From 680a12ba5215c2b00d2c7088289c871a95849c47 Mon Sep 17 00:00:00 2001 From: unknown Date: Fri, 17 Oct 2014 16:39:41 -0700 Subject: [PATCH] Rewrite re-entrant phase-fair latching, continue LSM btree code --- threadskv10b.c | 3794 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 3794 insertions(+) create mode 100644 threadskv10b.c diff --git a/threadskv10b.c b/threadskv10b.c new file mode 100644 index 0000000..825b5f5 --- /dev/null +++ b/threadskv10b.c @@ -0,0 +1,3794 @@ +// btree version threadskv10b futex version +// with reworked bt_deletekey code, +// phase-fair re-entrant reader writer locks, +// librarian page split code, +// duplicate key management +// bi-directional cursors +// traditional buffer pool manager +// ACID batched key-value updates +// redo log for failure recovery +// and LSM B-trees for write optimization + +// 17 OCT 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 +#include +#define SYS_futex 202 +#endif + +#ifdef unix +#include +#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; +typedef unsigned long long logseqno; + +#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 26 // 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 +#define REDO_page 3 // first page of redo buffer + +// Number of levels to create in a new BTree + +#define MIN_lvl 2 + +/* +There are six lock types for each node in four 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. +6. (set 4) AtomicModification: Exclusive. Atomic Update including node is underway. Incompatible with another AtomicModification. +*/ + +typedef enum{ + BtLockAccess = 1, + BtLockDelete = 2, + BtLockRead = 4, + BtLockWrite = 8, + BtLockParent = 16, + BtLockAtomic = 32, + BtLockLink = 64 +} BtLock; + +typedef struct { + union { + struct { + volatile ushort xlock[1]; // one writer has exclusive lock + volatile ushort wrt[1]; // count of other writers waiting + } bits[1]; + uint value[1]; + }; +} BtMutexLatch; + +#define XCL 1 +#define WRT 65536 + +// definition for reader/writer reentrant lock implementation + +typedef struct { + BtMutexLatch xcl[1]; + union { + struct { + volatile ushort tid[1]; + volatile ushort readers[1]; + } bits[1]; + uint value[1]; + }; + volatile ushort waitwrite[1]; + volatile ushort waitread[1]; + volatile ushort phase[1]; // phase == 1 for reading after write + volatile ushort dup[1]; // reentrant counter +} RWLock; + +// write only reentrant lock + +typedef struct { + BtMutexLatch xcl[1]; + union { + struct { + volatile ushort tid[1]; + volatile ushort dup[1]; + } bits[1]; + uint value[1]; + }; + volatile uint waiters[1]; +} WOLock; + +// mode & definition for lite latch implementation + +enum { + QueRd = 1, // reader queue + QueWr = 2 // writer queue +} RWQueue; + +// hash table entries + +typedef struct { + uint entry; // Latch table entry at head of chain + BtMutexLatch 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 + RWLock atomic[1]; // Atomic update in progress + RWLock link[1]; // left link being updated + uint split; // right split page atomic insert + uint next; // next entry in hash table chain + uint prev; // prev entry in hash table chain + ushort pin; // number of accessing threads + unsigned char dirty; // page in cache is dirty (atomic setable) + BtMutexLatch modify[1]; // modify entry lite latch +} BtLatchSet; + +// 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, + Delete +} 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 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; + +#define BT_maxkey 255 // maximum number of bytes in a key +#define BT_keyarray (BT_maxkey + sizeof(BtKey)) + +// 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 PageZero 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 right[BtId]; // page number to right + unsigned char left[BtId]; // page number to left + unsigned char filler[2]; // padding to multiple of 8 + logseqno lsn; // log sequence number applied + uid page_no; // this page number +} *BtPage; + +// The loadpage interface object + +typedef struct { + 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 char freechain[BtId]; // head of free page_nos chain + unsigned long long activepages; // number of active pages + uint redopages; // number of redo pages in file +} 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 + BtHashEntry *hashtable; // the buffer pool hash table entries + BtLatchSet *latchsets; // mapped latch set from buffer pool + unsigned char *pagepool; // mapped to the buffer pool pages + unsigned char *redobuff; // mapped recovery buffer pointer + logseqno lsn, flushlsn; // current & first lsn flushed + BtMutexLatch redo[1]; // redo area lite latch + BtMutexLatch lock[1]; // allocation area lite latch + BtMutexLatch maps[1]; // mapping segments lite latch + ushort thread_no[1]; // next thread number + uint nlatchpage; // number of latch pages at BT_latch + uint latchtotal; // number of page latch entries + uint latchhash; // number of latch hash table slots + uint latchvictim; // next latch entry to examine + uint latchpromote; // next latch entry to promote + uint redolast; // last msync size of recovery buff + uint redoend; // eof/end element in recovery buff + int err; // last error + int line; // last error line no + int found; // number of keys found by delete + int reads, writes; // number of reads and writes +#ifndef unix + HANDLE halloc; // allocation handle + HANDLE hpool; // buffer pool handle +#endif + uint segments; // number of memory mapped segments + unsigned char *pages[64000];// memory mapped segments of b-tree +} BtMgr; + +typedef struct { + BtMgr *mgr; // buffer manager for entire process + BtMgr *main; // buffer manager for main btree + BtPage frame; // cached page frame for promote + BtPage cursor; // cached page frame for start/next + ushort thread_no; // thread number + unsigned char key[BT_keyarray]; // last found complete key +} BtDb; + +// atomic txn structures + +typedef struct { + logseqno reqlsn; // redo log seq no required + uint entry; // latch table entry number + uint slot:31; // page slot number + uint reuse:1; // reused previous page +} AtomicTxn; + +// Catastrophic errors + +typedef enum { + BTERR_ok = 0, + BTERR_struct, + BTERR_ovflw, + BTERR_lock, + BTERR_map, + BTERR_read, + BTERR_wrt, + BTERR_atomic, + BTERR_recovery +} BTERR; + +#define CLOCK_bit 0x8000 + +// recovery manager entry types + +typedef enum { + BTRM_eof = 0, // rest of buffer is emtpy + BTRM_add, // add a unique key-value to btree + BTRM_dup, // add a duplicate key-value to btree + BTRM_del, // delete a key-value from btree + BTRM_upd, // update a key with a new value + BTRM_new, // allocate a new empty page + BTRM_old // reuse an old empty page +} BTRM; + +// recovery manager entry +// structure followed by BtKey & BtVal + +typedef struct { + logseqno reqlsn; // log sequence number required + logseqno lsn; // log sequence number for entry + uint len; // length of entry + unsigned char type; // type of entry + unsigned char lvl; // level of btree entry pertains to +} BtLogHdr; + +// B-Tree functions + +extern void bt_close (BtDb *bt); +extern BtDb *bt_open (BtMgr *mgr, BtMgr *main); +extern BTERR bt_writepage (BtMgr *mgr, BtPage page, uid page_no); +extern BTERR bt_readpage (BtMgr *mgr, BtPage page, uid page_no); +extern void bt_lockpage(BtLock mode, BtLatchSet *latch, ushort thread_no); +extern void bt_unlockpage(BtLock mode, BtLatchSet *latch); +extern BTERR bt_insertkey (BtMgr *mgr, unsigned char *key, uint len, uint lvl, void *value, uint vallen, BtSlotType type, ushort thread_no); +extern BTERR bt_deletekey (BtMgr *mgr, unsigned char *key, uint len, uint lvl, ushort thread_no); + +extern int bt_findkey (BtDb *db, unsigned char *key, uint keylen, unsigned char *value, uint valmax); + +extern uint bt_startkey (BtDb *db, unsigned char *key, uint len); +extern uint bt_nextkey (BtDb *bt, uint slot); +extern uint bt_prevkey (BtDb *db, uint slot); +extern uint bt_lastkey (BtDb *db); + +// manager functions +extern BtMgr *bt_mgr (char *name, uint bits, uint poolsize, uint redopages); +extern void bt_mgrclose (BtMgr *mgr); +extern logseqno bt_newredo (BtMgr *mgr, BTRM type, int lvl, BtKey *key, BtVal *val, ushort thread_no); +extern logseqno bt_txnredo (BtMgr *mgr, BtPage page, ushort thread_no); + +// atomic transaction functions +BTERR bt_atomicexec(BtMgr *mgr, BtPage source, logseqno lsn, int lsm, ushort thread_no); +BTERR bt_txnpromote (BtDb *bt); + +// 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; +} + +// lite weight spin lock Latch Manager + +int sys_futex(void *addr1, int op, int val1, struct timespec *timeout, void *addr2, int val3) +{ + return syscall(SYS_futex, addr1, op, val1, timeout, addr2, val3); +} + +void bt_mutexlock(BtMutexLatch *latch) +{ +BtMutexLatch prev[1]; +uint slept = 0; + + while( 1 ) { + *prev->value = __sync_fetch_and_or(latch->value, XCL); + + if( !*prev->bits->xlock ) { // did we set XCL? + if( slept ) + __sync_fetch_and_sub(latch->value, WRT); + return; + } + + if( !slept ) { + *prev->bits->wrt += 1; + __sync_fetch_and_add(latch->value, WRT); + } + + sys_futex (latch->value, FUTEX_WAIT_BITSET_PRIVATE, *prev->value, NULL, NULL, QueWr); + slept = 1; + } +} + +// try to obtain write lock + +// return 1 if obtained, +// 0 otherwise + +int bt_mutextry(BtMutexLatch *latch) +{ +BtMutexLatch prev[1]; + + *prev->value = __sync_fetch_and_or(latch->value, XCL); + + // take write access if exclusive bit was clear + + return !