1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
|
// Copyright 2011 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 mmap
import (
"fmt"
"os"
"syscall"
"unsafe"
"internal/syscall/windows"
)
func mmapFile(f *os.File) (Data, error) {
st, err := f.Stat()
if err != nil {
return Data{}, err
}
size := st.Size()
if size == 0 {
return Data{f, nil}, nil
}
h, err := syscall.CreateFileMapping(syscall.Handle(f.Fd()), nil, syscall.PAGE_READONLY, 0, 0, nil)
if err != nil {
return Data{}, fmt.Errorf("CreateFileMapping %s: %w", f.Name(), err)
}
addr, err := syscall.MapViewOfFile(h, syscall.FILE_MAP_READ, 0, 0, 0)
if err != nil {
return Data{}, fmt.Errorf("MapViewOfFile %s: %w", f.Name(), err)
}
var info windows.MemoryBasicInformation
err = windows.VirtualQuery(addr, &info, unsafe.Sizeof(info))
if err != nil {
return Data{}, fmt.Errorf("VirtualQuery %s: %w", f.Name(), err)
}
data := unsafe.Slice((*byte)(unsafe.Pointer(addr)), int(info.RegionSize))
return Data{f, data}, nil
}
|
