Merged Eric Norum's select patch that was based on 4.0 and resolved

all conflicts.

15 files changed, 166 insertions, 121 deletions

diff --git a/c/src/exec/libcsupport/include/rtems/libio.h b/c/src/exec/libcsupport/include/rtems/libio.h
index ee0aaf9b7f..740574f303 100644
--- a/c/src/exec/libcsupport/include/rtems/libio.h
+++ b/c/src/exec/libcsupport/include/rtems/libio.h
@@ -393,12 +393,16 @@ typedef struct {
 #define LIBIO_FLAGS_NO_DELAY      0x0001  /* return immediately if no data */
 #define LIBIO_FLAGS_READ          0x0002  /* reading */
 #define LIBIO_FLAGS_WRITE         0x0004  /* writing */
-#define LIBIO_FLAGS_LINE_BUFFERED 0x0008  /* line buffered io (^h, ^u, etc) */
 #define LIBIO_FLAGS_OPEN          0x0100  /* device is open */
 #define LIBIO_FLAGS_APPEND        0x0200  /* all writes append */
 #define LIBIO_FLAGS_CREATE        0x0400  /* create file */
 #define LIBIO_FLAGS_CLOSE_ON_EXEC 0x0800  /* close on process exec() */
 
+#define LIBIO_FLAGS_HANDLER_SHIFT 12
+#define LIBIO_FLAGS_HANDLER_MASK  0xF000  /* mask for external handler type */
+#define LIBIO_FLAGS_HANDLER_RTEMS 0x0000  /* `traditional' RTEMS I/O */
+#define LIBIO_FLAGS_HANDLER_SOCK  0x1000  /* BSD socket */
+
 #define LIBIO_FLAGS_READ_WRITE    (LIBIO_FLAGS_READ | LIBIO_FLAGS_WRITE)
 
 
diff --git a/c/src/exec/libcsupport/include/rtems/libio_.h b/c/src/exec/libcsupport/include/rtems/libio_.h
index 33a9e7bda5..d595500430 100644
--- a/c/src/exec/libcsupport/include/rtems/libio_.h
+++ b/c/src/exec/libcsupport/include/rtems/libio_.h
@@ -65,6 +65,7 @@ extern rtems_id        rtems_libio_semaphore;
 extern unsigned32      rtems_libio_number_iops;
 extern rtems_libio_t  *rtems_libio_iops;
 extern rtems_libio_t  *rtems_libio_last_iop;
+extern rtems_libio_t *rtems_libio_iop_freelist;
 
 /*
  *  External I/O Handlers Table
diff --git a/c/src/exec/libcsupport/include/sys/sockio.h b/c/src/exec/libcsupport/include/sys/sockio.h
index 03ec16e43a..5e54baffe8 100644
--- a/c/src/exec/libcsupport/include/sys/sockio.h
+++ b/c/src/exec/libcsupport/include/sys/sockio.h
@@ -83,11 +83,10 @@
 #define	SIOCSIFMEDIA	_IOWR('i', 55, struct ifreq)	/* set net media */
 #define	SIOCGIFMEDIA	_IOWR('i', 56, struct ifmediareq) /* get net media */
 
-
 /*
  * RTEMS additions for setting/getting `tap' function on incoming packets.
  */
-#define SIOCSIFTAP	 _IOW('i', 80, struct ifreq)	/* set tap function */
-#define SIOCGIFTAP	_IOWR('i', 81, struct ifreq)	/* get tap function */
+#define SIOCSIFTAP	_IOW('i', 80, struct ifreq)	/* set tap function */
+#define SIOCGIFTAP	_IOW('i', 81, struct ifreq)	/* get tap function */
 
 #endif /* !_SYS_SOCKIO_H_ */
diff --git a/c/src/exec/libcsupport/src/close.c b/c/src/exec/libcsupport/src/close.c
index 94ddb45c90..0583a36b22 100644
--- a/c/src/exec/libcsupport/src/close.c
+++ b/c/src/exec/libcsupport/src/close.c
@@ -22,17 +22,18 @@ int close(
   rtems_status_code   rc;
   int                 status;
 
