_bits); + if( mgr->pagezero == MAP_FAILED ) { + fprintf (stderr, "Unable to mmap btree page zero, error = %d\n", errno); + return bt_mgrclose (mgr), NULL; + } + mlock (mgr->pagezero, mgr->page_size); + + mgr->hashtable = (void *)mmap (0, (uid)mgr->nlatchpage << mgr->page_bits, flag, MAP_ANONYMOUS | MAP_SHARED, -1, 0); + if( mgr->hashtable == MAP_FAILED ) { + fprintf (stderr, "Unable to mmap anonymous buffer pool pages, error = %d\n", errno); + return bt_mgrclose (mgr), NULL; + } +#else + flag = PAGE_READWRITE; + mgr->halloc = CreateFileMapping(mgr->idx, NULL, flag, 0, mgr->page_size, NULL); + if( !mgr->halloc ) { + fprintf (stderr, "Unable to create page zero memory mapping, error = %d\n", GetLastError()); + return bt_mgrclose (mgr), NULL; + } + + flag = FILE_MAP_WRITE; + mgr->pagezero = MapViewOfFile(mgr->halloc, flag, 0, 0, mgr->page_size); + if( !mgr->pagezero ) { + fprintf (stderr, "Unable to map page zero, error = %d\n", GetLastError()); + return bt_mgrclose (mgr), NULL; + } + + flag = PAGE_READWRITE; + size = (uid)mgr->nlatchpage << mgr->page_bits; + mgr->hpool = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, flag, size >> 32, size, NULL); + if( !mgr->hpool ) { + fprintf (stderr, "Unable to create buffer pool memory mapping, error = %d\n", GetLastError()); + return bt_mgrclose (mgr), NULL; + } + + flag = FILE_MAP_WRITE; + mgr->hashtable = MapViewOfFile(mgr->pool, flag, 0, 0, size); + if( !mgr->hashtable ) { + fprintf (stderr, "Unable to map buffer pool, error = %d\n", GetLastError()); + return bt_mgrclose (mgr), NULL; + } +#endif + + size = (mgr->latchhash * sizeof(BtHashEntry) + mgr->page_size - 1) / mgr->page_size; + mgr->latchsets = (BtLatchSet *)((unsigned char *)mgr->hashtable + size * mgr->page_size); + size = (sizeof(BtLatchSet) * nodemax + mgr->page_size - 1)/mgr->page_size; + + mgr->pagepool = (unsigned char *)mgr->hashtable + (size << mgr->page_bits); + mgr->hashlock = (BtHashEntry *)(mgr->pagepool + ((uid)nodemax << mgr->page_bits)); + mgr->locktable = (BtLockSet *)((unsigned char *)mgr->hashtable + ((uid)mgr->nlatchpage << mgr->page_bits) - lockmax * sizeof(BtLockSet)); + + mgr->lockfree = lockmax - 1; + mgr->lockhash = ((unsigned char *)mgr->locktable - (unsigned char *)mgr->hashlock) / sizeof(BtHashEntry); + + for( idx = 1; idx < lockmax; idx++ ) + mgr->locktable[idx].next = idx - 1; + + return mgr; +} + +// open BTree access method +// based on buffer manager + +BtDb *bt_open (BtMgr *mgr) +{ +BtDb *bt = malloc (sizeof(*bt)); + + memset (bt, 0, sizeof(*bt)); + bt->mgr = mgr; +#ifdef unix + bt->mem = valloc (2 *mgr->page_size); +#else + bt->mem = VirtualAlloc(NULL, 2 * mgr->page_size, MEM_COMMIT, PAGE_READWRITE); +#endif + bt->frame = (BtPage)bt->mem; + bt->cursor = (BtPage)(bt->mem + 1 * mgr->page_size); + return bt; +} + +// compare two keys, returning > 0, = 0, or < 0 +// as the comparison value + +int keycmp (BtKey* key1, unsigned char *key2, uint len2) +{ +uint len1 = key1->len; +int ans; + + if( ans = memcmp (key1->key, key2, len1 > len2 ? len2 : len1) ) + return ans; + + if( len1 > len2 ) + return 1; + if( len1 < len2 ) + return -1; + + return 0; +} + +// place write, read, or parent lock on requested page_no. + +void bt_lockpage(BtLock mode, BtLatchSet *set) +{ + switch( mode ) { + case BtLockRead: + ReadLock (set->readwr); + break; + case BtLockWrite: + WriteLock (set->readwr); + break; + case BtLockAccess: + ReadLock (set->access); + break; + case BtLockDelete: + WriteLock (set->access); + break; + case BtLockParent: + WriteLock (set->parent); + break; + } +} + +// remove write, read, or parent lock on requested page + +void bt_unlockpage(BtLock mode, BtLatchSet *set) +{ + switch( mode ) { + case BtLockRead: + ReadRelease (set->readwr); + break; + case BtLockWrite: + WriteRelease (set->readwr); + break; + case BtLockAccess: + ReadRelease (set->access); + break; + case BtLockDelete: + WriteRelease (set->access); + break; + case BtLockParent: + WriteRelease (set->parent); + break; + } +} + +// allocate a new page +// return with page latched. + +int bt_newpage(BtDb *bt, BtPageSet *set, BtPage contents) +{ +int blk; + + // lock allocation page + + bt_spinwritelock(bt->mgr->alloclatch); + + // use empty chain first + // else allocate empty page + + if( set->page_no = bt_getid(bt->mgr->pagezero->chain) ) { + if( set->latch = bt_pinlatch (bt, set->page_no, 1) ) + set->page = bt_mappage (bt, set->latch); + else + return bt->err = BTERR_struct, -1; + + bt_putid(bt->mgr->pagezero->chain, bt_getid(set->page->right)); + bt_spinreleasewrite(bt->mgr->alloclatch); + + memcpy (set->page, contents, bt->mgr->page_size); + set->latch->dirty = 1; + return 0; + } + + set->page_no = bt_getid(bt->mgr->pagezero->alloc->right); + bt_putid(bt->mgr->pagezero->alloc->right, set->page_no+1); + + // unlock allocation latch + + bt_spinreleasewrite(bt->mgr->alloclatch); + + // don't load cache from btree page + + if( set->latch = bt_pinlatch (bt, set->page_no, 0) ) + set->page = bt_mappage (bt, set->latch); + else + return bt->err = BTERR_struct; + + memcpy (set->page, contents, bt->mgr->page_size); + set->latch->dirty = 1; + return 0; +} + +// find slot in page for given key at a given level + +int bt_findslot (BtPageSet *set, unsigned char *key, uint len) +{ +uint diff, higher = set->page->cnt, low = 1, slot; +uint good = 0; + + // make stopper key an infinite fence value + + if( bt_getid (set->page->right) ) + higher++; + else + good++; + + // low is the lowest candidate. + // loop ends when they meet + + // higher is already + // tested as .ge. the passed key. + + while( diff = higher - low ) { + slot = low + ( diff >> 1 ); + if( keycmp (keyptr(set->page, slot), key, len) < 0 ) + low = slot + 1; + else + higher = slot, good++; + } + + // return zero if key is on right link page + + return good ? higher : 0; +} + +// find and load page at given level for given key +// leave page rd or wr locked as requested + +int bt_loadpage (BtDb *bt, BtPageSet *set, unsigned char *key, uint len, uint lvl, BtLock lock) +{ +uid page_no = ROOT_page, prevpage = 0; +uint drill = 0xff, slot; +BtLatchSet *prevlatch; +uint mode, prevmode; + + // start at root of