// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package sqlite provides access to the SQLite library, version 3.
package sqlite
/*
#cgo LDFLAGS: -lsqlite3
#include <sqlite3.h>
#include <stdlib.h>
// These wrappers are necessary because SQLITE_TRANSIENT
// is a pointer constant, and cgo doesn't translate them correctly.
// The definition in sqlite3.h is:
//
// typedef void (*sqlite3_destructor_type)(void*);
// #define SQLITE_STATIC ((sqlite3_destructor_type)0)
// #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)
static int my_bind_text(sqlite3_stmt *stmt, int n, char *p, int np) {
return sqlite3_bind_text(stmt, n, p, np, SQLITE_TRANSIENT);
}
static int my_bind_blob(sqlite3_stmt *stmt, int n, void *p, int np) {
return sqlite3_bind_blob(stmt, n, p, np, SQLITE_TRANSIENT);
}
*/
import "C"
import (
"errors"
"fmt"
"reflect"
"strconv"
"time"
"unsafe"
)
type Errno int
func (e Errno) Error() string {
s := errText[e]
if s == "" {
return fmt.Sprintf("errno %d", int(e))
}
return s
}
var (
ErrError error = Errno(1) // /* SQL error or missing database */
ErrInternal error = Errno(2) // /* Internal logic error in SQLite */
ErrPerm error = Errno(3) // /* Access permission denied */
ErrAbort error = Errno(4) // /* Callback routine requested an abort */
ErrBusy error = Errno(5) // /* The database file is locked */
ErrLocked error = Errno(6) // /* A table in the database is locked */
ErrNoMem error = Errno(7) // /* A malloc() failed */
ErrReadOnly error = Errno(8) // /* Attempt to write a readonly database */
ErrInterrupt error = Errno(9) // /* Operation terminated by sqlite3_interrupt()*/
ErrIOErr error = Errno(10) // /* Some kind of disk I/O error occurred */
ErrCorrupt error = Errno(11) // /* The database disk image is malformed */
ErrFull error = Errno(13) // /* Insertion failed because database is full */
ErrCantOpen error = Errno(14) // /* Unable to open the database file */
ErrEmpty error = Errno(16) // /* Database is empty */
ErrSchema error = Errno(17) // /* The database schema changed */
ErrTooBig error = Errno(18) // /* String or BLOB exceeds size limit */
ErrConstraint error = Errno(19) // /* Abort due to constraint violation */
ErrMismatch error = Errno(20) // /* Data type mismatch */
ErrMisuse error = Errno(21) // /* Library used incorrectly */
ErrNolfs error = Errno(22) // /* Uses OS features not supported on host */
ErrAuth error = Errno(23) // /* Authorization denied */
ErrFormat error = Errno(24) // /* Auxiliary database format error */
ErrRange error = Errno(25) // /* 2nd parameter to sqlite3_bind out of range */
ErrNotDB error = Errno(26) // /* File opened that is not a database file */
Row = Errno(100) // /* sqlite3_step() has another row ready */
Done = Errno(101) // /* sqlite3_step() has finished executing */
)
var errText = map[Errno]string{
1: "SQL error or missing database",
2: "Internal logic error in SQLite",
3: "Access permission denied",
4: "Callback routine requested an abort",
5: "The database file is locked",
6: "A table in the database is locked",
7: "A malloc() failed",
8: "Attempt to write a readonly database",
9: "Operation terminated by sqlite3_interrupt()*/",