-  if ( rtems_file_descriptor_type( fd ) ) {
+  rtems_libio_check_fd(fd);
+  iop = rtems_libio_iop(fd);
+  if ( iop->flags & LIBIO_FLAGS_HANDLER_MASK ) {
     int (*fp)(int  fd);
 
-    fp = rtems_libio_handlers[rtems_file_descriptor_type_index(fd)].close;
+    fp = rtems_libio_handlers[
+            (iop->flags >> LIBIO_FLAGS_HANDLER_SHIFT) - 1].close;
     if ( fp == NULL )
       set_errno_and_return_minus_one( EBADF );
     status = (*fp)( fd );
     return status;
   }
-  iop = rtems_libio_iop(fd);
-  rtems_libio_check_fd(fd);
 
   if ( !iop->handlers )
     set_errno_and_return_minus_one( EBADF );
diff --git a/c/src/exec/libcsupport/src/fchmod.c b/c/src/exec/libcsupport/src/fchmod.c
index a3ca4507ab..f202a30eb0 100644
--- a/c/src/exec/libcsupport/src/fchmod.c
+++ b/c/src/exec/libcsupport/src/fchmod.c
@@ -27,19 +27,20 @@ int fchmod(
 {
   rtems_libio_t *iop;
   
+  rtems_libio_check_fd( fd );
+  iop = rtems_libio_iop( fd );
+
   /*
    *  If this is not a file system based entity, it is an error.
    */
 
-  if ( rtems_file_descriptor_type( fd ) )
+  if ( iop->flags & LIBIO_FLAGS_HANDLER_MASK )
     set_errno_and_return_minus_one( EBADF );
 
   /*
    *  Now process the fchmod().
    */
 
-  iop = rtems_libio_iop( fd );
-  rtems_libio_check_fd( fd );
   rtems_libio_check_permissions( iop, LIBIO_FLAGS_WRITE );
 
   if ( !iop->handlers->fchmod )
diff --git a/c/src/exec/libcsupport/src/fcntl.c b/c/src/exec/libcsupport/src/fcntl.c
index a538ec1cf9..b327a447ac 100644
--- a/c/src/exec/libcsupport/src/fcntl.c
+++ b/c/src/exec/libcsupport/src/fcntl.c
@@ -32,20 +32,20 @@ int fcntl(
   
   va_start( ap, cmd );
 
+  rtems_libio_check_fd( fd );
+  iop = rtems_libio_iop( fd );
+
   /*
    *  If this is not a file system based entity, it is an error.
    */
 
-  if ( rtems_file_descriptor_type( fd ) )
+  if ( iop->flags & LIBIO_FLAGS_HANDLER_MASK )
     set_errno_and_return_minus_one( EBADF );
 
   /*
    *  Now process the fcntl().
    */
 
-  iop = rtems_libio_iop( fd );
-  rtems_libio_check_fd( fd );
-
   /*
    *  This switch should contain all the cases from POSIX.
    */
diff --git a/c/src/exec/libcsupport/src/fdatasync.c b/c/src/exec/libcsupport/src/fdatasync.c
index 58a4c4e118..91bff3aaba 100644
--- a/c/src/exec/libcsupport/src/fdatasync.c
+++ b/c/src/exec/libcsupport/src/fdatasync.c
@@ -22,22 +22,22 @@ int fdatasync(
 {
   rtems_libio_t *iop;
 
+  rtems_libio_check_fd( fd );
+  iop = rtems_libio_iop( fd );
+  rtems_libio_check_permissions( iop, LIBIO_FLAGS_WRITE );
+
   /*
    *  If this file descriptor is mapped to an external set of handlers,
    *  then pass the request on to them.
    */
 
-  if ( rtems_file_descriptor_type( fd ) )
+  if ( iop->flags & LIBIO_FLAGS_HANDLER_MASK )
     set_errno_and_return_minus_one( EBADF );
 
