linux: Only set errno after an error

errno is only valid after an error, and was being filled with a garbage
value upon eof.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>

1 files changed, 6 insertions, 2 deletions

diff --git a/src/linux_sysfs.c b/src/linux_sysfs.c
index 1832ee7..bbd4dfa 100644
--- a/src/linux_sysfs.c
+++ b/src/linux_sysfs.c
@@ -387,7 +387,9 @@ pci_device_linux_sysfs_read( struct pci_device * dev, void * data,
 	/* If zero bytes were read, then we assume it's the end of the
 	 * config file.
 	 */
-	if ( bytes <= 0 ) {
+	if (bytes == 0)
+	    break;
+	if ( bytes < 0 ) {
 	    err = errno;
 	    break;
 	}
@@ -445,7 +447,9 @@ pci_device_linux_sysfs_write( struct pci_device * dev, const void * data,
 	/* If zero bytes were written, then we assume it's the end of the
 	 * config file.
 	 */
-	if ( bytes <= 0 ) {
+	if ( bytes == 0 )
+	    break;
+	if ( bytes < 0 ) {
 	    err = errno;
 	    break;
 	}