Index: third_party/sqlite/sqlite-src-3070603/ext/rtree/rtree.c |
diff --git a/third_party/sqlite/sqlite-src-3070603/ext/rtree/rtree.c b/third_party/sqlite/sqlite-src-3070603/ext/rtree/rtree.c |
new file mode 100644 |
index 0000000000000000000000000000000000000000..ebf430a98c6218d3970fa3dafd977c20c8aee46b |
--- /dev/null |
+++ b/third_party/sqlite/sqlite-src-3070603/ext/rtree/rtree.c |
@@ -0,0 +1,3238 @@ |
+/* |
+** 2001 September 15 |
+** |
+** 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 file contains code for implementations of the r-tree and r*-tree |
+** algorithms packaged as an SQLite virtual table module. |
+*/ |
+ |
+/* |
+** Database Format of R-Tree Tables |
+** -------------------------------- |
+** |
+** The data structure for a single virtual r-tree table is stored in three |
+** native SQLite tables declared as follows. In each case, the '%' character |
+** in the table name is replaced with the user-supplied name of the r-tree |
+** table. |
+** |
+** CREATE TABLE %_node(nodeno INTEGER PRIMARY KEY, data BLOB) |
+** CREATE TABLE %_parent(nodeno INTEGER PRIMARY KEY, parentnode INTEGER) |
+** CREATE TABLE %_rowid(rowid INTEGER PRIMARY KEY, nodeno INTEGER) |
+** |
+** The data for each node of the r-tree structure is stored in the %_node |
+** table. For each node that is not the root node of the r-tree, there is |
+** an entry in the %_parent table associating the node with its parent. |
+** And for each row of data in the table, there is an entry in the %_rowid |
+** table that maps from the entries rowid to the id of the node that it |
+** is stored on. |
+** |
+** The root node of an r-tree always exists, even if the r-tree table is |
+** empty. The nodeno of the root node is always 1. All other nodes in the |
+** table must be the same size as the root node. The content of each node |
+** is formatted as follows: |
+** |
+** 1. If the node is the root node (node 1), then the first 2 bytes |
+** of the node contain the tree depth as a big-endian integer. |
+** For non-root nodes, the first 2 bytes are left unused. |
+** |
+** 2. The next 2 bytes contain the number of entries currently |
+** stored in the node. |
+** |
+** 3. The remainder of the node contains the node entries. Each entry |
+** consists of a single 8-byte integer followed by an even number |
+** of 4-byte coordinates. For leaf nodes the integer is the rowid |
+** of a record. For internal nodes it is the node number of a |
+** child page. |
+*/ |
+ |
+#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_RTREE) |
+ |
+/* |
+** This file contains an implementation of a couple of different variants |
+** of the r-tree algorithm. See the README file for further details. The |
+** same data-structure is used for all, but the algorithms for insert and |
+** delete operations vary. The variants used are selected at compile time |
+** by defining the following symbols: |
+*/ |
+ |
+/* Either, both or none of the following may be set to activate |
+** r*tree variant algorithms. |
+*/ |
+#define VARIANT_RSTARTREE_CHOOSESUBTREE 0 |
+#define VARIANT_RSTARTREE_REINSERT 1 |
+ |
+/* |
+** Exactly one of the following must be set to 1. |
+*/ |
+#define VARIANT_GUTTMAN_QUADRATIC_SPLIT 0 |
+#define VARIANT_GUTTMAN_LINEAR_SPLIT 0 |
+#define VARIANT_RSTARTREE_SPLIT 1 |
+ |
+#define VARIANT_GUTTMAN_SPLIT \ |
+ (VARIANT_GUTTMAN_LINEAR_SPLIT||VARIANT_GUTTMAN_QUADRATIC_SPLIT) |
+ |
+#if VARIANT_GUTTMAN_QUADRATIC_SPLIT |
+ #define PickNext QuadraticPickNext |
+ #define PickSeeds QuadraticPickSeeds |
+ #define AssignCells splitNodeGuttman |
+#endif |
+#if VARIANT_GUTTMAN_LINEAR_SPLIT |
+ #define PickNext LinearPickNext |
+ #define PickSeeds LinearPickSeeds |
+ #define AssignCells splitNodeGuttman |
+#endif |
+#if VARIANT_RSTARTREE_SPLIT |
+ #define AssignCells splitNodeStartree |
+#endif |
+ |
+#if !defined(NDEBUG) && !defined(SQLITE_DEBUG) |
+# define NDEBUG 1 |
+#endif |
+ |
+#ifndef SQLITE_CORE |
+ #include "sqlite3ext.h" |
+ SQLITE_EXTENSION_INIT1 |
+#else |
+ #include "sqlite3.h" |
+#endif |
+ |
+#include <string.h> |
+#include <assert.h> |
+ |
+#ifndef SQLITE_AMALGAMATION |
+#include "sqlite3rtree.h" |
+typedef sqlite3_int64 i64; |
+typedef unsigned char u8; |
+typedef unsigned int u32; |
+#endif |
+ |
+/* The following macro is used to suppress compiler warnings. |
+*/ |
+#ifndef UNUSED_PARAMETER |
+# define UNUSED_PARAMETER(x) (void)(x) |
+#endif |
+ |
+typedef struct Rtree Rtree; |
+typedef struct RtreeCursor RtreeCursor; |
+typedef struct RtreeNode RtreeNode; |
+typedef struct RtreeCell RtreeCell; |
+typedef struct RtreeConstraint RtreeConstraint; |
+typedef struct RtreeMatchArg RtreeMatchArg; |
+typedef struct RtreeGeomCallback RtreeGeomCallback; |
+typedef union RtreeCoord RtreeCoord; |
+ |
+/* The rtree may have between 1 and RTREE_MAX_DIMENSIONS dimensions. */ |
+#define RTREE_MAX_DIMENSIONS 5 |
+ |
+/* Size of hash table Rtree.aHash. This hash table is not expected to |
+** ever contain very many entries, so a fixed number of buckets is |
+** used. |
+*/ |
+#define HASHSIZE 128 |
+ |
+/* |
+** An rtree virtual-table object. |
+*/ |
+struct Rtree { |
+ sqlite3_vtab base; |
+ sqlite3 *db; /* Host database connection */ |
+ int iNodeSize; /* Size in bytes of each node in the node table */ |
+ int nDim; /* Number of dimensions */ |
+ int nBytesPerCell; /* Bytes consumed per cell */ |
+ int iDepth; /* Current depth of the r-tree structure */ |
+ char *zDb; /* Name of database containing r-tree table */ |
+ char *zName; /* Name of r-tree table */ |
+ RtreeNode *aHash[HASHSIZE]; /* Hash table of in-memory nodes. */ |
+ int nBusy; /* Current number of users of this structure */ |
+ |
+ /* List of nodes removed during a CondenseTree operation. List is |
+ ** linked together via the pointer normally used for hash chains - |
+ ** RtreeNode.pNext. RtreeNode.iNode stores the depth of the sub-tree |
+ ** headed by the node (leaf nodes have RtreeNode.iNode==0). |
+ */ |
+ RtreeNode *pDeleted; |
+ int iReinsertHeight; /* Height of sub-trees Reinsert() has run on */ |
+ |
+ /* Statements to read/write/delete a record from xxx_node */ |
+ sqlite3_stmt *pReadNode; |
+ sqlite3_stmt *pWriteNode; |
+ sqlite3_stmt *pDeleteNode; |
+ |
+ /* Statements to read/write/delete a record from xxx_rowid */ |
+ sqlite3_stmt *pReadRowid; |
+ sqlite3_stmt *pWriteRowid; |
+ sqlite3_stmt *pDeleteRowid; |
+ |
+ /* Statements to read/write/delete a record from xxx_parent */ |
+ sqlite3_stmt *pReadParent; |
+ sqlite3_stmt *pWriteParent; |
+ sqlite3_stmt *pDeleteParent; |
+ |
+ int eCoordType; |
+}; |
+ |
+/* Possible values for eCoordType: */ |
+#define RTREE_COORD_REAL32 0 |
+#define RTREE_COORD_INT32 1 |
+ |
+/* |
+** The minimum number of cells allowed for a node is a third of the |
+** maximum. In Gutman's notation: |
+** |
+** m = M/3 |
+** |
+** If an R*-tree "Reinsert" operation is required, the same number of |
+** cells are removed from the overfull node and reinserted into the tree. |
+*/ |
+#define RTREE_MINCELLS(p) ((((p)->iNodeSize-4)/(p)->nBytesPerCell)/3) |
+#define RTREE_REINSERT(p) RTREE_MINCELLS(p) |
+#define RTREE_MAXCELLS 51 |
+ |
+/* |
+** The smallest possible node-size is (512-64)==448 bytes. And the largest |
+** supported cell size is 48 bytes (8 byte rowid + ten 4 byte coordinates). |
+** Therefore all non-root nodes must contain at least 3 entries. Since |
+** 2^40 is greater than 2^64, an r-tree structure always has a depth of |
+** 40 or less. |
+*/ |
+#define RTREE_MAX_DEPTH 40 |
+ |
+/* |
+** An rtree cursor object. |
+*/ |
+struct RtreeCursor { |
+ sqlite3_vtab_cursor base; |
+ RtreeNode *pNode; /* Node cursor is currently pointing at */ |
+ int iCell; /* Index of current cell in pNode */ |
+ int iStrategy; /* Copy of idxNum search parameter */ |
+ int nConstraint; /* Number of entries in aConstraint */ |
+ RtreeConstraint *aConstraint; /* Search constraints. */ |
+}; |
+ |
+union RtreeCoord { |
+ float f; |
+ int i; |
+}; |
+ |
+/* |
+** The argument is an RtreeCoord. Return the value stored within the RtreeCoord |
+** formatted as a double. This macro assumes that local variable pRtree points |
+** to the Rtree structure associated with the RtreeCoord. |
+*/ |
+#define DCOORD(coord) ( \ |
+ (pRtree->eCoordType==RTREE_COORD_REAL32) ? \ |
+ ((double)coord.f) : \ |
+ ((double)coord.i) \ |
+) |
+ |
+/* |
+** A search constraint. |
+*/ |
+struct RtreeConstraint { |
+ int iCoord; /* Index of constrained coordinate */ |
+ int op; /* Constraining operation */ |
+ double rValue; /* Constraint value. */ |
+ int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *); |
+ sqlite3_rtree_geometry *pGeom; /* Constraint callback argument for a MATCH */ |
+}; |
+ |
+/* Possible values for RtreeConstraint.op */ |
+#define RTREE_EQ 0x41 |
+#define RTREE_LE 0x42 |
+#define RTREE_LT 0x43 |
+#define RTREE_GE 0x44 |
+#define RTREE_GT 0x45 |
+#define RTREE_MATCH 0x46 |
+ |
+/* |
+** An rtree structure node. |
+*/ |
+struct RtreeNode { |
+ RtreeNode *pParent; /* Parent node */ |
+ i64 iNode; |
+ int nRef; |
+ int isDirty; |
+ u8 *zData; |
+ RtreeNode *pNext; /* Next node in this hash chain */ |
+}; |
+#define NCELL(pNode) readInt16(&(pNode)->zData[2]) |
+ |
+/* |
+** Structure to store a deserialized rtree record. |
+*/ |
+struct RtreeCell { |
+ i64 iRowid; |
+ RtreeCoord aCoord[RTREE_MAX_DIMENSIONS*2]; |
+}; |
+ |
+ |
+/* |
+** Value for the first field of every RtreeMatchArg object. The MATCH |
+** operator tests that the first field of a blob operand matches this |
+** value to avoid operating on invalid blobs (which could cause a segfault). |
+*/ |
+#define RTREE_GEOMETRY_MAGIC 0x891245AB |
+ |
+/* |
+** An instance of this structure must be supplied as a blob argument to |
+** the right-hand-side of an SQL MATCH operator used to constrain an |
+** r-tree query. |
+*/ |
+struct RtreeMatchArg { |
+ u32 magic; /* Always RTREE_GEOMETRY_MAGIC */ |
+ int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *); |
+ void *pContext; |
+ int nParam; |
+ double aParam[1]; |
+}; |
+ |
+/* |
+** When a geometry callback is created (see sqlite3_rtree_geometry_callback), |
+** a single instance of the following structure is allocated. It is used |
+** as the context for the user-function created by by s_r_g_c(). The object |
+** is eventually deleted by the destructor mechanism provided by |
+** sqlite3_create_function_v2() (which is called by s_r_g_c() to create |
+** the geometry callback function). |
+*/ |
+struct RtreeGeomCallback { |
+ int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *); |
+ void *pContext; |
+}; |
+ |
+#ifndef MAX |
+# define MAX(x,y) ((x) < (y) ? (y) : (x)) |
+#endif |
+#ifndef MIN |
+# define MIN(x,y) ((x) > (y) ? (y) : (x)) |
+#endif |
+ |
+/* |
+** Functions to deserialize a 16 bit integer, 32 bit real number and |
+** 64 bit integer. The deserialized value is returned. |
+*/ |
+static int readInt16(u8 *p){ |
+ return (p[0]<<8) + p[1]; |
+} |
+static void readCoord(u8 *p, RtreeCoord *pCoord){ |
+ u32 i = ( |
+ (((u32)p[0]) << 24) + |
+ (((u32)p[1]) << 16) + |
+ (((u32)p[2]) << 8) + |
+ (((u32)p[3]) << 0) |
+ ); |
+ *(u32 *)pCoord = i; |
+} |
+static i64 readInt64(u8 *p){ |
+ return ( |
+ (((i64)p[0]) << 56) + |
+ (((i64)p[1]) << 48) + |
+ (((i64)p[2]) << 40) + |
+ (((i64)p[3]) << 32) + |
+ (((i64)p[4]) << 24) + |
+ (((i64)p[5]) << 16) + |
+ (((i64)p[6]) << 8) + |
+ (((i64)p[7]) << 0) |
+ ); |
+} |
+ |
+/* |
+** Functions to serialize a 16 bit integer, 32 bit real number and |
+** 64 bit integer. The value returned is the number of bytes written |
+** to the argument buffer (always 2, 4 and 8 respectively). |
+*/ |
+static int writeInt16(u8 *p, int i){ |
+ p[0] = (i>> 8)&0xFF; |
+ p[1] = (i>> 0)&0xFF; |
+ return 2; |
+} |
