squilu/ext/sq_sqlite3.cpp

/* Code generated by script */
#include "squirrel.h"
#include "sqlite3.h"
#include <string.h>
#include <stdio.h>
#include "sqstdblobimpl.h"

typedef struct sq_sqlite3_sdb sq_sqlite3_sdb;
typedef struct sq_sqlite3_sdb_func sq_sqlite3_sdb_func;

/* to use as C user data so i know what function sqlite is calling */
struct sq_sqlite3_sdb_func {
    /* references to associated lua values */
    HSQOBJECT fn_step;
    HSQOBJECT fn_finalize;
    HSQOBJECT udata;

    sq_sqlite3_sdb *sdb;
    sq_sqlite3_sdb_func *next;
};

/* information about database */
struct sq_sqlite3_sdb {
    /* associated squirrel vm */
    HSQUIRRELVM v;
    /* sqlite database handle */
    sqlite3 *db;

    /* sql functions stack usage */
    sq_sqlite3_sdb_func *func;         /* top SQL function being called */

    /* references */
    HSQOBJECT busy_cb;        /* busy callback */
    HSQOBJECT busy_udata;

    HSQOBJECT progress_cb;    /* progress handler */
    HSQOBJECT progress_udata;

    HSQOBJECT trace_cb;       /* trace callback */
    HSQOBJECT trace_udata;
    HSQOBJECT null_value;
};

SQ_OPT_STRING_STRLEN();

static const SQChar *SQLite3_TAG = "SQLite3";
static const SQChar *SQLite3_Stmt_TAG = "SQLite3Stmt";

static const SQChar sqlite3_NULL_Name[] = _SC("sqlite3_NULL");
static const SQChar nullName[] = _SC("NULL");
static SQRESULT sqlite3_NULL_tostring(HSQUIRRELVM v){
    sq_pushstring(v, "", 0);
    return 1;
}
SQRegFunction sqlite3_NULL_methods[]={
	{_SC("_tostring"),sqlite3_NULL_tostring,1, _SC(".")},
	{0,0}
};

static SQRESULT get_sqlite3_instance(HSQUIRRELVM v, SQInteger idx, sq_sqlite3_sdb **sdb){
    SQRESULT _rc_;
	if((_rc_ = sq_getinstanceup(v,idx,(SQUserPointer*)sdb,(void*)SQLite3_TAG)) < 0) return _rc_;
	if(!*sdb) return sq_throwerror(v, _SC("database is closed"));
	return _rc_;
}

static SQRESULT get_sqlite3_stmt_instance(HSQUIRRELVM v, SQInteger idx, sqlite3_stmt **stmt){
    SQRESULT _rc_;
	if((_rc_ = sq_getinstanceup(v,idx,(SQUserPointer*)stmt,(void*)SQLite3_Stmt_TAG)) < 0) return _rc_;
	if(!*stmt) return sq_throwerror(v, _SC("statement is closed"));
	return _rc_;
}

//#define push_sqlite3_null(v) sq_getonregistrytable(v, sqlite3_NULL_Name, sizeof(sqlite3_NULL_Name)-1);
//#define push_sqlite3_null(v) sq_pushobject(v, sqlite3_NULL);
//#define push_sqlite3_null(v) sq_getbyname(v, 1, nullName, sizeof(nullName)-1)
//#define push_sqlite3_null(v) sq_pushfromregistrytable(v, nullName, sizeof(nullName)-1)
//#define push_sqlite3_null(v) {sq_pushregistrytable(v);sq_pushstring(v, sqlite3_NULL_Name, sizeof(sqlite3_NULL_Name)-1);sq_get(v, -2);sq_remove(v,-2);}
//the line bellow is the fastest one, any other attempt till now was slower
#define push_sqlite3_null(v) {sq_pushstring(v, nullName, sizeof(nullName)-1);sq_get(v, 1);}

#define GET_sqlite3_INSTANCE_AT(idx) \
	sq_sqlite3_sdb *sdb=NULL; \
	if((_rc_ = get_sqlite3_instance(v,idx,&sdb)) < 0) return _rc_;\
	sqlite3 *self = sdb->db;

#define GET_sqlite3_INSTANCE() GET_sqlite3_INSTANCE_AT(1)

//#define GET_sqlite3_INSTANCE() SQ_GET_INSTANCE(v, 1, sqlite3, SQLite3_TAG)
#define GET_sqlite3_stmt_INSTANCE()  \
	sqlite3_stmt *self=NULL; \
	if((_rc_ = get_sqlite3_stmt_instance(v,1,&self)) < 0) return _rc_;

enum e_type_result {tr_first_row_first_col, tr_first_row, tr_all_rows, tr_ddml};

#define AS_STRING_ALWAYS 0x01
#define NULL_AS_EMPTY_STR 0x02

static void sqlite3_stmt_push_string(HSQUIRRELVM v, sqlite3_stmt *stmt, int col, int flags){
    const char *value = (const char*) sqlite3_column_text(stmt, col);
    if(value) sq_pushstring(v, value, sqlite3_column_bytes(stmt, col));
    else push_sqlite3_null(v);
}

static SQRESULT sqlite3_stmt_push_value(HSQUIRRELVM v, sqlite3_stmt *stmt, int col, int flags){
    const char *value;

    if(flags & AS_STRING_ALWAYS) sqlite3_stmt_push_string(v, stmt, col, flags);
    else
    {
        switch (sqlite3_column_type(stmt, col)) {
            case SQLITE_INTEGER:
                {
                    sqlite_int64 i64 = sqlite3_column_int64(stmt, col);
                    SQInteger n = (SQInteger)i64;
                    if (n == i64)
                        sq_pushinteger(v, n);
                    else
                        sq_pushstring(v, (const char*) sqlite3_column_text(stmt, col), sqlite3_column_bytes(stmt, col));
                }
                break;
            case SQLITE_FLOAT:
                sq_pushfloat(v, sqlite3_column_double(stmt, col));
                break;
            case SQLITE_TEXT:
                sqlite3_stmt_push_string(v, stmt, col, flags);
                break;
            case SQLITE_BLOB:
                value = (const char*) sqlite3_column_blob(stmt, col);
                if(value) sq_pushstring(v, value, sqlite3_column_bytes(stmt, col));
                else push_sqlite3_null(v);
                break;
            case SQLITE_NULL:
                push_sqlite3_null(v);
                break;
            default:
                push_sqlite3_null(v);
                break;
        }
    }
    return 1;
}

static void sqlite3_stmt_row_asArray(HSQUIRRELVM v, sqlite3_stmt *stmt, int flags){
    int col_count = sqlite3_column_count(stmt);
    sq_newarray(v, col_count);
    for(int i=0; i<col_count; ++i){
        sq_pushinteger(v, i);
        sqlite3_stmt_push_value(v, stmt, i, flags);
        sq_rawset(v, -3);
    }
}

static void sqlite3_stmt_row_asTable(HSQUIRRELVM v, sqlite3_stmt *stmt, int flags){
    int col_count = sqlite3_column_count(stmt);
    sq_newtable(v);
    for(int i=0; i<col_count; ++i){
        sq_pushstring(v, sqlite3_column_name(stmt, i), -1);
        sqlite3_stmt_push_value(v, stmt, i, flags);
        sq_rawset(v, -3);
    }
}

static void sqlite3_stmt_asArrayOfArrays(HSQUIRRELVM v, sqlite3_stmt *stmt, int flags){
    sq_newarray(v, 0);
    while(sqlite3_step(stmt) == SQLITE_ROW){
        sqlite3_stmt_row_asArray(v, stmt, flags);
        sq_arrayappend(v, -2);
    }
}

static void sqlite3_stmt_asArrayOfTables(HSQUIRRELVM v, sqlite3_stmt *stmt, int flags){
    sq_newarray(v, 0);
    while(sqlite3_step(stmt) == SQLITE_ROW){
        sqlite3_stmt_row_asTable(v, stmt, flags);
        sq_arrayappend(v, -2);
    }
}

