fflush(NULL) returns error

git-svn-id: svn://svn.code.sf.net/p/nuttx/code/trunk@636 42af7a65-404d-4744-a932-0658087f49c3

7 files changed, 373 insertions, 179 deletions

diff --git a/nuttx/lib/Makefile b/nuttx/lib/Makefile
index 6e852d9d0..840ea0779 100644
--- a/nuttx/lib/Makefile
+++ b/nuttx/lib/Makefile
@@ -61,9 +61,9 @@ STDIO_SRCS	+= lib_rawstream.c
 ifneq ($(CONFIG_NFILE_STREAMS),0)
 STDIO_SRCS	+= lib_fopen.c lib_fclose.c lib_fread.c lib_libfread.c lib_fseek.c \
 		   lib_fgetc.c lib_fgets.c lib_gets.c lib_fwrite.c lib_libfwrite.c \
-		   lib_fflush.c lib_rdflush.c lib_wrflush.c lib_fputc.c lib_puts.c \
-		   lib_fputs.c lib_ungetc.c lib_vprintf.c lib_fprintf.c lib_vfprintf.c \
-		   lib_stdstream.c
+		   lib_fflush.c lib_libflushall.c lib_libfflush.c lib_rdflush.c lib_wrflush.c \
+		   lib_fputc.c lib_puts.c lib_fputs.c lib_ungetc.c lib_vprintf.c \
+		   lib_fprintf.c lib_vfprintf.c lib_stdstream.c
 endif
 endif
 
diff --git a/nuttx/lib/lib_fflush.c b/nuttx/lib/lib_fflush.c
index 929597ea8..d73217437 100644
--- a/nuttx/lib/lib_fflush.c
+++ b/nuttx/lib/lib_fflush.c
@@ -41,11 +41,10 @@
  * Included Files
  ****************************************************************************/
 
-#include <nuttx/config.h>  /* for CONFIG_STDIO_BUFFER_SIZE */
+#include <nuttx/config.h>
 
 #include <sys/types.h>
 #include <stdio.h>
-#include <unistd.h>
 #include <fcntl.h>
 #include <errno.h>
 
@@ -82,167 +81,10 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Name: fflush_internal
- *
- * Description:
- *  The function fflush() forces a write of all user-space buffered data for
- *  the given output or update stream via the stream's underlying write
- *  function.  The open status of the stream is unaffected.
- *
- * Parmeters:
- *  stream - the stream to flush
- *  bforce - flush must be complete.
- *
- * Return:
- *  ERROR on failure, otherwise the number of bytes remaining in the buffer.
- *  If bforce is set, then only the values ERROR and 0 will be returned.
- *
- ****************************************************************************/
-
-ssize_t fflush_internal(FILE *stream, boolean bforce)
-{
-#if CONFIG_STDIO_BUFFER_SIZE > 0
-  const unsigned char *src;
-  size_t bytes_written;
-  size_t nbuffer;
-
-  /* Return EBADF if the file is not opened for writing */
-
-  if (stream->fs_filedes < 0 || (stream->fs_oflags & O_WROK) == 0)
-    {
-      *get_errno_ptr() = EBADF;
-      return ERROR;
-    }
-
-  /* Make sure that we have exclusive access to the stream */
-
-  lib_take_semaphore(stream);
-
-  /* Make sure tht the buffer holds valid data */
-
-  if (stream->fs_bufpos  != stream->fs_bufstart)
-    {
-       /* Make sure that the buffer holds buffered write data.  We do not
-        * support concurrent read/write buffer usage.
-        */
-
-       if (stream->fs_bufread != stream->fs_bufstart)
-        {
-          /* The buffer holds read data... just return zero */
-
-          return 0;
-        }
-
-      /* How many bytes of write data are used in the buffer now */
-
-      nbuffer = stream->fs_bufpos - stream->fs_bufstart;
-
-      /* Try to write that amount */
-
-      src = stream->fs_bufstart;
-      do
-        {
-          /* Perform the write */
-
-          bytes_written = write(stream->fs_filedes, src, nbuffer);
-          if (bytes_written < 0)
-            {
-              lib_give_semaphore(stream);
-              return ERROR;
-            }
-
-          /* Handle partial writes.  fflush() must either return with
-           * an error condition or with the data successfully flushed
-           * from the buffer.
-           */
-
-          src     += bytes_written;
-          nbuffer -= bytes_written;
-        }
-      while (bforce && nbuffer > 0);
-
-      /* Reset the buffer position to the beginning of the buffer */
-
-      stream->fs_bufpos = stream->fs_bufstart;
-
-      /* For the case of an incomplete write, nbuffer will be non-zero
-       * It will hold the number of bytes that were not written.
-       * Move the data down in the buffer to handle this (rare) case
-       */
-
-      while (nbuffer)
-       {
-         *stream->fs_bufpos++ = *src++;
-         --nbuffer;
-       }
-    }
-
-  /* Restore normal access to the stream and return the number of bytes
-   * remaining in the buffer.
-   */
-
-  lib_give_semaphore(stream);
-  return stream->fs_bufpos - stream->fs_bufstart;
-#else
-  /* Return no bytes remaining in the buffer */
-
-  return 0;
-#endif
-}
-
-/****************************************************************************
  * Global Functions
  ****************************************************************************/
 
