--- /dev/null
-** 2013 Jan 11
+ /*
++** 2016-03-01
+ **
+ ** 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.
+ **
+ *************************************************************************
+ ** Code for testing the virtual table xBestIndex method and the query
+ ** planner.
+ */
+
+
+ /*
+ ** INSTRUCTIONS
+ **
+ ** This module exports a single tcl command - [register_tcl_module]. When
+ ** invoked, it registers a special virtual table module with a database
+ ** connection.
+ **
+ ** The virtual table is currently read-only. And always returns zero rows.
+ ** It is created with a single argument - the name of a Tcl command - as
+ ** follows:
+ **
+ ** CREATE VIRTUAL TABLE x1 USING tcl(tcl_command);
+ **
+ ** The command [tcl_command] is invoked when the table is first created (or
+ ** connected) and when the xBestIndex() method is invoked. When it is created
+ ** (or connected), it is invoked as follows:
+ **
+ ** tcl_command xConnect
+ **
+ ** In this case the return value of the script is passed to the
+ ** sqlite3_declare_vtab() function to create the virtual table schema.
+ **
+ ** When the xBestIndex() method is called by SQLite, the Tcl command is
+ ** invoked as:
+ **
+ ** tcl_command xBestIndex CONSTRAINTS ORDERBY MASK
+ **
+ ** where CONSTRAINTS is a tcl representation of the aConstraints[] array,
+ ** ORDERBY is a representation of the contents of the aOrderBy[] array and
+ ** MASK is a copy of sqlite3_index_info.colUsed. For example if the virtual
+ ** table is declared as:
+ **
+ ** CREATE TABLE x1(a, b, c)
+ **
+ ** and the query is:
+ **
+ ** SELECT * FROM x1 WHERE a=? AND c<? ORDER BY b, c;
+ **
+ ** then the Tcl command is:
+ **
+ ** tcl_command xBestIndex \
+ ** {{op eq column 0 usable 1} {op lt column 2 usable 1}} \
+ ** {{column 1 desc 0} {column 2 desc 0}} \
+ ** 7
+ **
+ ** The return value of the script is a list of key-value pairs used to
+ ** populate the output fields of the sqlite3_index_info structure. Possible
+ ** keys and the usage of the accompanying values are:
+ **
+ ** "orderby" (value of orderByConsumed flag)
+ ** "cost" (value of estimatedCost field)
+ ** "rows" (value of estimatedRows field)
+ ** "use" (index of used constraint in aConstraint[])
+ ** "idxnum" (value of idxNum field)
+ ** "idxstr" (value of idxStr field)
+ **
+ ** Refer to code below for further details.
+ */
+
+
+ #include "sqliteInt.h"
+ #include "tcl.h"
+
+ #ifndef SQLITE_OMIT_VIRTUALTABLE
+
+ typedef struct tcl_vtab tcl_vtab;
+ typedef struct tcl_cursor tcl_cursor;
+
+ /*
+ ** A fs virtual-table object
+ */
+ struct tcl_vtab {
+ sqlite3_vtab base;
+ Tcl_Interp *interp;
+ Tcl_Obj *pCmd;
+ };
+
+ /* A tcl cursor object */
+ struct tcl_cursor {
+ sqlite3_vtab_cursor base;
+ };
+
+ /*
+ ** This function is the implementation of both the xConnect and xCreate
+ ** methods of the fs virtual table.
+ **
+ ** The argv[] array contains the following:
+ **
+ ** argv[0] -> module name ("fs")
+ ** argv[1] -> database name
+ ** argv[2] -> table name
+ ** argv[...] -> other module argument fields.
