helper/command: handle empty "usage" with add_help_text/add_usage_text

By using the command "add_help_text" to add a help text to a TCL
procedure it implicitly creates a new command_registration struct
that has field .usage set to NULL. This triggers a debug message
	BUG: command '%s' does not have the '.usage' field filled out

Use an empty string if usage field is NULL.

Plus, do not annoy the user with a LOG_INFO when the command
"add_usage_text" replaces an empty usage.

Change-Id: I4a72646e0fb704ba354f938d774055540cde3967
Signed-off-by: Antonio Borneo <borneo.antonio@gmail.com>
Reviewed-on: http://openocd.zylin.com/5025
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>

diff --git a/src/helper/command.c b/src/helper/command.c
index 869eff559cdd0836b760744bd1052439e093807a..ec66c2d2982e2050621a05496a04f93d7d831e3e 100644 (file)
--- a/src/helper/command.c
+++ b/src/helper/command.c
@@ -1119,7 +1119,7 @@ int help_add_command(struct command_context *cmd_ctx, struct command *parent,
                        .name = cmd_name,
                        .mode = COMMAND_ANY,
                        .help = help_text,
-                       .usage = usage,
+                       .usage = usage ? : "",
                };
                nc = register_command(cmd_ctx, parent, &cr);
                if (NULL == nc) {
@@ -1144,8 +1144,9 @@ int help_add_command(struct command_context *cmd_ctx, struct command *parent,
        if (usage) {
                bool replaced = false;
                if (nc->usage) {
+                       if (*nc->usage)
+                               replaced = true;
                        free(nc->usage);
-                       replaced = true;
                }
                nc->usage = strdup(usage);
                if (replaced)