Merge bitcoin/bitcoin#24464: logging: Add severity level to logs

e11cdc930375eaec8d737e116138b2f2018c099f  logging: Add log severity level to net.cpp (klementtan)
a8290649a6578df120a71c9493acdf071e010d96 logging: Add severity level to logs. (klementtan)

Pull request description:

  **Overview**: This PR introduces a new macro, `LogPrintLevel`, that allows developers to add logs with the severity level. Additionally, it will also print the log category if it is specified.

  Sample log:
  ```
  2022-03-04T16:41:15Z [opencon] [net:debug] trying connection XX.XX.XXX.XXX:YYYYY lastseen=2.7hrs
  ```

  **Motivation**: This feature was suggested in #20576 and I believe that it will bring the following benefits:
  * Allow for easier filtering of logs in `debug.log`
  * Can be extended to allow users to select the minimum level of logs they would like to view (not in the scope of this PR)

  **Details**:
  * New log format. `... [category:level]...`. ie:
    * Do not print category if `category == NONE`
    * Do not print level if `level == NONE`
    * If `category == NONE` and `level == NONE`, do not print any fields (current behaviour)
  * Previous logging functions:
    * `LogPrintf`:  no changes in log as it calls `LogPrintf_` with `category = NONE` and `level = NONE`
    * `LogPrint`: prints additional `[category]` field as it calls `LogPrintf_` with `category = category` and `level = NONE`
  * `net.cpp`: As a proof of concept, updated logs with obvious severity (ie prefixed with `Warning/Error:..`) to use the new logging with severity.

  **Testing**:
  * Compiling and running `bitcoind` with this PR should instantly display logs with the category name (ie `net/tor/...`)
  * Grepping for `net:debug` in `debug.log` should display the updated logs with severity level:
    <details>
    <summary>Code</summary>

    ```
    $ grep "net:debug" debug.log

    2022-03-04T16:41:15Z [opencon] [net:debug] trying connection XXX:YYY lastseen=2.7hrs
    2022-03-04T16:41:16Z [opencon] [net:debug] trying connection XXX:YYY lastseen=16.9hrs
    2022-03-04T16:41:17Z [opencon] [net:debug] trying connection XXX:YYY lastseen=93.2hrs
    2022-03-04T16:41:18Z [opencon] [net:debug] trying connection XXX:YYY lastseen=2.7hrs
    ```
    </details>

ACKs for top commit:
  laanwj:
    Code review and lightly tested ACK e11cdc930375eaec8d737e116138b2f2018c099f

Tree-SHA512: 89a8c86667ccc0688e5acfdbd399aac1f5bec9f978a160e40b0210b0d9b8fdc338479583fc5bd2e2bc785821363f174f578d52136d228e8f638a20abbf0a568f

1 files changed, 12 insertions, 12 deletions

diff --git a/src/net.cpp b/src/net.cpp
index 676037a357..918249c813 100644
--- a/src/net.cpp
+++ b/src/net.cpp
@@ -430,7 +430,7 @@ static CAddress GetBindAddress(SOCKET sock)
         if (!getsockname(sock, (struct sockaddr*)&sockaddr_bind, &sockaddr_bind_len)) {
             addr_bind.SetSockAddr((const struct sockaddr*)&sockaddr_bind);
         } else {
-            LogPrint(BCLog::NET, "Warning: getsockname failed\n");
+            LogPrintLevel(BCLog::Level::Warning, BCLog::NET, "getsockname failed\n");
         }
     }
     return addr_bind;
@@ -454,9 +454,9 @@ CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCo
     }
 
     /// debug print
-    LogPrint(BCLog::NET, "trying connection %s lastseen=%.1fhrs\n",
-        pszDest ? pszDest : addrConnect.ToString(),
-        pszDest ? 0.0 : (double)(GetAdjustedTime() - addrConnect.nTime)/3600.0);
+    LogPrintLevel(BCLog::Level::Debug, BCLog::NET, "trying connection %s lastseen=%.1fhrs\n",
+                  pszDest ? pszDest : addrConnect.ToString(),
+                  pszDest ? 0.0 : (double)(GetAdjustedTime() - addrConnect.nTime) / 3600.0);
 
     // Resolve
     const uint16_t default_port{pszDest != nullptr ? Params().GetDefaultPort(pszDest) :
@@ -1140,7 +1140,7 @@ void CConnman::AcceptConnection(const ListenSocket& hListenSocket) {
     }
 
     if (!addr.SetSockAddr((const struct sockaddr*)&sockaddr)) {
-        LogPrintf("Warning: Unknown socket family\n");
+        LogPrintLevel(BCLog::Level::Warning, BCLog::NET, "Unknown socket family\n");
     } else {
         addr = CAddress{MaybeFlipIPv6toCJDNS(addr), NODE_NONE};
     }
@@ -2397,15 +2397,15 @@ bool CConnman::BindListenPort(const CService& addrBind, bilingual_str& strError,
     socklen_t len = sizeof(sockaddr);
     if (!addrBind.GetSockAddr((struct sockaddr*)&sockaddr, &len))
     {
-        strError = strprintf(Untranslated("Error: Bind address family for %s not supported"), addrBind.ToString());
-        LogPrintf("%s\n", strError.original);
+        strError = strprintf(Untranslated("Bind address family for %s not supported"), addrBind.ToString());
+        LogPrintLevel(BCLog::Level::Error, BCLog::NET, "%s\n", strError.original);
         return false;
     }
 
     std::unique_ptr<Sock> sock = CreateSock(addrBind);
     if (!sock) {
-        strError = strprintf(Untranslated("Error: Couldn't open socket for incoming connections (socket returned error %s)"), NetworkErrorString(WSAGetLastError()));
-        LogPrintf("%s\n", strError.original);
+        strError = strprintf(Untranslated("Couldn't open socket for incoming connections (socket returned error %s)"), NetworkErrorString(WSAGetLastError()));
+        LogPrintLevel(BCLog::Level::Error, BCLog::NET, "%s\n", strError.original);
         return false;
     }
 
@@ -2441,7 +2441,7 @@ bool CConnman::BindListenPort(const CService& addrBind, bilingual_str& strError,
             strError = strprintf(_("Unable to bind to %s on this computer. %s is probably already running."), addrBind.ToString(), PACKAGE_NAME);
         else
             strError = strprintf(_("Unable to bind to %s on this computer (bind returned error %s)"), addrBind.ToString(), NetworkErrorString(nErr));
-        LogPrintf("%s\n", strError.original);
+        LogPrintLevel(BCLog::Level::Error, BCLog::NET, "%s\n", strError.original);
         return false;
     }
     LogPrintf("Bound to %s\n", addrBind.ToString());
@@ -2449,8 +2449,8 @@ bool CConnman::BindListenPort(const CService& addrBind, bilingual_str& strError,
     // Listen for incoming connections
     if (listen(sock->Get(), SOMAXCONN) == SOCKET_ERROR)
     {
-        strError = strprintf(_("Error: Listening for incoming connections failed (listen returned error %s)"), NetworkErrorString(WSAGetLastError()));
-        LogPrintf("%s\n", strError.original);
+        strError = strprintf(_("Listening for incoming connections failed (listen returned error %s)"), NetworkErrorString(WSAGetLastError()));
+        LogPrintLevel(BCLog::Level::Error, BCLog::NET, "%s\n", strError.original);
         return false;
     }