 /****************************************************************************
- * Name: lib_fflushall
- *
- * Description:
- *   Called either (1) by the OS when a task exits, or (2) from fflush()
- *   when a NULL stream argument is provided.
- *
- ****************************************************************************/
-
-int lib_flushall(FAR struct streamlist *list)
-{
-  int lasterrno = OK;
-  int ret;
-
-  /* Make sure that there are streams associated with this thread */
-
-  if (list)
-    {
-       int i;
-
-       /* Process each stream in the thread's stream list */
-
-       stream_semtake(list);
-       for (i = 0; i < CONFIG_NFILE_STREAMS; i++)
-         {
-           /* If the stream is open (i.e., assigned a non-negative file
-            * descriptor), then flush all of the pending write data in the
-            * stream.
-            */
-
-           if (list->sl_streams[i].fs_filedes >= 0)
-             {
-               if (fflush_internal(&list->sl_streams[i], TRUE) != 0)
-                 {
-                   lasterrno = *get_errno_ptr();
-                   ret = ERROR;
-                 }
-             }
-         }
-       stream_semgive(list);
-    }
-
-  /* If any flush failed, return that last failed flush */
-
-  *get_errno_ptr() = lasterrno;
-  return ret;
-}
-
-/****************************************************************************
  * Name: fflush
  *
  * Description:
@@ -259,12 +101,20 @@ int lib_flushall(FAR struct streamlist *list)
 
 int fflush(FILE *stream)
 {
+  /* Is the stream argument NULL? */
+
   if (!stream)
     {
+      /* Yes... then this is a request to flush all streams */
+
       return lib_flushall(sched_getstreams());
     }
-  else if (fflush_internal(stream, TRUE) != 0)
+  else if (lib_fflush(stream, TRUE) != 0)
     {
+      /* An error occurred during the flush AND/OR we were unable to flush all
+       * of the buffered write data.  Return EOF on failure.
+       */
+
       return EOF;
     }
   return OK;
diff --git a/nuttx/lib/lib_internal.h b/nuttx/lib/lib_internal.h
index 4e3a508a8..d45d0ba03 100644
--- a/nuttx/lib/lib_internal.h
+++ b/nuttx/lib/lib_internal.h
@@ -160,9 +160,9 @@ extern ssize_t lib_fwrite(const void *ptr, size_t count, FILE *stream);
 
 extern ssize_t lib_fread(void *ptr, size_t count, FILE *stream);
 
-/* Defined in lib_fflush.c */
+/* Defined in lib_libfflush.c */
 
-extern ssize_t fflush_internal(FILE *stream, boolean bforce);
+extern ssize_t lib_fflush(FILE *stream, boolean bforce);
 
