Add pthread_testcancel(), pthread_testcancel(), and definitiions for cancellation types.

include/nuttx/sched.h

@@ -141,16 +141,18 @@
 #  define TCB_FLAG_TTYPE_PTHREAD   (1 << TCB_FLAG_TTYPE_SHIFT)  /* User pthread */
 #  define TCB_FLAG_TTYPE_KERNEL    (2 << TCB_FLAG_TTYPE_SHIFT)  /* Kernel thread */
 #define TCB_FLAG_NONCANCELABLE     (1 << 2) /* Bit 2: Pthread is non-cancelable */
-#define TCB_FLAG_CANCEL_PENDING    (1 << 3) /* Bit 3: Pthread cancel is pending */
+#define TCB_FLAG_CANCEL_DEFERRED   (1 << 3) /* Bit 3: Deferred (vs asynch) cancellation type */
-#define TCB_FLAG_POLICY_SHIFT      (4) /* Bit 4-5: Scheduling policy */
+#define TCB_FLAG_CANCEL_POINT      (1 << 4) /* Bit 4: At a cancellation point */
+#define TCB_FLAG_CANCEL_PENDING    (1 << 5) /* Bit 5: Pthread cancel is pending */
+#define TCB_FLAG_POLICY_SHIFT      (6) /* Bit 6-7: Scheduling policy */
 #define TCB_FLAG_POLICY_MASK       (3 << TCB_FLAG_POLICY_SHIFT)
 #  define TCB_FLAG_SCHED_FIFO      (0 << TCB_FLAG_POLICY_SHIFT) /* FIFO scheding policy */
 #  define TCB_FLAG_SCHED_RR        (1 << TCB_FLAG_POLICY_SHIFT) /* Round robin scheding policy */
 #  define TCB_FLAG_SCHED_SPORADIC  (2 << TCB_FLAG_POLICY_SHIFT) /* Sporadic scheding policy */
 #  define TCB_FLAG_SCHED_OTHER     (3 << TCB_FLAG_POLICY_SHIFT) /* Other scheding policy */
-#define TCB_FLAG_CPU_LOCKED        (1 << 6) /* Bit 6: Locked to this CPU */
+#define TCB_FLAG_CPU_LOCKED        (1 << 8) /* Bit 8: Locked to this CPU */
-#define TCB_FLAG_EXIT_PROCESSING   (1 << 7) /* Bit 7: Exitting */
+#define TCB_FLAG_EXIT_PROCESSING   (1 << 9) /* Bit 9: Exitting */
-                                            /* Bits 8-15: Available */
+                                            /* Bits 10-15: Available */
 
 /* Values for struct task_group tg_flags */
 

include/pthread.h

@@ -115,11 +115,16 @@
 
 #define PTHREAD_DEFAULT_PRIORITY      100
 
-/* Cancellation states returned by pthread_cancelstate() */
+/* Cancellation states used by pthread_setcancelstate() */
 
 #define PTHREAD_CANCEL_ENABLE         (0)
 #define PTHREAD_CANCEL_DISABLE        (1)
 
+/* Cancellation types used by pthread_setcanceltype() */
+
+#define PTHREAD_CANCEL_DEFERRED       (0)
+#define PTHREAD_CANCEL_ASYNCHRONOUS   (1)
+
 /* Thread return value when a pthread is canceled */
 
 #define PTHREAD_CANCELED              ((FAR void*)ERROR)
@@ -340,6 +345,7 @@ int pthread_detach(pthread_t thread);
 void pthread_exit(pthread_addr_t value) noreturn_function;
 int  pthread_cancel(pthread_t thread);
 int  pthread_setcancelstate(int state, FAR int *oldstate);
+int  pthread_setcanceltype(int type, FAR int *oldtype);
 void pthread_testcancel(void);
 
