refactor command registration
authorZachary T Welch <zw@superlucidity.net>
Thu, 19 Nov 2009 16:38:17 +0000 (08:38 -0800)
committerZachary T Welch <zw@superlucidity.net>
Fri, 20 Nov 2009 22:52:56 +0000 (14:52 -0800)
Refactors the command registration to use helpers to simplify the code.
The unregistration routines were made more flexible by allowing them
to operate on a single command, such that one can remove all of a
commands children in one step (perhaps before adding back a 'config'
subcommand that allows getting the others back).  Eliminates a bit
of duplicated code and adds full API documentation for these routines.

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

index 538c07bb917392981622af66327d30c6774fe649..87a898f293eb9b868a3ea1287e7ce82c788f60c5 100644 (file)
@@ -233,33 +233,69 @@ static void command_add_child(struct command **head, struct command *c)
        cc->next = c;
 }
 
-struct command* register_command(struct command_context *context,
-               struct command *parent, char *name, command_handler_t handler,
-               enum command_mode mode, char *help)
+static struct command **command_list_for_parent(
+               struct command_context *cmd_ctx, struct command *parent)
 {
-       if (!context || !name)
-               return NULL;
+       return parent ? &parent->children : &cmd_ctx->commands;
+}
 
-       struct command **head = parent ? &parent->children : &context->commands;
-       struct command *c = command_find(*head, name);
-       if (NULL != c)
-               return c;
+static struct command *command_new(struct command_context *cmd_ctx,
+               struct command *parent, const char *name,
+               command_handler_t handler, enum command_mode mode,
+               const char *help)
+{
+       assert(name);
 
-       c = malloc(sizeof(struct command));
+       struct command *c = malloc(sizeof(struct command));
+       memset(c, 0, sizeof(struct command));
 
        c->name = strdup(name);
        c->parent = parent;
-       c->children = NULL;
        c->handler = handler;
        c->mode = mode;
-       c->next = NULL;
 
-       command_add_child(head, c);
+       command_add_child(command_list_for_parent(cmd_ctx, parent), c);
 
        command_helptext_add(command_name_list(c), help);
 
-       /* just a placeholder, no handler */
-       if (c->handler == NULL)
+       return c;
+}
+static void command_free(struct command *c)
+{
+       /// @todo if command has a handler, unregister its jim command!
+
+       while (NULL != c->children)
+       {
+               struct command *tmp = c->children;
+               c->children = tmp->next;
+               command_free(tmp);
+       }
+
+       if (c->name)
+               free(c->name);
+       free(c);
+}
+
+struct command* register_command(struct command_context *context,
+               struct command *parent, const char *name,
+               command_handler_t handler, enum command_mode mode,
+               const char *help)
+{
+       if (!context || !name)
+               return NULL;
+
+       struct command **head = command_list_for_parent(context, parent);
+       struct command *c = command_find(*head, name);
+       if (NULL != c)
+       {
+               LOG_ERROR("command '%s' is already registered in '%s' context",
+                               name, parent ? parent->name : "<global>");
+               return c;
+       }
+
+       c = command_new(context, parent, name, handler, mode, help);
+       /* if allocation failed or it is a placeholder (no handler), we're done */
+       if (NULL == c || NULL == c->handler)
                return c;
 
        const char *full_name = command_name(c, '_');
@@ -281,85 +317,43 @@ struct command* register_command(struct command_context *context,
        return c;
 }
 
-int unregister_all_commands(struct command_context *context)
+int unregister_all_commands(struct command_context *context,
+               struct command *parent)
 {
-       struct command *c, *c2;
-
        if (context == NULL)
                return ERROR_OK;
 
-       while (NULL != context->commands)
+       struct command **head = command_list_for_parent(context, parent);
+       while (NULL != *head)
        {
-               c = context->commands;
-
-               while (NULL != c->children)
-               {
-                       c2 = c->children;
-                       c->children = c->children->next;
-                       free(c2->name);
-                       c2->name = NULL;
-                       free(c2);
-                       c2 = NULL;
-               }
-
-               context->commands = context->commands->next;
-
-               free(c->name);
-               c->name = NULL;
-               free(c);
-               c = NULL;
+               struct command *tmp = *head;
+               *head = tmp->next;
+               command_free(tmp);
        }
 
        return ERROR_OK;
 }
 
-int unregister_command(struct command_context *context, char *name)
+int unregister_command(struct command_context *context,
+               struct command *parent, const char *name)
 {
-       struct command *c, *p = NULL, *c2;
-
        if ((!context) || (!name))
                return ERROR_INVALID_ARGUMENTS;
 
-       /* find command */
-       c = context->commands;
-
-       while (NULL != c)
+       struct command *p = NULL;
+       struct command **head = command_list_for_parent(context, parent);
+       for (struct command *c = *head; NULL != c; p = c, c = c->next)
        {
-               if (strcmp(name, c->name) == 0)
-               {
-                       /* unlink command */
-                       if (p)
-                       {
-                               p->next = c->next;
-                       }
-                       else
-                       {
-                               /* first element in command list */
-                               context->commands = c->next;
-                       }
+               if (strcmp(name, c->name) != 0)
+                       continue;
 
