libgo: update to Go 1.11

    
    Reviewed-on: https://go-review.googlesource.com/136435

gotools/:
	* Makefile.am (mostlyclean-local): Run chmod on check-go-dir to
	make sure it is writable.
	(check-go-tools): Likewise.
	(check-vet): Copy internal/objabi to check-vet-dir.
	* Makefile.in: Rebuild.

From-SVN: r264546

4 files changed, 63 insertions, 24 deletions

diff --git a/libgo/go/io/io.go b/libgo/go/io/io.go
index 27482de..72b7581 100644
--- a/libgo/go/io/io.go
+++ b/libgo/go/io/io.go
@@ -300,6 +300,7 @@ func WriteString(w Writer, s string) (n int, err error) {
 // ReadAtLeast returns ErrUnexpectedEOF.
 // If min is greater than the length of buf, ReadAtLeast returns ErrShortBuffer.
 // On return, n >= min if and only if err == nil.
+// If r returns an error having read at least min bytes, the error is dropped.
 func ReadAtLeast(r Reader, buf []byte, min int) (n int, err error) {
 	if len(buf) < min {
 		return 0, ErrShortBuffer
@@ -323,6 +324,7 @@ func ReadAtLeast(r Reader, buf []byte, min int) (n int, err error) {
 // If an EOF happens after reading some but not all the bytes,
 // ReadFull returns ErrUnexpectedEOF.
 // On return, n == len(buf) if and only if err == nil.
+// If r returns an error having read at least len(buf) bytes, the error is dropped.
 func ReadFull(r Reader, buf []byte) (n int, err error) {
 	return ReadAtLeast(r, buf, len(buf))
 }
@@ -385,15 +387,15 @@ func copyBuffer(dst Writer, src Reader, buf []byte) (written int64, err error) {
 	if rt, ok := dst.(ReaderFrom); ok {
 		return rt.ReadFrom(src)
 	}
-	size := 32 * 1024
-	if l, ok := src.(*LimitedReader); ok && int64(size) > l.N {
-		if l.N < 1 {
-			size = 1
-		} else {
-			size = int(l.N)
-		}
-	}
 	if buf == nil {
+		size := 32 * 1024
+		if l, ok := src.(*LimitedReader); ok && int64(size) > l.N {
+			if l.N < 1 {
+				size = 1
+			} else {
+				size = int(l.N)
+			}
+		}
 		buf = make([]byte, size)
 	}
 	for {
diff --git a/libgo/go/io/ioutil/example_test.go b/libgo/go/io/ioutil/example_test.go
index 6edfec1..4cc7a7f 100644
--- a/libgo/go/io/ioutil/example_test.go
+++ b/libgo/go/io/ioutil/example_test.go
@@ -72,6 +72,24 @@ func ExampleTempFile() {
 	}
 }
 
+func ExampleTempFile_suffix() {
+	content := []byte("temporary file's content")
+	tmpfile, err := ioutil.TempFile("", "example.*.txt")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	defer os.Remove(tmpfile.Name()) // clean up
+
+	if _, err := tmpfile.Write(content); err != nil {
+		tmpfile.Close()
+		log.Fatal(err)
+	}
+	if err := tmpfile.Close(); err != nil {
+		log.Fatal(err)
+	}
+}
+
 func ExampleReadFile() {
 	content, err := ioutil.ReadFile("testdata/hello")
 	if err != nil {
diff --git a/libgo/go/io/ioutil/tempfile.go b/libgo/go/io/ioutil/tempfile.go
index e5e315c..ba8783b 100644
--- a/libgo/go/io/ioutil/tempfile.go
+++ b/libgo/go/io/ioutil/tempfile.go
@@ -8,6 +8,7 @@ import (
 	"os"
 	"path/filepath"
 	"strconv"
+	"strings"
 	"sync"
 	"time"
 )
@@ -23,7 +24,7 @@ func reseed() uint32 {
 	return uint32(time.Now().UnixNano() + int64(os.Getpid()))
 }
 
-func nextSuffix() string {
+func nextRandom() string {
 	randmu.Lock()
 	r := rand
 	if r == 0 {
@@ -35,23 +36,32 @@ func nextSuffix() string {
 	return strconv.Itoa(int(1e9 + r%1e9))[1:]
 }
 
