commit 52d222aafbc21d674624fdd4c8fc834a40af69c7 Author: Nick Mathewson nickm@torproject.org Date: Thu Jan 9 12:47:24 2014 -0500

Add tests for buffer time tracking. --- src/common/compat_libevent.c | 14 +++++++- src/common/compat_libevent.h | 3 ++ src/test/test_buffers.c | 73 ++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 89 insertions(+), 1 deletion(-)

diff --git a/src/common/compat_libevent.c b/src/common/compat_libevent.c index 4d0fff8..b7987bc 100644 --- a/src/common/compat_libevent.c +++ b/src/common/compat_libevent.c @@ -626,7 +626,9 @@ tor_add_bufferevent_to_rate_limit_group(struct bufferevent *bev, } #endif

-#if defined(LIBEVENT_VERSION_NUMBER) && LIBEVENT_VERSION_NUMBER >= V(2,1,1) + +#if defined(LIBEVENT_VERSION_NUMBER) && LIBEVENT_VERSION_NUMBER >= V(2,1,1) \ + && !defined(TOR_UNIT_TESTS) void tor_gettimeofday_cached(struct timeval *tv) { @@ -659,5 +661,15 @@ tor_gettimeofday_cache_clear(void) { cached_time_hires.tv_sec = 0; } + +#ifdef TOR_UNIT_TESTS +/** For testing: force-update the cached time to a given value. */ +void +tor_gettimeofday_cache_set(const struct timeval *tv) +{ + tor_assert(tv); + memcpy(&cached_time_hires, tv, sizeof(*tv)); +} +#endif #endif

diff --git a/src/common/compat_libevent.h b/src/common/compat_libevent.h index fda8733..17e0523 100644 --- a/src/common/compat_libevent.h +++ b/src/common/compat_libevent.h @@ -91,6 +91,9 @@ int tor_add_bufferevent_to_rate_limit_group(struct bufferevent *bev,

void tor_gettimeofday_cached(struct timeval *tv); void tor_gettimeofday_cache_clear(void); +#ifdef TOR_UNIT_TESTS +void tor_gettimeofday_cache_set(const struct timeval *tv); +#endif

#endif

diff --git a/src/test/test_buffers.c b/src/test/test_buffers.c index ab1e5df..a410770 100644 --- a/src/test/test_buffers.c +++ b/src/test/test_buffers.c @@ -516,6 +516,78 @@ test_buffer_allocation_tracking(void *arg) buf_shrink_freelists(1); }

+static void +test_buffer_time_tracking(void *arg) +{ + buf_t *buf=NULL, *buf2=NULL; + struct timeval tv0; + const time_t START = 1389288246; + const uint32_t START_MSEC = (uint32_t) ((uint64_t)START * 1000); + int i; + char tmp[4096]; + (void)arg; + + crypto_rand(tmp, sizeof(tmp)); + + tv0.tv_sec = START; + tv0.tv_usec = 0; + + buf = buf_new_with_capacity(3000); /* rounds up to next power of 2. */ + tt_assert(buf); + + /* Empty buffer means the timestamp is 0. */ + tt_int_op(0, ==, buf_get_oldest_chunk_timestamp(buf, START_MSEC)); + tt_int_op(0, ==, buf_get_oldest_chunk_timestamp(buf, START_MSEC+1000)); + + tor_gettimeofday_cache_set(&tv0); + write_to_buf("ABCDEFG", 7, buf); + tt_int_op(1000, ==, buf_get_oldest_chunk_timestamp(buf, START_MSEC+1000)); + + buf2 = buf_copy(buf); + tt_assert(buf2); + tt_int_op(1234, ==, buf_get_oldest_chunk_timestamp(buf2, START_MSEC+1234)); + + /* Now add more bytes; enough to overflow the first chunk. */ + tv0.tv_usec += 123 * 1000; + tor_gettimeofday_cache_set(&tv0); + for (i = 0; i < 600; ++i) + write_to_buf("ABCDEFG", 7, buf); + tt_int_op(4207, ==, buf_datalen(buf)); + + /* The oldest bytes are still in the front. */ + tt_int_op(2000, ==, buf_get_oldest_chunk_timestamp(buf, START_MSEC+2000)); + + /* Once those bytes are dropped, the chunk is still on the first + * timestamp. */ + fetch_from_buf(tmp, 100, buf); + tt_int_op(2000, ==, buf_get_oldest_chunk_timestamp(buf, START_MSEC+2000)); + + /* But once we discard the whole first chunk, we get the data in the second + * chunk. */ + fetch_from_buf(tmp, 4000, buf); + tt_int_op(107, ==, buf_datalen(buf)); + tt_int_op(2000, ==, buf_get_oldest_chunk_timestamp(buf, START_MSEC+2123)); + + /* This time we'll be grabbing a chunk from the freelist, and making sure + its time gets updated */ + tv0.tv_sec += 5; + tv0.tv_usec = 617*1000; + tor_gettimeofday_cache_set(&tv0); + for (i = 0; i < 600; ++i) + write_to_buf("ABCDEFG", 7, buf); + tt_int_op(4307, ==, buf_datalen(buf)); + + tt_int_op(2000, ==, buf_get_oldest_chunk_timestamp(buf, START_MSEC+2123)); + fetch_from_buf(tmp, 4000, buf); + fetch_from_buf(tmp, 306, buf); + tt_int_op(0, ==, buf_get_oldest_chunk_timestamp(buf, START_MSEC+5617)); + tt_int_op(383, ==, buf_get_oldest_chunk_timestamp(buf, START_MSEC+6000)); + + done: + buf_free(buf); + buf_free(buf2); +} + struct testcase_t buffer_tests[] = { { "basic", test_buffers_basic, TT_FORK, NULL, NULL }, { "copy", test_buffer_copy, TT_FORK, NULL, NULL }, @@ -523,6 +595,7 @@ struct testcase_t buffer_tests[] = { { "ext_or_cmd", test_buffer_ext_or_cmd, TT_FORK, NULL, NULL }, { "allocation_tracking", test_buffer_allocation_tracking, TT_FORK, NULL, NULL }, + { "time_tracking", test_buffer_time_tracking, TT_FORK, NULL, NULL }, END_OF_TESTCASES };