-                       /* unregister children */
-                       while (NULL != c->children)
-                       {
-                               c2 = c->children;
-                               c->children = c->children->next;
-                               free(c2->name);
-                               c2->name = NULL;
-                               free(c2);
-                               c2 = NULL;
-                       }
-
-                       /* delete command */
-                       free(c->name);
-                       c->name = NULL;
-                       free(c);
-                       c = NULL;
-                       return ERROR_OK;
-               }
+               if (p)
+                       p->next = c->next;
+               else
+                       *head = c->next;
 
-               /* remember the last command for unlinking */
-               p = c;
-               c = c->next;
+               command_free(c);
+               return ERROR_OK;
        }
 
        return ERROR_OK;
index def0935a737e7a734d22fe89015da8938b8a8ec8..a7b422adf899594a818dd8d05ac27634b40158e3 100644 (file)
@@ -176,12 +176,53 @@ struct command
  */
 char *command_name(struct command *c, char delim);
 
-struct command* register_command(struct command_context *context,
-               struct command *parent, char *name, command_handler_t handler,
-               enum command_mode mode, char *help);
+/**
+ * Register a command @c handler that can be called from scripts during
+ * the execution @c mode specified.
+ *
+ * If @c parent is non-NULL, the new command will be registered as a
+ * sub-command under it; otherwise, it will be available as a top-level
+ * command.
+ *
+ * A conventioal format should be used for help strings, to provide both
+ * usage and basic information:
+ * @code
+ * "@<options@> ... - some explanation text"
+ * @endcode
+ *
+ * @param cmd_ctx The command_context in which to register the command.
+ * @param parent Register this command as a child of this, or NULL to
+ * register a top-level command.
+ * @param name The name of the command to register, which must not have
+ * been registered previously.
+ * @param handler The callback function that will be called.  If NULL,
+ * then the command serves as a placeholder for its children or a script.
+ * @param mode The command mode(s) in which this command may be run.
+ * @param help The help text that will be displayed to the user.
+ * @returns The new command, if successful; otherwise, NULL.
+ */
+struct command* register_command(struct command_context *cmd_ctx,
+               struct command *parent, const char *name,
+               command_handler_t handler, enum command_mode mode,
+               const char *help);
 
-int unregister_command(struct command_context *context, char *name);
-int unregister_all_commands(struct command_context *context);
+/**
+ * Unregisters command @c name from the given context, @c cmd_ctx.
+ * @param cmd_ctx The context of the registered command.
+ * @param parent The parent of the given command, or NULL.
+ * @param name The name of the command to unregister.
+ * @returns ERROR_OK on success, or an error code.
+ */
+int unregister_command(struct command_context *cmd_ctx,
+               struct command *parent, const char *name);
+/**
+ * Unregisters all commands from the specfied context.
+ * @param cmd_ctx The context that will be cleared of registered commands.
+ * @param parent If given, only clear commands from under this one command.
+ * @returns ERROR_OK on success, or an error code.
+ */
+int unregister_all_commands(struct command_context *cmd_ctx,
+               struct command *parent);
 
 void command_set_output_handler(struct command_context* context,
                command_output_handler_t output_handler, void *priv);
index b7781a6b6d37332693838815f662347bdcfd80ca..8e8ceac45eb8ece54df1b877b6438d1ae2e1631f 100644 (file)
@@ -278,7 +278,7 @@ int openocd_main(int argc, char *argv[])
        httpd_stop();
 #endif
 
-       unregister_all_commands(cmd_ctx);
+       unregister_all_commands(cmd_ctx, NULL);
 
        /* free commandline interface */
        command_done(cmd_ctx);

Linking to existing account procedure

If you already have an account and want to add another login method you MUST first sign in with your existing account and then change URL to read https://review.openocd.org/login/?link to get to this page again but this time it'll work for linking. Thank you.

SSH host keys fingerprints

1024 SHA256:YKx8b7u5ZWdcbp7/4AeXNaqElP49m6QrwfXaqQGJAOk gerrit-code-review@openocd.zylin.com (DSA)
384 SHA256:jHIbSQa4REvwCFG4cq5LBlBLxmxSqelQPem/EXIrxjk gerrit-code-review@openocd.org (ECDSA)
521 SHA256:UAOPYkU9Fjtcao0Ul/Rrlnj/OsQvt+pgdYSZ4jOYdgs gerrit-code-review@openocd.org (ECDSA)
256 SHA256:A13M5QlnozFOvTllybRZH6vm7iSt0XLxbA48yfc2yfY gerrit-code-review@openocd.org (ECDSA)
256 SHA256:spYMBqEYoAOtK7yZBrcwE8ZpYt6b68Cfh9yEVetvbXg gerrit-code-review@openocd.org (ED25519)
+--[ED25519 256]--+
|=..              |
|+o..   .         |
|*.o   . .        |
|+B . . .         |
|Bo. = o S        |
|Oo.+ + =         |
|oB=.* = . o      |
| =+=.+   + E     |
|. .=o   . o      |
+----[SHA256]-----+
2048 SHA256:0Onrb7/PHjpo6iVZ7xQX2riKN83FJ3KGU0TvI0TaFG4 gerrit-code-review@openocd.zylin.com (RSA)