replace asserts in RPC code with CHECK_NONFATAL and add linter

Author: adamjonas

src/rpc/blockchain.cpp

@@ -58,7 +58,7 @@ static CUpdatedBlock latestblock;
  */
 double GetDifficulty(const CBlockIndex* blockindex)
 {
-    assert(blockindex);
+    CHECK_NONFATAL(blockindex);
 
     int nShift = (blockindex->nBits >> 24) & 0xff;
     double dDiff =
@@ -957,7 +957,7 @@ static UniValue pruneblockchain(const JSONRPCRequest& request)
 
     PruneBlockFilesManual(height);
     const CBlockIndex* block = ::ChainActive().Tip();
-    assert(block);
+    CHECK_NONFATAL(block);
     while (block->pprev && (block->pprev->nStatus & BLOCK_HAVE_DATA)) {
         block = block->pprev;
     }
@@ -1252,7 +1252,7 @@ UniValue getblockchaininfo(const JSONRPCRequest& request)
     obj.pushKV("pruned",                fPruneMode);
     if (fPruneMode) {
         const CBlockIndex* block = tip;
-        assert(block);
+        CHECK_NONFATAL(block);
         while (block->pprev && (block->pprev->nStatus & BLOCK_HAVE_DATA)) {
             block = block->pprev;
         }
@@ -1598,7 +1598,7 @@ static UniValue getchaintxstats(const JSONRPCRequest& request)
         }
     }
 
-    assert(pindex != nullptr);
+    CHECK_NONFATAL(pindex != nullptr);
 
     if (request.params[0].isNull()) {
         blockcount = std::max(0, std::min(blockcount, pindex->nHeight - 1));
@@ -1771,7 +1771,7 @@ static UniValue getblockstats(const JSONRPCRequest& request)
         }
     }
 
-    assert(pindex != nullptr);
+    CHECK_NONFATAL(pindex != nullptr);
 
     std::set<std::string> stats;
     if (!request.params[1].isNull()) {
@@ -1871,7 +1871,7 @@ static UniValue getblockstats(const JSONRPCRequest& request)
             }
 
             CAmount txfee = tx_total_in - tx_total_out;
-            assert(MoneyRange(txfee));
+            CHECK_NONFATAL(MoneyRange(txfee));
             if (do_medianfee) {
                 fee_array.push_back(txfee);
             }
@@ -2008,7 +2008,7 @@ class CoinsViewScanReserver
     explicit CoinsViewScanReserver() : m_could_reserve(false) {}
 
     bool reserve() {
-        assert (!m_could_reserve);
+        CHECK_NONFATAL(!m_could_reserve);
         std::lock_guard<std::mutex> lock(g_utxosetscan);
         if (g_scan_in_progress) {
             return false;
@@ -2135,9 +2135,9 @@ UniValue scantxoutset(const JSONRPCRequest& request)
             LOCK(cs_main);
             ::ChainstateActive().ForceFlushStateToDisk();
             pcursor = std::unique_ptr<CCoinsViewCursor>(::ChainstateActive().CoinsDB().Cursor());
-            assert(pcursor);
+            CHECK_NONFATAL(pcursor);
             tip = ::ChainActive().Tip();
-            assert(tip);
+            CHECK_NONFATAL(tip);
         }
         bool res = FindScriptPubKey(g_scan_progress, g_should_abort_scan, count, pcursor.get(), needles, coins);
         result.pushKV("success", res);

src/rpc/mining.cpp

@@ -512,7 +512,7 @@ static UniValue getblocktemplate(const JSONRPCRequest& request)
         // Need to update only after we know CreateNewBlock succeeded
         pindexPrev = pindexPrevNew;
     }
-    assert(pindexPrev);
+    CHECK_NONFATAL(pindexPrev);
     CBlock* pblock = &pblocktemplate->block; // pointer for convenience
     const Consensus::Params& consensusParams = Params().GetConsensus();
 
@@ -554,7 +554,7 @@ static UniValue getblocktemplate(const JSONRPCRequest& request)
         entry.pushKV("fee", pblocktemplate->vTxFees[index_in_template]);
         int64_t nTxSigOps = pblocktemplate->vTxSigOpsCost[index_in_template];
         if (fPreSegWit) {
-            assert(nTxSigOps % WITNESS_SCALE_FACTOR == 0);
+            CHECK_NONFATAL(nTxSigOps % WITNESS_SCALE_FACTOR == 0);
             nTxSigOps /= WITNESS_SCALE_FACTOR;
         }
         entry.pushKV("sigops", nTxSigOps);
@@ -643,9 +643,9 @@ static UniValue getblocktemplate(const JSONRPCRequest& request)
     int64_t nSigOpLimit = MAX_BLOCK_SIGOPS_COST;
     int64_t nSizeLimit = MAX_BLOCK_SERIALIZED_SIZE;
     if (fPreSegWit) {
-        assert(nSigOpLimit % WITNESS_SCALE_FACTOR == 0);
+        CHECK_NONFATAL(nSigOpLimit % WITNESS_SCALE_FACTOR == 0);
         nSigOpLimit /= WITNESS_SCALE_FACTOR;
-        assert(nSizeLimit % WITNESS_SCALE_FACTOR == 0);
+        CHECK_NONFATAL(nSizeLimit % WITNESS_SCALE_FACTOR == 0);
         nSizeLimit /= WITNESS_SCALE_FACTOR;
     }
     result.pushKV("sigoplimit", nSigOpLimit);

src/rpc/util.cpp

@@ -428,7 +428,7 @@ RPCHelpMan::RPCHelpMan(std::string name, std::string description, std::vector<RP
     std::set<std::string> named_args;
     for (const auto& arg : m_args) {
         // Should have unique named arguments
-        assert(named_args.insert(arg.m_name).second);
+        CHECK_NONFATAL(named_args.insert(arg.m_name).second);
     }
 }
 
