libs/libc/unistd: Implement pipe2(2) syscall

See the reference here:
https://www.man7.org/linux/man-pages/man2/pipe2.2.html

Change-Id: Ife19b9bdbde73c7421be381a094da67017819e63
Signed-off-by: chao.an <anchao@xiaomi.com>

drivers/pipes/pipe.c

@@ -186,7 +186,7 @@ static int pipe_close(FAR struct file *filep)
  *
  ****************************************************************************/
 
-int nx_pipe(int fd[2], size_t bufsize)
+int nx_pipe(int fd[2], size_t bufsize, int flags)
 {
   FAR struct pipe_dev_s *dev = NULL;
   char devname[16];
@@ -249,7 +249,7 @@ int nx_pipe(int fd[2], size_t bufsize)
 
   /* Get a write file descriptor */
 
-  fd[1] = nx_open(devname, O_WRONLY);
+  fd[1] = nx_open(devname, O_WRONLY | flags);
   if (fd[1] < 0)
     {
       ret = fd[1];
@@ -258,7 +258,7 @@ int nx_pipe(int fd[2], size_t bufsize)
 
   /* Get a read file descriptor */
 
-  fd[0] = nx_open(devname, O_RDONLY);
+  fd[0] = nx_open(devname, O_RDONLY | flags);
   if (fd[0] < 0)
     {
       ret = fd[0];

drivers/serial/pty.c

@@ -1119,13 +1119,13 @@ int pty_register(int minor)
    *   pipe_b:  Master sink, slave source (RX, master-to-slave)
    */
 
-  ret = nx_pipe(pipe_a, CONFIG_PSEUDOTERM_TXBUFSIZE);
+  ret = nx_pipe(pipe_a, CONFIG_PSEUDOTERM_TXBUFSIZE, 0);
   if (ret < 0)
     {
       goto errout_with_devpair;
     }
 
-  ret = nx_pipe(pipe_b, CONFIG_PSEUDOTERM_RXBUFSIZE);
+  ret = nx_pipe(pipe_b, CONFIG_PSEUDOTERM_RXBUFSIZE, 0);
   if (ret < 0)
     {
       goto errout_with_pipea;

include/nuttx/drivers/drivers.h

@@ -233,6 +233,7 @@ ssize_t bchlib_write(FAR void *handle, FAR const char *buffer, size_t offset,
  *   fd[2] - The user provided array in which to catch the pipe file
  *   descriptors
  *   bufsize - The size of the in-memory, circular buffer in bytes.
+ *   flags - The file status flags.
  *
  * Returned Value:
  *   0 is returned on success; otherwise, the negative error code return
@@ -241,7 +242,7 @@ ssize_t bchlib_write(FAR void *handle, FAR const char *buffer, size_t offset,
  ****************************************************************************/
 
 #if defined(CONFIG_PIPES) && CONFIG_DEV_PIPE_SIZE > 0
-int nx_pipe(int fd[2], size_t bufsize);
+int nx_pipe(int fd[2], size_t bufsize, int flags);
 #endif
 
 /****************************************************************************

include/unistd.h

@@ -343,6 +343,7 @@ FAR void *sbrk(intptr_t incr);
 /* Special devices */
 
 int     pipe(int fd[2]);
+int     pipe2(int pipefd[2], int flags);
 
 /* Schedule an alarm */
 

libs/libc/unistd/Make.defs

@@ -60,7 +60,7 @@ CSRCS += lib_truncate.c
 endif
 
 ifeq ($(CONFIG_PIPES),y)
-CSRCS += lib_pipe.c
+CSRCS += lib_pipe.c lib_pipe2.c
 endif
 
 CSRCS += lib_gethostname.c lib_sethostname.c

libs/libc/unistd/lib_pipe.c

@@ -1,35 +1,20 @@
 /****************************************************************************
  * libs/libc/unistd/lib_pipe.c
  *
- *   Copyright (C) 2016 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <gnutt@nuttx.org>
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
  *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
+ *   http://www.apache.org/licenses/LICENSE-2.0
  *
- * 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.
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
  *
  ****************************************************************************/
 
@@ -72,7 +57,7 @@ int pipe(int fd[2])
 {
   int ret;
 
-  ret = nx_pipe(fd, CONFIG_DEV_PIPE_SIZE);
+  ret = nx_pipe(fd, CONFIG_DEV_PIPE_SIZE, 0);
   if (ret < 0)
     {
       set_errno(-ret);

libs/libc/unistd/lib_pipe2.c

@@ -0,0 +1,71 @@
+/****************************************************************************
+ * libs/libc/unistd/lib_pipe2.c
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.  The
+ * ASF licenses this file to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance with the
+ * License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+ * License for the specific language governing permissions and limitations
+ * under the License.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <errno.h>
+#include <unistd.h>
+
+#include <nuttx/drivers/drivers.h>
+
+#if defined(CONFIG_PIPES) && CONFIG_DEV_PIPE_SIZE > 0
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: pipe2
+ *
+ * Description:
+ *   pipe2() creates a pair of file descriptors, pointing to a pipe inode,
+ *   and  places them in the array pointed to by 'fd'. fd[0] is for reading,
+ *   fd[1] is for writing. If flags is 0, then pipe2() is the same as pipe().
+ *
+ * Input Parameters:
+ *   fd[2] - The user provided array in which to catch the pipe file
+ *   descriptors
+ *   flags - The file status flags.
+ *
+ * Returned Value:
+ *   0 is returned on success; otherwise, -1 is returned with errno set
+ *   appropriately.
+ *
+ ****************************************************************************/
+
+int pipe2(int fd[2], int flags)
+{
+  int ret;
+
+  ret = nx_pipe(fd, CONFIG_DEV_PIPE_SIZE, flags);
+  if (ret < 0)
+    {
+      set_errno(-ret);
+      ret = ERROR;
+    }
+
+  return ret;
+}
+
+#endif /* CONFIG_PIPES && CONFIG_DEV_PIPE_SIZE > 0 */

syscall/syscall.csv

@@ -64,7 +64,7 @@
 "mq_unlink","mqueue.h","!defined(CONFIG_DISABLE_MQUEUE)","int","FAR const char *"
 "munmap","sys/mman.h","defined(CONFIG_FS_RAMMAP)","int","FAR void *","size_t"
 "nx_mkfifo","nuttx/drivers/drivers.h","defined(CONFIG_PIPES) && CONFIG_DEV_FIFO_SIZE > 0","int","FAR const char *","mode_t","size_t"
-"nx_pipe","nuttx/drivers/drivers.h","defined(CONFIG_PIPES) && CONFIG_DEV_PIPE_SIZE > 0","int","int [2]|FAR int *","size_t"
+"nx_pipe","nuttx/drivers/drivers.h","defined(CONFIG_PIPES) && CONFIG_DEV_PIPE_SIZE > 0","int","int [2]|FAR int *","size_t","int"
 "nx_task_spawn","nuttx/spawn.h","defined(CONFIG_LIB_SYSCALL) && !defined(CONFIG_BUILD_KERNEL)","int","FAR const struct spawn_syscall_parms_s *"
 "nx_vsyslog","nuttx/syslog/syslog.h","","int","int","FAR const IPTR char *","FAR va_list *"
 "on_exit","stdlib.h","defined(CONFIG_SCHED_ONEXIT)","int","CODE void (*)(int, FAR void *)","FAR void *"