Merge #21222: log: Clarify log message when file does not exist

faf48f20f1 log: Clarify log message when file does not exist (MarcoFalke)

Pull request description:

  Shorter and broader alternative to #21181

  Rendered diff:

  ```diff
  @@ -1,4 +1,4 @@
  -Bitcoin Core version v21.99.0-db656db2ed5a (release build)
  +Bitcoin Core version v21.99.0-faf48f20f196 (release build)
   Qt 5.15.2 (dynamic), plugin=wayland (dynamic)
   No static plugins.
   Style: adwaita / Adwaita::Style
  @@ -24,8 +24,8 @@ scheduler thread start
   Using wallet directory /tmp/test_001/regtest/wallets
   init message: Verifying wallet(s)...
   init message: Loading banlist...
  -ERROR: DeserializeFileDB: Failed to open file /tmp/test_001/regtest/banlist.dat
  -Invalid or missing banlist.dat; recreating
  +Missing or invalid file /tmp/test_001/regtest/banlist.dat
  +Recreating banlist.dat
   SetNetworkActive: true
   Failed to read fee estimates from /tmp/test_001/regtest/fee_estimates.dat. Continue anyway.
   Using /16 prefix for IP bucketing
  @@ -63,9 +63,9 @@ Bound to [::]:18444
   Bound to 0.0.0.0:18444
   Bound to 127.0.0.1:18445
   init message: Loading P2P addresses...
  -ERROR: DeserializeFileDB: Failed to open file /tmp/test_001/regtest/peers.dat
  -Invalid or missing peers.dat; recreating
  -ERROR: DeserializeFileDB: Failed to open file /tmp/test_001/regtest/anchors.dat
  +Missing or invalid file /tmp/test_001/regtest/peers.dat
  +Recreating peers.dat
  +Missing or invalid file /tmp/test_001/regtest/anchors.dat
   0 block-relay-only anchors will be tried for connections.
   init message: Starting network threads...
   net thread start

ACKs for top commit:
  jnewbery:
    utACK faf48f20f1
  amitiuttarwar:
    utACK faf48f20f1, 👍 for consistency. also checked where we create / load other `.dat` files, looks good to me.
  practicalswift:
    cr ACK faf48f20f1

Tree-SHA512: 697a728ef2b9f203363ac00b03eaf23ddf80bee043ecd3719265a0d884e8cfe88cd39afe946c86ab849edd1c836f05ec51125f052bdc14fe184b84447567756f

src/addrdb.cpp

@@ -109,15 +109,15 @@ template <typename Data>
 bool DeserializeFileDB(const fs::path& path, Data& data)
 {
     // open input file, and associate with CAutoFile
-    FILE *file = fsbridge::fopen(path, "rb");
+    FILE* file = fsbridge::fopen(path, "rb");
     CAutoFile filein(file, SER_DISK, CLIENT_VERSION);
-    if (filein.IsNull())
-        return error("%s: Failed to open file %s", __func__, path.string());
-
+    if (filein.IsNull()) {
+        LogPrintf("Missing or invalid file %s\n", path.string());
+        return false;
+    }
     return DeserializeDB(filein, data);
 }
-
-}
+} // namespace
 
 CBanDB::CBanDB(fs::path ban_list_path) : m_ban_list_path(std::move(ban_list_path))
 {

src/banman.cpp

@@ -28,7 +28,7 @@ BanMan::BanMan(fs::path ban_file, CClientUIInterface* client_interface, int64_t
         LogPrint(BCLog::NET, "Loaded %d banned node ips/subnets from banlist.dat  %dms\n",
             m_banned.size(), GetTimeMillis() - n_start);
     } else {
-        LogPrintf("Invalid or missing banlist.dat; recreating\n");
+        LogPrintf("Recreating banlist.dat\n");
         SetBannedSetDirty(true); // force write
         DumpBanlist();
     }

src/net.cpp

@@ -2389,7 +2389,7 @@ bool CConnman::Start(CScheduler& scheduler, const Options& connOptions)
             LogPrintf("Loaded %i addresses from peers.dat  %dms\n", addrman.size(), GetTimeMillis() - nStart);
         else {
             addrman.Clear(); // Addrman can be in an inconsistent state after failure, reset it
-            LogPrintf("Invalid or missing peers.dat; recreating\n");
+            LogPrintf("Recreating peers.dat\n");
             DumpAddresses();
         }
     }