Don't allow /alias to overwrite standard command

src/command/command.c

@@ -1120,6 +1120,16 @@ cmd_uninit(void)
     autocomplete_free(aliases_ac);
 }
 
+gboolean
+cmd_exists(char *cmd)
+{
+    if (commands_ac == NULL) {
+        return FALSE;
+    } else {
+        return autocomplete_contains(commands_ac, cmd);
+    }
+}
+
 void
 cmd_autocomplete_add(char *value)
 {

src/command/command.h

@@ -41,6 +41,8 @@ gboolean cmd_execute(const char * const command, const char * const inp);
 gboolean cmd_execute_alias(const char * const inp, gboolean *ran);
 gboolean cmd_execute_default(const char * const inp);
 
+gboolean cmd_exists(char *cmd);
+
 GSList * cmd_get_basic_help(void);
 GSList * cmd_get_settings_help(void);
 GSList * cmd_get_presence_help(void);

src/command/commands.c

@@ -1830,21 +1830,24 @@ cmd_alias(gchar **args, struct cmd_help_t help)
             cons_show("Usage: %s", help.usage);
             return TRUE;
         } else {
+            GString *ac_value = g_string_new("/");
+            g_string_append(ac_value, alias);
+
             char *value = args[2];
             if (value == NULL) {
                 cons_show("Usage: %s", help.usage);
+                g_string_free(ac_value, TRUE);
+                return TRUE;
+            } else if (cmd_exists(ac_value->str)) {
+                cons_show("Command or alias '%s' already exists.");
+                g_string_free(ac_value, TRUE);
                 return TRUE;
             } else {
-                if (prefs_add_alias(alias, value) == TRUE) {
-                    GString *ac_value = g_string_new("/");
-                    g_string_append(ac_value, alias);
-                    cmd_autocomplete_add(ac_value->str);
-                    cmd_alias_add(alias);
-                    g_string_free(ac_value, TRUE);
-                    cons_show("Command alias added /%s -> %s", alias, value);
-                } else {
-                    cons_show("Command alias /%s already exists.", alias);
-                }
+                prefs_add_alias(alias, value);
+                cmd_autocomplete_add(ac_value->str);
+                cmd_alias_add(alias);
+                cons_show("Command alias added /%s -> %s", alias, value);
+                g_string_free(ac_value, TRUE);
                 return TRUE;
             }
         }

src/tools/autocomplete.c

@@ -132,6 +132,21 @@ autocomplete_get_list(Autocomplete ac)
     return copy;
 }
 
+gboolean
+autocomplete_contains(Autocomplete ac, char *value)
+{
+    GSList *curr = ac->items;
+
+    while(curr) {
+        if (strcmp(curr->data, value) == 0) {
+            return TRUE;
+        }
+        curr = g_slist_next(curr);
+    }
+
+    return FALSE;
+}
+
 gchar *
 autocomplete_complete(Autocomplete ac, gchar *search_str)
 {

src/tools/autocomplete.h

@@ -56,4 +56,6 @@ char * autocomplete_param_no_with_func(char *input, int *size, char *command,
     int arg_number, autocomplete_func func);
 
 void autocomplete_reset(Autocomplete ac);
+
+gboolean autocomplete_contains(Autocomplete ac, char *value);
 #endif