SQLite

#include <string.h>
#include <assert.h>

#ifndef SQLITE_AMALGAMATION
#include "sqlite3rtree.h"
typedef sqlite3_int64 i64;
typedef unsigned char u8;
typedef unsigned short u16;
typedef unsigned int u32;
#endif

/*  The following macro is used to suppress compiler warnings.
*/
#ifndef UNUSED_PARAMETER
# define UNUSED_PARAMETER(x) (void)(x)

/* 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 97

/* The xBestIndex method of this virtual table requires an estimate of
** the number of rows in the virtual table to calculate the costs of
** various strategies. If possible, this estimate is loaded from the
** sqlite_stat1 table (with RTREE_MIN_ROWEST as a hard-coded minimum).
** Otherwise, if no sqlite_stat1 entry is available, use 
** RTREE_DEFAULT_ROWEST.
*/
#define RTREE_DEFAULT_ROWEST 1048576
#define RTREE_MIN_ROWEST         100

/* 
** An rtree virtual-table object.
*/
struct Rtree {
  sqlite3_vtab base;          /* Base class.  Must be first */
  sqlite3 *db;                /* Host database connection */
  int iNodeSize;              /* Size in bytes of each node in the node table */
  u8 nDim;                    /* Number of dimensions */
  u8 eCoordType;              /* RTREE_COORD_REAL32 or RTREE_COORD_INT32 */
  u8 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 */ 

  int nBusy;                  /* Current number of users of this structure */
  i64 nRowEst;                /* Estimated number of rows in this table */

  /* 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).

  sqlite3_stmt *pDeleteRowid;

  /* Statements to read/write/delete a record from xxx_parent */
  sqlite3_stmt *pReadParent;
  sqlite3_stmt *pWriteParent;
  sqlite3_stmt *pDeleteParent;

  RtreeNode *aHash[HASHSIZE]; /* Hash table of in-memory nodes. */ 
};

/* Possible values for Rtree.eCoordType: */
#define RTREE_COORD_REAL32 0
#define RTREE_COORD_INT32  1

/*
** If SQLITE_RTREE_INT_ONLY is defined, then this virtual table will
** only deal with integer coordinates.  No floating point operations
** will be done.

*/
#define RTREE_MAX_DEPTH 40

/* 
** An rtree cursor object.
*/
struct RtreeCursor {
  sqlite3_vtab_cursor base;         /* Base class.  Must be first */
  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. */
};

/*
** A coordinate can be either a floating point number or a integer.  All
** coordinates within a single R-Tree are always of the same time.
*/
union RtreeCoord {
  RtreeValue f;      /* Floating point value */
  int i;             /* Integer value */
};

/*
** The argument is an RtreeCoord. Return the value stored within the RtreeCoord
** formatted as a RtreeDValue (double or int64). This macro assumes that local
** variable pRtree points to the Rtree structure associated with the
** RtreeCoord.

#define RTREE_GT    0x45
#define RTREE_MATCH 0x46

/* 
** An rtree structure node.
*/
struct RtreeNode {
  RtreeNode *pParent;          /* Parent node */
  i64 iNode;                   /* The node number */
  int nRef;                    /* Number of references to this node */
  int isDirty;                 /* True if the node needs to be written to disk */
  u8 *zData;                   /* Content of the node, as should be on disk */
  RtreeNode *pNext;            /* Next node in this hash collision chain */
};

/* Return the number of cells in a node  */
#define NCELL(pNode) readInt16(&(pNode)->zData[2])

/* 
** A single cell from a node, deserialized
*/
struct RtreeCell {
  i64 iRowid;                                 /* Node or entry ID */
  RtreeCoord aCoord[RTREE_MAX_DIMENSIONS*2];  /* Bounding box coordinates */
};


/*
** 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).

}

/*
** Given a node number iNode, return the corresponding key to use
** in the Rtree.aHash table.
*/
static int nodeHash(i64 iNode){



  return iNode % 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){

  }
  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;

  return rc;
}

/*
** Overwrite cell iCell of node pNode with the contents of pCell.
*/
static void nodeOverwriteCell(
  Rtree *pRtree,             /* The overall R-Tree */
  RtreeNode *pNode,          /* The node into which the cell is to be written */
  RtreeCell *pCell,          /* The cell to write */
  int iCell                  /* Index into pNode into which pCell is written */
){
  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 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,                /* The overall R-Tree */
  RtreeNode *pNode,             /* Write new cell into this node */
  RtreeCell *pCell              /* The cell to be inserted */
){
  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);

  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;

/*
** 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,       /* The overall R-Tree */
  RtreeNode *pNode,    /* The node from which to extract the ID */
  int iCell            /* The cell index from which to extract the ID */
){
  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,               /* The overall R-Tree */
  RtreeNode *pNode,            /* The node from which to extract a coordinate */
  int iCell,                   /* The index of the cell within the node */
  int iCoord,                  /* Which coordinate to extract */
  RtreeCoord *pCoord           /* OUT: 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,               /* The overall R-Tree */
  RtreeNode *pNode,            /* The node containing the cell to be read */
  int iCell,                   /* Index of the cell within the node */
  RtreeCell *pCell             /* OUT: Write the cell contents here */
){
  int ii;
  pCell->iRowid = nodeGetRowid(pRtree, pNode, iCell);
  for(ii=0; ii<pRtree->nDim*2; ii++){
    nodeGetCoord(pRtree, pNode, iCell, ii, &pCell->aCoord[ii]);
  }
}

