Add implementations for opcodes required for linear scans of virtual tables. (CVS 3223)

FossilOrigin-Name: 1f20e1832b38c76d2b0dde5fd720670c2ad0438b

src/test8.c

@@ -13,7 +13,7 @@
 ** is not included in the SQLite library.  It is used for automated
 ** testing of the SQLite library.
 **
-** $Id: test8.c,v 1.7 2006/06/13 04:11:44 danielk1977 Exp $
+** $Id: test8.c,v 1.8 2006/06/13 10:24:43 danielk1977 Exp $
 */
 #include "sqliteInt.h"
 #include "tcl.h"
@@ -21,6 +21,24 @@
 #include <stdlib.h>
 #include <string.h>
 
+typedef struct echo_vtab echo_vtab;
+typedef struct echo_cursor echo_cursor;
+
+/* An echo vtab object */
+struct echo_vtab {
+  sqlite3_vtab base;
+  Tcl_Interp *interp;
+  sqlite3 *db;
+  char *zStmt;
+};
+
+/* An echo cursor object */
+struct echo_cursor {
+  sqlite3_vtab_cursor base;
+  sqlite3_stmt *pStmt;
+  int errcode;                 /* Error code */
+};
+
 /*
 ** Global Tcl variable $echo_module is a list. This routine appends
 ** the string element zArg to that list in interpreter interp.
@@ -47,7 +65,12 @@ static void appendToEchoModule(Tcl_Interp *interp, const char *zArg){
 ** Hence, the virtual table should have exactly the same column names and 
 ** types as the real table.
 */
-static int echoDeclareVtab(sqlite3 *db, int argc, char **argv){
+static int echoDeclareVtab(
+  echo_vtab *pVtab, 
+  sqlite3 *db, 
+  int argc, 
+  char **argv
+){
   int rc = SQLITE_OK;
 
   if( argc==2 ){
@@ -65,17 +88,34 @@ static int echoDeclareVtab(sqlite3 *db, int argc, char **argv){
       rc = SQLITE_ERROR;
     }
     sqlite3_finalize(pStmt);
+    pVtab->zStmt = sqlite3MPrintf("SELECT rowid, * FROM %s ", argv[1]);
   }
 
   return rc;
 }
 
-/* An echo vtab object */
-typedef struct echo_vtab echo_vtab;
-struct echo_vtab {
-  sqlite3_vtab base;
-  Tcl_Interp *interp;
-};
+static int echoConstructor(
+  sqlite3 *db,
+  const sqlite3_module *pModule,
+  int argc, char **argv,
+  sqlite3_vtab **ppVtab
+){
+  int i;
+  echo_vtab *pVtab;
+
+  pVtab = sqliteMalloc( sizeof(*pVtab) );
+
+  *ppVtab = &pVtab->base;
+  pVtab->base.pModule = pModule;
+  pVtab->interp = pModule->pAux;
+  pVtab->db = db;
+  for(i=0; i<argc; i++){
+    appendToEchoModule(pVtab->interp, argv[i]);
+  }
+
+  echoDeclareVtab(pVtab, db, argc, argv);
+  return 0;
+}
 
 /* Methods for the echo module */
 static int echoCreate(
@@ -84,20 +124,8 @@ static int echoCreate(
   int argc, char **argv,
   sqlite3_vtab **ppVtab
 ){
-  int i;
-  echo_vtab *pVtab;
-
-  pVtab = sqliteMalloc( sizeof(*pVtab) );
-  *ppVtab = &pVtab->base;
-  pVtab->base.pModule = pModule;
-  pVtab->interp = pModule->pAux;
-  appendToEchoModule(pVtab->interp, "xCreate");
-  for(i=0; i<argc; i++){
-    appendToEchoModule(pVtab->interp, argv[i]);
-  }
-
-  echoDeclareVtab(db, argc, argv);
-  return 0;
+  appendToEchoModule((Tcl_Interp *)(pModule->pAux), "xCreate");
+  return echoConstructor(db, pModule, argc, argv, ppVtab);
 }
 static int echoConnect(
   sqlite3 *db,
@@ -105,35 +133,122 @@ static int echoConnect(
   int argc, char **argv,
   sqlite3_vtab **ppVtab
 ){
-  int i;
-  Tcl_Interp *interp = pModule->pAux;
-  echo_vtab *pVtab;
-
-  pVtab = sqliteMalloc( sizeof(*pVtab) );
-  *ppVtab = &pVtab->base;
-  pVtab->base.pModule = pModule;
-  pVtab->interp = pModule->pAux;
-  appendToEchoModule(pVtab->interp, "xConnect");
-  for(i=0; i<argc; i++){
-    appendToEchoModule(pVtab->interp, argv[i]);
-  }
-
-  echoDeclareVtab(db, argc, argv);
-  return 0;
+  appendToEchoModule((Tcl_Interp *)(pModule->pAux), "xConnect");
+  return echoConstructor(db, pModule, argc, argv, ppVtab);
 }
+
 static int echoDisconnect(sqlite3_vtab *pVtab){
   echo_vtab *p = (echo_vtab*)pVtab;
   appendToEchoModule(p->interp, "xDisconnect");
-  sqliteFree(pVtab);
+  sqliteFree(p->zStmt);
+  sqliteFree(p);
   return 0;
 }
 static int echoDestroy(sqlite3_vtab *pVtab){
   echo_vtab *p = (echo_vtab*)pVtab;
   appendToEchoModule(p->interp, "xDestroy");
-  sqliteFree(pVtab);
+  sqliteFree(p->zStmt);
+  sqliteFree(p);
   return 0;
 }
 
