Add internal API task_reparent(), used in posix_spawn(). Move libc/spawn/lib_ps.c to sched/task_posixspawn.c; Move libc/spawn/spawn.h to include/nuttx/spawn.h

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@5531 42af7a65-404d-4744-a932-0658087f49c3

16 files changed, 235 insertions, 42 deletions

diff --git a/nuttx/ChangeLog b/nuttx/ChangeLog
index 1b0c5338b..2a1561abe 100644
--- a/nuttx/ChangeLog
+++ b/nuttx/ChangeLog
@@ -3971,4 +3971,9 @@
 	  automatically unload and clean-up after running a task that
 	  was loaded into memory.
 	* binfmt/libbuiltin: Extensions from Mike Smith
-
+	* sched/task_reparent.c:  Add internal interface to change the
+	  parent task.
+	* sched/task_posixspawn():  Move libc/spawn/lib_ps.c to
+	  sched/task_posixspawn() now it requires internal, reparenting
+	  interfaces
+	* include/nuttx/spawn():  Move libc/spawn.h to include/nuttx/spawn.h
diff --git a/nuttx/binfmt/binfmt_exec.c b/nuttx/binfmt/binfmt_exec.c
index 7f45fb841..4226b6cfc 100644
--- a/nuttx/binfmt/binfmt_exec.c
+++ b/nuttx/binfmt/binfmt_exec.c
@@ -97,7 +97,6 @@ int exec(FAR const char *filename, FAR const char **argv,
 {
 #ifdef CONFIG_SCHED_ONEXIT
   FAR struct binary_s *bin;
-  int errorcode;
   int pid;
   int ret;
 
diff --git a/nuttx/libc/spawn/spawn.h b/nuttx/include/nuttx/spawn.h
index 3f4e195cc..f84ae8355 100644
--- a/nuttx/libc/spawn/spawn.h
+++ b/nuttx/include/nuttx/spawn.h
@@ -1,5 +1,5 @@
 /****************************************************************************
- * libc/spawn/spawn.h
+ * include/nuttx/spawn.h
  *
  *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
@@ -33,8 +33,8 @@
  *
  ****************************************************************************/
 
-#ifndef __LIBC_SPAWN_SPAWN_H
-#define __LIBC_SPAWN_SPAWN_H
+#ifndef __INCLUDE_NUTTX_SPAWN_H
+#define __INCLUDE_NUTTX_SPAWN_H
 
 /****************************************************************************
  * Included Files
@@ -118,4 +118,4 @@ void add_file_action(FAR posix_spawn_file_actions_t *file_action,
 }
 #endif
 
-#endif /* __LIBC_SPAWN_SPAWN_H */
+#endif /* __INCLUDE_NUTTX_SPAWN_H */
diff --git a/nuttx/include/signal.h b/nuttx/include/signal.h
index 30726105b..7c6b4cd55 100644
--- a/nuttx/include/signal.h
+++ b/nuttx/include/signal.h
@@ -61,14 +61,17 @@
 
 /* All signals are "real time" signals */
 
-#define SIGRTMIN        0  /* First real time signal */
-#define SIGRTMAX        31 /* Last real time signal */
+#define SIGRTMIN        MIN_SIGNO  /* First real time signal */
+#define SIGRTMAX        MAX_SIGNO  /* Last real time signal */
 
 /* A few of the real time signals are used within the OS.  They have
  * default values that can be overridden from the configuration file. The
  * rest are all user signals.
  *
- * These are semi-standard signal definitions:
+ * The signal number zero is wasted for the most part.  It is a valid
+ * signal number, but has special meaning at many interfaces (e.g., Kill()).
+ *
+ * These are the semi-standard signal definitions:
  */
 
 #ifndef CONFIG_SIG_SIGUSR1
diff --git a/nuttx/libc/spawn/Make.defs b/nuttx/libc/spawn/Make.defs
index 99ee781ce..8cb086fee 100644
--- a/nuttx/libc/spawn/Make.defs
+++ b/nuttx/libc/spawn/Make.defs
@@ -37,8 +37,6 @@
 
 ifeq ($(CONFIG_LIBC_EXECFUNCS),y)
 
