fs/vfs: file_write() and file_pwrite() are internal OS interfaces and should not report errors via the errno

fs/aio/aio_write.c

@@ -155,6 +155,13 @@ static void aio_write_worker(FAR void *arg)
                                  aiocbp->aio_nbytes,
                                  aiocbp->aio_offset);
         }
+
+      /* errno is not set */
+
+      if (nwritten < 0)
+        {
+          ferr("ERROR: file_write/file_pwrite failed: %d\n", nwritten);
+        }
     }
 #endif
 #if defined(AIO_HAVE_FILEP) && defined(AIO_HAVE_PSOCK)
@@ -172,22 +179,21 @@ static void aio_write_worker(FAR void *arg)
       nwritten = psock_send(aioc->u.aioc_psock,
                             (FAR const void *)aiocbp->aio_buf,
                             aiocbp->aio_nbytes, 0);
+      /* errno is set */
+
+      if (nwritten < 0)
+        {
+          int errcode = get_errno();
+          ferr("ERROR: psock_send failed: %d\n", errcode);
+          DEBUGASSERT(errcode > 0);
+          nwritten = -errcode;
+        }
     }
 #endif
 
-  /* Check the result of the write */
+  /* Save the result of the write */
 
-  if (nwritten < 0)
-    {
-      int errcode = get_errno();
-      ferr("ERROR: write/pwrite failed: %d\n", errcode);
-      DEBUGASSERT(errcode > 0);
-      aiocbp->aio_result = -errcode;
-    }
-  else
-    {
-      aiocbp->aio_result = nwritten;
-    }
+  aiocbp->aio_result = nwritten;
 
 #ifdef AIO_HAVE_FILEP
 errout:

fs/vfs/fs_pwrite.c

@@ -66,38 +66,32 @@ ssize_t file_pwrite(FAR struct file *filep, FAR const void *buf,
   off_t savepos;
   off_t pos;
   ssize_t ret;
-  int errcode = 0;
 
   /* Perform the seek to the current position.  This will not move the
    * file pointer, but will return its current setting
    */
 
   savepos = file_seek(filep, 0, SEEK_CUR);
-  if (savepos == (off_t)-1)
+  if (savepos < 0)
     {
       /* file_seek might fail if this if the media is not seekable */
 
-      return ERROR;
+      return (ssize_t)savepos;
     }
 
   /* Then seek to the correct position in the file */
 
   pos = file_seek(filep, offset, SEEK_SET);
-  if (pos == (off_t)-1)
+  if (pos < 0)
     {
       /* This might fail is the offset is beyond the end of file */
 
-      return ERROR;
+      return (ssize_t)pos;
     }
 
   /* Then perform the write operation */
 
   ret = file_write(filep, buf, nbytes);
-  if (ret < 0)
-    {
-      errcode = get_errno();
-      ret     = ERROR;
-    }
 
   /* Restore the file position */
 
@@ -106,13 +100,7 @@ ssize_t file_pwrite(FAR struct file *filep, FAR const void *buf,
     {
       /* This really should not fail */
 
-      errcode = -pos;
-      ret     = ERROR;
-    }
-
-  if (errcode != 0)
-    {
-      set_errno(errcode);
+      ret = (ssize_t)pos;
     }
 
   return ret;
@@ -168,6 +156,11 @@ ssize_t pwrite(int fd, FAR const void *buf, size_t nbytes, off_t offset)
       /* Let file_pread do the real work */
 
       ret = file_pwrite(filep, buf, nbytes, offset);
+      if (ret < 0)
+        {
+          set_errno((int)-ret);
+          ret = ERROR;
+        }
     }
 
   (void)enter_cancellation_point();

fs/vfs/fs_write.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * fs/vfs/fs_write.c
  *
- *   Copyright (C) 2007-2009, 2012-2014, 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2012-2014, 2016-2017 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -71,15 +71,12 @@
 ssize_t file_write(FAR struct file *filep, FAR const void *buf, size_t nbytes)
 {
   FAR struct inode *inode;
-  ssize_t ret;
-  int errcode;
 
   /* Was this file opened for write access? */
 
   if ((filep->f_oflags & O_WROK) == 0)
     {
-      errcode = EBADF;
-      goto errout;
+      return -EBADF;
     }
 
   /* Is a driver registered? Does it support the write method? */
@@ -87,24 +84,12 @@ ssize_t file_write(FAR struct file *filep, FAR const void *buf, size_t nbytes)
   inode = filep->f_inode;
   if (!inode || !inode->u.i_ops || !inode->u.i_ops->write)
     {
-      errcode = EBADF;
-      goto errout;
+      return -EBADF;
     }
 
   /* Yes, then let the driver perform the write */
 
-  ret = inode->u.i_ops->write(filep, buf, nbytes);
-  if (ret < 0)
-    {
-      errcode = -ret;
-      goto errout;
-    }
-
-  return ret;
-
-errout:
-  set_errno(errcode);
-  return ERROR;
+  return inode->u.i_ops->write(filep, buf, nbytes);
 }
 
 /****************************************************************************
@@ -208,6 +193,11 @@ ssize_t write(int fd, FAR const void *buf, size_t nbytes)
            */
 
           ret = file_write(filep, buf, nbytes);
+          if (ret < 0)
+            {
+              set_errno((int)-ret);
+              ret = ERROR;
+            }
         }
     }
 #endif