+static int writeCoord(u8 *p, RtreeCoord *pCoord){ |
+ u32 i; |
+ assert( sizeof(RtreeCoord)==4 ); |
+ assert( sizeof(u32)==4 ); |
+ i = *(u32 *)pCoord; |
+ p[0] = (i>>24)&0xFF; |
+ p[1] = (i>>16)&0xFF; |
+ p[2] = (i>> 8)&0xFF; |
+ p[3] = (i>> 0)&0xFF; |
+ return 4; |
+} |
+static int writeInt64(u8 *p, i64 i){ |
+ p[0] = (i>>56)&0xFF; |
+ p[1] = (i>>48)&0xFF; |
+ p[2] = (i>>40)&0xFF; |
+ p[3] = (i>>32)&0xFF; |
+ p[4] = (i>>24)&0xFF; |
+ p[5] = (i>>16)&0xFF; |
+ p[6] = (i>> 8)&0xFF; |
+ p[7] = (i>> 0)&0xFF; |
+ return 8; |
+} |
+ |
+/* |
+** Increment the reference count of node p. |
+*/ |
+static void nodeReference(RtreeNode *p){ |
+ if( p ){ |
+ p->nRef++; |
+ } |
+} |
+ |
+/* |
+** Clear the content of node p (set all bytes to 0x00). |
+*/ |
+static void nodeZero(Rtree *pRtree, RtreeNode *p){ |
+ memset(&p->zData[2], 0, pRtree->iNodeSize-2); |
+ p->isDirty = 1; |
+} |
+ |
+/* |
+** Given a node number iNode, return the corresponding key to use |
+** in the Rtree.aHash table. |
+*/ |
+static int nodeHash(i64 iNode){ |
+ return ( |
+ (iNode>>56) ^ (iNode>>48) ^ (iNode>>40) ^ (iNode>>32) ^ |
+ (iNode>>24) ^ (iNode>>16) ^ (iNode>> 8) ^ (iNode>> 0) |
+ ) % HASHSIZE; |
+} |
+ |
+/* |
+** Search the node hash table for node iNode. If found, return a pointer |
+** to it. Otherwise, return 0. |
+*/ |
+static RtreeNode *nodeHashLookup(Rtree *pRtree, i64 iNode){ |
+ RtreeNode *p; |
+ for(p=pRtree->aHash[nodeHash(iNode)]; p && p->iNode!=iNode; p=p->pNext); |
+ return p; |
+} |
+ |
+/* |
+** Add node pNode to the node hash table. |
+*/ |
+static void nodeHashInsert(Rtree *pRtree, RtreeNode *pNode){ |
+ int iHash; |
+ assert( pNode->pNext==0 ); |
+ iHash = nodeHash(pNode->iNode); |
+ pNode->pNext = pRtree->aHash[iHash]; |
+ pRtree->aHash[iHash] = pNode; |
+} |
+ |
+/* |
+** Remove node pNode from the node hash table. |
+*/ |
+static void nodeHashDelete(Rtree *pRtree, RtreeNode *pNode){ |
+ RtreeNode **pp; |
+ if( pNode->iNode!=0 ){ |
+ pp = &pRtree->aHash[nodeHash(pNode->iNode)]; |
+ for( ; (*pp)!=pNode; pp = &(*pp)->pNext){ assert(*pp); } |
+ *pp = pNode->pNext; |
+ pNode->pNext = 0; |
+ } |
+} |
+ |
+/* |
+** Allocate and return new r-tree node. Initially, (RtreeNode.iNode==0), |
+** indicating that node has not yet been assigned a node number. It is |
+** assigned a node number when nodeWrite() is called to write the |
+** node contents out to the database. |
+*/ |
+static RtreeNode *nodeNew(Rtree *pRtree, RtreeNode *pParent){ |
+ RtreeNode *pNode; |
+ pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode) + pRtree->iNodeSize); |
+ if( pNode ){ |
+ memset(pNode, 0, sizeof(RtreeNode) + pRtree->iNodeSize); |
+ pNode->zData = (u8 *)&pNode[1]; |
+ pNode->nRef = 1; |
+ pNode->pParent = pParent; |
+ pNode->isDirty = 1; |
+ nodeReference(pParent); |
+ } |
+ return pNode; |
+} |
+ |
+/* |
+** Obtain a reference to an r-tree node. |
+*/ |
+static int |
+nodeAcquire( |
+ Rtree *pRtree, /* R-tree structure */ |
+ i64 iNode, /* Node number to load */ |
+ RtreeNode *pParent, /* Either the parent node or NULL */ |
+ RtreeNode **ppNode /* OUT: Acquired node */ |
+){ |
+ int rc; |
+ int rc2 = SQLITE_OK; |
+ RtreeNode *pNode; |
+ |
+ /* Check if the requested node is already in the hash table. If so, |
+ ** increase its reference count and return it. |
+ */ |
+ if( (pNode = nodeHashLookup(pRtree, iNode)) ){ |
+ assert( !pParent || !pNode->pParent || pNode->pParent==pParent ); |
+ if( pParent && !pNode->pParent ){ |
+ nodeReference(pParent); |
+ pNode->pParent = pParent; |
+ } |
+ pNode->nRef++; |
+ *ppNode = pNode; |
+ return SQLITE_OK; |
+ } |
+ |
+ sqlite3_bind_int64(pRtree->pReadNode, 1, iNode); |
+ rc = sqlite3_step(pRtree->pReadNode); |
+ if( rc==SQLITE_ROW ){ |
+ const u8 *zBlob = sqlite3_column_blob(pRtree->pReadNode, 0); |
+ if( pRtree->iNodeSize==sqlite3_column_bytes(pRtree->pReadNode, 0) ){ |
+ pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode)+pRtree->iNodeSize); |
+ if( !pNode ){ |
+ rc2 = SQLITE_NOMEM; |
+ }else{ |
+ pNode->pParent = pParent; |
+ pNode->zData = (u8 *)&pNode[1]; |
+ pNode->nRef = 1; |
+ pNode->iNode = iNode; |
+ pNode->isDirty = 0; |
+ pNode->pNext = 0; |
+ memcpy(pNode->zData, zBlob, pRtree->iNodeSize); |
+ nodeReference(pParent); |
+ } |
+ } |
+ } |
+ rc = sqlite3_reset(pRtree->pReadNode); |
+ if( rc==SQLITE_OK ) rc = rc2; |
+ |
+ /* If the root node was just loaded, set pRtree->iDepth to the height |
+ ** of the r-tree structure. A height of zero means all data is stored on |
+ ** the root node. A height of one means the children of the root node |
+ ** are the leaves, and so on. If the depth as specified on the root node |
+ ** is greater than RTREE_MAX_DEPTH, the r-tree structure must be corrupt. |
+ */ |
+ if( pNode && iNode==1 ){ |
+ pRtree->iDepth = readInt16(pNode->zData); |
+ if( pRtree->iDepth>RTREE_MAX_DEPTH ){ |
+ rc = SQLITE_CORRUPT; |
+ } |
+ } |
+ |
+ /* If no error has occurred so far, check if the "number of entries" |
+ ** field on the node is too large. If so, set the return code to |
+ ** SQLITE_CORRUPT. |
+ */ |
+ if( pNode && rc==SQLITE_OK ){ |
+ if( NCELL(pNode)>((pRtree->iNodeSize-4)/pRtree->nBytesPerCell) ){ |
+ rc = SQLITE_CORRUPT; |
+ } |
+ } |
+ |
+ if( rc==SQLITE_OK ){ |
+ if( pNode!=0 ){ |
+ nodeHashInsert(pRtree, pNode); |
+ }else{ |
+ rc = SQLITE_CORRUPT; |
+ } |
+ *ppNode = pNode; |
+ }else{ |
+ sqlite3_free(pNode); |
+ *ppNode = 0; |
+ } |
+ |
+ return rc; |
+} |
+ |
+/* |
+** Overwrite cell iCell of node pNode with the contents of pCell. |
+*/ |
+static void nodeOverwriteCell( |
+ Rtree *pRtree, |
+ RtreeNode *pNode, |
+ RtreeCell *pCell, |
+ int iCell |
+){ |
+ int ii; |
+ u8 *p = &pNode->zData[4 + pRtree->nBytesPerCell*iCell]; |
+ p += writeInt64(p, pCell->iRowid); |
+ for(ii=0; ii<(pRtree->nDim*2); ii++){ |
+ p += writeCoord(p, &pCell->aCoord[ii]); |
+ } |
+ pNode->isDirty = 1; |
+} |
+ |
+/* |
+** Remove cell the cell with index iCell from node pNode. |
+*/ |
+static void nodeDeleteCell(Rtree *pRtree, RtreeNode *pNode, int iCell){ |
+ u8 *pDst = &pNode->zData[4 + pRtree->nBytesPerCell*iCell]; |
+ u8 *pSrc = &pDst[pRtree->nBytesPerCell]; |
+ int nByte = (NCELL(pNode) - iCell - 1) * pRtree->nBytesPerCell; |
+ memmove(pDst, pSrc, nByte); |
+ writeInt16(&pNode->zData[2], NCELL(pNode)-1); |
+ pNode->isDirty = 1; |
+} |
+ |
+/* |
+** Insert the contents of cell pCell into node pNode. If the insert |
+** is successful, return SQLITE_OK. |
+** |
+** If there is not enough free space in pNode, return SQLITE_FULL. |
+*/ |
+static int |
+nodeInsertCell( |
+ Rtree *pRtree, |
+ RtreeNode *pNode, |
+ RtreeCell *pCell |
+){ |
+ int nCell; /* Current number of cells in pNode */ |
+ int nMaxCell; /* Maximum number of cells for pNode */ |
+ |
+ nMaxCell = (pRtree->iNodeSize-4)/pRtree->nBytesPerCell; |
+ nCell = NCELL(pNode); |
+ |
+ assert( nCell<=nMaxCell ); |
+ if( nCell<nMaxCell ){ |
+ nodeOverwriteCell(pRtree, pNode, pCell, nCell); |
+ writeInt16(&pNode->zData[2], nCell+1); |
+ pNode->isDirty = 1; |
+ } |
+ |
+ return (nCell==nMaxCell); |
+} |
+ |
+/* |
+** If the node is dirty, write it out to the database. |
+*/ |
+static int |
+nodeWrite(Rtree *pRtree, RtreeNode *pNode){ |
+ int rc = SQLITE_OK; |
+ if( pNode->isDirty ){ |
+ sqlite3_stmt *p = pRtree->pWriteNode; |
+ if( pNode->iNode ){ |
+ sqlite3_bind_int64(p, 1, pNode->iNode); |
+ }else{ |
+ sqlite3_bind_null(p, 1); |
+ } |
+ sqlite3_bind_blob(p, 2, pNode->zData, pRtree->iNodeSize, SQLITE_STATIC); |
+ sqlite3_step(p); |
+ pNode->isDirty = 0; |
+ rc = sqlite3_reset(p); |
+ if( pNode->iNode==0 && rc==SQLITE_OK ){ |
+ pNode->iNode = sqlite3_last_insert_rowid(pRtree->db); |
+ nodeHashInsert(pRtree, pNode); |
+ } |
+ } |
+ return rc; |
+} |
+ |
+/* |
+** Release a reference to a node. If the node is dirty and the reference |
+** count drops to zero, the node data is written to the database. |
+*/ |
+static int |
+nodeRelease(Rtree *pRtree, RtreeNode *pNode){ |
+ int rc = SQLITE_OK; |
+ if( pNode ){ |
+ assert( pNode->nRef>0 ); |
+ pNode->nRef--; |
+ if( pNode->nRef==0 ){ |
+ if( pNode->iNode==1 ){ |
+ pRtree->iDepth = -1; |
+ } |
+ if( pNode->pParent ){ |
+ rc = nodeRelease(pRtree, pNode->pParent); |
+ } |
+ if( rc==SQLITE_OK ){ |
+ rc = nodeWrite(pRtree, pNode); |
+ } |
+ nodeHashDelete(pRtree, pNode); |
+ sqlite3_free(pNode); |
+ } |
+ } |
+ return rc; |
+} |
+ |
+/* |
+** Return the 64-bit integer value associated with cell iCell of |
+** node pNode. If pNode is a leaf node, this is a rowid. If it is |
+** an internal node, then the 64-bit integer is a child page number. |
+*/ |
+static i64 nodeGetRowid( |
+ Rtree *pRtree, |
+ RtreeNode *pNode, |
+ int iCell |
+){ |
+ assert( iCell<NCELL(pNode) ); |
+ return readInt64(&pNode->zData[4 + pRtree->nBytesPerCell*iCell]); |
+} |
+ |
+/* |
+** Return coordinate iCoord from cell iCell in node pNode. |
+*/ |
+static void nodeGetCoord( |
+ Rtree *pRtree, |
+ RtreeNode *pNode, |
+ int iCell, |
+ int iCoord, |
+ RtreeCoord *pCoord /* Space to write result to */ |
+){ |
+ readCoord(&pNode->zData[12 + pRtree->nBytesPerCell*iCell + 4*iCoord], pCoord); |
+} |
+ |
+/* |
+** Deserialize cell iCell of node pNode. Populate the structure pointed |
+** to by pCell with the results. |
+*/ |
+static void nodeGetCell( |
+ Rtree *pRtree, |
+ RtreeNode *pNode, |
+ int iCell, |
+ RtreeCell *pCell |
+){ |
+ int ii; |
+ pCell->iRowid = nodeGetRowid(pRtree, pNode, iCell); |
+ for(ii=0; ii<pRtree->nDim*2; ii++){ |
+ nodeGetCoord(pRtree, pNode, iCell, ii, &pCell->aCoord[ii]); |
+ } |
+} |
+ |
+ |
+/* Forward declaration for the function that does the work of |
+** the virtual table module xCreate() and xConnect() methods. |
+*/ |
+static int rtreeInit( |
+ sqlite3 *, void *, int, const char *const*, sqlite3_vtab **, char **, int |
+); |
+ |
+/* |
+** Rtree virtual table module xCreate method. |
+*/ |
+static int rtreeCreate( |
+ sqlite3 *db, |
+ void *pAux, |
+ int argc, const char *const*argv, |
+ sqlite3_vtab **ppVtab, |
+ char **pzErr |
+){ |
+ return rtreeInit(db, pAux, argc, argv, ppVtab, pzErr, 1); |
+} |
+ |
+/* |
+** Rtree virtual table module xConnect method. |
+*/ |
+static int rtreeConnect( |
+ sqlite3 *db, |
+ void *pAux, |
+ int argc, const char *const*argv, |
+ sqlite3_vtab **ppVtab, |
+ char **pzErr |
+){ |
+ return rtreeInit(db, pAux, argc, argv, ppVtab, pzErr, 0); |
+} |
+ |
+/* |
+** Increment the r-tree reference count. |
+*/ |
+static void rtreeReference(Rtree *pRtree){ |
+ pRtree->nBusy++; |
+} |
+ |
+/* |
+** Decrement the r-tree reference count. When the reference count reaches |
+** zero the structure is deleted. |
+*/ |
+static void rtreeRelease(Rtree *pRtree){ |
+ pRtree->nBusy--; |
+ if( pRtree->nBusy==0 ){ |
+ sqlite3_finalize(pRtree->pReadNode); |
+ sqlite3_finalize(pRtree->pWriteNode); |
+ sqlite3_finalize(pRtree->pDeleteNode); |
+ sqlite3_finalize(pRtree->pReadRowid); |
+ sqlite3_finalize(pRtree->pWriteRowid); |
+ sqlite3_finalize(pRtree->pDeleteRowid); |
+ sqlite3_finalize(pRtree->pReadParent); |
+ sqlite3_finalize(pRtree->pWriteParent); |
+ sqlite3_finalize(pRtree->pDeleteParent); |
+ sqlite3_free(pRtree); |
+ } |
+} |
+ |
+/* |
+** Rtree virtual table module xDisconnect method. |
+*/ |
+static int rtreeDisconnect(sqlite3_vtab *pVtab){ |
+ rtreeRelease((Rtree *)pVtab); |
+ return SQLITE_OK; |
+} |
+ |
+/* |
+** Rtree virtual table module xDestroy method. |
+*/ |
+static int rtreeDestroy(sqlite3_vtab *pVtab){ |
+ Rtree *pRtree = (Rtree *)pVtab; |
+ int rc; |
+ char *zCreate = sqlite3_mprintf( |
+ "DROP TABLE '%q'.'%q_node';" |
+ "DROP TABLE '%q'.'%q_rowid';" |
+ "DROP TABLE '%q'.'%q_parent';", |
+ pRtree->zDb, pRtree->zName, |
+ pRtree->zDb, pRtree->zName, |
+ pRtree->zDb, pRtree->zName |
+ ); |
+ if( !zCreate ){ |
+ rc = SQLITE_NOMEM; |
+ }else{ |
+ rc = sqlite3_exec(pRtree->db, zCreate, 0, 0, 0); |
