From: unknown Date: Mon, 3 Feb 2014 16:28:41 +0000 (-0800) Subject: Latest btree fixes to bt_deletekey X-Git-Url: https://pd.if.org/git/?p=btree;a=commitdiff_plain;h=9483902b7056903984ab9670f5bac1337ad8f969 Latest btree fixes to bt_deletekey --- diff --git a/btree2s.c b/btree2s.c new file mode 100644 index 0000000..d34d938 --- /dev/null +++ b/btree2s.c @@ -0,0 +1,1821 @@ +// btree version 2s +// 02 FEB 2014 + +// author: karl malbrain, malbrain@cal.berkeley.edu + +/* +This work, including the source code, documentation +and related data, is placed into the public domain. + +The orginal author is Karl Malbrain. + +THIS SOFTWARE IS PROVIDED AS-IS WITHOUT WARRANTY +OF ANY KIND, NOT EVEN THE IMPLIED WARRANTY OF +MERCHANTABILITY. THE AUTHOR OF THIS SOFTWARE, +ASSUMES _NO_ RESPONSIBILITY FOR ANY CONSEQUENCE +RESULTING FROM THE USE, MODIFICATION, OR +REDISTRIBUTION OF THIS SOFTWARE. +*/ + +// Please see the project home page for documentation +// code.google.com/p/high-concurrency-btree + +#define _FILE_OFFSET_BITS 64 +#define _LARGEFILE64_SOURCE + +#ifdef linux +#define _GNU_SOURCE +#endif + +#ifdef unix +#include +#include +#include +#include +#include +#include +#include +#else +#define WIN32_LEAN_AND_MEAN +#include +#include +#include +#include +#include +#endif + +#include +#include + +typedef unsigned long long uid; + +#ifndef unix +typedef unsigned long long off64_t; +typedef unsigned short ushort; +typedef unsigned int uint; +#endif + +#define BT_ro 0x6f72 // ro +#define BT_rw 0x7772 // rw +#define BT_fl 0x6c66 // fl + +#define BT_maxbits 24 // maximum page size in bits +#define BT_minbits 9 // minimum page size in bits +#define BT_minpage (1 << BT_minbits) // minimum page size + +/* +There are five lock types for each node in three independent sets: +1. (set 1) AccessIntent: Sharable. Going to Read the node. Incompatible with NodeDelete. +2. (set 1) NodeDelete: Exclusive. About to release the node. Incompatible with AccessIntent. +3. (set 2) ReadLock: Sharable. Read the node. Incompatible with WriteLock. +4. (set 2) WriteLock: Exclusive. Modify the node. Incompatible with ReadLock and other WriteLocks. +5. (set 3) ParentModification: Exclusive. Change the node's parent keys. Incompatible with another ParentModification. +*/ + +typedef enum{ + BtLockAccess, + BtLockDelete, + BtLockRead, + BtLockWrite, + BtLockParent +}BtLock; + +// Define the length of the page and key pointers + +#define BtId 6 + +// Page key slot definition. + +// If BT_maxbits is 15 or less, you can save 2 bytes +// for each key stored by making the first two uints +// into ushorts. You can also save 4 bytes by removing +// the tod field from the key. + +// Keys are marked dead, but remain on the page until +// cleanup is called. The fence key (highest key) for +// the page is always present, even if dead. + +typedef struct { + uint off:BT_maxbits; // page offset for key start + uint dead:1; // set for deleted key + uint tod; // time-stamp for key + unsigned char id[BtId]; // id associated with key +} BtSlot; + +// The key structure occupies space at the upper end of +// each page. It's a length byte followed by the value +// bytes. + +typedef struct { + unsigned char len; + unsigned char key[0]; +} *BtKey; + +// The first part of an index page. +// It is immediately followed +// by the BtSlot array of keys. + +typedef struct { + uint cnt; // count of keys in page + uint act; // count of active keys + uint min; // next key offset + unsigned char bits; // page size in bits + unsigned char lvl:7; // level of page + unsigned char dirty:1; // page is dirty + unsigned char right[BtId]; // page number to right +} *BtPage; + +// The memory mapping hash table entry + +typedef struct { + BtPage page; // mapped page pointer + uid page_no; // mapped page number + void *lruprev; // least recently used previous cache block + void *lrunext; // lru next cache block + void *hashprev; // previous cache block for the same hash idx + void *hashnext; // next cache block for the same hash idx +#ifndef unix + HANDLE hmap; +#endif +}BtHash; + +// The object structure for Btree access + +typedef struct _BtDb { + uint page_size; // each page size + uint page_bits; // each page size in bits + uint seg_bits; // segment size in pages in bits + uid page_no; // current page number + uid cursor_page; // current cursor page number + int err; + uint mode; // read-write mode + uint mapped_io; // use memory mapping + BtPage temp; // temporary frame buffer (memory mapped/file IO) + BtPage alloc; // frame buffer for alloc page ( page 0 ) + BtPage cursor; // cached frame for start/next (never mapped) + BtPage frame; // spare frame for the page split (never mapped) + BtPage zero; // zeroes frame buffer (never mapped) + BtPage page; // current page +#ifdef unix + int idx; +#else + HANDLE idx; +#endif + unsigned char *mem; // frame, cursor, page memory buffer + int nodecnt; // highest page cache segment in use + int nodemax; // highest page cache segment allocated + int hashmask; // number of pages in segments - 1 + int hashsize; // size of hash table + BtHash *lrufirst; // lru list head + BtHash *lrulast; // lru list tail + ushort *cache; // hash table for cached segments + BtHash nodes[1]; // segment cache follows + int posted; // last loadpage found posted key + int found; // last deletekey found key + int fence; // last load page used fence position +} BtDb; + +typedef enum { +BTERR_ok = 0, +BTERR_struct, +BTERR_ovflw, +BTERR_lock, +BTERR_map, +BTERR_wrt, +BTERR_hash +} BTERR; + +// B-Tree functions +extern void bt_close (BtDb *bt); +extern BtDb *bt_open (char *name, uint mode, uint bits, uint cacheblk, uint pgblk); +extern BTERR bt_insertkey (BtDb *bt, unsigned char *key, uint len, uint lvl, uid id, uint tod); +extern BTERR bt_deletekey (BtDb *bt, unsigned char *key, uint len, uint lvl); +extern uid bt_findkey (BtDb *bt, unsigned char *key, uint len); +extern uint bt_startkey (BtDb *bt, unsigned char *key, uint len); +extern uint bt_nextkey (BtDb *bt, uint slot); + +// Helper functions to return slot values + +extern BtKey bt_key (BtDb *bt, uint slot); +extern uid bt_uid (BtDb *bt, uint slot); +extern uint bt_tod (BtDb *bt, uint slot); + +// BTree page number constants +#define ALLOC_page 0 +#define ROOT_page 1 +#define LEAF_page 2 + +// Number of levels to create in a new BTree + +#define MIN_lvl 2 + +// The page is allocated from low and hi ends. +// The key offsets and row-id's are allocated +// from the bottom, while the text of the key +// is 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 - 65534), and up to 253 bytes +// of key value. Duplicate keys are discarded. +// Associated with each key is a 48 bit row-id. + +// 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 right +// 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 node is always +// present, even after deletion and cleanup. + +// Deleted leaf pages are reclaimed on a free list. +// The upper levels of the btree are fixed on creation. + +// Groups of pages from the btree are optionally +// cached with memory mapping. A hash table is used to keep +// track of the cached pages. This behaviour is controlled +// by the number of cache blocks parameter and pages per block +// given to bt_open. + +// 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 (ALLOC page) is dedicated to lock for new page extensions, +// and chains empty leaf pages together for reuse. + +// Parent locks are obtained to prevent resplitting or deleting a node +// before its fence is posted into its upper level. + +// A special open mode of BT_fl is provided to safely access files on +// WIN32 networks. WIN32 network operations should not use memory mapping. +// This WIN32 mode sets FILE_FLAG_NOBUFFERING and FILE_FLAG_WRITETHROUGH +// to prevent local caching of network file contents. + +// 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)) + +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; +} + +// place write, read, or parent lock on requested page_no. + +BTERR bt_lockpage(BtDb *bt, uid page_no, BtLock mode) +{ +off64_t off = page_no << bt->page_bits; +#ifdef unix +int flag = PROT_READ | ( bt->mode == BT_ro ? 0 : PROT_WRITE ); +struct flock lock[1]; +#else +uint flags = 0, len; +OVERLAPPED ovl[1]; +#endif + + if( mode == BtLockRead || mode == BtLockWrite ) + off += sizeof(*bt->page); // use second segment + + if( mode == BtLockParent ) + off += 2 * sizeof(*bt->page); // use third segment + +#ifdef unix + memset (lock, 0, sizeof(lock)); + + lock->l_start = off; + lock->l_type = (mode == BtLockDelete || mode == BtLockWrite || mode == BtLockParent) ? F_WRLCK : F_RDLCK; + lock->l_len = sizeof(*bt->page); + lock->l_whence = 0; + + if( fcntl (bt->idx, F_SETLKW, lock) < 0 ) + return bt->err = BTERR_lock; + + return 0; +#else + memset (ovl, 0, sizeof(ovl)); + ovl->OffsetHigh = (uint)(off >> 32); + ovl->Offset = (uint)off; + len = sizeof(*bt->page); + + // use large offsets to + // simulate advisory locking + + ovl->OffsetHigh |= 0x80000000; + + if( mode == BtLockDelete || mode == BtLockWrite || mode == BtLockParent ) + flags |= LOCKFILE_EXCLUSIVE_LOCK; + + if( LockFileEx (bt->idx, flags, 0, len, 0L, ovl) ) + return bt->err = 0; + + return bt->err = BTERR_lock; +#endif +} + +// remove write, read, or parent lock on requested page_no. + +BTERR bt_unlockpage(BtDb *bt, uid page_no, BtLock mode) +{ +off64_t off = page_no << bt->page_bits; +#ifdef unix +struct flock lock[1]; +#else +OVERLAPPED ovl[1]; +uint len; +#endif + + if( mode == BtLockRead || mode == BtLockWrite ) + off += sizeof(*bt->page); // use second segment + + if( mode == BtLockParent ) + off += 2 * sizeof(*bt->page); // use third segment + +#ifdef unix + memset (lock, 0, sizeof(lock)); + + lock->l_start = off; + lock->l_type = F_UNLCK; + lock->l_len = sizeof(*bt->page); + lock->l_whence = 0; + + if( fcntl (bt->idx, F_SETLK, lock) < 0 ) + return bt->err = BTERR_lock; +#else + memset (ovl, 0, sizeof(ovl)); + ovl->OffsetHigh = (uint)(off >> 32); + ovl->Offset = (uint)off; + len = sizeof(*bt->page); + + // use large offsets to + // simulate advisory locking + + ovl->OffsetHigh |= 0x80000000; + + if( !UnlockFileEx (bt->idx, 0, len, 0, ovl) ) + return GetLastError(), bt->err = BTERR_lock; +#endif + + return bt->err = 0; +} + +// close and release memory + +void bt_close (BtDb *bt) +{ +BtHash *hash; +#ifdef unix + // release mapped pages + + if( hash = bt->lrufirst ) + do munmap (hash->page, (bt->hashmask+1) << bt->page_bits); + while(hash = hash->lrunext); + + if ( bt->mem ) + free (bt->mem); + close (bt->idx); + free (bt->cache); + free (bt); +#else + if( hash = bt->lrufirst ) + do + { + FlushViewOfFile(hash->page, 0); + UnmapViewOfFile(hash->page); + CloseHandle(hash->hmap); + } while(hash = hash->lrunext); + + if ( bt->mem) + VirtualFree (bt->mem, 0, MEM_RELEASE); + FlushFileBuffers(bt->idx); + CloseHandle(bt->idx); + GlobalFree (bt->cache); + GlobalFree (bt); +#endif +} + +// open/create new btree +// call with