btree and drill down + + do { + // determine lock mode of drill level + mode = (drill == lvl) ? lock : BtLockRead; + + if( set->latch = bt_pinlatch (bt, page_no, 1) ) + set->page_no = page_no; + else + return 0; + + // obtain access lock using lock chaining with Access mode + + if( page_no > ROOT_page ) + bt_lockpage(BtLockAccess, set->latch); + + set->page = bt_mappage (bt, set->latch); + + // release & unpin parent page + + if( prevpage ) { + bt_unlockpage(prevmode, prevlatch); + bt_unpinlatch (prevlatch); + prevpage = 0; + } + + // obtain read lock using lock chaining + + bt_lockpage(mode, set->latch); + + if( set->page->free ) + return bt->err = BTERR_struct, 0; + + if( page_no > ROOT_page ) + bt_unlockpage(BtLockAccess, set->latch); + + // re-read and re-lock root after determining actual level of root + + if( set->page->lvl != drill) { + if( set->page_no != ROOT_page ) + return bt->err = BTERR_struct, 0; + + drill = set->page->lvl; + + if( lock != BtLockRead && drill == lvl ) { + bt_unlockpage(mode, set->latch); + bt_unpinlatch (set->latch); + continue; + } + } + + prevpage = set->page_no; + prevlatch = set->latch; + prevmode = mode; + + // find key on page at this level + // and descend to requested level + + if( set->page->kill ) + goto slideright; + + if( slot = bt_findslot (set, key, len) ) { + if( drill == lvl ) + return slot; + + while( slotptr(set->page, slot)->dead ) + if( slot++ < set->page->cnt ) + continue; + else + goto slideright; + + page_no = bt_getid(valptr(set->page, slot)->value); + drill--; + continue; + } + + // or slide right into next page + +slideright: + page_no = bt_getid(set->page->right); + + } while( page_no ); + + // return error on end of right chain + + bt->err = BTERR_struct; + return 0; // return error +} + +// return page to free list +// page must be delete & write locked + +void bt_freepage (BtDb *bt, BtPageSet *set) +{ + // lock allocation page + + bt_spinwritelock (bt->mgr->alloclatch); + + // store chain + memcpy(set->page->right, bt->mgr->pagezero->chain, BtId); + bt_putid(bt->mgr->pagezero->chain, set->page_no); + set->latch->dirty = 1; + set->page->free = 1; + + // unlock released page + + bt_unlockpage (BtLockDelete, set->latch); + bt_unlockpage (BtLockWrite, set->latch); + bt_unpinlatch (set->latch); + + // unlock allocation page + + bt_spinreleasewrite (bt->mgr->alloclatch); +} + +// a fence key was deleted from a page +// push new fence value upwards + +BTERR bt_fixfence (BtDb *bt, BtPageSet *set, uint lvl) +{ +unsigned char leftkey[BT_keyarray], rightkey[BT_keyarray]; +unsigned char value[BtId]; +BtKey* ptr; +uint idx; + + // remove the old fence value + + ptr = keyptr(set->page, set->page->cnt); + memcpy (rightkey, ptr, ptr->len + sizeof(BtKey)); + memset (slotptr(set->page, set->page->cnt--), 0, sizeof(BtSlot)); + set->latch->dirty = 1; + + // cache new fence value + + ptr = keyptr(set->page, set->page->cnt); + memcpy (leftkey, ptr, ptr->len + sizeof(BtKey)); + + bt_lockpage (BtLockParent, set->latch); + bt_unlockpage (BtLockWrite, set->latch); + + // insert new (now smaller) fence key + + bt_putid (value, set->page_no); + ptr = (BtKey*)leftkey; + + if( bt_insertkey (bt, ptr->key, ptr->len, lvl+1, value, BtId, 1) ) + return bt->err; + + // now delete old fence key + + ptr = (BtKey*)rightkey; + + if( bt_deletekey (bt, ptr->key, ptr->len, lvl+1) ) + return bt->err; + + bt_unlockpage (BtLockParent, set->latch); + bt_unpinlatch(set->latch); + return 0; +} + +// root has a single child +// collapse a level from the tree + +BTERR bt_collapseroot (BtDb *bt, BtPageSet *root) +{ +BtPageSet child[1]; +uint idx; + + // find the child entry and promote as new root contents + + do { + for( idx = 0; idx++ < root->page->cnt; ) + if( !slotptr(root->page, idx)->dead ) + break; + + child->page_no = bt_getid (valptr(root->page, idx)->value); + + if( child->latch = bt_pinlatch (bt, child->page_no, 1) ) + child->page = bt_mappage (bt, child->latch); + else + return bt->err; + + bt_lockpage (BtLockDelete, child->latch); + bt_lockpage (BtLockWrite, child->latch); + + memcpy (root->page, child->page, bt->mgr->page_size); + root->latch->dirty = 1; + + bt_freepage (bt, child); + + } while( root->page->lvl > 1 && root->page->act == 1 ); + + bt_unlockpage (BtLockWrite, root->latch); + bt_unpinlatch (root->latch); + return 0; +} + +// maintain reverse scan pointers by +// linking left pointer of far right node + +BTERR bt_linkleft (BtDb *bt, uid left_page_no, uid right_page_no) +{ +BtPageSet right2[1]; + + // keep track of rightmost leaf page + + if( !right_page_no ) { + bt_putid (bt->mgr->pagezero->alloc->left, left_page_no); + return 0; + } + + // link right page to left page + + if( right2->latch = bt_pinlatch (bt, right_page_no, 1) ) + right2->page = bt_mappage (bt, right2->latch); + else + return bt->err; + + bt_lockpage (BtLockWrite, right2->latch); + + bt_putid(right2->page->left, left_page_no); + bt_unlockpage (BtLockWrite, right2->latch); + bt_unpinlatch (right2->latch); + return 0; +} + +// find and delete key on page by marking delete flag bit +// if page becomes empty, delete it from the btree + +BTERR bt_deletekey (BtDb *bt, unsigned char *key, uint len, uint lvl) +{ +unsigned char lowerfence[BT_keyarray], higherfence[BT_keyarray]; +uint slot, idx, found, fence; +BtPageSet set[1], right[1]; +unsigned char value[BtId]; +BtKey *ptr, *tst; +BtVal *val; + + if( slot = bt_loadpage (bt, set, key, len, lvl, BtLockWrite) ) + ptr = keyptr(set->page, slot); + else + return bt->err; + + // if librarian slot, advance to real slot + + if( slotptr(set->page, slot)->type == Librarian ) + ptr = keyptr(set->page, ++slot); + + fence = slot == set->page->cnt; + + // if key is found delete it, otherwise ignore request + + if( found = !keycmp (ptr, key, len) ) + if( found = slotptr(set->page, slot)->dead == 0 ) { + val = valptr(set->page,slot); + slotptr(set->page, slot)->dead = 1; + set->page->garbage += ptr->len + val->len + sizeof(BtKey) + sizeof(BtVal); + set->page->act--; + + // collapse empty slots beneath the fence + + while( idx = set->page->cnt - 1 ) + if( slotptr(set->page, idx)->dead ) { + *slotptr(set->page, idx) = *slotptr(set->page, idx + 1); + memset (slotptr(set->page, set->page->cnt--), 0, sizeof(BtSlot)); + } else + break; + } + + // did we delete a fence key in an upper level? + + if( found && lvl && set->page->act && fence ) + if( bt_fixfence (bt, set, lvl) ) + return bt->err; + else + return bt->found = found, 0; + + // do we need to collapse root? + + if( lvl > 1 && set->page_no == ROOT_page && set->page->act == 1 ) + if( bt_collapseroot (bt, set) ) + return bt->err; + else + return bt->found = found, 0; + + // return if page is not empty + + if( set->page->act ) { + set->latch->dirty = 1; + bt_unlockpage(BtLockWrite, set->latch); + bt_unpinlatch (set->latch); + return bt->found = found, 0; + } + + // cache copy of fence key + // to post in parent + + ptr = keyptr(set->page, set->page->cnt); + memcpy (lowerfence, ptr, ptr->len + sizeof(BtKey)); + + // obtain lock on right page + + right->page_no = bt_getid(set->page->right); + + if( right->latch = bt_pinlatch (bt, right->page_no, 1) ) + right->page = bt_mappage (bt, right->latch); + else + return 0; + + bt_lockpage (BtLockWrite, right->latch); + + if( right->page->kill ) + return bt->err = BTERR_struct; + + // transfer left link + + memcpy (right->page->left, set->page->left, BtId); + + // pull contents of right peer into our empty page + + memcpy (set->page, right->page, bt->mgr->page_size); + set->latch->dirty = 1; + + // update left link + + if( !lvl ) + if( bt_linkleft (bt, set->page_no, bt_getid (set->page->right)) ) + return bt->err; + + // cache copy of key to update + + ptr = keyptr(right->page, right->page->cnt); + memcpy (higherfence, ptr, ptr->len + sizeof(BtKey)); + + // mark right page deleted and point it to left page + // until we can post parent updates + + bt_putid (right->page->right, set->page_no); + right->latch->dirty = 1; + right->page->kill = 1; + + bt_lockpage (BtLockParent, right->latch); + bt_unlockpage (BtLockWrite, right->latch); + + bt_lockpage (BtLockParent, set->latch); + bt_unlockpage (BtLockWrite, set->latch); + + // redirect higher key directly to our new node contents + + bt_putid (value, set->page_no); + ptr = (BtKey*)higherfence; + + if( bt_insertkey (bt, ptr->key, ptr->len, lvl+1, value, BtId, 1) ) + return bt->err; + + // delete old lower key to our node + + ptr = (BtKey*)lowerfence; + + if( bt_deletekey (bt, ptr->key, ptr->len, lvl+1) ) + return bt->err; + + // obtain delete and write locks to right node + + bt_unlockpage (BtLockParent, right->latch); + bt_lockpage (BtLockDelete, right->latch); + bt_lockpage (BtLockWrite, right->latch); + bt_freepage (bt, right); + + bt_unlockpage (BtLockParent, set->latch); + bt_unpinlatch (set->latch); + bt->found = found; + return 0; +} + +BtKey *bt_foundkey (BtDb *bt) +{ + return (BtKey*)(bt->key); +} + +// advance to next slot + +uint bt_findnext (BtDb *bt, BtPageSet *set, uint slot) +{ +BtLatchSet *prevlatch; +uid page_no; + + if( slot < set->page->cnt ) + return slot + 1; + + prevlatch = set->latch; + + if( page_no = bt_getid(set->page->right) ) + if( set->latch = bt_pinlatch (bt, page_no, 1) ) + set->page = bt_mappage (bt, set->latch); + else + return 0; + else + return bt->err = BTERR_struct, 0; + + // obtain access lock using lock chaining with Access mode + + bt_lockpage(BtLockAccess, set->latch); + + bt_unlockpage(BtLockRead, prevlatch); + bt_unpinlatch (prevlatch); + + bt_lockpage(BtLockRead, set->latch); + bt_unlockpage(BtLockAccess, set->latch); + + set->page_no = page_no; + return 1; +} + +// find unique key or first duplicate key in +// leaf level and return number of value bytes +// or (-1) if not found. Setup key for bt_foundkey + +int bt_findkey (BtDb *bt, unsigned char *key, uint keylen, unsigned char *value, uint valmax) +{ +BtPageSet set[1]; +uint len, slot; +int ret = -1; +BtKey *ptr; +BtVal *val; + + if( slot = bt_loadpage (bt, set, key, keylen, 0, BtLockRead) ) + do { + ptr = keyptr(set->page, slot); + + // skip librarian slot place holder + + if( slotptr(set->page, slot)->type == Librarian ) + ptr = keyptr(set->page, ++slot); + + // return actual key found + + memcpy (bt->key, ptr, ptr->len + sizeof(BtKey)); + len = ptr->len; + + if( slotptr(set->page, slot)->type == Duplicate ) + len -= BtId; + + // not there if we reach the stopper key + + if( slot == set->page->cnt ) + if( !bt_getid (set->page->right) ) + break; + + // if key exists, return >= 0 value bytes copied + // otherwise return (-1) + + if( slotptr(set->page, slot)->dead ) + continue; + + if( keylen == len ) + if( !memcmp (ptr->key, key, len) ) { + val = valptr (set->page,slot); + if( valmax > val->len ) + valmax = val->len; + memcpy (value, val->value, valmax); + ret = valmax; + } + + break; + + } while( slot = bt_findnext (bt, set, slot) ); + + bt_unlockpage (BtLockRead, set->latch); + bt_unpinlatch (set->latch); + return ret; +} + +// check page for space available, +// clean if necessary and return +// 0 - page needs splitting +// >0 new slot value + +uint bt_cleanpage(BtDb *bt, BtPageSet *set, uint keylen, uint slot, uint vallen) +{ +uint nxt = bt->mgr->page_size; +BtPage page = set->page; +uint cnt = 0, idx = 0; +uint max = page->cnt; +uint newslot = max; +BtKey *key; +BtVal *val; + + if( page->min >= (max+2) * sizeof(BtSlot) + sizeof(*page) + keylen + sizeof(BtKey) + vallen + sizeof(BtVal)) + return slot; + + // skip cleanup and proceed to split + // if there's not enough garbage + // to bother with. + + if( page->garbage < nxt / 5 ) + return 0; + + memcpy (bt->frame, page, bt->mgr->page_size); + + // skip page info and set rest of page to zero + + memset (page+1, 0, bt->mgr->page_size - sizeof(*page)); + set->latch->dirty = 1; + page->garbage = 0; + page->act = 0; + + // clean up page first by + // removing deleted keys + + while( cnt++ < max ) { + if( cnt == slot ) + newslot = idx + 2; + if( cnt < max && slotptr(bt->frame,cnt)->dead ) + continue; + + // copy the value across + + val = valptr(bt->frame, cnt); + nxt -= val->len + sizeof(BtVal); + memcpy ((unsigned char *)page + nxt, val, val->len + sizeof(BtVal)); + + // copy the key across + + key = keyptr(bt->frame, cnt); + nxt -= key->len + sizeof(BtKey); + memcpy ((unsigned char *)page + nxt, key, key->len + sizeof(BtKey)); + + // make a librarian slot + + if( idx ) { + slotptr(page, ++idx)->off = nxt; + slotptr(page, idx)->type = Librarian; + slotptr(page, idx)->dead = 1; + } + + // set up the slot + + slotptr(page, ++idx)->off = nxt; + slotptr(page, idx)->type = slotptr(bt->frame, cnt)->type; + + if( !