+ sqlite3_free(zCreate); |
+ } |
+ if( rc==SQLITE_OK ){ |
+ rtreeRelease(pRtree); |
+ } |
+ |
+ return rc; |
+} |
+ |
+/* |
+** Rtree virtual table module xOpen method. |
+*/ |
+static int rtreeOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){ |
+ int rc = SQLITE_NOMEM; |
+ RtreeCursor *pCsr; |
+ |
+ pCsr = (RtreeCursor *)sqlite3_malloc(sizeof(RtreeCursor)); |
+ if( pCsr ){ |
+ memset(pCsr, 0, sizeof(RtreeCursor)); |
+ pCsr->base.pVtab = pVTab; |
+ rc = SQLITE_OK; |
+ } |
+ *ppCursor = (sqlite3_vtab_cursor *)pCsr; |
+ |
+ return rc; |
+} |
+ |
+ |
+/* |
+** Free the RtreeCursor.aConstraint[] array and its contents. |
+*/ |
+static void freeCursorConstraints(RtreeCursor *pCsr){ |
+ if( pCsr->aConstraint ){ |
+ int i; /* Used to iterate through constraint array */ |
+ for(i=0; i<pCsr->nConstraint; i++){ |
+ sqlite3_rtree_geometry *pGeom = pCsr->aConstraint[i].pGeom; |
+ if( pGeom ){ |
+ if( pGeom->xDelUser ) pGeom->xDelUser(pGeom->pUser); |
+ sqlite3_free(pGeom); |
+ } |
+ } |
+ sqlite3_free(pCsr->aConstraint); |
+ pCsr->aConstraint = 0; |
+ } |
+} |
+ |
+/* |
+** Rtree virtual table module xClose method. |
+*/ |
+static int rtreeClose(sqlite3_vtab_cursor *cur){ |
+ Rtree *pRtree = (Rtree *)(cur->pVtab); |
+ int rc; |
+ RtreeCursor *pCsr = (RtreeCursor *)cur; |
+ freeCursorConstraints(pCsr); |
+ rc = nodeRelease(pRtree, pCsr->pNode); |
+ sqlite3_free(pCsr); |
+ return rc; |
+} |
+ |
+/* |
+** Rtree virtual table module xEof method. |
+** |
+** Return non-zero if the cursor does not currently point to a valid |
+** record (i.e if the scan has finished), or zero otherwise. |
+*/ |
+static int rtreeEof(sqlite3_vtab_cursor *cur){ |
+ RtreeCursor *pCsr = (RtreeCursor *)cur; |
+ return (pCsr->pNode==0); |
+} |
+ |
+/* |
+** The r-tree constraint passed as the second argument to this function is |
+** guaranteed to be a MATCH constraint. |
+*/ |
+static int testRtreeGeom( |
+ Rtree *pRtree, /* R-Tree object */ |
+ RtreeConstraint *pConstraint, /* MATCH constraint to test */ |
+ RtreeCell *pCell, /* Cell to test */ |
+ int *pbRes /* OUT: Test result */ |
+){ |
+ int i; |
+ double aCoord[RTREE_MAX_DIMENSIONS*2]; |
+ int nCoord = pRtree->nDim*2; |
+ |
+ assert( pConstraint->op==RTREE_MATCH ); |
+ assert( pConstraint->pGeom ); |
+ |
+ for(i=0; i<nCoord; i++){ |
+ aCoord[i] = DCOORD(pCell->aCoord[i]); |
+ } |
+ return pConstraint->xGeom(pConstraint->pGeom, nCoord, aCoord, pbRes); |
+} |
+ |
+/* |
+** Cursor pCursor currently points to a cell in a non-leaf page. |
+** Set *pbEof to true if the sub-tree headed by the cell is filtered |
+** (excluded) by the constraints in the pCursor->aConstraint[] |
+** array, or false otherwise. |
+** |
+** Return SQLITE_OK if successful or an SQLite error code if an error |
+** occurs within a geometry callback. |
+*/ |
+static int testRtreeCell(Rtree *pRtree, RtreeCursor *pCursor, int *pbEof){ |
+ RtreeCell cell; |
+ int ii; |
+ int bRes = 0; |
+ int rc = SQLITE_OK; |
+ |
+ nodeGetCell(pRtree, pCursor->pNode, pCursor->iCell, &cell); |
+ for(ii=0; bRes==0 && ii<pCursor->nConstraint; ii++){ |
+ RtreeConstraint *p = &pCursor->aConstraint[ii]; |
+ double cell_min = DCOORD(cell.aCoord[(p->iCoord>>1)*2]); |
+ double cell_max = DCOORD(cell.aCoord[(p->iCoord>>1)*2+1]); |
+ |
+ assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE |
+ || p->op==RTREE_GT || p->op==RTREE_EQ || p->op==RTREE_MATCH |
+ ); |
+ |
+ switch( p->op ){ |
+ case RTREE_LE: case RTREE_LT: |
+ bRes = p->rValue<cell_min; |
+ break; |
+ |
+ case RTREE_GE: case RTREE_GT: |
+ bRes = p->rValue>cell_max; |
+ break; |
+ |
+ case RTREE_EQ: |
+ bRes = (p->rValue>cell_max || p->rValue<cell_min); |
+ break; |
+ |
+ default: { |
+ assert( p->op==RTREE_MATCH ); |
+ rc = testRtreeGeom(pRtree, p, &cell, &bRes); |
+ bRes = !bRes; |
+ break; |
+ } |
+ } |
+ } |
+ |
+ *pbEof = bRes; |
+ return rc; |
+} |
+ |
+/* |
+** Test if the cell that cursor pCursor currently points to |
+** would be filtered (excluded) by the constraints in the |
+** pCursor->aConstraint[] array. If so, set *pbEof to true before |
+** returning. If the cell is not filtered (excluded) by the constraints, |
+** set pbEof to zero. |
+** |
+** Return SQLITE_OK if successful or an SQLite error code if an error |
+** occurs within a geometry callback. |
+** |
+** This function assumes that the cell is part of a leaf node. |
+*/ |
+static int testRtreeEntry(Rtree *pRtree, RtreeCursor *pCursor, int *pbEof){ |
+ RtreeCell cell; |
+ int ii; |
+ *pbEof = 0; |
+ |
+ nodeGetCell(pRtree, pCursor->pNode, pCursor->iCell, &cell); |
+ for(ii=0; ii<pCursor->nConstraint; ii++){ |
+ RtreeConstraint *p = &pCursor->aConstraint[ii]; |
+ double coord = DCOORD(cell.aCoord[p->iCoord]); |
+ int res; |
+ assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE |
+ || p->op==RTREE_GT || p->op==RTREE_EQ || p->op==RTREE_MATCH |
+ ); |
+ switch( p->op ){ |
+ case RTREE_LE: res = (coord<=p->rValue); break; |
+ case RTREE_LT: res = (coord<p->rValue); break; |
+ case RTREE_GE: res = (coord>=p->rValue); break; |
+ case RTREE_GT: res = (coord>p->rValue); break; |
+ case RTREE_EQ: res = (coord==p->rValue); break; |
+ default: { |
+ int rc; |
+ assert( p->op==RTREE_MATCH ); |
+ rc = testRtreeGeom(pRtree, p, &cell, &res); |
+ if( rc!=SQLITE_OK ){ |
+ return rc; |
+ } |
+ break; |
+ } |
+ } |
+ |
+ if( !res ){ |
+ *pbEof = 1; |
+ return SQLITE_OK; |
+ } |
+ } |
+ |
+ return SQLITE_OK; |
+} |
+ |
+/* |
+** Cursor pCursor currently points at a node that heads a sub-tree of |
+** height iHeight (if iHeight==0, then the node is a leaf). Descend |
+** to point to the left-most cell of the sub-tree that matches the |
+** configured constraints. |
+*/ |
+static int descendToCell( |
+ Rtree *pRtree, |
+ RtreeCursor *pCursor, |
+ int iHeight, |
+ int *pEof /* OUT: Set to true if cannot descend */ |
+){ |
+ int isEof; |
+ int rc; |
+ int ii; |
+ RtreeNode *pChild; |
+ sqlite3_int64 iRowid; |
+ |
+ RtreeNode *pSavedNode = pCursor->pNode; |
+ int iSavedCell = pCursor->iCell; |
+ |
+ assert( iHeight>=0 ); |
+ |
+ if( iHeight==0 ){ |
+ rc = testRtreeEntry(pRtree, pCursor, &isEof); |
+ }else{ |
+ rc = testRtreeCell(pRtree, pCursor, &isEof); |
+ } |
+ if( rc!=SQLITE_OK || isEof || iHeight==0 ){ |
+ goto descend_to_cell_out; |
+ } |
+ |
+ iRowid = nodeGetRowid(pRtree, pCursor->pNode, pCursor->iCell); |
+ rc = nodeAcquire(pRtree, iRowid, pCursor->pNode, &pChild); |
+ if( rc!=SQLITE_OK ){ |
+ goto descend_to_cell_out; |
+ } |
+ |
+ nodeRelease(pRtree, pCursor->pNode); |
+ pCursor->pNode = pChild; |
+ isEof = 1; |
+ for(ii=0; isEof && ii<NCELL(pChild); ii++){ |
+ pCursor->iCell = ii; |
+ rc = descendToCell(pRtree, pCursor, iHeight-1, &isEof); |
+ if( rc!=SQLITE_OK ){ |
+ goto descend_to_cell_out; |
+ } |
+ } |
+ |
+ if( isEof ){ |
+ assert( pCursor->pNode==pChild ); |
+ nodeReference(pSavedNode); |
+ nodeRelease(pRtree, pChild); |
+ pCursor->pNode = pSavedNode; |
+ pCursor->iCell = iSavedCell; |
+ } |
+ |
+descend_to_cell_out: |
+ *pEof = isEof; |
+ return rc; |
+} |
+ |
+/* |
+** One of the cells in node pNode is guaranteed to have a 64-bit |
+** integer value equal to iRowid. Return the index of this cell. |
+*/ |
+static int nodeRowidIndex( |
+ Rtree *pRtree, |
+ RtreeNode *pNode, |
+ i64 iRowid, |
+ int *piIndex |
+){ |
+ int ii; |
+ int nCell = NCELL(pNode); |
+ for(ii=0; ii<nCell; ii++){ |
+ if( nodeGetRowid(pRtree, pNode, ii)==iRowid ){ |
+ *piIndex = ii; |
+ return SQLITE_OK; |
+ } |
+ } |
+ return SQLITE_CORRUPT; |
+} |
+ |
+/* |
+** Return the index of the cell containing a pointer to node pNode |
+** in its parent. If pNode is the root node, return -1. |
+*/ |
+static int nodeParentIndex(Rtree *pRtree, RtreeNode *pNode, int *piIndex){ |
+ RtreeNode *pParent = pNode->pParent; |
+ if( pParent ){ |
+ return nodeRowidIndex(pRtree, pParent, pNode->iNode, piIndex); |
+ } |
+ *piIndex = -1; |
+ return SQLITE_OK; |
+} |
+ |
+/* |
+** Rtree virtual table module xNext method. |
+*/ |
+static int rtreeNext(sqlite3_vtab_cursor *pVtabCursor){ |
+ Rtree *pRtree = (Rtree *)(pVtabCursor->pVtab); |
+ RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor; |
+ int rc = SQLITE_OK; |
+ |
+ /* RtreeCursor.pNode must not be NULL. If is is NULL, then this cursor is |
+ ** already at EOF. It is against the rules to call the xNext() method of |
+ ** a cursor that has already reached EOF. |
+ */ |
+ assert( pCsr->pNode ); |
+ |
+ if( pCsr->iStrategy==1 ){ |
+ /* This "scan" is a direct lookup by rowid. There is no next entry. */ |
+ nodeRelease(pRtree, pCsr->pNode); |
+ pCsr->pNode = 0; |
+ }else{ |
+ /* Move to the next entry that matches the configured constraints. */ |
+ int iHeight = 0; |
+ while( pCsr->pNode ){ |
+ RtreeNode *pNode = pCsr->pNode; |
+ int nCell = NCELL(pNode); |
+ for(pCsr->iCell++; pCsr->iCell<nCell; pCsr->iCell++){ |
+ int isEof; |
+ rc = descendToCell(pRtree, pCsr, iHeight, &isEof); |
+ if( rc!=SQLITE_OK || !isEof ){ |
+ return rc; |
+ } |
+ } |
+ pCsr->pNode = pNode->pParent; |
+ rc = nodeParentIndex(pRtree, pNode, &pCsr->iCell); |
+ if( rc!=SQLITE_OK ){ |
+ return rc; |
+ } |
+ nodeReference(pCsr->pNode); |
+ nodeRelease(pRtree, pNode); |
+ iHeight++; |
+ } |
+ } |
+ |
+ return rc; |
+} |
+ |
+/* |
+** Rtree virtual table module xRowid method. |
+*/ |
+static int rtreeRowid(sqlite3_vtab_cursor *pVtabCursor, sqlite_int64 *pRowid){ |
+ Rtree *pRtree = (Rtree *)pVtabCursor->pVtab; |
+ RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor; |
+ |
+ assert(pCsr->pNode); |
+ *pRowid = nodeGetRowid(pRtree, pCsr->pNode, pCsr->iCell); |
+ |
+ return SQLITE_OK; |
+} |
+ |
+/* |
+** Rtree virtual table module xColumn method. |
+*/ |
+static int rtreeColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){ |
+ Rtree *pRtree = (Rtree *)cur->pVtab; |
+ RtreeCursor *pCsr = (RtreeCursor *)cur; |
+ |
+ if( i==0 ){ |
+ i64 iRowid = nodeGetRowid(pRtree, pCsr->pNode, pCsr->iCell); |
+ sqlite3_result_int64(ctx, iRowid); |
+ }else{ |
+ RtreeCoord c; |
+ nodeGetCoord(pRtree, pCsr->pNode, pCsr->iCell, i-1, &c); |
+ if( pRtree->eCoordType==RTREE_COORD_REAL32 ){ |
+ sqlite3_result_double(ctx, c.f); |
+ }else{ |
+ assert( pRtree->eCoordType==RTREE_COORD_INT32 ); |
+ sqlite3_result_int(ctx, c.i); |
+ } |
+ } |
+ |
+ return SQLITE_OK; |
+} |
+ |
+/* |
+** Use nodeAcquire() to obtain the leaf node containing the record with |
+** rowid iRowid. If successful, set *ppLeaf to point to the node and |
+** return SQLITE_OK. If there is no such record in the table, set |
+** *ppLeaf to 0 and return SQLITE_OK. If an error occurs, set *ppLeaf |
+** to zero and return an SQLite error code. |
+*/ |
+static int findLeafNode(Rtree *pRtree, i64 iRowid, RtreeNode **ppLeaf){ |
+ int rc; |
+ *ppLeaf = 0; |
+ sqlite3_bind_int64(pRtree->pReadRowid, 1, iRowid); |
+ if( sqlite3_step(pRtree->pReadRowid)==SQLITE_ROW ){ |
+ i64 iNode = sqlite3_column_int64(pRtree->pReadRowid, 0); |
+ rc = nodeAcquire(pRtree, iNode, 0, ppLeaf); |
+ sqlite3_reset(pRtree->pReadRowid); |
+ }else{ |
+ rc = sqlite3_reset(pRtree->pReadRowid); |
+ } |
+ return rc; |
+} |
+ |
+/* |
+** This function is called to configure the RtreeConstraint object passed |
+** as the second argument for a MATCH constraint. The value passed as the |
+** first argument to this function is the right-hand operand to the MATCH |
+** operator. |
+*/ |
+static int deserializeGeometry(sqlite3_value *pValue, RtreeConstraint *pCons){ |
+ RtreeMatchArg *p; |
+ sqlite3_rtree_geometry *pGeom; |
+ int nBlob; |
+ |
+ /* Check that value is actually a blob. */ |
+ if( !sqlite3_value_type(pValue)==SQLITE_BLOB ) return SQLITE_ERROR; |
+ |
+ /* Check that the blob is roughly the right size. */ |
+ nBlob = sqlite3_value_bytes(pValue); |
+ if( nBlob<(int)sizeof(RtreeMatchArg) |
+ || ((nBlob-sizeof(RtreeMatchArg))%sizeof(double))!=0 |