file_name, BT_openmode, bits in page size (e.g. 16), +// size of mapped page cache (e.g. 8192) or zero for no mapping. + +BtDb *bt_open (char *name, uint mode, uint bits, uint nodemax, uint pgblk) +{ +uint lvl, attr, cacheblk, last; +BtLock lockmode = BtLockWrite; +BtPage alloc; +off64_t size; +uint amt[1]; +BtKey key; +BtDb* bt; + +#ifndef unix +SYSTEM_INFO sysinfo[1]; +#endif + +#ifdef unix + bt = malloc (sizeof(BtDb) + nodemax * sizeof(BtHash)); + memset (bt, 0, sizeof(BtDb)); + + switch (mode & 0x7fff) + { + case BT_fl: + case BT_rw: + bt->idx = open ((char*)name, O_RDWR | O_CREAT, 0666); + break; + + case BT_ro: + default: + bt->idx = open ((char*)name, O_RDONLY); + lockmode = BtLockRead; + break; + } + if( bt->idx == -1 ) + return free(bt), NULL; + + if( nodemax ) + cacheblk = 4096; // page size for unix + else + cacheblk = 0; + +#else + bt = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, sizeof(BtDb) + nodemax * sizeof(BtHash)); + attr = FILE_ATTRIBUTE_NORMAL; + switch (mode & 0x7fff) + { + case BT_fl: + attr |= FILE_FLAG_WRITE_THROUGH | FILE_FLAG_NO_BUFFERING; + + case BT_rw: + bt->idx = CreateFile(name, GENERIC_READ| GENERIC_WRITE, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, attr, NULL); + break; + + case BT_ro: + default: + bt->idx = CreateFile(name, GENERIC_READ, FILE_SHARE_READ|FILE_SHARE_WRITE, NULL, OPEN_EXISTING, attr, NULL); + lockmode = BtLockRead; + break; + } + if( bt->idx == INVALID_HANDLE_VALUE ) + return GlobalFree(bt), NULL; + + // normalize cacheblk to multiple of sysinfo->dwAllocationGranularity + GetSystemInfo(sysinfo); + + if( nodemax ) + cacheblk = sysinfo->dwAllocationGranularity; + else + cacheblk = 0; +#endif + + // determine sanity of page size + + if( bits > BT_maxbits ) + bits = BT_maxbits; + else if( bits < BT_minbits ) + bits = BT_minbits; + + if ( bt_lockpage(bt, ALLOC_page, lockmode) ) + return bt_close (bt), NULL; + +#ifdef unix + *amt = 0; + + // read minimum page size to get root info + + if( size = lseek (bt->idx, 0L, 2) ) { + alloc = malloc (BT_minpage); + pread(bt->idx, alloc, BT_minpage, 0); + bits = alloc->bits; + free (alloc); + } else if( mode == BT_ro ) + return bt_close (bt), NULL; +#else + size = GetFileSize(bt->idx, amt); + + if( size || *amt ) { + alloc = VirtualAlloc(NULL, BT_minpage, MEM_COMMIT, PAGE_READWRITE); + if( !ReadFile(bt->idx, (char *)alloc, BT_minpage, amt, NULL) ) + return bt_close (bt), NULL; + bits = alloc->bits; + VirtualFree (alloc, 0, MEM_RELEASE); + } else if( mode == BT_ro ) + return bt_close (bt), NULL; +#endif + + bt->page_size = 1 << bits; + bt->page_bits = bits; + + bt->nodemax = nodemax; + bt->mode = mode; + + // setup cache mapping + + if( cacheblk ) { + if( cacheblk < bt->page_size ) + cacheblk = bt->page_size; + + bt->hashsize = nodemax / 8; + bt->hashmask = (cacheblk >> bits) - 1; + bt->mapped_io = 1; + } + + // requested number of pages per memmap segment + + if( cacheblk ) + if( (1 << pgblk) > bt->hashmask ) + bt->hashmask = (1 << pgblk) - 1; + + bt->seg_bits = 0; + + while( (1 << bt->seg_bits) <= bt->hashmask ) + bt->seg_bits++; + +#ifdef unix + bt->mem = malloc (6 *bt->page_size); + bt->cache = calloc (bt->hashsize, sizeof(ushort)); +#else + bt->mem = VirtualAlloc(NULL, 6 * bt->page_size, MEM_COMMIT, PAGE_READWRITE); + bt->cache = GlobalAlloc (GMEM_FIXED|GMEM_ZEROINIT, bt->hashsize * sizeof(ushort)); +#endif + bt->frame = (BtPage)bt->mem; + bt->cursor = (BtPage)(bt->mem + bt->page_size); + bt->page = (BtPage)(bt->mem + 2 * bt->page_size); + bt->alloc = (BtPage)(bt->mem + 3 * bt->page_size); + bt->temp = (BtPage)(bt->mem + 4 * bt->page_size); + bt->zero = (BtPage)(bt->mem + 5 * bt->page_size); + + if( size || *amt ) { + if ( bt_unlockpage(bt, ALLOC_page, lockmode) ) + return bt_close (bt), NULL; + + return bt; + } + + // initializes an empty b-tree with root page and page of leaves + + memset (bt->alloc, 0, bt->page_size); + bt_putid(bt->alloc->right, MIN_lvl+1); + bt->alloc->bits = bt->page_bits; + +#ifdef unix + if( write (bt->idx, bt->alloc, bt->page_size) < bt->page_size ) + return bt_close (bt), NULL; +#else + if( !WriteFile (bt->idx, (char *)bt->alloc, bt->page_size, amt, NULL) ) + return bt_close (bt), NULL; + + if( *amt < bt->page_size ) + return bt_close (bt), NULL; +#endif + + memset (bt->frame, 0, bt->page_size); + bt->frame->bits = bt->page_bits; + + for( lvl=MIN_lvl; lvl--; ) { + slotptr(bt->frame, 1)->off = bt->page_size - 3; + bt_putid(slotptr(bt->frame, 1)->id, lvl ? MIN_lvl - lvl + 1 : 0); // next(lower) page number + key = keyptr(bt->frame, 1); + key->len = 2; // create stopper key + key->key[0] = 0xff; + key->key[1] = 0xff; + bt->frame->min = bt->page_size - 3; + bt->frame->lvl = lvl; + bt->frame->cnt = 1; + bt->frame->act = 1; +#ifdef unix + if( write (bt->idx, bt->frame, bt->page_size) < bt->page_size ) + return bt_close (bt), NULL; +#else + if( !WriteFile (bt->idx, (char *)bt->frame, bt->page_size, amt, NULL) ) + return bt_close (bt), NULL; + + if( *amt < bt->page_size ) + return bt_close (bt), NULL; +#endif + } + + // create empty page area by writing last page of first + // cache area (other pages are zeroed by O/S) + + if( bt->mapped_io && bt->hashmask ) { + memset(bt->frame, 0, bt->page_size); + last = bt->hashmask; + + while( last < MIN_lvl + 1 ) + last += bt->hashmask + 1; +#ifdef unix + pwrite(bt->idx, bt->frame, bt->page_size, last << bt->page_bits); +#else + SetFilePointer (bt->idx, last << bt->page_bits, NULL, FILE_BEGIN); + if( !WriteFile (bt->idx, (char *)bt->frame, bt->page_size, amt, NULL) ) + return bt_close (bt), NULL; + if( *amt < bt->page_size ) + return bt_close (bt), NULL; +#endif + } + + if( bt_unlockpage(bt, ALLOC_page, lockmode) ) + return bt_close (bt), NULL; + + return bt; +} + +// compare two keys, returning > 0, = 0, or < 0 +// as the comparison value + +int keycmp (BtKey key1, unsigned char *key2, uint len2) +{ +uint len1 = key1->len; +int ans; + + if( ans = memcmp (key1->key, key2, len1 > len2 ? len2 : len1) ) + return ans; + + if( len1 > len2 ) + return 1; + if( len1 < len2 ) + return -1; + + return 0; +} + +// Update current page of btree by writing file contents +// or flushing mapped area to disk. + +BTERR bt_update (BtDb *bt, BtPage page, uid page_no) +{ +off64_t off = page_no << bt->page_bits; + +#ifdef unix + if ( !bt->mapped_io ) + if ( pwrite(bt->idx, page, bt->page_size, off) != bt->page_size ) + return bt->err = BTERR_wrt; +#else +uint amt[1]; + if ( !bt->mapped_io ) + { + SetFilePointer (bt->idx, (long)off, (long*)(&off)+1, FILE_BEGIN); + if( !WriteFile (bt->idx, (char *)page, bt->page_size, amt, NULL) ) + return GetLastError(), bt->err = BTERR_wrt; + + if( *amt < bt->page_size ) + return GetLastError(), bt->err = BTERR_wrt; + } + else if ( bt->mode == BT_fl ) { + FlushViewOfFile(page, bt->page_size); + FlushFileBuffers(bt->idx); + } +#endif + return 0; +} + +// find page in cache + +BtHash *bt_findhash(BtDb *bt, uid page_no) +{ +BtHash *hash; +uint idx; + + // compute cache block first page and hash idx + + page_no &= ~bt->hashmask; + idx = (uint)(page_no >> bt->seg_bits) % bt->hashsize; + + if( bt->cache[idx] ) + hash = bt->nodes + bt->cache[idx]; + else + return NULL; + + do if( hash->page_no == page_no ) + break; + while(hash = hash->hashnext ); + + return hash; +} + +// add page cache entry to hash index + +void bt_linkhash(BtDb *bt, BtHash *node, uid page_no) +{ +uint idx = (uint)(page_no >> bt->seg_bits) % bt->hashsize; +BtHash *hash; + + if( bt->cache[idx] ) { + node->hashnext = hash = bt->nodes + bt->cache[idx]; + hash->hashprev = node; + } + + node->hashprev = NULL; + bt->cache[idx] = (ushort)(node - bt->nodes); +} + +// remove cache entry from hash table + +void bt_unlinkhash(BtDb *bt, BtHash *node) +{ +uint idx = (uint)(node->page_no >> bt->seg_bits) % bt->hashsize; +BtHash *hash; + + // unlink node + if( hash = node->hashprev ) + hash->hashnext = node->hashnext; + else if( hash = node->hashnext ) + bt->cache[idx] = (ushort)(hash - bt->nodes); + else + bt->cache[idx] = 0; + + if( hash = node->hashnext ) + hash->hashprev = node->hashprev; +} + +// add cache page to lru chain and map pages + +BtPage bt_linklru(BtDb *bt, BtHash *hash, uid page_no) +{ +int flag; +off64_t off = (page_no & ~bt->hashmask) << bt->page_bits; +off64_t limit = off + ((bt->hashmask+1) << bt->page_bits); +BtHash *node; + + memset(hash, 0, sizeof(BtHash)); + hash->page_no = (page_no & ~bt->hashmask); + bt_linkhash(bt, hash, page_no); + + if( node = hash->lrunext = bt->lrufirst ) + node->lruprev = hash; + else + bt->lrulast = hash; + + bt->lrufirst = hash; + +#ifdef unix + flag = PROT_READ | ( bt->mode == BT_ro ? 0 : PROT_WRITE ); + hash->page = (BtPage)mmap (0, (bt->hashmask+1) << bt->page_bits, flag, MAP_SHARED, bt->idx, off); + if( hash->page == MAP_FAILED ) + return bt->err = BTERR_map, (BtPage)NULL; + +#else + flag = ( bt->mode == BT_ro ? PAGE_READONLY : PAGE_READWRITE ); + hash->hmap = CreateFileMapping(bt->idx, NULL, flag, (DWORD)(limit >> 32), (DWORD)limit, NULL); + if( !hash->hmap ) + return bt->err = BTERR_map, NULL; + + flag = ( bt->mode == BT_ro ? FILE_MAP_READ : FILE_MAP_WRITE ); + hash->page = MapViewOfFile(hash->hmap, flag, (DWORD)(off >> 32), (DWORD)off, (bt->hashmask+1) << bt->page_bits); + if( !hash->page ) + return bt->err = BTERR_map, NULL; +#endif + + return (BtPage)((char*)hash->page + ((uint)(page_no & bt->hashmask) << bt->page_bits)); +} + +// find or place requested page in page-cache +// return memory address where page is located. + +BtPage bt_hashpage(BtDb *bt, uid page_no) +{ +BtHash *hash, *node, *next; +BtPage page; + + // find page in cache and move to top of lru list + + if( hash = bt_findhash(bt, page_no) ) { + page = (BtPage)((char*)hash->page + ((uint)(page_no & bt->hashmask) << bt->page_bits)); + // swap node in lru list + if( node = hash->lruprev ) { + if( next = node->lrunext = hash->lrunext ) + next->lruprev = node; + else + bt->lrulast = node; + + if( next = hash->lrunext = bt->lrufirst ) + next->lruprev = hash; + else + return bt->err = BTERR_hash, (BtPage)NULL; + + hash->lruprev = NULL; + bt->lrufirst = hash; + } + return page; + } + + // map pages and add to cache entry + + if( bt->nodecnt < bt->nodemax ) { + hash = bt->nodes + ++bt->nodecnt; + return bt_linklru(bt, hash, page_no); + } + + // hash table is already full, replace last lru entry from the cache + + if( hash = bt->lrulast ) { + // unlink from lru list + if( node = bt->lrulast = hash->lruprev ) + node->lrunext = NULL; + else + return bt->err = BTERR_hash, (BtPage)NULL; + +#ifdef unix + munmap (hash->page, (bt->hashmask+1) << bt->page_bits); +#else + FlushViewOfFile(hash->page, 0); + UnmapViewOfFile(hash->page); + CloseHandle(hash->hmap); +#endif + // unlink from hash table + + bt_unlinkhash(bt, hash); + + // map and add to cache + + return bt_linklru(bt, hash, page_no); + } + + return bt->err = BTERR_hash, (BtPage)NULL; +} + +// map a btree page onto current page + +BTERR bt_mappage (BtDb *bt, BtPage *page, uid