return errors properly in comedi_mark_buffer_read() and

comedi_mark_buffer_written()

diff --git a/lib/buffer.c b/lib/buffer.c
index a3d70b3a1f19fcb2a4fc1e6f8b3d52d2e6188920..9ebe9f25dd632182201cc32c109a109c04141441 100644 (file)
--- a/lib/buffer.c
+++ b/lib/buffer.c
@@ -84,8 +84,12 @@ int _comedi_mark_buffer_read(comedi_t *it, unsigned int subdev, unsigned int byt
        bi.subdevice = subdev;
        bi.bytes_read = bytes;
        ret = comedi_ioctl(it->fd, COMEDI_BUFINFO, (unsigned long)&bi);
-       __comedi_errno = errno;
-       if(__comedi_errno == EPIPE)__comedi_errno = EBUF_OVR;
+       if(ret < 0)
+       {
+               __comedi_errno = errno;
+               if(__comedi_errno == EPIPE)__comedi_errno = EBUF_OVR;
+               return ret;
+       }
        return bi.buf_write_count - bi.buf_read_count;
 }
 
@@ -99,8 +103,12 @@ int _comedi_mark_buffer_written(comedi_t *it, unsigned int subdev, unsigned int
        bi.subdevice = subdev;
        bi.bytes_written = bytes;
        ret = comedi_ioctl(it->fd, COMEDI_BUFINFO, (unsigned long)&bi);
-       __comedi_errno = errno;
-       if(__comedi_errno == EPIPE)__comedi_errno = EBUF_UNDR;
+       if(ret < 0)
+       {
+               __comedi_errno = errno;
+               if(__comedi_errno == EPIPE)__comedi_errno = EBUF_UNDR;
+               return ret;
+       }
        return bi.buf_write_count - bi.buf_read_count;
 }