Switch away from exceptions in refactored tx code

After refactoring general-purpose PSBT and transaction code out of RPC code,
for use in the GUI, it's no longer appropriate to throw exceptions. Instead we
now return bools for success, and take an output parameter for an error object.
We still use JSONRPCError() for the error objects, since only RPC callers
actually care about the error codes.

3 files changed, 38 insertions, 1 deletions

diff --git a/src/rpc/rawtransaction.cpp b/src/rpc/rawtransaction.cpp
index 03e38739a1..bc836614ae 100644
--- a/src/rpc/rawtransaction.cpp
+++ b/src/rpc/rawtransaction.cpp
@@ -1050,7 +1050,14 @@ static UniValue sendrawtransaction(const JSONRPCRequest& request)
 
     bool allowhighfees = false;
     if (!request.params[1].isNull()) allowhighfees = request.params[1].get_bool();
-    return BroadcastTransaction(tx, allowhighfees).GetHex();
+    uint256 txid;
+    TransactionError err;
+    std::string err_string;
+    if (!BroadcastTransaction(tx, txid, err, err_string, allowhighfees)) {
+        throw JSONRPCTransactionError(err, err_string);
+    }
+
+    return txid.GetHex();
 }
 
 static UniValue testmempoolaccept(const JSONRPCRequest& request)
diff --git a/src/rpc/util.cpp b/src/rpc/util.cpp
index aa5076cd8e..9e825ac12a 100644
--- a/src/rpc/util.cpp
+++ b/src/rpc/util.cpp
@@ -141,6 +141,32 @@ unsigned int ParseConfirmTarget(const UniValue& value)
     return (unsigned int)target;
 }
 
+RPCErrorCode RPCErrorFromTransactionError(TransactionError terr)
+{
+    switch (terr) {
+        case TransactionError::MEMPOOL_REJECTED:
+            return RPC_TRANSACTION_REJECTED;
+        case TransactionError::ALREADY_IN_CHAIN:
+            return RPC_TRANSACTION_ALREADY_IN_CHAIN;
+        case TransactionError::P2P_DISABLED:
+            return RPC_CLIENT_P2P_DISABLED;
+        case TransactionError::INVALID_PSBT:
+        case TransactionError::SIGHASH_MISMATCH:
+            return RPC_DESERIALIZATION_ERROR;
+        default: break;
+    }
+    return RPC_TRANSACTION_ERROR;
+}
+
+UniValue JSONRPCTransactionError(TransactionError terr, const std::string& err_string)
+{
+    if (err_string.length() > 0) {
+        return JSONRPCError(RPCErrorFromTransactionError(terr), err_string);
+    } else {
+        return JSONRPCError(RPCErrorFromTransactionError(terr), TransactionErrorString(terr));
+    }
+}
+
 struct Section {
     Section(const std::string& left, const std::string& right)
         : m_left{left}, m_right{right} {}
diff --git a/src/rpc/util.h b/src/rpc/util.h
index d34c9cfdbb..33fca79029 100644
--- a/src/rpc/util.h
+++ b/src/rpc/util.h
@@ -5,6 +5,7 @@
 #ifndef BITCOIN_RPC_UTIL_H
 #define BITCOIN_RPC_UTIL_H
 
+#include <node/transaction.h>
 #include <pubkey.h>
 #include <script/standard.h>
 #include <univalue.h>
@@ -31,6 +32,9 @@ UniValue DescribeAddress(const CTxDestination& dest);
 //! Parse a confirm target option and raise an RPC error if it is invalid.
 unsigned int ParseConfirmTarget(const UniValue& value);
 
+RPCErrorCode RPCErrorFromTransactionError(TransactionError terr);
+UniValue JSONRPCTransactionError(TransactionError terr, const std::string& err_string = "");
+
 struct RPCArg {
     enum class Type {
         OBJ,