sched/signal and syscall/: Add support for pselect() and ppoll() functions

include/nuttx/signal.h

@@ -315,8 +315,6 @@ int nxsig_kill(pid_t pid, int signo);
  *
  ****************************************************************************/
 
-int nxsig_timedwait(FAR const sigset_t *set, FAR struct siginfo *info,
-                    FAR const struct timespec *timeout);
 int nxsig_timedwait(FAR const sigset_t *set, FAR struct siginfo *info,
                     FAR const struct timespec *timeout);
 

include/poll.h

@@ -44,6 +44,7 @@
 #include <nuttx/compiler.h>
 
 #include <stdint.h>
+#include <signal.h>
 #include <semaphore.h>
 
 /****************************************************************************
@@ -153,6 +154,10 @@ extern "C"
 
 int poll(FAR struct pollfd *fds, nfds_t nfds, int timeout);
 
+int ppoll(FAR struct pollfd *fds, nfds_t nfds,
+          FAR const struct timespec *timeout_ts,
+          FAR const sigset_t *sigmask);
+
 #undef EXTERN
 #if defined(__cplusplus)
 }

include/sys/select.h

@@ -43,6 +43,7 @@
 #include <nuttx/config.h>
 
 #include <stdint.h>
+#include <signal.h>
 #include <time.h>
 
 #if CONFIG_NFILE_DESCRIPTORS > 0 || CONFIG_NSOCKET_DESCRIPTORS > 0
@@ -123,6 +124,10 @@ struct timeval;
 int select(int nfds, FAR fd_set *readfds, FAR fd_set *writefds,
            FAR fd_set *exceptfds, FAR struct timeval *timeout);
 
+int pselect(int nfds, FAR fd_set *readfds, FAR fd_set *writefds,
+            FAR fd_set *exceptfds, FAR const struct timespec *timeout,
+            FAR const sigset_t *sigmask);
+
 #undef EXTERN
 #if defined(__cplusplus)
 }

include/sys/syscall.h

@@ -298,7 +298,13 @@
 #  ifndef CONFIG_DISABLE_POLL
 #    define SYS_poll                   __SYS_poll
 #    define SYS_select                 (__SYS_poll + 1)
-#    define __SYS_ifindex              (__SYS_poll + 2)
+#    ifndef CONFIG_DISABLE_SIGNALS
+#      define SYS_ppoll                (__SYS_poll + 2)
+#      define SYS_pselect              (__SYS_poll + 3)
+#      define __SYS_ifindex            (__SYS_poll + 4)
+#    else
+#      define __SYS_ifindex            (__SYS_poll + 2)
+#    endif
 #  else
 #    define __SYS_ifindex               __SYS_poll
 #  endif

sched/signal/Make.defs

@@ -52,6 +52,10 @@ ifeq ($(CONFIG_SIG_EVTHREAD),y)
 CSRCS += sig_evthread.c
 endif
 
+ifneq ($(CONFIG_DISABLE_POLL),y)
+CSRCS += sig_ppoll.c sig_pselect.c
+endif
+
 # Include signal build support
 