+ ){ |
+ return SQLITE_ERROR; |
+ } |
+ |
+ pGeom = (sqlite3_rtree_geometry *)sqlite3_malloc( |
+ sizeof(sqlite3_rtree_geometry) + nBlob |
+ ); |
+ if( !pGeom ) return SQLITE_NOMEM; |
+ memset(pGeom, 0, sizeof(sqlite3_rtree_geometry)); |
+ p = (RtreeMatchArg *)&pGeom[1]; |
+ |
+ memcpy(p, sqlite3_value_blob(pValue), nBlob); |
+ if( p->magic!=RTREE_GEOMETRY_MAGIC |
+ || nBlob!=(int)(sizeof(RtreeMatchArg) + (p->nParam-1)*sizeof(double)) |
+ ){ |
+ sqlite3_free(pGeom); |
+ return SQLITE_ERROR; |
+ } |
+ |
+ pGeom->pContext = p->pContext; |
+ pGeom->nParam = p->nParam; |
+ pGeom->aParam = p->aParam; |
+ |
+ pCons->xGeom = p->xGeom; |
+ pCons->pGeom = pGeom; |
+ return SQLITE_OK; |
+} |
+ |
+/* |
+** Rtree virtual table module xFilter method. |
+*/ |
+static int rtreeFilter( |
+ sqlite3_vtab_cursor *pVtabCursor, |
+ int idxNum, const char *idxStr, |
+ int argc, sqlite3_value **argv |
+){ |
+ Rtree *pRtree = (Rtree *)pVtabCursor->pVtab; |
+ RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor; |
+ |
+ RtreeNode *pRoot = 0; |
+ int ii; |
+ int rc = SQLITE_OK; |
+ |
+ rtreeReference(pRtree); |
+ |
+ freeCursorConstraints(pCsr); |
+ pCsr->iStrategy = idxNum; |
+ |
+ if( idxNum==1 ){ |
+ /* Special case - lookup by rowid. */ |
+ RtreeNode *pLeaf; /* Leaf on which the required cell resides */ |
+ i64 iRowid = sqlite3_value_int64(argv[0]); |
+ rc = findLeafNode(pRtree, iRowid, &pLeaf); |
+ pCsr->pNode = pLeaf; |
+ if( pLeaf ){ |
+ assert( rc==SQLITE_OK ); |
+ rc = nodeRowidIndex(pRtree, pLeaf, iRowid, &pCsr->iCell); |
+ } |
+ }else{ |
+ /* Normal case - r-tree scan. Set up the RtreeCursor.aConstraint array |
+ ** with the configured constraints. |
+ */ |
+ if( argc>0 ){ |
+ pCsr->aConstraint = sqlite3_malloc(sizeof(RtreeConstraint)*argc); |
+ pCsr->nConstraint = argc; |
+ if( !pCsr->aConstraint ){ |
+ rc = SQLITE_NOMEM; |
+ }else{ |
+ memset(pCsr->aConstraint, 0, sizeof(RtreeConstraint)*argc); |
+ assert( (idxStr==0 && argc==0) || (int)strlen(idxStr)==argc*2 ); |
+ for(ii=0; ii<argc; ii++){ |
+ RtreeConstraint *p = &pCsr->aConstraint[ii]; |
+ p->op = idxStr[ii*2]; |
+ p->iCoord = idxStr[ii*2+1]-'a'; |
+ if( p->op==RTREE_MATCH ){ |
+ /* A MATCH operator. The right-hand-side must be a blob that |
+ ** can be cast into an RtreeMatchArg object. One created using |
+ ** an sqlite3_rtree_geometry_callback() SQL user function. |
+ */ |
+ rc = deserializeGeometry(argv[ii], p); |
+ if( rc!=SQLITE_OK ){ |
+ break; |
+ } |
+ }else{ |
+ p->rValue = sqlite3_value_double(argv[ii]); |
+ } |
+ } |
+ } |
+ } |
+ |
+ if( rc==SQLITE_OK ){ |
+ pCsr->pNode = 0; |
+ rc = nodeAcquire(pRtree, 1, 0, &pRoot); |
+ } |
+ if( rc==SQLITE_OK ){ |
+ int isEof = 1; |
+ int nCell = NCELL(pRoot); |
+ pCsr->pNode = pRoot; |
+ for(pCsr->iCell=0; rc==SQLITE_OK && pCsr->iCell<nCell; pCsr->iCell++){ |
+ assert( pCsr->pNode==pRoot ); |
+ rc = descendToCell(pRtree, pCsr, pRtree->iDepth, &isEof); |
+ if( !isEof ){ |
+ break; |
+ } |
+ } |
+ if( rc==SQLITE_OK && isEof ){ |
+ assert( pCsr->pNode==pRoot ); |
+ nodeRelease(pRtree, pRoot); |
+ pCsr->pNode = 0; |
+ } |
+ assert( rc!=SQLITE_OK || !pCsr->pNode || pCsr->iCell<NCELL(pCsr->pNode) ); |
+ } |
+ } |
+ |
+ rtreeRelease(pRtree); |
+ return rc; |
+} |
+ |
+/* |
+** Rtree virtual table module xBestIndex method. There are three |
+** table scan strategies to choose from (in order from most to |
+** least desirable): |
+** |
+** idxNum idxStr Strategy |
+** ------------------------------------------------ |
+** 1 Unused Direct lookup by rowid. |
+** 2 See below R-tree query or full-table scan. |
+** ------------------------------------------------ |
+** |
+** If strategy 1 is used, then idxStr is not meaningful. If strategy |
+** 2 is used, idxStr is formatted to contain 2 bytes for each |
+** constraint used. The first two bytes of idxStr correspond to |
+** the constraint in sqlite3_index_info.aConstraintUsage[] with |
+** (argvIndex==1) etc. |
+** |
+** The first of each pair of bytes in idxStr identifies the constraint |
+** operator as follows: |
+** |
+** Operator Byte Value |
+** ---------------------- |
+** = 0x41 ('A') |
+** <= 0x42 ('B') |
+** < 0x43 ('C') |
+** >= 0x44 ('D') |
+** > 0x45 ('E') |
+** MATCH 0x46 ('F') |
+** ---------------------- |
+** |
+** The second of each pair of bytes identifies the coordinate column |
+** to which the constraint applies. The leftmost coordinate column |
+** is 'a', the second from the left 'b' etc. |
+*/ |
+static int rtreeBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){ |
+ int rc = SQLITE_OK; |
+ int ii; |
+ |
+ int iIdx = 0; |
+ char zIdxStr[RTREE_MAX_DIMENSIONS*8+1]; |
+ memset(zIdxStr, 0, sizeof(zIdxStr)); |
+ UNUSED_PARAMETER(tab); |
+ |
+ assert( pIdxInfo->idxStr==0 ); |
+ for(ii=0; ii<pIdxInfo->nConstraint && iIdx<(int)(sizeof(zIdxStr)-1); ii++){ |
+ struct sqlite3_index_constraint *p = &pIdxInfo->aConstraint[ii]; |
+ |
+ if( p->usable && p->iColumn==0 && p->op==SQLITE_INDEX_CONSTRAINT_EQ ){ |
+ /* We have an equality constraint on the rowid. Use strategy 1. */ |
+ int jj; |
+ for(jj=0; jj<ii; jj++){ |
+ pIdxInfo->aConstraintUsage[jj].argvIndex = 0; |
+ pIdxInfo->aConstraintUsage[jj].omit = 0; |
+ } |
+ pIdxInfo->idxNum = 1; |
+ pIdxInfo->aConstraintUsage[ii].argvIndex = 1; |
+ pIdxInfo->aConstraintUsage[jj].omit = 1; |
+ |
+ /* This strategy involves a two rowid lookups on an B-Tree structures |
+ ** and then a linear search of an R-Tree node. This should be |
+ ** considered almost as quick as a direct rowid lookup (for which |
+ ** sqlite uses an internal cost of 0.0). |
+ */ |
+ pIdxInfo->estimatedCost = 10.0; |
+ return SQLITE_OK; |
+ } |
+ |
+ if( p->usable && (p->iColumn>0 || p->op==SQLITE_INDEX_CONSTRAINT_MATCH) ){ |
+ u8 op; |
+ switch( p->op ){ |
+ case SQLITE_INDEX_CONSTRAINT_EQ: op = RTREE_EQ; break; |
+ case SQLITE_INDEX_CONSTRAINT_GT: op = RTREE_GT; break; |
+ case SQLITE_INDEX_CONSTRAINT_LE: op = RTREE_LE; break; |
+ case SQLITE_INDEX_CONSTRAINT_LT: op = RTREE_LT; break; |
+ case SQLITE_INDEX_CONSTRAINT_GE: op = RTREE_GE; break; |
+ default: |
+ assert( p->op==SQLITE_INDEX_CONSTRAINT_MATCH ); |
+ op = RTREE_MATCH; |
+ break; |
+ } |
+ zIdxStr[iIdx++] = op; |
+ zIdxStr[iIdx++] = p->iColumn - 1 + 'a'; |
+ pIdxInfo->aConstraintUsage[ii].argvIndex = (iIdx/2); |
+ pIdxInfo->aConstraintUsage[ii].omit = 1; |
+ } |
+ } |
+ |
+ pIdxInfo->idxNum = 2; |
+ pIdxInfo->needToFreeIdxStr = 1; |
+ if( iIdx>0 && 0==(pIdxInfo->idxStr = sqlite3_mprintf("%s", zIdxStr)) ){ |
+ return SQLITE_NOMEM; |
+ } |
+ assert( iIdx>=0 ); |
+ pIdxInfo->estimatedCost = (2000000.0 / (double)(iIdx + 1)); |
+ return rc; |
+} |
+ |
+/* |
+** Return the N-dimensional volumn of the cell stored in *p. |
+*/ |
+static float cellArea(Rtree *pRtree, RtreeCell *p){ |
+ float area = 1.0; |
+ int ii; |
+ for(ii=0; ii<(pRtree->nDim*2); ii+=2){ |
+ area = area * (DCOORD(p->aCoord[ii+1]) - DCOORD(p->aCoord[ii])); |
+ } |
+ return area; |
+} |
+ |
+/* |
+** Return the margin length of cell p. The margin length is the sum |
+** of the objects size in each dimension. |
+*/ |
+static float cellMargin(Rtree *pRtree, RtreeCell *p){ |
+ float margin = 0.0; |
+ int ii; |
+ for(ii=0; ii<(pRtree->nDim*2); ii+=2){ |
+ margin += (DCOORD(p->aCoord[ii+1]) - DCOORD(p->aCoord[ii])); |
+ } |
+ return margin; |
+} |
+ |
+/* |
+** Store the union of cells p1 and p2 in p1. |
+*/ |
+static void cellUnion(Rtree *pRtree, RtreeCell *p1, RtreeCell *p2){ |
+ int ii; |
+ if( pRtree->eCoordType==RTREE_COORD_REAL32 ){ |
+ for(ii=0; ii<(pRtree->nDim*2); ii+=2){ |
+ p1->aCoord[ii].f = MIN(p1->aCoord[ii].f, p2->aCoord[ii].f); |
+ p1->aCoord[ii+1].f = MAX(p1->aCoord[ii+1].f, p2->aCoord[ii+1].f); |
+ } |
+ }else{ |
+ for(ii=0; ii<(pRtree->nDim*2); ii+=2){ |
+ p1->aCoord[ii].i = MIN(p1->aCoord[ii].i, p2->aCoord[ii].i); |
+ p1->aCoord[ii+1].i = MAX(p1->aCoord[ii+1].i, p2->aCoord[ii+1].i); |
+ } |
+ } |
+} |
+ |
+/* |
+** Return true if the area covered by p2 is a subset of the area covered |
+** by p1. False otherwise. |
+*/ |
+static int cellContains(Rtree *pRtree, RtreeCell *p1, RtreeCell *p2){ |
+ int ii; |
+ int isInt = (pRtree->eCoordType==RTREE_COORD_INT32); |
+ for(ii=0; ii<(pRtree->nDim*2); ii+=2){ |
+ RtreeCoord *a1 = &p1->aCoord[ii]; |
+ RtreeCoord *a2 = &p2->aCoord[ii]; |
+ if( (!isInt && (a2[0].f<a1[0].f || a2[1].f>a1[1].f)) |
+ || ( isInt && (a2[0].i<a1[0].i || a2[1].i>a1[1].i)) |
+ ){ |
+ return 0; |
+ } |
+ } |
+ return 1; |
+} |
+ |
+/* |
+** Return the amount cell p would grow by if it were unioned with pCell. |
+*/ |
+static float cellGrowth(Rtree *pRtree, RtreeCell *p, RtreeCell *pCell){ |
+ float area; |
+ RtreeCell cell; |
+ memcpy(&cell, p, sizeof(RtreeCell)); |
+ area = cellArea(pRtree, &cell); |
+ cellUnion(pRtree, &cell, pCell); |
+ return (cellArea(pRtree, &cell)-area); |
+} |
+ |
+#if VARIANT_RSTARTREE_CHOOSESUBTREE || VARIANT_RSTARTREE_SPLIT |
+static float cellOverlap( |
+ Rtree *pRtree, |
+ RtreeCell *p, |
+ RtreeCell *aCell, |
+ int nCell, |
+ int iExclude |
+){ |
+ int ii; |
+ float overlap = 0.0; |
+ for(ii=0; ii<nCell; ii++){ |
+#if VARIANT_RSTARTREE_CHOOSESUBTREE |
+ if( ii!=iExclude ) |
+#else |
+ assert( iExclude==-1 ); |
+ UNUSED_PARAMETER(iExclude); |
+#endif |
+ { |
+ int jj; |
+ float o = 1.0; |
+ for(jj=0; jj<(pRtree->nDim*2); jj+=2){ |
+ double x1; |
+ double x2; |
+ |
+ x1 = MAX(DCOORD(p->aCoord[jj]), DCOORD(aCell[ii].aCoord[jj])); |
+ x2 = MIN(DCOORD(p->aCoord[jj+1]), DCOORD(aCell[ii].aCoord[jj+1])); |
+ |
+ if( x2<x1 ){ |
+ o = 0.0; |
+ break; |
+ }else{ |
+ o = o * (x2-x1); |
+ } |
+ } |
+ overlap += o; |
+ } |
+ } |
+ return overlap; |
+} |
+#endif |
+ |
+#if VARIANT_RSTARTREE_CHOOSESUBTREE |
+static float cellOverlapEnlargement( |
+ Rtree *pRtree, |
+ RtreeCell *p, |
+ RtreeCell *pInsert, |
+ RtreeCell *aCell, |
+ int nCell, |
+ int iExclude |
+){ |
+ float before; |
+ float after; |
+ before = cellOverlap(pRtree, p, aCell, nCell, iExclude); |
+ cellUnion(pRtree, p, pInsert); |
+ after = cellOverlap(pRtree, p, aCell, nCell, iExclude); |
+ return after-before; |
+} |
+#endif |
+ |
+ |
+/* |
+** This function implements the ChooseLeaf algorithm from Gutman[84]. |
+** ChooseSubTree in r*tree terminology. |
+*/ |
+static int ChooseLeaf( |
+ Rtree *pRtree, /* Rtree table */ |
+ RtreeCell *pCell, /* Cell to insert into rtree */ |
+ int iHeight, /* Height of sub-tree rooted at pCell */ |
+ RtreeNode **ppLeaf /* OUT: Selected leaf page */ |
+){ |
+ int rc; |
+ int ii; |
+ RtreeNode *pNode; |
+ rc = nodeAcquire(pRtree, 1, 0, &pNode); |
+ |
+ for(ii=0; rc==SQLITE_OK && ii<(pRtree->iDepth-iHeight); ii++){ |
+ int iCell; |
+ sqlite3_int64 iBest; |
+ |
+ float fMinGrowth; |
+ float fMinArea; |
+ float fMinOverlap; |
+ |
+ int nCell = NCELL(pNode); |
+ RtreeCell cell; |
+ RtreeNode *pChild; |
+ |
+ RtreeCell *aCell = 0; |
+ |
+#if VARIANT_RSTARTREE_CHOOSESUBTREE |
+ if( ii==(pRtree->iDepth-1) ){ |
+ int jj; |
+ aCell = sqlite3_malloc(sizeof(RtreeCell)*nCell); |
+ if( !aCell ){ |
+ rc = SQLITE_NOMEM; |
+ nodeRelease(pRtree, pNode); |
+ pNode = 0; |
+ continue; |
+ } |
+ for(jj=0; jj<nCell; jj++){ |
+ nodeGetCell(pRtree, pNode, jj, &aCell[jj]); |
+ } |
+ } |
+#endif |
+ |
+ /* Select the child node which will be enlarged the least if pCell |
+ ** is inserted into it. Resolve ties by choosing the entry with |
+ ** the smallest area. |
+ */ |
+ for(iCell=0; iCell<nCell; iCell++){ |
+ int bBest = 0; |
+ float growth; |
+ float area; |
+ float overlap = 0.0; |
+ nodeGetCell(pRtree, pNode, iCell, &cell); |
+ growth = cellGrowth(pRtree, &cell, pCell); |
+ area = cellArea(pRtree, &cell); |
+ |
+#if VARIANT_RSTARTREE_CHOOSESUBTREE |
+ if( ii==(pRtree->iDepth-1) ){ |
+ overlap = cellOverlapEnlargement(pRtree,&cell,pCell,aCell,nCell,iCell); |
+ } |
+ if( (iCell==0) |
+ || (overlap<fMinOverlap) |
