Return the script type from Solver

Because false is synonymous with TX_NONSTANDARD, this conveys the same
information and makes the handling explicitly based on script type,
simplifying each call site.

Prior to this change it was common for the return value to be ignored,
or for the return value and TX_NONSTANDARD to be redundantly handled.

1 files changed, 10 insertions, 13 deletions

diff --git a/src/policy/policy.cpp b/src/policy/policy.cpp
index 3a592e40d3..f1ba09d4d2 100644
--- a/src/policy/policy.cpp
+++ b/src/policy/policy.cpp
@@ -57,11 +57,11 @@ bool IsDust(const CTxOut& txout, const CFeeRate& dustRelayFeeIn)
 bool IsStandard(const CScript& scriptPubKey, txnouttype& whichType)
 {
     std::vector<std::vector<unsigned char> > vSolutions;
-    if (!Solver(scriptPubKey, whichType, vSolutions))
-        return false;
+    whichType = Solver(scriptPubKey, vSolutions);
 
-    if (whichType == TX_MULTISIG)
-    {
+    if (whichType == TX_NONSTANDARD || whichType == TX_WITNESS_UNKNOWN) {
+        return false;
+    } else if (whichType == TX_MULTISIG) {
         unsigned char m = vSolutions.front()[0];
         unsigned char n = vSolutions.back()[0];
         // Support up to x-of-3 multisig txns as standard
@@ -70,10 +70,11 @@ bool IsStandard(const CScript& scriptPubKey, txnouttype& whichType)
         if (m < 1 || m > n)
             return false;
     } else if (whichType == TX_NULL_DATA &&
-               (!fAcceptDatacarrier || scriptPubKey.size() > nMaxDatacarrierBytes))
+               (!fAcceptDatacarrier || scriptPubKey.size() > nMaxDatacarrierBytes)) {
           return false;
+    }
 
-    return whichType != TX_NONSTANDARD && whichType != TX_WITNESS_UNKNOWN;
+    return true;
 }
 
 bool IsStandardTx(const CTransaction& tx, std::string& reason)
@@ -166,14 +167,10 @@ bool AreInputsStandard(const CTransaction& tx, const CCoinsViewCache& mapInputs)
         const CTxOut& prev = mapInputs.AccessCoin(tx.vin[i].prevout).out;
 
         std::vector<std::vector<unsigned char> > vSolutions;
-        txnouttype whichType;
-        // get the scriptPubKey corresponding to this input:
-        const CScript& prevScript = prev.scriptPubKey;
-        if (!Solver(prevScript, whichType, vSolutions))
+        txnouttype whichType = Solver(prev.scriptPubKey, vSolutions);
+        if (whichType == TX_NONSTANDARD) {
             return false;
-
-        if (whichType == TX_SCRIPTHASH)
-        {
+        } else if (whichType == TX_SCRIPTHASH) {
             std::vector<std::vector<unsigned char> > stack;
             // convert the scriptSig into a stack, so we can inspect the redeemScript
             if (!EvalScript(stack, tx.vin[i].scriptSig, SCRIPT_VERIFY_NONE, BaseSignatureChecker(), SigVersion::BASE))