Merge Nuttx r5554

7 files changed, 428 insertions, 16 deletions

diff --git a/nuttx/binfmt/Makefile b/nuttx/binfmt/Makefile
index 49dcd3d32..2f692beb1 100644
--- a/nuttx/binfmt/Makefile
+++ b/nuttx/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
diff --git a/nuttx/binfmt/binfmt_exec.c b/nuttx/binfmt/binfmt_exec.c
index d878c8cc5..4226b6cfc 100644
--- a/nuttx/binfmt/binfmt_exec.c
+++ b/nuttx/binfmt/binfmt_exec.c
@@ -43,6 +43,7 @@
 #include <debug.h>
 #include <errno.h>
 
+#include <nuttx/kmalloc.h>
 #include <nuttx/binfmt/binfmt.h>
 
 #include "binfmt_internal.h"
@@ -74,7 +75,9 @@
  *
  * 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 +87,7 @@
  *
  * 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 +95,66 @@
 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 pid;
+  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 */
+
+  pid = exec_module(bin);
+  if (pid < 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 = schedule_unload(pid, bin);
+  if (ret < 0)
+    {
+      bdbg("ERROR: Failed to schedul unload '%s'\n", filename);
+    }
+
+  sched_unlock();
+  return pid;
+#else
   struct binary_s bin;
   int ret;
 
@@ -119,7 +182,10 @@ 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 */
diff --git a/nuttx/binfmt/binfmt_loadmodule.c b/nuttx/binfmt/binfmt_loadmodule.c
index 4f3dc6952..322ed2c48 100644
--- a/nuttx/binfmt/binfmt_loadmodule.c
+++ b/nuttx/binfmt/binfmt_loadmodule.c
@@ -84,6 +84,7 @@
 static int load_default_priority(FAR struct binary_s *bin)
 {
   struct sched_param param;
+  int ret;
 
   /* Get the priority of this thread */
 
@@ -97,6 +98,7 @@ static int load_default_priority(FAR struct binary_s *bin)
   /* Save that as the priority of child thread */
 
   bin->priority = param.sched_priority;
+  return ret;
 }
 
 /****************************************************************************
@@ -180,7 +182,7 @@ int load_module(FAR struct binary_s *bin)
     {
       /* Set the default priority of the new program. */
 