+ || (overlap==fMinOverlap && growth<fMinGrowth) |
+ || (overlap==fMinOverlap && growth==fMinGrowth && area<fMinArea) |
+ ){ |
+ bBest = 1; |
+ } |
+#else |
+ if( iCell==0||growth<fMinGrowth||(growth==fMinGrowth && area<fMinArea) ){ |
+ bBest = 1; |
+ } |
+#endif |
+ if( bBest ){ |
+ fMinOverlap = overlap; |
+ fMinGrowth = growth; |
+ fMinArea = area; |
+ iBest = cell.iRowid; |
+ } |
+ } |
+ |
+ sqlite3_free(aCell); |
+ rc = nodeAcquire(pRtree, iBest, pNode, &pChild); |
+ nodeRelease(pRtree, pNode); |
+ pNode = pChild; |
+ } |
+ |
+ *ppLeaf = pNode; |
+ return rc; |
+} |
+ |
+/* |
+** A cell with the same content as pCell has just been inserted into |
+** the node pNode. This function updates the bounding box cells in |
+** all ancestor elements. |
+*/ |
+static int AdjustTree( |
+ Rtree *pRtree, /* Rtree table */ |
+ RtreeNode *pNode, /* Adjust ancestry of this node. */ |
+ RtreeCell *pCell /* This cell was just inserted */ |
+){ |
+ RtreeNode *p = pNode; |
+ while( p->pParent ){ |
+ RtreeNode *pParent = p->pParent; |
+ RtreeCell cell; |
+ int iCell; |
+ |
+ if( nodeParentIndex(pRtree, p, &iCell) ){ |
+ return SQLITE_CORRUPT; |
+ } |
+ |
+ nodeGetCell(pRtree, pParent, iCell, &cell); |
+ if( !cellContains(pRtree, &cell, pCell) ){ |
+ cellUnion(pRtree, &cell, pCell); |
+ nodeOverwriteCell(pRtree, pParent, &cell, iCell); |
+ } |
+ |
+ p = pParent; |
+ } |
+ return SQLITE_OK; |
+} |
+ |
+/* |
+** Write mapping (iRowid->iNode) to the <rtree>_rowid table. |
+*/ |
+static int rowidWrite(Rtree *pRtree, sqlite3_int64 iRowid, sqlite3_int64 iNode){ |
+ sqlite3_bind_int64(pRtree->pWriteRowid, 1, iRowid); |
+ sqlite3_bind_int64(pRtree->pWriteRowid, 2, iNode); |
+ sqlite3_step(pRtree->pWriteRowid); |
+ return sqlite3_reset(pRtree->pWriteRowid); |
+} |
+ |
+/* |
+** Write mapping (iNode->iPar) to the <rtree>_parent table. |
+*/ |
+static int parentWrite(Rtree *pRtree, sqlite3_int64 iNode, sqlite3_int64 iPar){ |
+ sqlite3_bind_int64(pRtree->pWriteParent, 1, iNode); |
+ sqlite3_bind_int64(pRtree->pWriteParent, 2, iPar); |
+ sqlite3_step(pRtree->pWriteParent); |
+ return sqlite3_reset(pRtree->pWriteParent); |
+} |
+ |
+static int rtreeInsertCell(Rtree *, RtreeNode *, RtreeCell *, int); |
+ |
+#if VARIANT_GUTTMAN_LINEAR_SPLIT |
+/* |
+** Implementation of the linear variant of the PickNext() function from |
+** Guttman[84]. |
+*/ |
+static RtreeCell *LinearPickNext( |
+ Rtree *pRtree, |
+ RtreeCell *aCell, |
+ int nCell, |
+ RtreeCell *pLeftBox, |
+ RtreeCell *pRightBox, |
+ int *aiUsed |
+){ |
+ int ii; |
+ for(ii=0; aiUsed[ii]; ii++); |
+ aiUsed[ii] = 1; |
+ return &aCell[ii]; |
+} |
+ |
+/* |
+** Implementation of the linear variant of the PickSeeds() function from |
+** Guttman[84]. |
+*/ |
+static void LinearPickSeeds( |
+ Rtree *pRtree, |
+ RtreeCell *aCell, |
+ int nCell, |
+ int *piLeftSeed, |
+ int *piRightSeed |
+){ |
+ int i; |
+ int iLeftSeed = 0; |
+ int iRightSeed = 1; |
+ float maxNormalInnerWidth = 0.0; |
+ |
+ /* Pick two "seed" cells from the array of cells. The algorithm used |
+ ** here is the LinearPickSeeds algorithm from Gutman[1984]. The |
+ ** indices of the two seed cells in the array are stored in local |
+ ** variables iLeftSeek and iRightSeed. |
+ */ |
+ for(i=0; i<pRtree->nDim; i++){ |
+ float x1 = DCOORD(aCell[0].aCoord[i*2]); |
+ float x2 = DCOORD(aCell[0].aCoord[i*2+1]); |
+ float x3 = x1; |
+ float x4 = x2; |
+ int jj; |
+ |
+ int iCellLeft = 0; |
+ int iCellRight = 0; |
+ |
+ for(jj=1; jj<nCell; jj++){ |
+ float left = DCOORD(aCell[jj].aCoord[i*2]); |
+ float right = DCOORD(aCell[jj].aCoord[i*2+1]); |
+ |
+ if( left<x1 ) x1 = left; |
+ if( right>x4 ) x4 = right; |
+ if( left>x3 ){ |
+ x3 = left; |
+ iCellRight = jj; |
+ } |
+ if( right<x2 ){ |
+ x2 = right; |
+ iCellLeft = jj; |
+ } |
+ } |
+ |
+ if( x4!=x1 ){ |
+ float normalwidth = (x3 - x2) / (x4 - x1); |
+ if( normalwidth>maxNormalInnerWidth ){ |
+ iLeftSeed = iCellLeft; |
+ iRightSeed = iCellRight; |
+ } |
+ } |
+ } |
+ |
+ *piLeftSeed = iLeftSeed; |
+ *piRightSeed = iRightSeed; |
+} |
+#endif /* VARIANT_GUTTMAN_LINEAR_SPLIT */ |
+ |
+#if VARIANT_GUTTMAN_QUADRATIC_SPLIT |
+/* |
+** Implementation of the quadratic variant of the PickNext() function from |
+** Guttman[84]. |
+*/ |
+static RtreeCell *QuadraticPickNext( |
+ Rtree *pRtree, |
+ RtreeCell *aCell, |
+ int nCell, |
+ RtreeCell *pLeftBox, |
+ RtreeCell *pRightBox, |
+ int *aiUsed |
+){ |
+ #define FABS(a) ((a)<0.0?-1.0*(a):(a)) |
+ |
+ int iSelect = -1; |
+ float fDiff; |
+ int ii; |
+ for(ii=0; ii<nCell; ii++){ |
+ if( aiUsed[ii]==0 ){ |
+ float left = cellGrowth(pRtree, pLeftBox, &aCell[ii]); |
+ float right = cellGrowth(pRtree, pLeftBox, &aCell[ii]); |
+ float diff = FABS(right-left); |
+ if( iSelect<0 || diff>fDiff ){ |
+ fDiff = diff; |
+ iSelect = ii; |
+ } |
+ } |
+ } |
+ aiUsed[iSelect] = 1; |
+ return &aCell[iSelect]; |
+} |
+ |
+/* |
+** Implementation of the quadratic variant of the PickSeeds() function from |
+** Guttman[84]. |
+*/ |
+static void QuadraticPickSeeds( |
+ Rtree *pRtree, |
+ RtreeCell *aCell, |
+ int nCell, |
+ int *piLeftSeed, |
+ int *piRightSeed |
+){ |
+ int ii; |
+ int jj; |
+ |
+ int iLeftSeed = 0; |
+ int iRightSeed = 1; |
+ float fWaste = 0.0; |
+ |
+ for(ii=0; ii<nCell; ii++){ |
+ for(jj=ii+1; jj<nCell; jj++){ |
+ float right = cellArea(pRtree, &aCell[jj]); |
+ float growth = cellGrowth(pRtree, &aCell[ii], &aCell[jj]); |
+ float waste = growth - right; |
+ |
+ if( waste>fWaste ){ |
+ iLeftSeed = ii; |
+ iRightSeed = jj; |
+ fWaste = waste; |
+ } |
+ } |
+ } |
+ |
+ *piLeftSeed = iLeftSeed; |
+ *piRightSeed = iRightSeed; |
+} |
+#endif /* VARIANT_GUTTMAN_QUADRATIC_SPLIT */ |
+ |
+/* |
+** Arguments aIdx, aDistance and aSpare all point to arrays of size |
+** nIdx. The aIdx array contains the set of integers from 0 to |
+** (nIdx-1) in no particular order. This function sorts the values |
+** in aIdx according to the indexed values in aDistance. For |
+** example, assuming the inputs: |
+** |
+** aIdx = { 0, 1, 2, 3 } |
+** aDistance = { 5.0, 2.0, 7.0, 6.0 } |
+** |
+** this function sets the aIdx array to contain: |
+** |
+** aIdx = { 0, 1, 2, 3 } |
+** |
+** The aSpare array is used as temporary working space by the |
+** sorting algorithm. |
+*/ |
+static void SortByDistance( |
+ int *aIdx, |
+ int nIdx, |
+ float *aDistance, |
+ int *aSpare |
+){ |
+ if( nIdx>1 ){ |
+ int iLeft = 0; |
+ int iRight = 0; |
+ |
+ int nLeft = nIdx/2; |
+ int nRight = nIdx-nLeft; |
+ int *aLeft = aIdx; |
+ int *aRight = &aIdx[nLeft]; |
+ |
+ SortByDistance(aLeft, nLeft, aDistance, aSpare); |
+ SortByDistance(aRight, nRight, aDistance, aSpare); |
+ |
+ memcpy(aSpare, aLeft, sizeof(int)*nLeft); |
+ aLeft = aSpare; |
+ |
+ while( iLeft<nLeft || iRight<nRight ){ |
+ if( iLeft==nLeft ){ |
+ aIdx[iLeft+iRight] = aRight[iRight]; |
+ iRight++; |
+ }else if( iRight==nRight ){ |
+ aIdx[iLeft+iRight] = aLeft[iLeft]; |
+ iLeft++; |
+ }else{ |
+ float fLeft = aDistance[aLeft[iLeft]]; |
+ float fRight = aDistance[aRight[iRight]]; |
+ if( fLeft<fRight ){ |
+ aIdx[iLeft+iRight] = aLeft[iLeft]; |
+ iLeft++; |
+ }else{ |
+ aIdx[iLeft+iRight] = aRight[iRight]; |
+ iRight++; |
+ } |
+ } |
+ } |
+ |
+#if 0 |
+ /* Check that the sort worked */ |
+ { |
+ int jj; |
+ for(jj=1; jj<nIdx; jj++){ |
+ float left = aDistance[aIdx[jj-1]]; |
+ float right = aDistance[aIdx[jj]]; |
+ assert( left<=right ); |
+ } |
+ } |
+#endif |
+ } |
+} |
+ |
+/* |
+** Arguments aIdx, aCell and aSpare all point to arrays of size |
+** nIdx. The aIdx array contains the set of integers from 0 to |
+** (nIdx-1) in no particular order. This function sorts the values |
+** in aIdx according to dimension iDim of the cells in aCell. The |
+** minimum value of dimension iDim is considered first, the |
+** maximum used to break ties. |
+** |
+** The aSpare array is used as temporary working space by the |
+** sorting algorithm. |
+*/ |
+static void SortByDimension( |
+ Rtree *pRtree, |
+ int *aIdx, |
+ int nIdx, |
+ int iDim, |
+ RtreeCell *aCell, |
+ int *aSpare |
+){ |
+ if( nIdx>1 ){ |
+ |
+ int iLeft = 0; |
+ int iRight = 0; |
+ |
+ int nLeft = nIdx/2; |
+ int nRight = nIdx-nLeft; |
+ int *aLeft = aIdx; |
+ int *aRight = &aIdx[nLeft]; |
+ |
+ SortByDimension(pRtree, aLeft, nLeft, iDim, aCell, aSpare); |
+ SortByDimension(pRtree, aRight, nRight, iDim, aCell, aSpare); |
+ |
+ memcpy(aSpare, aLeft, sizeof(int)*nLeft); |
+ aLeft = aSpare; |
+ while( iLeft<nLeft || iRight<nRight ){ |
+ double xleft1 = DCOORD(aCell[aLeft[iLeft]].aCoord[iDim*2]); |
+ double xleft2 = DCOORD(aCell[aLeft[iLeft]].aCoord[iDim*2+1]); |
+ double xright1 = DCOORD(aCell[aRight[iRight]].aCoord[iDim*2]); |
+ double xright2 = DCOORD(aCell[aRight[iRight]].aCoord[iDim*2+1]); |
+ if( (iLeft!=nLeft) && ((iRight==nRight) |
+ || (xleft1<xright1) |
+ || (xleft1==xright1 && xleft2<xright2) |
+ )){ |
+ aIdx[iLeft+iRight] = aLeft[iLeft]; |
+ iLeft++; |
+ }else{ |
+ aIdx[iLeft+iRight] = aRight[iRight]; |
+ iRight++; |
+ } |
+ } |
+ |
+#if 0 |
+ /* Check that the sort worked */ |
+ { |
+ int jj; |
+ for(jj=1; jj<nIdx; jj++){ |
+ float xleft1 = aCell[aIdx[jj-1]].aCoord[iDim*2]; |
+ float xleft2 = aCell[aIdx[jj-1]].aCoord[iDim*2+1]; |
+ float xright1 = aCell[aIdx[jj]].aCoord[iDim*2]; |
+ float xright2 = aCell[aIdx[jj]].aCoord[iDim*2+1]; |
+ assert( xleft1<=xright1 && (xleft1<xright1 || xleft2<=xright2) ); |
+ } |
+ } |
+#endif |
+ } |
+} |
+ |
+#if VARIANT_RSTARTREE_SPLIT |
+/* |
+** Implementation of the R*-tree variant of SplitNode from Beckman[1990]. |
+*/ |
+static int splitNodeStartree( |
+ Rtree *pRtree, |
+ RtreeCell *aCell, |
+ int nCell, |
+ RtreeNode *pLeft, |
+ RtreeNode *pRight, |
+ RtreeCell *pBboxLeft, |
+ RtreeCell *pBboxRight |
+){ |
+ int **aaSorted; |
+ int *aSpare; |
+ int ii; |
+ |
+ int iBestDim; |
+ int iBestSplit; |
+ float fBestMargin; |
+ |
+ int nByte = (pRtree->nDim+1)*(sizeof(int*)+nCell*sizeof(int)); |
+ |
+ aaSorted = (int **)sqlite3_malloc(nByte); |
+ if( !aaSorted ){ |
+ return SQLITE_NOMEM; |
+ } |
+ |
+ aSpare = &((int *)&aaSorted[pRtree->nDim])[pRtree->nDim*nCell]; |
+ memset(aaSorted, 0, nByte); |
+ for(ii=0; ii<pRtree->nDim; ii++){ |
+ int jj; |
+ aaSorted[ii] = &((int *)&aaSorted[pRtree->nDim])[ii*nCell]; |
+ for(jj=0; jj<nCell; jj++){ |
+ aaSorted[ii][jj] = jj; |
+ } |
+ SortByDimension(pRtree, aaSorted[ii], nCell, ii, aCell, aSpare); |
+ } |
+ |
+ for(ii=0; ii<pRtree->nDim; ii++){ |
+ float margin = 0.0; |
+ float fBestOverlap; |
+ float fBestArea; |
+ int iBestLeft; |
+ int nLeft; |
+ |
+ for( |
+ nLeft=RTREE_MINCELLS(pRtree); |
+ nLeft<=(nCell-RTREE_MINCELLS(pRtree)); |
+ nLeft++ |
+ ){ |
+ RtreeCell left; |
+ RtreeCell right; |
+ int kk; |
+ float overlap; |
+ float area; |
+ |
+ memcpy(&left, &aCell[aaSorted[ii][0]], sizeof(RtreeCell)); |
+ memcpy(&right, &aCell[aaSorted[ii][nCell-1]], sizeof(RtreeCell)); |
+ for(kk=1; kk<(nCell-1); kk++){ |
+ if( kk<nLeft ){ |
+ cellUnion(pRtree, &left, &aCell[aaSorted[ii][kk]]); |
+ }else{ |
+ cellUnion(pRtree, &right, &aCell[aaSorted[ii][kk]]); |
+ } |
+ } |
+ margin += cellMargin(pRtree, &left); |
+ margin += cellMargin(pRtree, &right); |
+ overlap = cellOverlap(pRtree, &left, &right, 1, -1); |
+ area = cellArea(pRtree, &left) + cellArea(pRtree, &right); |
+ if( (nLeft==RTREE_MINCELLS(pRtree)) |
+ || (overlap<fBestOverlap) |
+ || (overlap==fBestOverlap && area<fBestArea) |
+ ){ |
+ iBestLeft = nLeft; |
+ fBestOverlap = overlap; |
+ fBestArea = area; |
+ } |
+ } |
+ |
+ if( ii==0 || margin<fBestMargin ){ |
+ iBestDim = ii; |
+ fBestMargin = margin; |
+ iBestSplit = iBestLeft; |
+ } |
+ } |
+ |
+ memcpy(pBboxLeft, &aCell[aaSorted[iBestDim][0]], sizeof(RtreeCell)); |
+ memcpy(pBboxRight, &aCell[aaSorted[iBestDim][iBestSplit]], sizeof(RtreeCell)); |
+ for(ii=0; ii<nCell; ii++){ |
+ RtreeNode *pTarget = (ii<iBestSplit)?pLeft:pRight; |
