vendor/golang.org/x/sys/windows/exec_windows.go
changeset 265 05c40b36d3b2
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/vendor/golang.org/x/sys/windows/exec_windows.go	Sat Feb 04 12:58:35 2023 +0100
@@ -0,0 +1,178 @@
+// Copyright 2009 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.
+
+// Fork, exec, wait, etc.
+
+package windows
+
+import (
+	errorspkg "errors"
+	"unsafe"
+)
+
+// EscapeArg rewrites command line argument s as prescribed
+// in http://msdn.microsoft.com/en-us/library/ms880421.
+// This function returns "" (2 double quotes) if s is empty.
+// Alternatively, these transformations are done:
+//   - every back slash (\) is doubled, but only if immediately
+//     followed by double quote (");
+//   - every double quote (") is escaped by back slash (\);
+//   - finally, s is wrapped with double quotes (arg -> "arg"),
+//     but only if there is space or tab inside s.
+func EscapeArg(s string) string {
+	if len(s) == 0 {
+		return "\"\""
+	}
+	n := len(s)
+	hasSpace := false
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		case '"', '\\':
+			n++
+		case ' ', '\t':
+			hasSpace = true
+		}
+	}
+	if hasSpace {
+		n += 2
+	}
+	if n == len(s) {
+		return s
+	}
+
+	qs := make([]byte, n)
+	j := 0
+	if hasSpace {
+		qs[j] = '"'
+		j++
+	}
+	slashes := 0
+	for i := 0; i < len(s); i++ {
+		switch s[i] {
+		default:
+			slashes = 0
+			qs[j] = s[i]
+		case '\\':
+			slashes++
+			qs[j] = s[i]
+		case '"':
+			for ; slashes > 0; slashes-- {
+				qs[j] = '\\'
+				j++
+			}
+			qs[j] = '\\'
+			j++
+			qs[j] = s[i]
+		}
+		j++
+	}
+	if hasSpace {
+		for ; slashes > 0; slashes-- {
+			qs[j] = '\\'
+			j++
+		}
+		qs[j] = '"'
+		j++
+	}
+	return string(qs[:j])
+}
+
+// ComposeCommandLine escapes and joins the given arguments suitable for use as a Windows command line,
+// in CreateProcess's CommandLine argument, CreateService/ChangeServiceConfig's BinaryPathName argument,
+// or any program that uses CommandLineToArgv.
+func ComposeCommandLine(args []string) string {
+	var commandLine string
+	for i := range args {
+		if i > 0 {
+			commandLine += " "
+		}
+		commandLine += EscapeArg(args[i])
+	}
+	return commandLine
+}
+
+// DecomposeCommandLine breaks apart its argument command line into unescaped parts using CommandLineToArgv,
+// as gathered from GetCommandLine, QUERY_SERVICE_CONFIG's BinaryPathName argument, or elsewhere that
+// command lines are passed around.
+func DecomposeCommandLine(commandLine string) ([]string, error) {
+	if len(commandLine) == 0 {
+		return []string{}, nil
+	}
+	var argc int32
+	argv, err := CommandLineToArgv(StringToUTF16Ptr(commandLine), &argc)
+	if err != nil {
+		return nil, err
+	}
+	defer LocalFree(Handle(unsafe.Pointer(argv)))
+	var args []string
+	for _, v := range (*argv)[:argc] {
+		args = append(args, UTF16ToString((*v)[:]))
+	}
+	return args, nil
+}
+
+func CloseOnExec(fd Handle) {
+	SetHandleInformation(Handle(fd), HANDLE_FLAG_INHERIT, 0)
+}
+
+// FullPath retrieves the full path of the specified file.
+func FullPath(name string) (path string, err error) {
+	p, err := UTF16PtrFromString(name)
+	if err != nil {
+		return "", err
+	}
+	n := uint32(100)
+	for {
+		buf := make([]uint16, n)
+		n, err = GetFullPathName(p, uint32(len(buf)), &buf[0], nil)
+		if err != nil {
+			return "", err
+		}
+		if n <= uint32(len(buf)) {
+			return UTF16ToString(buf[:n]), nil
+		}
+	}
+}
+
+// NewProcThreadAttributeList allocates a new ProcThreadAttributeListContainer, with the requested maximum number of attributes.
+func NewProcThreadAttributeList(maxAttrCount uint32) (*ProcThreadAttributeListContainer, error) {
+	var size uintptr
+	err := initializeProcThreadAttributeList(nil, maxAttrCount, 0, &size)
+	if err != ERROR_INSUFFICIENT_BUFFER {
+		if err == nil {
+			return nil, errorspkg.New("unable to query buffer size from InitializeProcThreadAttributeList")
+		}
+		return nil, err
+	}
+	alloc, err := LocalAlloc(LMEM_FIXED, uint32(size))
+	if err != nil {
+		return nil, err
+	}
+	// size is guaranteed to be ≥1 by InitializeProcThreadAttributeList.
+	al := &ProcThreadAttributeListContainer{data: (*ProcThreadAttributeList)(unsafe.Pointer(alloc))}
+	err = initializeProcThreadAttributeList(al.data, maxAttrCount, 0, &size)
+	if err != nil {
+		return nil, err
+	}
+	return al, err
+}
+
+// Update modifies the ProcThreadAttributeList using UpdateProcThreadAttribute.
+func (al *ProcThreadAttributeListContainer) Update(attribute uintptr, value unsafe.Pointer, size uintptr) error {
+	al.pointers = append(al.pointers, value)
+	return updateProcThreadAttribute(al.data, 0, attribute, value, size, nil, nil)
+}
+
+// Delete frees ProcThreadAttributeList's resources.
+func (al *ProcThreadAttributeListContainer) Delete() {
+	deleteProcThreadAttributeList(al.data)
+	LocalFree(Handle(unsafe.Pointer(al.data)))
+	al.data = nil
+	al.pointers = nil
+}
+
+// List returns the actual ProcThreadAttributeList to be passed to StartupInfoEx.
+func (al *ProcThreadAttributeListContainer) List() *ProcThreadAttributeList {
+	return al.data
+}