*prev->bits->xlock; +} + +// clear write mode + +void bt_releasemutex(BtMutexLatch *latch) +{ +BtMutexLatch prev[1]; + + *prev->value = __sync_fetch_and_and(latch->value, ~XCL); + + if( *prev->bits->wrt ) + sys_futex( latch->value, FUTEX_WAKE_BITSET_PRIVATE, 1, NULL, NULL, QueWr ); +} + +// reentrant reader/writer lock implementation + +void WriteLock (RWLock *lock, ushort tid) +{ +uint waited = 0; +RWLock prev[1]; + + while( 1 ) { + bt_mutexlock(lock->xcl); + *prev = *lock; + + // is this a re-entrant request? + + if( *prev->bits->tid == tid ) + *prev->dup += 1; + + // wait if write already taken, or there are readers + + else if( *prev->bits->tid || *prev->bits->readers ) { + if( !waited ) + waited++, *lock->waitwrite += 1; + + // otherwise, we can take the lock + + } else { + if( waited ) + *lock->waitwrite -= 1; + + *lock->bits->tid = tid; + *lock->phase = 0; // set writing phase + } + + bt_releasemutex(lock->xcl); + + if( *lock->bits->tid == tid ) + return; + + sys_futex( lock->value, FUTEX_WAIT_BITSET_PRIVATE, *prev->value, NULL, NULL, QueWr ); + } +} + +void WriteRelease (RWLock *lock) +{ + bt_mutexlock(lock->xcl); + + // were we reentrant? + + if( *lock->dup ) { + *lock->dup -= 1; + bt_releasemutex(lock->xcl); + return; + } + + // release write lock and + // set reading after write phase + + *lock->bits->tid = 0; + + // were readers waiting for a write cycle? + + if( *lock->waitread ) { + *lock->phase = 1; + sys_futex( lock->value, FUTEX_WAKE_BITSET_PRIVATE, 32768, NULL, NULL, QueRd ); + + // otherwise were writers waiting + + } else if( *lock->waitwrite ) { + *lock->phase = 0; + sys_futex( lock->value, FUTEX_WAKE_BITSET_PRIVATE, 1, NULL, NULL, QueWr ); + } + + bt_releasemutex(lock->xcl); +} + +void ReadLock (RWLock *lock, ushort tid) +{ +uint xit, waited = 0; +RWLock prev[1]; + + while( 1 ) { + bt_mutexlock(lock->xcl); + *prev = *lock; + xit = 0; + + // wait if a write lock is currenty active + // or we are not in a new read cycle and + // writers are waiting. + + if( *prev->bits->tid || !*prev->phase && *prev->waitwrite ) { + if( !waited ) + waited++, *lock->waitread += 1; + + // else we can take the lock + + } else { + if( waited ) + *lock->waitread -= 1; + + *lock->bits->readers += 1; + xit = 1; + } + + bt_releasemutex(lock->xcl); + + // did we increment readers? + + if( xit ) + return; + + sys_futex( lock->value, FUTEX_WAIT_BITSET_PRIVATE, *prev->value, NULL, NULL, QueRd ); + } +} + +void ReadRelease (RWLock *lock) +{ +RWLock prev[1]; + + bt_mutexlock(lock->xcl); + *prev = *lock; + + *prev->bits->readers = *lock->bits->readers -= 1; + + if( !*lock->waitread && *lock->waitwrite ) + *prev->phase = *lock->phase = 0; // stop accepting new readers + + bt_releasemutex(lock->xcl); + + // were writers waiting for a read cycle to finish? + + if( !*prev->phase && !*prev->bits->readers ) + if( *prev->waitwrite ) + sys_futex( lock->value, FUTEX_WAKE_BITSET_PRIVATE, 1, NULL, NULL, QueWr ); +} + +// recovery manager -- flush dirty pages + +void bt_flushlsn (BtMgr *mgr, ushort thread_no) +{ +uint cnt3 = 0, cnt2 = 0, cnt = 0; +uint entry, segment; +BtLatchSet *latch; +BtPage page; + + // flush dirty pool pages to the btree + +fprintf(stderr, "Start flushlsn "); + for( entry = 1; entry < mgr->latchtotal; entry++ ) { + page = (BtPage)(((uid)entry << mgr->page_bits) + mgr->pagepool); + latch = mgr->latchsets + entry; + bt_mutexlock (latch->modify); + bt_lockpage(BtLockRead, latch, thread_no); + + if( latch->dirty ) { + bt_writepage(mgr, page, latch->page_no); + latch->dirty = 0, cnt++; + } +if( latch->pin & ~CLOCK_bit ) +cnt2++; + bt_unlockpage(BtLockRead, latch); + bt_releasemutex (latch->modify); + } +fprintf(stderr, "End flushlsn %d pages %d pinned\n", cnt, cnt2); +fprintf(stderr, "begin sync"); + for( segment = 0; segment < mgr->segments; segment++ ) + if( msync (mgr->pages[segment], (uid)65536 << mgr->page_bits, MS_SYNC) < 0 ) + fprintf(stderr, "msync error %d line %d\n", errno, __LINE__); +fprintf(stderr, " end sync\n"); +} + +// recovery manager -- process current recovery buff on startup +// this won't do much if previous session was properly closed. + +BTERR bt_recoveryredo (BtMgr *mgr) +{ +BtLogHdr *hdr, *eof; +uint offset = 0; +BtKey *key; +BtVal *val; + + hdr = (BtLogHdr *)mgr->redobuff; + mgr->flushlsn = hdr->lsn; + + while( 1 ) { + hdr = (BtLogHdr *)(mgr->redobuff + offset); + switch( hdr->type ) { + case BTRM_eof: + mgr->lsn = hdr->lsn; + return 0; + case BTRM_add: // add a unique key-value to btree + + case BTRM_dup: // add a duplicate key-value to btree + case BTRM_del: // delete a key-value from btree + case BTRM_upd: // update a key with a new value + case BTRM_new: // allocate a new empty page + case BTRM_old: // reuse an old empty page + return 0; + } + } +} + +// recovery manager -- append new entry to recovery log +// flush dirty pages to disk when it overflows. + +logseqno bt_newredo (BtMgr *mgr, BTRM type, int lvl, BtKey *key, BtVal *val, ushort thread_no) +{ +uint size = mgr->page_size * mgr->pagezero->redopages - sizeof(BtLogHdr); +uint amt = sizeof(BtLogHdr); +BtLogHdr *hdr, *eof; +uint last, end; + + bt_mutexlock (mgr->redo); + + if( key ) + amt += key->len + val->len + sizeof(BtKey) + sizeof(BtVal); + + // see if new entry fits in buffer + // flush and reset if it doesn't + + if( amt > size - mgr->redoend ) { + mgr->flushlsn = mgr->lsn; + if( msync (mgr->redobuff + (mgr->redolast & ~0xfff), mgr->redoend - (mgr->redolast & ~0xfff) + sizeof(BtLogHdr), MS_SYNC) < 0 ) + fprintf(stderr, "msync error %d line %d\n", errno, __LINE__); + mgr->redolast = 0; + mgr->redoend = 0; + bt_flushlsn(mgr, thread_no); + } + + // fill in new entry & either eof or end block + + hdr = (BtLogHdr *)(mgr->redobuff + mgr->redoend); + + hdr->len = amt; + hdr->type = type; + hdr->lvl = lvl; + hdr->lsn = ++mgr->lsn; + + mgr->redoend += amt; + + eof = (BtLogHdr *)(mgr->redobuff + mgr->redoend); + memset (eof, 0, sizeof(BtLogHdr)); + + // fill in key and value + + if( key ) { + memcpy ((unsigned char *)(hdr + 1), key, key->len + sizeof(BtKey)); + memcpy ((unsigned char *)(hdr + 1) + key->len + sizeof(BtKey), val, val->len + sizeof(BtVal)); + } + + eof = (BtLogHdr *)(mgr->redobuff + mgr->redoend); + memset (eof, 0, sizeof(BtLogHdr)); + eof->lsn = mgr->lsn; + + last = mgr->redolast & ~0xfff; + end = mgr->redoend; + + if( end - last + sizeof(BtLogHdr) >= 32768 ) + if( msync (mgr->redobuff + last, end - last + sizeof(BtLogHdr), MS_SYNC) < 0 ) + fprintf(stderr, "msync error %d line %d\n", errno, __LINE__); + else + mgr->redolast = end; + + bt_releasemutex(mgr->redo); + return hdr->lsn; +} + +// recovery manager -- append transaction to recovery log +// flush dirty pages to disk when it overflows. + +logseqno bt_txnredo (BtMgr *mgr, BtPage source, ushort thread_no) +{ +uint size = mgr->page_size * mgr->pagezero->redopages - sizeof(BtLogHdr); +uint amt = 0, src, type; +BtLogHdr *hdr, *eof; +uint last, end; +logseqno lsn; +BtKey *key; +BtVal *val; + + // determine amount of redo recovery log space required + + for( src = 0; src++ < source->cnt; ) { + key = keyptr(source,src); + val = valptr(source,src); + amt += key->len + val->len + sizeof(BtKey) + sizeof(BtVal); + amt += sizeof(BtLogHdr); + } + + bt_mutexlock (mgr->redo); + + // see if new entry fits in buffer + // flush and reset if it doesn't + + if( amt > size - mgr->redoend ) { + mgr->flushlsn = mgr->lsn; + if( msync (mgr->redobuff + (mgr->redolast & ~0xfff), mgr->redoend - (mgr->redolast & ~0xfff) + sizeof(BtLogHdr), MS_SYNC) < 0 ) + fprintf(stderr, "msync error %d line %d\n", errno, __LINE__); + mgr->redolast = 0; + mgr->redoend = 0; + bt_flushlsn (mgr, thread_no); + } + + // assign new lsn to transaction + + lsn = ++mgr->lsn; + + // fill in new entries + + for( src = 0; src++ < source->cnt; ) { + key = keyptr(source, src); + val = valptr(source, src); + + switch( slotptr(source, src)->type ) { + case Unique: + type = BTRM_add; + break; + case Duplicate: + type = BTRM_dup; + break; + case Delete: + type = BTRM_del; + break; + } + + amt = key->len + val->len + sizeof(BtKey) + sizeof(BtVal); + amt += sizeof(BtLogHdr); + + hdr = (BtLogHdr *)(mgr->redobuff + mgr->redoend); + hdr->len = amt; + hdr->type = type; + hdr->lsn = lsn; + hdr->lvl = 0; + + // fill in key and value + + memcpy ((unsigned char *)(hdr + 1), key, key->len + sizeof(BtKey)); + memcpy ((unsigned char *)(hdr + 1) + key->len + sizeof(BtKey), val, val->len + sizeof(BtVal)); + + mgr->redoend += amt; + } + + eof = (BtLogHdr *)(mgr->redobuff + mgr->redoend); + memset (eof, 0, sizeof(BtLogHdr)); + eof->lsn = lsn; + + last = mgr->redolast & ~0xfff; + end = mgr->redoend; + + if( end - last + sizeof(BtLogHdr) >= 32768 ) + if( msync (mgr->redobuff + last, end - last + sizeof(BtLogHdr), MS_SYNC) < 0 ) + fprintf(stderr, "msync error %d line %d\n", errno, __LINE__); + else + mgr->redolast = end; + + bt_releasemutex(mgr->redo); + return lsn; +} + +// sync a single btree page to disk + +BTERR bt_syncpage (BtMgr *mgr, BtPage page, BtLatchSet *latch) +{ +uint segment = latch->page_no >> 16; +BtPage perm; + + if( bt_writepage (mgr, page, latch->page_no) ) + return mgr->err; + + perm = (BtPage)(mgr->pages[segment] + ((latch->page_no & 0xffff) << mgr->page_bits)); + + if( msync (perm, mgr->page_size, MS_SYNC) < 0 ) + fprintf(stderr, "msync error %d line %d\n", errno, __LINE__); + + latch->dirty = 0; + return 0; +} + +// read page into buffer pool from permanent location in Btree file + +BTERR bt_readpage (BtMgr *mgr, BtPage page, uid page_no) +{ +int flag = PROT_READ | PROT_WRITE; +uint segment = page_no >> 16; +BtPage perm; + + while( 1 ) { + if( segment < mgr->segments ) { + perm = (BtPage)(mgr->pages[segment] + ((page_no & 0xffff) << mgr->page_bits)); + + memcpy (page, perm, mgr->page_size); + mgr->reads++; + return 0; + } + + bt_mutexlock (mgr->maps); + + if( segment < mgr->segments ) { + bt_releasemutex (mgr->maps); + continue; + } + + mgr->pages[mgr->segments] = mmap (0, (uid)65536 << mgr->page_bits, flag, MAP_SHARED, mgr->idx, (uid)mgr->segments << (mgr->page_bits + 16)); + mgr->segments++; + + bt_releasemutex (mgr->maps); + } +} + +// write page to permanent location in Btree file +// clear the dirty bit + +BTERR bt_writepage (BtMgr *mgr, BtPage page, uid page_no) +{ +int flag = PROT_READ | PROT_WRITE; +uint segment = page_no >> 16; +BtPage perm; + + while( 1 ) { + if( segment < mgr->segments ) { + perm = (BtPage)(mgr->pages[segment] + ((page_no & 0xffff) << mgr->page_bits)); + + memcpy (perm, page, mgr->page_size); + mgr->writes++; + return 0; + } + + bt_mutexlock (mgr->maps); + + if( segment < mgr->segments ) { + bt_releasemutex (mgr->maps); + continue; + } + + mgr->pages[mgr->segments] = mmap (0, (uid)65536 << mgr->page_bits, flag, MAP_SHARED, mgr->idx, (uid)mgr->segments << (mgr->page_bits + 16)); + bt_releasemutex (mgr->maps); + mgr->segments++; + } +} + +// set CLOCK bit in latch +// decrement pin count + +void bt_unpinlatch (BtMgr *mgr, BtLatchSet *latch) +{ + bt_mutexlock(latch->modify); + latch->pin |= CLOCK_bit; + latch->pin--; + + bt_releasemutex(latch->modify); +} + +// return the btree cached page address + +BtPage bt_mappage (BtMgr *mgr, BtLatchSet *latch) +{ +uid entry = latch - mgr->latchsets; +BtPage page = (BtPage)((entry << mgr->page_bits) + mgr->pagepool); + + return page; +} + +// return next available latch entry +// and with latch entry locked + +uint bt_availnext (BtMgr *mgr) +{ +BtLatchSet *latch; +uint entry; + + while( 1 ) { +#ifdef unix + entry = __sync_fetch_and_add (&mgr->latchvictim, 1) + 1; +#else + entry = _InterlockedIncrement (&mgr->latchvictim); +#endif + entry %= mgr->latchtotal; + + if( !entry ) + continue; + + latch = mgr->latchsets + entry; + + if( !bt_mutextry(latch->modify) ) + continue; + + // return this entry if it is not pinned + + if( !latch->pin ) + return entry; + + // if the CLOCK bit is set + // reset it to zero. + + latch->pin &= ~CLOCK_bit; + bt_releasemutex(latch->modify); + } +} + +// pin page in buffer pool +// return with latchset pinned + +BtLatchSet *bt_pinlatch (BtMgr *mgr, uid page_no, BtPage contents, ushort thread_id) +{ +uint hashidx = page_no % mgr->latchhash; +BtLatchSet *latch; +uint entry, idx; +BtPage page; + + // try to find our entry + + bt_mutexlock(mgr->hashtable[hashidx].latch); + + if( entry = mgr->hashtable[hashidx].entry ) do + { + latch = mgr->latchsets + entry; + if( page_no == latch->page_no ) + break; + } while( entry = latch->next ); + + // found our entry: increment pin + + if( entry ) { + latch = mgr->latchsets + entry; + bt_mutexlock(latch->modify); + latch->pin |= CLOCK_bit; + latch->pin++; + + bt_releasemutex(latch->modify); + bt_releasemutex(mgr->hashtable[hashidx].latch); + return latch; + } + + // find and reuse unpinned entry + +trynext: + + entry = bt_availnext (mgr); + latch = mgr->latchsets + entry; + + idx = latch->page_no % mgr->latchhash; + + // if latch is on a different hash chain + // unlink from the old page_no chain + + if( latch->page_no ) + if( idx != hashidx ) { + + // skip over this entry if latch not available + + if( !bt_mutextry (mgr->hashtable[idx].latch) ) { + bt_releasemutex(latch->modify); + goto trynext; + } + + if( latch->prev ) + mgr->latchsets[latch->prev].next = latch->next; + else + mgr->hashtable[idx].entry = latch->next; + + if( latch->next ) + mgr->latchsets[latch->next].prev = latch->prev; + + bt_releasemutex (mgr->hashtable[idx].latch); + } + + page = (BtPage)(((uid)entry << mgr->page_bits) + mgr->pagepool); + + // update permanent page area in btree from buffer pool + // no read-lock is required since page is not pinned. + + if( latch->dirty ) + if( mgr->err = bt_writepage (mgr, page, latch->page_no) ) + return mgr->line = __LINE__, NULL; + else + latch->dirty = 0; + + if( contents ) { + memcpy (page, contents, mgr->page_size); + latch->dirty = 1; + } else if( bt_readpage (mgr, page, page_no) ) + return mgr->line = __LINE__, NULL; + + // link page as head of hash table chain + // if this is a never before used entry, + // or it was previously on a different + // hash table chain. Otherwise, just + // leave it in its current hash table + // chain position. + + if( !latch->page_no || hashidx != idx ) { + if( latch->next = mgr->hashtable[hashidx].entry ) + mgr->latchsets[latch->next].prev = entry; + + mgr->hashtable[hashidx].entry = entry; + latch->prev = 0; + } + + // fill in latch structure + + latch->pin = CLOCK_bit | 1; + latch->page_no = page_no; + latch->split = 0; + + bt_releasemutex (latch->modify); + bt_releasemutex (mgr->hashtable[hashidx].latch); + return latch; +} + +void bt_mgrclose (BtMgr *mgr) +{ +BtLatchSet *latch; +BtLogHdr *eof; +uint num = 0; +BtPage page; +uint slot; + + // flush previously written dirty pages + // and write recovery buffer to disk + + fdatasync (mgr->idx); + + if( mgr->redoend ) { + eof = (BtLogHdr *)(mgr->redobuff + mgr->redoend); + memset (eof, 0, sizeof(BtLogHdr)); + } + + // write remaining dirty pool pages to the btree + + for( slot = 1; slot < mgr->latchtotal; 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++; + } + } + + // clear redo recovery buffer on disk. + + if( mgr->pagezero->redopages ) { + eof = (BtLogHdr *)mgr->redobuff; + memset (eof, 0, sizeof(BtLogHdr)); + eof->lsn = mgr->lsn; + if( msync (mgr->redobuff, 4096, MS_SYNC) < 0 ) + fprintf(stderr, "msync error %d line %d\n", errno, __LINE__); + } + + fprintf(stderr, "%d buffer pool pages flushed\n", num); + +#ifdef unix + while( mgr->segments ) + munmap (mgr->pages[--mgr->segments], (uid)65536 << mgr->page_bits); + + munmap (mgr->pagepool, (uid)mgr->nlatchpage << mgr->page_bits); + munmap (mgr->pagezero, mgr->page_size); +#else + FlushViewOfFile(mgr->pagezero, 0); + UnmapViewOfFile(mgr->pagezero); + UnmapViewOfFile(mgr->pagepool); + CloseHandle(mgr->halloc); + CloseHandle(mgr->hpool); +#endif +#ifdef unix + close (mgr->idx); + free (mgr); +#else + VirtualFree (mgr->redobuff, 0, MEM_RELEASE); + FlushFileBuffers(mgr->idx); + CloseHandle(mgr->idx); + GlobalFree (mgr); +#endif +} + +// close and release memory + +void bt_close (BtDb *bt) +{ +#ifdef unix + if( bt->frame ) + free (bt->frame); + if( bt->cursor ) + free (bt->cursor); +#else + if( bt->frame) + VirtualFree (bt->frame, 0, MEM_RELEASE); + if( bt->cursor) + VirtualFree (bt->cursor, 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) + +BtMgr *bt_mgr (char *name, uint bits, uint nodemax, uint redopages) +{ +uint lvl, attr, last, slot, idx; +uint nlatchpage, latchhash; +unsigned char value[BtId]; +int flag, initit = 0; +BtPageZero *pagezero; +BtLatchSet *latch; +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; +#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 create/open btree file %s\n", name); + 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 ) { + fprintf (stderr, "Unable to create/open btree file %s\n", name); + 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 = ((uid)nodemax/16 * sizeof(BtHashEntry) + mgr->page_size - 1) / mgr->page_size; + + mgr->nlatchpage += nodemax; // size of the buffer pool in pages + mgr->nlatchpage += (sizeof(BtLatchSet) * (uid)nodemax + mgr->page_size - 1)/mgr->page_size; + mgr->latchtotal = nodemax; + + 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->lvl = MIN_lvl - 1; + pagezero->alloc->bits = mgr->page_bits; + pagezero->redopages = redopages; + + bt_putid(pagezero->alloc->right, pagezero->redopages + MIN_lvl+1); + pagezero->activepages = 2; + + // initialize left-most LEAF page in + // alloc->left and count of active leaf pages. + + bt_putid (pagezero->alloc->left, LEAF_page); + ftruncate (mgr->idx, (REDO_page + pagezero->redopages) << mgr->page_bits); + + 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--; ) { + BtSlot *node = slotptr(pagezero->alloc, 1); + node->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 = node->off; + pagezero->alloc->lvl = lvl; + pagezero->alloc->cnt = 1; + pagezero->alloc->act = 1; + pagezero->alloc->page_no = MIN_lvl - lvl; + + if( bt_writepage (mgr, pagezero->alloc, MIN_lvl - lvl) ) { + fprintf (stderr, "Unable to create btree page\n"); + return bt_mgrclose (mgr), NULL; + } + } + +mgrlatch: +#ifdef unix + free (pagezero); +#else + VirtualFree (pagezero, 0, MEM_RELEASE); +#endif +#ifdef unix + // mlock the first segment of 64K pages + + flag = PROT_READ | PROT_WRITE; + mgr->pages[0] = mmap (0, (uid)65536 << mgr->page_bits, flag, MAP_SHARED, mgr->idx, 0); + mgr->segments = 1; + + if( mgr->pages[0] == MAP_FAILED ) { + fprintf (stderr, "Unable to mmap first btree segment, error = %d\n", errno); + return bt_mgrclose (mgr), NULL; + } + + mgr->pagezero = (BtPageZero *)mgr->pages[0]; + mlock (mgr->pagezero, mgr->page_size); + + mgr->redobuff = mgr->pages[0] + REDO_page * mgr->page_size; + mlock (mgr->redobuff, mgr->pagezero->redopages << mgr->page_bits); + + mgr->pagepool = mmap (0, (uid)mgr->nlatchpage << mgr->page_bits, flag, MAP_ANONYMOUS | MAP_SHARED, -1, 0); + if( mgr->pagepool == 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->pagepool = MapViewOfFile(mgr->pool, flag, 0, 0, size); + if( !mgr->pagepool ) { + fprintf (stderr, "Unable to map buffer pool, error = %d\n", GetLastError()); + return bt_mgrclose (mgr), NULL; + } +#endif + + mgr->latchsets = (BtLatchSet *)(mgr->pagepool + ((uid)mgr->latchtotal << mgr->page_bits)); + mgr->hashtable = (BtHashEntry *)(mgr->latchsets + mgr->latchtotal); + mgr->latchhash = (mgr->pagepool + ((uid)mgr->nlatchpage << mgr->page_bits) - (unsigned char *)mgr->hashtable) / sizeof(BtHashEntry); + + return mgr; +} + +// open