+ RtreeCell *pBbox = (ii<iBestSplit)?pBboxLeft:pBboxRight; |
+ RtreeCell *pCell = &aCell[aaSorted[iBestDim][ii]]; |
+ nodeInsertCell(pRtree, pTarget, pCell); |
+ cellUnion(pRtree, pBbox, pCell); |
+ } |
+ |
+ sqlite3_free(aaSorted); |
+ return SQLITE_OK; |
+} |
+#endif |
+ |
+#if VARIANT_GUTTMAN_SPLIT |
+/* |
+** Implementation of the regular R-tree SplitNode from Guttman[1984]. |
+*/ |
+static int splitNodeGuttman( |
+ Rtree *pRtree, |
+ RtreeCell *aCell, |
+ int nCell, |
+ RtreeNode *pLeft, |
+ RtreeNode *pRight, |
+ RtreeCell *pBboxLeft, |
+ RtreeCell *pBboxRight |
+){ |
+ int iLeftSeed = 0; |
+ int iRightSeed = 1; |
+ int *aiUsed; |
+ int i; |
+ |
+ aiUsed = sqlite3_malloc(sizeof(int)*nCell); |
+ if( !aiUsed ){ |
+ return SQLITE_NOMEM; |
+ } |
+ memset(aiUsed, 0, sizeof(int)*nCell); |
+ |
+ PickSeeds(pRtree, aCell, nCell, &iLeftSeed, &iRightSeed); |
+ |
+ memcpy(pBboxLeft, &aCell[iLeftSeed], sizeof(RtreeCell)); |
+ memcpy(pBboxRight, &aCell[iRightSeed], sizeof(RtreeCell)); |
+ nodeInsertCell(pRtree, pLeft, &aCell[iLeftSeed]); |
+ nodeInsertCell(pRtree, pRight, &aCell[iRightSeed]); |
+ aiUsed[iLeftSeed] = 1; |
+ aiUsed[iRightSeed] = 1; |
+ |
+ for(i=nCell-2; i>0; i--){ |
+ RtreeCell *pNext; |
+ pNext = PickNext(pRtree, aCell, nCell, pBboxLeft, pBboxRight, aiUsed); |
+ float diff = |
+ cellGrowth(pRtree, pBboxLeft, pNext) - |
+ cellGrowth(pRtree, pBboxRight, pNext) |
+ ; |
+ if( (RTREE_MINCELLS(pRtree)-NCELL(pRight)==i) |
+ || (diff>0.0 && (RTREE_MINCELLS(pRtree)-NCELL(pLeft)!=i)) |
+ ){ |
+ nodeInsertCell(pRtree, pRight, pNext); |
+ cellUnion(pRtree, pBboxRight, pNext); |
+ }else{ |
+ nodeInsertCell(pRtree, pLeft, pNext); |
+ cellUnion(pRtree, pBboxLeft, pNext); |
+ } |
+ } |
+ |
+ sqlite3_free(aiUsed); |
+ return SQLITE_OK; |
+} |
+#endif |
+ |
+static int updateMapping( |
+ Rtree *pRtree, |
+ i64 iRowid, |
+ RtreeNode *pNode, |
+ int iHeight |
+){ |
+ int (*xSetMapping)(Rtree *, sqlite3_int64, sqlite3_int64); |
+ xSetMapping = ((iHeight==0)?rowidWrite:parentWrite); |
+ if( iHeight>0 ){ |
+ RtreeNode *pChild = nodeHashLookup(pRtree, iRowid); |
+ if( pChild ){ |
+ nodeRelease(pRtree, pChild->pParent); |
+ nodeReference(pNode); |
+ pChild->pParent = pNode; |
+ } |
+ } |
+ return xSetMapping(pRtree, iRowid, pNode->iNode); |
+} |
+ |
+static int SplitNode( |
+ Rtree *pRtree, |
+ RtreeNode *pNode, |
+ RtreeCell *pCell, |
+ int iHeight |
+){ |
+ int i; |
+ int newCellIsRight = 0; |
+ |
+ int rc = SQLITE_OK; |
+ int nCell = NCELL(pNode); |
+ RtreeCell *aCell; |
+ int *aiUsed; |
+ |
+ RtreeNode *pLeft = 0; |
+ RtreeNode *pRight = 0; |
+ |
+ RtreeCell leftbbox; |
+ RtreeCell rightbbox; |
+ |
+ /* Allocate an array and populate it with a copy of pCell and |
+ ** all cells from node pLeft. Then zero the original node. |
+ */ |
+ aCell = sqlite3_malloc((sizeof(RtreeCell)+sizeof(int))*(nCell+1)); |
+ if( !aCell ){ |
+ rc = SQLITE_NOMEM; |
+ goto splitnode_out; |
+ } |
+ aiUsed = (int *)&aCell[nCell+1]; |
+ memset(aiUsed, 0, sizeof(int)*(nCell+1)); |
+ for(i=0; i<nCell; i++){ |
+ nodeGetCell(pRtree, pNode, i, &aCell[i]); |
+ } |
+ nodeZero(pRtree, pNode); |
+ memcpy(&aCell[nCell], pCell, sizeof(RtreeCell)); |
+ nCell++; |
+ |
+ if( pNode->iNode==1 ){ |
+ pRight = nodeNew(pRtree, pNode); |
+ pLeft = nodeNew(pRtree, pNode); |
+ pRtree->iDepth++; |
+ pNode->isDirty = 1; |
+ writeInt16(pNode->zData, pRtree->iDepth); |
+ }else{ |
+ pLeft = pNode; |
+ pRight = nodeNew(pRtree, pLeft->pParent); |
+ nodeReference(pLeft); |
+ } |
+ |
+ if( !pLeft || !pRight ){ |
+ rc = SQLITE_NOMEM; |
+ goto splitnode_out; |
+ } |
+ |
+ memset(pLeft->zData, 0, pRtree->iNodeSize); |
+ memset(pRight->zData, 0, pRtree->iNodeSize); |
+ |
+ rc = AssignCells(pRtree, aCell, nCell, pLeft, pRight, &leftbbox, &rightbbox); |
+ if( rc!=SQLITE_OK ){ |
+ goto splitnode_out; |
+ } |
+ |
+ /* Ensure both child nodes have node numbers assigned to them by calling |
+ ** nodeWrite(). Node pRight always needs a node number, as it was created |
+ ** by nodeNew() above. But node pLeft sometimes already has a node number. |
+ ** In this case avoid the all to nodeWrite(). |
+ */ |
+ if( SQLITE_OK!=(rc = nodeWrite(pRtree, pRight)) |
+ || (0==pLeft->iNode && SQLITE_OK!=(rc = nodeWrite(pRtree, pLeft))) |
+ ){ |
+ goto splitnode_out; |
+ } |
+ |
+ rightbbox.iRowid = pRight->iNode; |
+ leftbbox.iRowid = pLeft->iNode; |
+ |
+ if( pNode->iNode==1 ){ |
+ rc = rtreeInsertCell(pRtree, pLeft->pParent, &leftbbox, iHeight+1); |
+ if( rc!=SQLITE_OK ){ |
+ goto splitnode_out; |
+ } |
+ }else{ |
+ RtreeNode *pParent = pLeft->pParent; |
+ int iCell; |
+ rc = nodeParentIndex(pRtree, pLeft, &iCell); |
+ if( rc==SQLITE_OK ){ |
+ nodeOverwriteCell(pRtree, pParent, &leftbbox, iCell); |
+ rc = AdjustTree(pRtree, pParent, &leftbbox); |
+ } |
+ if( rc!=SQLITE_OK ){ |
+ goto splitnode_out; |
+ } |
+ } |
+ if( (rc = rtreeInsertCell(pRtree, pRight->pParent, &rightbbox, iHeight+1)) ){ |
+ goto splitnode_out; |
+ } |
+ |
+ for(i=0; i<NCELL(pRight); i++){ |
+ i64 iRowid = nodeGetRowid(pRtree, pRight, i); |
+ rc = updateMapping(pRtree, iRowid, pRight, iHeight); |
+ if( iRowid==pCell->iRowid ){ |
+ newCellIsRight = 1; |
+ } |
+ if( rc!=SQLITE_OK ){ |
+ goto splitnode_out; |
+ } |
+ } |
+ if( pNode->iNode==1 ){ |
+ for(i=0; i<NCELL(pLeft); i++){ |
+ i64 iRowid = nodeGetRowid(pRtree, pLeft, i); |
+ rc = updateMapping(pRtree, iRowid, pLeft, iHeight); |
+ if( rc!=SQLITE_OK ){ |
+ goto splitnode_out; |
+ } |
+ } |
+ }else if( newCellIsRight==0 ){ |
+ rc = updateMapping(pRtree, pCell->iRowid, pLeft, iHeight); |
+ } |
+ |
+ if( rc==SQLITE_OK ){ |
+ rc = nodeRelease(pRtree, pRight); |
+ pRight = 0; |
+ } |
+ if( rc==SQLITE_OK ){ |
+ rc = nodeRelease(pRtree, pLeft); |
+ pLeft = 0; |
+ } |
+ |
+splitnode_out: |
+ nodeRelease(pRtree, pRight); |
+ nodeRelease(pRtree, pLeft); |
+ sqlite3_free(aCell); |
+ return rc; |
+} |
+ |
+/* |
+** If node pLeaf is not the root of the r-tree and its pParent pointer is |
+** still NULL, load all ancestor nodes of pLeaf into memory and populate |
+** the pLeaf->pParent chain all the way up to the root node. |
+** |
+** This operation is required when a row is deleted (or updated - an update |
+** is implemented as a delete followed by an insert). SQLite provides the |
+** rowid of the row to delete, which can be used to find the leaf on which |
+** the entry resides (argument pLeaf). Once the leaf is located, this |
+** function is called to determine its ancestry. |
+*/ |
+static int fixLeafParent(Rtree *pRtree, RtreeNode *pLeaf){ |
+ int rc = SQLITE_OK; |
+ RtreeNode *pChild = pLeaf; |
+ while( rc==SQLITE_OK && pChild->iNode!=1 && pChild->pParent==0 ){ |
+ int rc2 = SQLITE_OK; /* sqlite3_reset() return code */ |
+ sqlite3_bind_int64(pRtree->pReadParent, 1, pChild->iNode); |
+ rc = sqlite3_step(pRtree->pReadParent); |
+ if( rc==SQLITE_ROW ){ |
+ RtreeNode *pTest; /* Used to test for reference loops */ |
+ i64 iNode; /* Node number of parent node */ |
+ |
+ /* Before setting pChild->pParent, test that we are not creating a |
+ ** loop of references (as we would if, say, pChild==pParent). We don't |
+ ** want to do this as it leads to a memory leak when trying to delete |
+ ** the referenced counted node structures. |
+ */ |
+ iNode = sqlite3_column_int64(pRtree->pReadParent, 0); |
+ for(pTest=pLeaf; pTest && pTest->iNode!=iNode; pTest=pTest->pParent); |
+ if( !pTest ){ |
+ rc2 = nodeAcquire(pRtree, iNode, 0, &pChild->pParent); |
+ } |
+ } |
+ rc = sqlite3_reset(pRtree->pReadParent); |
+ if( rc==SQLITE_OK ) rc = rc2; |
+ if( rc==SQLITE_OK && !pChild->pParent ) rc = SQLITE_CORRUPT; |
+ pChild = pChild->pParent; |
+ } |
+ return rc; |
+} |
+ |
+static int deleteCell(Rtree *, RtreeNode *, int, int); |
+ |
+static int removeNode(Rtree *pRtree, RtreeNode *pNode, int iHeight){ |
+ int rc; |
+ int rc2; |
+ RtreeNode *pParent; |
+ int iCell; |
+ |
+ assert( pNode->nRef==1 ); |
+ |
+ /* Remove the entry in the parent cell. */ |
+ rc = nodeParentIndex(pRtree, pNode, &iCell); |
+ if( rc==SQLITE_OK ){ |
+ pParent = pNode->pParent; |
+ pNode->pParent = 0; |
+ rc = deleteCell(pRtree, pParent, iCell, iHeight+1); |
+ } |
+ rc2 = nodeRelease(pRtree, pParent); |
+ if( rc==SQLITE_OK ){ |
+ rc = rc2; |
+ } |
+ if( rc!=SQLITE_OK ){ |
+ return rc; |
+ } |
+ |
+ /* Remove the xxx_node entry. */ |
+ sqlite3_bind_int64(pRtree->pDeleteNode, 1, pNode->iNode); |
+ sqlite3_step(pRtree->pDeleteNode); |
+ if( SQLITE_OK!=(rc = sqlite3_reset(pRtree->pDeleteNode)) ){ |
+ return rc; |
+ } |
+ |
+ /* Remove the xxx_parent entry. */ |
+ sqlite3_bind_int64(pRtree->pDeleteParent, 1, pNode->iNode); |
+ sqlite3_step(pRtree->pDeleteParent); |
+ if( SQLITE_OK!=(rc = sqlite3_reset(pRtree->pDeleteParent)) ){ |
+ return rc; |
+ } |
+ |
+ /* Remove the node from the in-memory hash table and link it into |
+ ** the Rtree.pDeleted list. Its contents will be re-inserted later on. |
+ */ |
+ nodeHashDelete(pRtree, pNode); |
+ pNode->iNode = iHeight; |
+ pNode->pNext = pRtree->pDeleted; |
+ pNode->nRef++; |
+ pRtree->pDeleted = pNode; |
+ |
+ return SQLITE_OK; |
+} |
+ |
+static int fixBoundingBox(Rtree *pRtree, RtreeNode *pNode){ |
+ RtreeNode *pParent = pNode->pParent; |
+ int rc = SQLITE_OK; |
+ if( pParent ){ |
+ int ii; |
+ int nCell = NCELL(pNode); |
+ RtreeCell box; /* Bounding box for pNode */ |
+ nodeGetCell(pRtree, pNode, 0, &box); |
+ for(ii=1; ii<nCell; ii++){ |
+ RtreeCell cell; |
+ nodeGetCell(pRtree, pNode, ii, &cell); |
+ cellUnion(pRtree, &box, &cell); |
+ } |
+ box.iRowid = pNode->iNode; |
+ rc = nodeParentIndex(pRtree, pNode, &ii); |
+ if( rc==SQLITE_OK ){ |
+ nodeOverwriteCell(pRtree, pParent, &box, ii); |
+ rc = fixBoundingBox(pRtree, pParent); |
+ } |
+ } |
+ return rc; |
+} |
+ |
+/* |
+** Delete the cell at index iCell of node pNode. After removing the |
+** cell, adjust the r-tree data structure if required. |
+*/ |
+static int deleteCell(Rtree *pRtree, RtreeNode *pNode, int iCell, int iHeight){ |
+ RtreeNode *pParent; |
+ int rc; |
+ |
+ if( SQLITE_OK!=(rc = fixLeafParent(pRtree, pNode)) ){ |
+ return rc; |
+ } |
+ |
+ /* Remove the cell from the node. This call just moves bytes around |
+ ** the in-memory node image, so it cannot fail. |
+ */ |
+ nodeDeleteCell(pRtree, pNode, iCell); |
+ |
+ /* If the node is not the tree root and now has less than the minimum |
+ ** number of cells, remove it from the tree. Otherwise, update the |
+ ** cell in the parent node so that it tightly contains the updated |
+ ** node. |
+ */ |
+ pParent = pNode->pParent; |
+ assert( pParent || pNode->iNode==1 ); |
+ if( pParent ){ |
+ if( NCELL(pNode)<RTREE_MINCELLS(pRtree) ){ |
+ rc = removeNode(pRtree, pNode, iHeight); |
+ }else{ |
+ rc = fixBoundingBox(pRtree, pNode); |
+ } |
+ } |
+ |
+ return rc; |
+} |
+ |
+static int Reinsert( |
+ Rtree *pRtree, |
+ RtreeNode *pNode, |
+ RtreeCell *pCell, |
+ int iHeight |
+){ |
+ int *aOrder; |
+ int *aSpare; |
+ RtreeCell *aCell; |
+ float *aDistance; |
+ int nCell; |
+ float aCenterCoord[RTREE_MAX_DIMENSIONS]; |
+ int iDim; |
+ int ii; |
+ int rc = SQLITE_OK; |
+ |
+ memset(aCenterCoord, 0, sizeof(float)*RTREE_MAX_DIMENSIONS); |
+ |
+ nCell = NCELL(pNode)+1; |
+ |
+ /* Allocate the buffers used by this operation. The allocation is |
+ ** relinquished before this function returns. |
+ */ |
+ aCell = (RtreeCell *)sqlite3_malloc(nCell * ( |
+ sizeof(RtreeCell) + /* aCell array */ |
+ sizeof(int) + /* aOrder array */ |
+ sizeof(int) + /* aSpare array */ |
+ sizeof(float) /* aDistance array */ |
+ )); |
+ if( !aCell ){ |
+ return SQLITE_NOMEM; |
+ } |
+ aOrder = (int *)&aCell[nCell]; |
+ aSpare = (int *)&aOrder[nCell]; |
+ aDistance = (float *)&aSpare[nCell]; |
+ |
+ for(ii=0; ii<nCell; ii++){ |
+ if( ii==(nCell-1) ){ |
+ memcpy(&aCell[ii], pCell, sizeof(RtreeCell)); |
