Add comments.

systemlib
mattn 2013-01-31 16:48:30 +09:00
parent ae4b60773a
commit 6e13c4512d
1 changed files with 44 additions and 18 deletions

View File

@ -58,17 +58,42 @@ func init() {
sql.Register("sqlite3", &SQLiteDriver{})
}
// Driver struct.
type SQLiteDriver struct {
}
// Conn struct.
type SQLiteConn struct {
db *C.sqlite3
}
// Tx struct.
type SQLiteTx struct {
c *SQLiteConn
}
// Stmt struct.
type SQLiteStmt struct {
c *SQLiteConn
s *C.sqlite3_stmt
t string
closed bool
}
// Result struct.
type SQLiteResult struct {
s *SQLiteStmt
}
// Rows struct.
type SQLiteRows struct {
s *SQLiteStmt
nc int
cols []string
decltype []string
}
// Commit transaction.
func (tx *SQLiteTx) Commit() error {
if err := tx.c.exec("COMMIT"); err != nil {
return err
@ -76,6 +101,7 @@ func (tx *SQLiteTx) Commit() error {
return nil
}
// Rollback transaction.
func (tx *SQLiteTx) Rollback() error {
if err := tx.c.exec("ROLLBACK"); err != nil {
return err
@ -93,6 +119,7 @@ func (c *SQLiteConn) exec(cmd string) error {
return nil
}
// Begin transaction.
func (c *SQLiteConn) Begin() (driver.Tx, error) {
if err := c.exec("BEGIN"); err != nil {
return nil, err
@ -100,6 +127,12 @@ func (c *SQLiteConn) Begin() (driver.Tx, error) {
return &SQLiteTx{c}, nil
}
// Open database and return a new connection.
// You can specify DSN string with URI filename.
// test.db
// file:test.db?cache=shared&mode=memory
// :memory:
// file::memory:
func (d *SQLiteDriver) Open(dsn string) (driver.Conn, error) {
if C.sqlite3_threadsafe() == 0 {
return nil, errors.New("sqlite library was not compiled for thread-safe operation")
@ -129,6 +162,7 @@ func (d *SQLiteDriver) Open(dsn string) (driver.Conn, error) {
return &SQLiteConn{db}, nil
}
// Close the connection.
func (c *SQLiteConn) Close() error {
s := C.sqlite3_next_stmt(c.db, nil)
for s != nil {
@ -143,13 +177,7 @@ func (c *SQLiteConn) Close() error {
return nil
}
type SQLiteStmt struct {
c *SQLiteConn
s *C.sqlite3_stmt
t string
closed bool
}
// Prepare query string. Return a new statement.
func (c *SQLiteConn) Prepare(query string) (driver.Stmt, error) {
pquery := C.CString(query)
defer C.free(unsafe.Pointer(pquery))
@ -166,6 +194,7 @@ func (c *SQLiteConn) Prepare(query string) (driver.Stmt, error) {
return &SQLiteStmt{c: c, s: s, t: t}, nil
}
// Close the statement.
func (s *SQLiteStmt) Close() error {
if s.closed {
return nil
@ -178,6 +207,7 @@ func (s *SQLiteStmt) Close() error {
return nil
}
// Return a number of parameters.
func (s *SQLiteStmt) NumInput() int {
return int(C.sqlite3_bind_parameter_count(s.s))
}
@ -234,6 +264,7 @@ func (s *SQLiteStmt) bind(args []driver.Value) error {
return nil
}
// Query the statment with arguments. Return records.
func (s *SQLiteStmt) Query(args []driver.Value) (driver.Rows, error) {
if err := s.bind(args); err != nil {
return nil, err
@ -241,18 +272,17 @@ func (s *SQLiteStmt) Query(args []driver.Value) (driver.Rows, error) {
return &SQLiteRows{s, int(C.sqlite3_column_count(s.s)), nil, nil}, nil
}
type SQLiteResult struct {
s *SQLiteStmt
}
// Return last inserted ID.
func (r *SQLiteResult) LastInsertId() (int64, error) {
return int64(C._sqlite3_last_insert_rowid(r.s.c.db)), nil
}
// Return how many rows affected.
func (r *SQLiteResult) RowsAffected() (int64, error) {
return int64(C._sqlite3_changes(r.s.c.db)), nil
}
// Execute the statement with arguments. Return result object.
func (s *SQLiteStmt) Exec(args []driver.Value) (driver.Result, error) {
if err := s.bind(args); err != nil {
return nil, err
@ -264,13 +294,7 @@ func (s *SQLiteStmt) Exec(args []driver.Value) (driver.Result, error) {
return &SQLiteResult{s}, nil
}
type SQLiteRows struct {
s *SQLiteStmt
nc int
cols []string
decltype []string
}
// Close the rows.
func (rc *SQLiteRows) Close() error {
rv := C.sqlite3_reset(rc.s.s)
if rv != C.SQLITE_OK {
@ -279,6 +303,7 @@ func (rc *SQLiteRows) Close() error {
return nil
}
// Return column names.
func (rc *SQLiteRows) Columns() []string {
if rc.nc != len(rc.cols) {
rc.cols = make([]string, rc.nc)
@ -289,6 +314,7 @@ func (rc *SQLiteRows) Columns() []string {
return rc.cols
}
// Move cursor to next.
func (rc *SQLiteRows) Next(dest []driver.Value) error {
rv := C.sqlite3_step(rc.s.s)
if rv == C.SQLITE_DONE {