BTree access method +// based on buffer manager + +BtDb *bt_open (BtMgr *mgr, BtMgr *main) +{ +BtDb *bt = malloc (sizeof(*bt)); + + memset (bt, 0, sizeof(*bt)); + bt->main = main; + bt->mgr = mgr; +#ifdef unix + bt->cursor = valloc (mgr->page_size); + bt->frame = valloc (mgr->page_size); +#else + bt->cursor = VirtualAlloc(NULL, mgr->page_size, MEM_COMMIT, PAGE_READWRITE); + bt->frame = VirtualAlloc(NULL, mgr->page_size, MEM_COMMIT, PAGE_READWRITE); +#endif +#ifdef unix + bt->thread_no = __sync_fetch_and_add (mgr->thread_no, 1) + 1; +#else + bt->thread_no = _InterlockedIncrement16(mgr->thread_no, 1); +#endif + return bt; +} + +// compare two keys, return > 0, = 0, or < 0 +// =0: keys are same +// -1: key2 > key1 +// +1: key2 < key1 +// 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 *latch, ushort thread_no) +{ + switch( mode ) { + case BtLockRead: + ReadLock (latch->readwr, thread_no); + break; + case BtLockWrite: + WriteLock (latch->readwr, thread_no); + break; + case BtLockAccess: + ReadLock (latch->access, thread_no); + break; + case BtLockDelete: + WriteLock (latch->access, thread_no); + break; + case BtLockParent: + WriteLock (latch->parent, thread_no); + break; + case BtLockAtomic: + WriteLock (latch->atomic, thread_no); + break; + case BtLockAtomic | BtLockRead: + WriteLock (latch->atomic, thread_no); + ReadLock (latch->readwr, thread_no); + break; + case BtLockAtomic | BtLockWrite: + WriteLock (latch->atomic, thread_no); + WriteLock (latch->readwr, thread_no); + break; + case BtLockLink: + WriteLock (latch->link, thread_no); + break; + } +} + +// remove write, read, or parent lock on requested page + +void bt_unlockpage(BtLock mode, BtLatchSet *latch) +{ + switch( mode ) { + case BtLockRead: + ReadRelease (latch->readwr); + break; + case BtLockWrite: + WriteRelease (latch->readwr); + break; + case BtLockAccess: + ReadRelease (latch->access); + break; + case BtLockDelete: + WriteRelease (latch->access); + break; + case BtLockParent: + WriteRelease (latch->parent); + break; + case BtLockAtomic: + WriteRelease (latch->atomic); + break; + case BtLockAtomic | BtLockRead: + WriteRelease (latch->atomic); + ReadRelease (latch->readwr); + break; + case BtLockAtomic | BtLockWrite: + WriteRelease (latch->atomic); + WriteRelease (latch->readwr); + break; + case BtLockLink: + WriteRelease (latch->link); + break; + } +} + +// allocate a new page +// return with page latched, but unlocked. + +int bt_newpage(BtMgr *mgr, BtPageSet *set, BtPage contents, ushort thread_id) +{ +uid page_no; +int blk; + + // lock allocation page + + bt_mutexlock(mgr->lock); + + // use empty chain first + // else allocate new page + + if( page_no = bt_getid(mgr->pagezero->freechain) ) { + if( set->latch = bt_pinlatch (mgr, page_no, NULL, thread_id) ) + set->page = bt_mappage (mgr, set->latch); + else + return mgr->line = __LINE__, mgr->err = BTERR_struct; + + mgr->pagezero->activepages++; + bt_putid(mgr->pagezero->freechain, bt_getid(set->page->right)); + + // the page is currently free and this + // will keep bt_txnpromote out. + + // contents will replace this bit + // and pin will keep bt_txnpromote out + + contents->page_no = page_no; + set->latch->dirty = 1; + + memcpy (set->page, contents, mgr->page_size); + +// if( msync (mgr->pagezero, mgr->page_size, MS_SYNC) < 0 ) +// fprintf(stderr, "msync error %d line %d\n", errno, __LINE__); + + bt_releasemutex(mgr->lock); + return 0; + } + + page_no = bt_getid(mgr->pagezero->alloc->right); + bt_putid(mgr->pagezero->alloc->right, page_no+1); + + // unlock allocation latch and + // extend file into new page. + + mgr->pagezero->activepages++; +// if( msync (mgr->pagezero, mgr->page_size, MS_SYNC) < 0 ) +// fprintf(stderr, "msync error %d line %d\n", errno, __LINE__); + bt_releasemutex(mgr->lock); + + // keep bt_txnpromote out of this page + + contents->free = 1; + contents->page_no = page_no; + pwrite (mgr->idx, contents, mgr->page_size, page_no << mgr->page_bits); + + // don't load cache from btree page, load it from contents + + if( set->latch = bt_pinlatch (mgr, page_no, contents, thread_id) ) + set->page = bt_mappage (mgr, set->latch); + else + return mgr->err; + + // now pin will keep bt_txnpromote out + + set->page->free = 0; + return 0; +} + +// find slot in page for given key at a given level + +int bt_findslot (BtPage page, unsigned char *key, uint len) +{ +uint diff, higher = page->cnt, low = 1, slot; +uint good = 0; + + // make stopper key an infinite fence value + + if( bt_getid (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(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 (BtMgr *mgr, BtPageSet *set, unsigned char *key, uint len, uint lvl, BtLock lock, ushort thread_no) +{ +uid page_no = ROOT_page, prevpage_no = 0; +uint drill = 0xff, slot; +BtLatchSet *prevlatch; +uint mode, prevmode; +BtPage prevpage; +BtVal *val; + + // 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 (mgr, page_no, NULL, thread_no)) ) + return 0; + + // obtain access lock using lock chaining with Access mode + + if( page_no > ROOT_page ) + bt_lockpage(BtLockAccess, set->latch, thread_no); + + set->page = bt_mappage (mgr, set->latch); + + // release & unpin parent or left sibling page + + if( prevpage_no ) { + bt_unlockpage(prevmode, prevlatch); + bt_unpinlatch (mgr, prevlatch); + prevpage_no = 0; + } + + // obtain mode lock using lock chaining through AccessLock + + bt_lockpage(mode, set->latch, thread_no); + + if( set->page->free ) + return mgr->err = BTERR_struct, mgr->line = __LINE__, 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->latch->page_no != ROOT_page ) + return mgr->err = BTERR_struct, mgr->line = __LINE__, 0; + + drill = set->page->lvl; + + if( lock != BtLockRead && drill == lvl ) { + bt_unlockpage(mode, set->latch); + bt_unpinlatch (mgr, set->latch); + continue; + } + } + + prevpage_no = set->latch->page_no; + prevlatch = set->latch; + prevpage = set->page; + prevmode = mode; + + // find key on page at this level + // and descend to requested level + + if( !set->page->kill ) + if( slot = bt_findslot (set->page, key, len) ) { + if( drill == lvl ) + return slot; + + // find next non-dead slot -- the fence key if nothing else + + while( slotptr(set->page, slot)->dead ) + if( slot++ < set->page->cnt ) + continue; + else + return mgr->err = BTERR_struct, mgr->line = __LINE__, 0; + + val = valptr(set->page, slot); + + if( val->len == BtId ) + page_no = bt_getid(valptr(set->page, slot)->value); + else + return mgr->line = __LINE__, mgr->err = BTERR_struct, 0; + + drill--; + continue; + } + + // slide right into next page + + page_no = bt_getid(set->page->right); + } while( page_no ); + + // return error on end of right chain + + mgr->line = __LINE__, mgr->err = BTERR_struct; + return 0; // return error +} + +// return page to free list +// page must be delete & write locked +// and have no keys pointing to it. + +void bt_freepage (BtMgr *mgr, BtPageSet *set) +{ + // lock allocation page + + bt_mutexlock (mgr->lock); + + // store chain + + memcpy(set->page->right, mgr->pagezero->freechain, BtId); + bt_putid(mgr->pagezero->freechain, set->latch->page_no); + set->latch->dirty = 1; + set->page->free = 1; + + // decrement active page count + + mgr->pagezero->activepages--; + +// if( msync (mgr->pagezero, mgr->page_size, MS_SYNC) < 0 ) +// fprintf(stderr, "msync error %d line %d\n", errno, __LINE__); + + // unlock released page + // and unlock allocation page + + bt_unlockpage (BtLockDelete, set->latch); + bt_unlockpage (BtLockWrite, set->latch); + bt_unpinlatch (mgr, set->latch); + bt_releasemutex (mgr->lock); +} + +// a fence key was deleted from a page +// push new fence value upwards + +BTERR bt_fixfence (BtMgr *mgr, BtPageSet *set, uint lvl, ushort thread_no) +{ +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, thread_no); + bt_unlockpage (BtLockWrite, set->latch); + + // insert new (now smaller) fence key + + bt_putid (value, set->latch->page_no); + ptr = (BtKey*)leftkey; + + if( bt_insertkey (mgr, ptr->key, ptr->len, lvl+1, value, BtId, Unique, thread_no) ) + return mgr->err; + + // now delete old fence key + + ptr = (BtKey*)rightkey; + + if( bt_deletekey (mgr, ptr->key, ptr->len, lvl+1, thread_no) ) + return mgr->err; + + bt_unlockpage (BtLockParent, set->latch); + bt_unpinlatch(mgr, set->latch); + return 0; +} + +// root has a single child +// collapse a level from the tree + +BTERR bt_collapseroot (BtMgr *mgr, BtPageSet *root, ushort thread_no) +{ +BtPageSet child[1]; +uid page_no; +BtVal *val; +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; + + val = valptr(root->page, idx); + + if( val->len == BtId ) + page_no = bt_getid (valptr(root->page, idx)->value); + else + return mgr->line = __LINE__, mgr->err = BTERR_struct; + + if( child->latch = bt_pinlatch (mgr, page_no, NULL, thread_no) ) + child->page = bt_mappage (mgr, child->latch); + else + return mgr->err; + + bt_lockpage (BtLockDelete, child->latch, thread_no); + bt_lockpage (BtLockWrite, child->latch, thread_no); + + memcpy (root->page, child->page, mgr->page_size); + root->latch->dirty = 1; + + bt_freepage (mgr, child); + + } while( root->page->lvl > 1 && root->page->act == 1 ); + + bt_unlockpage (BtLockWrite, root->latch); + bt_unpinlatch (mgr, root->latch); + return 0; +} + +// delete a page and manage keys +// call with page writelocked + +// returns the right page pool entry for freeing +// or zero on error. + +uint bt_deletepage (BtMgr *mgr, BtPageSet *set, ushort thread_no, BtLock mode) +{ +unsigned char lowerfence[BT_keyarray], higherfence[BT_keyarray]; +unsigned char value[BtId]; +uint lvl = set->page->lvl; +BtPageSet right[1]; +uid page_no; +BtKey *ptr; + + // cache copy of fence key + // to remove in parent + + ptr = keyptr(set->page, set->page->cnt); + memcpy (lowerfence, ptr, ptr->len + sizeof(BtKey)); + + // obtain lock on right page + + page_no = bt_getid(set->page->right); + + if( right->latch = bt_pinlatch (mgr, page_no, NULL, thread_no) ) + right->page = bt_mappage (mgr, right->latch); + else + return 0; + + bt_lockpage (mode, right->latch, thread_no); + + // cache copy of key to update + + ptr = keyptr(right->page, right->page->cnt); + memcpy (higherfence, ptr, ptr->len + sizeof(BtKey)); + + if( right->page->kill ) + return mgr->line = __LINE__, mgr->err = BTERR_struct; + + // pull contents of right peer into our empty page + + bt_lockpage (BtLockLink, set->latch, thread_no); + memcpy (right->page->left, set->page->left, BtId); + memcpy (set->page, right->page, mgr->page_size); + set->page->page_no = set->latch->page_no; + set->latch->dirty = 1; + bt_unlockpage (BtLockLink, set->latch); + + // mark right page deleted and point it to left page + // until we can post parent updates that remove access + // to the deleted page. + + bt_putid (right->page->right, set->latch->page_no); + right->latch->dirty = 1; + right->page->kill = 1; + + bt_lockpage (BtLockParent, right->latch, thread_no); + bt_unlockpage (mode, right->latch); + + bt_lockpage (BtLockParent, set->latch, thread_no); + bt_unlockpage (BtLockWrite, set->latch); + + // redirect higher key directly to our new node contents + + bt_putid (value, set->latch->page_no); + ptr = (BtKey*)higherfence; + + if( bt_insertkey (mgr, ptr->key, ptr->len, lvl+1, value, BtId, Unique, thread_no) ) + return 0; + + // delete old lower key to our node + + ptr = (BtKey*)lowerfence; + + if( bt_deletekey (mgr, ptr->key, ptr->len, lvl+1, thread_no) ) + return 0; + + bt_unlockpage (BtLockParent, set->latch); + return right->latch - mgr->latchsets; +} + +// find and delete key on page by marking delete flag bit +// if page becomes empty, delete it from the btree + +BTERR bt_deletekey (BtMgr *mgr, unsigned char *key, uint len, uint lvl, ushort thread_no) +{ +uint slot, idx, found, fence, entry; +BtPageSet set[1], right[1]; +BtSlot *node; +BtKey *ptr; +BtVal *val; + + if( slot = bt_loadpage (mgr, set, key, len, lvl, BtLockWrite, thread_no) ) { + node = slotptr(set->page, slot); + ptr = keyptr(set->page, slot); + } else + return mgr->err; + + // if librarian slot, advance to real slot + + if( node->type == Librarian ) { + ptr = keyptr(set->page, ++slot); + node = slotptr(set->page, slot); + } + + fence = slot == set->page->cnt; + + // delete the key, ignore request if already dead + + if( found = !keycmp (ptr, key, len) ) + if( found = node->dead == 0 ) { + val = valptr(set->page,slot); + set->page->garbage += ptr->len + val->len + sizeof(BtKey) + sizeof(BtVal); + set->page->act--; + + // mark node type as delete + + node->type = Delete; + node->dead = 1; + + // collapse empty slots beneath the fence + // on interiour nodes + + if( lvl ) + 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; + } + + if( !found ) + return 0; + + // did we delete a fence key in an upper level? + + if( lvl && set->page->act && fence ) + if( bt_fixfence (mgr, set, lvl, thread_no) ) + return mgr->err; + else + return 0; + + // do we need to collapse root? + + if( set->latch->page_no == ROOT_page && set->page->act == 1 ) + if( bt_collapseroot (mgr, set, thread_no) ) + return mgr->err; + else + return 0; + + // delete empty page + + if( !set->page->act ) { + if( entry = bt_deletepage (mgr, set, thread_no, BtLockWrite) ) + right->latch = mgr->latchsets + entry; + else + return mgr->err; + + // obtain delete and write locks to right node + + bt_unlockpage (BtLockParent, right->latch); + right->page = bt_mappage (mgr, right->latch); + bt_lockpage (BtLockDelete, right->latch, thread_no); + bt_lockpage (BtLockWrite, right->latch, thread_no); + bt_freepage (mgr, right); + + bt_unpinlatch (mgr, set->latch); + return 0; + } + + set->latch->dirty = 1; + bt_unlockpage(BtLockWrite, set->latch); + bt_unpinlatch (mgr, set->latch); + return 0; +} + +// 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->mgr, page_no, NULL, bt->thread_no) ) + set->page = bt_mappage (bt->mgr, set->latch); + else + return 0; + else + return bt->mgr->err = BTERR_struct, bt->mgr->line = __LINE__, 0; + + // obtain access lock using lock chaining with Access mode + + bt_lockpage(BtLockAccess, set->latch, bt->thread_no); + + bt_unlockpage(BtLockRead, prevlatch); + bt_unpinlatch (bt->mgr, prevlatch); + + bt_lockpage(BtLockRead, set->latch, bt->thread_no); + bt_unlockpage(BtLockAccess, set->latch); + return 1; +} + +// find unique key == given key, or first duplicate key in +// leaf level and return number of value bytes +// or (-1) if not found. + +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->mgr, set, key, keylen, 0, BtLockRead, bt->thread_no) ) + 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 (bt->mgr, 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(BtMgr *mgr, BtPageSet *set, uint keylen, uint slot, uint vallen) +{ +BtPage page = set->page, frame; +uint nxt = mgr->page_size; +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; + + frame = malloc (mgr->page_size); + memcpy (frame, page, mgr->page_size); + + // skip page info and set rest of page to zero + + memset (page+1, 0, 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 || frame->lvl ) + if( slotptr(frame,cnt)->dead ) + continue; + + // copy the value across + + val = valptr(frame, cnt); + nxt -= val->len + sizeof(BtVal); + memcpy ((unsigned char *)page + nxt, val, val->len + sizeof(BtVal)); + + // copy the key across + + key = keyptr(frame, cnt); + nxt -= key->len + sizeof(BtKey); + memcpy ((unsigned char *)page + nxt, key, key->len + sizeof(BtKey)); + + // make a librarian slot + + 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(frame, cnt)->type; + + if( !(slotptr(page, idx)->dead = slotptr(frame, cnt)->dead) ) + page->act++; + } + + page->min = nxt; + page->cnt = idx; + free (frame); + + // 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(BtMgr *mgr, BtPageSet *root, BtLatchSet *right, ushort page_no) +{ +unsigned char leftkey[BT_keyarray]; +uint nxt = mgr->page_size; +unsigned char value[BtId]; +BtPageSet left[1]; +uid left_page_no; +BtPage frame; +BtKey *ptr; +BtVal *val; + + frame = malloc (mgr->page_size); + memcpy (frame, root->page, mgr->page_size); + + // save left page fence key for new root + + ptr = keyptr(root->page, root->page->cnt); + memcpy (leftkey, ptr, ptr->len + sizeof(BtKey)); + + // Obtain an empty page to use, and copy the current + // root contents into it, e.g. lower keys + + if( bt_newpage(mgr, left, frame, page_no) ) + return mgr->err; + + left_page_no = left->latch->page_no; + bt_unpinlatch (mgr, left->latch); + free (frame); + + // preserve the page info at the bottom + // of higher keys and set rest to zero + + memset(root->page+1, 0, 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; + + ptr = (BtKey *)leftkey; + nxt -= ptr->len + sizeof(BtKey); + slotptr(root->page, 1)->off = nxt; + memcpy ((unsigned char *)root->page + nxt, leftkey, ptr->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++; + + mgr->pagezero->alloc->lvl = root->page->lvl; + + // release and unpin root pages + + bt_unlockpage(BtLockWrite, root->latch); + bt_unpinlatch (mgr, root->latch); + + bt_unpinlatch (mgr, right); + return 0; +} + +// split already locked full node +// leave it locked. +// return pool entry for new right +// page, pinned & unlocked + +uint bt_splitpage (BtMgr *mgr, BtPageSet *set, ushort thread_no) +{ +uint cnt = 0, idx = 0, max, nxt = mgr->page_size; +BtPage frame = malloc (mgr->page_size); +uint lvl = set->page->lvl; +BtPageSet right[1]; +BtKey *key, *ptr; +BtVal *val, *src; +uid right2; +uint prev; + + // split higher half of keys to frame + + memset (frame, 0, mgr->page_size); + max = set->page->cnt; + cnt = max / 2; + idx = 0; + + while( cnt++ < max ) { + if( cnt < max || set->page->lvl ) + if( slotptr(set->page, cnt)->dead ) + continue; + + src = valptr(set->page, cnt); + nxt -= src->len + sizeof(BtVal); + memcpy ((unsigned char *)frame + nxt, src, src->len + sizeof(BtVal)); + + key = keyptr(set->page, cnt); + nxt -= key->len + sizeof(BtKey); + ptr = (BtKey*)((unsigned char *)frame + nxt); + memcpy (ptr, key, key->len + sizeof(BtKey)); + + // add librarian slot + + slotptr(frame, ++idx)->off = nxt; + slotptr(frame, idx)->type = Librarian; + slotptr(frame, idx)->dead = 1; + + // add actual slot + + slotptr(frame, ++idx)->off = nxt; + slotptr(frame, idx)->type = slotptr(set->page, cnt)->type; + + if( !