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-rw-r--r--dependencies/pkg/mod/golang.org/x/exp@v0.0.0-20220613132600-b0d781184e0d/mmap/mmap_other.go76
1 files changed, 76 insertions, 0 deletions
diff --git a/dependencies/pkg/mod/golang.org/x/exp@v0.0.0-20220613132600-b0d781184e0d/mmap/mmap_other.go b/dependencies/pkg/mod/golang.org/x/exp@v0.0.0-20220613132600-b0d781184e0d/mmap/mmap_other.go
new file mode 100644
index 0000000..1e7b948
--- /dev/null
+++ b/dependencies/pkg/mod/golang.org/x/exp@v0.0.0-20220613132600-b0d781184e0d/mmap/mmap_other.go
@@ -0,0 +1,76 @@
+// Copyright 2015 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.
+
+//go:build !linux && !windows && !darwin
+// +build !linux,!windows,!darwin
+
+// Package mmap provides a way to memory-map a file.
+package mmap
+
+import (
+ "fmt"
+ "os"
+)
+
+// ReaderAt reads a memory-mapped file.
+//
+// Like any io.ReaderAt, clients can execute parallel ReadAt calls, but it is
+// not safe to call Close and reading methods concurrently.
+type ReaderAt struct {
+ f *os.File
+ len int
+}
+
+// Close closes the reader.
+func (r *ReaderAt) Close() error {
+ return r.f.Close()
+}
+
+// Len returns the length of the underlying memory-mapped file.
+func (r *ReaderAt) Len() int {
+ return r.len
+}
+
+// At returns the byte at index i.
+func (r *ReaderAt) At(i int) byte {
+ if i < 0 || r.len <= i {
+ panic("index out of range")
+ }
+ var b [1]byte
+ r.ReadAt(b[:], int64(i))
+ return b[0]
+}
+
+// ReadAt implements the io.ReaderAt interface.
+func (r *ReaderAt) ReadAt(p []byte, off int64) (int, error) {
+ return r.f.ReadAt(p, off)
+}
+
+// Open memory-maps the named file for reading.
+func Open(filename string) (*ReaderAt, error) {
+ f, err := os.Open(filename)
+ if err != nil {
+ return nil, err
+ }
+ fi, err := f.Stat()
+ if err != nil {
+ f.Close()
+ return nil, err
+ }
+
+ size := fi.Size()
+ if size < 0 {
+ f.Close()
+ return nil, fmt.Errorf("mmap: file %q has negative size", filename)
+ }
+ if size != int64(int(size)) {
+ f.Close()
+ return nil, fmt.Errorf("mmap: file %q is too large", filename)
+ }
+
+ return &ReaderAt{
+ f: f,
+ len: int(fi.Size()),
+ }, nil
+}