page_no) +{ +off64_t off = page_no << bt->page_bits; +#ifndef unix +int amt[1]; +#endif + + if( bt->mapped_io ) { + bt->err = 0; + *page = bt_hashpage(bt, page_no); + return bt->err; + } +#ifdef unix + if ( pread(bt->idx, *page, bt->page_size, off) < bt->page_size ) + return bt->err = BTERR_map; +#else + SetFilePointer (bt->idx, (long)off, (long*)(&off)+1, FILE_BEGIN); + + if( !ReadFile(bt->idx, *page, bt->page_size, amt, NULL) ) + return bt->err = BTERR_map; + + if( *amt < bt->page_size ) + return bt->err = BTERR_map; +#endif + return 0; +} + +// deallocate a deleted page +// place on free chain out of allocator page + +BTERR bt_freepage(BtDb *bt, uid page_no) +{ + // obtain delete lock on deleted node + + if( bt_lockpage(bt, page_no, BtLockDelete) ) + return bt->err; + + // obtain write lock on deleted node + + if( bt_lockpage(bt, page_no, BtLockWrite) ) + return bt->err; + + if( bt_mappage (bt, &bt->temp, page_no) ) + return bt->err; + + // lock allocation page + + if ( bt_lockpage(bt, ALLOC_page, BtLockWrite) ) + return bt->err; + + if( bt_mappage (bt, &bt->alloc, ALLOC_page) ) + return bt->err; + + // store chain in second right + bt_putid(bt->temp->right, bt_getid(bt->alloc[1].right)); + bt_putid(bt->alloc[1].right, page_no); + + if( bt_update(bt, bt->alloc, ALLOC_page) ) + return bt->err; + if( bt_update(bt, bt->temp, page_no) ) + return bt->err; + + // unlock page zero + + if( bt_unlockpage(bt, ALLOC_page, BtLockWrite) ) + return bt->err; + + // remove write lock on deleted node + + if( bt_unlockpage(bt, page_no, BtLockWrite) ) + return bt->err; + + // remove delete lock on deleted node + + if( bt_unlockpage(bt, page_no, BtLockDelete) ) + return bt->err; + + return 0; +} + +// allocate a new page and write page into it + +uid bt_newpage(BtDb *bt, BtPage page) +{ +uid new_page; +char *pmap; +int reuse; + + // lock page zero + + if ( bt_lockpage(bt, ALLOC_page, BtLockWrite) ) + return 0; + + if( bt_mappage (bt, &bt->alloc, ALLOC_page) ) + return 0; + + // use empty chain first + // else allocate empty page + + if( new_page = bt_getid(bt->alloc[1].right) ) { + if( bt_mappage (bt, &bt->temp, new_page) ) + return 0; // don't unlock on error + bt_putid(bt->alloc[1].right, bt_getid(bt->temp->right)); + reuse = 1; + } else { + new_page = bt_getid(bt->alloc->right); + bt_putid(bt->alloc->right, new_page+1); + reuse = 0; + } + + if( bt_update(bt, bt->alloc, ALLOC_page) ) + return 0; // don't unlock on error + + if( !bt->mapped_io ) { + if( bt_update(bt, page, new_page) ) + return 0; //don't unlock on error + + // unlock page zero + + if ( bt_unlockpage(bt, ALLOC_page, BtLockWrite) ) + return 0; + + return new_page; + } + +#ifdef unix + if ( pwrite(bt->idx, page, bt->page_size, new_page << bt->page_bits) < bt->page_size ) + return bt->err = BTERR_wrt, 0; + + // if writing first page of hash block, zero last page in the block + + if ( !reuse && bt->hashmask > 0 && (new_page & bt->hashmask) == 0 ) + { + // use temp buffer to write zeros + memset(bt->zero, 0, bt->page_size); + if ( pwrite(bt->idx,bt->zero, bt->page_size, (new_page | bt->hashmask) << bt->page_bits) < bt->page_size ) + return bt->err = BTERR_wrt, 0; + } +#else + // bring new page into page-cache and copy page. + // this will extend the file into the new pages. + + if( !(pmap = (char*)bt_hashpage(bt, new_page & ~bt->hashmask)) ) + return 0; + + memcpy(pmap+((new_page & bt->hashmask) << bt->page_bits), page, bt->page_size); +#endif + + // unlock page zero + + if ( bt_unlockpage(bt, ALLOC_page, BtLockWrite) ) + return 0; + + return new_page; +} + +// find slot in page for given key at a given level + +int bt_findslot (BtDb *bt, unsigned char *key, uint len) +{ +uint diff, higher = bt->page->cnt, low = 1, slot; +uint good = 0; + + // if page is being deleted, send to right + + if( !bt->page->cnt ) + return 0; + + // if page is an empty fence holder + + if( !bt->page->act ) + return bt->page->cnt; + + // make stopper key an infinite fence value + + if( bt_getid (bt->page->right) ) + higher++; + else + good++; + + // low is the next candidate, higher is already + // tested as .ge. the given key, loop ends when they meet + + while( diff = higher - low ) { + slot = low + ( diff >> 1 ); + if( keycmp (keyptr(bt->page, slot), key, len) < 0 ) + low = slot + 1; + else + higher = slot, good++; + } + + // return zero if key is on right link page + + return good ? higher : 0; +} + +// find and load page at given level for given key +// leave page rd or wr locked as requested + +int bt_loadpage (BtDb *bt, unsigned char *key, uint len, uint lvl, uint lock) +{ +uid page_no = ROOT_page, prevpage = 0; +uint drill = 0xff, slot; +uint mode, prevmode; + + // start at root of btree and drill down + + bt->posted = 1; + + do { + // determine lock mode of drill level + mode = (lock == BtLockWrite) && (drill == lvl) ? BtLockWrite : BtLockRead; + + bt->page_no = page_no; + + // obtain access lock using lock chaining + + if( page_no > ROOT_page ) + if( bt_lockpage(bt, bt->page_no, BtLockAccess) ) + return 0; + + if( prevpage ) + if( bt_unlockpage(bt, prevpage, prevmode) ) + return 0; + + // obtain read lock using lock chaining + + if( bt_lockpage(bt, bt->page_no, mode) ) + return 0; + + if( page_no > ROOT_page ) + if( bt_unlockpage(bt, bt->page_no, BtLockAccess) ) + return 0; + + // map/obtain page contents + + if( bt_mappage (bt, &bt->page, page_no) ) + return 0; + + // re-read and re-lock root after determining actual level of root + + if( bt->page->lvl != drill) { + if ( bt->page_no != ROOT_page ) + return bt->err = BTERR_struct, 0; + + drill = bt->page->lvl; + + if( lock == BtLockWrite && drill == lvl ) + if( bt_unlockpage(bt, page_no, mode) ) + return 0; + else + continue; + } + + // find key on page at this level + // and descend to requested level + + if( slot = bt_findslot (bt, key, len) ) { + if( drill == lvl ) + return slot; + + while( slotptr(bt->page, slot)->dead ) + if( slot++ < bt->page->cnt ) + continue; + else + return bt->err = BTERR_struct, 0; + + page_no = bt_getid(slotptr(bt->page, slot)->id); + bt->fence = slot == bt->page->cnt; + bt->posted = 1; + drill--; + } + + // or slide right into next page + // (slide left from deleted page) + + else { + page_no = bt_getid(bt->page->right); + bt->posted = 0; + } + + // continue down / right using overlapping locks + // to protect pages being killed or split. + + prevpage = bt->page_no; + prevmode = mode; + } while( page_no ); + + // return error on end of right chain + + bt->err = BTERR_struct; + return 0; // return error +} + +// find and delete key on page by marking delete flag bit +// when page becomes empty, delete it + +BTERR bt_deletekey (BtDb *bt, unsigned char *key, uint len, uint lvl) +{ +unsigned char lowerkey[256], higherkey[256]; +uint slot, tod, dirty = 0; +uid page_no, right; +BtKey ptr; + + if( slot = bt_loadpage (bt, key, len, lvl, BtLockWrite) ) + ptr = keyptr(bt->page, slot); + else + return bt->err; + + // if key is found delete it, otherwise ignore request + + if( !keycmp (ptr, key, len) ) + if( slotptr(bt->page, slot)->dead == 0 ) { + dirty = slotptr(bt->page,slot)->dead = 1; + if( slot < bt->page->cnt ) + bt->page->dirty = 1; + bt->page->act--; + } + + // return if page is not empty, or + // if non-leaf level or fence key + + right = bt_getid(bt->page->right); + page_no = bt->page_no; + + if( lvl || bt->page->act || bt->fence ) + if ( dirty && bt_update(bt, bt->page, page_no) ) + return bt->err; + else + return bt_unlockpage(bt, page_no, BtLockWrite); + + // obtain Parent lock over write lock + + if( bt_lockpage(bt, page_no, BtLockParent) ) + return bt->err; + + // cache copy of fence key + // in order to find parent + + ptr = keyptr(bt->page, bt->page->cnt); + memcpy(lowerkey, ptr, ptr->len + 1); + + // lock and map right page + + if ( bt_lockpage(bt, right, BtLockWrite) ) + return bt->err; + + if( bt_mappage (bt, &bt->temp, right) ) + return bt->err; + + // pull contents of next page into current empty page + + memcpy (bt->page, bt->temp, bt->page_size); + + // cache copy of key to update + + ptr = keyptr(bt->temp, bt->temp->cnt); + memcpy(higherkey, ptr, ptr->len + 1); + + // Mark right page as deleted and point it to left page + // until we can post updates at higher level. + + bt_putid(bt->temp->right, page_no); + bt->temp->cnt = 0; + + if( bt_update(bt, bt->page, page_no) ) + return bt->err; + + if( bt_update(bt, bt->temp, right) ) + return bt->err; + + if( bt_unlockpage(bt, right, BtLockWrite) ) + return bt->err; + + if( bt_unlockpage(bt, page_no, BtLockWrite) ) + return bt->err; + + // delete old lower key to consolidated node + + if( bt_deletekey (bt, lowerkey + 1, *lowerkey, lvl + 1) ) + return bt->err; + + // redirect higher key directly to consolidated node + + tod = (uint)time(NULL); + + if( bt_insertkey (bt, higherkey+1, *higherkey, lvl + 1, page_no, tod) ) + return bt->err; + + // obtain write lock and + // add right block to free chain + + if( bt_freepage (bt, right) ) + return bt->err; + + // remove ParentModify lock + + if( bt_unlockpage(bt, page_no, BtLockParent) ) + return bt->err; + + return 0; +} + +// find key in leaf level and return row-id + +uid bt_findkey (BtDb *bt, unsigned char *key, uint len) +{ +uint slot; +BtKey ptr; +uid id; + + if( slot = bt_loadpage (bt, key, len, 0, BtLockRead) ) + ptr = keyptr(bt->page, slot); + else + return 0; + + // if key exists, return row-id + // otherwise return 0 + + if( ptr->len == len && !memcmp (ptr->key, key, len) ) + id = bt_getid(slotptr(bt->page,slot)->id); + else + id = 0; + + if ( bt_unlockpage(bt, bt->page_no, BtLockRead) ) + return 0; + + return id; +} + +// check page for space available, +// clean if necessary and return +// 0 - page needs splitting +// >0 - go ahead with new slot + +uint bt_cleanpage(BtDb *bt, uint amt, uint slot) +{ +uint nxt = bt->page_size; +BtPage page = bt->page; +uint cnt = 0, idx = 0; +uint max = page->cnt; +uint newslot = slot; +BtKey key; +int ret; + + if( page->min >= (max+1) * sizeof(BtSlot) + sizeof(*page) + amt + 1 ) + return slot; + + // skip cleanup if nothing to reclaim + + if( !page->dirty ) + return 0; + + memcpy (bt->frame, page, bt->page_size); + + // skip page info and set rest of page to zero + + memset (page+1, 0, bt->page_size - sizeof(*page)); + page->act = 0; + + while( cnt++ < max ) { + if( cnt == slot ) + newslot = idx + 1; + // always leave fence key in list + if( cnt < max && slotptr(bt->frame,cnt)->dead ) + continue; + + // copy key + key = keyptr(bt->frame, cnt); + nxt -= key->len + 1; + memcpy ((unsigned char *)page + nxt, key, key->len + 1); + + // copy slot + memcpy(slotptr(page, ++idx)->id, slotptr(bt->frame, cnt)->id, BtId); + if( !