Complete fragmentary support for ferror(). From Macs N

7 files changed, 28 insertions, 46 deletions

diff --git a/nuttx/ChangeLog b/nuttx/ChangeLog
index 6957d7b9a..9a439dcb5 100644
--- a/nuttx/ChangeLog
+++ b/nuttx/ChangeLog
@@ -7089,4 +7089,6 @@
 	  return EOF if no values were converted (2014-3-30).
 	* include/time.h and sched/clock_settime(): Add support for
 	  CLOCK_REALTIME.  From Macs N (2014-3-31).
-
+	* libc/stdio/lib_ferror.c, lib_fread.c, lib_libfflush.c,
+	  lib_libfread.c, and lib_libfwrite.c:  Finish incomplete support
+	  for ferror().  From Macs N (2014-3-14).
diff --git a/nuttx/TODO b/nuttx/TODO
index 0a1272e9f..275c7e759 100644
--- a/nuttx/TODO
+++ b/nuttx/TODO
@@ -17,7 +17,7 @@ nuttx/
   (6)  Binary loaders (binfmt/)
  (17)  Network (net/, drivers/net)
   (4)  USB (drivers/usbdev, drivers/usbhost)
- (11)  Libraries (libc/, )
+ (10)  Libraries (libc/, )
  (12)  File system/Generic drivers (fs/, drivers/)
   (5)  Graphics subystem (graphics/)
   (1)  Pascal add-on (pcode/)
@@ -1099,23 +1099,6 @@ o Libraries (libc/)
   Status:      Open
   Priority:    Low
 
-  Title:       FERROR()
-  Description: ferror(), feof(), and clearerror() are present, but the
-               implementation of ferror() is limited.  There are flags in the
-               stream structure to indicate EOF and error conditions but nothing
-               in the code currently sets the error indication.  This is a
-               trivial change to many interfaces and has not yet been done.
-               Instead, for now, ferror() is equivalent to !feof().  If an
-               interface can failure because of an error or and EOF and you
-               only want to distinguish between an error and the EOF then
-               this ferror() will work.  However, if no error is reported then
-               this ferror() cannot tell you if an error has occurred or not.
-  Status:      Open
-  Priority:    Meidum to Low:  Some applications use ferror() and not the
-               return value to determine if an error occurred.  Those
-               applications will fail with this limited implementation of
-               ferror().
-
   Title:       CONCURRENT STREAM READ/WRITE
   Description: NuttX only supports a single file pointer so reads and writes
                must be from the same position.  This prohibits implementation
diff --git a/nuttx/libc/stdio/lib_ferror.c b/nuttx/libc/stdio/lib_ferror.c
index a977394cb..4d324c808 100644
--- a/nuttx/libc/stdio/lib_ferror.c
+++ b/nuttx/libc/stdio/lib_ferror.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/stdio/lib_ferror.c
  *
- *   Copyright (C) 2012 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2012, 2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -64,26 +64,12 @@
 
 int ferror(FILE *stream)
 {
-#if 0
   /* If an error is encountered by any of the C-buffered I/O functions, they
    * should set the __FS_FLAG_ERROR in the fs_flags field of struct
    * file_struct.
    */
 
   return (stream->fs_flags & __FS_FLAG_ERROR) != 0;
-#else
-  /* However, nothing currenlty sets the __FS_FLAG_ERROR flag (that is a job
-   * for another day).  The __FS_FLAG_EOF is set by operations that perform
-   * read operations.  Since ferror()  is probably only called to disambiguate
-   * the meaning of other functions that return EOF, to indicate either EOF or
-   * an error, just testing for not EOF is probably sufficient for now.
-   *
-   * This approach would not work if ferror() is called in other contexts. In
-   * those cases, ferror() will always report an error.
-   */
-
-  return (stream->fs_flags & __FS_FLAG_EOF) == 0;
-#endif
 }
 
 #endif /* CONFIG_NFILE_STREAMS */
diff --git a/nuttx/libc/stdio/lib_fread.c b/nuttx/libc/stdio/lib_fread.c
index 4cdc19c0b..3bfac6995 100644
--- a/nuttx/libc/stdio/lib_fread.c
+++ b/nuttx/libc/stdio/lib_fread.c
@@ -45,7 +45,7 @@
 #include "lib_internal.h"
 