static SQRESULT sqlite3_stmt_bind_value(HSQUIRRELVM v, sqlite3_stmt *stmt, int npar, int argn){
    int _rc_ = 0;
    SQObjectType ptype = sq_gettype(v, argn);
    switch(ptype){
        case OT_BOOL:
            SQ_GET_BOOL(v, argn, param_bool);
            _rc_ = sqlite3_bind_int(stmt, npar, param_bool == SQTrue ? 1 : 0);
            break;
        case OT_INTEGER:
            SQ_GET_INTEGER(v, argn, param_integer);
            _rc_ = sqlite3_bind_int64(stmt, npar, param_integer);
            break;
        case OT_FLOAT:
            SQ_GET_FLOAT(v, argn, param_float);
            _rc_ = sqlite3_bind_double(stmt, npar, param_float);
            break;
        case OT_STRING:{
            SQ_GET_STRING(v, argn, param_string);
            _rc_ = sqlite3_bind_text(stmt, npar, param_string, param_string_size, SQLITE_TRANSIENT);
            }
            break;
        case OT_NULL:
            _rc_ = sqlite3_bind_null(stmt, npar);
            break;
        default:
            return sq_throwerror(v, "Invalid bind parameter %d", npar);
    }
    if(_rc_ != SQLITE_OK) {
        sqlite3 *db = sqlite3_db_handle(stmt);
	    return sq_throwerror(v, sqlite3_errmsg(db));
    }
    return SQ_OK;
}

static SQRESULT sq_sqlite3_stmt_prepare_aux(HSQUIRRELVM v, sqlite3 *db, sqlite3_stmt **stmt, int params_start){
    SQ_FUNC_VARS(v);
	SQ_GET_STRING(v, params_start, szSQL);
	const char* szTail=0;
    if(sqlite3_prepare_v2(db, szSQL, szSQL_size, stmt, &szTail) != SQLITE_OK)
    {
        return sq_throwerror(v, sqlite3_errmsg(db));
    }

    if(_top_ > params_start){
        int nparams = sqlite3_bind_parameter_count(*stmt);
        int nparams_given = _top_-params_start;
        if(nparams != nparams_given){
            return sq_throwerror(v, "expect %d parameters but only %d given", nparams, nparams_given);
        }
        for(int i=1; i <= nparams; ++i){
            int argn = i+params_start;
            _rc_ = sqlite3_stmt_bind_value(v, *stmt, i, argn);
            if(_rc_ < 0) return _rc_;
        }
    }
	return SQ_OK;
}

static SQRESULT sq_sqlite3_stmt_releasehook(SQUserPointer p, SQInteger size, HSQUIRRELVM v)
{
	sqlite3_stmt *stmt = ((sqlite3_stmt *)p);
	if(stmt) sqlite3_finalize(stmt);
	return 0;
}

static SQRESULT sq_sqlite3_stmt_constructor(HSQUIRRELVM v)
{
    SQ_FUNC_VARS(v);
    _rc_ = SQ_ERROR;
    GET_sqlite3_INSTANCE_AT(2);
	sqlite3_stmt *stmt = 0;
	if(_top_ > 2){
        _rc_ = sq_sqlite3_stmt_prepare_aux(v, self, &stmt, 3);
	}
	else
	{
        const char* szTail=0;
        if(sqlite3_prepare_v2(self, "select 'statement not prepared';", -1, &stmt, &szTail) != SQLITE_OK)
        {
            _rc_ = sq_throwerror(v, sqlite3_errmsg(self));
        }
        else _rc_ = SQ_OK;
	}
    sq_setinstanceup(v, 1, stmt); //replace self for this instance with this new sqlite3_stmt
    sq_setreleasehook(v,1, sq_sqlite3_stmt_releasehook);
	return _rc_;
}

static SQRESULT sq_sqlite3_stmt_get_db(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	sqlite3 *db = sqlite3_db_handle(self);
	sq_pushuserpointer(v, db);
	if(sq_getonregistrytable(v) == SQ_OK){
	    sq_getweakrefval(v, -1);
	}
	else return sq_throwerror(v, _SC("could not retrive database, maybe it was already closed"));
	return 1;
}

static SQRESULT sq_sqlite3_stmt_finalize(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	if(sqlite3_finalize(self) == SQLITE_OK){
	    sq_setinstanceup(v, 1, 0); //next calls will fail with "statement is closed"
	}
	else {
	    sqlite3 *db = sqlite3_db_handle(self);
	    return sq_throwerror(v, sqlite3_errmsg(db));
	}
	return 0;
}

static SQRESULT sq_sqlite3_stmt_prepare(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	sqlite3 *db = sqlite3_db_handle(self);

	sqlite3_stmt *stmt = 0;
	_rc_ = sq_sqlite3_stmt_prepare_aux(v, db, &stmt, 2);
    if(stmt){
        sqlite3_finalize(self); //finalize the previous sqlite3_stmt
        sq_setinstanceup(v, 1, stmt); //replace self for this instance with this new sqlite3_stmt
    }
	return _rc_;
}

static SQRESULT sq_sqlite3_stmt_get_sql(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	sq_pushstring(v, sqlite3_sql(self), -1);
	return 1;
}

static SQRESULT sq_sqlite3_stmt_bind(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
    SQ_GET_INTEGER(v, 2, npar);
	return sqlite3_stmt_bind_value(v, self, npar, 3);
}

static SQRESULT sq_sqlite3_stmt_bind_parameter_index(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
    SQ_GET_STRING(v, 2, spar);
	sq_pushinteger(v, sqlite3_bind_parameter_index(self, spar));
	return 1;
}

static SQRESULT sq_sqlite3_stmt_reset(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	sq_pushinteger(v, sqlite3_reset(self));
	return 1;
}

static SQRESULT sq_sqlite3_stmt_step(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	sq_pushinteger(v, sqlite3_step(self));
	return 1;
}

static SQRESULT sq_sqlite3_stmt_next_row(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	sq_pushbool(v, sqlite3_step(self) == SQLITE_ROW);
	return 1;
}

static SQRESULT sq_sqlite3_stmt_col_count(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	sq_pushinteger(v, sqlite3_column_count(self));
	return 1;
}

static SQRESULT sq_sqlite3_stmt_colsAsArray(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	int col_count = sqlite3_column_count(self);
	sq_newarray(v, col_count);
	for(int i=0; i<col_count; ++i){
	    sq_pushinteger(v, i);
	    sq_pushstring(v, sqlite3_column_name(self, i), -1);
	    sq_rawset(v, -3);
	}
	return 1;
}

static SQRESULT sq_sqlite3_stmt_colsAsTable(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	int col_count = sqlite3_column_count(self);
	sq_newtable(v);
	for(int i=0; i<col_count; ++i){
	    sq_pushstring(v, sqlite3_column_name(self, i), -1);
	    sq_pushinteger(v, i);
	    sq_rawset(v, -3);
	}
	return 1;
}

static SQRESULT sq_sqlite3_stmt_col_name(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	SQ_GET_INTEGER(v, 2, col);
	sq_pushstring(v, sqlite3_column_name(self, col), -1);
	return 1;
}

static SQRESULT sq_sqlite3_stmt_col_type(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	SQ_GET_INTEGER(v, 2, col);
	sq_pushinteger(v, sqlite3_column_type(self, col));
	return 1;
}

static SQRESULT sq_sqlite3_stmt_col_declared_type(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	SQ_GET_INTEGER(v, 2, col);
	sq_pushstring(v, sqlite3_column_decltype(self, col), -1);
	return 1;
}

static int get_col_index(HSQUIRRELVM v, sqlite3_stmt *self){
	SQInteger _rc_, col;
	switch(sq_gettype(v, 2)){
	    case OT_INTEGER:
            sq_getinteger(v, 2, &col);
	    break;
	    case OT_STRING:{
            SQ_GET_STRING(v, 2, col_name);
            if(col_name_size == 0) return sq_throwerror(v, "column name can not be empty");
            col = -1;
            for(int i=0, len=sqlite3_column_count(self); i<len; ++i){
                if(strcasecmp(col_name, sqlite3_column_name(self, i)) == 0){
                    col = i;
                    break;
                }
            }
            if(col == -1) return sq_throwerror(v, "column name not found \"%s\"", col_name);
	    }
	    break;
	    default:
            return sq_throwerror(v, "wrong parameter expected integer|string");
	}
	return col;
}

static SQRESULT sq_sqlite3_stmt_col(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	int col = get_col_index(v, self);
	if(col < 0) return col;
	sqlite3_stmt_push_value(v, self, col, 0);

	return 1;
}

static SQRESULT sq_sqlite3_stmt_asBool(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	int col = get_col_index(v, self);
	if(col < 0) return col;
    const unsigned char *b = sqlite3_column_text(self, col);
    sq_pushbool(v,  b && *b == '1');

	return 1;
}

static SQRESULT sq_sqlite3_stmt_asInteger(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	int col = get_col_index(v, self);
	if(col < 0) return col;
    sq_pushinteger(v,  sqlite3_column_int64(self, col));

	return 1;
}

static SQRESULT sq_sqlite3_stmt_asFloat(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	int col = get_col_index(v, self);
	if(col < 0) return col;
    sq_pushfloat(v,  sqlite3_column_double(self, col));

