[Libguestfs] [nbdkit PATCH] tests: Check that cache-min-block-size works properly

Signed-off-by: Martin Kletzander <mkletzan(a)redhat.com&gt; --- tests/test-cache-block-size.sh | 33 ++++++++++++++++++++++----------- 1 file changed, 22 insertions(+), 11 deletions(-) diff --git a/tests/test-cache-block-size.sh b/tests/test-cache-block-size.sh index d20cc94002b6..5e83ebc1cfaa 100755 --- a/tests/test-cache-block-size.sh +++ b/tests/test-cache-block-size.sh @@ -47,24 +47,35 @@ truncate -s 128K cache-block-size.img # Run nbdkit with the caching filter. start_nbdkit -P cache-block-size.pid -U $sock --filter=cache \ - file cache-block-size.img cache-min-block-size=4K + file cache-block-size.img cache-min-block-size=64K \ + cache-on-read=true nbdsh --connect "nbd+unix://?socket=$sock" \ -c ' -# Write some pattern data to the overlay and check it reads back OK. -buf = b"abcd" * 16384 -h.pwrite(buf, 32768) +# Read half of cache-min-block-size + zero = h.pread(32768, 0) assert zero == bytearray(32768) -buf2 = h.pread(65536, 32768) -assert buf == buf2 -# Flushing should write through to the underlying file. -h.flush() +buf = b"abcd" * 8192 +# Write past the first read +with open("cache-block-size.img", "wb") as file: + file.seek(32768) + file.write(buf * 2) + file.truncate(131072) + +# Check that it got written with open("cache-block-size.img", "rb") as file: - zero = file.read(32768) - assert zero == bytearray(32768) + file.seek(32768) buf2 = file.read(65536) - assert buf == buf2 + assert (buf * 2) == buf2 + +# Now read the rest of the cache-min-block-size, it should stay empty +zero = h.pread(32768, 32768) +assert zero == bytearray(32768) + +# Read past that, the pattern should be visible there +buf2 = h.pread(32768, 65536) +assert buf == buf2 ' -- 2.32.0