+ */
+ static int tclConnect(
+ sqlite3 *db,
+ void *pAux,
+ int argc, const char *const*argv,
+ sqlite3_vtab **ppVtab,
+ char **pzErr
+ ){
+ Tcl_Interp *interp = (Tcl_Interp*)pAux;
+ tcl_vtab *pTab;
+ const char *zCmd;
+ Tcl_Obj *pScript = 0;
+ int rc;
+
+ if( argc!=4 ){
+ *pzErr = sqlite3_mprintf("wrong number of arguments");
+ return SQLITE_ERROR;
+ }
+ zCmd = argv[3];
+
+ pTab = (tcl_vtab*)sqlite3_malloc(sizeof(tcl_vtab));
+ if( pTab==0 ) return SQLITE_NOMEM;
+ memset(pTab, 0, sizeof(tcl_vtab));
+
+ pTab->pCmd = Tcl_NewStringObj(zCmd, -1);
+ pTab->interp = interp;
+ Tcl_IncrRefCount(pTab->pCmd);
+
+ pScript = Tcl_DuplicateObj(pTab->pCmd);
+ Tcl_IncrRefCount(pScript);
+ Tcl_ListObjAppendElement(interp, pScript, Tcl_NewStringObj("xConnect", -1));
+
+ rc = Tcl_EvalObjEx(interp, pScript, TCL_EVAL_GLOBAL);
+ if( rc!=TCL_OK ){
+ *pzErr = sqlite3_mprintf("%s", Tcl_GetStringResult(interp));
+ rc = SQLITE_ERROR;
+ }else{
+ rc = sqlite3_declare_vtab(db, Tcl_GetStringResult(interp));
+ }
+
+ if( rc!=SQLITE_OK ){
+ sqlite3_free(pTab);
+ pTab = 0;
+ }
+
+ *ppVtab = &pTab->base;
+ return rc;
+ }
+
+ /* The xDisconnect and xDestroy methods are also the same */
+ static int tclDisconnect(sqlite3_vtab *pVtab){
+ tcl_vtab *pTab = (tcl_vtab*)pVtab;
+ Tcl_DecrRefCount(pTab->pCmd);
+ sqlite3_free(pTab);
+ return SQLITE_OK;
+ }
+
+ /*
+ ** Open a new tcl cursor.
+ */
+ static int tclOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
+ tcl_cursor *pCur;
+ pCur = sqlite3_malloc(sizeof(tcl_cursor));
+ if( pCur==0 ) return SQLITE_NOMEM;
+ memset(pCur, 0, sizeof(tcl_cursor));
+ *ppCursor = &pCur->base;
+ return SQLITE_OK;
+ }
+
+ /*
+ ** Close a tcl cursor.
+ */
+ static int tclClose(sqlite3_vtab_cursor *cur){
+ tcl_cursor *pCur = (tcl_cursor *)cur;
+ sqlite3_free(pCur);
+ return SQLITE_OK;
+ }
+
+ static int tclNext(sqlite3_vtab_cursor *cur){
+ return SQLITE_OK;
+ }
+
+ static int tclFilter(
+ sqlite3_vtab_cursor *pVtabCursor,
+ int idxNum, const char *idxStr,
+ int argc, sqlite3_value **argv
+ ){
+ return SQLITE_OK;
+ }
+
+ static int tclColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
+ return SQLITE_OK;
+ }
+
+ static int tclRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
+ return SQLITE_OK;
+ }
+
+ static int tclEof(sqlite3_vtab_cursor *cur){
+ return 1;
+ }
+
+ static int tclBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
+ tcl_vtab *pTab = (tcl_vtab*)tab;
+ Tcl_Interp *interp = pTab->interp;
+ Tcl_Obj *pArg;
+ Tcl_Obj *pScript;
+ int ii;
+ int rc = SQLITE_OK;
+
+ pScript = Tcl_DuplicateObj(pTab->pCmd);
+ Tcl_IncrRefCount(pScript);
+ Tcl_ListObjAppendElement(interp, pScript, Tcl_NewStringObj("xBestIndex", -1));
+
+ pArg = Tcl_NewObj();
+ Tcl_IncrRefCount(pArg);
+ for(ii=0; ii<pIdxInfo->nConstraint; ii++){
+ struct sqlite3_index_constraint const *pCons = &pIdxInfo->aConstraint[ii];
+ Tcl_Obj *pElem = Tcl_NewObj();
+ const char *zOp = "?";
+
+ Tcl_IncrRefCount(pElem);
+
+ switch( pCons->op ){
+ case SQLITE_INDEX_CONSTRAINT_EQ:
+ zOp = "eq"; break;
+ case SQLITE_INDEX_CONSTRAINT_GT:
+ zOp = "gt"; break;
+ case SQLITE_INDEX_CONSTRAINT_LE:
+ zOp = "le"; break;
