Add logic to automatically unload module on exit; Several patches from Mike Smith

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5528 42af7a65-404d-4744-a932-0658087f49c3

binfmt/Makefile

@@ -52,6 +52,10 @@ ifeq ($(CONFIG_BINFMT_EXEPATH),y)
 BINFMT_CSRCS += binfmt_exepath.c
 endif
 
+ifeq ($(CONFIG_SCHED_HAVE_PARENT),y)
+BINFMT_CSRCS += binfmt_schedunload.c
+endif
+
 # Symbol table source files
 
 BINFMT_CSRCS += symtab_findbyname.c symtab_findbyvalue.c

binfmt/binfmt_exec.c

@@ -74,7 +74,9 @@
  *
  * Description:
  *   This is a convenience function that wraps load_ and exec_module into
- *   one call.
+ *   one call.  If CONFIG_SCHED_ONEXIT is also defined, this function will
+ *   automatically call schedule_unload() to unload the module when task
+ *   exits.
  *
  * Input Parameter:
  *   filename - Fulll path to the binary to be loaded
@@ -84,7 +86,7 @@
  *
  * Returned Value:
  *   This is an end-user function, so it follows the normal convention:
- *   Returns the PID of the exec'ed module.  On failure, it.returns
+ *   It returns the PID of the exec'ed module.  On failure, it returns
  *   -1 (ERROR) and sets errno appropriately.
  *
  ****************************************************************************/
@@ -92,6 +94,66 @@
 int exec(FAR const char *filename, FAR const char **argv,
          FAR const struct symtab_s *exports, int nexports)
 {
+#ifdef CONFIG_SCHED_ONEXIT
+  FAR struct binary_s *bin;
+  int errorcode;
+  int ret;
+
+  /* Allocate the load information */
+
+  bin = (FAR struct binary_s *)kzalloc(sizeof(struct binary_s));
+  if (!bin)
+    {
+      set_errno(ENOMEM);
+      return ERROR;
+    }
+
+  /* Load the module into memory */
+
+  bin->filename = filename;
+  bin->exports  = exports;
+  bin->nexports = nexports;
+
+  ret = load_module(bin);
+  if (ret < 0)
+    {
+      bdbg("ERROR: Failed to load program '%s'\n", filename);
+      kfree(bin);
+      return ERROR;
+    }
+
+  /* Disable pre-emption so that the executed module does
+   * not return until we get a chance to connect the on_exit
+   * handler.
+   */
+
+  sched_lock();
+
+  /* Then start the module */
+
+  ret = exec_module(bin);
+  if (ret < 0)
+    {
+      bdbg("ERROR: Failed to execute program '%s'\n", filename);
+      sched_unlock();
+      unload_module(bin);
+      kfree(bin);
+      return ERROR;
+    }
+
+  /* Set up to unload the module (and free the binary_s structure)
+   * when the task exists.
+   */
+
+  ret = schedul_unload(ret, bin);
+  if (ret < 0)
+    {
+      bdbg("ERROR: Failed to schedul unload '%s'\n", filename);
+    }
+
+  sched_unlock();
+  return ret;
+#else
   struct binary_s bin;
   int ret;
 
@@ -119,7 +181,10 @@ int exec(FAR const char *filename, FAR const char **argv,
       return ERROR;
     }
 
+  /* TODO:  How does the module get unloaded in this case? */
+
   return ret;
+#endif
 }
 
 #endif /* CONFIG_BINFMT_DISABLE */

binfmt/builtin.c

@@ -89,6 +89,7 @@ static struct binfmt_s g_builtin_binfmt =
 static int builtin_loadbinary(struct binary_s *binp)
 {
   FAR const char *filename;
+  FAR const struct builtin_s *b;
   int fd;
   int index;
   int ret;
@@ -134,9 +135,10 @@ static int builtin_loadbinary(struct binary_s *binp)
    * the priority.  That is a bug and needs to be fixed.
    */
 
-  binp->entrypt   = g_builtins[index].main;
-  binp->stacksize = g_builtins[index].stacksize;
-  binp->priority  = g_builtins[index].priority;
+  b = builtin_for_index(index);
+  binp->entrypt   = b->main;
+  binp->stacksize = b->stacksize;
+  binp->priority  = b->priority;
   return OK;
 }
 

binfmt/libbuiltin/libbuiltin_getname.c

@@ -83,10 +83,14 @@
 
 FAR const char *builtin_getname(int index)
 {
-  if (index < 0 || index >= number_builtins())
-   {
-     return NULL;
-   }
+  struct builtin_s *b;
 
-  return g_builtins[index].name;
+  b = builtin_for_index(index);
+
+  if (b != NULL)
+    {
+      return b->name;
+    }
+
+  return NULL;
 }

binfmt/libbuiltin/libbuiltin_isavail.c

@@ -80,18 +80,19 @@
  * Name: builtin_isavail
  *
  * Description:
- *   Return the index into the table of applications for the applicaiton with
+ *   Return the index into the table of applications for the application with
  *   the name 'appname'.
  *
  ****************************************************************************/
 
 int builtin_isavail(FAR const char *appname)
 {
+  FAR const char *n;
   int i;
 
-  for (i = 0; g_builtins[i].name; i++)
+  for (i = 0; n = builtin_getname(i); i++)
     {
-      if (!strncmp(g_builtins[i].name, appname, NAME_MAX))
+      if (!strncmp(n, appname, NAME_MAX))
         {
           return i;
         }