 DEPPATH += --dep-path signal

sched/signal/sig_ppoll.c

@@ -0,0 +1,153 @@
+/****************************************************************************
+ * sched/signal/sig_ppoll.c
+ *
+ *   Copyright (C) 2018 Pinecone Inc. All rights reserved.
+ *   Author: Xiang Xiao <xiaoxiang@pinecone.net>
+ *
+ * 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 <poll.h>
+
+#include "sched/sched.h"
+#include "signal/signal.h"
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: ppoll
+ *
+ * Description:
+ *   ppoll() waits for one of a set of file descriptors to become ready to
+ *   perform I/O.  If none of the events requested (and no error) has
+ *   occurred for any of  the  file  descriptors,  then ppoll() blocks until
+ *   one of the events occurs.
+ *
+ * Input Parameters:
+ *   fds  - List of structures describing file descriptors to be monitored
+ *   nfds - The number of entries in the list
+ *   timeout - Specifies an upper limit on the time for which ppoll() will
+ *     block.  A NULL pointer means an infinite timeout.
+ *   sigmask - Replace the current signal mask temporarily during execution
+ *
+ * Returned Value:
+ *   On success, the number of structures that have non-zero revents fields.
+ *   A value of 0 indicates that the call timed out and no file descriptors
+ *   were ready.  On error, -1 is returned, and errno is set appropriately:
+ *
+ *   EBADF  - An invalid file descriptor was given in one of the sets.
+ *   EFAULT - The fds address is invalid
+ *   EINTR  - A signal occurred before any requested event.
+ *   EINVAL - The nfds value exceeds a system limit.
+ *   ENOMEM - There was no space to allocate internal data structures.
+ *   ENOSYS - One or more of the drivers supporting the file descriptor
+ *     does not support the poll method.
+ *
+ ****************************************************************************/
+
+int ppoll(FAR struct pollfd *fds, nfds_t nfds,
+          FAR const struct timespec *timeout_ts,
+          FAR const sigset_t *sigmask)
+{
+  FAR struct tcb_s *rtcb = this_task();
+  sigset_t saved_sigprocmask;
+  irqstate_t flags;
+  int ret = ERROR;
+
+  /* Several operations must be performed below:  We must determine if any
+   * signal is pending and, if not, wait for the signal.  Since signals can
+   * be posted from the interrupt level, there is a race condition that
+   * can only be eliminated by disabling interrupts!
+   */
+
+  flags = enter_critical_section();
+
+  /* Save a copy of the old sigprocmask and install
+   * the new (temporary) sigprocmask
+   */
+
+  saved_sigprocmask = rtcb->sigprocmask;
+  if (sigmask)
+    {
+      rtcb->sigprocmask = *sigmask;
+    }
+
+  rtcb->sigwaitmask = NULL_SIGNAL_SET;
+
+  /* Check if there is a pending signal corresponding to one of the
+   * signals that will be unblocked by the new sigprocmask.
+   */
+
+  if (nxsig_unmask_pendingsignal())
+    {
+      /* Dispatching one or more of the signals is sufficient to cause
+       * us to not wait. Restore the original sigprocmask.
+       */
+
+      rtcb->sigprocmask = saved_sigprocmask;
+      leave_critical_section(flags);
+      set_errno(EINTR);
+    }
+  else
+    {
+      int timeout = -1;
+
+      /* And call poll to do the real work */
+
+      if (timeout_ts)
+      {
+        timeout = timeout_ts->tv_sec * 1000 + timeout_ts->tv_nsec / 1000000;
+      }
+
+      ret = poll(fds, nfds, timeout);
+
+      /* We are running again, restore the original sigprocmask */
+
+      rtcb->sigprocmask = saved_sigprocmask;
+      leave_critical_section(flags);
+
+      /* Now, handle the (rare?) case where (a) a blocked signal was received
+       * while the task was suspended but (b) restoring the original
+       * sigprocmask will unblock the signal.
+       */
+
+      nxsig_unmask_pendingsignal();
+    }
+
+  return ret;
+}
+

sched/signal/sig_pselect.c

@@ -0,0 +1,153 @@
+/****************************************************************************
+ * sched/signal/sig_pselect.c
+ *
+ *   Copyright (C) 2018 Pinecone Inc. All rights reserved.
+ *   Author: Xiang Xiao <xiaoxiang@pinecone.net>
+ *
+ * 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 <sys/select.h>
+#include <sys/time.h>
+
+#include "sched/sched.h"
+#include "signal/signal.h"
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: pselect
+ *
+ * Description:
+ *   pselect() allows a program to monitor multiple file descriptors, waiting
+ *   until one or more of the file descriptors become "ready" for some class
+ *   of I/O operation (e.g., input possible).  A file descriptor is
+ *   considered  ready if it is possible to perform the corresponding I/O
+ *   operation (e.g., read(2)) without blocking.
+ *
+ * Input Parameters:
+ *   nfds - the maximum fd number (+1) of any descriptor in any of the
+ *     three sets.
+ *   readfds - the set of descriptions to monitor for read-ready events
+ *   writefds - the set of descriptions to monitor for write-ready events
+ *   exceptfds - the set of descriptions to monitor for error events
+ *   timeout - Return at this time if none of these events of interest
+ *     occur.
+ *   sigmask - Replace the current signal mask temporarily during execution
+ *
+ *  Returned Value:
+ *   0: Timer expired
+ *  >0: The number of bits set in the three sets of descriptors
+ *  -1: An error occurred (errno will be set appropriately)
+ *
+ ****************************************************************************/
+
+int pselect(int nfds, FAR fd_set *readfds, FAR fd_set *writefds,
+            FAR fd_set *exceptfds, FAR const struct timespec *timeout,
+            FAR const sigset_t *sigmask)
+{
+  FAR struct tcb_s *rtcb = this_task();
+  sigset_t saved_sigprocmask;
+  irqstate_t flags;
+  int ret = ERROR;
+
+  /* Several operations must be performed below:  We must determine if any
+   * signal is pending and, if not, wait for the signal.  Since signals can
+   * be posted from the interrupt level, there is a race condition that
+   * can only be eliminated by disabling interrupts!
+   */
+
+  flags = enter_critical_section();
+
+  /* Save a copy of the old sigprocmask and install
+   * the new (temporary) sigprocmask
+   */
+
+  saved_sigprocmask = rtcb->sigprocmask;
+  if (sigmask)
+    {
+      rtcb->sigprocmask = *sigmask;
+    }
+
+  rtcb->sigwaitmask = NULL_SIGNAL_SET;
+
+  /* Check if there is a pending signal corresponding to one of the
+   * signals that will be unblocked by the new sigprocmask.
+   */
+
+  if (nxsig_unmask_pendingsignal())
+    {
+      /* Dispatching one or more of the signals is sufficient to cause
+       * us to not wait. Restore the original sigprocmask.
+       */
+
+      rtcb->sigprocmask = saved_sigprocmask;
+      leave_critical_section(flags);
+      set_errno(EINTR);
+    }
+  else
+    {
+      FAR struct timeval *timeval = NULL;
+      struct timeval timeval_buf;
+
+      /* And call select to do the real work */
+
+      if (timeout)
+        {
+          timeval_buf.tv_sec  = timeout->tv_sec;
+          timeval_buf.tv_usec = timeout->tv_nsec / 1000;
+          timeval = &timeval_buf;
+        }
+
+      ret = select(nfds, readfds, writefds, exceptfds, timeval);
+
+      /* We are running again, restore the original sigprocmask */
+
+      rtcb->sigprocmask = saved_sigprocmask;
+      leave_critical_section(flags);
+
+      /* Now, handle the (rare?) case where (a) a blocked signal was received
+       * while the task was suspended but (b) restoring the original
+       * sigprocmask will unblock the signal.
+       */
+
+      nxsig_unmask_pendingsignal();
+    }
+
+  return ret;
+}
+

