7 files changed, 489 insertions, 0 deletions
diff --git a/src/os/user/lookup.go b/src/os/user/lookup.go
new file mode 100644
index 000000000..09f00c7bd
--- /dev/null
+++ b/src/os/user/lookup.go
@@ -0,0 +1,22 @@
+// 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 user
+
+// Current returns the current user.
+func Current() (*User, error) {
+	return current()
+}
+
+// Lookup looks up a user by username. If the user cannot be found, the
+// returned error is of type UnknownUserError.
+func Lookup(username string) (*User, error) {
+	return lookup(username)
+}
+
+// LookupId looks up a user by userid. If the user cannot be found, the
+// returned error is of type UnknownUserIdError.
+func LookupId(uid string) (*User, error) {
+	return lookupId(uid)
+}
diff --git a/src/os/user/lookup_plan9.go b/src/os/user/lookup_plan9.go
new file mode 100644
index 000000000..f7ef3482b
--- /dev/null
+++ b/src/os/user/lookup_plan9.go
@@ -0,0 +1,46 @@
+// Copyright 2013 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 user
+
+import (
+	"fmt"
+	"io/ioutil"
+	"os"
+	"syscall"
+)
+
+// Partial os/user support on Plan 9.
+// Supports Current(), but not Lookup()/LookupId().
+// The latter two would require parsing /adm/users.
+const (
+	userFile = "/dev/user"
+)
+
+func current() (*User, error) {
+	ubytes, err := ioutil.ReadFile(userFile)
+	if err != nil {
+		return nil, fmt.Errorf("user: %s", err)
+	}
+
+	uname := string(ubytes)
+
+	u := &User{
+		Uid:      uname,
+		Gid:      uname,
+		Username: uname,
+		Name:     uname,
+		HomeDir:  os.Getenv("home"),
+	}
+
+	return u, nil
+}
+
+func lookup(username string) (*User, error) {
+	return nil, syscall.EPLAN9
+}
+
+func lookupId(uid string) (*User, error) {
+	return nil, syscall.EPLAN9
+}
diff --git a/src/os/user/lookup_stubs.go b/src/os/user/lookup_stubs.go
new file mode 100644
index 000000000..4fb0e3c6e
--- /dev/null
+++ b/src/os/user/lookup_stubs.go
@@ -0,0 +1,28 @@
+// 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.
+
+// +build !cgo,!windows,!plan9 android
+
+package user
+
+import (
+	"fmt"
+	"runtime"
+)
+
+func init() {
+	implemented = false
+}
+
+func current() (*User, error) {
+	return nil, fmt.Errorf("user: Current not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func lookup(username string) (*User, error) {
+	return nil, fmt.Errorf("user: Lookup not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
+
+func lookupId(uid string) (*User, error) {
+	return nil, fmt.Errorf("user: LookupId not implemented on %s/%s", runtime.GOOS, runtime.GOARCH)
+}
diff --git a/src/os/user/lookup_unix.go b/src/os/user/lookup_unix.go
new file mode 100644
index 000000000..0871473df
--- /dev/null
+++ b/src/os/user/lookup_unix.go
@@ -0,0 +1,112 @@
+// 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.