+ }else{ |
+ nodeGetCell(pRtree, pNode, ii, &aCell[ii]); |
+ } |
+ aOrder[ii] = ii; |
+ for(iDim=0; iDim<pRtree->nDim; iDim++){ |
+ aCenterCoord[iDim] += DCOORD(aCell[ii].aCoord[iDim*2]); |
+ aCenterCoord[iDim] += DCOORD(aCell[ii].aCoord[iDim*2+1]); |
+ } |
+ } |
+ for(iDim=0; iDim<pRtree->nDim; iDim++){ |
+ aCenterCoord[iDim] = aCenterCoord[iDim]/((float)nCell*2.0); |
+ } |
+ |
+ for(ii=0; ii<nCell; ii++){ |
+ aDistance[ii] = 0.0; |
+ for(iDim=0; iDim<pRtree->nDim; iDim++){ |
+ float coord = DCOORD(aCell[ii].aCoord[iDim*2+1]) - |
+ DCOORD(aCell[ii].aCoord[iDim*2]); |
+ aDistance[ii] += (coord-aCenterCoord[iDim])*(coord-aCenterCoord[iDim]); |
+ } |
+ } |
+ |
+ SortByDistance(aOrder, nCell, aDistance, aSpare); |
+ nodeZero(pRtree, pNode); |
+ |
+ for(ii=0; rc==SQLITE_OK && ii<(nCell-(RTREE_MINCELLS(pRtree)+1)); ii++){ |
+ RtreeCell *p = &aCell[aOrder[ii]]; |
+ nodeInsertCell(pRtree, pNode, p); |
+ if( p->iRowid==pCell->iRowid ){ |
+ if( iHeight==0 ){ |
+ rc = rowidWrite(pRtree, p->iRowid, pNode->iNode); |
+ }else{ |
+ rc = parentWrite(pRtree, p->iRowid, pNode->iNode); |
+ } |
+ } |
+ } |
+ if( rc==SQLITE_OK ){ |
+ rc = fixBoundingBox(pRtree, pNode); |
+ } |
+ for(; rc==SQLITE_OK && ii<nCell; ii++){ |
+ /* Find a node to store this cell in. pNode->iNode currently contains |
+ ** the height of the sub-tree headed by the cell. |
+ */ |
+ RtreeNode *pInsert; |
+ RtreeCell *p = &aCell[aOrder[ii]]; |
+ rc = ChooseLeaf(pRtree, p, iHeight, &pInsert); |
+ if( rc==SQLITE_OK ){ |
+ int rc2; |
+ rc = rtreeInsertCell(pRtree, pInsert, p, iHeight); |
+ rc2 = nodeRelease(pRtree, pInsert); |
+ if( rc==SQLITE_OK ){ |
+ rc = rc2; |
+ } |
+ } |
+ } |
+ |
+ sqlite3_free(aCell); |
+ return rc; |
+} |
+ |
+/* |
+** Insert cell pCell into node pNode. Node pNode is the head of a |
+** subtree iHeight high (leaf nodes have iHeight==0). |
+*/ |
+static int rtreeInsertCell( |
+ Rtree *pRtree, |
+ RtreeNode *pNode, |
+ RtreeCell *pCell, |
+ int iHeight |
+){ |
+ int rc = SQLITE_OK; |
+ if( iHeight>0 ){ |
+ RtreeNode *pChild = nodeHashLookup(pRtree, pCell->iRowid); |
+ if( pChild ){ |
+ nodeRelease(pRtree, pChild->pParent); |
+ nodeReference(pNode); |
+ pChild->pParent = pNode; |
+ } |
+ } |
+ if( nodeInsertCell(pRtree, pNode, pCell) ){ |
+#if VARIANT_RSTARTREE_REINSERT |
+ if( iHeight<=pRtree->iReinsertHeight || pNode->iNode==1){ |
+ rc = SplitNode(pRtree, pNode, pCell, iHeight); |
+ }else{ |
+ pRtree->iReinsertHeight = iHeight; |
+ rc = Reinsert(pRtree, pNode, pCell, iHeight); |
+ } |
+#else |
+ rc = SplitNode(pRtree, pNode, pCell, iHeight); |
+#endif |
+ }else{ |
+ rc = AdjustTree(pRtree, pNode, pCell); |
+ if( rc==SQLITE_OK ){ |
+ if( iHeight==0 ){ |
+ rc = rowidWrite(pRtree, pCell->iRowid, pNode->iNode); |
+ }else{ |
+ rc = parentWrite(pRtree, pCell->iRowid, pNode->iNode); |
+ } |
+ } |
+ } |
+ return rc; |
+} |
+ |
+static int reinsertNodeContent(Rtree *pRtree, RtreeNode *pNode){ |
+ int ii; |
+ int rc = SQLITE_OK; |
+ int nCell = NCELL(pNode); |
+ |
+ for(ii=0; rc==SQLITE_OK && ii<nCell; ii++){ |
+ RtreeNode *pInsert; |
+ RtreeCell cell; |
+ nodeGetCell(pRtree, pNode, ii, &cell); |
+ |
+ /* Find a node to store this cell in. pNode->iNode currently contains |
+ ** the height of the sub-tree headed by the cell. |
+ */ |
+ rc = ChooseLeaf(pRtree, &cell, pNode->iNode, &pInsert); |
+ if( rc==SQLITE_OK ){ |
+ int rc2; |
+ rc = rtreeInsertCell(pRtree, pInsert, &cell, pNode->iNode); |
+ rc2 = nodeRelease(pRtree, pInsert); |
+ if( rc==SQLITE_OK ){ |
+ rc = rc2; |
+ } |
+ } |
+ } |
+ return rc; |
+} |
+ |
+/* |
+** Select a currently unused rowid for a new r-tree record. |
+*/ |
+static int newRowid(Rtree *pRtree, i64 *piRowid){ |
+ int rc; |
+ sqlite3_bind_null(pRtree->pWriteRowid, 1); |
+ sqlite3_bind_null(pRtree->pWriteRowid, 2); |
+ sqlite3_step(pRtree->pWriteRowid); |
+ rc = sqlite3_reset(pRtree->pWriteRowid); |
+ *piRowid = sqlite3_last_insert_rowid(pRtree->db); |
+ return rc; |
+} |
+ |
+/* |
+** The xUpdate method for rtree module virtual tables. |
+*/ |
+static int rtreeUpdate( |
+ sqlite3_vtab *pVtab, |
+ int nData, |
+ sqlite3_value **azData, |
+ sqlite_int64 *pRowid |
+){ |
+ Rtree *pRtree = (Rtree *)pVtab; |
+ int rc = SQLITE_OK; |
+ |
+ rtreeReference(pRtree); |
+ |
+ assert(nData>=1); |
+ |
+ /* If azData[0] is not an SQL NULL value, it is the rowid of a |
+ ** record to delete from the r-tree table. The following block does |
+ ** just that. |
+ */ |
+ if( sqlite3_value_type(azData[0])!=SQLITE_NULL ){ |
+ i64 iDelete; /* The rowid to delete */ |
+ RtreeNode *pLeaf; /* Leaf node containing record iDelete */ |
+ int iCell; /* Index of iDelete cell in pLeaf */ |
+ RtreeNode *pRoot; |
+ |
+ /* Obtain a reference to the root node to initialise Rtree.iDepth */ |
+ rc = nodeAcquire(pRtree, 1, 0, &pRoot); |
+ |
+ /* Obtain a reference to the leaf node that contains the entry |
+ ** about to be deleted. |
+ */ |
+ if( rc==SQLITE_OK ){ |
+ iDelete = sqlite3_value_int64(azData[0]); |
+ rc = findLeafNode(pRtree, iDelete, &pLeaf); |
+ } |
+ |
+ /* Delete the cell in question from the leaf node. */ |
+ if( rc==SQLITE_OK ){ |
+ int rc2; |
+ rc = nodeRowidIndex(pRtree, pLeaf, iDelete, &iCell); |
+ if( rc==SQLITE_OK ){ |
+ rc = deleteCell(pRtree, pLeaf, iCell, 0); |
+ } |
+ rc2 = nodeRelease(pRtree, pLeaf); |
+ if( rc==SQLITE_OK ){ |
+ rc = rc2; |
+ } |
+ } |
+ |
+ /* Delete the corresponding entry in the <rtree>_rowid table. */ |
+ if( rc==SQLITE_OK ){ |
+ sqlite3_bind_int64(pRtree->pDeleteRowid, 1, iDelete); |
+ sqlite3_step(pRtree->pDeleteRowid); |
+ rc = sqlite3_reset(pRtree->pDeleteRowid); |
+ } |
+ |
+ /* Check if the root node now has exactly one child. If so, remove |
+ ** it, schedule the contents of the child for reinsertion and |
+ ** reduce the tree height by one. |
+ ** |
+ ** This is equivalent to copying the contents of the child into |
+ ** the root node (the operation that Gutman's paper says to perform |
+ ** in this scenario). |
+ */ |
+ if( rc==SQLITE_OK && pRtree->iDepth>0 && NCELL(pRoot)==1 ){ |
+ int rc2; |
+ RtreeNode *pChild; |
+ i64 iChild = nodeGetRowid(pRtree, pRoot, 0); |
+ rc = nodeAcquire(pRtree, iChild, pRoot, &pChild); |
+ if( rc==SQLITE_OK ){ |
+ rc = removeNode(pRtree, pChild, pRtree->iDepth-1); |
+ } |
+ rc2 = nodeRelease(pRtree, pChild); |
+ if( rc==SQLITE_OK ) rc = rc2; |
+ if( rc==SQLITE_OK ){ |
+ pRtree->iDepth--; |
+ writeInt16(pRoot->zData, pRtree->iDepth); |
+ pRoot->isDirty = 1; |
+ } |
+ } |
+ |
+ /* Re-insert the contents of any underfull nodes removed from the tree. */ |
+ for(pLeaf=pRtree->pDeleted; pLeaf; pLeaf=pRtree->pDeleted){ |
+ if( rc==SQLITE_OK ){ |
+ rc = reinsertNodeContent(pRtree, pLeaf); |
+ } |
+ pRtree->pDeleted = pLeaf->pNext; |
+ sqlite3_free(pLeaf); |
+ } |
+ |
+ /* Release the reference to the root node. */ |
+ if( rc==SQLITE_OK ){ |
+ rc = nodeRelease(pRtree, pRoot); |
+ }else{ |
+ nodeRelease(pRtree, pRoot); |
+ } |
+ } |
+ |
+ /* If the azData[] array contains more than one element, elements |
+ ** (azData[2]..azData[argc-1]) contain a new record to insert into |
+ ** the r-tree structure. |
+ */ |
+ if( rc==SQLITE_OK && nData>1 ){ |
+ /* Insert a new record into the r-tree */ |
+ RtreeCell cell; |
+ int ii; |
+ RtreeNode *pLeaf; |
+ |
+ /* Populate the cell.aCoord[] array. The first coordinate is azData[3]. */ |
+ assert( nData==(pRtree->nDim*2 + 3) ); |
+ if( pRtree->eCoordType==RTREE_COORD_REAL32 ){ |
+ for(ii=0; ii<(pRtree->nDim*2); ii+=2){ |
+ cell.aCoord[ii].f = (float)sqlite3_value_double(azData[ii+3]); |
+ cell.aCoord[ii+1].f = (float)sqlite3_value_double(azData[ii+4]); |
+ if( cell.aCoord[ii].f>cell.aCoord[ii+1].f ){ |
+ rc = SQLITE_CONSTRAINT; |
+ goto constraint; |
+ } |
+ } |
+ }else{ |
+ for(ii=0; ii<(pRtree->nDim*2); ii+=2){ |
+ cell.aCoord[ii].i = sqlite3_value_int(azData[ii+3]); |
+ cell.aCoord[ii+1].i = sqlite3_value_int(azData[ii+4]); |
+ if( cell.aCoord[ii].i>cell.aCoord[ii+1].i ){ |
+ rc = SQLITE_CONSTRAINT; |
+ goto constraint; |
+ } |
+ } |
+ } |
+ |
+ /* Figure out the rowid of the new row. */ |
+ if( sqlite3_value_type(azData[2])==SQLITE_NULL ){ |
+ rc = newRowid(pRtree, &cell.iRowid); |
+ }else{ |
+ cell.iRowid = sqlite3_value_int64(azData[2]); |
+ sqlite3_bind_int64(pRtree->pReadRowid, 1, cell.iRowid); |
+ if( SQLITE_ROW==sqlite3_step(pRtree->pReadRowid) ){ |
+ sqlite3_reset(pRtree->pReadRowid); |
+ rc = SQLITE_CONSTRAINT; |
+ goto constraint; |
+ } |
+ rc = sqlite3_reset(pRtree->pReadRowid); |
+ } |
+ *pRowid = cell.iRowid; |
+ |
+ if( rc==SQLITE_OK ){ |
+ rc = ChooseLeaf(pRtree, &cell, 0, &pLeaf); |
+ } |
+ if( rc==SQLITE_OK ){ |
+ int rc2; |
+ pRtree->iReinsertHeight = -1; |
+ rc = rtreeInsertCell(pRtree, pLeaf, &cell, 0); |
+ rc2 = nodeRelease(pRtree, pLeaf); |
+ if( rc==SQLITE_OK ){ |
+ rc = rc2; |
+ } |
+ } |
+ } |
+ |
+constraint: |
+ rtreeRelease(pRtree); |
+ return rc; |
+} |
+ |
+/* |
+** The xRename method for rtree module virtual tables. |
+*/ |
+static int rtreeRename(sqlite3_vtab *pVtab, const char *zNewName){ |
+ Rtree *pRtree = (Rtree *)pVtab; |
+ int rc = SQLITE_NOMEM; |
+ char *zSql = sqlite3_mprintf( |
+ "ALTER TABLE %Q.'%q_node' RENAME TO \"%w_node\";" |
+ "ALTER TABLE %Q.'%q_parent' RENAME TO \"%w_parent\";" |
+ "ALTER TABLE %Q.'%q_rowid' RENAME TO \"%w_rowid\";" |
+ , pRtree->zDb, pRtree->zName, zNewName |
+ , pRtree->zDb, pRtree->zName, zNewName |
+ , pRtree->zDb, pRtree->zName, zNewName |
+ ); |
+ if( zSql ){ |
+ rc = sqlite3_exec(pRtree->db, zSql, 0, 0, 0); |
+ sqlite3_free(zSql); |
+ } |
+ return rc; |
+} |
+ |
+static sqlite3_module rtreeModule = { |
+ 0, /* iVersion */ |
+ rtreeCreate, /* xCreate - create a table */ |
+ rtreeConnect, /* xConnect - connect to an existing table */ |
+ rtreeBestIndex, /* xBestIndex - Determine search strategy */ |
+ rtreeDisconnect, /* xDisconnect - Disconnect from a table */ |
+ rtreeDestroy, /* xDestroy - Drop a table */ |
+ rtreeOpen, /* xOpen - open a cursor */ |
+ rtreeClose, /* xClose - close a cursor */ |
+ rtreeFilter, /* xFilter - configure scan constraints */ |
+ rtreeNext, /* xNext - advance a cursor */ |
+ rtreeEof, /* xEof */ |
+ rtreeColumn, /* xColumn - read data */ |
+ rtreeRowid, /* xRowid - read data */ |
+ rtreeUpdate, /* xUpdate - write data */ |
+ 0, /* xBegin - begin transaction */ |
+ 0, /* xSync - sync transaction */ |
+ 0, /* xCommit - commit transaction */ |
+ 0, /* xRollback - rollback transaction */ |
+ 0, /* xFindFunction - function overloading */ |
+ rtreeRename /* xRename - rename the table */ |
+}; |
+ |
+static int rtreeSqlInit( |
+ Rtree *pRtree, |
+ sqlite3 *db, |
+ const char *zDb, |
+ const char *zPrefix, |
+ int isCreate |
+){ |
+ int rc = SQLITE_OK; |
+ |
+ #define N_STATEMENT 9 |
+ static const char *azSql[N_STATEMENT] = { |
+ /* Read and write the xxx_node table */ |
+ "SELECT data FROM '%q'.'%q_node' WHERE nodeno = :1", |
+ "INSERT OR REPLACE INTO '%q'.'%q_node' VALUES(:1, :2)", |
+ "DELETE FROM '%q'.'%q_node' WHERE nodeno = :1", |
+ |
+ /* Read and write the xxx_rowid table */ |
+ "SELECT nodeno FROM '%q'.'%q_rowid' WHERE rowid = :1", |
+ "INSERT OR REPLACE INTO '%q'.'%q_rowid' VALUES(:1, :2)", |
+ "DELETE FROM '%q'.'%q_rowid' WHERE rowid = :1", |
+ |
+ /* Read and write the xxx_parent table */ |
+ "SELECT parentnode FROM '%q'.'%q_parent' WHERE nodeno = :1", |
+ "INSERT OR REPLACE INTO '%q'.'%q_parent' VALUES(:1, :2)", |
+ "DELETE FROM '%q'.'%q_parent' WHERE nodeno = :1" |
+ }; |
+ sqlite3_stmt **appStmt[N_STATEMENT]; |
+ int i; |
+ |
+ pRtree->db = db; |
+ |
+ if( isCreate ){ |
+ char *zCreate = sqlite3_mprintf( |
+"CREATE TABLE \"%w\".\"%w_node\"(nodeno INTEGER PRIMARY KEY, data BLOB);" |
+"CREATE TABLE \"%w\".\"%w_rowid\"(rowid INTEGER PRIMARY KEY, nodeno INTEGER);" |
+"CREATE TABLE \"%w\".\"%w_parent\"(nodeno INTEGER PRIMARY KEY, parentnode INTEGER);" |
