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author | 2016-09-23 09:21:58 +0000 | |
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committer | 2016-09-23 09:21:58 +0000 | |
commit | 25e4f8ab5acd0ef40feec6767a572bebbbe294b3 (patch) | |
tree | 20197c0e46bb6d260f4a310b6d5dd73b8d826f01 /lib/libsqlite3/src/rowset.c | |
parent | remove usr.bin/sqlite3, it has moved back to ports (diff) | |
download | wireguard-openbsd-25e4f8ab5acd0ef40feec6767a572bebbbe294b3.tar.xz wireguard-openbsd-25e4f8ab5acd0ef40feec6767a572bebbbe294b3.zip |
remove lib/libsqlite3, it has moved back to ports
Diffstat (limited to 'lib/libsqlite3/src/rowset.c')
-rw-r--r-- | lib/libsqlite3/src/rowset.c | 508 |
1 files changed, 0 insertions, 508 deletions
diff --git a/lib/libsqlite3/src/rowset.c b/lib/libsqlite3/src/rowset.c deleted file mode 100644 index ff5593892ab..00000000000 --- a/lib/libsqlite3/src/rowset.c +++ /dev/null @@ -1,508 +0,0 @@ -/* -** 2008 December 3 -** -** The author disclaims copyright to this source code. In place of -** a legal notice, here is a blessing: -** -** May you do good and not evil. -** May you find forgiveness for yourself and forgive others. -** May you share freely, never taking more than you give. -** -************************************************************************* -** -** This module implements an object we call a "RowSet". -** -** The RowSet object is a collection of rowids. Rowids -** are inserted into the RowSet in an arbitrary order. Inserts -** can be intermixed with tests to see if a given rowid has been -** previously inserted into the RowSet. -** -** After all inserts are finished, it is possible to extract the -** elements of the RowSet in sorted order. Once this extraction -** process has started, no new elements may be inserted. -** -** Hence, the primitive operations for a RowSet are: -** -** CREATE -** INSERT -** TEST -** SMALLEST -** DESTROY -** -** The CREATE and DESTROY primitives are the constructor and destructor, -** obviously. The INSERT primitive adds a new element to the RowSet. -** TEST checks to see if an element is already in the RowSet. SMALLEST -** extracts the least value from the RowSet. -** -** The INSERT primitive might allocate additional memory. Memory is -** allocated in chunks so most INSERTs do no allocation. There is an -** upper bound on the size of allocated memory. No memory is freed -** until DESTROY. -** -** The TEST primitive includes a "batch" number. The TEST primitive -** will only see elements that were inserted before the last change -** in the batch number. In other words, if an INSERT occurs between -** two TESTs where the TESTs have the same batch nubmer, then the -** value added by the INSERT will not be visible to the second TEST. -** The initial batch number is zero, so if the very first TEST contains -** a non-zero batch number, it will see all prior INSERTs. -** -** No INSERTs may occurs after a SMALLEST. An assertion will fail if -** that is attempted. -** -** The cost of an INSERT is roughly constant. (Sometimes new memory -** has to be allocated on an INSERT.) The cost of a TEST with a new -** batch number is O(NlogN) where N is the number of elements in the RowSet. -** The cost of a TEST using the same batch number is O(logN). The cost -** of the first SMALLEST is O(NlogN). Second and subsequent SMALLEST -** primitives are constant time. The cost of DESTROY is O(N). -** -** There is an added cost of O(N) when switching between TEST and -** SMALLEST primitives. -*/ -#include "sqliteInt.h" - - -/* -** Target size for allocation chunks. -*/ -#define ROWSET_ALLOCATION_SIZE 1024 - -/* -** The number of rowset entries per allocation chunk. -*/ -#define ROWSET_ENTRY_PER_CHUNK \ - ((ROWSET_ALLOCATION_SIZE-8)/sizeof(struct RowSetEntry)) - -/* -** Each entry in a RowSet is an instance of the following object. -** -** This same object is reused to store a linked list of trees of RowSetEntry -** objects. In that alternative use, pRight points to the next