1 files changed, 37 insertions, 4 deletions
diff --git a/src/script/sign.h b/src/script/sign.h
index e197d5fab3..0c4cf61e5e 100644
--- a/src/script/sign.h
+++ b/src/script/sign.h
@@ -8,19 +8,52 @@
 
 #include "script/interpreter.h"
 
+class CKeyID;
 class CKeyStore;
 class CScript;
 class CTransaction;
 
 struct CMutableTransaction;
 
+/** Virtual base class for signature creators. */
+class BaseSignatureCreator {
+protected:
+    const CKeyStore* keystore;
+
+public:
+    BaseSignatureCreator(const CKeyStore* keystoreIn) : keystore(keystoreIn) {}
+    const CKeyStore& KeyStore() const { return *keystore; };
+    virtual ~BaseSignatureCreator() {}
+    virtual const BaseSignatureChecker& Checker() const =0;
+
+    /** Create a singular (non-script) signature. */
+    virtual bool CreateSig(std::vector<unsigned char>& vchSig, const CKeyID& keyid, const CScript& scriptCode) const =0;
+};
+
+/** A signature creator for transactions. */
+class TransactionSignatureCreator : public BaseSignatureCreator {
+    const CTransaction* txTo;
+    unsigned int nIn;
+    int nHashType;
+    const TransactionSignatureChecker checker;
+
+public:
+    TransactionSignatureCreator(const CKeyStore* keystoreIn, const CTransaction* txToIn, unsigned int nInIn, int nHashTypeIn=SIGHASH_ALL);
+    const BaseSignatureChecker& Checker() const { return checker; }
+    bool CreateSig(std::vector<unsigned char>& vchSig, const CKeyID& keyid, const CScript& scriptCode) const;
+};
+
+/** Produce a script signature using a generic signature creator. */
+bool ProduceSignature(const BaseSignatureCreator& creator, const CScript& scriptPubKey, CScript& scriptSig);
+
+/** Produce a script signature for a transaction. */
 bool SignSignature(const CKeyStore& keystore, const CScript& fromPubKey, CMutableTransaction& txTo, unsigned int nIn, int nHashType=SIGHASH_ALL);
 bool SignSignature(const CKeyStore& keystore, const CTransaction& txFrom, CMutableTransaction& txTo, unsigned int nIn, int nHashType=SIGHASH_ALL);
 
-/**
- * Given two sets of signatures for scriptPubKey, possibly with OP_0 placeholders,
- * combine them intelligently and return the result.
- */
+/** Combine two script signatures using a generic signature checker, intelligently, possibly with OP_0 placeholders. */
+CScript CombineSignatures(const CScript& scriptPubKey, const BaseSignatureChecker& checker, const CScript& scriptSig1, const CScript& scriptSig2);
+
+/** Combine two script signatures on transactions. */
 CScript CombineSignatures(const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn, const CScript& scriptSig1, const CScript& scriptSig2);
 
 #endif // BITCOIN_SCRIPT_SIGN_H