Separate CScriptCompressor

6 files changed, 215 insertions, 195 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index c3e2f7ed82..efa55f0dc2 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -99,6 +99,7 @@ BITCOIN_CORE_H = \
   rpcprotocol.h \
   rpcserver.h \
   script/interpreter.h \
+  script/compressor.h \
   script/script.h \
   script/standard.h \
   scriptutils.h \
@@ -210,6 +211,7 @@ libbitcoin_common_a_SOURCES = \
   netbase.cpp \
   protocol.cpp \
   script/interpreter.cpp \
+  script/compressor.cpp \
   script/script.cpp \
   script/standard.cpp \
   scriptutils.cpp \
diff --git a/src/core.h b/src/core.h
index 0df75670fd..030eb17734 100644
--- a/src/core.h
+++ b/src/core.h
@@ -6,7 +6,8 @@
 #ifndef BITCOIN_CORE_H
 #define BITCOIN_CORE_H
 
-#include "scriptutils.h"
+#include "script/compressor.h"
+#include "script/script.h"
 #include "serialize.h"
 #include "uint256.h"
 
diff --git a/src/script/compressor.cpp b/src/script/compressor.cpp
new file mode 100644
index 0000000000..2f8df602bf
--- /dev/null
+++ b/src/script/compressor.cpp
@@ -0,0 +1,127 @@
+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2013 The Bitcoin developers
+// Distributed under the MIT/X11 software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#include "compressor.h"
+
+bool CScriptCompressor::IsToKeyID(CKeyID &hash) const
+{
+    if (script.size() == 25 && script[0] == OP_DUP && script[1] == OP_HASH160
+                            && script[2] == 20 && script[23] == OP_EQUALVERIFY
+                            && script[24] == OP_CHECKSIG) {
+        memcpy(&hash, &script[3], 20);
+        return true;
+    }
+    return false;
+}
+
+bool CScriptCompressor::IsToScriptID(CScriptID &hash) const
+{
+    if (script.size() == 23 && script[0] == OP_HASH160 && script[1] == 20
+                            && script[22] == OP_EQUAL) {
+        memcpy(&hash, &script[2], 20);
+        return true;
+    }
+    return false;
+}
+
+bool CScriptCompressor::IsToPubKey(CPubKey &pubkey) const
+{
+    if (script.size() == 35 && script[0] == 33 && script[34] == OP_CHECKSIG
+                            && (script[1] == 0x02 || script[1] == 0x03)) {
+        pubkey.Set(&script[1], &script[34]);
+        return true;
+    }
+    if (script.size() == 67 && script[0] == 65 && script[66] == OP_CHECKSIG
+                            && script[1] == 0x04) {
+        pubkey.Set(&script[1], &script[66]);
+        return pubkey.IsFullyValid(); // if not fully valid, a case that would not be compressible
+    }
+    return false;
+}
+
+bool CScriptCompressor::Compress(std::vector<unsigned char> &out) const
+{
+    CKeyID keyID;
+    if (IsToKeyID(keyID)) {
+        out.resize(21);
+        out[0] = 0x00;
+        memcpy(&out[1], &keyID, 20);
+        return true;
+    }
+    CScriptID scriptID;
+    if (IsToScriptID(scriptID)) {
+        out.resize(21);
+        out[0] = 0x01;
+        memcpy(&out[1], &scriptID, 20);
+        return true;
+    }
+    CPubKey pubkey;
+    if (IsToPubKey(pubkey)) {
+        out.resize(33);
+        memcpy(&out[1], &pubkey[1], 32);
+        if (pubkey[0] == 0x02 || pubkey[0] == 0x03) {
+            out[0] = pubkey[0];
+            return true;
+        } else if (pubkey[0] == 0x04) {
+            out[0] = 0x04 | (pubkey[64] & 0x01);
+            return true;
+        }
+    }
+    return false;
+}
+
+unsigned int CScriptCompressor::GetSpecialSize(unsigned int nSize) const
+{
+    if (nSize == 0 || nSize == 1)
+        return 20;
+    if (nSize == 2 || nSize == 3 || nSize == 4 || nSize == 5)
+        return 32;
+    return 0;
+}
+
+bool CScriptCompressor::Decompress(unsigned int nSize, const std::vector<unsigned char> &in)
+{
+    switch(nSize) {
+    case 0x00:
+        script.resize(25);
+        script[0] = OP_DUP;
+        script[1] = OP_HASH160;
+        script[2] = 20;
+        memcpy(&script[3], &in[0], 20);
+        script[23] = OP_EQUALVERIFY;
+        script[24] = OP_CHECKSIG;
+        return true;
+    case 0x01:
+        script.resize(23);
+        script[0] = OP_HASH160;
+        script[1] = 20;
+        memcpy(&script[2], &in[0], 20);