(slotptr(page, idx)->dead = slotptr(bt->frame, cnt)->dead) ) + page->act++; + } + + page->min = nxt; + page->cnt = idx; + + // see if page has enough space now, or does it need splitting? + + if( page->min >= (idx+2) * sizeof(BtSlot) + sizeof(*page) + keylen + sizeof(BtKey) + vallen + sizeof(BtVal) ) + return newslot; + + return 0; +} + +// split the root and raise the height of the btree + +BTERR bt_splitroot(BtDb *bt, BtPageSet *root, BtKey *leftkey, BtPageSet *right) +{ +uint nxt = bt->mgr->page_size; +unsigned char value[BtId]; +BtPageSet left[1]; +BtKey *ptr; +BtVal *val; + + // Obtain an empty page to use, and copy the current + // root contents into it, e.g. lower keys + + if( bt_newpage(bt, left, root->page) ) + return bt->err; + + bt_unpinlatch (left->latch); + + // set left from higher to lower page + + bt_putid (right->page->left, left->page_no); + bt_unpinlatch (right->latch); + + // preserve the page info at the bottom + // of higher keys and set rest to zero + + memset(root->page+1, 0, bt->mgr->page_size - sizeof(*root->page)); + + // insert stopper key at top of newroot page + // and increase the root height + + nxt -= BtId + sizeof(BtVal); + bt_putid (value, right->page_no); + val = (BtVal *)((unsigned char *)root->page + nxt); + memcpy (val->value, value, BtId); + val->len = BtId; + + nxt -= 2 + sizeof(BtKey); + slotptr(root->page, 2)->off = nxt; + ptr = (BtKey *)((unsigned char *)root->page + nxt); + ptr->len = 2; + ptr->key[0] = 0xff; + ptr->key[1] = 0xff; + + // insert lower keys page fence key on newroot page as first key + + nxt -= BtId + sizeof(BtVal); + bt_putid (value, left->page_no); + val = (BtVal *)((unsigned char *)root->page + nxt); + memcpy (val->value, value, BtId); + val->len = BtId; + + nxt -= leftkey->len + sizeof(BtKey); + slotptr(root->page, 1)->off = nxt; + memcpy ((unsigned char *)root->page + nxt, leftkey, leftkey->len + sizeof(BtKey)); + + bt_putid(root->page->right, 0); + root->page->min = nxt; // reset lowest used offset and key count + root->page->cnt = 2; + root->page->act = 2; + root->page->lvl++; + + // release and unpin root pages + + bt_unlockpage(BtLockWrite, root->latch); + bt_unpinlatch (root->latch); + return 0; +} + +// split already locked full node +// return unlocked. + +BTERR bt_splitpage (BtDb *bt, BtPageSet *set) +{ +unsigned char fencekey[BT_keyarray], rightkey[BT_keyarray]; +uint cnt = 0, idx = 0, max, nxt = bt->mgr->page_size; +unsigned char value[BtId]; +uint lvl = set->page->lvl; +BtPageSet right[1]; +BtKey *key, *ptr; +BtVal *val, *src; +uid right2; +uint prev; + + // split higher half of keys to bt->frame + + memset (bt->frame, 0, bt->mgr->page_size); + max = set->page->cnt; + cnt = max / 2; + idx = 0; + + while( cnt++ < max ) { + if( slotptr(set->page, cnt)->dead && cnt < max ) + continue; + src = valptr(set->page, cnt); + nxt -= src->len + sizeof(BtVal); + memcpy ((unsigned char *)bt->frame + nxt, src, src->len + sizeof(BtVal)); + + key = keyptr(set->page, cnt); + nxt -= key->len + sizeof(BtKey); + ptr = (BtKey*)((unsigned char *)bt->frame + nxt); + memcpy (ptr, key, key->len + sizeof(BtKey)); + + // add librarian slot + + if( idx ) { + slotptr(bt->frame, ++idx)->off = nxt; + slotptr(bt->frame, idx)->type = Librarian; + slotptr(bt->frame, idx)->dead = 1; + } + + // add actual slot + + slotptr(bt->frame, ++idx)->off = nxt; + slotptr(bt->frame, idx)->type = slotptr(set->page, cnt)->type; + + if( !(slotptr(bt->frame, idx)->dead = slotptr(set->page, cnt)->dead) ) + bt->frame->act++; + } + + // remember existing fence key for new page to the right + + memcpy (rightkey, key, key->len + sizeof(BtKey)); + + bt->frame->bits = bt->mgr->page_bits; + bt->frame->min = nxt; + bt->frame->cnt = idx; + bt->frame->lvl = lvl; + + // link right node + + if( set->page_no > ROOT_page ) { + bt_putid (bt->frame->right, bt_getid (set->page->right)); + bt_putid(bt->frame->left, set->page_no); + } + + // get new free page and write higher keys to it. + + if( bt_newpage(bt, right, bt->frame) ) + return bt->err; + + // link left node + + if( set->page_no > ROOT_page && !lvl ) + if( bt_linkleft (bt, right->page_no, bt_getid (set->page->right)) ) + return bt->err; + + // update lower keys to continue in old page + + memcpy (bt->frame, set->page, bt->mgr->page_size); + memset (set->page+1, 0, bt->mgr->page_size - sizeof(*set->page)); + set->latch->dirty = 1; + + nxt = bt->mgr->page_size; + set->page->garbage = 0; + set->page->act = 0; + max /= 2; + cnt = 0; + idx = 0; + + if( slotptr(bt->frame, max)->type == Librarian ) + max--; + + // assemble page of smaller keys + + while( cnt++ < max ) { + if( slotptr(bt->frame, cnt)->dead ) + continue; + val = valptr(bt->frame, cnt); + nxt -= val->len + sizeof(BtVal); + memcpy ((unsigned char *)set->page + nxt, val, val->len + sizeof(BtVal)); + + key = keyptr(bt->frame, cnt); + nxt -= key->len + sizeof(BtKey); + memcpy ((unsigned char *)set->page + nxt, key, key->len + sizeof(BtKey)); + + // add librarian slot + + if( idx ) { + slotptr(set->page, ++idx)->off = nxt; + slotptr(set->page, idx)->type = Librarian; + slotptr(set->page, idx)->dead = 1; + } + + // add actual slot + + slotptr(set->page, ++idx)->off = nxt; + slotptr(set->page, idx)->type = slotptr(bt->frame, cnt)->type; + set->page->act++; + } + + // remember fence key for smaller page + + memcpy(fencekey, key, key->len + sizeof(BtKey)); + + bt_putid(set->page->right, right->page_no); + set->page->min = nxt; + set->page->cnt = idx; + + // if current page is the root page, split it + + if( set->page_no == ROOT_page ) + return bt_splitroot (bt, set, (BtKey *)fencekey, right); + + // insert new fences in their parent pages + + bt_lockpage (BtLockParent, right->latch); + + bt_lockpage (BtLockParent, set->latch); + bt_unlockpage (BtLockWrite, set->latch); + + // insert new fence for reformulated left block