+
+// +build darwin dragonfly freebsd !android,linux netbsd openbsd solaris
+// +build cgo
+
+package user
+
+import (
+	"fmt"
+	"runtime"
+	"strconv"
+	"strings"
+	"syscall"
+	"unsafe"
+)
+
+/*
+#include <unistd.h>
+#include <sys/types.h>
+#include <pwd.h>
+#include <stdlib.h>
+
+static int mygetpwuid_r(int uid, struct passwd *pwd,
+	char *buf, size_t buflen, struct passwd **result) {
+ return getpwuid_r(uid, pwd, buf, buflen, result);
+}
+*/
+import "C"
+
+func current() (*User, error) {
+	return lookupUnix(syscall.Getuid(), "", false)
+}
+
+func lookup(username string) (*User, error) {
+	return lookupUnix(-1, username, true)
+}
+
+func lookupId(uid string) (*User, error) {
+	i, e := strconv.Atoi(uid)
+	if e != nil {
+		return nil, e
+	}
+	return lookupUnix(i, "", false)
+}
+
+func lookupUnix(uid int, username string, lookupByName bool) (*User, error) {
+	var pwd C.struct_passwd
+	var result *C.struct_passwd
+
+	var bufSize C.long
+	if runtime.GOOS == "dragonfly" || runtime.GOOS == "freebsd" {
+		// DragonFly and FreeBSD do not have _SC_GETPW_R_SIZE_MAX
+		// and just return -1.  So just use the same
+		// size that Linux returns.
+		bufSize = 1024
+	} else {
+		bufSize = C.sysconf(C._SC_GETPW_R_SIZE_MAX)
+		if bufSize <= 0 || bufSize > 1<<20 {
+			return nil, fmt.Errorf("user: unreasonable _SC_GETPW_R_SIZE_MAX of %d", bufSize)
+		}
+	}
+	buf := C.malloc(C.size_t(bufSize))
+	defer C.free(buf)
+	var rv C.int
+	if lookupByName {
+		nameC := C.CString(username)
+		defer C.free(unsafe.Pointer(nameC))
+		rv = C.getpwnam_r(nameC,
+			&pwd,
+			(*C.char)(buf),
+			C.size_t(bufSize),
+			&result)
+		if rv != 0 {
+			return nil, fmt.Errorf("user: lookup username %s: %s", username, syscall.Errno(rv))
+		}
+		if result == nil {
+			return nil, UnknownUserError(username)
+		}
+	} else {
+		// mygetpwuid_r is a wrapper around getpwuid_r to
+		// to avoid using uid_t because C.uid_t(uid) for
+		// unknown reasons doesn't work on linux.
+		rv = C.mygetpwuid_r(C.int(uid),
+			&pwd,
+			(*C.char)(buf),
+			C.size_t(bufSize),
+			&result)
+		if rv != 0 {
+			return nil, fmt.Errorf("user: lookup userid %d: %s", uid, syscall.Errno(rv))
+		}
+		if result == nil {
+			return nil, UnknownUserIdError(uid)
+		}
+	}
+	u := &User{
+		Uid:      strconv.Itoa(int(pwd.pw_uid)),
+		Gid:      strconv.Itoa(int(pwd.pw_gid)),
+		Username: C.GoString(pwd.pw_name),
+		Name:     C.GoString(pwd.pw_gecos),
+		HomeDir:  C.GoString(pwd.pw_dir),
+	}
+	// The pw_gecos field isn't quite standardized.  Some docs
+	// say: "It is expected to be a comma separated list of
+	// personal data where the first item is the full name of the
+	// user."