entry -** in the list, pLeft points to the tree, and v is unused. The -** RowSet.pForest value points to the head of this forest list. -*/ -struct RowSetEntry { - i64 v; /* ROWID value for this entry */ - struct RowSetEntry *pRight; /* Right subtree (larger entries) or list */ - struct RowSetEntry *pLeft; /* Left subtree (smaller entries) */ -}; - -/* -** RowSetEntry objects are allocated in large chunks (instances of the -** following structure) to reduce memory allocation overhead. The -** chunks are kept on a linked list so that they can be deallocated -** when the RowSet is destroyed. -*/ -struct RowSetChunk { - struct RowSetChunk *pNextChunk; /* Next chunk on list of them all */ - struct RowSetEntry aEntry[ROWSET_ENTRY_PER_CHUNK]; /* Allocated entries */ -}; - -/* -** A RowSet in an instance of the following structure. -** -** A typedef of this structure if found in sqliteInt.h. -*/ -struct RowSet { - struct RowSetChunk *pChunk; /* List of all chunk allocations */ - sqlite3 *db; /* The database connection */ - struct RowSetEntry *pEntry; /* List of entries using pRight */ - struct RowSetEntry *pLast; /* Last entry on the pEntry list */ - struct RowSetEntry *pFresh; /* Source of new entry objects */ - struct RowSetEntry *pForest; /* List of binary trees of entries */ - u16 nFresh; /* Number of objects on pFresh */ - u16 rsFlags; /* Various flags */ - int iBatch; /* Current insert batch */ -}; - -/* -** Allowed values for RowSet.rsFlags -*/ -#define ROWSET_SORTED 0x01 /* True if RowSet.pEntry is sorted */ -#define ROWSET_NEXT 0x02 /* True if sqlite3RowSetNext() has been called */ - -/* -** Turn bulk memory into a RowSet object. N bytes of memory -** are available at pSpace. The db pointer is used as a memory context -** for any subsequent allocations that need to occur. -** Return a pointer to the new RowSet object. -** -** It must be the case that N is sufficient to make a Rowset. If not -** an assertion fault occurs. -** -** If N is larger than the minimum, use the surplus as an initial -** allocation of entries available to be filled. -*/ -RowSet *sqlite3RowSetInit(sqlite3 *db, void *pSpace, unsigned int N){ - RowSet *p; - assert( N >= ROUND8(sizeof(*p)) ); - p = pSpace; - p->pChunk = 0; - p->db = db; - p->pEntry = 0; - p->pLast = 0; - p->pForest = 0; - p->pFresh = (struct RowSetEntry*)(ROUND8(sizeof(*p)) + (char*)p); - p->nFresh = (u16)((N - ROUND8(sizeof(*p)))/sizeof(struct RowSetEntry)); - p->rsFlags = ROWSET_SORTED; - p->iBatch = 0; - return p; -} - -/* -** Deallocate all chunks from a RowSet. This frees all memory that -** the RowSet has allocated over its lifetime. This routine is -** the destructor for the RowSet. -*/ -void sqlite3RowSetClear(RowSet *p){ - struct RowSetChunk *pChunk, *pNextChunk; - for(pChunk=p->pChunk; pChunk; pChunk = pNextChunk){ - pNextChunk = pChunk->pNextChunk; - sqlite3DbFree(p->db, pChunk); - } - p->pChunk = 0; - p->nFresh = 0; - p->pEntry = 0; - p->pLast = 0; - p->pForest = 0; - p->rsFlags = ROWSET_SORTED; -} - -/* -** Allocate a new RowSetEntry object that is associated with the -** given RowSet. Return a pointer to the new and completely uninitialized -** objected. -** -** In an OOM situation, the RowSet.db->mallocFailed flag is set and this -** routine returns NULL. -*/ -static struct RowSetEntry *rowSetEntryAlloc(RowSet *p){ - assert( p!=0 ); - if( p->nFresh==0 ){ - struct RowSetChunk *pNew; - pNew = sqlite3DbMallocRaw(p->db, sizeof(*pNew)); - if( pNew==0 ){ - return 0; - } - pNew->pNextChunk = p->pChunk; - p->pChunk = pNew; - p->pFresh = pNew->aEntry; - p->nFresh = ROWSET_ENTRY_PER_CHUNK; - } - p->nFresh--; - return p->pFresh++; -} - -/* -** Insert a new value into a RowSet. -** -** The mallocFailed flag of the database connection is set if a -** memory allocation fails. -*/ -void sqlite3RowSetInsert(RowSet *p, i64 rowid){ - struct RowSetEntry *pEntry; /* The new entry */ - struct RowSetEntry *pLast; /* The last prior entry */ - - /* This routine is never called after sqlite3RowSetNext() */ - assert( p!