   /*
    *  Now process the fdatasync().
    */
 
-  iop = rtems_libio_iop( fd );
-  rtems_libio_check_fd( fd );
-  rtems_libio_check_permissions( iop, LIBIO_FLAGS_WRITE );
-
   if ( !iop->handlers->fdatasync )
     set_errno_and_return_minus_one( ENOTSUP );
 
diff --git a/c/src/exec/libcsupport/src/fpathconf.c b/c/src/exec/libcsupport/src/fpathconf.c
index ea2377e15b..f3fb1162d0 100644
--- a/c/src/exec/libcsupport/src/fpathconf.c
+++ b/c/src/exec/libcsupport/src/fpathconf.c
@@ -26,23 +26,23 @@ long fpathconf(
   rtems_libio_t                          *iop;
   rtems_filesystem_limits_and_options_t  *the_limits;
 
+  rtems_libio_check_fd(fd);
+  iop = rtems_libio_iop(fd);
+  rtems_libio_check_permissions(iop, LIBIO_FLAGS_READ);
+
   /*
    *  If this file descriptor is mapped to an external set of handlers,
    *  then it is an error since fpathconf() is not included in the 
    *  set.
    */
 
-  if ( rtems_file_descriptor_type( fd ) )
+  if ( iop->flags & LIBIO_FLAGS_HANDLER_MASK )
     set_errno_and_return_minus_one( EBADF );
 
   /*
    *  Now process the information request.
    */
 
-  iop = rtems_libio_iop(fd);
-  rtems_libio_check_fd(fd);
-  rtems_libio_check_permissions(iop, LIBIO_FLAGS_READ);
-
   the_limits = &iop->pathinfo.mt_entry->pathconf_limits_and_options;
 
   switch ( name ) {
diff --git a/c/src/exec/libcsupport/src/fsync.c b/c/src/exec/libcsupport/src/fsync.c
index a5ed1e99e7..b77c77312c 100644
--- a/c/src/exec/libcsupport/src/fsync.c
+++ b/c/src/exec/libcsupport/src/fsync.c
@@ -22,22 +22,22 @@ int fsync(
 {
   rtems_libio_t *iop;
 
+  rtems_libio_check_fd( fd );
+  iop = rtems_libio_iop( fd );
+  rtems_libio_check_permissions( iop, LIBIO_FLAGS_WRITE );
+
   /*
    *  If this file descriptor is mapped to an external set of handlers,
    *  then pass the request on to them.
    */
 
-  if ( rtems_file_descriptor_type( fd ) )
+  if ( iop->flags & LIBIO_FLAGS_HANDLER_MASK )
     set_errno_and_return_minus_one( EBADF );
 
   /*
    *  Now process the fsync().
    */
 
-  iop = rtems_libio_iop( fd );
-  rtems_libio_check_fd( fd );
-  rtems_libio_check_permissions( iop, LIBIO_FLAGS_WRITE );
-
   if ( !iop->handlers->fsync )
     set_errno_and_return_minus_one( ENOTSUP );
 
diff --git a/c/src/exec/libcsupport/src/ftruncate.c b/c/src/exec/libcsupport/src/ftruncate.c
index 7fb2286531..5bcb2ea5d8 100644
--- a/c/src/exec/libcsupport/src/ftruncate.c
+++ b/c/src/exec/libcsupport/src/ftruncate.c
@@ -25,19 +25,20 @@ int ftruncate(
   rtems_libio_t                    *iop;
   rtems_filesystem_location_info_t  loc;
   
+  rtems_libio_check_fd( fd );
+  iop = rtems_libio_iop( fd );
+
   /*
    *  If this is not a file system based entity, it is an error.
    */
 
-  if ( rtems_file_descriptor_type( fd ) )
+  if ( iop->flags & LIBIO_FLAGS_HANDLER_MASK )
     set_errno_and_return_minus_one( EBADF );
 
   /*
    *  Now process the ftruncate() request.
    */
   
-  iop = rtems_libio_iop( fd );
-
   /*
    *  Make sure we are not working on a directory
    */
@@ -49,7 +50,6 @@ int ftruncate(
   if ( (*loc.ops->node_type)( &loc ) == RTEMS_FILESYSTEM_DIRECTORY )
     set_errno_and_return_minus_one( EISDIR );
 