-CSRCS += lib_ps.c
-
 CSRCS += lib_psfa_addaction.c lib_psfa_addclose.c lib_psfa_adddup2.c
 CSRCS += lib_psfa_addopen.c lib_psfa_destroy.c lib_psfa_init.c
 
diff --git a/nuttx/libc/spawn/lib_psfa_addaction.c b/nuttx/libc/spawn/lib_psfa_addaction.c
index 3f297d7cf..8700efc2a 100644
--- a/nuttx/libc/spawn/lib_psfa_addaction.c
+++ b/nuttx/libc/spawn/lib_psfa_addaction.c
@@ -41,7 +41,7 @@
 
 #include <spawn.h>
 
-#include "spawn/spawn.h"
+#include <nuttx/spawn.h>
 
 /****************************************************************************
  * Global Functions
diff --git a/nuttx/libc/spawn/lib_psfa_addclose.c b/nuttx/libc/spawn/lib_psfa_addclose.c
index bf22a153a..1c72f0f82 100644
--- a/nuttx/libc/spawn/lib_psfa_addclose.c
+++ b/nuttx/libc/spawn/lib_psfa_addclose.c
@@ -44,7 +44,7 @@
 #include <assert.h>
 #include <errno.h>
 
-#include "spawn/spawn.h"
+#include <nuttx/spawn.h>
 
 /****************************************************************************
  * Global Functions
diff --git a/nuttx/libc/spawn/lib_psfa_adddup2.c b/nuttx/libc/spawn/lib_psfa_adddup2.c
index fc788a4e9..deb3cbdb3 100644
--- a/nuttx/libc/spawn/lib_psfa_adddup2.c
+++ b/nuttx/libc/spawn/lib_psfa_adddup2.c
@@ -44,7 +44,7 @@
 #include <assert.h>
 #include <errno.h>
 
-#include "spawn/spawn.h"
+#include <nuttx/spawn.h>
 
 /****************************************************************************
  * Global Functions
diff --git a/nuttx/libc/spawn/lib_psfa_addopen.c b/nuttx/libc/spawn/lib_psfa_addopen.c
index 385e1cfc3..66bbd813a 100644
--- a/nuttx/libc/spawn/lib_psfa_addopen.c
+++ b/nuttx/libc/spawn/lib_psfa_addopen.c
@@ -45,7 +45,7 @@
 #include <assert.h>
 #include <errno.h>
 
-#include "spawn/spawn.h"
+#include <nuttx/spawn.h>
 
 /****************************************************************************
  * Global Functions
diff --git a/nuttx/libc/spawn/lib_psfa_destroy.c b/nuttx/libc/spawn/lib_psfa_destroy.c
index 5d0a644d8..a21886645 100644
--- a/nuttx/libc/spawn/lib_psfa_destroy.c
+++ b/nuttx/libc/spawn/lib_psfa_destroy.c
@@ -43,7 +43,7 @@
 #include <spawn.h>
 #include <assert.h>
 
-#include "spawn/spawn.h"
+#include <nuttx/spawn.h>
 
 /****************************************************************************
  * Global Functions
diff --git a/nuttx/libc/spawn/lib_psfa_dump.c b/nuttx/libc/spawn/lib_psfa_dump.c
index d7bf1576d..0dbaeb023 100644
--- a/nuttx/libc/spawn/lib_psfa_dump.c
+++ b/nuttx/libc/spawn/lib_psfa_dump.c
@@ -43,7 +43,7 @@
 #include <assert.h>
 #include <debug.h>
 
-#include "spawn/spawn.h"
+#include <nuttx/spawn.h>
 
 #ifdef CONFIG_DEBUG
 
diff --git a/nuttx/sched/Makefile b/nuttx/sched/Makefile
index 3d6b58bac..73c67239e 100644
--- a/nuttx/sched/Makefile
+++ b/nuttx/sched/Makefile
@@ -48,7 +48,7 @@ TSK_SRCS	= prctl.c task_create.c task_init.c task_setup.c task_activate.c \
 		  task_restart.c task_vfork.c exit.c getpid.c sched_addreadytorun.c \
 		  sched_removereadytorun.c sched_addprioritized.c sched_mergepending.c \
 		  sched_addblocked.c sched_removeblocked.c sched_free.c sched_gettcb.c \
-		  sched_verifytcb.c sched_releasetcb.c
+		  sched_verifytcb.c sched_releasetcb.c task_posixspawn.c
 