+        script[22] = OP_EQUAL;
+        return true;
+    case 0x02:
+    case 0x03:
+        script.resize(35);
+        script[0] = 33;
+        script[1] = nSize;
+        memcpy(&script[2], &in[0], 32);
+        script[34] = OP_CHECKSIG;
+        return true;
+    case 0x04:
+    case 0x05:
+        unsigned char vch[33] = {};
+        vch[0] = nSize - 2;
+        memcpy(&vch[1], &in[0], 32);
+        CPubKey pubkey(&vch[0], &vch[33]);
+        if (!pubkey.Decompress())
+            return false;
+        assert(pubkey.size() == 65);
+        script.resize(67);
+        script[0] = 65;
+        memcpy(&script[1], pubkey.begin(), 65);
+        script[66] = OP_CHECKSIG;
+        return true;
+    }
+    return false;
+}
diff --git a/src/script/compressor.h b/src/script/compressor.h
new file mode 100644
index 0000000000..f0a3754f02
--- /dev/null
+++ b/src/script/compressor.h
@@ -0,0 +1,84 @@
+// Copyright (c) 2009-2010 Satoshi Nakamoto
+// Copyright (c) 2009-2013 The Bitcoin developers
+// Distributed under the MIT/X11 software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef H_BITCOIN_SCRIPT_COMPRESSOR
+#define H_BITCOIN_SCRIPT_COMPRESSOR
+
+#include "script/script.h"
+
+/** Compact serializer for scripts.
+ *
+ *  It detects common cases and encodes them much more efficiently.
+ *  3 special cases are defined:
+ *  * Pay to pubkey hash (encoded as 21 bytes)
+ *  * Pay to script hash (encoded as 21 bytes)
+ *  * Pay to pubkey starting with 0x02, 0x03 or 0x04 (encoded as 33 bytes)
+ *
+ *  Other scripts up to 121 bytes require 1 byte + script length. Above
+ *  that, scripts up to 16505 bytes require 2 bytes + script length.
+ */
+class CScriptCompressor
+{
+private:
+    // make this static for now (there are only 6 special scripts defined)
+    // this can potentially be extended together with a new nVersion for
+    // transactions, in which case this value becomes dependent on nVersion
+    // and nHeight of the enclosing transaction.
+    static const unsigned int nSpecialScripts = 6;
+
+    CScript &script;
+protected:
+    // These check for scripts for which a special case with a shorter encoding is defined.
+    // They are implemented separately from the CScript test, as these test for exact byte
+    // sequence correspondences, and are more strict. For example, IsToPubKey also verifies
+    // whether the public key is valid (as invalid ones cannot be represented in compressed
+    // form).
+    bool IsToKeyID(CKeyID &hash) const;
+    bool IsToScriptID(CScriptID &hash) const;
+    bool IsToPubKey(CPubKey &pubkey) const;
+
+    bool Compress(std::vector<unsigned char> &out) const;
+    unsigned int GetSpecialSize(unsigned int nSize) const;
+    bool Decompress(unsigned int nSize, const std::vector<unsigned char> &out);
+public:
+    CScriptCompressor(CScript &scriptIn) : script(scriptIn) { }
+
+    unsigned int GetSerializeSize(int nType, int nVersion) const {
+        std::vector<unsigned char> compr;
+        if (Compress(compr))
+            return compr.size();
+        unsigned int nSize = script.size() + nSpecialScripts;
+        return script.size() + VARINT(nSize).GetSerializeSize(nType, nVersion);
+    }
+
+    template<typename Stream>
+    void Serialize(Stream &s, int nType, int nVersion) const {
+        std::vector<unsigned char> compr;
+        if (Compress(compr)) {
+            s << CFlatData(compr);
+            return;
+        }
+        unsigned int nSize = script.size() + nSpecialScripts;
+        s << VARINT(nSize);
+        s << CFlatData(script);
+    }
+
+    template<typename Stream>
+    void Unserialize(Stream &s, int nType, int nVersion) {
+        unsigned int nSize = 0;
+        s >> VARINT(nSize);
+        if (nSize < nSpecialScripts) {
+            std::vector<unsigned char> vch(GetSpecialSize(nSize), 0x00);
+            s >> REF(CFlatData(vch));
+            Decompress(nSize, vch);
+            return;
+        }
+        nSize -= nSpecialScripts;
+        script.resize(nSize);
+        s >> REF(CFlatData(script));
+    }
+};
+
+#endif
diff --git a/src/scriptutils.cpp b/src/scriptutils.cpp