    ");",
    nElem, nElem
  );
  speedtest1_run();
  speedtest1_end_test();

}

/* Generate two numbers between 1 and mx.  The first number is less than
** the second.  Usually the numbers are near each other but can sometimes
** be far apart.
*/
static void twoCoords(
  unsigned mx,                      /* Range of 1..mx */
  unsigned *pX0, unsigned *pX1      /* OUT: write results here */
){
  unsigned d, x0, x1, span;

  span = mx/100 + 1;
  if( speedtest1_random()%3==0 ) span *= 3;
  if( speedtest1_random()%17==0 ) span = mx - 5;
  d = speedtest1_random()%span + 1;
  x0 = speedtest1_random()%(mx-d) + 1;
  x1 = x0 + d;
  *pX0 = x0;
  *pX1 = x1;
}

/*
** A testset for the R-Tree virtual table
*/
void testset_rtree(void){
  unsigned i, n;
  unsigned mxCoord;
  unsigned x0, x1, y0, y1, z0, z1;

  mxCoord = g.szTest*600;
  n = g.szTest*100;
  speedtest1_begin_test(100, "%d INSERTs into an r-tree", n);
  speedtest1_exec("BEGIN");
  speedtest1_exec("CREATE VIRTUAL TABLE rt1 USING rtree(id,x0,x1,y0,y1,z0,z1)");
  speedtest1_prepare("INSERT INTO rt1(id,x0,x1,y0,y1,z0,z1)"
                     "VALUES(?1,?2,?3,?4,?5,?6,?7)");
  for(i=1; i<=n; i++){
    twoCoords(mxCoord, &x0, &x1);
    twoCoords(mxCoord, &y0, &y1);
    twoCoords(mxCoord, &z0, &z1);
    sqlite3_bind_int(g.pStmt, 1, i);
    sqlite3_bind_int(g.pStmt, 2, x0);
    sqlite3_bind_int(g.pStmt, 3, x1);
    sqlite3_bind_int(g.pStmt, 4, y0);
    sqlite3_bind_int(g.pStmt, 5, y1);
    sqlite3_bind_int(g.pStmt, 6, z0);
    sqlite3_bind_int(g.pStmt, 7, z1);
    speedtest1_run();
  }
  speedtest1_exec("COMMIT");
  speedtest1_end_test();

  n = g.szTest*20;
  speedtest1_begin_test(110, "%d one-dimensional intersect slice queries", n);
  speedtest1_prepare("SELECT count(*) FROM rt1 WHERE x0>=?1 AND x1<=?2");
  for(i=0; i<mxCoord; i+=(mxCoord/n)){
    sqlite3_bind_int(g.pStmt, 1, i);
    sqlite3_bind_int(g.pStmt, 2, i+mxCoord/n);
    speedtest1_run();
  }
  speedtest1_end_test();

  n = g.szTest*20;
  speedtest1_begin_test(120, "%d one-dimensional overlap slice queries", n);
  speedtest1_prepare("SELECT count(*) FROM rt1 WHERE y1>=?1 AND y0<=?2");
  for(i=0; i<mxCoord; i+=(mxCoord/n)){
    sqlite3_bind_int(g.pStmt, 1, i);
    sqlite3_bind_int(g.pStmt, 2, i+mxCoord/n);
    speedtest1_run();
  }
  speedtest1_end_test();

  n = g.szTest*80;
  speedtest1_begin_test(130, "%d three-dimensional intersect box queries", n);
  speedtest1_prepare("SELECT count(*) FROM rt1 WHERE x1>=?1 AND x0<=?2"
                     " AND y1>=?1 AND y0<=?2 AND z1>=?1 AND z0<=?2");
  for(i=0; i<mxCoord; i+=(mxCoord/n)){
    sqlite3_bind_int(g.pStmt, 1, i);
    sqlite3_bind_int(g.pStmt, 2, i+mxCoord/n);
    speedtest1_run();
  }
  speedtest1_end_test();

  n = g.szTest*100;
  speedtest1_begin_test(140, "%d rowid queries", n);
  speedtest1_prepare("SELECT * FROM rt1 WHERE id=?1");
  for(i=1; i<=n; i++){
    sqlite3_bind_int(g.pStmt, 1, i);
    speedtest1_run();
  }
  speedtest1_end_test();
}

/*
** A testset used for debugging speedtest1 itself.
*/
void testset_debug1(void){
  unsigned i, n;
  unsigned x1, x2;

  if( g.bExplain ) printf(".explain\n.echo on\n");
  if( strcmp(zTSet,"main")==0 ){
    testset_main();
  }else if( strcmp(zTSet,"debug1")==0 ){
    testset_debug1();
  }else if( strcmp(zTSet,"cte")==0 ){
    testset_cte();
  }else if( strcmp(zTSet,"rtree")==0 ){
    testset_rtree();
  }else{
    fatal_error("unknown testset: \"%s\"\nChoices: main debug1 cte rtree\n",
                 zTSet);
  }
  speedtest1_final();

  /* Database connection statistics printed after both prepared statements
  ** have been finalized */
#if SQLITE_VERSION_NUMBER>=3007009
  if( showStats ){