 SCHED_SRCS	= sched_setparam.c sched_setpriority.c sched_getparam.c \
 		  sched_setscheduler.c sched_getscheduler.c \
@@ -67,6 +67,10 @@ ifeq ($(CONFIG_PRIORITY_INHERITANCE),y)
 SCHED_SRCS	+= sched_reprioritize.c 
 endif
 
+ifeq ($(CONFIG_SCHED_HAVE_PARENT),y)
+SCHED_SRCS	+= task_reparent.c 
+endif
+
 ifeq ($(CONFIG_SCHED_WAITPID),y)
 SCHED_SRCS	+= sched_waitpid.c
 ifeq ($(CONFIG_SCHED_HAVE_PARENT),y)
diff --git a/nuttx/sched/os_internal.h b/nuttx/sched/os_internal.h
index 32d9fb4ac..f21d9654f 100644
--- a/nuttx/sched/os_internal.h
+++ b/nuttx/sched/os_internal.h
@@ -268,6 +268,9 @@ int  task_schedsetup(FAR _TCB *tcb, int priority, start_t start,
 int  task_argsetup(FAR _TCB *tcb, FAR const char *name, FAR const char *argv[]);
 void task_exithook(FAR _TCB *tcb, int status);
 int  task_deletecurrent(void);
+#ifdef CONFIG_SCHED_HAVE_PARENT
+int  task_reparent(pid_t oldpid, pid_t newpid, pid_t chpid);
+#endif
 #ifndef CONFIG_CUSTOM_STACK
 int  kernel_thread(FAR const char *name, int priority, int stack_size,
                    main_t entry, FAR const char *argv[]);
diff --git a/nuttx/libc/spawn/lib_ps.c b/nuttx/sched/task_posixspawn.c
index 1bf7c2113..4201e759b 100644
--- a/nuttx/libc/spawn/lib_ps.c
+++ b/nuttx/sched/task_posixspawn.c
@@ -1,5 +1,5 @@
 /****************************************************************************
- * libc/string/lib_ps.c
+ * sched/task_posixspawn.c
  *
  *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
@@ -50,8 +50,9 @@
 #include <debug.h>
 
 #include <nuttx/binfmt/binfmt.h>
+#include <nuttx/spawn.h>
 
-#include "spawn/spawn.h"
+#include "os_internal.h"
 
 /****************************************************************************
  * Private Types
@@ -86,7 +87,7 @@ static struct spawn_parms_s g_ps_parms;
  ****************************************************************************/
 
 /****************************************************************************
- * Name: ps_semtake and ps_semgive
+ * Name: spawn_semtake and spawn_semgive
  *
  * Description:
  *   Give and take semaphores
@@ -100,7 +101,7 @@ static struct spawn_parms_s g_ps_parms;
  *
  ****************************************************************************/
 
-static void ps_semtake(FAR sem_t *sem)
+static void spawn_semtake(FAR sem_t *sem)
 {
   int ret;
 
@@ -112,10 +113,10 @@ static void ps_semtake(FAR sem_t *sem)
   while (ret != 0);
 }
 
-#define ps_semgive(sem) sem_post(sem)
+#define spawn_semgive(sem) sem_post(sem)
 
 /****************************************************************************
- * Name: ps_exec
+ * Name: spawn_exec
  *
  * Description:
  *   Execute the task from the file system.
@@ -153,9 +154,9 @@ static void ps_semtake(FAR sem_t *sem)
  *
  ****************************************************************************/
 
-static int ps_exec(FAR pid_t *pidp, FAR const char *path,
-                   FAR const posix_spawnattr_t *attr,
-                   FAR char *const argv[])
+static int spawn_exec(FAR pid_t *pidp, FAR const char *path,
+                      FAR const posix_spawnattr_t *attr,
+                      FAR char *const argv[])
 {
   struct sched_param param;
   FAR const struct symtab_s *symtab;
@@ -420,7 +421,23 @@ static int spawn_proxy(int argc, char *argv[])
     {
       /* Start the task */
 
-      ret = ps_exec(g_ps_parms.pid, g_ps_parms.path, attr, g_ps_parms.argv);
+      ret = spawn_exec(g_ps_parms.pid, g_ps_parms.path, attr,
+                       g_ps_parms.argv);
+
+#ifdef CONFIG_SCHED_HAVE_PARENT
+      if (ret == OK)
+        {
+          /* Change of the parent of the task we just spawned to our parent.
+           * What should we do in the event of a failure?
+           */
+
+          int tmp = task_reparent(0, 0, *g_ps_parms.pid);
+          if (tmp < 0)
+            {
+              sdbg("ERROR: task_reparent() failed: %d\n", tmp);
+            }
+        }
+#endif
     }
 