	return 1;
}

static SQRESULT sq_sqlite3_stmt_StringOrNull(HSQUIRRELVM v, int withNull){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
	int col = get_col_index(v, self);
	if(col < 0) return col;
	sqlite3_stmt_push_string(v, self, col, withNull ? 0 : NULL_AS_EMPTY_STR);

	return 1;
}

static SQRESULT sq_sqlite3_stmt_asString(HSQUIRRELVM v){
    return sq_sqlite3_stmt_StringOrNull(v, 0);
}

static SQRESULT sq_sqlite3_stmt_asStringOrNull(HSQUIRRELVM v){
    return sq_sqlite3_stmt_StringOrNull(v, 1);
}

static SQRESULT sq_sqlite3_stmt_asTable(HSQUIRRELVM v){
	SQ_FUNC_VARS(v);
	GET_sqlite3_stmt_INSTANCE();
	SQ_OPT_INTEGER(v, 2, flags, 0);
	sqlite3_stmt_row_asTable(v, self, flags);

	return 1;
}

static SQRESULT sq_sqlite3_stmt_asArray(HSQUIRRELVM v){
	SQ_FUNC_VARS(v);
	GET_sqlite3_stmt_INSTANCE();
	SQ_OPT_INTEGER(v, 2, flags, 0);
	sqlite3_stmt_row_asArray(v, self, flags);

	return 1;
}

static SQRESULT sq_sqlite3_stmt_asArrayOfArrays(HSQUIRRELVM v){
	SQ_FUNC_VARS(v);
	GET_sqlite3_stmt_INSTANCE();
	SQ_OPT_INTEGER(v, 2, flags, 0);
	sqlite3_stmt_asArrayOfArrays(v, self, flags);
	sqlite3_reset(self);

	return 1;
}

static SQRESULT sq_sqlite3_stmt_asArrayOfTables(HSQUIRRELVM v){
	SQ_FUNC_VARS(v);
	GET_sqlite3_stmt_INSTANCE();
	SQ_OPT_INTEGER(v, 2, flags, 0);
	sqlite3_stmt_asArrayOfTables(v, self, flags);
	sqlite3_reset(self);

	return 1;
}

/*utility functions*/
static void append_escaping_json(SQBlob &json, const char *sz){
    if(sz){ //escape string
        int last_idx, idx;
        idx = last_idx = 0;
        for(; sz[idx]; ++idx){
            char c = sz[idx];
            switch(c){
                case '"':
                case '\n':
                case '\r':
                case '\\':{
                    json.Write(sz+last_idx, idx-last_idx);
                    last_idx = idx;
                    if(c == '\n') {
                        json.Write("\\n", 2);
                        ++last_idx;
                    }
                    else if(c == '\r'){
                        //skip it
                        ++last_idx;
                    }
                    else
                    {
                        json.Write("\\", 1);
                    }
                }
            }
        }
        //last part
        json.Write(sz+last_idx, idx-last_idx);
    }
}

static SQRESULT sq_sqlite3_stmt_asJsonArray(HSQUIRRELVM v) {
	SQ_FUNC_VARS(v);
	GET_sqlite3_stmt_INSTANCE();
    SQ_OPT_INTEGER(v, 3, withMetadata, 0);
    int col_count = sqlite3_column_count(self);
    int i;
    const char* value;

    SQBlob json(0, 8192);

    if(withMetadata){
        json.WriteZstr("{\n\"columns\":[\n");
        for(i=0; i < col_count; ++i){
            json.WriteZstr((i == 0 ? "\"" : ",\""));
            json.WriteZstr(sqlite3_column_name(self, i));
            json.WriteZstr("\"");
        }

        json.WriteZstr("\n],\n\"column_types\":[\n");
        for(i=0; i < col_count; ++i){
            json.WriteZstr((i == 0 ? "\"" : ",\""));
            json.WriteZstr(sqlite3_column_decltype(self, i));
            json.WriteZstr("\"");
        }

        json.WriteZstr("\n],\n\"rows\":[\n");
    }
    else {
        json.WriteZstr("[\n");
    }
    int row_count = 0;
    while(sqlite3_step(self) == SQLITE_ROW){
        json.WriteZstr((row_count++ == 0 ? "[" : ",["));
        for(i=0; i < col_count; ++i){
            json.WriteZstr((i == 0 ? "\"" : ",\""));
            value = (const char*)sqlite3_column_text(self, i);
            if(value)
            {
                switch(sqlite3_column_type(self, i))
                {
                case SQLITE_TEXT:
                {
                    append_escaping_json(json, value);
                }
                break;
                default:
                    json.WriteZstr(value);
                }
            }
            json.WriteZstr("\"");
        }
        json.WriteZstr("]\n");
    }
    json.WriteZstr("]");
    if(withMetadata) json.WriteZstr("\n}");

    sq_pushstring(v, (const SQChar*)json.GetBuf(), json.Len());
    return 1;
}

static SQRESULT sq_sqlite3_stmt_asJsonObject(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
    int col_count = sqlite3_column_count(self);
    int i;
    const char* value;

    SQBlob json(0, 8192);

    json.WriteZstr("{");
    if(sqlite3_step(self) == SQLITE_ROW){
        for(i=0; i < col_count; ++i){
            json.WriteZstr((i == 0 ? "\"" : "\",\""));
            append_escaping_json(json, (const char*)sqlite3_column_name(self, i));
            json.WriteZstr("\":\"");
            value = (const char*)sqlite3_column_text(self, i);
            if(value)
            {
                switch(sqlite3_column_type(self, i))
                {
                case SQLITE_TEXT:
                {
                    append_escaping_json(json, value);
                }
                break;
                default:
                    json.WriteZstr(value);
                }
            }
        }
        json.WriteZstr("\"");
    }
    json.WriteZstr("}");

    sq_pushstring(v, (const SQChar*)json.GetBuf(), json.Len());
    return 1;
}

#define UNSIGNED(n) n##U
#define IBYTE1 UNSIGNED(255)
#define IBYTE2 UNSIGNED(255*255)
#define IBYTE3 UNSIGNED(255*255*255)
#define IBYTE4 UNSIGNED(255*255*255*255)

#define SIZE1BYTE 250
#define SIZE2BYTE 251
#define SIZE3BYTE 252
#define SIZE4BYTE 253

#define SLEMARK 254
#define SLEEND 255

static SQRESULT sle2array(HSQUIRRELVM v, const unsigned char *p, size_t sle_size, const unsigned char **next)
{
    size_t size, data_count = 1, data_len = 0;

    if(sle_size == 0) {
        *next = 0;
        return 0;
    }

    while(*p != SLEEND) //data finished now follow digest
    {
        size = *p++;
        if(size >= SIZE1BYTE)
        {
            if(size == SIZE1BYTE)
            {
                //data bigger than 250 and less 500 next byte has more info
                size += *p++;
            }
            else if(size == SIZE2BYTE)
            {
                //data bigger than 250 next two bytes has more info
                size = (*p++ * IBYTE1);
                size += *p++;
            }
            else if(size == SIZE3BYTE)
            {
                //data bigger than 250 next three bytes has more info
                size = (*p++ * IBYTE2);
                size += (*p++ * IBYTE1);
                size += *p++;
            }
            else if(size == SIZE4BYTE)
            {
                //data bigger than 250 next four bytes has more info
                size = (*p++ * IBYTE3);
                size += (*p++ * IBYTE2);
                size += (*p++ * IBYTE1);
                size += *p++;
            }
            else if(size == SLEMARK)
            {
                //reserved can be used for multi part data, metadata, digest, ...
                break;
            }
        }

        sq_pushstring(v, (const char*)p, size);
        sq_arrayappend(v, -2);
        p += size;
        data_len += size;
        if(data_len > sle_size)
        {
            //something went wrong here
            return sq_throwerror(v, "We got more data than expected !");
        }
    }
    *next = ++p;
    return 0;
}

static SQRESULT sle2vec(HSQUIRRELVM v, const unsigned char *sle,
                                         size_t sle_size,
                                         const unsigned char **next)
{
    int rc;
    sq_newarray(v, 0);
    if(sle[0] != '[') {
        return sq_throwerror(v, "Invalid encoded vector !");
    }
    if(sle[1] == ']') {
        *next = sle+2; //empty array
        return 0;
    }
    if((rc = sle2array(v, sle+1, sle_size-1, next)) < 0) return rc;
    if(!*next || *next[0] != ']'){
        return sq_throwerror(v, "Invalid end of vector !");
    }
    *next++;
    return 0;
}

static SQRESULT sle2vecOfvec(HSQUIRRELVM v)
{
    SQ_FUNC_VARS(v);
    SQ_GET_STRING(v, 2, sle);
    SQ_OPT_INTEGER(v, 3, start, 0);