(slotptr(page, idx)->dead = slotptr(bt->frame, cnt)->dead) ) + page->act++; + slotptr(page, idx)->tod = slotptr(bt->frame, cnt)->tod; + slotptr(page, idx)->off = nxt; + } + + page->min = nxt; + page->cnt = idx; + + if( page->min >= (max+1) * sizeof(BtSlot) + sizeof(*page) + amt + 1 ) + return newslot; + + return 0; +} + +// split the root and raise the height of the btree + +BTERR bt_splitroot(BtDb *bt, unsigned char *newkey, unsigned char *oldkey, uid page_no2) +{ +uint nxt = bt->page_size; +BtPage root = bt->page; +uid new_page; + + // Obtain an empty page to use, and copy the current + // root contents into it + + if( !(new_page = bt_newpage(bt, root)) ) + return bt->err; + + // preserve the page info at the bottom + // and set rest to zero + + memset(root+1, 0, bt->page_size - sizeof(*root)); + + // insert first key on newroot page + + nxt -= *newkey + 1; + memcpy ((unsigned char *)root + nxt, newkey, *newkey + 1); + bt_putid(slotptr(root, 1)->id, new_page); + slotptr(root, 1)->off = nxt; + + // insert second key on newroot page + // and increase the root height + + nxt -= *oldkey + 1; + memcpy ((unsigned char *)root + nxt, oldkey, *oldkey + 1); + bt_putid(slotptr(root, 2)->id, page_no2); + slotptr(root, 2)->off = nxt; + + bt_putid(root->right, 0); + root->min = nxt; // reset lowest used offset and key count + root->cnt = 2; + root->act = 2; + root->lvl++; + + // update and release root (bt->page) + + if( bt_update(bt, root, bt->page_no) ) + return bt->err; + + return bt_unlockpage(bt, bt->page_no, BtLockWrite); +} + +// split already locked full node +// return unlocked. + +BTERR bt_splitpage (BtDb *bt) +{ +uint cnt = 0, idx = 0, max, nxt = bt->page_size; +unsigned char oldkey[256], lowerkey[256]; +uid page_no = bt->page_no, right; +BtPage page = bt->page; +uint lvl = page->lvl; +uid new_page; +BtKey key; +uint tod; + + // split higher half of keys to bt->frame + // the last key (fence key) might be dead + + tod = (uint)time(NULL); + + memset (bt->frame, 0, bt->page_size); + max = (int)page->cnt; + cnt = max / 2; + idx = 0; + + while( cnt++ < max ) { + key = keyptr(page, cnt); + nxt -= key->len + 1; + memcpy ((unsigned char *)bt->frame + nxt, key, key->len + 1); + memcpy(slotptr(bt->frame,++idx)->id, slotptr(page,cnt)->id, BtId); + if( !(slotptr(bt->frame, idx)->dead = slotptr(page, cnt)->dead) ) + bt->frame->act++; + slotptr(bt->frame, idx)->tod = slotptr(page, cnt)->tod; + slotptr(bt->frame, idx)->off = nxt; + } + + // remember existing fence key for new page to the right + + memcpy (oldkey, key, key->len + 1); + + bt->frame->bits = bt->page_bits; + bt->frame->min = nxt; + bt->frame->cnt = idx; + bt->frame->lvl = lvl; + + // link right node + + if( page_no > ROOT_page ) { + right = bt_getid (page->right); + bt_putid(bt->frame->right, right); + } + + // get new free page and write frame to it. + + if( !(new_page = bt_newpage(bt, bt->frame)) ) + return bt->err; + + // update lower keys to continue in old page + + memcpy (bt->frame, page, bt->page_size); + memset (page+1, 0, bt->page_size - sizeof(*page)); + nxt = bt->page_size; + page->act = 0; + cnt = 0; + idx = 0; + + // assemble page of smaller keys + // (they're all active keys) + + while( cnt++ < max / 2 ) { + key = keyptr(bt->frame, cnt); + nxt -= key->len + 1; + memcpy ((unsigned char *)page + nxt, key, key->len + 1); + memcpy(slotptr(page,++idx)->id, slotptr(bt->frame,cnt)->id, BtId); + slotptr(page, idx)->tod = slotptr(bt->frame, cnt)->tod; + slotptr(page, idx)->off = nxt; + page->act++; + } + + // remember fence key for old page + + memcpy(lowerkey, key, key->len + 1); + bt_putid(page->right, new_page); + page->min = nxt; + page->cnt = idx; + + // if current page is the root page, split it + + if( page_no == ROOT_page ) + return bt_splitroot (bt, lowerkey, oldkey, new_page); + + // update left (containing) node + + if( bt_update(bt, page, page_no) ) + return bt->err; + + // obtain Parent/Write locks + // for left and right node pages + + if( bt_lockpage (bt, new_page, BtLockParent) ) + return bt->err; + + if( bt_lockpage (bt, page_no, BtLockParent) ) + return bt->err; + + // release wr lock on left page + + if( bt_unlockpage (bt, page_no, BtLockWrite) ) + return bt->err; + + // insert new fence for reformulated left block + + if( bt_insertkey (bt, lowerkey+1, *lowerkey, lvl + 1, page_no, tod) ) + return bt->err; + + // fix old fence for newly allocated right block page + + if( bt_insertkey (bt, oldkey+1, *oldkey, lvl + 1, new_page, tod) ) + return bt->err; + + // release Parent & Write locks + + if( bt_unlockpage (bt, new_page, BtLockParent) ) + return bt->err; + + if( bt_unlockpage (bt, page_no, BtLockParent) ) + return bt->err; + + return 0; +} + +// Insert new key into the btree at requested level. +// Level zero pages are leaf pages and are unlocked at exit. +// Interior nodes remain locked. + +BTERR bt_insertkey (BtDb *bt, unsigned char *key, uint len, uint lvl, uid id, uint tod) +{ +uint slot, idx; +BtPage page; +BtKey ptr; + + while( 1 ) { + if( slot = bt_loadpage (bt, key, len, lvl, BtLockWrite) ) + ptr = keyptr(bt->page, slot); + else + { + if ( !bt->err ) + bt->err = BTERR_ovflw; + return bt->err; + } + + // if key already exists, update id and return + + page = bt->page; + + if( !keycmp (ptr, key, len) ) { + slotptr(page, slot)->dead = 0; + slotptr(page, slot)->tod = tod; + bt_putid(slotptr(page,slot)->id, id); + if ( bt_update(bt, bt->page, bt->page_no) ) + return bt->err; + return bt_unlockpage(bt, bt->page_no, BtLockWrite); + } + + // check if page has enough space + + if( slot = bt_cleanpage (bt, len, slot) ) + break; + + if( bt_splitpage (bt) ) + return bt->err; + } + + // calculate next available slot and copy key into page + + page->min -= len + 1; // reset lowest used offset + ((unsigned