dird: Fix memory leak with configure usage string.

As the old buffer was defined as static inside the
get_configure_parameter() function it means its scope is still active at
the time the daemon ends and it will never be freed and as such
smartalloc whines in the following way:

bareos-dir: smartall.c:414-0 Orphaned buffer: bareos-dir 10016 bytes at
6e6b68 from mem_pool.c:242

The new approach is to use a static global variable and a dynamic
allocate of the POOL_MEM buffer and an extra cleanup function
destroy_configure_usage_string() which is called from terminate_dird().
I also renamed the original function from get_configure_parameter() to
get_configure_usage_string() which describes the function a bit better.

src/dird/dird.c

@@ -467,6 +467,7 @@ void terminate_dird(int sig)
    already_here = true;
    debug_level = 0;                   /* turn off debug */
 
+   destroy_configure_usage_string();
    stop_statistics_thread();
    stop_watchdog();
    db_sql_pool_destroy();

src/dird/dird_conf.c

@@ -59,6 +59,7 @@ extern struct s_kw RunFields[];
  */
 static RES *sres_head[R_LAST - R_FIRST + 1];
 static RES **res_head = sres_head;
+static POOL_MEM *configure_usage_string = NULL;
 
 /*
  * Set default indention e.g. 2 spaces.
@@ -901,7 +902,7 @@ bool print_config_schema_json(POOL_MEM &buffer)
 }
 #endif
 
-static inline bool cmdline_item(POOL_MEM &buffer, RES_ITEM *item)
+static inline bool cmdline_item(POOL_MEM *buffer, RES_ITEM *item)
 {
    POOL_MEM temp;
    POOL_MEM key;
@@ -939,7 +940,7 @@ static inline bool cmdline_item(POOL_MEM &buffer, RES_ITEM *item)
    return true;
 }
 
-static inline bool cmdline_items(POOL_MEM &buffer, RES_ITEM items[])
+static inline bool cmdline_items(POOL_MEM *buffer, RES_ITEM items[])
 {
    if (!items) {
       return false;
@@ -953,35 +954,47 @@ static inline bool cmdline_items(POOL_MEM &buffer, RES_ITEM items[])
 }
 
 /*
- * Get the parameter string for the console "configure" command.
+ * Get the usage string for the console "configure" command.
+ *
  * This will be all available resource directives.
  * They are formated in a way to be usable for command line completion.
  */
-const char *get_configure_parameter()
+const char *get_configure_usage_string()
 {
-   static POOL_MEM buffer;
    POOL_MEM resourcename;
 
+   if (!configure_usage_string) {
+      configure_usage_string = new POOL_MEM(PM_BSOCK);
+   }
+
    /*
-    * Only fill the buffer once. The content is static.
+    * Only fill the configure_usage_string once. The content is static.
     */
-   if (buffer.strlen() == 0) {
-      buffer.strcpy("add [");
+   if (configure_usage_string->strlen() == 0) {
+      configure_usage_string->strcpy("add [");
       for (int r = 0; resources[r].name; r++) {
          if (resources[r].items) {
             resourcename.strcpy(resources[r].name);
             resourcename.toLower();
-            buffer.strcat(resourcename);
-            cmdline_items(buffer, resources[r].items);
+            configure_usage_string->strcat(resourcename);
+            cmdline_items(configure_usage_string, resources[r].items);
          }
          if (resources[r+1].items) {
-            buffer.strcat("] | [");
+            configure_usage_string->strcat("] | [");
          }
       }
-      buffer.strcat("]");
+      configure_usage_string->strcat("]");
    }
 
-   return buffer.c_str();
+   return configure_usage_string->c_str();
+}
+
+void destroy_configure_usage_string()
+{
+   if (configure_usage_string) {
+      delete configure_usage_string;
+      configure_usage_string = NULL;
+   }
 }
 
 /*

src/dird/protos.h

@@ -87,7 +87,8 @@ json_t *json_datatype(const int type, RES_ITEM items[]);
 const char *auth_protocol_to_str(uint32_t auth_protocol);
 const char *level_to_str(int level);
 extern "C" char *job_code_callback_director(JCR *jcr, const char*);
-const char *get_configure_parameter();
+const char *get_configure_usage_string();
+void destroy_configure_usage_string();
 bool populate_defs();
 
 /* expand.c */

src/dird/ua_cmds.c

@@ -237,7 +237,7 @@ static struct cmdstruct commands[] = {
    { NT_("cancel"), cancel_cmd, _("Cancel a job"),
      NT_("storage=<storage-name> | jobid=<jobid> | job=<job-name> | ujobid=<unique-jobid> | state=<job_state> | all yes"), false, true },
    { NT_("configure"), configure_cmd, _("Configure director resources"),
-     NT_(get_configure_parameter()), false, true },
+     NT_(get_configure_usage_string()), false, true },
    { NT_("create"), create_cmd, _("Create DB Pool from resource"),
      NT_("pool=<pool-name>"), false, true },
    { NT_("delete"), delete_cmd, _("Delete volume, pool or job"),