fs: allocate file/socket dynamically

Change-Id: I8aea63eaf0275f47f21fc8d5482b51ffecd5c906
Signed-off-by: Jiuzhu Dong <dongjiuzhu1@xiaomi.com>

include/aio.h

@@ -113,11 +113,7 @@ struct aiocb
   FAR volatile void *aio_buf;    /* Location of buffer */
   off_t aio_offset;              /* File offset */
   size_t aio_nbytes;             /* Length of transfer */
-#if CONFIG_NFILE_DESCRIPTORS > 127
   int16_t aio_fildes;            /* File descriptor (should be int) */
-#else
-  int8_t aio_fildes;             /* File descriptor (should be int) */
-#endif
   int8_t aio_reqprio;            /* Request priority offset (not used, should be int) */
   uint8_t aio_lio_opcode;        /* Operation to be performed (should be int) */
 

include/limits.h

@@ -120,10 +120,10 @@
 #define _POSIX_MAX_INPUT      255
 #define _POSIX_NAME_MAX       CONFIG_NAME_MAX
 #define _POSIX_NGROUPS_MAX    0
-#define _POSIX_OPEN_MAX       CONFIG_NFILE_DESCRIPTORS
+#define _POSIX_OPEN_MAX       INT_MAX
 #define _POSIX_PATH_MAX       CONFIG_PATH_MAX
 #define _POSIX_PIPE_BUF       512
-#define _POSIX_STREAM_MAX     CONFIG_NFILE_DESCRIPTORS
+#define _POSIX_STREAM_MAX     INT_MAX
 #define _POSIX_TZNAME_MAX     3
 
 #ifdef CONFIG_SMALL_MEMORY

include/nuttx/fs/fs.h

@@ -377,12 +377,18 @@ struct file
   FAR void         *f_priv;     /* Per file driver private data */
 };
 
-/* This defines a list of files indexed by the file descriptor */
+/* This defines a two layer array of files indexed by the file descriptor.
+ * Each row of this array is fixed size: CONFIG_NFILE_DESCRIPTORS_PER_BLOCK.
+ * You can get file instance in filelist by the follow methods:
+ * (file descriptor / CONFIG_NFILE_DESCRIPTORS_PER_BLOCK) as row index and
+ * (file descriptor % CONFIG_NFILE_DESCRIPTORS_PER_BLOCK) as column index.
+ */
 
 struct filelist
 {
-  sem_t   fl_sem;               /* Manage access to the file list */
-  struct file fl_files[CONFIG_NFILE_DESCRIPTORS];
+  sem_t             fl_sem;     /* Manage access to the file list */
+  uint8_t           fl_rows;    /* The number of rows of fl_files array */
+  FAR struct file **fl_files;   /* The pointer of two layer file descriptors array */
 };
 
 /* The following structure defines the list of files used for standard C I/O.
@@ -713,6 +719,20 @@ void files_initlist(FAR struct filelist *list);
 
 void files_releaselist(FAR struct filelist *list);
 
+/****************************************************************************
+ * Name: files_duplist
+ *
+ * Description:
+ *   Duplicate parent task's file descriptors.
+ *
+ * Returned Value:
+ *   Zero (OK) is returned on success; a negated errno value is returned on
+ *   any failure.
+ *
+ ****************************************************************************/
+
+int files_duplist(FAR struct filelist *plist, FAR struct filelist *clist);
+
 /****************************************************************************
  * Name: file_dup
  *

include/nuttx/net/net.h

@@ -77,13 +77,6 @@
 #  define _NX_RECVFROM(s,b,l,f,a,n) recvfrom(s,b,l,f,a,n)
 #endif
 
-/* Socket descriptors are the index into the TCB sockets list, offset by the
- * following amount. This offset is used to distinguish file descriptors from
- * socket descriptors
- */
-
-#define __SOCKFD_OFFSET CONFIG_NFILE_DESCRIPTORS
-
 /* Capabilities of a socket */
 
 #define SOCKCAP_NONBLOCKING (1 << 0)  /* Bit 0: Socket supports non-blocking

include/sys/select.h

@@ -37,7 +37,7 @@
 
 /* Get the total number of descriptors that we will have to support */
 
-#define FD_SETSIZE CONFIG_NFILE_DESCRIPTORS
+#define FD_SETSIZE 256
 
 /* 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?