/*
** 2006 June 10
**
** 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 interfaces. This code
** is not included in the SQLite library. It is used for automated
** testing of the SQLite library.
*/
/* The code in this file defines a sqlite3 virtual-table module that
** provides a read-only view of the current database schema. There is one
** row in the schema table for each column in the database schema.
*/
#define SCHEMA \
"CREATE TABLE x(" \
"database," /* Name of database (i.e. main, temp etc.) */ \
"tablename," /* Name of table */ \
"cid," /* Column number (from left-to-right, 0 upward) */ \
"name," /* Column name */ \
"type," /* Specified type (i.e. VARCHAR(32)) */ \
"not_null," /* Boolean. True if NOT NULL was specified */ \
"dflt_value," /* Default value for this column */ \
"pk" /* True if this column is part of the primary key */ \
")"
/* If SQLITE_TEST is defined this code is preprocessed for use as part
** of the sqlite test binary "testfixture". Otherwise it is preprocessed
** to be compiled into an sqlite dynamic extension.
*/
#ifdef SQLITE_TEST
#include "sqliteInt.h"
#include "tcl.h"
#else
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#endif
#include <stdlib.h>
#include <string.h>
#include <assert.h>
typedef struct schema_vtab schema_vtab;
typedef struct schema_cursor schema_cursor;
/* A schema table object */
struct schema_vtab {
sqlite3_vtab base;
sqlite3 *db;
};
/* A schema table cursor object */
struct schema_cursor {
sqlite3_vtab_cursor base;
sqlite3_stmt *pDbList;
sqlite3_stmt *pTableList;
sqlite3_stmt *pColumnList;
int rowid;
};
/*
** None of this works unless we have virtual tables.
*/
#ifndef SQLITE_OMIT_VIRTUALTABLE
/*
** Table destructor for the schema module.
*/
static int schemaDestroy(sqlite3_vtab *pVtab){
sqlite3_free(pVtab);
return 0;
}
/*
** Table constructor for the schema module.
*/
static int schemaCreate(
sqlite3 *db,
void *pAux,
int argc, const char *const*argv,
sqlite3_vtab **ppVtab,
char **pzErr
){
int rc = SQLITE_NOMEM;
schema_vtab *pVtab = sqlite3_malloc(sizeof(schema_vtab));
if( pVtab ){
memset(pVtab, 0, sizeof(schema_vtab));
pVtab->db = db;
#ifndef SQLITE_OMIT_VIRTUALTABLE
rc = sqlite3_declare_vtab(db, SCHEMA);
#endif
}
*ppVtab = (sqlite3_vtab *)pVtab;
return rc;
}
/*
** Open a new cursor on the schema table.
*/
static int schemaOpen(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor){
int rc = SQLITE_NOMEM;
schema_cursor *pCur;
pCur = sqlite3_malloc(sizeof(schema_cursor));
if( pCur ){
memset(pCur, 0, sizeof(schema_cursor));
*ppCursor = (sqlite3_vtab_cursor *)pCur;
rc = SQLITE_OK;
}
return rc;
}
/*
** Close a schema table cursor.
*/
static int schemaClose(sqlite3_vtab_cursor *cur){
schema_cursor *pCur = (schema_cursor *)cur;
sqlite3_finalize(pCur->pDbList);
sqlite3_finalize(pCur->pTableList);
sqlite3_finalize(pCur->pColumnList);
sqlite3_free(pCur);
return SQLITE_OK;
}
/*
** Retrieve a column of data.
*/
static int schemaColumn(sqlite3_vtab_cursor *cur, sqlite3_context *ctx, int i){
schema_cursor *pCur = (schema_cursor *)cur;
switch( i ){
case 0:
sqlite3_result_value(ctx, sqlite3_column_value(pCur->pDbList, 1));
break;
case 1:
sqlite3_result_value(ctx, sqlite3_column_value(pCur->pTableList, 0));
break;
default:
sqlite3_result_value(ctx, sqlite3_column_value(pCur->pColumnList, i-2));
break;
}
return SQLITE_OK;
}
/*
** Retrieve the current rowid.
*/
static int schemaRowid(sqlite3_vtab_cursor *cur, sqlite_int64 *pRowid){
schema_cursor *pCur = (schema_cursor *)cur;
*pRowid = pCur->rowid;
return SQLITE_OK;
}
static int finalize(sqlite3_stmt **ppStmt){
int rc = sqlite3_finalize(*ppStmt);
*ppStmt = 0;
return rc;
}
static int schemaEof(sqlite3_vtab_cursor *cur){
schema_cursor *pCur = (schema_cursor *)cur;
return (pCur->pDbList ? 0 : 1);