10: "Some kind of disk I/O error occurred",
11: "The database disk image is malformed",
12: "NOT USED. Table or record not found",
13: "Insertion failed because database is full",
14: "Unable to open the database file",
15: "NOT USED. Database lock protocol error",
16: "Database is empty",
17: "The database schema changed",
18: "String or BLOB exceeds size limit",
19: "Abort due to constraint violation",
20: "Data type mismatch",
21: "Library used incorrectly",
22: "Uses OS features not supported on host",
23: "Authorization denied",
24: "Auxiliary database format error",
25: "2nd parameter to sqlite3_bind out of range",
26: "File opened that is not a database file",
100: "sqlite3_step() has another row ready",
101: "sqlite3_step() has finished executing",
}
func (c *Conn) error(rv C.int) error {
if c == nil || c.db == nil {
return errors.New("nil sqlite database")
}
if rv == 0 {
return nil
}
if rv == 21 { // misuse
return Errno(rv)
}
return errors.New(Errno(rv).Error() + ": " + C.GoString(C.sqlite3_errmsg(c.db)))
}
type Conn struct {
db *C.sqlite3
}
func Version() string {
p := C.sqlite3_libversion()
return C.GoString(p)
}
func Open(filename string) (*Conn, error) {
if C.sqlite3_threadsafe() == 0 {
return nil, errors.New("sqlite library was not compiled for thread-safe operation")
}
var db *C.sqlite3
name := C.CString(filename)
defer C.free(unsafe.Pointer(name))
rv := C.sqlite3_open_v2(name, &db,
C.SQLITE_OPEN_FULLMUTEX|
C.SQLITE_OPEN_READWRITE|
C.SQLITE_OPEN_CREATE,
nil)
if rv != 0 {
return nil, Errno(rv)
}
if db == nil {
return nil, errors.New("sqlite succeeded without returning a database")
}
return &Conn{db}, nil
}
func NewBackup(dst *Conn, dstTable string, src *Conn, srcTable string) (*Backup, error) {
dname := C.CString(dstTable)
sname := C.CString(srcTable)
defer C.free(unsafe.Pointer(dname))
defer C.free(unsafe.Pointer(sname))
sb := C.sqlite3_backup_init(dst.db, dname, src.db, sname)
if sb == nil {
return nil, dst.error(C.sqlite3_errcode(dst.db))
}
return &Backup{sb, dst, src}, nil
}
type Backup struct {
sb *C.sqlite3_backup
dst, src *Conn
}
func (b *Backup) Step(npage int) error {
rv := C.sqlite3_backup_step(b.sb, C.int(npage))
if rv == 0 || Errno(rv) == ErrBusy || Errno(rv) == ErrLocked {
return nil
}
return Errno(rv)
}
type BackupStatus struct {
Remaining int
PageCount int
}
func (b *Backup) Status() BackupStatus {
return BackupStatus{int(C.sqlite3_backup_remaining(b.sb)), int(C.sqlite3_backup_pagecount(b.sb))}
}
func (b *Backup) Run(npage int, period time.Duration, c chan<- BackupStatus) error {
var err error
for {
err = b.Step(npage)
if err != nil {
break
}
if c != nil {
c <- b.Status()
}
time.Sleep(period)
}
return b.dst.error(C.sqlite3_errcode(b.dst.db))
}
func (b *Backup) Close() error {
if b.sb == nil {
return errors.New("backup already closed")
}
C.sqlite3_backup_finish(b.sb)
b.sb = nil
return nil
}
func (c *Conn) BusyTimeout(ms int) error {
rv := C.sqlite3_busy_timeout(c.db, C.int(ms))
if rv == 0 {
return nil
}
return Errno(rv)
}
func (c *Conn) Exec(cmd string, args ...interface{}) error {
s, err := c.Prepare(cmd)
if err != nil {
return err
}
defer s.Finalize()
err = s.Exec(args...)
