protocol/Result: move command_list_num to class Response

src/client/Response.cxx

@@ -65,8 +65,8 @@ Response::Error(enum ack code, const char *msg)
 void
 Response::FormatError(enum ack code, const char *fmt, ...)
 {
-	Format("ACK [%i@%i] {%s} ",
-	       (int)code, command_list_num, current_command);
+	Format("ACK [%i@%u] {%s} ",
+	       (int)code, list_index, current_command);
 
 	va_list args;
 	va_start(args, fmt);

src/client/Response.hxx

@@ -31,8 +31,15 @@ class Client;
 class Response {
 	Client &client;
 
+	/**
+	 * This command's index in the command list.  Used to generate
+	 * error messages.
+	 */
+	const unsigned list_index;
+
 public:
-	explicit Response(Client &_client):client(_client) {}
+	Response(Client &_client, unsigned _list_index)
+		:client(_client), list_index(_list_index) {}
 
 	Response(const Response &) = delete;
 	Response &operator=(const Response &) = delete;

src/command/AllCommands.cxx

@@ -363,11 +363,9 @@ command_checked_lookup(Response &r, unsigned permission,
 CommandResult
 command_process(Client &client, unsigned num, char *line)
 {
-	Response r(client);
+	Response r(client, num);
 	Error error;
 
-	command_list_num = num;
-
 	/* get the command name (first word on the line) */
 	/* we have to set current_command because Response::Error()
 	   expects it to be set */
@@ -427,7 +425,6 @@ command_process(Client &client, unsigned num, char *line)
 		: CommandResult::ERROR;
 
 	current_command = nullptr;
-	command_list_num = 0;
 
 	return ret;
 }

src/protocol/Result.cxx

@@ -22,7 +22,6 @@
 #include "client/Client.hxx"
 
 const char *current_command;
-int command_list_num;
 
 void
 command_success(Client &client)

src/protocol/Result.hxx

@@ -25,7 +25,6 @@
 class Client;
 
 extern const char *current_command;
-extern int command_list_num;
 
 void
 command_success(Client &client);

test/test_protocol.cxx

@@ -37,7 +37,7 @@ void
 ArgParserTest::TestRange()
 {
 	Client &client = *(Client *)nullptr;
-	Response r(client);
+	Response r(client, 0);
 
 	RangeArg range;