    int rc, data_count = 1;

    sq_newarray(v, 0);
    const unsigned char *next;
    if(sle[0] != '[') {
        return sq_throwerror(v, "Invalid encoded vector !");
    }
    if(sle[1] == ']') {
        //sq_pushinteger(v, start+2);
        return 1; //empty array
    }
    int saved_top = sq_gettop(v);
    if((rc=sle2vec(v, (const unsigned char *)sle+1, sle_size-1, &next)) < 0) return rc;
    while(next && *next == '['){
        sq_arrayappend(v, -2);
        data_count++;
        if((rc=sle2vec(v, next, sle_size - (next - (const unsigned char *)sle), &next)) < 0) return rc;
    }
    if(sq_gettop(v) != saved_top){
        //last added table left
        sq_arrayappend(v, -2);
        data_count++;
    }
    if(!next || *next != ']'){
        return sq_throwerror(v, "Invalid end of vector !");
    }
    //sq_pushinteger(v, ++next - sle);
    return 1;
}

typedef unsigned char slebuf_t[8];

static int sleSize2buf(slebuf_t sle, size_t size){
    size_t next_size, tmp_size;
    if(size < SIZE1BYTE)
    {
        sle[0] = size;
        return 1;
    }
    else if(size < (SIZE1BYTE*2))
    {
        sle[0] = SIZE1BYTE;
        next_size = size - 250;
        sle[1] = next_size;
        return 2;
    }
    else if(size < IBYTE2)
    {
        sle[0] = SIZE2BYTE;
        next_size = size/IBYTE1;
        sle[1] = next_size;
        next_size = size%IBYTE1;
        sle[2] = next_size;
        return 3;
    }
    else if(size < IBYTE3)
    {
        sle[0] = SIZE3BYTE;
        next_size = size/IBYTE2;
        sle[1] = next_size;
        tmp_size = size%IBYTE2;
        next_size = tmp_size/IBYTE1;
        sle[2] = next_size;
        next_size = tmp_size%IBYTE1;
        sle[3] = next_size;
        return 4;
    }
    else if(size < IBYTE4)
    {
        sle[0] = SIZE4BYTE;
        next_size = size/IBYTE3;
        sle[1] = next_size;
        tmp_size = size%IBYTE3;
        next_size = tmp_size/IBYTE2;
        sle[2] = next_size;
        tmp_size = tmp_size%IBYTE2;
        next_size = tmp_size/IBYTE1;
        sle[3] = next_size;
        next_size = tmp_size%IBYTE1;
        sle[5] = next_size;
        return 5;
    }
    return 0;
}

static SQRESULT get_sle_size(HSQUIRRELVM v){
    SQ_FUNC_VARS_NO_TOP(v);
    slebuf_t slebuf;
    SQ_GET_INTEGER(v, 2, size);
    int slesize = sleSize2buf(slebuf, size);
    if(slesize) {
        sq_pushstring(v, (const char *)slebuf, slesize);
        return 1;
    }
    return 0;
}

static int add2sle(SQBlob &sle, const char *str, size_t size){
    slebuf_t slebuf;
    int slesize = sleSize2buf(slebuf, size);
    if(slesize) sle.Write((const char *)slebuf, slesize);
    if(size) sle.Write(str, size);
    return size;
}

static SQRESULT sq_sqlite3_stmt_asSleArray(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_stmt_INSTANCE();
    int col_count = sqlite3_column_count(self);
    int i;
    const char *value;

    SQBlob sle(0, 8192);

    sle.WriteZstr("[[");
    for(i=0; i < col_count; ++i){
        value = sqlite3_column_name(self, i);
        add2sle(sle, value, strlen(value));
    }
    sle.WriteChar(SLEEND);
    sle.WriteChar(']');

    while(sqlite3_step(self) == SQLITE_ROW){
        sle.WriteChar('[');
        for(i=0; i < col_count; ++i){
            switch(sqlite3_column_type(self, i))
            {
            case SQLITE_BLOB:
            {
                add2sle(sle, (const char*)sqlite3_column_blob(self, i),
                                sqlite3_column_bytes(self, i));
            }
            break;
            default:
                add2sle(sle, (const char*)sqlite3_column_text(self, i),
                                sqlite3_column_bytes(self, i));
            }
        }
        sle.WriteChar(SLEEND);
        sle.WriteChar(']');
    }
    sle.WriteChar(']');

    sq_pushstring(v, (const SQChar*)sle.GetBuf(), sle.Len());
    return 1;
}

#define _DECL_FUNC(name,nparams,tycheck) {_SC(#name),  sq_sqlite3_stmt_##name,nparams,tycheck}
static SQRegFunction sq_sqlite3_stmt_methods[] =
{
	_DECL_FUNC(constructor,  -2, _SC("xxs s|n|b|o")),

	_DECL_FUNC(get_db,  1, _SC("x")),
	_DECL_FUNC(finalize,  1, _SC("x")),
	_DECL_FUNC(prepare,  -2, _SC("xs s|n|b|o")),
	_DECL_FUNC(get_sql,  1, _SC("x")),
	_DECL_FUNC(bind,  3, _SC("xi s|n|b|o")),
	_DECL_FUNC(bind_parameter_index,  2, _SC("xs")),
	_DECL_FUNC(step,  1, _SC("x")),
	_DECL_FUNC(reset,  1, _SC("x")),
	_DECL_FUNC(next_row,  1, _SC("x")),
	_DECL_FUNC(colsAsArray,  1, _SC("x")),
	_DECL_FUNC(colsAsTable,  1, _SC("x")),
	_DECL_FUNC(col_count,  1, _SC("x")),
	_DECL_FUNC(col_name,  2, _SC("xi")),
	_DECL_FUNC(col_type,  2, _SC("xi")),
	_DECL_FUNC(col_declared_type,  2, _SC("xi")),
	_DECL_FUNC(asArray,  -1, _SC("xi")),
	_DECL_FUNC(asTable,  -1, _SC("xi")),
	_DECL_FUNC(asArrayOfArrays,  -1, _SC("xi")),
	_DECL_FUNC(asArrayOfTables,  -1, _SC("xi")),
	_DECL_FUNC(col,  2, _SC("x i|s")),
	_DECL_FUNC(asString,  2, _SC("x i|s")),
	_DECL_FUNC(asStringOrNull, 2, _SC("x i|s")),
	_DECL_FUNC(asInteger,  2, _SC("x i|s")),
	_DECL_FUNC(asBool,  2, _SC("x i|s")),
	_DECL_FUNC(asFloat,  2, _SC("x i|s")),
	{0,0}
};
#undef _DECL_FUNC

static SQRESULT sqlite3_exec_fmt(HSQUIRRELVM v, e_type_result type_result, int null_as_empty_str=1){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
	SQ_GET_STRING(v, 2, szSQL);
	sqlite3_stmt *stmt = 0;
	_rc_ = sq_sqlite3_stmt_prepare_aux(v, self, &stmt, 2);
    if(_rc_ < 0){
        if(stmt) sqlite3_finalize(stmt);
        return _rc_;
    }

    int rc = sqlite3_step(stmt);

    if(type_result == tr_ddml) {
        if(rc != SQLITE_DONE) {
            sqlite3_finalize(stmt);
            return sq_throwerror(v, "SQL is not a DDML %d %s", rc, sqlite3_errmsg(self));
        }
        sq_pushinteger(v, sqlite3_changes(sqlite3_db_handle(stmt)));
    }
    else
    {
        if(rc != SQLITE_ROW) {
            sqlite3_finalize(stmt);
            return sq_throwerror(v, "%d %s", rc, sqlite3_errmsg(self));
        }
        switch(type_result){
            case tr_first_row_first_col:
                sqlite3_stmt_push_value(v, stmt, 0, 0);
            break;
            case tr_first_row:
                sqlite3_stmt_row_asArray(v, stmt, NULL_AS_EMPTY_STR|AS_STRING_ALWAYS);
            break;
            case tr_all_rows:
                sqlite3_stmt_asArrayOfArrays(v, stmt, NULL_AS_EMPTY_STR|AS_STRING_ALWAYS);
            break;
            default:
                sqlite3_finalize(stmt);
                return sq_throwerror(v, "Unknown requested return type %d", type_result);
        }
    }
    sqlite3_finalize(stmt);
	return 1;
}


static SQRESULT sq_sqlite3_close_release(HSQUIRRELVM v, sq_sqlite3_sdb *sdb){
    SQRESULT rc = SQ_ERROR;
	if(sdb){
        if(sqlite3_close_v2(sdb->db) == SQLITE_OK){
            rc = SQ_OK;