of smaller keys + + bt_putid (value, set->page_no); + + if( bt_insertkey (bt, fencekey+1, *fencekey, lvl+1, value, BtId, 1) ) + return bt->err; + + // switch fence for right block of larger keys to new right page + + bt_putid (value, right->page_no); + + if( bt_insertkey (bt, rightkey+1, *rightkey, lvl+1, value, BtId, 1) ) + return bt->err; + + bt_unlockpage (BtLockParent, set->latch); + bt_unpinlatch (set->latch); + + bt_unlockpage (BtLockParent, right->latch); + bt_unpinlatch (right->latch); + return 0; +} + +// install new key and value onto page +// page must already be checked for +// adequate space + +BTERR bt_insertslot (BtDb *bt, BtPageSet *set, uint slot, unsigned char *key,uint keylen, unsigned char *value, uint vallen, uint type) +{ +uint idx, librarian; +BtSlot *node; +BtKey *ptr; +BtVal *val; + + // if found slot > desired slot and previous slot + // is a librarian slot, use it + + if( slot > 1 ) + if( slotptr(set->page, slot-1)->type == Librarian ) + slot--; + + // copy value onto page + + set->page->min -= vallen + sizeof(BtVal); + val = (BtVal*)((unsigned char *)set->page + set->page->min); + memcpy (val->value, value, vallen); + val->len = vallen; + + // copy key onto page + + set->page->min -= keylen + sizeof(BtKey); + ptr = (BtKey*)((unsigned char *)set->page + set->page->min); + memcpy (ptr->key, key, keylen); + ptr->len = keylen; + + // find first empty slot + + for( idx = slot; idx < set->page->cnt; idx++ ) + if( slotptr(set->page, idx)->dead ) + break; + + // now insert key into array before slot + + if( idx == set->page->cnt ) + idx += 2, set->page->cnt += 2, librarian = 2; + else + librarian = 1; + + set->latch->dirty = 1; + set->page->act++; + + while( idx > slot + librarian - 1 ) + *slotptr(set->page, idx) = *slotptr(set->page, idx - librarian), idx--; + + // add librarian slot + + if( librarian > 1 ) { + node = slotptr(set->page, slot++); + node->off = set->page->min; + node->type = Librarian; + node->dead = 1; + } + + // fill in new slot + + node = slotptr(set->page, slot); + node->off = set->page->min; + node->type = type; + node->dead = 0; + + bt_unlockpage (BtLockWrite, set->latch); + bt_unpinlatch (set->latch); + return 0; +} + +// Insert new key into the btree at given level. +// either add a new key or update/add an existing one + +BTERR bt_insertkey (BtDb *bt, unsigned char *key, uint keylen, uint lvl, void *value, uint vallen, int unique) +{ +unsigned char newkey[BT_keyarray]; +uint slot, idx, len; +BtPageSet set[1]; +BtKey *ptr, *ins; +uid sequence; +BtVal *val; +uint type; + + // set up the key we're working on + + ins = (BtKey*)newkey; + memcpy (ins->key, key, keylen); + ins->len = keylen; + + // is this a non-unique index value? + + if( unique ) + type = Unique; + else { + type = Duplicate; + sequence = bt_newdup (bt); + bt_putid (ins->key + ins->len + sizeof(BtKey), sequence); + ins->len += BtId; + } + + while( 1 ) { // find the page and slot for the current key + if( slot = bt_loadpage (bt, set, ins->key, ins->len, lvl, BtLockWrite) ) + ptr = keyptr(set->page, slot); + else { + if( !bt->err ) + bt->err = BTERR_ovflw; + return bt->err; + } + + // if librarian slot == found slot, advance to real slot + + if( slotptr(set->page, slot)->type == Librarian ) + if( !keycmp (ptr, key, keylen) ) + ptr = keyptr(set->page, ++slot); + + len = ptr->len; + + if( slotptr(set->page, slot)->type == Duplicate ) + len -= BtId; + + // if inserting a duplicate key or unique key + // check for adequate space on the page + // and insert the new key before slot. + + if( unique && (len != ins->len || memcmp (ptr->key, ins->key, ins->len)) || !unique ) { + if( !(slot = bt_cleanpage (bt, set, ins->len, slot, vallen)) ) + if( bt_splitpage (bt, set) ) + return bt->err; + else + continue; + + return bt_insertslot (bt, set, slot, ins->key, ins->len, value, vallen, type); + } + + // if key already exists, update value and return + + val = valptr(set->page, slot); + + if( val->len >= vallen ) { + if( slotptr(set->page, slot)->dead ) + set->page->act++; + set->page->garbage += val->len - vallen; + set->latch->dirty = 1; + slotptr(set->page, slot)->dead = 0; + val->len = vallen; + memcpy (val->value, value, vallen); + bt_unlockpage(BtLockWrite, set->latch); + bt_unpinlatch (set->latch); + return 0; + } + + // new update value doesn't fit in existing value area + + if( !slotptr(set->page, slot)->dead ) + set->page->garbage += val->len + ptr->len + sizeof(BtKey) + sizeof(BtVal); + else { + slotptr(set->page, slot)->dead = 0; + set->page->act++; + } + + if( !(slot = bt_cleanpage (bt, set, keylen, slot, vallen)) ) + if( bt_splitpage (bt, set) ) + return bt->err; + else + continue; + + set->page->min -= vallen + sizeof(BtVal); + val = (BtVal*)((unsigned char *)set->page + set->page->min); + memcpy (val->value, value, vallen); + val->len = vallen; + + set->latch->dirty = 1; + set->page->min -= keylen + sizeof(BtKey); + ptr = (BtKey*)((unsigned char *)set->page + set->page->min); + memcpy (ptr->key, key, keylen); + ptr->len = keylen; + + slotptr(set->page, slot)->off = set->page->min; + bt_unlockpage(BtLockWrite, set->latch); + bt_unpinlatch (set->latch); + return 0; + } + return 0; +} + +// compute hash of string + +uint bt_hashkey (unsigned char *key, unsigned int len) +{ +uint hash = 0; + + while( len >= sizeof(uint) ) + hash *= 11, hash += *(uint *)key, len -= sizeof(uint), key += sizeof(uint); + + while( len ) + hash *= 11, hash += *key++ * len--; + + return hash; +} + +// add a new lock table entry + +uint bt_newlock (BtDb *bt, BtKey *key, uint hashidx) +{ +BtLockSet *lock = bt->mgr->locktable; +uint slot, prev; + + // obtain lock manager global lock + + bt_spinwritelock (bt->mgr->locklatch); + + // return NULL if table is full + + if( !