}
/*
** Advance the cursor to the next row.
*/
static int schemaNext(sqlite3_vtab_cursor *cur){
int rc = SQLITE_OK;
schema_cursor *pCur = (schema_cursor *)cur;
schema_vtab *pVtab = (schema_vtab *)(cur->pVtab);
char *zSql = 0;
while( !pCur->pColumnList || SQLITE_ROW!=sqlite3_step(pCur->pColumnList) ){
if( SQLITE_OK!=(rc = finalize(&pCur->pColumnList)) ) goto next_exit;
while( !pCur->pTableList || SQLITE_ROW!=sqlite3_step(pCur->pTableList) ){
if( SQLITE_OK!=(rc = finalize(&pCur->pTableList)) ) goto next_exit;
assert(pCur->pDbList);
while( SQLITE_ROW!=sqlite3_step(pCur->pDbList) ){
rc = finalize(&pCur->pDbList);
goto next_exit;
}
/* Set zSql to the SQL to pull the list of tables from the
** sqlite_master (or sqlite_temp_master) table of the database
** identified by the row pointed to by the SQL statement pCur->pDbList
** (iterating through a "PRAGMA database_list;" statement).
*/
if( sqlite3_column_int(pCur->pDbList, 0)==1 ){
zSql = sqlite3_mprintf(
"SELECT name FROM sqlite_temp_master WHERE type='table'"
);
}else{
sqlite3_stmt *pDbList = pCur->pDbList;
zSql = sqlite3_mprintf(
"SELECT name FROM %Q.sqlite_master WHERE type='table'",
sqlite3_column_text(pDbList, 1)
);
}
if( !zSql ){
rc = SQLITE_NOMEM;
goto next_exit;
}
rc = sqlite3_prepare(pVtab->db, zSql, -1, &pCur->pTableList, 0);
sqlite3_free(zSql);
if( rc!=SQLITE_OK ) goto next_exit;
}
/* Set zSql to the SQL to the table_info pragma for the table currently
** identified by the rows pointed to by statements pCur->pDbList and
** pCur->pTableList.
*/
zSql = sqlite3_mprintf("PRAGMA %Q.table_info(%Q)",
sqlite3_column_text(pCur->pDbList, 1),
sqlite3_column_text(pCur->pTableList, 0)
);
if( !zSql ){
rc = SQLITE_NOMEM;
goto next_exit;
}
rc = sqlite3_prepare(pVtab->db, zSql, -1, &pCur->pColumnList, 0);
sqlite3_free(zSql);
if( rc!=SQLITE_OK ) goto next_exit;
}
pCur->rowid++;
next_exit:
/* TODO: Handle rc */
return rc;
}
/*
** Reset a schema table cursor.
*/
static int schemaFilter(
sqlite3_vtab_cursor *pVtabCursor,
int idxNum, const char *idxStr,
int argc, sqlite3_value **argv
){
int rc;
schema_vtab *pVtab = (schema_vtab *)(pVtabCursor->pVtab);
schema_cursor *pCur = (schema_cursor *)pVtabCursor;
pCur->rowid = 0;
finalize(&pCur->pTableList);
finalize(&pCur->pColumnList);
finalize(&pCur->pDbList);
rc = sqlite3_prepare(pVtab->db,"PRAGMA database_list", -1, &pCur->pDbList, 0);
return (rc==SQLITE_OK ? schemaNext(pVtabCursor) : rc);
}
/*
** Analyse the WHERE condition.
*/
static int schemaBestIndex(sqlite3_vtab *tab, sqlite3_index_info *pIdxInfo){
return SQLITE_OK;
}
/*
** A virtual table module that merely echos method calls into TCL
** variables.
*/
static sqlite3_module schemaModule = {
0, /* iVersion */
schemaCreate,
schemaCreate,
schemaBestIndex,
schemaDestroy,
schemaDestroy,
schemaOpen, /* xOpen - open a cursor */
schemaClose, /* xClose - close a cursor */
schemaFilter, /* xFilter - configure scan constraints */
schemaNext, /* xNext - advance a cursor */
schemaEof, /* xEof */
schemaColumn, /* xColumn - read data */
schemaRowid, /* xRowid - read data */
0, /* xUpdate */
0, /* xBegin */
0, /* xSync */
0, /* xCommit */
0, /* xRollback */
0, /* xFindMethod */
0, /* xRename */
};
#endif /* !defined(SQLITE_OMIT_VIRTUALTABLE) */
#ifdef SQLITE_TEST
/*
** Decode a pointer to an sqlite3 object.
*/
extern int getDbPointer(Tcl_Interp *interp, const char *zA, sqlite3 **ppDb);
/*
** Register the schema virtual table module.
*/
static int register_schema_module(
ClientData clientData, /* Not used */
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, "schema", &schemaModule, 0);
#endif
return TCL_OK;
}
/*
** Register commands with the TCL interpreter.
*/
int Sqlitetestschema_Init(Tcl_Interp *interp){
static struct {
char *zName;
Tcl_ObjCmdProc *xProc;
void *clientData;
} aObjCmd[] = {
{ "register_schema_module", register_schema_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);
}
return TCL_OK;
}
#else
/*
** Extension load function.
*/
#ifdef _WIN32
__declspec(dllexport)
#endif
int sqlite3_schema_init(
sqlite3 *db,
char **pzErrMsg,
const sqlite3_api_routines *pApi
){
SQLITE_EXTENSION_INIT2(pApi);
#ifndef SQLITE_OMIT_VIRTUALTABLE
sqlite3_create_module(db, "schema", &schemaModule, 0);
#endif
return 0;
}
#endif