            //remove waekref from registrytable
            sq_pushregistrytable(sdb->v);
            sq_pushuserpointer(sdb->v, sdb->db);
            sq_deleteslot(sdb->v, -2, SQFalse);
            sq_poptop(sdb->v);

	if(sdb->func){
        sq_sqlite3_sdb_func *func, *func_next;
        func = sdb->func;
        while (func) {
            func_next = func->next;
            sq_release(sdb->v, &func->fn_step);
            sq_release(sdb->v, &func->fn_finalize);
            sq_release(sdb->v, &func->udata);
            sq_free(func, sizeof(sq_sqlite3_sdb_func));
            func = func_next;
        }
        sdb->func = NULL;
	}
    /* 'free' all references */
    sq_release(sdb->v, &sdb->busy_cb);
    sq_release(sdb->v, &sdb->busy_udata);
    sq_release(sdb->v, &sdb->progress_cb);
    sq_release(sdb->v, &sdb->progress_udata);
    sq_release(sdb->v, &sdb->trace_cb);
    sq_release(sdb->v, &sdb->trace_udata);
    sq_release(sdb->v, &sdb->null_value);

	sq_free(sdb, sizeof(sq_sqlite3_sdb));
	}
	}
	return rc;
}

static SQRESULT sq_sqlite3_releasehook(SQUserPointer p, SQInteger size, HSQUIRRELVM v)
{
	sq_sqlite3_sdb *sdb = ((sq_sqlite3_sdb *)p);
	sq_sqlite3_close_release(v, sdb);
	return 0;
}

static SQRESULT sq_sqlite3_constructor(HSQUIRRELVM v)
{
    SQ_FUNC_VARS(v);
    SQ_GET_STRING(v, 2, dbname);
    SQ_OPT_INTEGER(v, 3, flags, SQLITE_OPEN_CREATE | SQLITE_OPEN_READWRITE | SQLITE_OPEN_SHAREDCACHE | SQLITE_OPEN_SUBLATIN_NA_LIKE);
    sqlite3 *db;
    int rc = sqlite3_open_v2(dbname, &db, flags, 0);
    if(rc != SQLITE_OK) return sq_throwerror(v, "Failed to open database ! %d", rc);

    sq_sqlite3_sdb *sdb = (sq_sqlite3_sdb *)sq_malloc(sizeof(sq_sqlite3_sdb));
    memset(sdb, 0, sizeof(sq_sqlite3_sdb));
    sdb->db = db;
    sdb->v = v;
    sq_resetobject(&sdb->busy_cb);
    sq_resetobject(&sdb->busy_udata);
    sq_resetobject(&sdb->progress_cb);
    sq_resetobject(&sdb->progress_udata);
    sq_resetobject(&sdb->trace_cb);
    sq_resetobject(&sdb->trace_udata);

    sq_setinstanceup(v, 1, sdb);
    sq_setreleasehook(v,1, sq_sqlite3_releasehook);

    //save a weakref to allow statement return it's db
    sq_pushuserpointer(v, sdb->db);
    sq_weakref(v, 1);
    sq_setonregistrytable(v);

    return 1;
}

static SQRESULT sq_sqlite3_close(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
	if(sq_sqlite3_close_release(v, sdb) == SQ_OK){
	    sq_setinstanceup(v, 1, 0); //next calls will fail with "database is closed"
	}
	else {
	    return sq_throwerror(v, sqlite3_errmsg(self));
	}
	return 0;
}

/* bool IsAutoCommitOn(  ) */
static SQRESULT sq_sqlite3_IsAutoCommitOn(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
	sq_pushbool(v, sqlite3_get_autocommit(self) ? SQTrue : SQFalse);
	return 1;
}

/* int changes(  ) */
static SQRESULT sq_sqlite3_changes(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
	sq_pushinteger(v, sqlite3_total_changes(self));
	return 1;
}

static SQRESULT sq_sqlite3_exec(HSQUIRRELVM v){
    return sqlite3_exec_fmt(v, tr_all_rows);
}

/* int exec_dml( const char * szSQL  ) */
static SQRESULT sq_sqlite3_exec_dml(HSQUIRRELVM v){
    return sqlite3_exec_fmt(v, tr_ddml);
}

/* bool exec_get_one( std::string & result  , const char * szSQL  ) */
static SQRESULT sq_sqlite3_exec_get_one(HSQUIRRELVM v){
    return sqlite3_exec_fmt(v, tr_first_row_first_col);
}

static SQRESULT sq_sqlite3_exec_get_first_row(HSQUIRRELVM v){
    return sqlite3_exec_fmt(v, tr_first_row);
}

/* const char * get_db_name(  ) */
static SQRESULT sq_sqlite3_get_db_name(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
	sq_pushstring(v, sqlite3_db_filename(self, "main"), -1);
	return 1;
}

/* sqlite3_int64 last_row_id(  ) */
static SQRESULT sq_sqlite3_last_row_id(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
	sq_pushinteger(v, sqlite3_last_insert_rowid(self));
	return 1;
}

/* stmt * prepare( const char * sql  ) */
static SQRESULT sq_sqlite3_prepare(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
	SQ_GET_STRING(v, 2, sql);
	sq_pushstring(v, SQLite3_Stmt_TAG, -1);
	if(sq_getonroottable(v) == SQ_ERROR) return SQ_ERROR;
	sq_pushroottable(v);
	sq_push(v, 1);
	sq_push(v, 2);
	if(sq_call(v, 3, SQTrue, SQFalse) != SQ_OK) return SQ_ERROR;
	return 1;
}

/* void set_busy_timeout( int nMillisecs  ) */
static SQRESULT sq_sqlite3_set_busy_timeout(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
	SQ_GET_INTEGER(v, 2, nMillisecs);
	//self->set_busy_timeout(nMillisecs);
	return 0;
}

/* int total_changes(  ) */
static SQRESULT sq_sqlite3_total_changes(HSQUIRRELVM v){
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
	sq_pushinteger(v, sqlite3_total_changes(self));
	return 1;
}

static SQRESULT sq_sqlite3_enable_shared_cache(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	SQ_GET_BOOL(v, 2, bhow);
    sq_pushbool(v, sqlite3_enable_shared_cache(bhow) == SQLITE_OK);
    return 1;
}

static SQRESULT sq_sqlite3_sleep(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	SQ_GET_INTEGER(v, 2, n);
    sqlite3_sleep(n);
    return 0;
}

static SQRESULT sq_sqlite3_version(HSQUIRRELVM v) {
    sq_pushstring(v, sqlite3_libversion(), -1);
    return 1;
}

static SQRESULT sq_sqlite3_errcode(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
    sq_pushinteger(v, sqlite3_errcode(self));
    return 1;
}

static SQRESULT sq_sqlite3_errmsg(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
    sq_pushstring(v, sqlite3_errmsg(self), -1);
    return 1;
}

#ifndef WIN32
static SQRESULT sq_sqlite3_temp_directory(HSQUIRRELVM v) {
    SQ_FUNC_VARS(v);
    const char *oldtemp = sqlite3_temp_directory;

    if (_top_ > 1) {
        SQ_GET_STRING(v, 2, temp);
        if (sqlite3_temp_directory) {
            sqlite3_free((char*)sqlite3_temp_directory);
        }
        if (temp && temp_size) {
            sqlite3_temp_directory = sqlite3_mprintf("%s", temp);
        }
        else {
            sqlite3_temp_directory = NULL;
        }
    }
    sq_pushstring(v, oldtemp, -1);
    return 1;
}
#endif

#ifdef SQLITE_HAS_CODEC

//#include "codecext.h"
/*
** Params: db, sql
** returns: code, compiled length or error message
*/
static SQRESULT sq_sqlite3_key(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
	SQ_GET_STRING(v, 2, key);
    sq_pushinteger(v, sqlite3_key(self, key, key_size));
    return 1;
}

/*
** Params: db, sql
** returns: code, compiled length or error message
*/
static SQRESULT sq_sqlite3_rekey(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
	SQ_GET_STRING(v, 2, key);
    sq_pushinteger(v, sqlite3_rekey(self, key, key_size));
    return 1;
}

#endif

#if !defined(SQLITE_OMIT_PROGRESS_CALLBACK) || !SQLITE_OMIT_PROGRESS_CALLBACK

/*
** progress handler:
** Params: database, number of opcodes, callback function, userdata
**
** callback function:
** Params: userdata
** returns: 0 to return immediatly and return SQLITE_ABORT, non-zero to continue
*/
static int db_progress_callback(void *user) {
    int result = 1; /* abort by default */
    sq_sqlite3_sdb *sdb = (sq_sqlite3_sdb*)user;
    HSQUIRRELVM v = sdb->v;
    int top = sq_gettop(v);

    sq_pushobject(v, sdb->progress_cb);
    sq_pushroottable(v); //this
    sq_pushobject(v, sdb->progress_udata);

