1 files changed, 98 insertions, 0 deletions
diff --git a/src/pkg/os/env_windows.go b/src/pkg/os/env_windows.go
index 7d5b007c9..d2b159dfb 100755..100644
--- a/src/pkg/os/env_windows.go
+++ b/src/pkg/os/env_windows.go
@@ -9,8 +9,92 @@ package os
 import (
 	"syscall"
 	"utf16"
+	"unsafe"
 )
 
+// ENOENV is the Error indicating that an environment variable does not exist.
+var ENOENV = NewError("no such environment variable")
+
+// Getenverror retrieves the value of the environment variable named by the key.
+// It returns the value and an error, if any.
+func Getenverror(key string) (value string, err Error) {
+	b := make([]uint16, 100)
+	n, e := syscall.GetEnvironmentVariable(syscall.StringToUTF16Ptr(key), &b[0], uint32(len(b)))
+	if n == 0 && e == syscall.ERROR_ENVVAR_NOT_FOUND {
+		return "", ENOENV
+	}
+	if n > uint32(len(b)) {
+		b = make([]uint16, n)
+		n, e = syscall.GetEnvironmentVariable(syscall.StringToUTF16Ptr(key), &b[0], uint32(len(b)))
+		if n > uint32(len(b)) {
+			n = 0
+		}
+	}
+	if n == 0 {
+		return "", NewSyscallError("GetEnvironmentVariable", e)
+	}
+	return string(utf16.Decode(b[0:n])), nil
+}
+
+// Getenv retrieves the value of the environment variable named by the key.
+// It returns the value, which will be empty if the variable is not present.
+func Getenv(key string) string {
+	v, _ := Getenverror(key)
+	return v
+}
+
+// Setenv sets the value of the environment variable named by the key.
+// It returns an Error, if any.
+func Setenv(key, value string) Error {
+	var v *uint16
+	if len(value) > 0 {
+		v = syscall.StringToUTF16Ptr(value)
+	}
+	ok, e := syscall.SetEnvironmentVariable(syscall.StringToUTF16Ptr(key), v)
+	if !ok {
+		return NewSyscallError("SetEnvironmentVariable", e)
+	}
+	return nil
+}
+
+// Clearenv deletes all environment variables.
+func Clearenv() {
+	for _, s := range Environ() {
+		// Environment variables can begin with =
+		// so start looking for the separator = at j=1.
+		// http://blogs.msdn.com/b/oldnewthing/archive/2010/05/06/10008132.aspx
+		for j := 1; j < len(s); j++ {
+			if s[j] == '=' {
+				Setenv(s[0:j], "")
+				break
+			}
+		}
+	}
+}
+
+// Environ returns an array of strings representing the environment,
+// in the form "key=value".
+func Environ() []string {
+	s, e := syscall.GetEnvironmentStrings()
+	if e != 0 {
+		return nil
+	}
+	defer syscall.FreeEnvironmentStrings(s)
+	r := make([]string, 0, 50) // Empty with room to grow.
+	for from, i, p := 0, 0, (*[1 << 24]uint16)(unsafe.Pointer(s)); true; i++ {
+		if p[i] == 0 {
+			// empty string marks the end
+			if i <= from {
+				break
+			}
+			r = append(r, string(utf16.Decode(p[from:i])))
+			from = i + 1
+		}
+	}
+	return r
+}
+
+// TempDir returns the default directory to use for temporary files.
 func TempDir() string {
 	const pathSep = '\\'
 	dirw := make([]uint16, syscall.MAX_PATH)
@@ -27,3 +111,17 @@ func TempDir() string {
 	}
 	return string(utf16.Decode(dirw[0:n]))
 }
+
+func init() {
+	var argc int32
+	cmd := syscall.GetCommandLine()
+	argv, e := syscall.CommandLineToArgv(cmd, &argc)
+	if e != 0 {
+		return
+	}
+	defer syscall.LocalFree(uint32(uintptr(unsafe.Pointer(argv))))
+	Args = make([]string, argc)
+	for i, v := range (*argv)[:argc] {
+		Args[i] = string(syscall.UTF16ToString((*v)[:]))
+	}
+}