(slotptr(frame, idx)->dead = slotptr(set->page, cnt)->dead) ) + frame->act++; + } + + frame->bits = mgr->page_bits; + frame->min = nxt; + frame->cnt = idx; + frame->lvl = lvl; + + // link right node + + if( set->latch->page_no > ROOT_page ) + bt_putid (frame->right, bt_getid (set->page->right)); + + // get new free page and write higher keys to it. + + if( bt_newpage(mgr, right, frame, thread_no) ) + return 0; + + // process lower keys + + memcpy (frame, set->page, mgr->page_size); + memset (set->page+1, 0, mgr->page_size - sizeof(*set->page)); + set->latch->dirty = 1; + + nxt = mgr->page_size; + set->page->garbage = 0; + set->page->act = 0; + max /= 2; + cnt = 0; + idx = 0; + + if( slotptr(frame, max)->type == Librarian ) + max--; + + // assemble page of smaller keys + + while( cnt++ < max ) { + if( slotptr(frame, cnt)->dead ) + continue; + val = valptr(frame, cnt); + nxt -= val->len + sizeof(BtVal); + memcpy ((unsigned char *)set->page + nxt, val, val->len + sizeof(BtVal)); + + key = keyptr(frame, cnt); + nxt -= key->len + sizeof(BtKey); + memcpy ((unsigned char *)set->page + nxt, key, key->len + sizeof(BtKey)); + + // add librarian slot + + 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(frame, cnt)->type; + set->page->act++; + } + + bt_putid(set->page->right, right->latch->page_no); + set->page->min = nxt; + set->page->cnt = idx; + free(frame); + + return right->latch - mgr->latchsets; +} + +// fix keys for newly split page +// call with both pages pinned & locked +// return unlocked and unpinned + +BTERR bt_splitkeys (BtMgr *mgr, BtPageSet *set, BtLatchSet *right, ushort thread_no) +{ +unsigned char leftkey[BT_keyarray], rightkey[BT_keyarray]; +unsigned char value[BtId]; +uint lvl = set->page->lvl; +BtPage page; +BtKey *ptr; + + // if current page is the root page, split it + + if( set->latch->page_no == ROOT_page ) + return bt_splitroot (mgr, set, right, thread_no); + + ptr = keyptr(set->page, set->page->cnt); + memcpy (leftkey, ptr, ptr->len + sizeof(BtKey)); + + page = bt_mappage (mgr, right); + + ptr = keyptr(page, page->cnt); + memcpy (rightkey, ptr, ptr->len + sizeof(BtKey)); + + // insert new fences in their parent pages + + bt_lockpage (BtLockParent, right, thread_no); + + bt_lockpage (BtLockParent, set->latch, thread_no); + bt_unlockpage (BtLockWrite, set->latch); + + // insert new fence for reformulated left block of smaller keys + + bt_putid (value, set->latch->page_no); + ptr = (BtKey *)leftkey; + + if( bt_insertkey (mgr, ptr->key, ptr->len, lvl+1, value, BtId, Unique, thread_no) ) + return mgr->err; + + // switch fence for right block of larger keys to new right page + + bt_putid (value, right->page_no); + ptr = (BtKey *)rightkey; + + if( bt_insertkey (mgr, ptr->key, ptr->len, lvl+1, value, BtId, Unique, thread_no) ) + return mgr->err; + + bt_unlockpage (BtLockParent, set->latch); + bt_unpinlatch (mgr, set->latch); + + bt_unlockpage (BtLockParent, right); + bt_unpinlatch (mgr, right); + return 0; +} + +// install new key and value onto page +// page must already be checked for +// adequate space + +BTERR bt_insertslot (BtMgr *mgr, BtPageSet *set, uint slot, unsigned char *key,uint keylen, unsigned char *value, uint vallen, uint type, uint release) +{ +uint idx, librarian; +BtSlot *node; +BtKey *ptr; +BtVal *val; +int rate; + + // 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, + // adding as many librarian slots as + // makes sense. + + if( idx == set->page->cnt ) { + int avail = 4 * set->page->min / 5 - sizeof(*set->page) - ++set->page->cnt * sizeof(BtSlot); + + librarian = ++idx - slot; + avail /= sizeof(BtSlot); + + if( avail < 0 ) + avail = 0; + + if( librarian > avail ) + librarian = avail; + + if( librarian ) { + rate = (idx - slot) / librarian; + set->page->cnt += librarian; + idx += librarian; + } else + rate = 0; + } else + librarian = 0, rate = 0; + + while( idx > slot ) { + // transfer slot + *slotptr(set->page, idx) = *slotptr(set->page, idx-librarian-1); + idx--; + + // add librarian slot per rate + + if( librarian ) + if( (idx - slot + 1)/2 <= librarian * rate ) { + node = slotptr(set->page, idx--); + node->off = node[1].off; + node->type = Librarian; + node->dead = 1; + librarian--; + } + } + + set->latch->dirty = 1; + set->page->act++; + + // fill in new slot + + node = slotptr(set->page, slot); + node->off = set->page->min; + node->type = type; + node->dead = 0; + + if( release ) { + bt_unlockpage (BtLockWrite, set->latch); + bt_unpinlatch (mgr, 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 (BtMgr *mgr, unsigned char *key, uint keylen, uint lvl, void *value, uint vallen, BtSlotType type, ushort thread_no) +{ +uint slot, idx, len, entry; +BtPageSet set[1]; +BtSlot *node; +BtKey *ptr; +BtVal *val; + + while( 1 ) { // find the page and slot for the current key + if( slot = bt_loadpage (mgr, set, key, keylen, lvl, BtLockWrite, thread_no) ) { + node = slotptr(set->page, slot); + ptr = keyptr(set->page, slot); + } else { + if( !mgr->err ) + mgr->line = __LINE__, mgr->err = BTERR_ovflw; + return mgr->err; + } + + // if librarian slot == found slot, advance to real slot + + if( node->type == Librarian ) + if( !keycmp (ptr, key, keylen) ) { + ptr = keyptr(set->page, ++slot); + node = slotptr(set->page, slot); + } + + // if inserting a duplicate key or unique + // key that doesn't exist on the page, + // check for adequate space on the page + // and insert the new key before slot. + + switch( type ) { + case Unique: + case Duplicate: + if( keycmp (ptr, key, keylen) ) + if( slot = bt_cleanpage (mgr, set, keylen, slot, vallen) ) + return bt_insertslot (mgr, set, slot, key, keylen, value, vallen, type, 1); + else if( !(entry = bt_splitpage (mgr, set, thread_no)) ) + return mgr->err; + else if( bt_splitkeys (mgr, set, mgr->latchsets + entry, thread_no) ) + return mgr->err; + else + continue; + + // 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++; + node->type = type; + node->dead = 0; + + set->page->garbage += val->len - vallen; + set->latch->dirty = 1; + val->len = vallen; + memcpy (val->value, value, vallen); + bt_unlockpage(BtLockWrite, set->latch); + bt_unpinlatch (mgr, set->latch); + return 0; + } + + // new update value doesn't fit in existing value area + // make sure page has room + + if( !node->dead ) + set->page->garbage += val->len + ptr->len + sizeof(BtKey) + sizeof(BtVal); + else + set->page->act++; + + node->type = type; + node->dead = 0; + + if( !(slot = bt_cleanpage (mgr, set, keylen, slot, vallen)) ) + if( !(entry = bt_splitpage (mgr, set, thread_no)) ) + return mgr->err; + else if( bt_splitkeys (mgr, set, mgr->latchsets + entry, thread_no) ) + return mgr->err; + else + continue; + + // copy key and value onto page and update slot + + 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; + + node->off = set->page->min; + bt_unlockpage(BtLockWrite, set->latch); + bt_unpinlatch (mgr, set->latch); + return 0; + } + } + return 0; +} + +// determine actual page where key is located +// return slot number + +uint bt_atomicpage (BtMgr *mgr, BtPage source, AtomicTxn *locks, uint src, BtPageSet *set) +{ +BtKey *key = keyptr(source,src); +uint slot = locks[src].slot; +uint entry; + + if( src > 1 && locks[src].reuse ) + entry = locks[src-1].entry, slot = 0; + else + entry = locks[src].entry; + + if( slot ) { + set->latch = mgr->latchsets + entry; + set->page = bt_mappage (mgr, set->latch); + return slot; + } + + // is locks->reuse set? or was slot zeroed? + // if so, find where our key is located + // on current page or pages split on + // same page txn operations. + + do { + set->latch = mgr->latchsets + entry; + set->page = bt_mappage (mgr, set->latch); + + if( slot = bt_findslot(set->page, key->key, key->len) ) { + if( slotptr(set->page, slot)->type == Librarian ) + slot++; + if( locks[src].reuse ) + locks[src].entry = entry; + return slot; + } + } while( entry = set->latch->split ); + + mgr->line = __LINE__, mgr->err = BTERR_atomic; + return 0; +} + +BTERR bt_atomicinsert (BtMgr *mgr, BtPage source, AtomicTxn *locks, uint src, ushort thread_no, logseqno lsn) +{ +BtKey *key = keyptr(source, src); +BtVal *val = valptr(source, src); +BtLatchSet *latch; +BtPageSet set[1]; +uint entry, slot; + + while( slot = bt_atomicpage (mgr, source, locks, src, set) ) { + if( slot = bt_cleanpage(mgr, set, key->len, slot, val->len) ) { + if( bt_insertslot (mgr, set, slot, key->key, key->len, val->value, val->len, slotptr(source,src)->type, 0) ) + return mgr->err; + set->page->lsn = lsn; + return 0; + } + + // split page + + if( entry = bt_splitpage (mgr, set, thread_no) ) + latch = mgr->latchsets + entry; + else + return mgr->err; + + // splice right page into split chain + // and WriteLock it + + bt_lockpage(BtLockWrite, latch, thread_no); + latch->split = set->latch->split; + set->latch->split = entry; + locks[src].slot = 0; + } + + return mgr->line = __LINE__, mgr->err = BTERR_atomic; +} + +// perform delete from smaller btree +// insert a delete slot if not found there + +BTERR bt_atomicdelete (BtMgr *mgr, BtPage source, AtomicTxn *locks, uint src, ushort thread_no, logseqno lsn) +{ +BtKey *key = keyptr(source, src); +BtPageSet set[1]; +uint idx, slot; +BtSlot *node; +BtKey *ptr; +BtVal *val; + + if( slot = bt_atomicpage (mgr, source, locks, src, set) ) { + node = slotptr(set->page, slot); + ptr = keyptr(set->page, slot); + val = valptr(set->page, slot); + } else + return mgr->line = __LINE__, mgr->err = BTERR_struct; + + // if slot is not found, insert a delete slot + + if( keycmp (ptr, key->key, key->len) ) + return bt_insertslot (mgr, set, slot, key->key, key->len, NULL, 0, Delete, 0); + + // if node is already dead, + // ignore the request. + + if( node->dead ) + return 0; + + set->page->garbage += ptr->len + val->len + sizeof(BtKey) + sizeof(BtVal); + set->latch->dirty = 1; + set->page->lsn = lsn; + set->page->act--; + + node->dead = 0; + __sync_fetch_and_add(&mgr->found, 1); + return 0; +} + +int qsortcmp (BtSlot *slot1, BtSlot *slot2, BtPage page) +{ +BtKey *key1 = (BtKey *)((char *)page + slot1->off); +BtKey *key2 = (BtKey *)((char *)page + slot2->off); + + return keycmp (key1, key2->key, key2->len); +} +// atomic modification of a batch of keys. + +BTERR bt_atomictxn (BtDb *bt, BtPage source) +{ +uint src, idx, slot, samepage, entry, que = 0; +BtKey *key, *ptr, *key2; +int result = 0; +BtSlot temp[1]; +logseqno lsn; +int type; + + // stable sort the list of keys into order to + // prevent deadlocks between threads. +/* + for( src = 1; src++ < source->cnt; ) { + *temp = *slotptr(source,src); + key = keyptr (source,src); + + for( idx = src; --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; + } + } +*/ + qsort_r (slotptr(source,1), source->cnt, sizeof(BtSlot), (__compar_d_fn_t)qsortcmp, source); + // add entries to redo log + + if( bt->mgr->pagezero->redopages ) + lsn = bt_txnredo (bt->mgr, source, bt->thread_no); + else + lsn = 0; + + // perform the individual actions in the transaction + + if( bt_atomicexec (bt->mgr, source, lsn, 0, bt->thread_no) ) + return bt->mgr->err; + + // if number of active pages + // is greater than the buffer pool + // promote page into larger btree + + if( bt->main ) + while( bt->mgr->pagezero->activepages > bt->mgr->latchtotal - 10 ) + if( bt_txnpromote (bt) ) + return bt->mgr->err; + + // return success + + return 0; +} + +BTERR bt_atomicexec(BtMgr *mgr, BtPage source, logseqno lsn, int lsm, ushort thread_no) +{ +uint src, idx, slot, samepage, entry, que = 0; +BtPageSet set[1], prev[1], right[1]; +unsigned char value[BtId]; +uid right_page_no; +BtLatchSet *latch; +AtomicTxn *locks; +BtKey *key, *ptr; +BtPage page; +BtVal *val; + + locks = calloc (source->cnt + 1, sizeof(AtomicTxn)); + + // Load the leaf page for each key + // group same page references with reuse bit + // and determine any constraint violations + + for( src = 0; src++ < source->cnt; ) { + key = keyptr(source, src); + slot = 0; + + // first determine if this modification falls + // on the same page as the previous modification + // note that the far right leaf page is a special case + + if( samepage = src > 1 ) + if( samepage = !bt_getid(set->page->right) || keycmp (keyptr(set->page, set->page->cnt), key->key, key->len) >= 0 ) + slot = bt_findslot(set->page, key->key, key->len); + + if( !slot ) + if( slot = bt_loadpage(mgr, set, key->key, key->len, 0, BtLockAtomic + BtLockWrite, thread_no) ) + set->latch->split = 0; + else + return mgr->err; + + if( slotptr(set->page, slot)->type == Librarian ) + slot++; + + if( !samepage ) { + locks[src].entry = set->latch - mgr->latchsets; + locks[src].slot = slot; + locks[src].reuse = 0; + } else { + locks[src].entry = 0; + locks[src].slot = 0; + locks[src].reuse = 1; + } + + // capture current lsn for master page + + locks[src].reqlsn = set->page->lsn; + } + + // insert or delete each key + // process any splits or merges + // run through txn list backwards + + samepage = source->cnt + 1; + + for( src = source->cnt; src; src-- ) { + if( locks[src].reuse ) + continue; + + // perform the txn operations + // from smaller to larger on + // the same page + + for( idx = src; idx < samepage; idx++ ) + switch( slotptr(source,idx)->type ) { + case Delete: + if( bt_atomicdelete (mgr, source, locks, idx, thread_no, lsn) ) + return mgr->err; + break; + + case Duplicate: + case Unique: + if( bt_atomicinsert (mgr, source, locks, idx, thread_no, lsn) ) + return mgr->err; + break; + + default: + bt_atomicpage (mgr, source, locks, idx, set); + continue; + } + + // after the same page operations have finished, + // process master page for splits or deletion. + + latch = prev->latch = mgr->latchsets + locks[src].entry; + prev->page = bt_mappage (mgr, prev->latch); + samepage = src; + + // pick-up all splits from master page + // each one is already pinned & WriteLocked. + + if( entry = latch->split ) do { + set->latch = mgr->latchsets + entry; + set->page = bt_mappage (mgr, set->latch); + + // delete empty master page by undoing its split + // (this is potentially another empty page) + + if( !prev->page->act ) { + memcpy (set->page->left, prev->page->left, BtId); + memcpy (prev->page, set->page, mgr->page_size); + bt_lockpage (BtLockDelete, set->latch, thread_no); + prev->latch->split = set->latch->split; + prev->latch->dirty = 1; + bt_freepage (mgr, set); + continue; + } + + // remove empty split page from the split chain + // and return it to the free list. No other + // thread has its page number yet. + + if( !set->page->act ) { + memcpy (prev->page->right, set->page->right, BtId); + prev->latch->split = set->latch->split; + + bt_lockpage (BtLockDelete, set->latch, thread_no); + bt_freepage (mgr, set); + continue; + } + + // update prev's fence key + + ptr = keyptr(prev->page,prev->page->cnt); + bt_putid (value, prev->latch->page_no); + + if( bt_insertkey (mgr, ptr->key, ptr->len, 1, value, BtId, Unique, thread_no) ) + return mgr->err; + + // splice in the left link into the split page + + bt_putid (set->page->left, prev->latch->page_no); + + if( lsm ) + bt_syncpage (mgr, prev->page, prev->latch); + + // page is unlocked & unpinned below to avoid bt_txnpromote + + *prev = *set; + } while( entry = prev->latch->split ); + + // update left pointer in next right page from last split page + // (if all splits were reversed or none occurred, latch->split == 0) + + if( latch->split ) { + // fix left pointer in master's original (now split) + // far right sibling or set rightmost page in page zero + + if( right_page_no = bt_getid (prev->page->right) ) { + if( set->latch = bt_pinlatch (mgr, right_page_no, NULL, thread_no) ) + set->page = bt_mappage (mgr, set->latch); + else + return mgr->err; + + bt_lockpage (BtLockLink, set->latch, thread_no); + bt_putid (set->page->left, prev->latch->page_no); + set->latch->dirty = 1; + + bt_unlockpage (BtLockLink, set->latch); + bt_unpinlatch (mgr, set->latch); + } else { // prev is rightmost page + bt_mutexlock (mgr->lock); + bt_putid (mgr->pagezero->alloc->left, prev->latch->page_no); + bt_releasemutex(mgr->lock); + } + + // Process last page split in chain + // by switching the key from the master + // page to the last split. + + ptr = keyptr(prev->page,prev->page->cnt); + bt_putid (value, prev->latch->page_no); + + if( bt_insertkey (mgr, ptr->key, ptr->len, 1, value, BtId, Unique, thread_no) ) + return mgr->err; + + if( lsm ) + bt_syncpage (mgr, prev->page, prev->latch); + + // unlock and unpin master page + + bt_unlockpage(BtLockAtomic, latch); + bt_unlockpage(BtLockWrite, latch); + bt_unpinlatch(mgr, latch); + + // go through the list of splits and + // release the locks and unpin + + while( entry = latch->split ) { + latch = mgr->latchsets + entry; + bt_unlockpage(BtLockWrite, latch); + bt_unpinlatch(mgr, latch); + } + + continue; + } + + // since there are no splits, we're + // finished if master page occupied + + bt_unlockpage(BtLockAtomic, prev->latch); + + if( prev->page->act ) { + bt_unlockpage(BtLockWrite, prev->latch); + + if( lsm ) + bt_syncpage (mgr, prev->page, prev->latch); + + bt_unpinlatch(mgr, prev->latch); + continue; + } + + // any and all splits were reversed, and the + // master page located in prev is empty, delete it + + if( entry = bt_deletepage (mgr, prev, thread_no, BtLockWrite) ) + right->latch = mgr->latchsets + entry; + else + return mgr->err; + + // obtain delete and write locks to right node + + bt_unlockpage (BtLockParent, right->latch); + right->page = bt_mappage (mgr, right->latch); + bt_lockpage (BtLockDelete, right->latch, thread_no); + bt_lockpage (BtLockWrite, right->latch, thread_no); + bt_freepage (mgr, right); + + bt_unpinlatch (mgr, prev->latch); + } + + free (locks); + return 0; +} + +// promote a page into the larger btree + +BTERR bt_txnpromote (BtDb *bt) +{ +BtPageSet set[1], right[1]; +uint entry, slot, idx; +BtSlot *node; +BtKey *ptr; +BtVal *val; + + while( 1 ) { +#ifdef unix + entry = __sync_fetch_and_add(&bt->mgr->latchpromote, 1); +#else + entry = _InterlockedIncrement (&bt->mgr->latchpromote) - 1; +#endif + entry %= bt->mgr->latchtotal; + + if( !entry ) + continue; + + set->latch = bt->mgr->latchsets + entry; + + if( !bt_mutextry(set->latch->modify) ) + continue; + + // skip this entry if it is pinned + + if( set->latch->pin & ~CLOCK_bit ) { + bt_releasemutex(set->latch->modify); + continue; + } + + set->page = bt_mappage (bt->mgr, set->latch); + + // entry never used or has no right sibling + + if( !set->latch->page_no || !bt_getid (set->page->right) ) { + bt_releasemutex(set->latch->modify); + continue; + } + + // entry interiour node or being killed + + if( set->page->lvl || set->page->free || set->page->kill ) { + bt_releasemutex(set->latch->modify); + continue; + } + + // pin the page for our useage + + set->latch->pin++; + bt_releasemutex(set->latch->modify); + bt_lockpage (BtLockAtomic | BtLockWrite, set->latch, bt->thread_no); + memcpy (bt->frame, set->page, bt->mgr->page_size); + +if( !(set->latch->page_no % 100) ) +fprintf(stderr, "Promote page %d, %d keys\n", set->latch->page_no, set->page->act); + + if( entry = bt_deletepage (bt->mgr, set, bt->thread_no, BtLockAtomic | BtLockWrite) ) + right->latch = bt->mgr->latchsets + entry; + else + return bt->mgr->err; + + // obtain delete and write locks to right node + + bt_unlockpage (BtLockParent, right->latch); + right->page = bt_mappage (bt->mgr, right->latch); + + // release page with its new contents + + bt_unlockpage (BtLockAtomic, set->latch); + bt_unpinlatch (bt->mgr, set->latch); + + // transfer slots in our selected page to larger btree + + if( bt_atomicexec (bt->main, bt->frame, 0, bt->mgr->pagezero->redopages ? 1 : 0, bt->thread_no) ) + return bt->main->err; + + // free the page we took over + + bt_lockpage (BtLockDelete, right->latch, bt->thread_no); + bt_lockpage (BtLockWrite, right->latch, bt->thread_no); + bt_freepage (bt->mgr, right); + return 0; + } +} + +// 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]; + + if( set->latch = bt_pinlatch (bt->mgr, page_no, NULL, bt->thread_no) ) + set->page = bt_mappage (bt->mgr, set->latch); + else + return 0; + + bt_lockpage(BtLockRead, set->latch, bt->thread_no); + memcpy (bt->cursor, set->page, bt->mgr->page_size); + bt_unlockpage(BtLockRead, set->latch); + bt_unpinlatch (bt->mgr, set->latch); + return bt->cursor->cnt; +} + +// return previous slot on cursor page + +uint bt_prevkey (BtDb *bt, uint slot) +{ +uid cursor_page = bt->cursor->page_no; +uid ourright, next, us = cursor_page; +BtPageSet set[1]; + + if( --slot ) + return slot; + + ourright = bt_getid(bt->cursor->right); + +goleft: + if( !