    /* call lua function */
    if (sq_call(v, 2, SQTrue, SQFalse) == SQ_OK)
        sq_getinteger(v, -1, &result);

    sq_settop(v, top);
    return result;
}

static SQRESULT sq_sqlite3_progress_handler(HSQUIRRELVM v) {
	SQ_FUNC_VARS(v);
	GET_sqlite3_INSTANCE();

    if (_top_ < 2 || sq_gettype(v, 2) == OT_NULL) {
        sq_release(v, &sdb->progress_cb);
        sq_release(v, &sdb->progress_udata);

        sq_resetobject(&sdb->progress_cb);
        sq_resetobject(&sdb->progress_udata);

        /* clear busy handler */
        sqlite3_progress_handler(self, 0, NULL, NULL);
    }
    else {
        SQ_GET_INTEGER(v, 2, nop);
        if(sq_gettype(v, 3) != OT_CLOSURE)
            return sq_throwerror(v, _SC("invalid second parameter expected closure"));

        sq_getstackobj(v, 3, &sdb->progress_cb);
        sq_addref(v, &sdb->progress_cb);
        if(_top_ > 3){
            sq_getstackobj(v, 4, &sdb->progress_udata);
            sq_addref(v, &sdb->progress_udata);
        }

        /* set progress callback */
        sqlite3_progress_handler(self, nop, db_progress_callback, sdb);
    }

    return 0;
}

#else /* #if !defined(SQLITE_OMIT_PROGRESS_CALLBACK) || !SQLITE_OMIT_PROGRESS_CALLBACK */

static SQRESULT sq_sqlite3_progress_handler(HSQUIRRELVM v) {
    return sq_throwerror(v, _SC("progress callback support disabled at compile time"));
    return 0;
}

#endif /* #if !defined(SQLITE_OMIT_PROGRESS_CALLBACK) || !SQLITE_OMIT_PROGRESS_CALLBACK */

/*
** trace callback:
** Params: database, callback function, userdata
**
** callback function:
** Params: userdata, sql
*/
static void db_trace_callback(void *user, const char *sql) {
    sq_sqlite3_sdb *sdb = (sq_sqlite3_sdb*)user;
    HSQUIRRELVM v = sdb->v;
    int top = sq_gettop(v);

    /* setup squirrel callback call */
    sq_pushobject(v, sdb->trace_cb);
    sq_pushroottable(v);
    sq_pushobject(v, sdb->trace_udata);
    sq_pushstring(v, sql, -1); /* traced sql statement */

    /* call squirrel function */
    sq_call(v, 3, SQFalse, SQFalse);
    /* ignore any error generated by this function */

    sq_settop(v, top);
}

static SQRESULT sq_sqlite3_trace(HSQUIRRELVM v) {
	SQ_FUNC_VARS(v);
	GET_sqlite3_INSTANCE();

    if (_top_ < 2 || sq_gettype(v, 2) == OT_NULL) {
        sq_release(v, &sdb->trace_cb);
        sq_release(v, &sdb->trace_udata);

        sq_resetobject(&sdb->trace_cb);
        sq_resetobject(&sdb->trace_udata);

        /* clear trace handler */
        sqlite3_trace(self, NULL, NULL);
    }
    else {
        if(sq_gettype(v, 2) != OT_CLOSURE)
            return sq_throwerror(v, _SC("invalid fisrt parameter expected closure"));

        sq_getstackobj(v, 2, &sdb->trace_cb);
        sq_addref(v, &sdb->trace_cb);
        if(_top_ > 2){
            sq_getstackobj(v, 3, &sdb->trace_udata);
            sq_addref(v, &sdb->trace_udata);
        }

        /* set trace callback */
        sqlite3_trace(self, db_trace_callback, sdb);
    }

    return 0;
}

/*
** busy handler:
** Params: database, callback function, userdata
**
** callback function:
** Params: userdata, number of tries
** returns: 0 to return immediatly and return SQLITE_BUSY, non-zero to try again
*/
static int db_busy_callback(void *user, int tries) {
    SQBool retry = SQFalse; /* abort by default */
    sq_sqlite3_sdb *sdb = (sq_sqlite3_sdb*)user;
    HSQUIRRELVM v = sdb->v;
    int top = sq_gettop(v);

    sq_pushobject(v, sdb->busy_cb);
    sq_pushroottable(v);
    sq_pushobject(v, sdb->busy_udata);
    sq_pushinteger(v, tries);

    /* call lua function */
    if (sq_call(v, 3, SQTrue, SQFalse) == SQ_OK)
        sq_getbool(v, -1, &retry);

    sq_settop(v, top);
    return retry == SQTrue;
}

static SQRESULT sq_sqlite3_busy_handler(HSQUIRRELVM v) {
	SQ_FUNC_VARS(v);
	GET_sqlite3_INSTANCE();

    if (_top_ < 2 || sq_gettype(v, 2) == OT_NULL) {
        sq_release(v, &sdb->busy_cb);
        sq_release(v, &sdb->busy_udata);

        sq_resetobject(&sdb->busy_cb);
        sq_resetobject(&sdb->busy_udata);

        /* clear busy handler */
        sqlite3_busy_handler(self, NULL, NULL);
    }
    else {
        if(sq_gettype(v, 2) != OT_CLOSURE)
            return sq_throwerror(v, _SC("invalid fisrt parameter expected closure"));

        sq_getstackobj(v, 2, &sdb->busy_cb);
        sq_addref(v, &sdb->busy_cb);
        if(_top_ > 2){
            sq_getstackobj(v, 3, &sdb->busy_udata);
            sq_addref(v, &sdb->busy_udata);
        }

        /* set busy callback */
        sqlite3_busy_handler(self, db_busy_callback, sdb);
    }

    return 0;
}

static SQRESULT sq_sqlite3_busy_timeout(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
	SQ_GET_INTEGER(v, 2, timeout);

    sqlite3_busy_timeout(self, timeout);

    /* if there was a timeout callback registered, it is now
    ** invalid/useless. free any references we may have */
    sq_release(v, &sdb->busy_cb);
    sq_resetobject(&sdb->busy_cb);
    sq_release(v, &sdb->busy_udata);
    sq_resetobject(&sdb->busy_udata);

    return 0;
}

static SQRESULT sq_sqlite3_interrupt(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_INSTANCE();
    sqlite3_interrupt(self);
    return 0;
}

/*
** =======================================================
** User Defined Functions - Context Methods
** =======================================================
*/
typedef struct {
    sqlite3_context *ctx;
    HSQOBJECT udata;
} sq_sqlite3_context_st;

static const SQChar sq_sqlite3_context_TAG[]  = _SC(":sqlite3:ctx");

static SQRESULT sq_sqlite3_context_releasehook(SQUserPointer p, SQInteger size, HSQUIRRELVM v)
{
	sq_sqlite3_context_st *ctx = ((sq_sqlite3_context_st *)p);
    /* 'free' all references */
	sq_free(ctx, sizeof(sq_sqlite3_context_st));
	return 0;
}

static SQRESULT sq_sqlite3_context_constructor(HSQUIRRELVM v) {
    sq_sqlite3_context_st *ctx = (sq_sqlite3_context_st*)sq_malloc(sizeof(sq_sqlite3_context_st));
    ctx->ctx = NULL;
    sq_resetobject(&ctx->udata);
    sq_setinstanceup(v, 1, ctx);
    sq_setreleasehook(v,1, sq_sqlite3_context_releasehook);
    return 1;
}

#define SQ_SQLITE3_GETCONTEXT(v, idx) \
    sq_sqlite3_context_st *self;\
    if((_rc_ = sq_getinstanceup(v, idx, (void**)&self, (void*)sq_sqlite3_context_TAG)) < 0) return _rc_;