-// TempFile creates a new temporary file in the directory dir
-// with a name beginning with prefix, opens the file for reading
-// and writing, and returns the resulting *os.File.
+// TempFile creates a new temporary file in the directory dir,
+// opens the file for reading and writing, and returns the resulting *os.File.
+// The filename is generated by taking pattern and adding a random
+// string to the end. If pattern includes a "*", the random string
+// replaces the last "*".
 // If dir is the empty string, TempFile uses the default directory
 // for temporary files (see os.TempDir).
 // Multiple programs calling TempFile simultaneously
 // will not choose the same file. The caller can use f.Name()
 // to find the pathname of the file. It is the caller's responsibility
 // to remove the file when no longer needed.
-func TempFile(dir, prefix string) (f *os.File, err error) {
+func TempFile(dir, pattern string) (f *os.File, err error) {
 	if dir == "" {
 		dir = os.TempDir()
 	}
 
+	var prefix, suffix string
+	if pos := strings.LastIndex(pattern, "*"); pos != -1 {
+		prefix, suffix = pattern[:pos], pattern[pos+1:]
+	} else {
+		prefix = pattern
+	}
+
 	nconflict := 0
 	for i := 0; i < 10000; i++ {
-		name := filepath.Join(dir, prefix+nextSuffix())
+		name := filepath.Join(dir, prefix+nextRandom()+suffix)
 		f, err = os.OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0600)
 		if os.IsExist(err) {
 			if nconflict++; nconflict > 10 {
@@ -80,7 +90,7 @@ func TempDir(dir, prefix string) (name string, err error) {
 
 	nconflict := 0
 	for i := 0; i < 10000; i++ {
-		try := filepath.Join(dir, prefix+nextSuffix())
+		try := filepath.Join(dir, prefix+nextRandom())
 		err = os.Mkdir(try, 0700)
 		if os.IsExist(err) {
 			if nconflict++; nconflict > 10 {
diff --git a/libgo/go/io/ioutil/tempfile_test.go b/libgo/go/io/ioutil/tempfile_test.go
index 9d54bad..0758890 100644
--- a/libgo/go/io/ioutil/tempfile_test.go
+++ b/libgo/go/io/ioutil/tempfile_test.go
@@ -8,6 +8,7 @@ import (
 	"os"
 	"path/filepath"
 	"regexp"
+	"strings"
 	"testing"
 )
 
@@ -23,18 +24,26 @@ func TestTempFile(t *testing.T) {
 	if f != nil || err == nil {
 		t.Errorf("TempFile(%q, `foo`) = %v, %v", nonexistentDir, f, err)
 	}
+}
 
-	dir = os.TempDir()
-	f, err = TempFile(dir, "ioutil_test")
-	if f == nil || err != nil {
-		t.Errorf("TempFile(dir, `ioutil_test`) = %v, %v", f, err)
+func TestTempFile_pattern(t *testing.T) {
+	tests := []struct{ pattern, prefix, suffix string }{
+		{"ioutil_test", "ioutil_test", ""},
+		{"ioutil_test*", "ioutil_test", ""},
+		{"ioutil_test*xyz", "ioutil_test", "xyz"},
 	}
-	if f != nil {
+	for _, test := range tests {
+		f, err := TempFile("", test.pattern)
+		if err != nil {
+			t.Errorf("TempFile(..., %q) error: %v", test.pattern, err)
+			continue
+		}
+		defer os.Remove(f.Name())
+		base := filepath.Base(f.Name())
 		f.Close()
-		os.Remove(f.Name())
-		re := regexp.MustCompile("^" + regexp.QuoteMeta(filepath.Join(dir, "ioutil_test")) + "[0-9]+$")
-		if !re.MatchString(f.Name()) {
-			t.Errorf("TempFile(`"+dir+"`, `ioutil_test`) created bad name %s", f.Name())
+		if !(strings.HasPrefix(base, test.prefix) && strings.HasSuffix(base, test.suffix)) {
+			t.Errorf("TempFile pattern %q created bad name %q; want prefix %q & suffix %q",
+				test.pattern, base, test.prefix, test.suffix)
 		}
 	}
 }