-  rtems_libio_check_fd( fd );
   rtems_libio_check_permissions( iop, LIBIO_FLAGS_WRITE );
 
   if ( !iop->handlers->ftruncate )
diff --git a/c/src/exec/libcsupport/src/ioctl.c b/c/src/exec/libcsupport/src/ioctl.c
index 0aaf0379ae..9284c7f9dc 100644
--- a/c/src/exec/libcsupport/src/ioctl.c
+++ b/c/src/exec/libcsupport/src/ioctl.c
@@ -26,15 +26,19 @@ int ioctl(
   rtems_status_code  rc;
   rtems_libio_t     *iop;
 
+  rtems_libio_check_fd( fd );
+  iop = rtems_libio_iop( fd );
+
   /*
    *  If this file descriptor is mapped to an external set of handlers,
    *  then pass the request on to them.
    */ 
 
-  if ( rtems_file_descriptor_type( fd ) ) {
+  if ( iop->flags & LIBIO_FLAGS_HANDLER_MASK ) {
     rtems_libio_ioctl_t fp;
 
-    fp = rtems_libio_handlers[rtems_file_descriptor_type_index(fd)].ioctl;
+    fp = rtems_libio_handlers[
+           (iop->flags >> LIBIO_FLAGS_HANDLER_SHIFT) - 1].ioctl;
     if ( fp == NULL )
       set_errno_and_return_minus_one( EBADF );
 
@@ -45,9 +49,6 @@ int ioctl(
    *  Now process the ioctl().
    */
 
-  iop = rtems_libio_iop( fd );
-  rtems_libio_check_fd( fd );
-
   if ( !iop->handlers->ioctl )
     set_errno_and_return_minus_one( ENOTSUP );
 
diff --git a/c/src/exec/libcsupport/src/libio.c b/c/src/exec/libcsupport/src/libio.c
index e63a4626d4..88aea9b62f 100644
--- a/c/src/exec/libcsupport/src/libio.c
+++ b/c/src/exec/libcsupport/src/libio.c
@@ -3,9 +3,6 @@
  *  table of integer style file descriptors used by the low level
  *  POSIX system calls like open(), read, fstat(), etc.
  *
- *  This provides the foundation for POSIX compliant IO system calls
- *  for RTEMS.
- *
  *  COPYRIGHT (c) 1989-1998.
  *  On-Line Applications Research Corporation (OAR).
  *  Copyright assigned to U.S. Government, 1994.
@@ -18,18 +15,56 @@
  */
 
 #include "libio_.h"                   /* libio_.h pulls in rtems */
+#include <rtems.h>
+#include <rtems/assoc.h>                /* assoc.h not included by rtems.h */
+
+#include <stdio.h>                      /* O_RDONLY, et.al. */
+#include <fcntl.h>                      /* O_RDONLY, et.al. */
+#include <assert.h>
+#include <errno.h>
+
+#if ! defined(O_NDELAY)
+# if defined(solaris2)
+#  define O_NDELAY O_NONBLOCK
+# elif defined(RTEMS_NEWLIB)
+#  define O_NDELAY _FNBIO
+# endif
+#endif
+
+
+#include <errno.h>
+#include <string.h>                     /* strcmp */
+#include <unistd.h>
+#include <stdlib.h>                     /* calloc() */
+
+#include "libio.h"                      /* libio.h not pulled in by rtems */
+
+/*                            
+ *  File descriptor Table Information
+ */         
+
+extern unsigned32  rtems_libio_number_iops;
+rtems_id           rtems_libio_semaphore;
+rtems_libio_t     *rtems_libio_iops;
+rtems_libio_t     *rtems_libio_last_iop;
+rtems_libio_t     *rtems_libio_iop_freelist;
 
 /*
- *  Global variables used to manage the File Descriptor Table.
- *  IOP = IO Pointer.
+ *  External I/O Handlers Table
+ *
+ *  Space for all possible handlers is preallocated
+ *  to speed up dispatch to external handlers.
  */
 
-rtems_id                rtems_libio_semaphore;
-rtems_libio_t          *rtems_libio_iops;
-rtems_libio_t          *rtems_libio_last_iop;
 rtems_libio_handler_t   rtems_libio_handlers[15];
 