if err != nil {
return err
}
rv := C.sqlite3_step(s.stmt)
if Errno(rv) != Done {
return c.error(rv)
}
return nil
}
type Stmt struct {
c *Conn
stmt *C.sqlite3_stmt
err error
t0 time.Time
sql string
args string
}
func (c *Conn) Prepare(cmd string) (*Stmt, error) {
if c == nil || c.db == nil {
return nil, errors.New("nil sqlite database")
}
cmdstr := C.CString(cmd)
defer C.free(unsafe.Pointer(cmdstr))
var stmt *C.sqlite3_stmt
var tail *C.char
rv := C.sqlite3_prepare_v2(c.db, cmdstr, C.int(len(cmd)+1), &stmt, &tail)
if rv != 0 {
return nil, c.error(rv)
}
return &Stmt{c: c, stmt: stmt, sql: cmd, t0: time.Now()}, nil
}
func (s *Stmt) Exec(args ...interface{}) error {
s.args = fmt.Sprintf(" %v", []interface{}(args))
rv := C.sqlite3_reset(s.stmt)
if rv != 0 {
return s.c.error(rv)
}
n := int(C.sqlite3_bind_parameter_count(s.stmt))
if n != len(args) {
return errors.New(fmt.Sprintf("incorrect argument count for Stmt.Exec: have %d want %d", len(args), n))
}
for i, v := range args {
var str string
switch v := v.(type) {
case []byte:
var p *byte
if len(v) > 0 {
p = &v[0]
}
if rv := C.my_bind_blob(s.stmt, C.int(i+1), unsafe.Pointer(p), C.int(len(v))); rv != 0 {
return s.c.error(rv)
}
continue
case bool:
if v {
str = "1"
} else {
str = "0"
}
default:
str = fmt.Sprint(v)
}
cstr := C.CString(str)
rv := C.my_bind_text(s.stmt, C.int(i+1), cstr, C.int(len(str)))
C.free(unsafe.Pointer(cstr))
if rv != 0 {
return s.c.error(rv)
}
}
return nil
}
func (s *Stmt) Error() error {
return s.err
}
func (s *Stmt) Next() bool {
rv := C.sqlite3_step(s.stmt)
err := Errno(rv)
if err == Row {
return true
}
if err != Done {
s.err = s.c.error(rv)
}
return false
}
func (s *Stmt) Reset() error {
C.sqlite3_reset(s.stmt)
return nil
}
func (s *Stmt) Scan(args ...interface{}) error {
n := int(C.sqlite3_column_count(s.stmt))
if n != len(args) {
return errors.New(fmt.Sprintf("incorrect argument count for Stmt.Scan: have %d want %d", len(args), n))
}
for i, v := range args {
n := C.sqlite3_column_bytes(s.stmt, C.int(i))
p := C.sqlite3_column_blob(s.stmt, C.int(i))
if p == nil && n > 0 {
return errors.New("got nil blob")
}
var data []byte
if n > 0 {
data = (*[1 << 30]byte)(unsafe.Pointer(p))[0:n]
}
switch v := v.(type) {
case *[]byte:
*v = data
case *string:
*v = string(data)
case *bool:
*v = string(data) == "1"
case *int:
x, err := strconv.Atoi(string(data))
if err != nil {
return errors.New("arg " + strconv.Itoa(i) + " as int: " + err.Error())
}
*v = x
case *int64:
x, err := strconv.ParseInt(string(data), 10, 64)
if err != nil {
return errors.New("arg " + strconv.Itoa(i) + " as int64: " + err.Error())
}
*v = x
case *float64:
x, err := strconv.ParseFloat(string(data), 64)
if err != nil {
return errors.New("arg " + strconv.Itoa(i) + " as float64: " + err.Error())
}
*v = x
default:
return errors.New("unsupported type in Scan: " + reflect.TypeOf(v).String())
}
}
return nil
}
func (s *Stmt) SQL() string {
return s.sql + s.args
}
func (s *Stmt) Nanoseconds() int64 {
return time.Now().Sub(s.t0).Nanoseconds()
}
func (s *Stmt) Finalize() error {
rv := C.sqlite3_finalize(s.stmt)
if rv != 0 {
return s.c.error(rv)
}
return nil
}
func (c *Conn) Close() error {
if c == nil || c.db == nil {
return errors.New("nil sqlite database")
}
rv := C.sqlite3_close(c.db)
if rv != 0 {
return c.error(rv)
}
c.db = nil
return nil
}