50 lines
1.1 KiB
Go
50 lines
1.1 KiB
Go
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// Copyright 2017 The Memory Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style
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// license that can be found in the LICENSE file.
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package memory // import "modernc.org/memory"
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import (
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"os"
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"syscall"
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)
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const (
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_MEM_COMMIT = 0x1000
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_MEM_RESERVE = 0x2000
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_MEM_DECOMMIT = 0x4000
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_MEM_RELEASE = 0x8000
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_PAGE_READWRITE = 0x0004
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_PAGE_NOACCESS = 0x0001
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)
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const pageSizeLog = 16
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var (
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modkernel32 = syscall.NewLazyDLL("kernel32.dll")
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osPageMask = osPageSize - 1
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osPageSize = os.Getpagesize()
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procVirtualAlloc = modkernel32.NewProc("VirtualAlloc")
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procVirtualFree = modkernel32.NewProc("VirtualFree")
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)
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// pageSize aligned.
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func mmap(size int) (uintptr, int, error) {
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size = roundup(size, pageSize)
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addr, _, err := procVirtualAlloc.Call(0, uintptr(size), _MEM_COMMIT|_MEM_RESERVE, _PAGE_READWRITE)
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if err.(syscall.Errno) != 0 || addr == 0 {
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return addr, size, err
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}
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return addr, size, nil
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}
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func unmap(addr uintptr, size int) error {
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r, _, err := procVirtualFree.Call(addr, 0, _MEM_RELEASE)
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if r == 0 {
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return err
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}
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return nil
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}
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