syscall/syscall.csv

@@ -67,8 +67,10 @@
 "pgalloc", "nuttx/arch.h", "defined(CONFIG_BUILD_KERNEL)", "uintptr_t", "uintptr_t", "unsigned int"
 "pipe2","nuttx/drivers/drivers.h","defined(CONFIG_PIPES) && CONFIG_DEV_PIPE_SIZE > 0","int","int [2]|int*","size_t"
 "poll","poll.h","!defined(CONFIG_DISABLE_POLL) && (CONFIG_NSOCKET_DESCRIPTORS > 0 || CONFIG_NFILE_DESCRIPTORS > 0)","int","FAR struct pollfd*","nfds_t","int"
+"ppoll","poll.h","!defined(CONFIG_DISABLE_SIGNALS) && !defined(CONFIG_DISABLE_POLL) && (CONFIG_NSOCKET_DESCRIPTORS > 0 || CONFIG_NFILE_DESCRIPTORS > 0)","int","FAR struct pollfd*","nfds_t","FAR const struct timespec *","FAR const sigset_t *"
 "prctl","sys/prctl.h", "CONFIG_TASK_NAME_SIZE > 0","int","int","..."
 "pread","unistd.h","CONFIG_NSOCKET_DESCRIPTORS > 0 || CONFIG_NFILE_DESCRIPTORS > 0","ssize_t","int","FAR void*","size_t","off_t"
+"pselect","sys/select.h","!defined(CONFIG_DISABLE_SIGNALS) && !defined(CONFIG_DISABLE_POLL) && (CONFIG_NSOCKET_DESCRIPTORS > 0 || CONFIG_NFILE_DESCRIPTORS > 0)","int","int","FAR fd_set*","FAR fd_set*","FAR fd_set*","FAR const struct timespec *","FAR const sigset_t *"
 "pwrite","unistd.h","CONFIG_NSOCKET_DESCRIPTORS > 0 || CONFIG_NFILE_DESCRIPTORS > 0","ssize_t","int","FAR const void*","size_t","off_t"
 "posix_spawnp","spawn.h","!defined(CONFIG_BINFMT_DISABLE) && defined(CONFIG_LIBC_EXECFUNCS) && defined(CONFIG_LIB_ENVPATH)","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 *","FAR char *const []|FAR char *const *"
 "posix_spawn","spawn.h","!defined(CONFIG_BINFMT_DISABLE) && defined(CONFIG_LIBC_EXECFUNCS) && !defined(CONFIG_LIB_ENVPATH)","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 *","FAR char *const []|FAR char *const *"

syscall/syscall_lookup.h

@@ -210,6 +210,8 @@ SYSCALL_LOOKUP(up_assert,                  2, STUB_up_assert)
 #  ifndef CONFIG_DISABLE_POLL
   SYSCALL_LOOKUP(poll,                     3, STUB_poll)
   SYSCALL_LOOKUP(select,                   5, STUB_select)
+  SYSCALL_LOOKUP(ppoll,                    4, STUB_ppoll)
+  SYSCALL_LOOKUP(pselect,                  6, STUB_pselect)
 #  endif
 #  ifdef CONFIG_NETDEV_IFINDEX
   SYSCALL_LOOKUP(if_indextoname,           2, STUB_if_indextoname)

syscall/syscall_stublookup.c

@@ -205,6 +205,11 @@ uintptr_t STUB_poll(int nbr, uintptr_t parm1, uintptr_t parm2,
             uintptr_t parm3);
 uintptr_t STUB_select(int nbr, uintptr_t parm1, uintptr_t parm2,
             uintptr_t parm3, uintptr_t parm4, uintptr_t parm5);
+uintptr_t STUB_ppoll(int nbr, uintptr_t parm1, uintptr_t parm2,
+            uintptr_t parm3, uintptr_t parm4);
+uintptr_t STUB_pselect(int nbr, uintptr_t parm1, uintptr_t parm2,
+            uintptr_t parm3, uintptr_t parm4, uintptr_t parm5,
+            uintptr_t parm6);
 
 /* Asynchronous I/O */