Merge #18541: rpc: Make verifychain default values static, not depend on global args

fad691c rpc: Make verifychain default values static, not depend on global args (MarcoFalke)

Pull request description:

  This fixes several issues:

  * The documentation is not compile-time static and depends on run-time arguments, making it impossible to host it on a static resource like a website or pdf. See also a similar change in the wallet rpc code: #18499
  * The same call (relying on default values) will run different code on different machines, depending on the command line args that were used to start the server. This might lead to hard-to-debug-remote issues.

  This is a small behaviour change, and I will add release notes.

ACKs for top commit:
  theStack:
    ACK bitcoin/bitcoin@fad691c
  promag:
    Code review ACK fad691c.

Tree-SHA512: 1c7a253ff0ec13a973b10d3777b71c70954ded5805b65a3ab06317327014de4cd0601d71d30c6ce89a581722c150cb5567acc1bd3e0c789cb51bab6ef0dcfc4a

Author: MarcoFalke

src/rpc/blockchain.cpp

@@ -1078,13 +1078,11 @@ UniValue gettxout(const JSONRPCRequest& request)
 
 static UniValue verifychain(const JSONRPCRequest& request)
 {
-    int nCheckLevel = gArgs.GetArg("-checklevel", DEFAULT_CHECKLEVEL);
-    int nCheckDepth = gArgs.GetArg("-checkblocks", DEFAULT_CHECKBLOCKS);
             RPCHelpMan{"verifychain",
                 "\nVerifies blockchain database.\n",
                 {
-                    {"checklevel", RPCArg::Type::NUM, /* default */ strprintf("%d, range=0-4", nCheckLevel), "How thorough the block verification is."},
-                    {"nblocks", RPCArg::Type::NUM, /* default */ strprintf("%d, 0=all", nCheckDepth), "The number of blocks to check."},
+                    {"checklevel", RPCArg::Type::NUM, /* default */ strprintf("%d, range=0-4", DEFAULT_CHECKLEVEL), "How thorough the block verification is."},
+                    {"nblocks", RPCArg::Type::NUM, /* default */ strprintf("%d, 0=all", DEFAULT_CHECKBLOCKS), "The number of blocks to check."},
                 },
                 RPCResult{
                     RPCResult::Type::BOOL, "", "Verified or not"},
@@ -1094,15 +1092,12 @@ static UniValue verifychain(const JSONRPCRequest& request)
                 },
             }.Check(request);
 
-    LOCK(cs_main);
+    const int check_level(request.params[0].isNull() ? DEFAULT_CHECKLEVEL : request.params[0].get_int());
+    const int check_depth{request.params[1].isNull() ? DEFAULT_CHECKBLOCKS : request.params[1].get_int()};
 
-    if (!request.params[0].isNull())
-        nCheckLevel = request.params[0].get_int();
-    if (!request.params[1].isNull())
-        nCheckDepth = request.params[1].get_int();
+    LOCK(cs_main);
 
-    return CVerifyDB().VerifyDB(
-        Params(), &::ChainstateActive().CoinsTip(), nCheckLevel, nCheckDepth);
+    return CVerifyDB().VerifyDB(Params(), &::ChainstateActive().CoinsTip(), check_level, check_depth);
 }
 
 static void BuriedForkDescPushBack(UniValue& softforks, const std::string &name, int height) EXCLUSIVE_LOCKS_REQUIRED(cs_main)