=0 && (p->rsFlags & ROWSET_NEXT)==0 ); - - pEntry = rowSetEntryAlloc(p); - if( pEntry==0 ) return; - pEntry->v = rowid; - pEntry->pRight = 0; - pLast = p->pLast; - if( pLast ){ - if( (p->rsFlags & ROWSET_SORTED)!=0 && rowid<=pLast->v ){ - p->rsFlags &= ~ROWSET_SORTED; - } - pLast->pRight = pEntry; - }else{ - p->pEntry = pEntry; - } - p->pLast = pEntry; -} - -/* -** Merge two lists of RowSetEntry objects. Remove duplicates. -** -** The input lists are connected via pRight pointers and are -** assumed to each already be in sorted order. -*/ -static struct RowSetEntry *rowSetEntryMerge( - struct RowSetEntry *pA, /* First sorted list to be merged */ - struct RowSetEntry *pB /* Second sorted list to be merged */ -){ - struct RowSetEntry head; - struct RowSetEntry *pTail; - - pTail = &head; - while( pA && pB ){ - assert( pA->pRight==0 || pA->v<=pA->pRight->v ); - assert( pB->pRight==0 || pB->v<=pB->pRight->v ); - if( pA->v<pB->v ){ - pTail->pRight = pA; - pA = pA->pRight; - pTail = pTail->pRight; - }else if( pB->v<pA->v ){ - pTail->pRight = pB; - pB = pB->pRight; - pTail = pTail->pRight; - }else{ - pA = pA->pRight; - } - } - if( pA ){ - assert( pA->pRight==0 || pA->v<=pA->pRight->v ); - pTail->pRight = pA; - }else{ - assert( pB==0 || pB->pRight==0 || pB->v<=pB->pRight->v ); - pTail->pRight = pB; - } - return head.pRight; -} - -/* -** Sort all elements on the list of RowSetEntry objects into order of -** increasing v. -*/ -static struct RowSetEntry *rowSetEntrySort(struct RowSetEntry *pIn){ - unsigned int i; - struct RowSetEntry *pNext, *aBucket[40]; - - memset(aBucket, 0, sizeof(aBucket)); - while( pIn ){ - pNext = pIn->pRight; - pIn->pRight = 0; - for(i=0; aBucket[i]; i++){ - pIn = rowSetEntryMerge(aBucket[i], pIn); - aBucket[i] = 0; - } - aBucket[i] = pIn; - pIn = pNext; - } - pIn = 0; - for(i=0; i<sizeof(aBucket)/sizeof(aBucket[0]); i++){ - pIn = rowSetEntryMerge(pIn, aBucket[i]); - } - return pIn; -} - - -/* -** The input, pIn, is a binary tree (or subtree) of RowSetEntry objects. -** Convert this tree into a linked list connected by the pRight pointers -** and return pointers to the first and last elements of the new list. -*/ -static void rowSetTreeToList( - struct RowSetEntry *pIn, /* Root of the input tree */ - struct RowSetEntry **ppFirst, /* Write head of the output list here */ - struct RowSetEntry **ppLast /* Write tail of the output list here */ -){ - assert( pIn!=0 ); - if( pIn->pLeft ){ - struct RowSetEntry *p; - rowSetTreeToList(pIn->pLeft, ppFirst, &p); - p->pRight = pIn; - }else{ - *ppFirst = pIn; - } - if( pIn->pRight ){ - rowSetTreeToList(pIn->pRight, &pIn->pRight, ppLast); - }else{ - *ppLast = pIn; - } - assert( (*ppLast)->pRight==0 ); -} - - -/* -** Convert a sorted list of elements (connected by pRight) into a binary -** tree with depth of iDepth. A depth of 1 means the tree contains a single -** node taken from the head of *ppList. A depth of 2 means a tree with -** three nodes. And so forth. -** -** Use as many entries from the input list as required and update the -** *ppList to point to the unused elements of the list. If the input -** list contains too few elements, then construct an incomplete tree -** and leave *ppList set to NULL. -** -** Return a pointer to the root of the constructed binary tree. -*/ -static struct RowSetEntry *rowSetNDeepTree( - struct RowSetEntry **ppList, - int iDepth -){ - struct RowSetEntry *p; /* Root of the new tree */ - struct RowSetEntry *pLeft; /* Left subtree */ - if( *ppList==0 ){ - return 0; - } - if( iDepth==1 ){ - p = *ppList; - *ppList = p->pRight; - p->pLeft = p->pRight = 0; - return p; - } - pLeft = rowSetNDeepTree(ppList, iDepth-1); - p = *ppList; - if( p==0 ){ - return pLeft; - } - p->pLeft = pLeft; - *ppList = p->pRight; - p->pRight = rowSetNDeepTree(ppList, iDepth-1); - return p; -} - -/* -** Convert a sorted list of elements into a binary tree. Make the tree -** as deep as it needs to be in order to contain the entire list. -*/ -static struct RowSetEntry *rowSetListToTree(struct RowSetEntry *pList){ - int iDepth; /* Depth of the tree so far */ - struct RowSetEntry *p; /* Current tree root */ - struct RowSetEntry *pLeft; /* Left subtree */ - - assert( pList!