+static int echoOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor)
+{
+  echo_cursor *pCur;
+  pCur = sqliteMalloc(sizeof(echo_cursor));
+  *ppCursor = (sqlite3_vtab_cursor *)pCur;
+  return SQLITE_OK;
+}
+
+static int echoClose(sqlite3_vtab_cursor *cur)
+{
+  echo_cursor *pCur = (echo_cursor *)cur;
+  sqlite3_finalize(pCur->pStmt);
+  sqliteFree(pCur);
+  return SQLITE_OK;
+}
+
+static int echoNext(sqlite3_vtab_cursor *cur)
+{
+  int rc;
+  echo_cursor *pCur = (echo_cursor *)cur;
+
+  rc = sqlite3_step(pCur->pStmt);
+
+  if( rc==SQLITE_ROW ){
+    rc = 1;
+  } else {
+    pCur->errcode = sqlite3_finalize(pCur->pStmt);
+    pCur->pStmt = 0;
+    rc = 0;
+  }
+
+  return rc;
+}
+
+static int echoFilter(
+  sqlite3_vtab_cursor *pVtabCursor, 
+  int idx,
+  int argc, 
+  sqlite3_value **argv
+){
+  int rc;
+
+  echo_cursor *pCur = (echo_cursor *)pVtabCursor;
+  echo_vtab *pVtab = (echo_vtab *)pVtabCursor->pVtab;
+  sqlite3 *db = pVtab->db;
+
+  sqlite3_finalize(pCur->pStmt);
+  pCur->pStmt = 0;
+  rc = sqlite3_prepare(db, pVtab->zStmt, -1, &pCur->pStmt, 0);
+
+  if( rc==SQLITE_OK ){
+    rc = echoNext(pVtabCursor);
+  }
+
+  return rc;
+}
+
+static int echoColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i)
+{
+  int iCol = i + 1;
+  sqlite3_stmt *pStmt = ((echo_cursor *)cur)->pStmt;
+
+  assert( sqlite3_data_count(pStmt)>iCol );
+  switch( sqlite3_column_type(pStmt, iCol) ){
+    case SQLITE_INTEGER:
+      sqlite3_result_int64(ctx, sqlite3_column_int64(pStmt, iCol));
+      break;
+    case SQLITE_FLOAT:
+      sqlite3_result_double(ctx, sqlite3_column_double(pStmt, iCol));
+      break;
+    case SQLITE_TEXT:
+      sqlite3_result_text(ctx, 
+          sqlite3_column_text(pStmt, iCol),
+          sqlite3_column_bytes(pStmt, iCol),
+          SQLITE_TRANSIENT
+      );
+      break;
+    case SQLITE_BLOB:
+      sqlite3_result_blob(ctx, 
+          sqlite3_column_blob(pStmt, iCol),
+          sqlite3_column_bytes(pStmt, iCol),
+          SQLITE_TRANSIENT
+      );
+      break;
+  }
+  return SQLITE_OK;
+}
+
+static int echoRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid)
+{
+  sqlite3_stmt *pStmt = ((echo_cursor *)cur)->pStmt;
+  *pRowid = sqlite3_column_int64(pStmt, 0);
+  return SQLITE_OK;
+}
+
+
+
 /*
 ** The xBestIndex method for the echo module always returns
 ** an index of 123.
@@ -156,6 +271,12 @@ static sqlite3_module echoModule = {
   echoBestIndex,
   echoDisconnect, 
   echoDestroy,
+  echoOpen,                  /* xOpen - open a cursor */
+  echoClose,                 /* xClose - close a cursor */
+  echoFilter,                /* xFilter - configure scan constraints */
+  echoNext,                  /* xNext - advance a cursor */
+  echoColumn,                /* xColumn - read data */
+  echoRowid                  /* xRowid - read data */
 };
 
 /*