#define GET_sqlite3_context_INSTANCE() SQ_SQLITE3_GETCONTEXT(v,1)

static SQRESULT sq_sqlite3_context__tostring(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_context_INSTANCE();
    char buff[64];
    snprintf(buff, sizeof(buff), "sqlite function context (%p)", self);
    sq_pushstring(v, buff, -1);
    return 1;
}

static SQRESULT sq_sqlite3_context_check_aggregate(HSQUIRRELVM v, sq_sqlite3_context_st *ctx) {
    sq_sqlite3_sdb_func *func = (sq_sqlite3_sdb_func*)sqlite3_user_data(ctx->ctx);
    if (sq_isclosure(func->fn_finalize)) {
        return sq_throwerror(v, "attempt to call aggregate method from scalar function");
    }
    return 1;
}

static SQRESULT sq_sqlite3_context_user_data(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_context_INSTANCE();
    sq_sqlite3_sdb_func *func = (sq_sqlite3_sdb_func*)sqlite3_user_data(self->ctx);
    sq_pushobject(v, func->udata);
    return 1;
}

static SQRESULT sq_sqlite3_context_aggregate_data(HSQUIRRELVM v) {
	SQ_FUNC_VARS(v);
	GET_sqlite3_context_INSTANCE();
    sq_sqlite3_context_check_aggregate(v, self);
    if(_top_ < 2){
        sq_pushobject(v, self->udata);
    }
    else
    {
        sq_release(v, &self->udata);
        sq_getstackobj(v, 2, &self->udata);
        sq_addref(v, &self->udata);
    }
    return 0;
}

static SQRESULT sq_sqlite3_context_aggregate_count(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_context_INSTANCE();
    sq_sqlite3_context_check_aggregate(v, self);
    sq_pushinteger(v, sqlite3_aggregate_count(self->ctx));
    return 1;
}

#if 0
void *sqlite3_get_auxdata(sqlite3_context*, int);
void sqlite3_set_auxdata(sqlite3_context*, int, void*, void (*)(void*));
#endif

static SQRESULT sq_sqlite3_context_result_blob(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_context_INSTANCE();
	SQ_GET_STRING(v, 2, blob);
    sqlite3_result_blob(self->ctx, (const void*)blob, blob_size, SQLITE_TRANSIENT);
    return 0;
}

static SQRESULT sq_sqlite3_context_result_double(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_context_INSTANCE();
	SQ_GET_FLOAT(v, 2, d);
    sqlite3_result_double(self->ctx, d);
    return 0;
}

static SQRESULT sq_sqlite3_context_result_error(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_context_INSTANCE();
	SQ_GET_STRING(v,2, err);
    sqlite3_result_error(self->ctx, err, err_size);
    return 0;
}

static SQRESULT sq_sqlite3_context_result_int(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_context_INSTANCE();
	SQ_GET_INTEGER(v, 2, i);
    sqlite3_result_int(self->ctx, i);
    return 0;
}

static SQRESULT sq_sqlite3_context_result_null(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_context_INSTANCE();
    sqlite3_result_null(self->ctx);
    return 0;
}

static SQRESULT sq_sqlite3_context_result_text(HSQUIRRELVM v) {
	SQ_FUNC_VARS_NO_TOP(v);
	GET_sqlite3_context_INSTANCE();
	SQ_GET_STRING(v, 2, text);
    sqlite3_result_text(self->ctx, text, text_size, SQLITE_TRANSIENT);
    return 0;
}

#define _DECL_FUNC(name,nparams,tycheck) {_SC(#name),  sq_sqlite3_context_##name,nparams,tycheck}
static SQRegFunction sq_sqlite3_context_methods[] =
{
	_DECL_FUNC(constructor,  1, _SC("x")),

	_DECL_FUNC(user_data,  1, _SC("x")),
	_DECL_FUNC(aggregate_data,  -1, _SC("x.")),
	_DECL_FUNC(aggregate_count,  1, _SC("x")),
	_DECL_FUNC(result_null,  1, _SC("x")),
	_DECL_FUNC(result_double,  2, _SC("xf")),
	_DECL_FUNC(result_int,  2, _SC("xi")),
	_DECL_FUNC(result_text,  2, _SC("xs")),
	_DECL_FUNC(result_blob,  2, _SC("xs")),
	_DECL_FUNC(result_error,  2, _SC("xs")),
	_DECL_FUNC(_tostring,  -1, _SC("x")),
	{0,0}
};
#undef _DECL_FUNC

/*
** callback functions used when calling registered sql functions
*/

static void sqlite3_push_value(HSQUIRRELVM v, sqlite3_value *value) {
    const char *tmp_value;
    switch (sqlite3_value_type(value)) {
        case SQLITE_TEXT:
            tmp_value = (const char*) sqlite3_value_text(value);
            if(tmp_value) sq_pushstring(v, tmp_value, sqlite3_value_bytes(value));
            else push_sqlite3_null(v);
            break;

        case SQLITE_INTEGER:
            {
                sqlite_int64 i64 = sqlite3_value_int64(value);
                SQInteger n = (SQInteger)i64;
                if (n == i64)
                    sq_pushinteger(v, n);
                else
                    sq_pushstring(v, (const char*) sqlite3_value_text(value), sqlite3_value_bytes(value));
            }
            break;

        case SQLITE_FLOAT:
            sq_pushfloat(v, sqlite3_value_double(value));
            break;

        case SQLITE_BLOB:
            tmp_value = (const char*) sqlite3_value_blob(value);
            if(tmp_value) sq_pushstring(v, tmp_value, sqlite3_value_bytes(value));
            else push_sqlite3_null(v);
            break;

        case SQLITE_NULL:
            push_sqlite3_null(v);
            break;

        default:
            /* things done properly (SQLite + Lua SQLite)
            ** this should never happen */
            push_sqlite3_null(v);
            break;
    }
}
//#if 0

static SQRESULT new_context_instance(HSQUIRRELVM v, sq_sqlite3_context_st **ctx){
    sq_pushregistrytable(v);
    sq_pushstring(v,_SC("sqite3_context"),-1);
    int rc = sq_rawget(v, -2);
    sq_remove(v, -2); //remove registrytable
    sq_pushroottable(v);
    rc = sq_call(v, 1, SQTrue, SQFalse);
    sq_remove(v, -2); //class
    rc = sq_getinstanceup(v, -1, (void**)ctx, (void*)sq_sqlite3_context_TAG);
    return rc;
}
/* scalar function to be called
** callback params: context, values... */
static void db_sql_normal_function(sqlite3_context *context, int argc, sqlite3_value **argv) {
    sq_sqlite3_sdb_func *func = (sq_sqlite3_sdb_func*)sqlite3_user_data(context);
    HSQUIRRELVM v = func->sdb->v;

    int n, rc;
    sq_sqlite3_context_st *ctx;
    int top = sq_gettop(v);

    /* ensure there is enough space in the stack */
    sq_reservestack(v, argc + 5);

    sq_pushobject(v, func->fn_step);
    sq_pushroottable(v);

    if (!sq_isclosure(func->fn_finalize)) {
        new_context_instance(v, &ctx);
    }
    else {
        /* reuse context userdata value */
        void *p = sqlite3_aggregate_context(context, 1);
        /* i think it is OK to use assume that using a light user data
        ** as an entry on LUA REGISTRY table will be unique */
        sq_pushregistrytable(v);
        sq_pushuserpointer(v, p);
        /* context table */
        if(sq_rawget(v, -2) != SQ_OK){
            /* not yet created? */
            sq_poptop(v); //remove null
            new_context_instance(v, &ctx);
            sq_pushuserpointer(v, p);
            sq_push(v, -2);
            sq_rawset(v, -4); //insert into registrytable
        }
        sq_remove(v, -2); //remove registrytable
    }

    /* push params */
    for (n = 0; n < argc; ++n) {
        sqlite3_push_value(v, argv[n]);
    }

    /* set context */
    ctx->ctx = context;

    if (sq_call(v, argc + 2, SQFalse, SQFalse) != SQ_OK) { //2 = roottable + ctx
        sqlite3_result_error(context, sq_getlasterror_str(v), -1);
    }

    /* invalidate context */
    ctx->ctx = NULL;

    if (!sq_isclosure(func->fn_finalize)) {
        sq_release(v, &ctx->udata);
        sq_resetobject(&ctx->udata);
    }

    sq_settop(v, top);
}

static void db_sql_finalize_function(sqlite3_context *context) {
    sq_sqlite3_sdb_func *func = (sq_sqlite3_sdb_func*)sqlite3_user_data(context);
    HSQUIRRELVM v = func->sdb->v;
    void *p = sqlite3_aggregate_context(context, 1); /* minimal mem usage */
    sq_sqlite3_context_st *ctx;
    int top = sq_gettop(v);

    sq_pushobject(v, func->fn_finalize);
    sq_pushroottable(v);

    /* i think it is OK to use assume that using a light user data
    ** as an entry on LUA REGISTRY table will be unique */
    sq_pushregistrytable(v);
    sq_pushuserpointer(v, p);
    /* remove it from registry but we'll use it last time here */
    /* context table */
    if(sq_deleteslot(v, -2, SQTrue) != SQ_OK){
        /* not yet created? - shouldn't happen in finalize function */
        sq_pop(v, 1);
        new_context_instance(v, &ctx);
        sq_pushuserpointer(v, p);
        sq_push(v, -2);
        sq_rawset(v, -4);
    }
    sq_remove(v, -2); //registrytable