index cede11d6a7..cc38706d34 100644
--- a/src/scriptutils.cpp
+++ b/src/scriptutils.cpp
@@ -369,124 +369,3 @@ CScript CombineSignatures(CScript scriptPubKey, const CTransaction& txTo, unsign
 
     return CombineSignatures(scriptPubKey, txTo, nIn, txType, vSolutions, stack1, stack2);
 }
-
-bool CScriptCompressor::IsToKeyID(CKeyID &hash) const
-{
-    if (script.size() == 25 && script[0] == OP_DUP && script[1] == OP_HASH160
-                            && script[2] == 20 && script[23] == OP_EQUALVERIFY
-                            && script[24] == OP_CHECKSIG) {
-        memcpy(&hash, &script[3], 20);
-        return true;
-    }
-    return false;
-}
-
-bool CScriptCompressor::IsToScriptID(CScriptID &hash) const
-{
-    if (script.size() == 23 && script[0] == OP_HASH160 && script[1] == 20
-                            && script[22] == OP_EQUAL) {
-        memcpy(&hash, &script[2], 20);
-        return true;
-    }
-    return false;
-}
-
-bool CScriptCompressor::IsToPubKey(CPubKey &pubkey) const
-{
-    if (script.size() == 35 && script[0] == 33 && script[34] == OP_CHECKSIG
-                            && (script[1] == 0x02 || script[1] == 0x03)) {
-        pubkey.Set(&script[1], &script[34]);
-        return true;
-    }
-    if (script.size() == 67 && script[0] == 65 && script[66] == OP_CHECKSIG
-                            && script[1] == 0x04) {
-        pubkey.Set(&script[1], &script[66]);
-        return pubkey.IsFullyValid(); // if not fully valid, a case that would not be compressible
-    }
-    return false;
-}
-
-bool CScriptCompressor::Compress(std::vector<unsigned char> &out) const
-{
-    CKeyID keyID;
-    if (IsToKeyID(keyID)) {
-        out.resize(21);
-        out[0] = 0x00;
-        memcpy(&out[1], &keyID, 20);
-        return true;
-    }
-    CScriptID scriptID;
-    if (IsToScriptID(scriptID)) {
-        out.resize(21);
-        out[0] = 0x01;
-        memcpy(&out[1], &scriptID, 20);
-        return true;
-    }
-    CPubKey pubkey;
-    if (IsToPubKey(pubkey)) {
-        out.resize(33);
-        memcpy(&out[1], &pubkey[1], 32);
-        if (pubkey[0] == 0x02 || pubkey[0] == 0x03) {
-            out[0] = pubkey[0];
-            return true;
-        } else if (pubkey[0] == 0x04) {
-            out[0] = 0x04 | (pubkey[64] & 0x01);
-            return true;
-        }
-    }
-    return false;
-}
-
-unsigned int CScriptCompressor::GetSpecialSize(unsigned int nSize) const
-{
-    if (nSize == 0 || nSize == 1)
-        return 20;
-    if (nSize == 2 || nSize == 3 || nSize == 4 || nSize == 5)
-        return 32;
-    return 0;
-}
-
-bool CScriptCompressor::Decompress(unsigned int nSize, const std::vector<unsigned char> &in)
-{
-    switch(nSize) {
-    case 0x00:
-        script.resize(25);
-        script[0] = OP_DUP;
-        script[1] = OP_HASH160;
-        script[2] = 20;
-        memcpy(&script[3], &in[0], 20);
-        script[23] = OP_EQUALVERIFY;
-        script[24] = OP_CHECKSIG;
-        return true;
-    case 0x01:
-        script.resize(23);
-        script[0] = OP_HASH160;
-        script[1] = 20;
-        memcpy(&script[2], &in[0], 20);
-        script[22] = OP_EQUAL;
-        return true;
-    case 0x02:
-    case 0x03:
-        script.resize(35);
-        script[0] = 33;
-        script[1] = nSize;
-        memcpy(&script[2], &in[0], 32);
-        script[34] = OP_CHECKSIG;
-        return true;
-    case 0x04:
-    case 0x05:
-        unsigned char vch[33] = {};
-        vch[0] = nSize - 2;
-        memcpy(&vch[1], &in[0], 32);
-        CPubKey pubkey(&vch[0], &vch[33]);
-        if (!pubkey.Decompress())
-            return false;
-        assert(pubkey.size() == 65);
-        script.resize(67);
-        script[0] = 65;
-        memcpy(&script[1], pubkey.begin(), 65);
-        script[66] = OP_CHECKSIG;
-        return true;
-    }
-    return false;
-}
diff --git a/src/scriptutils.h b/src/scriptutils.h
index 7ea2c9e6a5..1c7408124e 100644
--- a/src/scriptutils.h
+++ b/src/scriptutils.h
@@ -31,79 +31,6 @@ enum isminetype
 /** used for bitflags of isminetype */
 typedef uint8_t isminefilter;
 
-/** Compact serializer for scripts.
