Merge pull request #5252

b9a36b1 Make comments in /src/script doxygen compatible (Michael Ford)

src/script/interpreter.cpp

@@ -41,10 +41,10 @@ bool CastToBool(const valtype& vch)
     return false;
 }
 
-//
-// Script is a stack machine (like Forth) that evaluates a predicate
-// returning a bool indicating valid or not.  There are no loops.
-//
+/**
+ * Script is a stack machine (like Forth) that evaluates a predicate
+ * returning a bool indicating valid or not.  There are no loops.
+ */
 #define stacktop(i)  (stack.at(stack.size()+(i)))
 #define altstacktop(i)  (altstack.at(altstack.size()+(i)))
 static inline void popstack(vector<valtype>& stack)
@@ -69,12 +69,16 @@ bool static IsCompressedOrUncompressedPubKey(const valtype &vchPubKey) {
     return true;
 }
 
+/**
+ * A canonical signature exists of: <30> <total len> <02> <len R> <R> <02> <len S> <S> <hashtype>
+ * Where R and S are not negative (their first byte has its highest bit not set), and not
+ * excessively padded (do not start with a 0 byte, unless an otherwise negative number follows,
+ * in which case a single 0 byte is necessary and even required).
+ * 
+ * See https://bitcointalk.org/index.php?topic=8392.msg127623#msg127623
+ */
 bool static IsDERSignature(const valtype &vchSig) {
-    // See https://bitcointalk.org/index.php?topic=8392.msg127623#msg127623
-    // A canonical signature exists of: <30> <total len> <02> <len R> <R> <02> <len S> <S> <hashtype>
-    // Where R and S are not negative (their first byte has its highest bit not set), and not
-    // excessively padded (do not start with a 0 byte, unless an otherwise negative number follows,
-    // in which case a single 0 byte is necessary and even required).
+
     if (vchSig.size() < 9)
         return error("Non-canonical signature: too short");
     if (vchSig.size() > 73)
@@ -862,17 +866,18 @@ bool EvalScript(vector<vector<unsigned char> >& stack, const CScript& script, un
 
 namespace {
 
-/** Wrapper that serializes like CTransaction, but with the modifications
+/**
+ * Wrapper that serializes like CTransaction, but with the modifications
  *  required for the signature hash done in-place
  */
 class CTransactionSignatureSerializer {
 private:
-    const CTransaction &txTo;  // reference to the spending transaction (the one being serialized)
-    const CScript &scriptCode; // output script being consumed
-    const unsigned int nIn;    // input index of txTo being signed
-    const bool fAnyoneCanPay;  // whether the hashtype has the SIGHASH_ANYONECANPAY flag set
-    const bool fHashSingle;    // whether the hashtype is SIGHASH_SINGLE
-    const bool fHashNone;      // whether the hashtype is SIGHASH_NONE
+    const CTransaction &txTo;  //! reference to the spending transaction (the one being serialized)
+    const CScript &scriptCode; //! output script being consumed
+    const unsigned int nIn;    //! input index of txTo being signed
+    const bool fAnyoneCanPay;  //! whether the hashtype has the SIGHASH_ANYONECANPAY flag set
+    const bool fHashSingle;    //! whether the hashtype is SIGHASH_SINGLE
+    const bool fHashNone;      //! whether the hashtype is SIGHASH_NONE
 
 public:
     CTransactionSignatureSerializer(const CTransaction &txToIn, const CScript &scriptCodeIn, unsigned int nInIn, int nHashTypeIn) :
@@ -951,7 +956,7 @@ public:
         ::WriteCompactSize(s, nOutputs);
         for (unsigned int nOutput = 0; nOutput < nOutputs; nOutput++)
              SerializeOutput(s, nOutput, nType, nVersion);
-        // Serialie nLockTime
+        // Serialize nLockTime
         ::Serialize(s, txTo.nLockTime, nType, nVersion);
     }
 };

src/script/script.h

@@ -179,12 +179,14 @@ public:
 