+	if i := strings.Index(u.Name, ","); i >= 0 {
+		u.Name = u.Name[:i]
+	}
+	return u, nil
+}
diff --git a/src/os/user/lookup_windows.go b/src/os/user/lookup_windows.go
new file mode 100644
index 000000000..99c325ff0
--- /dev/null
+++ b/src/os/user/lookup_windows.go
@@ -0,0 +1,149 @@
+// Copyright 2012 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 user
+
+import (
+	"fmt"
+	"syscall"
+	"unsafe"
+)
+
+func isDomainJoined() (bool, error) {
+	var domain *uint16
+	var status uint32
+	err := syscall.NetGetJoinInformation(nil, &domain, &status)
+	if err != nil {
+		return false, err
+	}
+	syscall.NetApiBufferFree((*byte)(unsafe.Pointer(domain)))
+	return status == syscall.NetSetupDomainName, nil
+}
+
+func lookupFullNameDomain(domainAndUser string) (string, error) {
+	return syscall.TranslateAccountName(domainAndUser,
+		syscall.NameSamCompatible, syscall.NameDisplay, 50)
+}
+
+func lookupFullNameServer(servername, username string) (string, error) {
+	s, e := syscall.UTF16PtrFromString(servername)
+	if e != nil {
+		return "", e
+	}
+	u, e := syscall.UTF16PtrFromString(username)
+	if e != nil {
+		return "", e
+	}
+	var p *byte
+	e = syscall.NetUserGetInfo(s, u, 10, &p)
+	if e != nil {
+		return "", e
+	}
+	defer syscall.NetApiBufferFree(p)
+	i := (*syscall.UserInfo10)(unsafe.Pointer(p))
+	if i.FullName == nil {
+		return "", nil
+	}
+	name := syscall.UTF16ToString((*[1024]uint16)(unsafe.Pointer(i.FullName))[:])
+	return name, nil
+}
+
+func lookupFullName(domain, username, domainAndUser string) (string, error) {
+	joined, err := isDomainJoined()
+	if err == nil && joined {
+		name, err := lookupFullNameDomain(domainAndUser)
+		if err == nil {
+			return name, nil
+		}
+	}
+	name, err := lookupFullNameServer(domain, username)
+	if err == nil {
+		return name, nil
+	}
+	// domain worked neigher as a domain nor as a server
+	// could be domain server unavailable
+	// pretend username is fullname
+	return username, nil
+}
+
+func newUser(usid *syscall.SID, gid, dir string) (*User, error) {
+	username, domain, t, e := usid.LookupAccount("")
+	if e != nil {
+		return nil, e
+	}
+	if t != syscall.SidTypeUser {
+		return nil, fmt.Errorf("user: should be user account type, not %d", t)
+	}
+	domainAndUser := domain + `\` + username
+	uid, e := usid.String()
+	if e != nil {
+		return nil, e
+	}
+	name, e := lookupFullName(domain, username, domainAndUser)
+	if e != nil {
+		return nil, e
+	}
+	u := &User{
+		Uid:      uid,
+		Gid:      gid,
+		Username: domainAndUser,
+		Name:     name,
+		HomeDir:  dir,
+	}
+	return u, nil
+}
+
+func current() (*User, error) {
+	t, e := syscall.OpenCurrentProcessToken()
+	if e != nil {
+		return nil, e
+	}
+	defer t.Close()
+	u, e := t.GetTokenUser()
+	if e != nil {
+		return nil, e
+	}
+	pg, e := t.GetTokenPrimaryGroup()
+	if e != nil {
+		return nil, e
+	}
+	gid, e := pg.PrimaryGroup.String()
+	if e != nil {
+		return nil, e
+	}
+	dir, e := t.GetUserProfileDirectory()
+	if e != nil {
+		return nil, e
+	}
+	return newUser(u.User.Sid, gid, dir)
+}
+
+// BUG(brainman): Lookup and LookupId functions do not set
+// Gid and HomeDir fields in the User struct returned on windows.
+
+func newUserFromSid(usid *syscall.SID) (*User, error) {
+	// TODO(brainman): do not know where to get gid and dir fields
+	gid := "unknown"
+	dir := "Unknown directory"
+	return newUser(usid, gid, dir)
+}
+
+func lookup(username string) (*User, error) {
+	sid, _, t, e := syscall.LookupSID("", username)
+	if e != nil {
+		return nil, e
+	}
+	if t != syscall.SidTypeUser {
+		return nil, fmt.Errorf("user: should be user account type, not %d", t)
+	}
+	return newUserFromSid(sid)
+}
+
+func lookupId(uid string) (*User, error) {
+	sid, e := syscall.StringToSid(uid)
+	if e != nil {
+		return nil, e
+	}
+	return newUserFromSid(sid)
+}
diff --git a/src/os/user/user.go b/src/os/user/user.go
new file mode 100644
index 000000000..e8680fe54
--- /dev/null
+++ b/src/os/user/user.go
@@ -0,0 +1,43 @@
+// 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 user allows user account lookups by name or id.