- *
- *  It detects common cases and encodes them much more efficiently.
- *  3 special cases are defined:
- *  * Pay to pubkey hash (encoded as 21 bytes)
- *  * Pay to script hash (encoded as 21 bytes)
- *  * Pay to pubkey starting with 0x02, 0x03 or 0x04 (encoded as 33 bytes)
- *
- *  Other scripts up to 121 bytes require 1 byte + script length. Above
- *  that, scripts up to 16505 bytes require 2 bytes + script length.
- */
-class CScriptCompressor
-{
-private:
-    // make this static for now (there are only 6 special scripts defined)
-    // this can potentially be extended together with a new nVersion for
-    // transactions, in which case this value becomes dependent on nVersion
-    // and nHeight of the enclosing transaction.
-    static const unsigned int nSpecialScripts = 6;
-
-    CScript &script;
-protected:
-    // These check for scripts for which a special case with a shorter encoding is defined.
-    // They are implemented separately from the CScript test, as these test for exact byte
-    // sequence correspondences, and are more strict. For example, IsToPubKey also verifies
-    // whether the public key is valid (as invalid ones cannot be represented in compressed
-    // form).
-    bool IsToKeyID(CKeyID &hash) const;
-    bool IsToScriptID(CScriptID &hash) const;
-    bool IsToPubKey(CPubKey &pubkey) const;
-
-    bool Compress(std::vector<unsigned char> &out) const;
-    unsigned int GetSpecialSize(unsigned int nSize) const;
-    bool Decompress(unsigned int nSize, const std::vector<unsigned char> &out);
-public:
-    CScriptCompressor(CScript &scriptIn) : script(scriptIn) { }
-
-    unsigned int GetSerializeSize(int nType, int nVersion) const {
-        std::vector<unsigned char> compr;
-        if (Compress(compr))
-            return compr.size();
-        unsigned int nSize = script.size() + nSpecialScripts;
-        return script.size() + VARINT(nSize).GetSerializeSize(nType, nVersion);
-    }
-
-    template<typename Stream>
-    void Serialize(Stream &s, int nType, int nVersion) const {
-        std::vector<unsigned char> compr;
-        if (Compress(compr)) {
-            s << CFlatData(compr);
-            return;
-        }
-        unsigned int nSize = script.size() + nSpecialScripts;
-        s << VARINT(nSize);
-        s << CFlatData(script);
-    }
-
-    template<typename Stream>
-    void Unserialize(Stream &s, int nType, int nVersion) {
-        unsigned int nSize = 0;
-        s >> VARINT(nSize);
-        if (nSize < nSpecialScripts) {
-            std::vector<unsigned char> vch(GetSpecialSize(nSize), 0x00);
-            s >> REF(CFlatData(vch));
-            Decompress(nSize, vch);
-            return;
-        }
-        nSize -= nSpecialScripts;
-        script.resize(nSize);
-        s >> REF(CFlatData(script));
-    }
-};
-
 isminetype IsMine(const CKeyStore& keystore, const CScript& scriptPubKey);
 isminetype IsMine(const CKeyStore& keystore, const CTxDestination& dest);
 void ExtractAffectedKeys(const CKeyStore &keystore, const CScript& scriptPubKey, std::vector<CKeyID> &vKeys);