FillPSBT: report number of inputs signed (or would sign)

In FillPSBT, optionally report the number of inputs we successfully
signed, as an out parameter. If "sign" is false, instead report the
number of inputs for which GetSigningProvider does not return nullptr.
(This is a potentially overbroad estimate of inputs we could sign.)

1 files changed, 10 insertions, 2 deletions

diff --git a/src/wallet/wallet.cpp b/src/wallet/wallet.cpp
index 4037e23b6..e02d17211 100644
--- a/src/wallet/wallet.cpp
+++ b/src/wallet/wallet.cpp
@@ -2471,8 +2471,11 @@ bool CWallet::SignTransaction(CMutableTransaction& tx, const std::map<COutPoint,
     return false;
 }
 
-TransactionError CWallet::FillPSBT(PartiallySignedTransaction& psbtx, bool& complete, int sighash_type, bool sign, bool bip32derivs) const
+TransactionError CWallet::FillPSBT(PartiallySignedTransaction& psbtx, bool& complete, int sighash_type, bool sign, bool bip32derivs, size_t * n_signed) const
 {
+    if (n_signed) {
+        *n_signed = 0;
+    }
     LOCK(cs_wallet);
     // Get all of the previous transactions
     for (unsigned int i = 0; i < psbtx.tx->vin.size(); ++i) {
@@ -2503,10 +2506,15 @@ TransactionError CWallet::FillPSBT(PartiallySignedTransaction& psbtx, bool& comp
 
     // Fill in information from ScriptPubKeyMans
     for (ScriptPubKeyMan* spk_man : GetAllScriptPubKeyMans()) {
-        TransactionError res = spk_man->FillPSBT(psbtx, sighash_type, sign, bip32derivs);
+        int n_signed_this_spkm = 0;
+        TransactionError res = spk_man->FillPSBT(psbtx, sighash_type, sign, bip32derivs, &n_signed_this_spkm);
         if (res != TransactionError::OK) {
             return res;
         }
+
+        if (n_signed) {
+            (*n_signed) += n_signed_this_spkm;
+        }
     }
 
     // Complete if every input is now signed