 /* A thread may set up cleanup functions to execut when the thread exits or

sched/Kconfig

@@ -560,6 +560,15 @@ config PTHREAD_CLEANUP_STACKSIZE
 
 endmenu # Pthread Options
 
+config CANCELLATION_POINTS
+	bool "Cancellation points"
+	default n
+	depends on EXPERIMENTAL
+	---help---
+		Enable POSIX cancellation points for pthread_cancel().  If selected,
+		cancellation points will also used with the () task_delete() API even if
+		pthreads are not enabled.
+
 menu "Performance Monitoring"
 
 config SCHED_CPULOAD

sched/pthread/Make.defs

@@ -42,7 +42,8 @@ CSRCS += pthread_mutexlock.c pthread_mutextrylock.c pthread_mutexunlock.c
 CSRCS += pthread_condinit.c pthread_conddestroy.c
 CSRCS += pthread_condwait.c pthread_condsignal.c pthread_condbroadcast.c
 CSRCS += pthread_barrierinit.c pthread_barrierdestroy.c pthread_barrierwait.c
-CSRCS += pthread_cancel.c pthread_setcancelstate.c
+CSRCS += pthread_cancel.c pthread_setcancelstate.c  pthread_setcanceltype.c
+CSRCS += pthread_testcancel.c
 CSRCS += pthread_keycreate.c pthread_setspecific.c pthread_getspecific.c pthread_keydelete.c
 CSRCS += pthread_initialize.c pthread_completejoin.c pthread_findjoininfo.c
 CSRCS += pthread_once.c pthread_release.c pthread_setschedprio.c

sched/pthread/pthread_cleanup.c

@@ -67,6 +67,9 @@
  * Return Value:
  *   None
  *
+ * Assumptions:
+ *   The scheduler is locked.
+ *
  ****************************************************************************/
 
 static void pthread_cleanup_pop_tcb(FAR struct pthread_tcb_s *tcb, int execute)

sched/pthread/pthread_create.c

@@ -483,6 +483,12 @@ int pthread_create(FAR pthread_t *thread, FAR const pthread_attr_t *attr,
 #endif
     }
 
+#ifdef CONFIG_CANCELLATION_POINTS
+  /* Set the deferred cancellation type */
+
+  ptcb->cmn.flags |= TCB_FLAG_CANCEL_DEFERRED;
+#endif
+
   /* Get the assigned pid before we start the task (who knows what
    * could happen to ptcb after this!).  Copy this ID into the join structure
    * as well.

sched/pthread/pthread_setcancelstate.c

@@ -47,6 +47,18 @@
 
 /****************************************************************************
  * Name: pthread_setcancelstate
+ *
+ * Description:
+ *   The pthread_setcancelstate() function atomically both sets the calling
+ *   thread's cancelability state to the indicated state and returns the
+ *   previous cancelability state at the location referenced by oldstate.
+ *   Legal values for state are PTHREAD_CANCEL_ENABLE and
+ *   PTHREAD_CANCEL_DISABLE.
+ *
+ *   The cancelability state and type of any newly created threads,
+ *   including the thread in which main() was first invoked, are
+ *   PTHREAD_CANCEL_ENABLE and PTHREAD_CANCEL_DEFERRED respectively.
+ *
  ****************************************************************************/
 
 int pthread_setcancelstate(int state, FAR int *oldstate)
@@ -78,17 +90,38 @@ int pthread_setcancelstate(int state, FAR int *oldstate)
 
   if (state == PTHREAD_CANCEL_ENABLE)
     {
-      unsigned flags = tcb->flags;
+      /* Clear the non-cancelable flag */
 
-      /* Clear the non-cancelable and cancel pending flags */
+      tcb->flags &= ~TCB_FLAG_NONCANCELABLE;
 
-      tcb->flags &= ~(TCB_FLAG_NONCANCELABLE | TCB_FLAG_CANCEL_PENDING);
+      /* Check if a cancellation was pending */
 
-      /* If the cancel was pending, then just exit as requested */
+      if ((tcb->flags & TCB_FLAG_CANCEL_PENDING) != 0)
-
-      if (flags & TCB_FLAG_CANCEL_PENDING)
         {
-          pthread_exit(PTHREAD_CANCELED);
+#ifdef CONFIG_CANCELLATION_POINTS
+          /* If we are using deferred cancellation? */
+
+          if ((tcb->flags & TCB_FLAG_CANCEL_DEFERRED) != 0)
+            {
+              /* Yes.. If we are within a cancellation point, then
+               * notify of the cancellation.
+               */
+
+              if (tcb->flags & TCB_FLAG_CANCEL_POINT) != 0)
+                {
+#  warning Missing logic
+                }
+            }
+          else
+#endif
+           {
+             /* No.. We are using asynchronous cancellation.  If the
+              * cancellation was pending in this case, then just exit.
+              */
+
+             tcb->flags &= ~TCB_FLAG_CANCEL_PENDING;
+             pthread_exit(PTHREAD_CANCELED);
+           }
         }
     }
   else if (state == PTHREAD_CANCEL_DISABLE)