+ case SQLITE_INDEX_CONSTRAINT_LT:
+ zOp = "lt"; break;
+ case SQLITE_INDEX_CONSTRAINT_GE:
+ zOp = "ge"; break;
+ case SQLITE_INDEX_CONSTRAINT_MATCH:
+ zOp = "match"; break;
+ case SQLITE_INDEX_CONSTRAINT_LIKE:
+ zOp = "like"; break;
+ case SQLITE_INDEX_CONSTRAINT_GLOB:
+ zOp = "glob"; break;
+ case SQLITE_INDEX_CONSTRAINT_REGEXP:
+ zOp = "regexp"; break;
+ }
+
+ Tcl_ListObjAppendElement(0, pElem, Tcl_NewStringObj("op", -1));
+ Tcl_ListObjAppendElement(0, pElem, Tcl_NewStringObj(zOp, -1));
+ Tcl_ListObjAppendElement(0, pElem, Tcl_NewStringObj("column", -1));
+ Tcl_ListObjAppendElement(0, pElem, Tcl_NewIntObj(pCons->iColumn));
+ Tcl_ListObjAppendElement(0, pElem, Tcl_NewStringObj("usable", -1));
+ Tcl_ListObjAppendElement(0, pElem, Tcl_NewIntObj(pCons->usable));
+
+ Tcl_ListObjAppendElement(0, pArg, pElem);
+ Tcl_DecrRefCount(pElem);
+ }
+
+ Tcl_ListObjAppendElement(0, pScript, pArg);
+ Tcl_DecrRefCount(pArg);
+
+ pArg = Tcl_NewObj();
+ Tcl_IncrRefCount(pArg);
+ for(ii=0; ii<pIdxInfo->nOrderBy; ii++){
+ struct sqlite3_index_orderby const *pOrder = &pIdxInfo->aOrderBy[ii];
+ Tcl_Obj *pElem = Tcl_NewObj();
+ Tcl_IncrRefCount(pElem);
+
+ Tcl_ListObjAppendElement(0, pElem, Tcl_NewStringObj("column", -1));
+ Tcl_ListObjAppendElement(0, pElem, Tcl_NewIntObj(pOrder->iColumn));
+ Tcl_ListObjAppendElement(0, pElem, Tcl_NewStringObj("desc", -1));
+ Tcl_ListObjAppendElement(0, pElem, Tcl_NewIntObj(pOrder->desc));
+
+ Tcl_ListObjAppendElement(0, pArg, pElem);
+ Tcl_DecrRefCount(pElem);
+ }
+
+ Tcl_ListObjAppendElement(0, pScript, pArg);
+ Tcl_DecrRefCount(pArg);
+
+ Tcl_ListObjAppendElement(0, pScript, Tcl_NewWideIntObj(pIdxInfo->colUsed));
+
+ rc = Tcl_EvalObjEx(interp, pScript, TCL_EVAL_GLOBAL);
+ Tcl_DecrRefCount(pScript);
+ if( rc!=TCL_OK ){
+ const char *zErr = Tcl_GetStringResult(interp);
+ rc = SQLITE_ERROR;
+ pTab->base.zErrMsg = sqlite3_mprintf("%s", zErr);
+ }else{
+ /* Analyze the scripts return value. The return value should be a tcl
+ ** list object with an even number of elements. The first element of each
+ ** pair must be one of:
+ **
+ ** "orderby" (value of orderByConsumed flag)
+ ** "cost" (value of estimatedCost field)
+ ** "rows" (value of estimatedRows field)
+ ** "use" (index of used constraint in aConstraint[])
+ ** "idxnum" (value of idxNum field)
+ ** "idxstr" (value of idxStr field)
+ ** "omit" (index of omitted constraint in aConstraint[])
+ */
+ Tcl_Obj *pRes = Tcl_GetObjResult(interp);
+ Tcl_Obj **apElem = 0;
+ int nElem;
+ rc = Tcl_ListObjGetElements(interp, pRes, &nElem, &apElem);
+ if( rc!=TCL_OK ){
+ const char *zErr = Tcl_GetStringResult(interp);
+ rc = SQLITE_ERROR;
+ pTab->base.zErrMsg = sqlite3_mprintf("%s", zErr);
+ }else{
+ int iArgv = 1;
+ for(ii=0; rc==SQLITE_OK && ii<nElem; ii+=2){
+ const char *zCmd = Tcl_GetString(apElem[ii]);
+ Tcl_Obj *p = apElem[ii+1];
+ if( sqlite3_stricmp("cost", zCmd)==0 ){
+ rc = Tcl_GetDoubleFromObj(interp, p, &pIdxInfo->estimatedCost);
+ }else
+ if( sqlite3_stricmp("orderby", zCmd)==0 ){
+ rc = Tcl_GetIntFromObj(interp, p, &pIdxInfo->orderByConsumed);
+ }else
+ if( sqlite3_stricmp("idxnum", zCmd)==0 ){