-      ret = load_default_priority(bin)
+      ret = load_default_priority(bin);
       if (ret < 0)
         {
           /* The errno is already set in this case */
diff --git a/nuttx/binfmt/binfmt_schedunload.c b/nuttx/binfmt/binfmt_schedunload.c
new file mode 100644
index 000000000..972d17963
--- /dev/null
+++ b/nuttx/binfmt/binfmt_schedunload.c
@@ -0,0 +1,333 @@
+/****************************************************************************
+ * binfmt/binfmt_schedunload.c
+ *
+ *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sched.h>
+#include <debug.h>
+#include <errno.h>
+
+#include <nuttx/kmalloc.h>
+#include <nuttx/binfmt/binfmt.h>
+
+#include "binfmt_internal.h"
+
+#if !defined(CONFIG_BINFMT_DISABLE) && defined(CONFIG_SCHED_HAVE_PARENT)
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+FAR struct binary_s *g_unloadhead;
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: unload_list_add
+ *
+ * Description:
+ *   If CONFIG_SCHED_HAVE_PARENT is defined then schedul_unload() will
+ *   manage instances of struct binary_s allocated with kmalloc.  It
+ *   will keep the binary data in a link list and when SIGCHLD is received
+ *   (meaning that the task has exit'ed, schedul_unload() will find the
+ *   data, unload the module, and free the structure.
+ *
+ *   This function will add one structure to the linked list
+ *
+ * Input Parameter:
+ *   pid - The task ID of the child task
+ *   bin - This structure must have been allocated with kmalloc() and must
+ *         persist until the task unloads
+
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+static void unload_list_add(pid_t pid, FAR struct binary_s *bin)
+{
+  irqstate_t flags;
+
+  /* Save the PID in the structure so that we recover it later */
+
+  bin->pid = pid;
+
+  /* Disable deliver of any signals while we muck with the list.  The graceful
+   * way to do this would be block delivery of SIGCHLD would be with
+   * sigprocmask.  Here we do it the quick'n'dirty way by just disabling
+   * interrupts.
+   */
+
+  flags = irqsave();
+  bin->flink = g_unloadhead;
+  g_unloadhead = bin;
+  irqrestore(flags);
+}
+
+/****************************************************************************
+ * Name: unload_list_remove
+ *
+ * Description:
+ *   If CONFIG_SCHED_HAVE_PARENT is defined then schedul_unload() will
+ *   manage instances of struct binary_s allocated with kmalloc.  It
+ *   will keep the binary data in a link list and when SIGCHLD is received
+ *   (meaning that the task has exit'ed, schedul_unload() will find the
+ *   data, unload the module, and free the structure.
+ *
+ *   This function will remove one structure to the linked list
+ *
+ * Input Parameter:
+ *   pid - The task ID of the child task
+ *
+ * Returned Value:
+ *   On success, the load structure is returned.  NULL is returned on
+ *   failure.
+ *
+ ****************************************************************************/
+
+static FAR struct binary_s *unload_list_remove(pid_t pid)
+{
+  FAR struct binary_s *curr;
+  FAR struct binary_s *prev;
+
+  /* Note the asymmetry.  We do not have to disable interrupts here because
+   * the main thread cannot run while we are in the interrupt handler.  Here,
+   * it should be sufficient to disable pre-emption so that no other thread
+   * can run.
+   */
+
+  sched_lock();
+
+  /* Find the structure in the unload list with the matching PID */
+
+  for (prev = NULL, curr = g_unloadhead;
+       curr && (curr->pid != pid);
+       prev = curr, curr = curr->flink);
+
+  /* Did we find it?  It must be there. Hmmm.. we should probably ASSERT if
+   * we do not!
+   */
+
+  if (curr)
+    {
+      /* Was there another entry before this one? */
+
+      if (prev)
+        {
+          /* Yes.. remove the current entry from after the previous entry */
+
+          prev->flink = curr->flink;
+        }
+      else
+        {
+          /* No.. remove the current entry from the head of the list */
+
+          g_unloadhead = curr->flink;
+        }
+
+      /* Nullify the forward link ... superstitious */
+
+      curr->flink = NULL;
+    }
+
+  sched_unlock();
+  return curr;
+}
+
+/****************************************************************************
+ * Name: unload_callback
+ *
+ * Description:
+ *   If CONFIG_SCHED_HAVE_PARENT is defined, this function may be called to
+ *   automatically unload the module when task exits.  It assumes that
+ *   bin was allocated with kmalloc() or friends and will also automatically
+ *   free the structure with kfree() when the task exists.
+ *
+ * Input Parameter:
+ *   pid - The ID of the task that just exited
+ *   arg - A reference to the load structure cast to FAR void *
+ *
+ * Returned Value:
+ *   None
+ *
+ ****************************************************************************/
+
+static void unload_callback(int signo, siginfo_t *info, void *ucontext)
+{
+  FAR struct binary_s *bin;
+  int ret;
+
+  /* Sanity checking */
+
+  if (!info || signo != SIGCHLD)
+    {
+      blldbg("ERROR:Bad signal callback: signo=%d info=%p\n", signo, callback);
+      return;
+    }
+
+  /* Get the load information for this pid */
+
+  bin = unload_list_remove(info->si_pid);
+  if (!bin)
+    {
+      blldbg("ERROR: Could not find load info for PID=%d\n", info->si_pid);
+      return;
+    }
+
+  /* Unload the module */
+
+  ret = unload_module(bin);
+  if (ret < 0)
+    {
+      blldbg("ERROR: unload_module failed: %d\n", get_errno());
+    }
+
+  /* Free the load structure */
+
+  kfree(bin);
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: schedule_unload
+ *
+ * Description:
+ *   If CONFIG_SCHED_HAVE_PARENT is defined, this function may be called by
+ *   the parent of the the newly created task to automatically unload the
+ *   module when the task exits.  This assumes that (1) the caller is the
+ *   parent of the created task, (2) that bin was allocated with kmalloc()
+ *   or friends.  It will also automatically free the structure with kfree()
+ *   after unloading the module.
+ *
+ * Input Parameter:
+ *   pid - The task ID of the child task
+ *   bin - This structure must have been allocated with kmalloc() and must
+ *         persist until the task unloads
+ *
+ * Returned Value:
+ *   This is an end-user function, so it follows the normal convention:
+ *   It returns 0 (OK) if the callback was successfully scheduled. On
+ *   failure, it returns -1 (ERROR) and sets errno appropriately.
+ *
+ *   On failures, the 'bin' structure will not be deallocated and the
+ *   module not not be unloaded.
+ *
+ ****************************************************************************/
+
+int schedule_unload(pid_t pid, FAR struct binary_s *bin)
+{
+  struct sigaction act;
+  struct sigaction oact;
+  sigset_t sigset;
+  irqstate_t flags;
+  int errorcode;
+  int ret;
+
+  /* Make sure that SIGCHLD is unmasked */
+
+  (void)sigemptyset(&sigset);
+  (void)sigaddset(&sigset, SIGCHLD);
+  ret = sigprocmask(SIG_UNBLOCK, &sigset, NULL);
+  if (ret != OK)
+    {
+      /* The errno value will get trashed by the following debug output */
+
+      errorcode = get_errno();
+      bvdbg("ERROR: sigprocmask failed: %d\n", ret);
+      goto errout;
+    }
+
+  /* Add the structure to the list.  We want to do this *before* connecting
+   * the signal handler.  This does, however, make error recovery more
+   * complex if sigaction() fails below because then we have to remove the
+   * unload structure for the list in an unexpected context.
+   */
+
+  unload_list_add(pid, bin);
+
+  /* Register the SIGCHLD handler */
+
+  act.sa_sigaction = unload_callback;
+  act.sa_flags     = SA_SIGINFO;
+
+  (void)sigfillset(&act.sa_mask);
+  (void)sigdelset(&act.sa_mask, SIGCHLD);
+
+  ret = sigaction(SIGCHLD, &act, &oact);
+  if (ret != OK)
+    {
+      /* The errno value will get trashed by the following debug output */
+
+      errorcode = get_errno();
+      bvdbg("ERROR: sigaction failed: %d\n" , ret);
+
+      /* Emergency removal from the list */
+
+      flags = irqsave();
+      if (unload_list_remove(pid) != bin)
+        {
+          blldbg("ERROR: Failed to remove structure\n");
+        }
+      
+      goto errout;
+    }
+
+  return OK;
+
+errout:
+  set_errno(errorcode);
+  return ERROR;
+}
+
+#endif /* !CONFIG_BINFMT_DISABLE && CONFIG_SCHED_HAVE_PARENT */
+
diff --git a/nuttx/binfmt/builtin.c b/nuttx/binfmt/builtin.c
index d36cb6326..e492f72e5 100644
--- a/nuttx/binfmt/builtin.c
+++ b/nuttx/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;
@@ -97,11 +98,11 @@ static int builtin_loadbinary(struct binary_s *binp)
 
