add CMD_NAME variable in command_invocation

Update CMD_NAME from its migratory home in CMD_ARGV[-1] to cmd->name.
Allows CMD_ARGV++ idiom to be used safely in command handlers.

2 files changed, 9 insertions, 8 deletions

diff --git a/src/helper/command.c b/src/helper/command.c
index 96d23ab4..b9d0d087 100644
--- a/src/helper/command.c
+++ b/src/helper/command.c
@@ -102,8 +102,7 @@ static int script_command(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
 
 	script_debug(interp, c->name, argc, argv);
 
-	words = malloc(sizeof(char *) * (argc + 1));
-	words[0] = c->name;
+	words = malloc(argc * sizeof(char *));
 	for (i = 0; i < argc; i++)
 	{
 		int len;
@@ -113,12 +112,12 @@ static int script_command(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
 			/* hit an end of line comment */
 			break;
 		}
-		words[i + 1] = strdup(w);
-		if (words[i + 1] == NULL)
+		words[i] = strdup(w);
+		if (words[i] == NULL)
 		{
 			int j;
 			for (j = 0; j < i; j++)
-				free(words[j + 1]);
+				free(words[j]);
 			free(words);
 			return JIM_ERR;
 		}
@@ -143,7 +142,7 @@ static int script_command(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
 	log_add_callback(tcl_output, tclOutput);
 
 	// turn words[0] into CMD_ARGV[-1] with this cast
-	retval = run_command(context, c, (const char **)words + 1, nwords);
+	retval = run_command(context, c, (const char **)words, nwords);
 
 	log_remove_callback(tcl_output, tclOutput);
 
@@ -152,7 +151,7 @@ static int script_command(Jim_Interp *interp, int argc, Jim_Obj *const *argv)
 	Jim_DecrRefCount(interp, tclOutput);
 
 	for (i = 0; i < nwords; i++)
-		free(words[i + 1]);
+		free(words[i]);
 	free(words);
 
 	int *return_retval = Jim_GetAssocData(interp, "retval");
@@ -449,6 +448,7 @@ static int run_command(struct command_context *context,
 
 	struct command_invocation cmd = {
 			.ctx = context,
+			.name = c->name,
 			.argc = num_words - start_word - 1,
 			.argv = words + start_word + 1,
 		};
diff --git a/src/helper/command.h b/src/helper/command.h
index b8ea3a4a..62231fc8 100644
--- a/src/helper/command.h
+++ b/src/helper/command.h
@@ -87,6 +87,7 @@ struct command_context
  */
 struct command_invocation {
 	struct command_context *ctx;
+	const char *name;
 	unsigned argc;
 	const char **argv;
 };
@@ -149,7 +150,7 @@ struct command_invocation {
  * Use this macro to access the name of the command being handled,
  * rather than accessing the variable directly.  It may be moved.
  */
-#define CMD_NAME CMD_ARGV[-1]
+#define CMD_NAME cmd->name
 
 
 /// The type signature for commands' handler functions.