add command_name helper
authorZachary T Welch <zw@superlucidity.net>
Wed, 11 Nov 2009 13:26:17 +0000 (05:26 -0800)
committerZachary T Welch <zw@superlucidity.net>
Wed, 11 Nov 2009 20:15:39 +0000 (12:15 -0800)
The command_name function returns a malloced string for a given
command and its parents.  This can be used to display a message
to the user, but it is used internally to handle registration
and syntax errors.  This helps permit arbitrary command nesting.

src/helper/command.c
src/helper/command.h

index c632702..86158d7 100644 (file)
@@ -217,32 +217,22 @@ command_t* register_command(command_context_t *context, command_t *parent, char
        if (c->handler == NULL)
                return c;
 
-       /* If this is a two level command, e.g. "flash banks", then the
-        * "unknown" proc in startup.tcl must redirect to  this command.
-        *
-        * "flash banks" is translated by "unknown" to "flash_banks"
-        * if such a proc exists
-        */
-       /* Print help for command */
-       const char *t1="";
-       const char *t2="";
-       const char *t3="";
-       /* maximum of two levels :-) */
-       if (c->parent != NULL)
-       {
-               t1 = c->parent->name;
-               t2="_";
-       }
-       t3 = c->name;
-       const char *full_name = alloc_printf("ocd_%s%s%s", t1, t2, t3);
-       Jim_CreateCommand(interp, full_name, script_command, c, NULL);
-       free((void *)full_name);
+       const char *full_name = command_name(c, '_');
+
+       const char *ocd_name = alloc_printf("ocd_%s", full_name);
+       Jim_CreateCommand(interp, ocd_name, script_command, c, NULL);
+       free((void *)ocd_name);
 
        /* we now need to add an overrideable proc */
-       const char *override_name = alloc_printf("proc %s%s%s {args} {if {[catch {eval ocd_%s%s%s $args}]==0} {return \"\"} else { return -code error }", t1, t2, t3, t1, t2, t3);
+       const char *override_name = alloc_printf("proc %s {args} {"
+                       "if {[catch {eval ocd_%s $args}] == 0} "
+                       "{return \"\"} else {return -code error}}",
+                       full_name, full_name);
        Jim_Eval_Named(interp, override_name, __THIS__FILE__, __LINE__);
        free((void *)override_name);
 
+       free((void *)full_name);
+
        /* accumulate help text in Tcl helptext list.  */
        Jim_Obj *helptext = Jim_GetGlobalVariableStr(interp, "ocd_helptext", JIM_ERRMSG);
        if (Jim_IsShared(helptext))
@@ -404,6 +394,28 @@ void command_print(command_context_t *context, const char *format, ...)
        va_end(ap);
 }
 
+static char *__command_name(struct command_s *c, char delim, unsigned extra)
+{
+       char *name;
+       unsigned len = strlen(c->name);
+       if (NULL == c->parent) {
+               // allocate enough for the name, child names, and '\0'
+               name = malloc(len + extra + 1);
+               strcpy(name, c->name);
+       } else {
+               // parent's extra must include both the space and name
+               name = __command_name(c->parent, delim, 1 + len + extra);
+               char dstr[2] = { delim, 0 };
+               strcat(name, dstr);
+               strcat(name, c->name);
+       }
+       return name;
+}
+char *command_name(struct command_s *c, char delim)
+{
+       return __command_name(c, delim, 0);
+}
+
 static int run_command(command_context_t *context,
                command_t *c, char *words[], unsigned num_words)
 {
@@ -419,17 +431,12 @@ static int run_command(command_context_t *context,
        if (retval == ERROR_COMMAND_SYNTAX_ERROR)
        {
                /* Print help for command */
-               const char *t1="";
-               const char *t2="";
-               const char *t3="";
-               /* maximum of two levels :-) */
-               if (c->parent != NULL)
-               {
-                       t1 = c->parent->name;
-                       t2=" ";
-               }
-               t3 = c->name;
-               command_run_linef(context, "help {%s%s%s}", t1, t2, t3);
+               char *full_name = command_name(c, ' ');
+               if (NULL != full_name) {
+                       command_run_linef(context, "help %s", full_name);
+                       free(full_name);
+               } else
+                       retval = -ENOMEM;
        }
        else if (retval == ERROR_COMMAND_CLOSE_CONNECTION)
        {
index 0b86b88..732fa52 100644 (file)
@@ -84,6 +84,16 @@ typedef struct command_s
        struct command_s *next;
 } command_t;
 
+/**
+ * @param c The command to be named.
+ * @param delim The character to place between command names.
+ * @returns A malloc'd string containing the full command name,
+ * which may include one or more ancestor components.  Multiple names
+ * are separated by single spaces.  The caller must free() the string
+ * when done with it.
+ */
+char *command_name(struct command_s *c, char delim);
+
 command_t* register_command(command_context_t *context,
                command_t *parent, char *name,
                int (*handler)(struct command_context_s *context,