@@ -620,11 +620,11 @@ std::string RPCArg::ToStringObj(const bool oneline) const
     case Type::OBJ:
     case Type::OBJ_USER_KEYS:
         // Currently unused, so avoid writing dead code
-        assert(false);
+        CHECK_NONFATAL(false);
 
         // no default case, so the compiler can warn about missing cases
     }
-    assert(false);
+    CHECK_NONFATAL(false);
 }
 
 std::string RPCArg::ToString(const bool oneline) const
@@ -661,7 +661,7 @@ std::string RPCArg::ToString(const bool oneline) const
 
         // no default case, so the compiler can warn about missing cases
     }
-    assert(false);
+    CHECK_NONFATAL(false);
 }
 
 static std::pair<int64_t, int64_t> ParseRange(const UniValue& value)

src/wallet/rpcdump.cpp

@@ -162,7 +162,7 @@ UniValue importprivkey(const JSONRPCRequest& request)
         if (!key.IsValid()) throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Invalid private key encoding");
 
         CPubKey pubkey = key.GetPubKey();
-        assert(key.VerifyPubKey(pubkey));
+        CHECK_NONFATAL(key.VerifyPubKey(pubkey));
         CKeyID vchAddress = pubkey.GetID();
         {
             pwallet->MarkDirty();
@@ -642,7 +642,7 @@ UniValue importwallet(const JSONRPCRequest& request)
             std::string label = std::get<3>(key_tuple);
 
             CPubKey pubkey = key.GetPubKey();
-            assert(key.VerifyPubKey(pubkey));
+            CHECK_NONFATAL(key.VerifyPubKey(pubkey));
             CKeyID keyid = pubkey.GetID();
 
             pwallet->WalletLogPrintf("Importing %s...\n", EncodeDestination(PKHash(keyid)));
@@ -915,7 +915,7 @@ static std::string RecurseImportData(const CScript& script, ImportData& import_d
     case TX_SCRIPTHASH: {
         if (script_ctx == ScriptContext::P2SH) throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Trying to nest P2SH inside another P2SH");
         if (script_ctx == ScriptContext::WITNESS_V0) throw JSONRPCError(RPC_INVALID_ADDRESS_OR_KEY, "Trying to nest P2SH inside a P2WSH");
-        assert(script_ctx == ScriptContext::TOP);
+        CHECK_NONFATAL(script_ctx == ScriptContext::TOP);
         CScriptID id = CScriptID(uint160(solverdata[0]));
         auto subscript = std::move(import_data.redeemscript); // Remove redeemscript from import_data to check for superfluous script later.
         if (!subscript) return "missing redeemscript";

src/wallet/rpcwallet.cpp

@@ -136,7 +136,7 @@ static void WalletTxToJSON(interfaces::Chain& chain, interfaces::Chain::Lock& lo
         entry.pushKV("blockindex", wtx.m_confirm.nIndex);
         int64_t block_time;
         bool found_block = chain.findBlock(wtx.m_confirm.hashBlock, nullptr /* block */, &block_time);
-        assert(found_block);
+        CHECK_NONFATAL(found_block);
         entry.pushKV("blocktime", block_time);
     } else {
         entry.pushKV("trusted", wtx.IsTrusted(locked_chain));
@@ -2943,7 +2943,7 @@ static UniValue listunspent(const JSONRPCRequest& request)
                     CTxDestination witness_destination;
                     if (redeemScript.IsPayToWitnessScriptHash()) {
                         bool extracted = ExtractDestination(redeemScript, witness_destination);
-                        assert(extracted);
+                        CHECK_NONFATAL(extracted);
                         // Also return the witness script
                         const WitnessV0ScriptHash& whash = boost::get<WitnessV0ScriptHash>(witness_destination);
                         CScriptID id;
@@ -3833,7 +3833,7 @@ static UniValue getaddressesbylabel(const JSONRPCRequest& request)
             // address strings, but build a separate set as a precaution just in
             // case it does.
             bool unique = addresses.emplace(address).second;
-            assert(unique);
+            CHECK_NONFATAL(unique);
             // UniValue::pushKV checks if the key exists in O(N)
             // and since duplicate addresses are unexpected (checked with
             // std::set in O(log(N))), UniValue::__pushKV is used instead,

test/lint/lint-assertions.sh

@@ -20,4 +20,15 @@ if [[ ${OUTPUT} != "" ]]; then
     EXIT_CODE=1
 fi
 
+# Macro CHECK_NONFATAL(condition) should be used instead of assert for RPC code, where it
+# is undesirable to crash the whole program. See: src/util/check.h
+# src/rpc/server.cpp is excluded from this check since it's mostly meta-code.
+OUTPUT=$(git grep -nE 'assert *\(.*\);' -- "src/rpc/" "src/wallet/rpc*" ":(exclude)src/rpc/server.cpp")
+if [[ ${OUTPUT} != "" ]]; then
+    echo "CHECK_NONFATAL(condition) should be used instead of assert for RPC code."
+    echo
+    echo "${OUTPUT}"
+    EXIT_CODE=1
+fi
+
 exit ${EXIT_CODE}