fs/vfs: file_read() is an internal OS interface and should not errors via the errno

configs/nucleo-f4x1re/src/stm32_ajoystick.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/nucleo-f3x1re/src/stm32_ajoystick.c
  *
- *   Copyright (C) 2014, 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 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
@@ -210,13 +210,12 @@ static int ajoy_sample(FAR const struct ajoy_lowerhalf_s *lower,
                     MAX_ADC_CHANNELS * sizeof(struct adc_msg_s));
   if (nread < 0)
     {
-      int errcode = get_errno();
+      if (nread != -EINTR)
-      if (errcode != EINTR)
         {
-          ierr("ERROR: read failed: %d\n", errcode);
+          ierr("ERROR: read failed: %d\n", (int)nread);
         }
 
-      return -errcode;
+      return nread;
     }
   else if (nread < NJOYSTICK_CHANNELS * sizeof(struct adc_msg_s))
     {

configs/nucleo-l476rg/src/stm32_ajoystick.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * configs/nucleo-l476rg/src/stm32_ajoystick.c
  *
- *   Copyright (C) 2014, 2016 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 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
@@ -209,13 +209,12 @@ static int ajoy_sample(FAR const struct ajoy_lowerhalf_s *lower,
                     MAX_ADC_CHANNELS * sizeof(struct adc_msg_s));
   if (nread < 0)
     {
-      int errcode = get_errno();
+      if (nread != -EINTR)
-      if (errcode != EINTR)
         {
-          ierr("ERROR: read failed: %d\n", errcode);
+          ierr("ERROR: read failed: %d\n", (int)nread);
         }
 
-      return -errcode;
+      return nread;
     }
   else if (nread < NJOYSTICK_CHANNELS * sizeof(struct adc_msg_s))
     {

configs/sama5d3-xplained/src/sam_ajoystick.c

@@ -191,13 +191,12 @@ static int ajoy_sample(FAR const struct ajoy_lowerhalf_s *lower,
                     MAX_ADC_CHANNELS * sizeof(struct adc_msg_s));
   if (nread < 0)
     {
-      int errcode = get_errno();
+      if (nread != iEINTR)
-      if (errcode != EINTR)
         {
-          ierr("ERROR: read failed: %d\n", errcode);
+          ierr("ERROR: read failed: %d\n", (int)nread);
         }
 
-      return -errcode;
+      return nread;
     }
   else if (nread < 2 * sizeof(struct adc_msg_s))
     {

fs/vfs/fs_pread.c

@@ -95,7 +95,7 @@ ssize_t file_pread(FAR struct file *filep, FAR void *buf, size_t nbytes,
   ret = file_read(filep, buf, nbytes);
   if (ret < 0)
     {
-      errcode = get_errno();
+      errcode = -ret;
       ret     = ERROR;
     }
 

fs/vfs/fs_read.c

@@ -1,7 +1,7 @@
 /****************************************************************************
  * fs/vfs/fs_read.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
@@ -102,15 +102,7 @@ ssize_t file_read(FAR struct file *filep, FAR void *buf, size_t nbytes)
       ret = (int)inode->u.i_ops->read(filep, (FAR char *)buf, (size_t)nbytes);
     }
 
-  /* If an error occurred, set errno and return -1 (ERROR) */
+  /* Return the number of bytes read (or possibly an error code) */
-
-  if (ret < 0)
-    {
-      set_errno(-ret);
-      return ERROR;
-    }
-
-  /* Otherwise, return the number of bytes read */
 
   return ret;
 }
@@ -180,11 +172,14 @@ ssize_t read(int fd, FAR void *buf, size_t nbytes)
         }
       else
         {
-          /* Then let file_read do all of the work.  Note that file_read()
+          /* Then let file_read do all of the work. */
-           * sets the errno variable.
-           */
 
           ret = file_read(filep, buf, nbytes);
+          if (ret < 0)
+            {
+              set_errno((int)-ret);
+              ret = ERROR;
+            }
         }
     }
 #endif

net/tcp/tcp_sendfile.c

@@ -402,9 +402,8 @@ static uint16_t sendfile_eventhandler(FAR struct net_driver_s *dev,
           ret = file_read(pstate->snd_file, dev->d_appdata, sndlen);
           if (ret < 0)
             {
-              int errcode = get_errno();
+              nerr("ERROR: Failed to read from input file: %d\n", (int)ret);
-              nerr("ERROR: Failed to read from input file: %d\n", errcode);
+              pstate->snd_sent = ret;
-              pstate->snd_sent = -errcode;
               goto end_wait;
             }