(slot = bt->mgr->lockfree) ) { + bt_spinreleasewrite (bt->mgr->locklatch); + return 0; + } + + // maintain free chain + + bt->mgr->lockfree = lock[slot].next; + bt_spinreleasewrite (bt->mgr->locklatch); + + if( prev = bt->mgr->hashlock[hashidx].slot ) + lock[prev].prev = slot; + + bt->mgr->hashlock[hashidx].slot = slot; + lock[slot].hashidx = hashidx; + lock[slot].next = prev; + lock[slot].prev = 0; + + // save the key being locked + + memcpy (lock[slot].key, key, key->len + sizeof(BtKey)); + return slot; +} + +// add key to the lock table +// block until available. + +uint bt_setlock(BtDb *bt, BtKey *key) +{ +uint hashidx = bt_hashkey(key->key, key->len) % bt->mgr->lockhash; +BtLockSet *lock = NULL; +BtKey *key2; +uint slot; + + // find existing lock entry + // or recover from full table + + while( lock == NULL ) { + // obtain lock on hash slot + + bt_spinwritelock (bt->mgr->hashlock[hashidx].latch); + + if( slot = bt->mgr->hashlock[hashidx].slot ) + do { + lock = bt->mgr->locktable + slot; + key2 = (BtKey *)lock->key; + + if( !keycmp (key, key2->key, key2->len) ) + break; + } while( slot = lock->next ); + + if( slot ) + break; + + if( slot = bt_newlock (bt, key, hashidx) ) + break; + + bt_spinreleasewrite (bt->mgr->hashlock[hashidx].latch); +#ifdef unix + sched_yield(); +#else + SwitchToThread (); +#endif + } + + lock = bt->mgr->locktable + slot; + lock->pin++; + + bt_spinreleasewrite (bt->mgr->hashlock[hashidx].latch); + WriteLock (lock->readwr); + return slot; +} + +void bt_lockclr (BtDb *bt, uint slot) +{ +BtLockSet *lock = bt->mgr->locktable + slot; +uint hashidx = lock->hashidx; +uint next, prev; + + bt_spinwritelock (bt->mgr->hashlock[hashidx].latch); + WriteRelease (lock->readwr); + + // if entry is no longer in use, + // return it to the free chain. + + if( !--lock->pin ) { + if( next = lock->next ) + bt->mgr->locktable[next].prev = lock->prev; + + if( prev = lock->prev ) + bt->mgr->locktable[prev].next = lock->next; + else + bt->mgr->hashlock[lock->hashidx].slot = next; + + bt_spinwritelock (bt->mgr->locklatch); + lock->next = bt->mgr->lockfree; + bt->mgr->lockfree = slot; + bt_spinreleasewrite (bt->mgr->locklatch); + } + + bt_spinreleasewrite (bt->mgr->hashlock[hashidx].latch); +} + +// atomic insert of a batch of keys. +// return -1 if BTERR is set +// otherwise return slot number +// causing the key constraint violation +// or zero on successful completion. + +int bt_atomicinsert (BtDb *bt, BtPage source) +{ +uint locks[MAX_atomic]; +BtKey *key, *key2; +int result = 0; +BtSlot temp[1]; +uint slot, idx; +BtVal *val; +int type; + + // first sort the list of keys into order to + // prevent deadlocks between threads. + + for( slot = 1; slot++ < source->cnt; ) { + *temp = *slotptr(source,slot); + key = keyptr (source,slot); + for( idx = slot; --idx; ) { + key2 = keyptr (source,idx); + if( keycmp (key, key2->key, key2->len) < 0 ) { + *slotptr(source,idx+1) = *slotptr(source,idx); + *slotptr(source,idx) = *temp; + } else + break; + } + } + + // take each unique-type key and add it to the lock table + + for( slot = 0; slot++ < source->cnt; ) + if( slotptr(source, slot)->type == Unique ) + locks[slot] = bt_setlock (bt, keyptr(source,slot)); + + // Lookup each unique key and determine constraint violations + + for( slot = 0; slot++ < source->cnt; ) + if( slotptr(source, slot)->type == Unique ) { + key = keyptr(source, slot); + if( bt_findkey (bt, key->key, key->len, NULL, 0) < 0 ) + continue; + result = slot; + break; + } + + // add each key to the btree + + if( !result ) + for( slot = 0; slot++ < source->cnt; ) { + key = keyptr(source,slot); + val = valptr(source,slot); + type = slotptr(source,slot)->type; + if( bt_insertkey (bt, key->key, key->len, 0, val->value, val->len, type == Unique) ) + return -1; + } + + // remove each unique-type key from the lock table + + for( slot = 0; slot++ < source->cnt; ) + if( slotptr(source, slot)->type == Unique ) + bt_lockclr (bt, locks[slot]); + + return result; +} + +// set cursor to highest slot on highest page + +uint bt_lastkey (BtDb *bt) +{ +uid page_no = bt_getid (bt->mgr->pagezero->alloc->left); +BtPageSet set[1]; +uint slot; + + if( set->latch = bt_pinlatch (bt, page_no, 1) ) + set->page = bt_mappage (bt, set->latch); + else + return 0; + + bt_lockpage(BtLockRead, set->latch); + + memcpy (bt->cursor, set->page, bt->mgr->page_size); + slot = set->page->cnt; + + bt_unlockpage(BtLockRead, set->latch); + bt_unpinlatch (set->latch); + return slot; +} + +// return previous slot on cursor page + +uint bt_prevkey (BtDb *bt, uint slot) +{ +BtPageSet set[1]; +uid left; + + if( --slot ) + return slot; + + if( left = bt_getid(bt->cursor->left) ) + bt->cursor_page = left; + else + return 0; + + if( set->latch = bt_pinlatch (bt, left, 1) ) + set->page = bt_mappage (bt, set->latch); + else + return 0; + + bt_lockpage(BtLockRead, set->latch); + memcpy (bt->cursor, set->page, bt->mgr->page_size); + bt_unlockpage(BtLockRead, set->latch); + bt_unpinlatch (set->latch); + return bt->cursor->cnt; +} + +// return next slot on cursor page +// or slide cursor right into next page + +uint bt_nextkey (BtDb *bt, uint slot) +{ +BtPageSet set[1]; +uid right; + + do { + right = bt_getid(bt->cursor->right); + + while( slot++ < bt->cursor->cnt ) + if( slotptr(bt->cursor,slot)->dead ) + continue; + else if( right || (slot < bt->cursor->cnt) ) // skip infinite stopper + return slot; + else + break; + + if( !right ) + break; + + bt->cursor_page = right; + + if( set->latch = bt_pinlatch (bt, right, 1) ) + set->page = bt_mappage (bt, set->latch); + else + return 0; + + bt_lockpage(BtLockRead, set->latch); + + memcpy (bt->cursor, set->page, bt->mgr->page_size); + + bt_unlockpage(BtLockRead, set->latch); + bt_unpinlatch (set->latch); + slot = 0; + + } while( 1 ); + + return bt->err = 0; +} + +// cache page of keys into cursor and return starting slot for given key + +uint bt_startkey (BtDb *bt, unsigned char *key, uint len) +{ +BtPageSet set[1]; +uint slot; + + // cache page for retrieval + + if( slot = bt_loadpage (bt, set, key, len, 0, BtLockRead) ) + memcpy (bt->cursor, set->page, bt->mgr->page_size); + else + return 0; + + bt->cursor_page = set->page_no; + + bt_unlockpage(BtLockRead, set->latch); + bt_unpinlatch (set->latch); + return slot; +} + +BtKey *bt_key(BtDb *bt, uint slot) +{ + return keyptr(bt->cursor, slot); +} + +BtVal *bt_val(BtDb *bt, uint slot) +{ + return valptr(bt->cursor,slot); +} + +#ifdef STANDALONE + +#ifndef unix +double getCpuTime(int type) +{ +FILETIME crtime[1]; +FILETIME xittime[1]; +FILETIME systime[1]; +FILETIME