[libc] Adjust libc.

1. Move struct stat to libc_stat.h;
2. Defined a new FD_SET macros in libc_fdset.h.

components/dfs/include/dfs.h

@@ -80,15 +80,6 @@
 extern "C" {
 #endif
 
-struct stat
-{
-    struct rt_device* st_dev;
-    uint16_t st_mode;
-    uint32_t st_size;
-    time_t   st_mtime;
-    uint32_t st_blksize;
-};
-
 struct statfs
 {
     size_t f_bsize;   /* block size */

components/dfs/include/dfs_select.h

 #ifndef DFS_SELECT_H__
 #define DFS_SELECT_H__
 
-#ifdef RT_USING_LWIP
-/* we use lwIP's structure definitions. */
-#include <lwip/sockets.h>
-#elif defined(RT_USING_POSIX)
+#include <libc/libc_fdset.h>
 
-#ifndef FD_SET
-
-/* Get the total number of descriptors that we will have to support */
-
-#define FD_SETSIZE (12)
-
-/* We will use a 32-bit bitsets to represent the set of descriptors.  How
- * many uint32_t's do we need to span all descriptors?
- */
-
-#if FD_SETSIZE <= 32
-#  define __SELECT_NUINT32 1
-#elif FD_SETSIZE <= 64
-#  define __SELECT_NUINT32 2
-#elif FD_SETSIZE <= 96
-#  define __SELECT_NUINT32 3
-#elif FD_SETSIZE <= 128
-#  define __SELECT_NUINT32 4
-#elif FD_SETSIZE <= 160
-#  define __SELECT_NUINT32 5
-#elif FD_SETSIZE <= 192
-#  define __SELECT_NUINT32 6
-#elif FD_SETSIZE <= 224
-#  define __SELECT_NUINT32 7
-#elif FD_SETSIZE <= 256
-#  define __SELECT_NUINT32 8
-#else
-#  warning "Larger fd_set needed"
-#endif
-
-/* These macros map a file descriptor to an index and bit number */
-
-#define _FD_NDX(fd)    ((fd) >> 5)
-#define _FD_BIT(fd)      ((fd) & 0x1f)
-
-/* Standard helper macros */
-
-#define FD_CLR(fd,set) \
-  ((((fd_set*)(set))->arr)[_FD_NDX(fd)] &= ~(1 << _FD_BIT(fd)))
-#define FD_SET(fd,set) \
-  ((((fd_set*)(set))->arr)[_FD_NDX(fd)] |= (1 << _FD_BIT(fd)))
-#define FD_ISSET(fd,set) \
-  (((((fd_set*)(set))->arr)[_FD_NDX(fd)] & (1 << _FD_BIT(fd))) != 0)
-#define FD_ZERO(set) \
-   memset((set), 0, sizeof(fd_set))
-
-typedef struct
-{
-    uint32_t arr[__SELECT_NUINT32];
-}fd_set;
+#ifdef __cplusplus
+extern "C" {
 #endif
 
 int select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout);
 
-#endif  /* end of RT_USING_LWIP */
+#ifdef __cplusplus
+}
+#endif
 
 #endif
+

include/libc/libc_fdset.h

+/*
+ * File      : libc_errno.h
+ * This file is part of RT-Thread RTOS
+ * COPYRIGHT (C) 2017, RT-Thread Development Team
+ *
+ *  This program is free software; you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation; either version 2 of the License, or
+ *  (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along
+ *  with this program; if not, write to the Free Software Foundation, Inc.,
+ *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2017-10-30     Bernard      The first version
+ */
+
+#ifndef LIBC_FDSET_H__
+#define LIBC_FDSET_H__
+
+#include <rtconfig.h>
+
+#ifdef RT_USING_NEWLIB
+#include <sys/types.h>
+#else
+
+#ifdef RT_USING_DFS_NET
+
+#ifdef FD_SETSIZE
+#undef FD_SETSIZE
+#endif
+
+#define FD_SETSIZE      DFS_FD_MAX
+#endif
+
+#  define	NBBY	8		/* number of bits in a byte */
+
+typedef	long	fd_mask;
+#  define	NFDBITS	(sizeof (fd_mask) * NBBY)	/* bits per mask */
+#  ifndef	howmany
+#	define	howmany(x,y)	(((x)+((y)-1))/(y))
+#  endif
+
+/* We use a macro for fd_set so that including Sockets.h afterwards
+   can work.  */
+typedef	struct _types_fd_set {
+	fd_mask	fds_bits[howmany(FD_SETSIZE, NFDBITS)];
+} _types_fd_set;
+
+#define fd_set _types_fd_set
+
+#  define	FD_SET(n, p)	((p)->fds_bits[(n)/NFDBITS] |= (1L << ((n) % NFDBITS)))
+#  define	FD_CLR(n, p)	((p)->fds_bits[(n)/NFDBITS] &= ~(1L << ((n) % NFDBITS)))
+#  define	FD_ISSET(n, p)	((p)->fds_bits[(n)/NFDBITS] & (1L << ((n) % NFDBITS)))
+#  define   FD_ZERO(p)      memset((void*)(p), 0, sizeof(*(p)))
+
+#endif
+
+#endif
+

include/libc/libc_stat.h

 #ifndef LIBC_STAT_H__
 #define LIBC_STAT_H__
 
+#include <rtconfig.h>
+
+#ifdef RT_USING_NEWLIB
+/* use header file of newlib */
+#include <sys/stat.h>
+#else
 #define S_IFMT               00170000
 #define S_IFSOCK             0140000
 #define S_IFLNK              0120000
@@ -36,5 +42,19 @@
 #define S_IWOTH              00002
 #define S_IXOTH              00001
 
+/* stat structure */
+#include <stdint.h>
+#include <time.h>
+
+struct stat
+{
+    struct rt_device* st_dev;
+    uint16_t st_mode;
+    uint32_t st_size;
+    time_t   st_mtime;
+    uint32_t st_blksize;
+};
+
 #endif
 
+#endif

include/rtlibc.h

@@ -33,6 +33,7 @@
 #include "libc/libc_ioctl.h"
 #include "libc/libc_dirent.h"
 #include "libc/libc_signal.h"
+#include "libc/libc_fdset.h"
 
 #if defined(__CC_ARM) || defined(__IAR_SYSTEMS_ICC__)
 typedef signed long off_t;