 /* Defined in lib_rdflush.c */
 
diff --git a/nuttx/lib/lib_libfflush.c b/nuttx/lib/lib_libfflush.c
new file mode 100644
index 000000000..52af91c8d
--- /dev/null
+++ b/nuttx/lib/lib_libfflush.c
@@ -0,0 +1,195 @@
+/****************************************************************************
+ * lib/lib_libfflush.c
+ *
+ *   Copyright (C) 2007, 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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Compilation Switches
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#include <nuttx/fs.h>
+
+#include "lib_internal.h"
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: lib_fflush
+ *
+ * Description:
+ *  The function lib_fflush() forces a write of all user-space buffered data for
+ *  the given output or update stream via the stream's underlying write
+ *  function.  The open status of the stream is unaffected.
+ *
+ * Parmeters:
+ *  stream - the stream to flush
+ *  bforce - flush must be complete.
+ *
+ * Return:
+ *  ERROR on failure, otherwise the number of bytes remaining in the buffer.
+ *  If bforce is set, then only the values ERROR and 0 will be returned.
+ *
+ ****************************************************************************/
+
+ssize_t lib_fflush(FILE *stream, boolean bforce)
+{
+#if CONFIG_STDIO_BUFFER_SIZE > 0
+  const unsigned char *src;
+  size_t bytes_written;
+  size_t nbuffer;
+
+  /* Return EBADF if the file is not opened for writing */
+
+  if (stream->fs_filedes < 0 || (stream->fs_oflags & O_WROK) == 0)
+    {
+      *get_errno_ptr() = EBADF;
+      return ERROR;
+    }
+
+  /* Make sure that we have exclusive access to the stream */
+
+  lib_take_semaphore(stream);
+
+  /* Make sure tht the buffer holds valid data */
+
+  if (stream->fs_bufpos  != stream->fs_bufstart)
+    {
+       /* Make sure that the buffer holds buffered write data.  We do not
+        * support concurrent read/write buffer usage.
+        */
+
+       if (stream->fs_bufread != stream->fs_bufstart)
+        {
+          /* The buffer holds read data... just return zero */
+
+          return 0;
+        }
+
+      /* How many bytes of write data are used in the buffer now */
+
+      nbuffer = stream->fs_bufpos - stream->fs_bufstart;
+
+      /* Try to write that amount */
+
+      src = stream->fs_bufstart;
+      do
+        {
+          /* Perform the write */
+
+          bytes_written = write(stream->fs_filedes, src, nbuffer);
+          if (bytes_written < 0)
+            {
+              lib_give_semaphore(stream);
+              return ERROR;
+            }
+
+          /* Handle partial writes.  fflush() must either return with
+           * an error condition or with the data successfully flushed
+           * from the buffer.
+           */
+
+          src     += bytes_written;
+          nbuffer -= bytes_written;
+        }
+      while (bforce && nbuffer > 0);
+
+      /* Reset the buffer position to the beginning of the buffer */
+
+      stream->fs_bufpos = stream->fs_bufstart;
+
+      /* For the case of an incomplete write, nbuffer will be non-zero
+       * It will hold the number of bytes that were not written.
+       * Move the data down in the buffer to handle this (rare) case
+       */
+
+      while (nbuffer)
+       {
+         *stream->fs_bufpos++ = *src++;
+         --nbuffer;
+       }
+    }
+
+  /* Restore normal access to the stream and return the number of bytes
+   * remaining in the buffer.
+   */
+
+  lib_give_semaphore(stream);
+  return stream->fs_bufpos - stream->fs_bufstart;
+#else
+  /* Return no bytes remaining in the buffer */
+
+  return 0;
+#endif
+}
+
diff --git a/nuttx/lib/lib_libflushall.c b/nuttx/lib/lib_libflushall.c
new file mode 100644
index 000000000..7ba72dc7a
--- /dev/null
+++ b/nuttx/lib/lib_libflushall.c
@@ -0,0 +1,140 @@
+/****************************************************************************
+ * lib/lib_libflushall.c
+ *
+ *   Copyright (C) 2007, 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.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Compilation Switches
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <nuttx/config.h>
+
+#include <sys/types.h>
+#include <fcntl.h>
+#include <errno.h>
+
+#include <nuttx/fs.h>
+
+#include "lib_internal.h"
+
+/****************************************************************************
+ * Definitions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Type Declarations
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Constant Data
+ ****************************************************************************/
+
+/****************************************************************************
+ * Private Variables
+ ****************************************************************************/
+
+/****************************************************************************
+ * Global Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: lib_flushall
+ *
+ * Description:
+ *   Called either (1) by the OS when a task exits, or (2) from fflush()
+ *   when a NULL stream argument is provided.
+ *
+ ****************************************************************************/
+
+int lib_flushall(FAR struct streamlist *list)
+{
+  int lasterrno = OK;
+  int ret;
+
+  /* Make sure that there are streams associated with this thread */
+
+  if (list)
+    {
+       int i;
+
+       /* Process each stream in the thread's stream list */
+
+       stream_semtake(list);
+       for (i = 0; i < CONFIG_NFILE_STREAMS; i++)
+         {
+           FILE *stream = &list->sl_streams[i];
+
+           /* If the stream is open (i.e., assigned a non-negative file
+            * descriptor) and opened for writing, then flush all of the pending
+            * write data in the stream.
+            */
+
+           if (stream->fs_filedes >= 0 && (stream->fs_oflags & O_WROK) != 0)
+             {
+               /* Flush the writable FILE */
+
+               if (lib_fflush(stream, TRUE) != 0)
+                 {
+                   /* An error occurred during the flush AND/OR we were unable
+                    * to flush all of the buffered write data.  Return EOF on failure.
+                    */
+
+                   lasterrno = *get_errno_ptr();
+                   ret = ERROR;
+                 }
+             }
+         }
+       stream_semgive(list);
+    }
+
+  /* If any flush failed, return that last failed flush */
+
+  *get_errno_ptr() = lasterrno;
+  return ret;
+}
diff --git a/nuttx/lib/lib_libfwrite.c b/nuttx/lib/lib_libfwrite.c
index 01bc3c285..b7f681051 100644
--- a/nuttx/lib/lib_libfwrite.c
+++ b/nuttx/lib/lib_libfwrite.c
@@ -155,7 +155,7 @@ ssize_t lib_fwrite(const void *ptr, size_t count, FILE *stream)
         {
           /* Flush the buffered data to the IO stream */
 