 /****************************************************************************
- * Definitions
+ * Pre-processor Definitions
  ****************************************************************************/
 
 /****************************************************************************
@@ -95,5 +95,6 @@ size_t fread(FAR void *ptr, size_t size, size_t n_items, FAR FILE *stream)
 
       items_read = bytes_read / size;
     }
+
   return items_read;
 }
diff --git a/nuttx/libc/stdio/lib_libfflush.c b/nuttx/libc/stdio/lib_libfflush.c
index 07b230b54..842de018a 100644
--- a/nuttx/libc/stdio/lib_libfflush.c
+++ b/nuttx/libc/stdio/lib_libfflush.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/stdio/lib_libfflush.c
  *
- *   Copyright (C) 2007-2008, 2011-2013 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2008, 2011-2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -34,10 +34,6 @@
  ****************************************************************************/
 
 /****************************************************************************
- * Compilation Switches
- ****************************************************************************/
-
-/****************************************************************************
  * Included Files
  ****************************************************************************/
 
@@ -54,7 +50,7 @@
 #include "lib_internal.h"
 
 /****************************************************************************
- * Definitions
+ * Pre-processor Definitions
  ****************************************************************************/
 
 /****************************************************************************
@@ -157,6 +153,7 @@ ssize_t lib_fflush(FAR FILE *stream, bool bforce)
                * returned the negated errno value.
                */
 
+              stream->fs_flags |= __FS_FLAG_ERROR;
               lib_give_semaphore(stream);
               return -get_errno();
             }
diff --git a/nuttx/libc/stdio/lib_libfread.c b/nuttx/libc/stdio/lib_libfread.c
index 08c5bd5f2..684f33b74 100644
--- a/nuttx/libc/stdio/lib_libfread.c
+++ b/nuttx/libc/stdio/lib_libfread.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/stdio/lib_libfread.c
  *
- *   Copyright (C) 2007-2009, 2011-2013 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2011-2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -37,7 +37,7 @@
  * Included Files
  ****************************************************************************/
 
-#include <nuttx/config.h>  /* for CONFIG_STDIO_BUFFER_SIZE */
+#include <nuttx/config.h>
 
 #include <sys/types.h>
 #include <stdio.h>
@@ -312,6 +312,7 @@ ssize_t lib_fread(FAR void *ptr, size_t count, FAR FILE *stream)
 /* Error exits */
 
 errout_with_errno:
+  stream->fs_flags |= __FS_FLAG_ERROR;
   lib_give_semaphore(stream);
   return -get_errno();
 }
diff --git a/nuttx/libc/stdio/lib_libfwrite.c b/nuttx/libc/stdio/lib_libfwrite.c
index e7443f996..ea75da6d7 100644
--- a/nuttx/libc/stdio/lib_libfwrite.c
+++ b/nuttx/libc/stdio/lib_libfwrite.c
@@ -1,7 +1,7 @@
 /****************************************************************************
  * libc/stdio/lib_libfwrite.c
  *
- *   Copyright (C) 2007-2009, 2011, 2013 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2011, 2013-2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -37,7 +37,7 @@
  * Included Files
  ****************************************************************************/
 
-#include <nuttx/config.h>  /* for CONFIG_STDIO_BUFFER_SIZE */
+#include <nuttx/config.h>
 
 #include <sys/types.h>
 #include <stdbool.h>
@@ -145,6 +145,7 @@ ssize_t lib_fwrite(FAR const void *ptr, size_t count, FAR FILE *stream)
         {
           *dest++ = *src++;
         }
+
       stream->fs_bufpos = dest;
 
       /* Is the buffer full? */
@@ -169,10 +170,21 @@ errout_with_semaphore:
   lib_give_semaphore(stream);
 
 errout:
+  if (ret < 0)
+    {
+      stream->fs_flags |= __FS_FLAG_ERROR;
+    }
+
   return ret;
 }
 #else
 {
-  return write(stream->fs_fd, ptr, count);
+  ssize_t ret = write(stream->fs_fd, ptr, count);
+  if (ret < 0)
+    {
+      stream->fs_flags |= __FS_FLAG_ERROR;
+    }
+
+  return ret;
 }
 #endif /* CONFIG_STDIO_BUFFER_SIZE */