sched/pthread/pthread_setcanceltype.c

@@ -0,0 +1,128 @@
+/****************************************************************************
+ * sched/pthread/pthread_setcanceltype.c
+ *
+ *   Copyright (C) 2016 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 <pthread.h>
+#include <errno.h>
+
+#include "sched/sched.h"
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: pthread_setcancelstate
+ *
+ * Description:
+ *   The pthread_setcanceltype() function atomically both sets the calling
+ *   thread's cancelability type to the indicated type and returns the
+ *   previous cancelability type at the location referenced by oldtype
+ *   Legal values for type are PTHREAD_CANCEL_DEFERRED and
+ *   PTHREAD_CANCEL_ASYNCHRONOUS.
+ *
+ *   The cancelability state and type of any newly created threads,
+ *   including the thread in which main() was first invoked, are
+ *   PTHREAD_CANCEL_ASYNCHRONOUS and PTHREAD_CANCEL_DEFERRED respectively.
+ *
+ ****************************************************************************/
+
+int pthread_setcanceltype(int type, FAR int *oldtype)
+{
+  FAR struct tcb_s *tcb = this_task();
+  int ret = OK;
+
+  /* Suppress context changes for a bit so that the flags are stable. (the
+   * flags should not change in interrupt handling).
+   */
+
+  sched_lock();
+
+  /* Return the current type if so requrested */
+
+  if (oldtype)
+    {
+      if ((tcb->flags & TCB_FLAG_CANCEL_DEFERRED) != 0)
+        {
+          *oldtype = PTHREAD_CANCEL_DEFERRED;
+        }
+      else
+        {
+          *oldtype = PTHREAD_CANCEL_ASYNCHRONOUS;
+        }
+    }
+
+  /* Set the new cancellation type */
+
+  if (type == PTHREAD_CANCEL_ASYNCHRONOUS)
+    {
+      /* Clear the deferred cancellation bit */
+
+      tcb->flags &= ~TCB_FLAG_CANCEL_DEFERRED;
+
+#ifdef CONFIG_CANCELLATION_POINTS
+      /* If we just switched from deferred to asynchronous type and if a
+       * cancellation is pending, then exit now.
+       */
+
+      if ((tcb->flags & TCB_FLAG_CANCEL_PENDING) != 0 &&
+          (tcb->flags & TCB_FLAG_NONCANCELABLE) == 0)
+        {
+          tcb->flags &= ~TCB_FLAG_CANCEL_PENDING;
+          pthread_exit(PTHREAD_CANCELED);
+        }
+#endif
+    }
+#ifdef CONFIG_CANCELLATION_POINTS
+  else if (type == PTHREAD_CANCEL_DEFERRED)
+    {
+      /* Set the deferred cancellation type */
+
+      tcb->flags |= TCB_FLAG_CANCEL_DEFERRED;
+    }
+#endif
+  else
+    {
+      ret = EINVAL;
+    }
+
+  sched_unlock();
+  return ret;
+}

sched/pthread/pthread_testcancel.c

@@ -0,0 +1,66 @@
+/****************************************************************************
+ * sched/pthread/pthread_testcancel.c
+ *
+ *   Copyright (C) 2016 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 <pthread.h>
+#include <errno.h>
+
+#include "sched/sched.h"
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: pthread_testcancel
+ *
+ * Description:
+ *   The pthread_testcancel() function creates a cancellation point in the
+ *   calling thread. The pthread_testcancel() function has no effect if
+ *   cancelability is disabled
+ *
+ ****************************************************************************/
+
+void pthread_testcancel(void)
+{
+#ifdef CONFIG_CANCELLATION_POINTS
+#  warning Missing Logic
+#endif
+}

sched/task/task_setup.c

@@ -378,6 +378,12 @@ static int thread_schedsetup(FAR struct tcb_s *tcb, int priority,
       tcb->flags         &= ~TCB_FLAG_TTYPE_MASK;
       tcb->flags         |= ttype;
 
+#ifdef CONFIG_CANCELLATION_POINTS
+      /* Set the deferred cancellation type */
+
+      tcb->flags         |= TCB_FLAG_CANCEL_DEFERRED;
+#endif
+
       /* Save the task ID of the parent task in the TCB and allocate
        * a child status structure.
        */