=0 ); - p = pList; - pList = p->pRight; - p->pLeft = p->pRight = 0; - for(iDepth=1; pList; iDepth++){ - pLeft = p; - p = pList; - pList = p->pRight; - p->pLeft = pLeft; - p->pRight = rowSetNDeepTree(&pList, iDepth); - } - return p; -} - -/* -** Take all the entries on p->pEntry and on the trees in p->pForest and -** sort them all together into one big ordered list on p->pEntry. -** -** This routine should only be called once in the life of a RowSet. -*/ -static void rowSetToList(RowSet *p){ - - /* This routine is called only once */ - assert( p!=0 && (p->rsFlags & ROWSET_NEXT)==0 ); - - if( (p->rsFlags & ROWSET_SORTED)==0 ){ - p->pEntry = rowSetEntrySort(p->pEntry); - } - - /* While this module could theoretically support it, sqlite3RowSetNext() - ** is never called after sqlite3RowSetText() for the same RowSet. So - ** there is never a forest to deal with. Should this change, simply - ** remove the assert() and the #if 0. */ - assert( p->pForest==0 ); -#if 0 - while( p->pForest ){ - struct RowSetEntry *pTree = p->pForest->pLeft; - if( pTree ){ - struct RowSetEntry *pHead, *pTail; - rowSetTreeToList(pTree, &pHead, &pTail); - p->pEntry = rowSetEntryMerge(p->pEntry, pHead); - } - p->pForest = p->pForest->pRight; - } -#endif - p->rsFlags |= ROWSET_NEXT; /* Verify this routine is never called again */ -} - -/* -** Extract the smallest element from the RowSet. -** Write the element into *pRowid. Return 1 on success. Return -** 0 if the RowSet is already empty. -** -** After this routine has been called, the sqlite3RowSetInsert() -** routine may not be called again. -*/ -int sqlite3RowSetNext(RowSet *p, i64 *pRowid){ - assert( p!=0 ); - - /* Merge the forest into a single sorted list on first call */ - if( (p->rsFlags & ROWSET_NEXT)==0 ) rowSetToList(p); - - /* Return the next entry on the list */ - if( p->pEntry ){ - *pRowid = p->pEntry->v; - p->pEntry = p->pEntry->pRight; - if( p->pEntry==0 ){ - sqlite3RowSetClear(p); - } - return 1; - }else{ - return 0; - } -} - -/* -** Check to see if element iRowid was inserted into the rowset as -** part of any insert batch prior to iBatch. Return 1 or 0. -** -** If this is the first test of a new batch and if there exist entries -** on pRowSet->pEntry, then sort those entries into the forest at -** pRowSet->pForest so that they can be tested. -*/ -int sqlite3RowSetTest(RowSet *pRowSet, int iBatch, sqlite3_int64 iRowid){ - struct RowSetEntry *p, *pTree; - - /* This routine is never called after sqlite3RowSetNext() */ - assert( pRowSet!=0 && (pRowSet->rsFlags & ROWSET_NEXT)==0 ); - - /* Sort entries into the forest on the first test of a new batch - */ - if( iBatch!=pRowSet->iBatch ){ - p = pRowSet->pEntry; - if( p ){ - struct RowSetEntry **ppPrevTree = &pRowSet->pForest; - if( (pRowSet->rsFlags & ROWSET_SORTED)==0 ){ - p = rowSetEntrySort(p); - } - for(pTree = pRowSet->pForest; pTree; pTree=pTree->pRight){ - ppPrevTree = &pTree->pRight; - if( pTree->pLeft==0 ){ - pTree->pLeft = rowSetListToTree(p); - break; - }else{ - struct RowSetEntry *pAux, *pTail; - rowSetTreeToList(pTree->pLeft, &pAux, &pTail); - pTree->pLeft = 0; - p = rowSetEntryMerge(pAux, p); - } - } - if( pTree==0 ){ - *ppPrevTree = pTree = rowSetEntryAlloc(pRowSet); - if( pTree ){ - pTree->v = 0; - pTree->pRight = 0; - pTree->pLeft = rowSetListToTree(p); - } - } - pRowSet->pEntry = 0; - pRowSet->pLast = 0; - pRowSet->rsFlags |= ROWSET_SORTED; - } - pRowSet->iBatch = iBatch; - } - - /* Test to see if the iRowid value appears anywhere in the forest. - ** Return 1 if it does and 0 if not. - */ - for(pTree = pRowSet->pForest; pTree; pTree=pTree->pRight){ - p = pTree->pLeft; - while( p ){ - if( p->v<iRowid ){ - p = p->pRight; - }else if( p->v>iRowid ){ - p = p->pLeft; - }else{ - return 1; - } - } - } - return 0; -} |