 class CScriptNum
 {
-// Numeric opcodes (OP_1ADD, etc) are restricted to operating on 4-byte integers.
-// The semantics are subtle, though: operands must be in the range [-2^31 +1...2^31 -1],
-// but results may overflow (and are valid as long as they are not used in a subsequent
-// numeric operation). CScriptNum enforces those semantics by storing results as
-// an int64 and allowing out-of-range values to be returned as a vector of bytes but
-// throwing an exception if arithmetic is done or the result is interpreted as an integer.
+/**
+ * Numeric opcodes (OP_1ADD, etc) are restricted to operating on 4-byte integers.
+ * The semantics are subtle, though: operands must be in the range [-2^31 +1...2^31 -1],
+ * but results may overflow (and are valid as long as they are not used in a subsequent
+ * numeric operation). CScriptNum enforces those semantics by storing results as
+ * an int64 and allowing out-of-range values to be returned as a vector of bytes but
+ * throwing an exception if arithmetic is done or the result is interpreted as an integer.
+ */
 public:
 
     explicit CScriptNum(const int64_t& n)
@@ -516,7 +518,7 @@ public:
         return true;
     }
 
-    // Encode/decode small integers:
+    /** Encode/decode small integers: */
     static int DecodeOP_N(opcodetype opcode)
     {
         if (opcode == OP_0)
@@ -560,25 +562,31 @@ public:
         return nFound;
     }
 
-    // Pre-version-0.6, Bitcoin always counted CHECKMULTISIGs
-    // as 20 sigops. With pay-to-script-hash, that changed:
-    // CHECKMULTISIGs serialized in scriptSigs are
-    // counted more accurately, assuming they are of the form
-    //  ... OP_N CHECKMULTISIG ...
+    /**
+     * Pre-version-0.6, Bitcoin always counted CHECKMULTISIGs
+     * as 20 sigops. With pay-to-script-hash, that changed:
+     * CHECKMULTISIGs serialized in scriptSigs are
+     * counted more accurately, assuming they are of the form
+     *  ... OP_N CHECKMULTISIG ...
+     */
     unsigned int GetSigOpCount(bool fAccurate) const;
 
-    // Accurately count sigOps, including sigOps in
-    // pay-to-script-hash transactions:
+    /**
+     * Accurately count sigOps, including sigOps in
+     * pay-to-script-hash transactions:
+     */
     unsigned int GetSigOpCount(const CScript& scriptSig) const;
 
     bool IsPayToScriptHash() const;
 
-    // Called by IsStandardTx and P2SH/BIP62 VerifyScript (which makes it consensus-critical).
+    /** Called by IsStandardTx and P2SH/BIP62 VerifyScript (which makes it consensus-critical). */
     bool IsPushOnly() const;
 
-    // Returns whether the script is guaranteed to fail at execution,
-    // regardless of the initial stack. This allows outputs to be pruned
-    // instantly when entering the UTXO set.
+    /**
+     * Returns whether the script is guaranteed to fail at execution,
+     * regardless of the initial stack. This allows outputs to be pruned
+     * instantly when entering the UTXO set.
+     */
     bool IsUnspendable() const
     {
         return (size() > 0 && *begin() == OP_RETURN);

src/script/sigcache.cpp

@@ -15,13 +15,15 @@
 
 namespace {
 
-// Valid signature cache, to avoid doing expensive ECDSA signature checking
-// twice for every transaction (once when accepted into memory pool, and
-// again when accepted into the block chain)
+/**
+ * Valid signature cache, to avoid doing expensive ECDSA signature checking
+ * twice for every transaction (once when accepted into memory pool, and
+ * again when accepted into the block chain)
+ */
 class CSignatureCache
 {
 private:
-     // sigdata_type is (signature hash, signature, public key):
+     //! sigdata_type is (signature hash, signature, public key):
     typedef boost::tuple<uint256, std::vector<unsigned char>, CPubKey> sigdata_type;
     std::set< sigdata_type> setValid;
     boost::shared_mutex cs_sigcache;

src/script/sign.cpp

@@ -46,12 +46,12 @@ bool SignN(const vector<valtype>& multisigdata, const CKeyStore& keystore, uint2
     return nSigned==nRequired;
 }
 
