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-rw-r--r--vendor/golang.org/x/net/http2/fixed_buffer.go60
1 files changed, 60 insertions, 0 deletions
diff --git a/vendor/golang.org/x/net/http2/fixed_buffer.go b/vendor/golang.org/x/net/http2/fixed_buffer.go
new file mode 100644
index 0000000..47da0f0
--- /dev/null
+++ b/vendor/golang.org/x/net/http2/fixed_buffer.go
@@ -0,0 +1,60 @@
+// Copyright 2014 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 http2
+
+import (
+ "errors"
+)
+
+// fixedBuffer is an io.ReadWriter backed by a fixed size buffer.
+// It never allocates, but moves old data as new data is written.
+type fixedBuffer struct {
+ buf []byte
+ r, w int
+}
+
+var (
+ errReadEmpty = errors.New("read from empty fixedBuffer")
+ errWriteFull = errors.New("write on full fixedBuffer")
+)
+
+// Read copies bytes from the buffer into p.
+// It is an error to read when no data is available.
+func (b *fixedBuffer) Read(p []byte) (n int, err error) {
+ if b.r == b.w {
+ return 0, errReadEmpty
+ }
+ n = copy(p, b.buf[b.r:b.w])
+ b.r += n
+ if b.r == b.w {
+ b.r = 0
+ b.w = 0
+ }
+ return n, nil
+}
+
+// Len returns the number of bytes of the unread portion of the buffer.
+func (b *fixedBuffer) Len() int {
+ return b.w - b.r
+}
+
+// Write copies bytes from p into the buffer.
+// It is an error to write more data than the buffer can hold.
+func (b *fixedBuffer) Write(p []byte) (n int, err error) {
+ // Slide existing data to beginning.
+ if b.r > 0 && len(p) > len(b.buf)-b.w {
+ copy(b.buf, b.buf[b.r:b.w])
+ b.w -= b.r
+ b.r = 0
+ }
+
+ // Write new data.
+ n = copy(b.buf[b.w:], p)
+ b.w += n
+ if n < len(p) {
+ err = errWriteFull
+ }
+ return n, err
+}