Basic file structure for poll() API

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@1257 42af7a65-404d-4744-a932-0658087f49c3

fs/Makefile

@@ -41,13 +41,13 @@ AOBJS		= $(ASRCS:.S=$(OBJEXT))
 CSRCS		=
 ifeq ($(CONFIG_NFILE_DESCRIPTORS),0)
 ifneq ($(CONFIG_NSOCKET_DESCRIPTORS),0)
-CSRCS		+= fs_close.c fs_write.c fs_ioctl.c
+CSRCS		+= fs_close.c fs_write.c fs_ioctl.c fs_poll.c
 endif
 else
-CSRCS		+= fs_open.c fs_close.c fs_read.c fs_write.c fs_ioctl.c fs_lseek.c \
-		   fs_dup.c fs_mmap.c fs_opendir.c fs_closedir.c fs_stat.c fs_readdir.c \
-		   fs_readdirr.c fs_seekdir.c fs_telldir.c fs_rewinddir.c fs_files.c \
-		   fs_inode.c fs_inodefind.c fs_inodereserve.c fs_statfs.c \
+CSRCS		+= fs_open.c fs_close.c fs_read.c fs_write.c fs_ioctl.c fs_poll.c \
+		   fs_lseek.c fs_dup.c fs_mmap.c fs_opendir.c fs_closedir.c fs_stat.c \
+		   fs_readdir.c fs_readdirr.c fs_seekdir.c fs_telldir.c fs_rewinddir.c \
+		   fs_files.c fs_inode.c fs_inodefind.c fs_inodereserve.c fs_statfs.c \
 		   fs_inoderemove.c fs_registerdriver.c fs_unregisterdriver.c \
 		   fs_inodeaddref.c fs_inoderelease.c
 CSRCS		+= fs_registerblockdriver.c fs_unregisterblockdriver.c \

fs/fs_poll.c

+/****************************************************************************
+ * fs/fs_poll.c
+ *
+ *   Copyright (C) 2008 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * 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/types.h>
+#include <poll.h>
+#include <errno.h>
+
+#include <nuttx/fs.h>
+#include "fs_internal.h"
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: poll
+ *
+ * Description:
+ *   poll() 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  poll() blocks until
+ *   one of the events occurs.
+ *
+ * Inputs:
+ *   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 poll() will
+ *     block in milliseconds.  A negative value of timeout means an infinite
+ *     timeout.
+ *
+ * Return:
+ *   On success, the number of structures that have nonzero 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 poll(FAR struct pollfd *fds, nfds_t nfds, int timeout)
+{
+#ifdef CONFIG_CPP_HAVE_WARNING
+#  warning To be provided
+#endif
+
+  errno = ENOSYS;
+  return ERROR;
+}
+

include/poll.h

+/****************************************************************************
+ * include/poll.h
+ *
+ *   Copyright (C) 2008 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * 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.
+ *
+ ****************************************************************************/
+
+#ifndef __INCLUDE_POLL_H
+#define __INCLUDE_POLL_H
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <semaphore.h>
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/* Poll event definitions:
+ *
+ *   POLLIN
+ *     Data other than high-priority data may be read without blocking.
+ *   POLLRDNORM
+ *     Normal data may be read without blocking.
+ *   POLLRDBAND
+ *     Priority data may be read without blocking.
+ *   POLLPRI
+ *     High priority data may be read without blocking.
+ *   POLLOUT
+ *     Normal data may be written without blocking.
+ *   POLLWRNORM
+ *     Equivalent to POLLOUT.
+ *   POLLWRBAND
+ *     Priority data may be written.
+ *   POLLERR
+ *     An error has occurred (revents only).
+ *   POLLHUP
+ *     Device has been disconnected (revents only).
+ *   POLLNVAL
+ *     Invalid fd member (revents only).
+ */
+
+#define POLLIN       (0x01)  /* NuttX does not make priority distinctions */
+#define POLLRDNORM   (0x01)
+#define POLLRDBAND   (0x01)
+#define POLLPRI      (0x01)
+
+#define POLLOUT      (0x02)  /* NuttX does not make priority distinctions */
+#define POLLWRNORM   (0x02)
+#define POLLWRBAND   (0x02)
+
+#define POLLERR      (0x04)
+#define POLLHUP      (0x08)
+#define POLLNVAL     (0x10)
+
+/****************************************************************************
+ * Public Type Definitions
+ ****************************************************************************/
+
+typedef unsigned int nfds_t;
+
+struct pollfd
+{
+  int    fd;       /* The descriptor being polled */
+  sem_t  *sem;     /* Pointer to semaphore used to post output event */
+  ubyte  events;   /* The input event flags */
+  ubyte  revents;  /* The output event flags */
+};
+
+/****************************************************************************
+ * Public Variables
+ ****************************************************************************/
+
+#undef EXTERN
+#if defined(__cplusplus)
+#define EXTERN extern "C"
+extern "C" {
+#else
+#define EXTERN extern
+#endif
+
+/****************************************************************************
+ * Public Function Prototypes
+ ****************************************************************************/
+
+EXTERN int poll(FAR struct pollfd *fds, nfds_t nfds, int timeout);
+
+#undef EXTERN
+#if defined(__cplusplus)
+}
+#endif
+
+#endif /* __INCLUDE_POLL_H */