   /* Post the semaphore to inform the parent task that we have completed
@@ -429,9 +446,9 @@ static int spawn_proxy(int argc, char *argv[])
 
   g_ps_parms.result = ret;
 #ifndef CONFIG_SCHED_WAITPID
-  ps_semgive(&g_ps_execsem);
+  spawn_semgive(&g_ps_execsem);
 #endif
-  return 0;
+  return OK;
 }
 
 /****************************************************************************
@@ -566,7 +583,7 @@ int posix_spawn(FAR pid_t *pid, FAR const char *path,
   if (file_actions ==  NULL || *file_actions == NULL)
 #endif
     {
-      return ps_exec(pid, path, attr, argv);
+      return spawn_exec(pid, path, attr, argv);
     }
 
   /* Otherwise, we will have to go through an intermediary/proxy task in order
@@ -582,7 +599,7 @@ int posix_spawn(FAR pid_t *pid, FAR const char *path,
 
   /* Get exclusive access to the global parameter structure */
 
-  ps_semtake(&g_ps_parmsem);
+  spawn_semtake(&g_ps_parmsem);
 
   /* Populate the parameter structure */
 
@@ -601,22 +618,33 @@ int posix_spawn(FAR pid_t *pid, FAR const char *path,
       int errcode = errno;
 
       sdbg("ERROR: sched_getparam failed: %d\n", errcode);
-      ps_semgive(&g_ps_parmsem);
+      spawn_semgive(&g_ps_parmsem);
       return errcode;
     }
 
-  /* Start the intermediary/proxy task at the same priority as the parent task. */
+  /* Disable pre-emption so that the proxy does not run until we waitpid
+   * is called.  This is probably unnecessary since the spawn_proxy has
+   * the same priority as this thread; it should be schedule behind this
+   * task in the ready-to-run list.
+   */
+
+#ifdef CONFIG_SCHED_WAITPID
+  sched_lock();
+#endif
+
+  /* Start the intermediary/proxy task at the same priority as the parent
+   * task.
+   */
 
   proxy = TASK_CREATE("spawn_proxy", param.sched_priority,
                       CONFIG_POSIX_SPAWN_STACKSIZE, (main_t)spawn_proxy,
                       (FAR const char **)NULL);
   if (proxy < 0)
     {
-      int errcode = errno;
+      ret = get_errno();
+      sdbg("ERROR: Failed to start spawn_proxy: %d\n", ret);
 
-      sdbg("ERROR: Failed to start spawn_proxy: %d\n", errcode);
-      ps_semgive(&g_ps_parmsem);
-      return errcode;
+      goto errout_with_lock;
     }
 
    /* Wait for the proxy to complete its job */
@@ -625,15 +653,21 @@ int posix_spawn(FAR pid_t *pid, FAR const char *path,
    ret = waitpid(proxy, &status, 0);
    if (ret < 0)
      {
-      sdbg("ERROR: waitpid() failed: %d\n", errno);
+       sdbg("ERROR: waitpid() failed: %d\n", errno);
+       goto errout_with_lock;
      }
 #else
-   ps_semtake(&g_ps_execsem);
+   spawn_semtake(&g_ps_execsem);
 #endif
 