    /* set context */
    ctx->ctx = context;

    if (sq_call(v, 1, SQFalse, SQFalse) != SQ_OK) {
        sqlite3_result_error(context, sq_getlasterror_str(v), -1);
    }

    /* invalidate context */
    ctx->ctx = NULL;

    /* cleanup context */
    sq_release(v, &ctx->udata);
    sq_resetobject(&ctx->udata);
    sq_settop(v, top);
}

/*
** Register a normal function
** Params: db, function name, number arguments, [ callback | step, finalize], user data
** Returns: true on sucess
**
** Normal function:
** Params: context, params
**
** Aggregate function:
** Params of step: context, params
** Params of finalize: context
*/
static SQRESULT db_register_function(HSQUIRRELVM v, int aggregate) {
	SQ_FUNC_VARS(v);
	GET_sqlite3_INSTANCE();
    SQ_GET_STRING(v, 2, name);
    SQ_GET_INTEGER(v, 3, nargs);
    if(sq_gettype(v, 4) != OT_CLOSURE)
        return sq_throwerror(v, "invalid parameter 3 expected closure");
    if (aggregate) {
        if(sq_gettype(v,5) != OT_CLOSURE)
            return sq_throwerror(v, "invalid parameter 4 expected closure");
    }

    sq_sqlite3_sdb_func *func;
    /* maybe an alternative way to allocate memory should be used/avoided */
    func = (sq_sqlite3_sdb_func*)sq_malloc(sizeof(sq_sqlite3_sdb_func));
    memset(func, 0, sizeof(sq_sqlite3_sdb_func));
    _rc_ = sqlite3_create_function(
        self, name, nargs, SQLITE_UTF8, func,
        aggregate ? NULL : db_sql_normal_function,
        aggregate ? db_sql_normal_function : NULL,
        aggregate ? db_sql_finalize_function : NULL
    );

    if (_rc_ == SQLITE_OK) {
        /* save registered function in db function list */
        func->sdb = sdb;
        func->next = sdb->func;
        sdb->func = func;

        /* save the setp/normal function callback */
        sq_resetobject(&func->fn_step);
        sq_getstackobj(v, 4, &func->fn_step);
        sq_addref(v, &func->fn_step);
        /* save the finalize function callback */
        sq_resetobject(&func->fn_finalize);
        if (aggregate) {
            sq_getstackobj(v, 5, &func->fn_finalize);
            sq_addref(v, &func->fn_finalize);
        }

        /* save user data */
        sq_resetobject(&func->udata);
        int udata_idx = aggregate ? 6 : 5;
        if(_top_ >= udata_idx){
            sq_getstackobj(v, udata_idx, &func->udata);
            sq_addref(v, &func->udata);
        }
    }
    else {
        /* free allocated memory */
        sq_free(func, sizeof(sq_sqlite3_sdb_func));
    }

    sq_pushbool(v, _rc_ == SQLITE_OK ? 1 : 0);
    return 1;
}
//#endif

static SQRESULT sq_sqlite3_create_function(HSQUIRRELVM v) {
    return db_register_function(v, 0);
}

static SQRESULT sq_sqlite3_create_aggregate(HSQUIRRELVM v) {
    return db_register_function(v, 1);
}

#define _DECL_FUNC(name,nparams,tycheck) {_SC(#name),  sq_sqlite3_##name,nparams,tycheck}
static SQRegFunction sq_sqlite3_methods[] =
{
	_DECL_FUNC(constructor,  2, _SC("xsi")),
	_DECL_FUNC(close,  1, _SC("x")),

	_DECL_FUNC(IsAutoCommitOn,  1, _SC("x")),
	_DECL_FUNC(close,  1, _SC("x")),
	_DECL_FUNC(version,  1, _SC("x")),
	_DECL_FUNC(errcode,  1, _SC("x")),
	_DECL_FUNC(errmsg,  1, _SC("x")),
	_DECL_FUNC(sleep,  1, _SC("x")),
	_DECL_FUNC(interrupt,  1, _SC("x")),
	_DECL_FUNC(progress_handler,  -2, _SC("x i|o c .")),
	_DECL_FUNC(trace,  -2, _SC("x c|o .")),
	_DECL_FUNC(busy_handler,  -2, _SC("x c|o .")),
	_DECL_FUNC(busy_timeout,  2, _SC("xi")),
	_DECL_FUNC(create_function,  4, _SC("xsic")),
	_DECL_FUNC(create_aggregate,  5, _SC("xsicc")),
	_DECL_FUNC(temp_directory,  -2, _SC("xs")),
	_DECL_FUNC(enable_shared_cache,  2, _SC("xb")),
	_DECL_FUNC(changes,  1, _SC("x")),
	_DECL_FUNC(exec,  -2, _SC("xs")),
	_DECL_FUNC(exec_dml,  -2, _SC("xs")),
	_DECL_FUNC(exec_get_first_row,  -2, _SC("xs")),
	_DECL_FUNC(exec_get_one,  -2, _SC("xs")),
	_DECL_FUNC(get_db_name,  1, _SC("x")),
	_DECL_FUNC(last_row_id,  1, _SC("x")),
	_DECL_FUNC(prepare,  -2, _SC("xs")),
	_DECL_FUNC(set_busy_timeout,  -1, _SC("xi")),
	_DECL_FUNC(total_changes,  1, _SC("x")),
#ifdef SQLITE_HAS_CODEC
	_DECL_FUNC(key,  2, _SC("xs")),
	_DECL_FUNC(rekey,  2, _SC("xs")),
#endif
	{0,0}
};

#undef _DECL_FUNC

#define INT_CONST(v,num) 	sq_pushstring(v,_SC(#num),-1);sq_pushinteger(v,num);sq_newslot(v,-3,SQTrue);



#ifdef __cplusplus
extern "C" {
#endif

    SQRESULT sqstd_register_SQLite3(HSQUIRRELVM v)
    {
        HSQOBJECT sqlite3_NULL;
        sq_pushregistrytable(v);
        sq_pushstring(v, sqlite3_NULL_Name,-1);
        sq_newuserdata(v, sizeof(void*));
        sq_resetobject(&sqlite3_NULL);
        sq_getstackobj(v, -1, &sqlite3_NULL);
        sq_newtable(v);
        sq_insert_reg_funcs(v, sqlite3_NULL_methods);
        sq_setdelegate(v, -2);
        sq_newslot(v,-3,SQTrue);

        sq_pushstring(v,_SC("sqite3_context"),-1);
        sq_newclass(v,SQFalse);
        sq_settypetag(v,-1,(void*)sq_sqlite3_context_TAG);
        sq_insert_reg_funcs(v, sq_sqlite3_context_methods);
        sq_newslot(v,-3,SQTrue);

        sq_poptop(v); //remove registrytable

        sq_pushstring(v,SQLite3_TAG,-1);
        sq_newclass(v,SQFalse);
        sq_settypetag(v,-1,(void*)SQLite3_TAG);
        sq_insert_reg_funcs(v, sq_sqlite3_methods);

        INT_CONST(v,SQLITE_OPEN_CREATE);
        INT_CONST(v,SQLITE_OPEN_READWRITE);
        INT_CONST(v,SQLITE_OPEN_SHAREDCACHE);
        INT_CONST(v,SQLITE_OPEN_SUBLATIN_NA_LIKE);

        INT_CONST(v,SQLITE_OK);
        INT_CONST(v,SQLITE_INTERRUPT);

        //push sqlite3_NULL as a member
        sq_pushstring(v, nullName,-1);
        sq_pushobject(v, sqlite3_NULL);
        sq_newslot(v,-3,SQTrue);

        sq_newslot(v,-3,SQTrue);

        sq_pushstring(v, SQLite3_Stmt_TAG,-1);
        sq_newclass(v,SQFalse);
        sq_settypetag(v,-1,(void*)SQLite3_Stmt_TAG);
        sq_insert_reg_funcs(v, sq_sqlite3_stmt_methods);

        INT_CONST(v,SQLITE_OK);
        INT_CONST(v,SQLITE_ROW);
        INT_CONST(v,SQLITE_DONE);
        INT_CONST(v,AS_STRING_ALWAYS);
        INT_CONST(v,NULL_AS_EMPTY_STR);

        //push sqlite3_NULL as a member
        sq_pushstring(v, nullName,-1);
        sq_pushobject(v, sqlite3_NULL);
        sq_newslot(v,-3,SQTrue);

        sq_newslot(v,-3,SQTrue);
        return 1;
    }

#ifdef __cplusplus
}
#endif