usrtime[1]; +SYSTEMTIME timeconv[1]; +double ans = 0; + + memset (timeconv, 0, sizeof(SYSTEMTIME)); + + switch( type ) { + case 0: + GetSystemTimeAsFileTime (xittime); + FileTimeToSystemTime (xittime, timeconv); + ans = (double)timeconv->wDayOfWeek * 3600 * 24; + break; + case 1: + GetProcessTimes (GetCurrentProcess(), crtime, xittime, systime, usrtime); + FileTimeToSystemTime (usrtime, timeconv); + break; + case 2: + GetProcessTimes (GetCurrentProcess(), crtime, xittime, systime, usrtime); + FileTimeToSystemTime (systime, timeconv); + break; + } + + ans += (double)timeconv->wHour * 3600; + ans += (double)timeconv->wMinute * 60; + ans += (double)timeconv->wSecond; + ans += (double)timeconv->wMilliseconds / 1000; + return ans; +} +#else +#include +#include + +double getCpuTime(int type) +{ +struct rusage used[1]; +struct timeval tv[1]; + + switch( type ) { + case 0: + gettimeofday(tv, NULL); + return (double)tv->tv_sec + (double)tv->tv_usec / 1000000; + + case 1: + getrusage(RUSAGE_SELF, used); + return (double)used->ru_utime.tv_sec + (double)used->ru_utime.tv_usec / 1000000; + + case 2: + getrusage(RUSAGE_SELF, used); + return (double)used->ru_stime.tv_sec + (double)used->ru_stime.tv_usec / 1000000; + } + + return 0; +} +#endif + +void bt_poolaudit (BtMgr *mgr) +{ +BtLatchSet *latch; +uint slot = 0; + + while( slot++ < mgr->latchdeployed ) { + latch = mgr->latchsets + slot; + + if( *latch->readwr->rin & MASK ) + fprintf(stderr, "latchset %d rwlocked for page %.8x\n", slot, latch->page_no); + memset ((ushort *)latch->readwr, 0, sizeof(RWLock)); + + if( *latch->access->rin & MASK ) + fprintf(stderr, "latchset %d accesslocked for page %.8x\n", slot, latch->page_no); + memset ((ushort *)latch->access, 0, sizeof(RWLock)); + + if( *latch->parent->rin & MASK ) + fprintf(stderr, "latchset %d parentlocked for page %.8x\n", slot, latch->page_no); + memset ((ushort *)latch->parent, 0, sizeof(RWLock)); + + if( latch->pin & ~CLOCK_bit ) { + fprintf(stderr, "latchset %d pinned for page %.8x\n", slot, latch->page_no); + latch->pin = 0; + } + } +} + +uint bt_latchaudit (BtDb *bt) +{ +ushort idx, hashidx; +uid next, page_no; +BtLatchSet *latch; +uint cnt = 0; +BtKey *ptr; + + if( *(ushort *)(bt->mgr->alloclatch) ) + fprintf(stderr, "Alloc page locked\n"); + *(uint *)(bt->mgr->alloclatch) = 0; + + for( idx = 1; idx <= bt->mgr->latchdeployed; idx++ ) { + latch = bt->mgr->latchsets + idx; + if( *latch->readwr->rin & MASK ) + fprintf(stderr, "latchset %d rwlocked for page %.8x\n", idx, latch->page_no); + memset ((ushort *)latch->readwr, 0, sizeof(RWLock)); + + if( *latch->access->rin & MASK ) + fprintf(stderr, "latchset %d accesslocked for page %.8x\n", idx, latch->page_no); + memset ((ushort *)latch->access, 0, sizeof(RWLock)); + + if( *latch->parent->rin & MASK ) + fprintf(stderr, "latchset %d parentlocked for page %.8x\n", idx, latch->page_no); + memset ((ushort *)latch->parent, 0, sizeof(RWLock)); + + if( latch->pin ) { + fprintf(stderr, "latchset %d pinned for page %.8x\n", idx, latch->page_no); + latch->pin = 0; + } + } + + for( hashidx = 0; hashidx < bt->mgr->latchhash; hashidx++ ) { + if( *(uint *)(bt->mgr->hashtable[hashidx].latch) ) + fprintf(stderr, "hash entry %d locked\n", hashidx); + + *(uint *)(bt->mgr->hashtable[hashidx].latch) = 0; + + if( idx = bt->mgr->hashtable[hashidx].slot ) do { + latch = bt->mgr->latchsets + idx; + if( latch->pin ) + fprintf(stderr, "latchset %d pinned for page %.8x\n", idx, latch->page_no); + } while( idx = latch->next ); + } + + page_no = LEAF_page; + + while( page_no < bt_getid(bt->mgr->pagezero->alloc->right) ) { + uid off = page_no << bt->mgr->page_bits; +#ifdef unix + pread (bt->mgr->idx, bt->frame, bt->mgr->page_size, off); +#else + DWORD amt[1]; + + SetFilePointer (bt->mgr->idx, (long)off, (long*)(&off)+1, FILE_BEGIN); + + if( !ReadFile(bt->mgr->idx, bt->frame, bt->mgr->page_size, amt, NULL)) + return bt->err = BTERR_map; + + if( *amt < bt->mgr->page_size ) + return bt->err = BTERR_map; +#endif + if( !bt->frame->free && !bt->frame->lvl ) + cnt += bt->frame->act; + page_no++; + } + + cnt--; // remove stopper key + fprintf(stderr, " Total keys read %d\n", cnt); + + bt_close (bt); + return 0; +} + +typedef struct { + char idx; + char *type; + char *infile; + BtMgr *mgr; +} ThreadArg; + +// standalone program to index file of keys +// then list them onto std-out + +#ifdef unix +void *index_file (void *arg) +#else +uint __stdcall index_file (void *arg) +#endif +{ +int line = 0, found = 0, cnt = 0, unique; +uid next, page_no = LEAF_page; // start on first page of leaves +BtPage page = calloc (4096, 1); +unsigned char key[BT_maxkey]; +ThreadArg *args = arg; +int ch, len = 0, slot; +BtPageSet set[1]; +int atomic; +BtKey *ptr; +BtVal *val; +BtDb *bt; +FILE *in; + + bt = bt_open (args->mgr); + + unique = (args->type[1] | 0x20) != 'd'; + atomic = (args->type[1] | 0x20) == 'a'; + + switch(args->type[0] | 0x20) + { + case 'a': + fprintf(stderr, "started latch mgr audit\n"); + cnt = bt_latchaudit (bt); + fprintf(stderr, "finished latch mgr audit, found %d keys\n", cnt); + break; + + case 'p': + fprintf(stderr, "started pennysort for %s\n", args->infile); + if( in = fopen (args->infile, "rb") ) + while( ch = getc(in), ch != EOF ) + if( ch == '\n' ) + { + line++; + + if( atomic ) { + memset (page, 0, 4096); + slotptr(page, 1)->off = 2048; + slotptr(page, 1)->type = Unique; + ptr = keyptr(page,1); + ptr->len = 10; + memcpy(ptr->key, key, 10); + val = valptr(page,1); + val->len = len - 10; + memcpy (val->value, key + 10, len - 10); + page->cnt = 1; + if( slot = bt_atomicinsert (bt, page) ) + fprintf(stderr, "Error %d Line: %d\n", slot, line), exit(0); + } + else if( bt_insertkey (bt, key, 10, 0, key + 10, len - 10, unique) ) + fprintf(stderr, "Error %d Line: %d\n", bt->err, line), exit(0); + len = 0; + } + else if( len < BT_maxkey ) + key[len++] = ch; + fprintf(stderr, "finished %s for %d keys: %d reads %d writes\n", args->infile, line, bt->reads, bt->writes); + break; + + case 'w': + fprintf(stderr, "started indexing for %s\n", args->infile); + if( in = fopen (args->infile, "rb") ) + while( ch = getc(in), ch != EOF ) + if( ch == '\n' ) + { + line++; + if( bt_insertkey (bt, key, len, 0, NULL, 0, unique) ) + fprintf(stderr, "Error %d Line: %d\n", bt->err, line), exit(0); + len = 0; + } + else if( len < BT_maxkey ) + key[len++] = ch; + fprintf(stderr, "finished %s for %d keys: %d reads %d writes\n", args->infile, line, bt->reads, bt->writes); + break; + + case 'd': + fprintf(stderr, "started deleting keys for %s\n", args->infile); + if( in = fopen (args->infile, "rb") ) + while( ch = getc(in), ch != EOF ) + if( ch == '\n' ) + { + line++; + if( bt_findkey (bt, key, len, NULL, 0) < 0 ) + fprintf(stderr, "Cannot find key for Line: %d\n", line), exit(0); + ptr = (BtKey*)(bt->key); + found++; + + if( bt_deletekey (bt, ptr->key, ptr->len, 0) ) + fprintf(stderr, "Error %d Line: %d\n", bt->err, line), exit(0); + len = 0; + } + else if( len < BT_maxkey ) + key[len++] = ch; + fprintf(stderr, "finished %s for %d keys, %d found: %d reads %d writes\n", args->infile, line, found, bt->reads, bt->writes); + break; + + case 'f': + fprintf(stderr, "started finding keys for %s\n", args->infile); + if( in = fopen (args->infile, "rb") ) + while( ch = getc(in), ch != EOF ) + if( ch == '\n' ) + { + line++; + if( bt_findkey (bt, key, len, NULL, 0) == 0 ) + found++; + else if( bt->err ) + fprintf(stderr, "Error %d Syserr %d Line: %d\n", bt->err, errno, line), exit(0); + len = 0; + } + else if( len < BT_maxkey ) + key[len++] = ch; + fprintf(stderr, "finished %s for %d keys, found %d: %d reads %d writes\n", args->infile, line, found, bt->reads, bt->writes); + break; + + case 's': + fprintf(stderr, "started scanning\n"); + do { + if( set->latch = bt_pinlatch (bt, page_no, 1) ) + set->page = bt_mappage (bt, set->latch); + else + fprintf(stderr, "unable to obtain latch"), exit(1); + bt_lockpage (BtLockRead, set->latch); + next = bt_getid (set->page->right); + + for( slot = 0; slot++ < set->page->cnt; ) + if( next || slot < set->page->cnt ) + if( !slotptr(set->page, slot)->dead ) { + ptr = keyptr(set->page, slot); + len = ptr->len; + + if( slotptr(set->page, slot)->type == Duplicate ) + len -= BtId; + + fwrite (ptr->key, len, 1, stdout); + val = valptr(set->page, slot); + fwrite (val->value, val->len, 1, stdout); + fputc ('\n', stdout); + cnt++; + } + + bt_unlockpage (BtLockRead, set->latch); + bt_unpinlatch (set->latch); + } while( page_no = next ); + + fprintf(stderr, " Total keys read %d: %d reads, %d writes\n", cnt, bt->reads, bt->writes); + break; + + case 'r': + fprintf(stderr, "started reverse scan\n"); + if( slot = bt_lastkey (bt) ) + while( slot = bt_prevkey (bt, slot) ) { + if( slotptr(bt->cursor, slot)->dead ) + continue; + + ptr = keyptr(bt->cursor, slot); + len = ptr->len; + + if( slotptr(bt->cursor, slot)->type == Duplicate ) + len -= BtId; + + fwrite (ptr->key, len, 1, stdout); + val = valptr(bt->cursor, slot); + fwrite (val->value, val->len, 1, stdout); + fputc ('\n', stdout); + cnt++; + } + + fprintf(stderr, " Total keys read %d: %d reads, %d writes\n", cnt, bt->reads, bt->writes); + break; + + case 'c': +#ifdef unix + posix_fadvise( bt->mgr->idx, 0, 0, POSIX_FADV_SEQUENTIAL); +#endif + fprintf(stderr, "started counting\n"); + page_no = LEAF_page; + + while( page_no < bt_getid(bt->mgr->pagezero->alloc->right) ) { + if( bt_readpage (bt->mgr, bt->frame, page_no) ) + break; + + if( !bt->frame->free && !bt->frame->lvl ) + cnt += bt->frame->act; + + bt->reads++; + page_no++; + } + + cnt--; // remove stopper key + fprintf(stderr, " Total keys read %d: %d reads, %d writes\n", cnt, bt->reads, bt->writes); + break; + } + + bt_close (bt); +#ifdef unix + return NULL; +#else + return 0; +#endif +} + +typedef struct timeval timer; + +int main (int argc, char **argv) +{ +int idx, cnt, len, slot, err; +int segsize, bits = 16; +double start, stop; +#ifdef unix +pthread_t *threads; +#else +HANDLE *threads; +#endif +ThreadArg *args; +uint poolsize = 0; +uint locksize = 0; +float elapsed; +char key[1]; +BtMgr *mgr; +BtKey *ptr; +BtDb *bt; + + if( argc < 3 ) { + fprintf (stderr, "Usage: %s idx_file Read/Write/Scan/Delete/Find/Atomic [page_bits buffer_pool_size lock_mgr_size src_file1 src_file2 ... ]\n", argv[0]); + fprintf (stderr, " where page_bits is the page size in bits\n"); + fprintf (stderr, " buffer_pool_size is the number of pages in buffer pool\n"); + fprintf (stderr, " lock_mgr_size is the maximum number of outstanding key locks\n"); + fprintf (stderr, " src_file1 thru src_filen are files of keys separated by newline\n"); + exit(0); + } + + start = getCpuTime(0); + + if( argc > 3 ) + bits = atoi(argv[3]); + + if( argc > 4 ) + poolsize = atoi(argv[4]); + + if( !poolsize ) + fprintf (stderr, "Warning: no mapped_pool\n"); + + if( argc > 5 ) + locksize = atoi(argv[5]); + + cnt = argc - 6; +#ifdef unix + threads = malloc (cnt * sizeof(pthread_t)); +#else + threads = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, cnt * sizeof(HANDLE)); +#endif + args = malloc (cnt * sizeof(ThreadArg)); + + mgr = bt_mgr ((argv[1]), bits, poolsize, locksize); + + if( !mgr ) { + fprintf(stderr, "Index Open Error %s\n", argv[1]); + exit (1); + } + + // fire off threads + + for( idx = 0; idx < cnt; idx++ ) { + args[idx].infile = argv[idx + 6]; + args[idx].type = argv[2]; + args[idx].mgr = mgr; + args[idx].idx = idx; +#ifdef unix + if( err = pthread_create (threads + idx, NULL, index_file, args + idx) ) + fprintf(stderr, "Error creating thread %d\n", err); +#else + threads[idx] = (HANDLE)_beginthreadex(NULL, 65536, index_file, args + idx, 0, NULL); +#endif + } + + // wait for termination + +#ifdef unix + for( idx = 0; idx < cnt; idx++ ) + pthread_join (threads[idx], NULL); +#else + WaitForMultipleObjects (cnt, threads, TRUE, INFINITE); + + for( idx = 0; idx < cnt; idx++ ) + CloseHandle(threads[idx]); + +#endif + bt_poolaudit(mgr); + bt_mgrclose (mgr); + + elapsed = getCpuTime(0) - start; + fprintf(stderr, " real %dm%.3fs\n", (int)(elapsed/60), elapsed - (int)(elapsed/60)*60); + elapsed = getCpuTime(1); + fprintf(stderr, " user %dm%.3fs\n", (int)(elapsed/60), elapsed - (int)(elapsed/60)*60); + elapsed = getCpuTime(2); + fprintf(stderr, " sys %dm%.3fs\n", (int)(elapsed/60), elapsed - (int)(elapsed/60)*60); +} + +#endif //STANDALONE -- 2.40.0