    /* Get the result and relinquish our access to the parameter structure */
 
    ret = g_ps_parms.result;
-   ps_semgive(&g_ps_parmsem);
-   return ret;
+
+errout_with_lock:
+#ifdef CONFIG_SCHED_WAITPID
+  sched_unlock();
+#endif
+  spawn_semgive(&g_ps_parmsem);
+  return ret;
 }
diff --git a/nuttx/sched/task_reparent.c b/nuttx/sched/task_reparent.c
new file mode 100644
index 000000000..9daa0743b
--- /dev/null
+++ b/nuttx/sched/task_reparent.c
@@ -0,0 +1,145 @@
+/*****************************************************************************
+ * sched/task_reparent.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 <errno.h>
+
+#include "os_internal.h"
+
+#ifdef CONFIG_SCHED_HAVE_PARENT
+
+/*****************************************************************************
+ * Private Functions
+ *****************************************************************************/
+
+/*****************************************************************************
+ * Public Functions
+ *****************************************************************************/
+
+/*****************************************************************************
+ * Name: task_reparent
+ *
+ * Description:
+ *   Change the parent of a task.
+ *
+ * Parameters:
+ *   oldpid - PID of the old parent task (0 if this task)
+ *   newpid - PID ot the new parent task (0 for the parent of this task)
+ *   chpid  - PID of the child to be reparented.
+ *
+ * Return Value:
+ *   0 (OK) on success; A negated errno value on failure.
+ *
+ *****************************************************************************/
+
+int task_reparent(pid_t oldpid, pid_t newpid, pid_t chpid)
+{
+  _TCB *oldtcb;
+  _TCB *newtcb;
+  _TCB *chtcb;
+  irqstate_t flags;
+  int ret;
+
+  /* If oldpid is zero, then we are parent task. */
+
+  if (oldpid == 0)
+    {
+      oldpid = getpid();
+    }
+
+  /* Get the current parent task's TCB */
+
+  oldtcb = sched_gettcb(oldpid);
+  if (!oldtcb)
+    {
+      return -ESRCH;
+    }
+
+  /* Disable interrupts so that nothing can change from this point */
+
+  flags = irqsave();
+
+  /* If newpid is zero, then new is the parent of oldpid. */
+
+  if (newpid == 0)
+    {
+      newpid = oldtcb->parent;
+    }
+  
+  /* Get the new parent task's TCB */
+
+  newtcb = sched_gettcb(newpid);
+  if (!newtcb)
+    {
+      ret = -ESRCH;
+      goto errout_with_ints;
+    }
+
+  /* Get the child tasks TCB */
+
+  chtcb = sched_gettcb(chpid);
+  if (!chtcb)
+    {
+      ret = -ECHILD;
+      goto errout_with_ints;
+    }
+
+  /* Verify that oldpid is the parent of chpid */
+
+  if (chtcb->parent != oldpid)
+    {
+      ret = -ECHILD;
+      goto errout_with_ints;
+    }
+
+  /* Okay, reparent the child */
+
+  DEBUGASSERT(oldtcb->nchildren > 0);
+  chtcb->parent = newpid;
+  oldtcb->nchildren--;
+  newtcb->nchildren++;
+  ret = OK;
+  
+errout_with_ints:
+  irqrestore(flags);
+  return ret;  
+}
+
+#endif /* CONFIG_SCHED_HAVE_PARENT */
diff --git a/nuttx/syscall/syscall.csv b/nuttx/syscall/syscall.csv
index 4ccd53f9d..5bc52a71d 100644
--- a/nuttx/syscall/syscall.csv
+++ b/nuttx/syscall/syscall.csv
@@ -43,6 +43,8 @@
 "prctl","sys/prctl.h", "CONFIG_TASK_NAME_SIZE > 0","int","int","..." 
 "clock_systimer","nuttx/clock.h","!defined(CONFIG_DISABLE_CLOCK)","uint32_t"
 "poll","poll.h","!defined(CONFIG_DISABLE_POLL) && (CONFIG_NSOCKET_DESCRIPTORS > 0 || CONFIG_NFILE_DESCRIPTORS > 0)","int","FAR struct pollfd*","nfds_t","int"
+"posix_spawnp", defined(CONFIG_BINFMT_EXEPATH), "int","FAR pid_t *","FAR const char *","FAR const posix_spawn_file_actions_t *","FAR const posix_spawnattr_t *","FAR char *const []","FAR char *const []"
+"posix_spawn", !defined(CONFIG_BINFMT_EXEPATH), "int","FAR pid_t *","FAR const char *","FAR const posix_spawn_file_actions_t *","FAR const posix_spawnattr_t *","FAR char *const []","FAR char *const []"
 "pthread_barrier_destroy","pthread.h","!defined(CONFIG_DISABLE_PTHREAD)","int","FAR pthread_barrier_t*"
 "pthread_barrier_init","pthread.h","!defined(CONFIG_DISABLE_PTHREAD)","int","FAR pthread_barrier_t*","FAR const pthread_barrierattr_t*","unsigned int"
 "pthread_barrier_wait","pthread.h","!defined(CONFIG_DISABLE_PTHREAD)","int","FAR pthread_barrier_t*"