 /*
+ *  Default mode for all files.
+ */
+
+mode_t    rtems_filesystem_umask;
+
+/*
  *  rtems_register_libio_handler
  *
  *  This function registers an external IO handler set.  This lets
@@ -44,8 +79,7 @@ void rtems_register_libio_handler(
   const rtems_libio_handler_t *handler
 )
 {
-  int handler_index = rtems_file_descriptor_type_index( handler_flag );
-
+  int handler_index = (handler_flag >> LIBIO_FLAGS_HANDLER_SHIFT) - 1;
 
   if ((handler_index < 0) || (handler_index >= 15))
     rtems_fatal_error_occurred( RTEMS_INVALID_NUMBER );
@@ -61,21 +95,22 @@ void rtems_register_libio_handler(
 
 void rtems_libio_init( void )
 {
-  rtems_status_code rc;
-
-  /*
-   *  Allocate memory for the IOP Table
-   */
-
-  if ( rtems_libio_number_iops > 0 ) {
-    rtems_libio_iops =
-      (rtems_libio_t *) calloc(rtems_libio_number_iops, sizeof(rtems_libio_t));
-
-    if (rtems_libio_iops == NULL)
-        rtems_fatal_error_occurred( RTEMS_NO_MEMORY );
-
-    rtems_libio_last_iop = rtems_libio_iops + (rtems_libio_number_iops - 1);
-  }
+    rtems_status_code rc;
+    int i;
+    rtems_libio_t *iop;
+
+    if (rtems_libio_number_iops > 0)
+    {
+        rtems_libio_iops = (rtems_libio_t *) calloc(rtems_libio_number_iops,
+                                                    sizeof(rtems_libio_t));
+        if (rtems_libio_iops == NULL)
+            rtems_fatal_error_occurred(RTEMS_NO_MEMORY);
+
+        iop = rtems_libio_iop_freelist = rtems_libio_iops;
+	for (i = 0 ; i < (rtems_libio_number_iops - 1) ; i++, iop++)
+		iop->data1 = iop + 1;
+	iop->data1 = NULL;
+    }
 
   /*
    *  Create the binary semaphore used to provide mutual exclusion
@@ -157,24 +192,21 @@ rtems_libio_t *rtems_libio_allocate( void )
   
   rtems_semaphore_obtain( rtems_libio_semaphore, RTEMS_WAIT, RTEMS_NO_TIMEOUT );
 
-  for (iop = rtems_libio_iops; iop <= rtems_libio_last_iop; iop++)
-    if ((iop->flags & LIBIO_FLAGS_OPEN) == 0) {
-      /*
-       *  Got an IOP -- create a semaphore for it.
-       */
-
-      rc = rtems_semaphore_create(
-        RTEMS_LIBIO_IOP_SEM(iop - rtems_libio_iops),
-        1,
-        RTEMS_BINARY_SEMAPHORE | RTEMS_INHERIT_PRIORITY | RTEMS_PRIORITY,
-        RTEMS_NO_PRIORITY,
-        &iop->sem
-      );
-      if ( rc != RTEMS_SUCCESSFUL )
-        goto failed;
-    
-      iop->flags = LIBIO_FLAGS_OPEN;
-      goto done;
+  if (rtems_libio_iop_freelist) {
+    iop = rtems_libio_iop_freelist;
+    rc = rtems_semaphore_create(
+      RTEMS_LIBIO_IOP_SEM(iop - rtems_libio_iops),
+      1,
+      RTEMS_BINARY_SEMAPHORE | RTEMS_INHERIT_PRIORITY | RTEMS_PRIORITY,
+      RTEMS_NO_PRIORITY,
+      &iop->sem
+    );
+    if (rc != RTEMS_SUCCESSFUL)
+      goto failed;
+    rtems_libio_iop_freelist = iop->data1;
+    iop->data1 = 0;
+    iop->flags = LIBIO_FLAGS_OPEN;
+    goto done;
   }
   
 failed:
@@ -198,19 +230,20 @@ void rtems_libio_free(
 {
   rtems_semaphore_obtain( rtems_libio_semaphore, RTEMS_WAIT, RTEMS_NO_TIMEOUT );
 