-//
-// Sign scriptPubKey with private keys stored in keystore, given transaction hash and hash type.
-// Signatures are returned in scriptSigRet (or returns false if scriptPubKey can't be signed),
-// unless whichTypeRet is TX_SCRIPTHASH, in which case scriptSigRet is the redemption script.
-// Returns false if scriptPubKey could not be completely satisfied.
-//
+/**
+ * Sign scriptPubKey with private keys stored in keystore, given transaction hash and hash type.
+ * Signatures are returned in scriptSigRet (or returns false if scriptPubKey can't be signed),
+ * unless whichTypeRet is TX_SCRIPTHASH, in which case scriptSigRet is the redemption script.
+ * Returns false if scriptPubKey could not be completely satisfied.
+ */
 bool Solver(const CKeyStore& keystore, const CScript& scriptPubKey, uint256 hash, int nHashType,
                   CScript& scriptSigRet, txnouttype& whichTypeRet)
 {

src/script/sign.h

@@ -17,8 +17,10 @@ struct CMutableTransaction;
 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.
+/**
+ * Given two sets of signatures for scriptPubKey, possibly with OP_0 placeholders,
+ * combine them intelligently and return the result.
+ */
 CScript CombineSignatures(const CScript& scriptPubKey, const CTransaction& txTo, unsigned int nIn, const CScript& scriptSig1, const CScript& scriptSig2);
 
 #endif // BITCOIN_SCRIPT_SIGN_H

src/script/standard.cpp

@@ -34,9 +34,9 @@ const char* GetTxnOutputType(txnouttype t)
     return NULL;
 }
 
-//
-// Return public keys or hashes from scriptPubKey, for 'standard' transaction types.
-//
+/**
+ * Return public keys or hashes from scriptPubKey, for 'standard' transaction types.
+ */
 bool Solver(const CScript& scriptPubKey, txnouttype& typeRet, vector<vector<unsigned char> >& vSolutionsRet)
 {
     // Templates

src/script/standard.h

@@ -25,27 +25,31 @@ public:
     CScriptID(const uint160& in) : uint160(in) {}
 };
 
-static const unsigned int MAX_OP_RETURN_RELAY = 40;      // bytes
+static const unsigned int MAX_OP_RETURN_RELAY = 40;      //! bytes
 extern unsigned nMaxDatacarrierBytes;
 
-// Mandatory script verification flags that all new blocks must comply with for
-// them to be valid. (but old blocks may not comply with) Currently just P2SH,
-// but in the future other flags may be added, such as a soft-fork to enforce
-// strict DER encoding.
-//
-// Failing one of these tests may trigger a DoS ban - see CheckInputs() for
-// details.
+/**
+ * Mandatory script verification flags that all new blocks must comply with for
+ * them to be valid. (but old blocks may not comply with) Currently just P2SH,
+ * but in the future other flags may be added, such as a soft-fork to enforce
+ * strict DER encoding.
+ * 
+ * Failing one of these tests may trigger a DoS ban - see CheckInputs() for
+ * details.
+ */
 static const unsigned int MANDATORY_SCRIPT_VERIFY_FLAGS = SCRIPT_VERIFY_P2SH;
 
-// Standard script verification flags that standard transactions will comply
-// with. However scripts violating these flags may still be present in valid
-// blocks and we must accept those blocks.
+/**
+ * Standard script verification flags that standard transactions will comply
+ * with. However scripts violating these flags may still be present in valid
+ * blocks and we must accept those blocks.
+ */
 static const unsigned int STANDARD_SCRIPT_VERIFY_FLAGS = MANDATORY_SCRIPT_VERIFY_FLAGS |
                                                          SCRIPT_VERIFY_STRICTENC |
                                                          SCRIPT_VERIFY_MINIMALDATA |
                                                          SCRIPT_VERIFY_NULLDUMMY;
 
-// For convenience, standard but not mandatory verify flags.
+/** For convenience, standard but not mandatory verify flags. */
 static const unsigned int STANDARD_NOT_MANDATORY_VERIFY_FLAGS = STANDARD_SCRIPT_VERIFY_FLAGS & ~MANDATORY_SCRIPT_VERIFY_FLAGS;
 
 enum txnouttype
@@ -65,7 +69,8 @@ public:
     friend bool operator<(const CNoDestination &a, const CNoDestination &b) { return true; }
 };
 
-/** A txout script template with a specific destination. It is either:
+/** 
+ * A txout script template with a specific destination. It is either:
  *  * CNoDestination: no destination set
  *  * CKeyID: TX_PUBKEYHASH destination
  *  * CScriptID: TX_SCRIPTHASH destination