diff options
Diffstat (limited to '')
-rw-r--r-- | dependencies/pkg/mod/github.com/lib/pq@v1.10.7/copy.go | 341 |
1 files changed, 341 insertions, 0 deletions
diff --git a/dependencies/pkg/mod/github.com/lib/pq@v1.10.7/copy.go b/dependencies/pkg/mod/github.com/lib/pq@v1.10.7/copy.go new file mode 100644 index 0000000..2f5c1ec --- /dev/null +++ b/dependencies/pkg/mod/github.com/lib/pq@v1.10.7/copy.go @@ -0,0 +1,341 @@ +package pq + +import ( + "context" + "database/sql/driver" + "encoding/binary" + "errors" + "fmt" + "sync" +) + +var ( + errCopyInClosed = errors.New("pq: copyin statement has already been closed") + errBinaryCopyNotSupported = errors.New("pq: only text format supported for COPY") + errCopyToNotSupported = errors.New("pq: COPY TO is not supported") + errCopyNotSupportedOutsideTxn = errors.New("pq: COPY is only allowed inside a transaction") + errCopyInProgress = errors.New("pq: COPY in progress") +) + +// CopyIn creates a COPY FROM statement which can be prepared with +// Tx.Prepare(). The target table should be visible in search_path. +func CopyIn(table string, columns ...string) string { + stmt := "COPY " + QuoteIdentifier(table) + " (" + for i, col := range columns { + if i != 0 { + stmt += ", " + } + stmt += QuoteIdentifier(col) + } + stmt += ") FROM STDIN" + return stmt +} + +// CopyInSchema creates a COPY FROM statement which can be prepared with +// Tx.Prepare(). +func CopyInSchema(schema, table string, columns ...string) string { + stmt := "COPY " + QuoteIdentifier(schema) + "." + QuoteIdentifier(table) + " (" + for i, col := range columns { + if i != 0 { + stmt += ", " + } + stmt += QuoteIdentifier(col) + } + stmt += ") FROM STDIN" + return stmt +} + +type copyin struct { + cn *conn + buffer []byte + rowData chan []byte + done chan bool + + closed bool + + mu struct { + sync.Mutex + err error + driver.Result + } +} + +const ciBufferSize = 64 * 1024 + +// flush buffer before the buffer is filled up and needs reallocation +const ciBufferFlushSize = 63 * 1024 + +func (cn *conn) prepareCopyIn(q string) (_ driver.Stmt, err error) { + if !cn.isInTransaction() { + return nil, errCopyNotSupportedOutsideTxn + } + + ci := ©in{ + cn: cn, + buffer: make([]byte, 0, ciBufferSize), + rowData: make(chan []byte), + done: make(chan bool, 1), + } + // add CopyData identifier + 4 bytes for message length + ci.buffer = append(ci.buffer, 'd', 0, 0, 0, 0) + + b := cn.writeBuf('Q') + b.string(q) + cn.send(b) + +awaitCopyInResponse: + for { + t, r := cn.recv1() + switch t { + case 'G': + if r.byte() != 0 { + err = errBinaryCopyNotSupported + break awaitCopyInResponse + } + go ci.resploop() + return ci, nil + case 'H': + err = errCopyToNotSupported + break awaitCopyInResponse + case 'E': + err = parseError(r) + case 'Z': + if err == nil { + ci.setBad(driver.ErrBadConn) + errorf("unexpected ReadyForQuery in response to COPY") + } + cn.processReadyForQuery(r) + return nil, err + default: + ci.setBad(driver.ErrBadConn) + errorf("unknown response for copy query: %q", t) + } + } + + // something went wrong, abort COPY before we return + b = cn.writeBuf('f') + b.string(err.Error()) + cn.send(b) + + for { + t, r := cn.recv1() + switch t { + case 'c', 'C', 'E': + case 'Z': + // correctly aborted, we're done + cn.processReadyForQuery(r) + return nil, err + default: + ci.setBad(driver.ErrBadConn) + errorf("unknown response for CopyFail: %q", t) + } + } +} + +func (ci *copyin) flush(buf []byte) { + // set message length (without message identifier) + binary.BigEndian.PutUint32(buf[1:], uint32(len(buf)-1)) + + _, err := ci.cn.c.Write(buf) + if err != nil { + panic(err) + } +} + +func (ci *copyin) resploop() { + for { + var r readBuf + t, err := ci.cn.recvMessage(&r) + if err != nil { + ci.setBad(driver.ErrBadConn) + ci.setError(err) + ci.done <- true + return + } + switch t { + case 'C': + // complete + res, _ := ci.cn.parseComplete(r.string()) + ci.setResult(res) + case 'N': + if n := ci.cn.noticeHandler; n != nil { + n(parseError(&r)) + } + case 'Z': + ci.cn.processReadyForQuery(&r) + ci.done <- true + return + case 'E': + err := parseError(&r) + ci.setError(err) + default: + ci.setBad(driver.ErrBadConn) + ci.setError(fmt.Errorf("unknown response during CopyIn: %q", t)) + ci.done <- true + return + } + } +} + +func (ci *copyin) setBad(err error) { + ci.cn.err.set(err) +} + +func (ci *copyin) getBad() error { + return ci.cn.err.get() +} + +func (ci *copyin) err() error { + ci.mu.Lock() + err := ci.mu.err + ci.mu.Unlock() + return err +} + +// setError() sets ci.err if one has not been set already. Caller must not be +// holding ci.Mutex. +func (ci *copyin) setError(err error) { + ci.mu.Lock() + if ci.mu.err == nil { + ci.mu.err = err + } + ci.mu.Unlock() +} + +func (ci *copyin) setResult(result driver.Result) { + ci.mu.Lock() + ci.mu.Result = result + ci.mu.Unlock() +} + +func (ci *copyin) getResult() driver.Result { + ci.mu.Lock() + result := ci.mu.Result + ci.mu.Unlock() + if result == nil { + return driver.RowsAffected(0) + } + return result +} + +func (ci *copyin) NumInput() int { + return -1 +} + +func (ci *copyin) Query(v []driver.Value) (r driver.Rows, err error) { + return nil, ErrNotSupported +} + +// Exec inserts values into the COPY stream. The insert is asynchronous +// and Exec can return errors from previous Exec calls to the same +// COPY stmt. +// +// You need to call Exec(nil) to sync the COPY stream and to get any +// errors from pending data, since Stmt.Close() doesn't return errors +// to the user. +func (ci *copyin) Exec(v []driver.Value) (r driver.Result, err error) { + if ci.closed { + return nil, errCopyInClosed + } + + if err := ci.getBad(); err != nil { + return nil, err + } + defer ci.cn.errRecover(&err) + + if err := ci.err(); err != nil { + return nil, err + } + + if len(v) == 0 { + if err := ci.Close(); err != nil { + return driver.RowsAffected(0), err + } + + return ci.getResult(), nil + } + + numValues := len(v) + for i, value := range v { + ci.buffer = appendEncodedText(&ci.cn.parameterStatus, ci.buffer, value) + if i < numValues-1 { + ci.buffer = append(ci.buffer, '\t') + } + } + + ci.buffer = append(ci.buffer, '\n') + + if len(ci.buffer) > ciBufferFlushSize { + ci.flush(ci.buffer) + // reset buffer, keep bytes for message identifier and length + ci.buffer = ci.buffer[:5] + } + + return driver.RowsAffected(0), nil +} + +// CopyData inserts a raw string into the COPY stream. The insert is +// asynchronous and CopyData can return errors from previous CopyData calls to +// the same COPY stmt. +// +// You need to call Exec(nil) to sync the COPY stream and to get any +// errors from pending data, since Stmt.Close() doesn't return errors +// to the user. +func (ci *copyin) CopyData(ctx context.Context, line string) (r driver.Result, err error) { + if ci.closed { + return nil, errCopyInClosed + } + + if finish := ci.cn.watchCancel(ctx); finish != nil { + defer finish() + } + + if err := ci.getBad(); err != nil { + return nil, err + } + defer ci.cn.errRecover(&err) + + if err := ci.err(); err != nil { + return nil, err + } + + ci.buffer = append(ci.buffer, []byte(line)...) + ci.buffer = append(ci.buffer, '\n') + + if len(ci.buffer) > ciBufferFlushSize { + ci.flush(ci.buffer) + // reset buffer, keep bytes for message identifier and length + ci.buffer = ci.buffer[:5] + } + + return driver.RowsAffected(0), nil +} + +func (ci *copyin) Close() (err error) { + if ci.closed { // Don't do anything, we're already closed + return nil + } + ci.closed = true + + if err := ci.getBad(); err != nil { + return err + } + defer ci.cn.errRecover(&err) + + if len(ci.buffer) > 0 { + ci.flush(ci.buffer) + } + // Avoid touching the scratch buffer as resploop could be using it. + err = ci.cn.sendSimpleMessage('c') + if err != nil { + return err + } + + <-ci.done + ci.cn.inCopy = false + + if err := ci.err(); err != nil { + return err + } + return nil +} |