Add Go frontend, libgo library, and Go testsuite.

gcc/:
	* gcc.c (default_compilers): Add entry for ".go".
	* common.opt: Add -static-libgo as a driver option.
	* doc/install.texi (Configuration): Mention libgo as an option for
	--enable-shared.  Mention go as an option for --enable-languages.
	* doc/invoke.texi (Overall Options): Mention .go as a file name
	suffix.  Mention go as a -x option.
	* doc/frontends.texi (G++ and GCC): Mention Go as a supported
	language.
	* doc/sourcebuild.texi (Top Level): Mention libgo.
	* doc/standards.texi (Standards): Add section on Go language.
	Move references for other languages into their own section.
	* doc/contrib.texi (Contributors): Mention that I contributed the
	Go frontend.
gcc/testsuite/:
	* lib/go.exp: New file.
	* lib/go-dg.exp: New file.
	* lib/go-torture.exp: New file.
	* lib/target-supports.exp (check_compile): Match // Go.

From-SVN: r167407

2 files changed, 125 insertions, 0 deletions

diff --git a/libgo/go/crypto/rc4/rc4.go b/libgo/go/crypto/rc4/rc4.go
new file mode 100644
index 0000000..e47a015
--- /dev/null
+++ b/libgo/go/crypto/rc4/rc4.go
@@ -0,0 +1,66 @@
+// 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.
+
+// This package implements RC4 encryption, as defined in Bruce Schneier's
+// Applied Cryptography.
+package rc4
+
+// BUG(agl): RC4 is in common use but has design weaknesses that make
+// it a poor choice for new protocols.
+
+import (
+	"os"
+	"strconv"
+)
+
+// A Cipher is an instance of RC4 using a particular key.
+type Cipher struct {
+	s    [256]byte
+	i, j uint8
+}
+
+type KeySizeError int
+
+func (k KeySizeError) String() string {
+	return "crypto/rc4: invalid key size " + strconv.Itoa(int(k))
+}
+
+// NewCipher creates and returns a new Cipher.  The key argument should be the
+// RC4 key, at least 1 byte and at most 256 bytes.
+func NewCipher(key []byte) (*Cipher, os.Error) {
+	k := len(key)
+	if k < 1 || k > 256 {
+		return nil, KeySizeError(k)
+	}
+	var c Cipher
+	for i := 0; i < 256; i++ {
+		c.s[i] = uint8(i)
+	}
+	var j uint8 = 0
+	for i := 0; i < 256; i++ {
+		j += c.s[i] + key[i%k]
+		c.s[i], c.s[j] = c.s[j], c.s[i]
+	}
+	return &c, nil
+}
+
+// XORKeyStream will XOR each byte of the given buffer with a byte of the
+// generated keystream.
+func (c *Cipher) XORKeyStream(buf []byte) {
+	for i := range buf {
+		c.i += 1
+		c.j += c.s[c.i]
+		c.s[c.i], c.s[c.j] = c.s[c.j], c.s[c.i]
+		buf[i] ^= c.s[c.s[c.i]+c.s[c.j]]
+	}
+}
+
+// Reset zeros the key data so that it will no longer appear in the
+// process's memory.
+func (c *Cipher) Reset() {
+	for i := range c.s {
+		c.s[i] = 0
+	}
+	c.i, c.j = 0, 0
+}
diff --git a/libgo/go/crypto/rc4/rc4_test.go b/libgo/go/crypto/rc4/rc4_test.go
new file mode 100644
index 0000000..73a52e7
--- /dev/null
+++ b/libgo/go/crypto/rc4/rc4_test.go
@@ -0,0 +1,59 @@
+// 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.
+
+package rc4
+
+import (
+	"testing"
+)
+
+type rc4Test struct {
+	key, keystream []byte
+}
+
+var golden = []rc4Test{
+	// Test vectors from the original cypherpunk posting of ARC4:
+	//   http://groups.google.com/group/sci.crypt/msg/10a300c9d21afca0?pli=1
+	{
+		[]byte{0x01, 0x23, 0x45, 0x67, 0x89, 0xab, 0xcd, 0xef},
+		[]byte{0x74, 0x94, 0xc2, 0xe7, 0x10, 0x4b, 0x08, 0x79},
+	},
+	{
+		[]byte{0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00},
+		[]byte{0xde, 0x18, 0x89, 0x41, 0xa3, 0x37, 0x5d, 0x3a},
+	},
+	{
+		[]byte{0xef, 0x01, 0x23, 0x45},
+		[]byte{0xd6, 0xa1, 0x41, 0xa7, 0xec, 0x3c, 0x38, 0xdf, 0xbd, 0x61},
+	},
+
+	// Test vectors from the Wikipedia page: http://en.wikipedia.org/wiki/RC4
+	{
+		[]byte{0x4b, 0x65, 0x79},
+		[]byte{0xeb, 0x9f, 0x77, 0x81, 0xb7, 0x34, 0xca, 0x72, 0xa7, 0x19},
+	},
+	{
+		[]byte{0x57, 0x69, 0x6b, 0x69},
+		[]byte{0x60, 0x44, 0xdb, 0x6d, 0x41, 0xb7},
+	},
+}
+
+func TestGolden(t *testing.T) {
+	for i := 0; i < len(golden); i++ {
+		g := golden[i]
+		c, err := NewCipher(g.key)
+		if err != nil {
+			t.Errorf("Failed to create cipher at golden index %d", i)
+			return
+		}
+		keystream := make([]byte, len(g.keystream))
+		c.XORKeyStream(keystream)
+		for j, v := range keystream {
+			if g.keystream[j] != v {
+				t.Errorf("Failed at golden index %d", i)
+				break
+			}
+		}
+	}
+}