-  if (iop->sem)
-    rtems_semaphore_delete(iop->sem);
+    if (iop->sem)
+      rtems_semaphore_delete(iop->sem);
 
-  (void) memset(iop, 0, sizeof(*iop));
+    iop->data1 = rtems_libio_iop_freelist;
+    rtems_libio_iop_freelist = iop;
 
-  rtems_semaphore_release( rtems_libio_semaphore );
+  rtems_semaphore_release(rtems_libio_semaphore);
 }
 
 /*
  *  rtems_libio_is_open_files_in_fs
  *
  *  This routine scans the entire file descriptor table to determine if the
- *  are any active file descriptors that refer to the atleast one node in the
+ *  are any active file descriptors that refer to the at least one node in the
  *  file system that we are trying to dismount.
  *
  *  If there is at least one node in the file system referenced by the mount 
@@ -225,19 +258,19 @@ int rtems_libio_is_open_files_in_fs(
   int                result = 0;
 
   rtems_semaphore_obtain( rtems_libio_semaphore, RTEMS_WAIT, RTEMS_NO_TIMEOUT );
-
+              
   /*
    *  Look for any active file descriptor entry.
-   */
-
+   */         
+     
   for ( iop=rtems_libio_iops ; iop <= rtems_libio_last_iop ; iop++ ) {
-
+        
     if ((iop->flags & LIBIO_FLAGS_OPEN) != 0) {
-
+        
        /*
         *  Check if this node is under the file system that we
         *  are trying to dismount.
-        */ 
+        */
 
        if ( iop->pathinfo.mt_entry == fs_mt_entry ) {
           result = 1;
@@ -247,7 +280,7 @@ int rtems_libio_is_open_files_in_fs(
   }
 
   rtems_semaphore_release( rtems_libio_semaphore );
-
+ 
   return result;
 }
 
@@ -256,7 +289,7 @@ int rtems_libio_is_open_files_in_fs(
  *
  *  This routine scans the entire file descriptor table to determine if the
  *  given file refers to an active file descriptor.
- *
+ * 
  *  If the given file is open a 1 is returned, otherwise a 0 is returned.
  */
 
@@ -265,22 +298,22 @@ int rtems_libio_is_file_open(
 )
 {
   rtems_libio_t     *iop;
-  int                result=0; 
+  int                result=0;
 
   rtems_semaphore_obtain( rtems_libio_semaphore, RTEMS_WAIT, RTEMS_NO_TIMEOUT );
 
   /*
    *  Look for any active file descriptor entry.
    */
-
+  
   for ( iop=rtems_libio_iops ; iop <= rtems_libio_last_iop ; iop++ ) {
-
+  
     if ((iop->flags & LIBIO_FLAGS_OPEN) != 0) {
-
+  
        /*
         *  Check if this node is under the file system that we
         *  are trying to dismount.
-        */ 
+        */
 
        if ( iop->pathinfo.node_access == node_access ) {
           result = 1;
@@ -293,3 +326,5 @@ int rtems_libio_is_file_open(
 
   return result;
 }
+
+
diff --git a/c/src/exec/libcsupport/src/lseek.c b/c/src/exec/libcsupport/src/lseek.c
index 514f8cd912..cd8046356f 100644
--- a/c/src/exec/libcsupport/src/lseek.c
+++ b/c/src/exec/libcsupport/src/lseek.c
@@ -24,15 +24,19 @@ off_t lseek(
 {
   rtems_libio_t *iop;
 
+  rtems_libio_check_fd( fd );
+  iop = rtems_libio_iop( fd );
+
   /*
    *  If this file descriptor is mapped to an external set of handlers,
    *  then pass the request on to them.
    */
 
-  if ( rtems_file_descriptor_type( fd ) ) {
+  if ( iop->flags & LIBIO_FLAGS_HANDLER_MASK ) {
     rtems_libio_lseek_t fp;
 
-    fp = rtems_libio_handlers[rtems_file_descriptor_type_index(fd)].lseek;
+    fp = rtems_libio_handlers[
+           (iop->flags >> LIBIO_FLAGS_HANDLER_SHIFT) - 1].lseek;
     if ( fp == NULL )
       set_errno_and_return_minus_one( EBADF );
 