(next = bt_getid(bt->cursor->left)) ) + return 0; + +findourself: + cursor_page = next; + + if( set->latch = bt_pinlatch (bt->mgr, next, NULL, bt->thread_no) ) + set->page = bt_mappage (bt->mgr, set->latch); + else + return 0; + + bt_lockpage(BtLockRead, set->latch, bt->thread_no); + memcpy (bt->cursor, set->page, bt->mgr->page_size); + bt_unlockpage(BtLockRead, set->latch); + bt_unpinlatch (bt->mgr, set->latch); + + next = bt_getid (bt->cursor->right); + + if( bt->cursor->kill ) + goto findourself; + + if( next != us ) + if( next == ourright ) + goto goleft; + else + goto findourself; + + 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; + + if( set->latch = bt_pinlatch (bt->mgr, right, NULL, bt->thread_no) ) + set->page = bt_mappage (bt->mgr, set->latch); + else + return 0; + + bt_lockpage(BtLockRead, set->latch, bt->thread_no); + memcpy (bt->cursor, set->page, bt->mgr->page_size); + bt_unlockpage(BtLockRead, set->latch); + bt_unpinlatch (bt->mgr, set->latch); + slot = 0; + + } while( 1 ); + + return bt->mgr->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->mgr, set, key, len, 0, BtLockRead, bt->thread_no) ) + memcpy (bt->cursor, set->page, bt->mgr->page_size); + else + return 0; + + bt_unlockpage(BtLockRead, set->latch); + bt_unpinlatch (bt->mgr, set->latch); + return 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 entry = 0; + + while( ++entry < mgr->latchtotal ) { + latch = mgr->latchsets + entry; + + if( *latch->readwr->value ) + fprintf(stderr, "latchset %d wrtlocked for page %d\n", entry, latch->page_no); + + if( *latch->access->value ) + fprintf(stderr, "latchset %d accesslocked for page %d\n", entry, latch->page_no); + + if( *latch->parent->value ) + fprintf(stderr, "latchset %d parentlocked for page %d\n", entry, latch->page_no); + + if( *latch->atomic->value ) + fprintf(stderr, "latchset %d atomiclocked for page %d\n", entry, latch->page_no); + + if( *latch->modify->value ) + fprintf(stderr, "latchset %d modifylocked for page %d\n", entry, latch->page_no); + + if( latch->pin & ~CLOCK_bit ) + fprintf(stderr, "latchset %d pinned %d times for page %d\n", entry, latch->pin & ~CLOCK_bit, latch->page_no); + } +} + +typedef struct { + char idx; + char *type; + char *infile; + BtMgr *main; + BtMgr *mgr; + int num; +} 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, idx; +uid next, page_no = LEAF_page; // start on first page of leaves +int ch, len = 0, slot, type = 0; +unsigned char key[BT_maxkey]; +unsigned char txn[65536]; +ThreadArg *args = arg; +BtPage page, frame; +BtPageSet set[1]; +uint nxt = 65536; +BtKey *ptr; +BtVal *val; +BtDb *bt; +FILE *in; + + bt = bt_open (args->mgr, args->main); + page = (BtPage)txn; + + if( args->idx < strlen (args->type) ) + ch = args->type[args->idx]; + else + ch = args->type[strlen(args->type) - 1]; + + switch(ch | 0x20) + { + case 'd': + type = Delete; + + case 'p': + if( !type ) + type = Unique; + + if( args->num ) + if( type == Delete ) + fprintf(stderr, "started TXN pennysort delete for %s\n", args->infile); + else + fprintf(stderr, "started TXN pennysort insert for %s\n", args->infile); + else + if( type == Delete ) + fprintf(stderr, "started pennysort delete for %s\n", args->infile); + else + fprintf(stderr, "started pennysort insert for %s\n", args->infile); + + if( in = fopen (args->infile, "rb") ) + while( ch = getc(in), ch != EOF ) + if( ch == '\n' ) + { + line++; + + if( !args->num ) { + if( bt_insertkey (bt->mgr, key, 10, 0, key + 10, len - 10, Unique, bt->thread_no) ) + fprintf(stderr, "Error %d Line: %d source: %d\n", bt->mgr->err, bt->mgr->line, line), exit(0); + len = 0; + continue; + } + + nxt -= len - 10; + memcpy (txn + nxt, key + 10, len - 10); + nxt -= 1; + txn[nxt] = len - 10; + nxt -= 10; + memcpy (txn + nxt, key, 10); + nxt -= 1; + txn[nxt] = 10; + slotptr(page,++cnt)->off = nxt; + slotptr(page,cnt)->type = type; + len = 0; + + if( cnt < args->num ) + continue; + + page->cnt = cnt; + page->act = cnt; + page->min = nxt; + + if( bt_atomictxn (bt, page) ) + fprintf(stderr, "Error %d Line: %d source: %d\n", bt->mgr->err, bt->mgr->line, line), exit(0); + nxt = sizeof(txn); + cnt = 0; + + } + else if( len < BT_maxkey ) + key[len++] = ch; + fprintf(stderr, "finished %s for %d keys\n", args->infile, line); + break; + + case 'w': + fprintf(stderr, "started indexing for %s\n", args->infile); + if( in = fopen (args->infile, "r") ) + while( ch = getc(in), ch != EOF ) + if( ch == '\n' ) + { + line++; + + if( bt_insertkey (bt->mgr, key, len, 0, NULL, 0, Unique, bt->thread_no) ) + fprintf(stderr, "Error %d Line: %d source: %d\n", bt->mgr->err, bt->mgr->line, line), exit(0); + len = 0; + } + else if( len < BT_maxkey ) + key[len++] = ch; + fprintf(stderr, "finished %s for %d keys\n", args->infile, line); + 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->mgr->err ) + fprintf(stderr, "Error %d Syserr %d Line: %d source: %d\n", bt->mgr->err, errno, bt->mgr->line, line), exit(0); + len = 0; + } + else if( len < BT_maxkey ) + key[len++] = ch; + fprintf(stderr, "finished %s for %d keys, found %d\n", args->infile, line, found); + break; + + case 's': + fprintf(stderr, "started scanning\n"); + + do { + if( set->latch = bt_pinlatch (bt->mgr, page_no, NULL, bt->thread_no) ) + set->page = bt_mappage (bt->mgr, set->latch); + else + fprintf(stderr, "unable to obtain latch"), exit(1); + + bt_lockpage (BtLockRead, set->latch, bt->thread_no); + 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 (bt->mgr, set->latch); + } while( page_no = next ); + + fprintf(stderr, " Total keys read %d\n", cnt); + 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\n", cnt); + break; + + case 'c': +#ifdef unix + posix_fadvise( bt->mgr->idx, 0, 0, POSIX_FADV_SEQUENTIAL); +#endif + fprintf(stderr, "started counting\n"); + next = REDO_page + bt->mgr->pagezero->redopages; + + while( page_no < bt_getid(bt->mgr->pagezero->alloc->right) ) { + if( bt_readpage (bt->mgr, bt->cursor, page_no) ) + break; + + if( !bt->cursor->free && !bt->cursor->lvl ) + cnt += bt->cursor->act; + + bt->mgr->reads++; + page_no = next++; + } + + cnt--; // remove stopper key + fprintf(stderr, " Total keys counted %d\n", cnt); + 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 redopages = 0; +uint poolsize = 0; +uint mainpool = 0; +uint mainbits = 0; +float elapsed; +int num = 0; +char key[1]; +BtMgr *main; +BtMgr *mgr; +BtKey *ptr; + + if( argc < 3 ) { + fprintf (stderr, "Usage: %s idx_file main_file cmds [page_bits buffer_pool_size txn_size recovery_pages main_bits main_pool src_file1 src_file2 ... ]\n", argv[0]); + fprintf (stderr, " where idx_file is the name of the cache btree file\n"); + fprintf (stderr, " where main_file is the name of the main btree file\n"); + fprintf (stderr, " cmds is a string of (c)ount/(r)ev scan/(w)rite/(s)can/(d)elete/(f)ind/(p)ennysort, with one character command for each input src_file. Commands with no input file need a placeholder.\n"); + fprintf (stderr, " page_bits is the page size in bits for the cache btree\n"); + fprintf (stderr, " buffer_pool_size is the number of pages in buffer pool for the cache btree\n"); + fprintf (stderr, " txn_size = n to block transactions into n units, or zero for no transactions\n"); + fprintf (stderr, " recovery_pages = n to implement recovery buffer with n pages, or zero for no recovery buffer\n"); + fprintf (stderr, " main_bits is the page size of the main btree in bits\n"); + fprintf (stderr, " main_pool is the number of main pages in the main buffer pool\n"); + fprintf (stderr, " src_file1 thru src_filen are files of keys separated by newline\n"); + exit(0); + } + + start = getCpuTime(0); + + if( argc > 4 ) + bits = atoi(argv[4]); + + if( argc > 5 ) + poolsize = atoi(argv[5]); + + if( !poolsize ) + fprintf (stderr, "Warning: no mapped_pool\n"); + + if( argc > 6 ) + num = atoi(argv[6]); + + if( argc > 7 ) + redopages = atoi(argv[7]); + + if( redopages + REDO_page > 65535 ) + fprintf (stderr, "Warning: Recovery buffer too large\n"); + + if( argc > 8 ) + mainbits = atoi(argv[8]); + + if( argc > 9 ) + mainpool = atoi(argv[9]); + + cnt = argc - 10; +#ifdef unix + threads = malloc (cnt * sizeof(pthread_t)); +#else + threads = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, cnt * sizeof(HANDLE)); +#endif + args = malloc ((cnt + 1) * sizeof(ThreadArg)); + + mgr = bt_mgr (argv[1], bits, poolsize, redopages); + + if( !mgr ) { + fprintf(stderr, "Index Open Error %s\n", argv[1]); + exit (1); + } + + if( mainbits ) { + main = bt_mgr (argv[2], mainbits, mainpool, 0); + + if( !main ) { + fprintf(stderr, "Index Open Error %s\n", argv[2]); + exit (1); + } + } else + main = NULL; + + // fire off threads + + if( cnt ) + for( idx = 0; idx < cnt; idx++ ) { + args[idx].infile = argv[idx + 10]; + args[idx].type = argv[3]; + args[idx].main = main; + args[idx].mgr = mgr; + args[idx].num = num; + 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, 131072, index_file, args + idx, 0, NULL); +#endif + } + else { + args[0].infile = argv[idx + 10]; + args[0].type = argv[3]; + args[0].main = main; + args[0].mgr = mgr; + args[0].num = num; + args[0].idx = 0; + index_file (args); + } + + // 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); + + if( main ) + bt_poolaudit(main); + + fprintf(stderr, "%d reads %d writes %d found\n", mgr->reads, mgr->writes, mgr->found); + + if( main ) + bt_mgrclose (main); + 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