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path: root/vendor/github.com/go-sql-driver/mysql/buffer.go
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Diffstat (limited to 'vendor/github.com/go-sql-driver/mysql/buffer.go')
-rw-r--r--vendor/github.com/go-sql-driver/mysql/buffer.go160
1 files changed, 0 insertions, 160 deletions
diff --git a/vendor/github.com/go-sql-driver/mysql/buffer.go b/vendor/github.com/go-sql-driver/mysql/buffer.go
deleted file mode 100644
index 19486bd6..00000000
--- a/vendor/github.com/go-sql-driver/mysql/buffer.go
+++ /dev/null
@@ -1,160 +0,0 @@
-// Go MySQL Driver - A MySQL-Driver for Go's database/sql package
-//
-// Copyright 2013 The Go-MySQL-Driver Authors. All rights reserved.
-//
-// This Source Code Form is subject to the terms of the Mozilla Public
-// License, v. 2.0. If a copy of the MPL was not distributed with this file,
-// You can obtain one at http://mozilla.org/MPL/2.0/.
-
-package mysql
-
-import (
- "io"
- "net"
- "time"
-)
-
-const defaultBufSize = 4096
-
-// A buffer which is used for both reading and writing.
-// This is possible since communication on each connection is synchronous.
-// In other words, we can't write and read simultaneously on the same connection.
-// The buffer is similar to bufio.Reader / Writer but zero-copy-ish
-// Also highly optimized for this particular use case.
-type buffer struct {
- buf []byte // buf is a byte buffer who's length and capacity are equal.
- nc net.Conn
- idx int
- length int
- timeout time.Duration
-}
-
-// newBuffer allocates and returns a new buffer.
-func newBuffer(nc net.Conn) buffer {
- return buffer{
- buf: make([]byte, defaultBufSize),
- nc: nc,
- }
-}
-
-// fill reads into the buffer until at least _need_ bytes are in it
-func (b *buffer) fill(need int) error {
- n := b.length
-
- // move existing data to the beginning
- if n > 0 && b.idx > 0 {
- copy(b.buf[0:n], b.buf[b.idx:])
- }
-
- // grow buffer if necessary
- // TODO: let the buffer shrink again at some point
- // Maybe keep the org buf slice and swap back?
- if need > len(b.buf) {
- // Round up to the next multiple of the default size
- newBuf := make([]byte, ((need/defaultBufSize)+1)*defaultBufSize)
- copy(newBuf, b.buf)
- b.buf = newBuf
- }
-
- b.idx = 0
-
- for {
- if b.timeout > 0 {
- if err := b.nc.SetReadDeadline(time.Now().Add(b.timeout)); err != nil {
- return err
- }
- }
-
- nn, err := b.nc.Read(b.buf[n:])
- n += nn
-
- switch err {
- case nil:
- if n < need {
- continue
- }
- b.length = n
- return nil
-
- case io.EOF:
- if n >= need {
- b.length = n
- return nil
- }
- return io.ErrUnexpectedEOF
-
- default:
- return err
- }
- }
-}
-
-// returns next N bytes from buffer.
-// The returned slice is only guaranteed to be valid until the next read
-func (b *buffer) readNext(need int) ([]byte, error) {
- if b.length < need {
- // refill
- if err := b.fill(need); err != nil {
- return nil, err
- }
- }
-
- offset := b.idx
- b.idx += need
- b.length -= need
- return b.buf[offset:b.idx], nil
-}
-
-// takeBuffer returns a buffer with the requested size.
-// If possible, a slice from the existing buffer is returned.
-// Otherwise a bigger buffer is made.
-// Only one buffer (total) can be used at a time.
-func (b *buffer) takeBuffer(length int) ([]byte, error) {
- if b.length > 0 {
- return nil, ErrBusyBuffer
- }
-
- // test (cheap) general case first
- if length <= cap(b.buf) {
- return b.buf[:length], nil
- }
-
- if length < maxPacketSize {
- b.buf = make([]byte, length)
- return b.buf, nil
- }
-
- // buffer is larger than we want to store.
- return make([]byte, length), nil
-}
-
-// takeSmallBuffer is shortcut which can be used if length is
-// known to be smaller than defaultBufSize.
-// Only one buffer (total) can be used at a time.
-func (b *buffer) takeSmallBuffer(length int) ([]byte, error) {
- if b.length > 0 {
- return nil, ErrBusyBuffer
- }
- return b.buf[:length], nil
-}
-
-// takeCompleteBuffer returns the complete existing buffer.
-// This can be used if the necessary buffer size is unknown.
-// cap and len of the returned buffer will be equal.
-// Only one buffer (total) can be used at a time.
-func (b *buffer) takeCompleteBuffer() ([]byte, error) {
- if b.length > 0 {
- return nil, ErrBusyBuffer
- }
- return b.buf, nil
-}
-
-// store stores buf, an updated buffer, if its suitable to do so.
-func (b *buffer) store(buf []byte) error {
- if b.length > 0 {
- return ErrBusyBuffer
- } else if cap(buf) <= maxPacketSize && cap(buf) > cap(b.buf) {
- b.buf = buf[:cap(buf)]
- }
- return nil
-}