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1 files changed, 248 insertions, 0 deletions

diff --git a/vendor/golang.org/x/sys/windows/exec_windows.go b/vendor/golang.org/x/sys/windows/exec_windows.go
new file mode 100644
index 0000000..9cabbb6
--- /dev/null
+++ b/vendor/golang.org/x/sys/windows/exec_windows.go
@@ -0,0 +1,248 @@
+// 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 // Reserve space for quotes.
+	}
+	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 {
+	if len(args) == 0 {
+		return ""
+	}
+
+	// Per https://learn.microsoft.com/en-us/windows/win32/api/shellapi/nf-shellapi-commandlinetoargvw:
+	// “This function accepts command lines that contain a program name; the
+	// program name can be enclosed in quotation marks or not.”
+	//
+	// Unfortunately, it provides no means of escaping interior quotation marks
+	// within that program name, and we have no way to report them here.
+	prog := args[0]
+	mustQuote := len(prog) == 0
+	for i := 0; i < len(prog); i++ {
+		c := prog[i]
+		if c <= ' ' || (c == '"' && i == 0) {
+			// Force quotes for not only the ASCII space and tab as described in the
+			// MSDN article, but also ASCII control characters.
+			// The documentation for CommandLineToArgvW doesn't say what happens when
+			// the first argument is not a valid program name, but it empirically
+			// seems to drop unquoted control characters.
+			mustQuote = true
+			break
+		}
+	}
+	var commandLine []byte
+	if mustQuote {
+		commandLine = make([]byte, 0, len(prog)+2)
+		commandLine = append(commandLine, '"')
+		for i := 0; i < len(prog); i++ {
+			c := prog[i]
+			if c == '"' {
+				// This quote would interfere with our surrounding quotes.
+				// We have no way to report an error, so just strip out
+				// the offending character instead.
+				continue
+			}
+			commandLine = append(commandLine, c)
+		}
+		commandLine = append(commandLine, '"')
+	} else {
+		if len(args) == 1 {
+			// args[0] is a valid command line representing itself.
+			// No need to allocate a new slice or string for it.
+			return prog
+		}
+		commandLine = []byte(prog)
+	}
+
+	for _, arg := range args[1:] {
+		commandLine = append(commandLine, ' ')
+		// TODO(bcmills): since we're already appending to a slice, it would be nice
+		// to avoid the intermediate allocations of EscapeArg.
+		// Perhaps we can factor out an appendEscapedArg function.
+		commandLine = append(commandLine, EscapeArg(arg)...)
+	}
+	return string(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.
+// DecomposeCommandLine returns an error if commandLine contains NUL.
+func DecomposeCommandLine(commandLine string) ([]string, error) {
+	if len(commandLine) == 0 {
+		return []string{}, nil
+	}
+	utf16CommandLine, err := UTF16FromString(commandLine)
+	if err != nil {
+		return nil, errorspkg.New("string with NUL passed to DecomposeCommandLine")
+	}
+	var argc int32
+	argv, err := commandLineToArgv(&utf16CommandLine[0], &argc)
+	if err != nil {
+		return nil, err
+	}
+	defer LocalFree(Handle(unsafe.Pointer(argv)))
+
+	var args []string
+	for _, p := range unsafe.Slice(argv, argc) {
+		args = append(args, UTF16PtrToString(p))
+	}
+	return args, nil
+}
+
+// CommandLineToArgv parses a Unicode command line string and sets
+// argc to the number of parsed arguments.
+//
+// The returned memory should be freed using a single call to LocalFree.
+//
+// Note that although the return type of CommandLineToArgv indicates 8192
+// entries of up to 8192 characters each, the actual count of parsed arguments
+// may exceed 8192, and the documentation for CommandLineToArgvW does not mention
+// any bound on the lengths of the individual argument strings.
+// (See https://go.dev/issue/63236.)
+func CommandLineToArgv(cmd *uint16, argc *int32) (argv *[8192]*[8192]uint16, err error) {
+	argp, err := commandLineToArgv(cmd, argc)
+	argv = (*[8192]*[8192]uint16)(unsafe.Pointer(argp))
+	return argv, err
+}
+
+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
+}