Remove `-sysperms` option

This change effectively reverts commits from
https://github.com/bitcoin/bitcoin/pull/4286.

Users, who rely on non-default access permissions, should use `chmod`
command.

doc/init.md

@@ -70,7 +70,7 @@ NOTE: When using the systemd .service file, the creation of the aforementioned
 directories and the setting of their permissions is automatically handled by
 systemd. Directories are given a permission of 710, giving the bitcoin group
 access to files under it _if_ the files themselves give permission to the
-bitcoin group to do so (e.g. when `-sysperms` is specified). This does not allow
+bitcoin group to do so. This does not allow
 for the listing of files under the directory.
 
 NOTE: It is not currently possible to override `datadir` in

src/i2p.cpp

@@ -336,7 +336,7 @@ void Session::GenerateAndSavePrivateKey(const Sock& sock)
 {
     DestGenerate(sock);
 
-    // umask is set to 077 in init.cpp, which is ok (unless -sysperms is given)
+    // umask is set to 077 in init.cpp, which is ok.
     if (!WriteBinaryFile(m_private_key_file,
                          std::string(m_private_key.begin(), m_private_key.end()))) {
         throw std::runtime_error(

src/init.cpp

@@ -458,11 +458,6 @@ void SetupServerArgs(ArgsManager& argsman)
 #if HAVE_SYSTEM
     argsman.AddArg("-startupnotify=<cmd>", "Execute command on startup.", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-shutdownnotify=<cmd>", "Execute command immediately before beginning shutdown. The need for shutdown may be urgent, so be careful not to delay it long (if the command doesn't require interaction with the server, consider having it fork into the background).", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
-#endif
-#ifndef WIN32
-    argsman.AddArg("-sysperms", "Create new files with system default permissions, instead of umask 077 (only effective with disabled wallet functionality)", ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
-#else
-    hidden_args.emplace_back("-sysperms");
 #endif
     argsman.AddArg("-txindex", strprintf("Maintain a full transaction index, used by the getrawtransaction rpc call (default: %u)", DEFAULT_TXINDEX), ArgsManager::ALLOW_ANY, OptionsCategory::OPTIONS);
     argsman.AddArg("-blockfilterindex=<type>",
@@ -821,9 +816,7 @@ bool AppInitBasicSetup(const ArgsManager& args)
     }
 
 #ifndef WIN32
-    if (!args.GetBoolArg("-sysperms", false)) {
-        umask(077);
-    }
+    umask(077);
 
     // Clean shutdown on SIGTERM
     registerSignalHandler(SIGTERM, HandleSIGTERM);

src/rpc/request.cpp

@@ -86,7 +86,7 @@ bool GenerateAuthCookie(std::string *cookie_out)
     std::string cookie = COOKIEAUTH_USER + ":" + HexStr(rand_pwd);
 
     /** the umask determines what permissions are used to create this file -
-     * these are set to 077 in init.cpp unless overridden with -sysperms.
+     * these are set to 077 in init.cpp.
      */
     std::ofstream file;
     fs::path filepath_tmp = GetAuthCookieFile(true);

src/wallet/init.cpp

@@ -122,9 +122,6 @@ bool WalletInit::ParameterInteraction() const
         return InitError(Untranslated("-zapwallettxes has been removed. If you are attempting to remove a stuck transaction from your wallet, please use abandontransaction instead."));
     }
 
-    if (gArgs.GetBoolArg("-sysperms", false))
-        return InitError(Untranslated("-sysperms is not allowed in combination with enabled wallet functionality"));
-
     return true;
 }