@@ -43,9 +47,6 @@ off_t lseek(
    *  Now process the lseek().
    */
 
-  iop = rtems_libio_iop( fd );
-  rtems_libio_check_fd( fd );
-
   switch ( whence ) {
     case SEEK_SET:
       iop->offset = offset;
diff --git a/c/src/exec/libcsupport/src/read.c b/c/src/exec/libcsupport/src/read.c
index 150fe675ab..1ed6a0bd00 100644
--- a/c/src/exec/libcsupport/src/read.c
+++ b/c/src/exec/libcsupport/src/read.c
@@ -26,15 +26,22 @@ int read(
   int             rc;  /* XXX change to a size_t when prototype is fixed */
   rtems_libio_t *iop;
 
+  rtems_libio_check_fd( fd );
+  iop = rtems_libio_iop( fd );
+  rtems_libio_check_buffer( buffer );
+  rtems_libio_check_count( count );
+  rtems_libio_check_permissions( iop, LIBIO_FLAGS_READ );
+
   /*
    *  If this file descriptor is mapped to an external set of handlers,
    *  then pass the request on to them.
    */ 
 
-  if ( rtems_file_descriptor_type( fd ) ) {
+  if ( iop->flags & LIBIO_FLAGS_HANDLER_MASK ) {
     rtems_libio_read_t fp;
 
-    fp = rtems_libio_handlers[rtems_file_descriptor_type_index(fd)].read;
+    fp = rtems_libio_handlers[
+           (iop->flags >> LIBIO_FLAGS_HANDLER_SHIFT) - 1].read;
     if ( fp == NULL )
       set_errno_and_return_minus_one( EBADF );
 
@@ -45,12 +52,6 @@ int read(
    *  Now process the read().
    */
 
-  iop = rtems_libio_iop( fd );
-  rtems_libio_check_fd( fd );
-  rtems_libio_check_buffer( buffer );
-  rtems_libio_check_count( count );
-  rtems_libio_check_permissions( iop, LIBIO_FLAGS_READ );
-
   if ( !iop->handlers->read )
     set_errno_and_return_minus_one( ENOTSUP );
 
diff --git a/c/src/exec/libcsupport/src/write.c b/c/src/exec/libcsupport/src/write.c
index 7e0953bb90..3de21f0d0f 100644
--- a/c/src/exec/libcsupport/src/write.c
+++ b/c/src/exec/libcsupport/src/write.c
@@ -34,15 +34,22 @@ int write(                        /* XXX this should return a ssize_t */
   rtems_status_code  rc;
   rtems_libio_t     *iop;
 
+  rtems_libio_check_fd( fd );
+  iop = rtems_libio_iop( fd );
+  rtems_libio_check_buffer( buffer );
+  rtems_libio_check_count( count );
+  rtems_libio_check_permissions( iop, LIBIO_FLAGS_WRITE );
+
   /*
    *  If this file descriptor is mapped to an external set of handlers,
    *  then pass the request on to them.
    */
 
-  if ( rtems_file_descriptor_type( fd ) ) {
+  if ( iop->flags & LIBIO_FLAGS_HANDLER_MASK ) {
     rtems_libio_write_t fp;
 
-    fp = rtems_libio_handlers[rtems_file_descriptor_type_index(fd)].write;
+    fp = rtems_libio_handlers[
+           (iop->flags >> LIBIO_FLAGS_HANDLER_SHIFT) - 1].write;
     if ( fp == NULL )
       set_errno_and_return_minus_one( EBADF );
 
@@ -53,12 +60,6 @@ int write(                        /* XXX this should return a ssize_t */
    *  Now process the write() request.
    */
 
-  iop = rtems_libio_iop( fd );
-  rtems_libio_check_fd( fd );
-  rtems_libio_check_buffer( buffer );
-  rtems_libio_check_count( count );
-  rtems_libio_check_permissions( iop, LIBIO_FLAGS_WRITE );
-
   if ( !iop->handlers->write )
     set_errno_and_return_minus_one( ENOTSUP );