+"INSERT INTO '%q'.'%q_node' VALUES(1, zeroblob(%d))", |
+ zDb, zPrefix, zDb, zPrefix, zDb, zPrefix, zDb, zPrefix, pRtree->iNodeSize |
+ ); |
+ if( !zCreate ){ |
+ return SQLITE_NOMEM; |
+ } |
+ rc = sqlite3_exec(db, zCreate, 0, 0, 0); |
+ sqlite3_free(zCreate); |
+ if( rc!=SQLITE_OK ){ |
+ return rc; |
+ } |
+ } |
+ |
+ appStmt[0] = &pRtree->pReadNode; |
+ appStmt[1] = &pRtree->pWriteNode; |
+ appStmt[2] = &pRtree->pDeleteNode; |
+ appStmt[3] = &pRtree->pReadRowid; |
+ appStmt[4] = &pRtree->pWriteRowid; |
+ appStmt[5] = &pRtree->pDeleteRowid; |
+ appStmt[6] = &pRtree->pReadParent; |
+ appStmt[7] = &pRtree->pWriteParent; |
+ appStmt[8] = &pRtree->pDeleteParent; |
+ |
+ for(i=0; i<N_STATEMENT && rc==SQLITE_OK; i++){ |
+ char *zSql = sqlite3_mprintf(azSql[i], zDb, zPrefix); |
+ if( zSql ){ |
+ rc = sqlite3_prepare_v2(db, zSql, -1, appStmt[i], 0); |
+ }else{ |
+ rc = SQLITE_NOMEM; |
+ } |
+ sqlite3_free(zSql); |
+ } |
+ |
+ return rc; |
+} |
+ |
+/* |
+** The second argument to this function contains the text of an SQL statement |
+** that returns a single integer value. The statement is compiled and executed |
+** using database connection db. If successful, the integer value returned |
+** is written to *piVal and SQLITE_OK returned. Otherwise, an SQLite error |
+** code is returned and the value of *piVal after returning is not defined. |
+*/ |
+static int getIntFromStmt(sqlite3 *db, const char *zSql, int *piVal){ |
+ int rc = SQLITE_NOMEM; |
+ if( zSql ){ |
+ sqlite3_stmt *pStmt = 0; |
+ rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0); |
+ if( rc==SQLITE_OK ){ |
+ if( SQLITE_ROW==sqlite3_step(pStmt) ){ |
+ *piVal = sqlite3_column_int(pStmt, 0); |
+ } |
+ rc = sqlite3_finalize(pStmt); |
+ } |
+ } |
+ return rc; |
+} |
+ |
+/* |
+** This function is called from within the xConnect() or xCreate() method to |
+** determine the node-size used by the rtree table being created or connected |
+** to. If successful, pRtree->iNodeSize is populated and SQLITE_OK returned. |
+** Otherwise, an SQLite error code is returned. |
+** |
+** If this function is being called as part of an xConnect(), then the rtree |
+** table already exists. In this case the node-size is determined by inspecting |
+** the root node of the tree. |
+** |
+** Otherwise, for an xCreate(), use 64 bytes less than the database page-size. |
+** This ensures that each node is stored on a single database page. If the |
+** database page-size is so large that more than RTREE_MAXCELLS entries |
+** would fit in a single node, use a smaller node-size. |
+*/ |
+static int getNodeSize( |
+ sqlite3 *db, /* Database handle */ |
+ Rtree *pRtree, /* Rtree handle */ |
+ int isCreate /* True for xCreate, false for xConnect */ |
+){ |
+ int rc; |
+ char *zSql; |
+ if( isCreate ){ |
+ int iPageSize; |
+ zSql = sqlite3_mprintf("PRAGMA %Q.page_size", pRtree->zDb); |
+ rc = getIntFromStmt(db, zSql, &iPageSize); |
+ if( rc==SQLITE_OK ){ |
+ pRtree->iNodeSize = iPageSize-64; |
+ if( (4+pRtree->nBytesPerCell*RTREE_MAXCELLS)<pRtree->iNodeSize ){ |
+ pRtree->iNodeSize = 4+pRtree->nBytesPerCell*RTREE_MAXCELLS; |
+ } |
+ } |
+ }else{ |
+ zSql = sqlite3_mprintf( |
+ "SELECT length(data) FROM '%q'.'%q_node' WHERE nodeno = 1", |
+ pRtree->zDb, pRtree->zName |
+ ); |
+ rc = getIntFromStmt(db, zSql, &pRtree->iNodeSize); |
+ } |
+ |
+ sqlite3_free(zSql); |
+ return rc; |
+} |
+ |
+/* |
+** This function is the implementation of both the xConnect and xCreate |
+** methods of the r-tree virtual table. |
+** |
+** argv[0] -> module name |
+** argv[1] -> database name |
+** argv[2] -> table name |
+** argv[...] -> column names... |
+*/ |
+static int rtreeInit( |
+ sqlite3 *db, /* Database connection */ |
+ void *pAux, /* One of the RTREE_COORD_* constants */ |
+ int argc, const char *const*argv, /* Parameters to CREATE TABLE statement */ |
+ sqlite3_vtab **ppVtab, /* OUT: New virtual table */ |
+ char **pzErr, /* OUT: Error message, if any */ |
+ int isCreate /* True for xCreate, false for xConnect */ |
+){ |
+ int rc = SQLITE_OK; |
+ Rtree *pRtree; |
+ int nDb; /* Length of string argv[1] */ |
+ int nName; /* Length of string argv[2] */ |
+ int eCoordType = (pAux ? RTREE_COORD_INT32 : RTREE_COORD_REAL32); |
+ |
+ const char *aErrMsg[] = { |
+ 0, /* 0 */ |
+ "Wrong number of columns for an rtree table", /* 1 */ |
+ "Too few columns for an rtree table", /* 2 */ |
+ "Too many columns for an rtree table" /* 3 */ |
+ }; |
+ |
+ int iErr = (argc<6) ? 2 : argc>(RTREE_MAX_DIMENSIONS*2+4) ? 3 : argc%2; |
+ if( aErrMsg[iErr] ){ |
+ *pzErr = sqlite3_mprintf("%s", aErrMsg[iErr]); |
+ return SQLITE_ERROR; |
+ } |
+ |
+ /* Allocate the sqlite3_vtab structure */ |
+ nDb = strlen(argv[1]); |
+ nName = strlen(argv[2]); |
+ pRtree = (Rtree *)sqlite3_malloc(sizeof(Rtree)+nDb+nName+2); |
+ if( !pRtree ){ |
+ return SQLITE_NOMEM; |
+ } |
+ memset(pRtree, 0, sizeof(Rtree)+nDb+nName+2); |
+ pRtree->nBusy = 1; |
+ pRtree->base.pModule = &rtreeModule; |
+ pRtree->zDb = (char *)&pRtree[1]; |
+ pRtree->zName = &pRtree->zDb[nDb+1]; |
+ pRtree->nDim = (argc-4)/2; |
+ pRtree->nBytesPerCell = 8 + pRtree->nDim*4*2; |
+ pRtree->eCoordType = eCoordType; |
+ memcpy(pRtree->zDb, argv[1], nDb); |
+ memcpy(pRtree->zName, argv[2], nName); |
+ |
+ /* Figure out the node size to use. */ |
+ rc = getNodeSize(db, pRtree, isCreate); |
+ |
+ /* Create/Connect to the underlying relational database schema. If |
+ ** that is successful, call sqlite3_declare_vtab() to configure |
+ ** the r-tree table schema. |
+ */ |
+ if( rc==SQLITE_OK ){ |
+ if( (rc = rtreeSqlInit(pRtree, db, argv[1], argv[2], isCreate)) ){ |
+ *pzErr = sqlite3_mprintf("%s", sqlite3_errmsg(db)); |
+ }else{ |
+ char *zSql = sqlite3_mprintf("CREATE TABLE x(%s", argv[3]); |
+ char *zTmp; |
+ int ii; |
+ for(ii=4; zSql && ii<argc; ii++){ |
+ zTmp = zSql; |
+ zSql = sqlite3_mprintf("%s, %s", zTmp, argv[ii]); |
+ sqlite3_free(zTmp); |
+ } |
+ if( zSql ){ |
+ zTmp = zSql; |
+ zSql = sqlite3_mprintf("%s);", zTmp); |
+ sqlite3_free(zTmp); |
+ } |
+ if( !zSql ){ |
+ rc = SQLITE_NOMEM; |
+ }else if( SQLITE_OK!=(rc = sqlite3_declare_vtab(db, zSql)) ){ |
+ *pzErr = sqlite3_mprintf("%s", sqlite3_errmsg(db)); |
+ } |
+ sqlite3_free(zSql); |
+ } |
+ } |
+ |
+ if( rc==SQLITE_OK ){ |
+ *ppVtab = (sqlite3_vtab *)pRtree; |
+ }else{ |
+ rtreeRelease(pRtree); |
+ } |
+ return rc; |
+} |
+ |
+ |
+/* |
+** Implementation of a scalar function that decodes r-tree nodes to |
+** human readable strings. This can be used for debugging and analysis. |
+** |
+** The scalar function takes two arguments, a blob of data containing |
+** an r-tree node, and the number of dimensions the r-tree indexes. |
+** For a two-dimensional r-tree structure called "rt", to deserialize |
+** all nodes, a statement like: |
+** |
+** SELECT rtreenode(2, data) FROM rt_node; |
+** |
+** The human readable string takes the form of a Tcl list with one |
+** entry for each cell in the r-tree node. Each entry is itself a |
+** list, containing the 8-byte rowid/pageno followed by the |
+** <num-dimension>*2 coordinates. |
+*/ |
+static void rtreenode(sqlite3_context *ctx, int nArg, sqlite3_value **apArg){ |
+ char *zText = 0; |
+ RtreeNode node; |
+ Rtree tree; |
+ int ii; |
+ |
+ UNUSED_PARAMETER(nArg); |
+ memset(&node, 0, sizeof(RtreeNode)); |
+ memset(&tree, 0, sizeof(Rtree)); |
+ tree.nDim = sqlite3_value_int(apArg[0]); |
+ tree.nBytesPerCell = 8 + 8 * tree.nDim; |
+ node.zData = (u8 *)sqlite3_value_blob(apArg[1]); |
+ |
+ for(ii=0; ii<NCELL(&node); ii++){ |
+ char zCell[512]; |
+ int nCell = 0; |
+ RtreeCell cell; |
+ int jj; |
+ |
+ nodeGetCell(&tree, &node, ii, &cell); |
+ sqlite3_snprintf(512-nCell,&zCell[nCell],"%lld", cell.iRowid); |
+ nCell = strlen(zCell); |
+ for(jj=0; jj<tree.nDim*2; jj++){ |
+ sqlite3_snprintf(512-nCell,&zCell[nCell]," %f",(double)cell.aCoord[jj].f); |
+ nCell = strlen(zCell); |
+ } |
+ |
+ if( zText ){ |
+ char *zTextNew = sqlite3_mprintf("%s {%s}", zText, zCell); |
+ sqlite3_free(zText); |
+ zText = zTextNew; |
+ }else{ |
+ zText = sqlite3_mprintf("{%s}", zCell); |
+ } |
+ } |
+ |
+ sqlite3_result_text(ctx, zText, -1, sqlite3_free); |
+} |
+ |
+static void rtreedepth(sqlite3_context *ctx, int nArg, sqlite3_value **apArg){ |
+ UNUSED_PARAMETER(nArg); |
+ if( sqlite3_value_type(apArg[0])!=SQLITE_BLOB |
+ || sqlite3_value_bytes(apArg[0])<2 |
+ ){ |
+ sqlite3_result_error(ctx, "Invalid argument to rtreedepth()", -1); |
+ }else{ |
+ u8 *zBlob = (u8 *)sqlite3_value_blob(apArg[0]); |
+ sqlite3_result_int(ctx, readInt16(zBlob)); |
+ } |
+} |
+ |
+/* |
+** Register the r-tree module with database handle db. This creates the |
+** virtual table module "rtree" and the debugging/analysis scalar |
+** function "rtreenode". |
+*/ |
+int sqlite3RtreeInit(sqlite3 *db){ |
+ const int utf8 = SQLITE_UTF8; |
+ int rc; |
+ |
+ rc = sqlite3_create_function(db, "rtreenode", 2, utf8, 0, rtreenode, 0, 0); |
+ if( rc==SQLITE_OK ){ |
+ rc = sqlite3_create_function(db, "rtreedepth", 1, utf8, 0,rtreedepth, 0, 0); |
+ } |
+ if( rc==SQLITE_OK ){ |
+ void *c = (void *)RTREE_COORD_REAL32; |
+ rc = sqlite3_create_module_v2(db, "rtree", &rtreeModule, c, 0); |
+ } |
+ if( rc==SQLITE_OK ){ |
+ void *c = (void *)RTREE_COORD_INT32; |
+ rc = sqlite3_create_module_v2(db, "rtree_i32", &rtreeModule, c, 0); |
+ } |
+ |
+ return rc; |
+} |
+ |
+/* |
+** A version of sqlite3_free() that can be used as a callback. This is used |
+** in two places - as the destructor for the blob value returned by the |
+** invocation of a geometry function, and as the destructor for the geometry |
+** functions themselves. |
+*/ |
+static void doSqlite3Free(void *p){ |
+ sqlite3_free(p); |
+} |
+ |
+/* |
+** Each call to sqlite3_rtree_geometry_callback() creates an ordinary SQLite |
+** scalar user function. This C function is the callback used for all such |
+** registered SQL functions. |
+** |
+** The scalar user functions return a blob that is interpreted by r-tree |
+** table MATCH operators. |
+*/ |
+static void geomCallback(sqlite3_context *ctx, int nArg, sqlite3_value **aArg){ |
+ RtreeGeomCallback *pGeomCtx = (RtreeGeomCallback *)sqlite3_user_data(ctx); |
+ RtreeMatchArg *pBlob; |
+ int nBlob; |
+ |
+ nBlob = sizeof(RtreeMatchArg) + (nArg-1)*sizeof(double); |
+ pBlob = (RtreeMatchArg *)sqlite3_malloc(nBlob); |
+ if( !pBlob ){ |
+ sqlite3_result_error_nomem(ctx); |
+ }else{ |
+ int i; |
+ pBlob->magic = RTREE_GEOMETRY_MAGIC; |
+ pBlob->xGeom = pGeomCtx->xGeom; |
+ pBlob->pContext = pGeomCtx->pContext; |
+ pBlob->nParam = nArg; |
+ for(i=0; i<nArg; i++){ |
+ pBlob->aParam[i] = sqlite3_value_double(aArg[i]); |
+ } |
+ sqlite3_result_blob(ctx, pBlob, nBlob, doSqlite3Free); |
+ } |
+} |
+ |
+/* |
+** Register a new geometry function for use with the r-tree MATCH operator. |
+*/ |
+int sqlite3_rtree_geometry_callback( |
+ sqlite3 *db, |
+ const char *zGeom, |
+ int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *), |
+ void *pContext |
+){ |
+ RtreeGeomCallback *pGeomCtx; /* Context object for new user-function */ |
+ |
+ /* Allocate and populate the context object. */ |
+ pGeomCtx = (RtreeGeomCallback *)sqlite3_malloc(sizeof(RtreeGeomCallback)); |
+ if( !pGeomCtx ) return SQLITE_NOMEM; |
+ pGeomCtx->xGeom = xGeom; |
+ pGeomCtx->pContext = pContext; |
+ |
+ /* Create the new user-function. Register a destructor function to delete |
+ ** the context object when it is no longer required. */ |
+ return sqlite3_create_function_v2(db, zGeom, -1, SQLITE_ANY, |
+ (void *)pGeomCtx, geomCallback, 0, 0, doSqlite3Free |
+ ); |
+} |
+ |
+#if !SQLITE_CORE |
+int sqlite3_extension_init( |
+ sqlite3 *db, |
+ char **pzErrMsg, |
+ const sqlite3_api_routines *pApi |
+){ |
+ SQLITE_EXTENSION_INIT2(pApi) |
+ return sqlite3RtreeInit(db); |
+} |
+#endif |
+ |
+#endif |