+ rc = Tcl_GetIntFromObj(interp, p, &pIdxInfo->idxNum);
+ }else
+ if( sqlite3_stricmp("idxstr", zCmd)==0 ){
+ sqlite3_free(pIdxInfo->idxStr);
+ pIdxInfo->idxStr = sqlite3_mprintf("%s", Tcl_GetString(p));
+ pIdxInfo->needToFreeIdxStr = 1;
+ }else
+ if( sqlite3_stricmp("rows", zCmd)==0 ){
+ rc = Tcl_GetWideIntFromObj(interp, p, &pIdxInfo->estimatedRows);
+ }else
+ if( sqlite3_stricmp("use", zCmd)==0
+ || sqlite3_stricmp("omit", zCmd)==0
+ ){
+ int iCons;
+ rc = Tcl_GetIntFromObj(interp, p, &iCons);
+ if( rc==SQLITE_OK ){
+ if( iCons<0 || iCons>=pIdxInfo->nConstraint ){
+ rc = SQLITE_ERROR;
+ pTab->base.zErrMsg = sqlite3_mprintf("unexpected: %d", iCons);
+ }else{
+ int bOmit = (zCmd[0]=='o' || zCmd[0]=='O');
+ pIdxInfo->aConstraintUsage[iCons].argvIndex = iArgv++;
+ pIdxInfo->aConstraintUsage[iCons].omit = bOmit;
+ }
+ }
+ }else{
+ rc = SQLITE_ERROR;
+ pTab->base.zErrMsg = sqlite3_mprintf("unexpected: %s", zCmd);
+ }
+ if( rc!=SQLITE_OK && pTab->base.zErrMsg==0 ){
+ const char *zErr = Tcl_GetStringResult(interp);
+ pTab->base.zErrMsg = sqlite3_mprintf("%s", zErr);
+ }
+ }
+ }
+ }
+
+ return rc;
+ }
+
+ /*
+ ** A virtual table module that provides read-only access to a
+ ** Tcl global variable namespace.
+ */
+ static sqlite3_module tclModule = {
+ 0, /* iVersion */
+ tclConnect,
+ tclConnect,
+ tclBestIndex,
+ tclDisconnect,
+ tclDisconnect,
+ tclOpen, /* xOpen - open a cursor */
+ tclClose, /* xClose - close a cursor */
+ tclFilter, /* xFilter - configure scan constraints */
+ tclNext, /* xNext - advance a cursor */
+ tclEof, /* xEof - check for end of scan */
+ tclColumn, /* xColumn - read data */
+ tclRowid, /* xRowid - read data */
+ 0, /* xUpdate */
+ 0, /* xBegin */
+ 0, /* xSync */
+ 0, /* xCommit */
+ 0, /* xRollback */
+ 0, /* xFindMethod */
+ 0, /* xRename */
+ };
+
+ /*
+ ** Decode a pointer to an sqlite3 object.
+ */
+ extern int getDbPointer(Tcl_Interp *interp, const char *zA, sqlite3 **ppDb);
+
+ /*
+ ** Register the echo virtual table module.
+ */
+ static int register_tcl_module(
+ ClientData clientData, /* Pointer to sqlite3_enable_XXX function */
+ Tcl_Interp *interp, /* The TCL interpreter that invoked this command */
+ int objc, /* Number of arguments */
+ Tcl_Obj *CONST objv[] /* Command arguments */
+ ){
+ sqlite3 *db;
+ if( objc!=2 ){
+ Tcl_WrongNumArgs(interp, 1, objv, "DB");
+ return TCL_ERROR;
+ }
+ if( getDbPointer(interp, Tcl_GetString(objv[1]), &db) ) return TCL_ERROR;
+ #ifndef SQLITE_OMIT_VIRTUALTABLE
+ sqlite3_create_module(db, "tcl", &tclModule, (void *)interp);
+ #endif
+ return TCL_OK;
+ }
+
+ #endif
+
+
+ /*
+ ** Register commands with the TCL interpreter.
+ */
+ int Sqlitetesttcl_Init(Tcl_Interp *interp){
+ #ifndef SQLITE_OMIT_VIRTUALTABLE
+ static struct {
+ char *zName;
+ Tcl_ObjCmdProc *xProc;
+ void *clientData;
+ } aObjCmd[] = {
+ { "register_tcl_module", register_tcl_module, 0 },
+ };
+ int i;
+ for(i=0; i<sizeof(aObjCmd)/sizeof(aObjCmd[0]); i++){
+ Tcl_CreateObjCommand(interp, aObjCmd[i].zName,
+ aObjCmd[i].xProc, aObjCmd[i].clientData, 0);
+ }
+ #endif
+ return TCL_OK;
+ }
projects / thirdparty / sqlite.git / commitdiff