char *)page)[page->min] = len; + memcpy ((unsigned char *)page + page->min +1, key, len ); + + for( idx = slot; idx < page->cnt; idx++ ) + if( slotptr(page, idx)->dead ) + break; + + // now insert key into array before slot + // preserving the fence slot + + if( idx == page->cnt ) + idx++, page->cnt++; + + page->act++; + + while( idx > slot ) + *slotptr(page, idx) = *slotptr(page, idx -1), idx--; + + bt_putid(slotptr(page,slot)->id, id); + slotptr(page, slot)->off = page->min; + slotptr(page, slot)->tod = tod; + slotptr(page, slot)->dead = 0; + + if ( bt_update(bt, bt->page, bt->page_no) ) + return bt->err; + + return bt_unlockpage(bt, bt->page_no, BtLockWrite); +} + +// cache page of keys into cursor and return starting slot for given key + +uint bt_startkey (BtDb *bt, unsigned char *key, uint len) +{ +uint slot; + + // cache page for retrieval + if( slot = bt_loadpage (bt, key, len, 0, BtLockRead) ) + memcpy (bt->cursor, bt->page, bt->page_size); + bt->cursor_page = bt->page_no; + if ( bt_unlockpage(bt, bt->page_no, BtLockRead) ) + return 0; + + return slot; +} + +// return next slot for cursor page +// or slide cursor right into next page + +uint bt_nextkey (BtDb *bt, uint slot) +{ +off64_t 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)) + return slot; + else + break; + + if( !right ) + break; + + bt->cursor_page = right; + + if( bt_lockpage(bt, right,BtLockRead) ) + return 0; + + if( bt_mappage (bt, &bt->page, right) ) + break; + + memcpy (bt->cursor, bt->page, bt->page_size); + if ( bt_unlockpage(bt, right, BtLockRead) ) + return 0; + + slot = 0; + } while( 1 ); + + return bt->err = 0; +} + +BtKey bt_key(BtDb *bt, uint slot) +{ + return keyptr(bt->cursor, slot); +} + +uid bt_uid(BtDb *bt, uint slot) +{ + return bt_getid(slotptr(bt->cursor,slot)->id); +} + +uint bt_tod(BtDb *bt, uint slot) +{ + return slotptr(bt->cursor,slot)->tod; +} + + +#ifdef STANDALONE +// standalone program to index file of keys +// then list them onto std-out + +int main (int argc, char **argv) +{ +uint slot, line = 0, off = 0, found = 0; +int dead, ch, cnt = 0, bits = 12; +unsigned char key[256]; +clock_t done, start; +uint pgblk = 0; +time_t tod[1]; +uint scan = 0; +uint len = 0; +uint map = 0; +BtKey ptr; +BtDb *bt; +FILE *in; + + if( argc < 4 ) { + fprintf (stderr, "Usage: %s idx_file src_file Read/Write/Scan/Delete/Find [page_bits mapped_pool_segments pages_per_segment start_line_number]\n", argv[0]); + fprintf (stderr, " page_bits: size of btree page in bits\n"); + fprintf (stderr, " mapped_pool_segments: size of buffer pool in segments\n"); + fprintf (stderr, " pages_per_segment: size of buffer pool segment in pages in bits\n"); + exit(0); + } + + start = clock(); + time(tod); + + if( argc > 4 ) + bits = atoi(argv[4]); + + if( argc > 5 ) + map = atoi(argv[5]); + + if( map > 65536 ) + fprintf (stderr, "Warning: buffer_pool > 65536 segments\n"); + + if( map && map < 8 ) + fprintf (stderr, "Buffer_pool too small\n"); + + if( argc > 6 ) + pgblk = atoi(argv[6]); + + if( bits + pgblk > 30 ) + fprintf (stderr, "Warning: very large buffer pool segment size\n"); + + if( argc > 7 ) + off = atoi(argv[7]); + + bt = bt_open ((argv[1]), BT_rw, bits, map, pgblk); + + if( !bt ) { + fprintf(stderr, "Index Open Error %s\n", argv[1]); + exit (1); + } + + switch(argv[3][0]| 0x20) + { + case 'w': + fprintf(stderr, "started indexing for %s\n", argv[2]); + if( argc > 2 && (in = fopen (argv[2], "rb")) ) + while( ch = getc(in), ch != EOF ) + if( ch == '\n' ) + { + if( off ) + sprintf((char *)key+len, "%.9d", line + off), len += 9; + + if( bt_insertkey (bt, key, len, 0, ++line, *tod) ) + fprintf(stderr, "Error %d Line: %d\n", bt->err, line), exit(0); + len = 0; + } + else if( len < 245 ) + key[len++] = ch; + fprintf(stderr, "finished adding keys, %d \n", line); + break; + + case 'd': + fprintf(stderr, "started deleting keys for %s\n", argv[2]); + if( argc > 2 && (in = fopen (argv[2], "rb")) ) + while( ch = getc(in), ch != EOF ) + if( ch == '\n' ) + { + if( off ) + sprintf((char *)key+len, "%.9d", line + off), len += 9; + line++; + if( bt_deletekey (bt, key, len, 0) ) + fprintf(stderr, "Error %d Line: %d\n", bt->err, line), exit(0); + len = 0; + } + else if( len < 245 ) + key[len++] = ch; + fprintf(stderr, "finished deleting keys, %d \n", line); + break; + + case 'f': + fprintf(stderr, "started finding keys for %s\n", argv[2]); + if( argc > 2 && (in = fopen (argv[2], "rb")) ) + while( ch = getc(in), ch != EOF ) + if( ch == '\n' ) + { + if( off ) + sprintf((char *)key+len, "%.9d", line + off), len += 9; + line++; + if( bt_findkey (bt, key, len) ) + found++; + else if( bt->err ) + fprintf(stderr, "Error %d Syserr %d Line: %d\n", bt->err, errno, line), exit(0); + len = 0; + } + else if( len < 245 ) + key[len++] = ch; + fprintf(stderr, "finished search of %d keys, found %d\n", line, found); + break; + + case 's': + scan++; + break; + + } + + done = clock(); + fprintf(stderr, " Time to complete: %.2f seconds\n", (float)(done - start) / CLOCKS_PER_SEC); + + dead = cnt = 0; + len = key[0] = 0; + + fprintf(stderr, "started reading\n"); + + if( slot = bt_startkey (bt, key, len) ) + slot--; + else + fprintf(stderr, "Error %d in StartKey. Syserror: %d\n", bt->err, errno), exit(0); + + while( slot = bt_nextkey (bt, slot) ) + if( cnt++, scan ) { + ptr = bt_key(bt, slot); + fwrite (ptr->key, ptr->len, 1, stdout); + fputc ('\n', stdout); + } + + fprintf(stderr, " Total keys read %d\n", cnt); + return 0; +} + +#endif //STANDALONE