   /* Open the binary file for reading (only) */
 
-  fd = open(filename, O_RDONLY);
+  fd = open(binp->filename, O_RDONLY);
   if (fd < 0)
     {
       int errval = errno;
-      bdbg("ERROR: Failed to open binary %s: %d\n", filename, errval);
+      bdbg("ERROR: Failed to open binary %s: %d\n", binp->filename, errval);
       return -errval;
     }
 
@@ -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;
 }
 
diff --git a/nuttx/binfmt/libbuiltin/libbuiltin_getname.c b/nuttx/binfmt/libbuiltin/libbuiltin_getname.c
index 01ac024f7..d1e3958b3 100644
--- a/nuttx/binfmt/libbuiltin/libbuiltin_getname.c
+++ b/nuttx/binfmt/libbuiltin/libbuiltin_getname.c
@@ -83,10 +83,14 @@
 
 FAR const char *builtin_getname(int index)
 {
-  if (index < 0 || index >= number_builtins())
-   {
-     return NULL;
-   }
+  FAR const struct builtin_s *builtin;
 
-  return g_builtins[index].name;
+  builtin = builtin_for_index(index);
+
+  if (builtin != NULL)
+    {
+      return builtin->name;
+    }
+
+  return NULL;
 }
diff --git a/nuttx/binfmt/libbuiltin/libbuiltin_isavail.c b/nuttx/binfmt/libbuiltin/libbuiltin_isavail.c
index f99a4b81d..7a480c0f3 100644
--- a/nuttx/binfmt/libbuiltin/libbuiltin_isavail.c
+++ b/nuttx/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 *name;
   int i;
 
-  for (i = 0; g_builtins[i].name; i++)
+  for (i = 0; (name = builtin_getname(i)); i++)
     {
-      if (!strncmp(g_builtins[i].name, appname, NAME_MAX))
+      if (!strncmp(name, appname, NAME_MAX))
         {
           return i;
         }