libio: remove precache from istream_advance_buffer

Since the user has to call istream_get_buffered_data afterwards anyway,
we can do the precache lazily.

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 1 insertions, 4 deletions

diff --git a/lib/io/test/istream_mem.c b/lib/io/test/istream_mem.c
index f1849dd..84da9a9 100644
--- a/lib/io/test/istream_mem.c
+++ b/lib/io/test/istream_mem.c
@@ -63,11 +63,8 @@ int main(int argc, char **argv)
 			TEST_EQUAL_UI(ptr[j], byte_at_offset(i + j));
 		}
 
-		diff = eat_all ? size : (size / 2);
+		istream_advance_buffer(in, eat_all ? size : (size / 2));
 		eat_all = !eat_all;
-
-		ret = istream_advance_buffer(in, diff);
-		TEST_EQUAL_I(ret, 0);
 	}
 
 	sqfs_drop(in);