+package user
+
+import (
+	"strconv"
+)
+
+var implemented = true // set to false by lookup_stubs.go's init
+
+// User represents a user account.
+//
+// On posix systems Uid and Gid contain a decimal number
+// representing uid and gid. On windows Uid and Gid
+// contain security identifier (SID) in a string format.
+// On Plan 9, Uid, Gid, Username, and Name will be the
+// contents of /dev/user.
+type User struct {
+	Uid      string // user id
+	Gid      string // primary group id
+	Username string
+	Name     string
+	HomeDir  string
+}
+
+// UnknownUserIdError is returned by LookupId when
+// a user cannot be found.
+type UnknownUserIdError int
+
+func (e UnknownUserIdError) Error() string {
+	return "user: unknown userid " + strconv.Itoa(int(e))
+}
+
+// UnknownUserError is returned by Lookup when
+// a user cannot be found.
+type UnknownUserError string
+
+func (e UnknownUserError) Error() string {
+	return "user: unknown user " + string(e)
+}
diff --git a/src/os/user/user_test.go b/src/os/user/user_test.go
new file mode 100644
index 000000000..9d9420e80
--- /dev/null
+++ b/src/os/user/user_test.go
@@ -0,0 +1,89 @@
+// 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 user
+
+import (
+	"runtime"
+	"testing"
+)
+
+func check(t *testing.T) {
+	if !implemented {
+		t.Skip("user: not implemented; skipping tests")
+	}
+}
+
+func TestCurrent(t *testing.T) {
+	check(t)
+
+	u, err := Current()
+	if err != nil {
+		t.Fatalf("Current: %v", err)
+	}
+	if u.HomeDir == "" {
+		t.Errorf("didn't get a HomeDir")
+	}
+	if u.Username == "" {
+		t.Errorf("didn't get a username")
+	}
+}
+
+func compare(t *testing.T, want, got *User) {
+	if want.Uid != got.Uid {
+		t.Errorf("got Uid=%q; want %q", got.Uid, want.Uid)
+	}
+	if want.Username != got.Username {
+		t.Errorf("got Username=%q; want %q", got.Username, want.Username)
+	}
+	if want.Name != got.Name {
+		t.Errorf("got Name=%q; want %q", got.Name, want.Name)
+	}
+	// TODO(brainman): fix it once we know how.
+	if runtime.GOOS == "windows" {
+		t.Skip("skipping Gid and HomeDir comparisons")
+	}
+	if want.Gid != got.Gid {
+		t.Errorf("got Gid=%q; want %q", got.Gid, want.Gid)
+	}
+	if want.HomeDir != got.HomeDir {
+		t.Errorf("got HomeDir=%q; want %q", got.HomeDir, want.HomeDir)
+	}
+}
+
+func TestLookup(t *testing.T) {
+	check(t)
+
+	if runtime.GOOS == "plan9" {
+		t.Skipf("Lookup not implemented on %q", runtime.GOOS)
+	}
+
+	want, err := Current()
+	if err != nil {
+		t.Fatalf("Current: %v", err)
+	}
+	got, err := Lookup(want.Username)
+	if err != nil {
+		t.Fatalf("Lookup: %v", err)
+	}
+	compare(t, want, got)
+}
+
+func TestLookupId(t *testing.T) {
+	check(t)
+
+	if runtime.GOOS == "plan9" {
+		t.Skipf("LookupId not implemented on %q", runtime.GOOS)
+	}
+
+	want, err := Current()
+	if err != nil {
+		t.Fatalf("Current: %v", err)
+	}
+	got, err := LookupId(want.Uid)
+	if err != nil {
+		t.Fatalf("LookupId: %v", err)
+	}
+	compare(t, want, got)
+}