-          int bytes_buffered = fflush_internal(stream, FALSE);
+          int bytes_buffered = lib_fflush(stream, FALSE);
           if (bytes_buffered < 0)
             {
               goto errout_with_semaphore;
diff --git a/nuttx/lib/lib_wrflush.c b/nuttx/lib/lib_wrflush.c
index cc2f65543..73e24afec 100644
--- a/nuttx/lib/lib_wrflush.c
+++ b/nuttx/lib/lib_wrflush.c
@@ -1,5 +1,5 @@
 /****************************************************************************
- * lib/lib_wrlush.c
+ * lib/lib_wrflush.c
  *
  *   Copyright (C) 2008 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
@@ -90,22 +90,31 @@
  *
  ****************************************************************************/
 
-/****************************************************************************
- * Name: lib_wrflush
- ****************************************************************************/
-
 int lib_wrflush(FILE *stream)
 {
-#if CONFIG_STDIO_BUFFER_SIZE > 0
-  /* Verify that the stream is opened for writing... flush will return an
-   * error if it is called for a stream that is not opened for writing.
-   */
+  /* Verify that we were passed a valid (i.e., non-NULL) stream */
 
-  if (stream && (stream->fs_oflags & O_WROK) != 0)
+#if CONFIG_STDIO_BUFFER_SIZE > 0
+  if (stream)
     {
-      return fflush(stream);
+      /* Verify that the stream is opened for writing... lib_fflush will
+       * return an error if it is called for a stream that is not opened for
+       * writing.
+       */
+
+      if ((stream->fs_oflags & O_WROK) == 0 ||
+          lib_fflush(stream, TRUE) == 0)
+       {
+         /* Return success if there is no buffered write data -- i.e., that
+          * the stream is not opened for writing or, if it is, that all of
+          * the buffered write data was successfully flushed.
+          */
+
+         return OK;
+       }
     }
+  return ERROR;
+#else
+  return stream ? OK : ERROR;
 #endif
-  return OK;
 }
-