The unit tests contain a lot of duplicated code and here's an attempt
to reduce code duplication.
This commit does several things:
1. Remove #ifdef HAVE_CMOCKA - we already solve this with automake
conditionals.
2. Create a set of ISC_TEST_* and ISC_*_TEST_ macros to wrap the test
implementations, test lists, and the main test routine, so we don't
have to repeat this all over again. The macros were modeled after
libuv test suite but adapted to cmocka as the test driver.
A simple example of a unit test would be:
ISC_RUN_TEST_IMPL(test1) { assert_true(true); }
ISC_TEST_LIST_START
ISC_TEST_ENTRY(test1)
ISC_TEST_LIST_END
ISC_TEST_MAIN (Discussion: Should this be ISC_TEST_RUN ?)
For more complicated examples including group setup and teardown
functions, and per-test setup and teardown functions.
3. The macros prefix the test functions and cmocka entries, so the name
of the test can now match the tested function name, and we don't have
to append `_test` because `run_test_` is automatically prepended to
the main test function, and `setup_test_` and `teardown_test_` is
prepended to setup and teardown function.
4. Update all the unit tests to use the new syntax and fix a few bits
here and there.
5. In the future, we can separate the test declarations and test
implementations which are going to greatly help with uncluttering the
bigger unit tests like doh_test and netmgr_test, because the test
implementations are not declared static (see `ISC_RUN_TEST_DECLARE`
and `ISC_RUN_TEST_IMPL` for more details.
NOTE: This heavily relies on preprocessor macros, but the result greatly
outweighs all the negatives of using the macros. There's less
duplicated code, the tests are more uniform and the implementation can
be more flexible.
Instead of passing the number of worker to the dns_zonemgr manually,
get the number of nm threads using the new isc_nm_getnworkers() call.
Additionally, remove the isc_pool API and manage the array of memory
context, zonetasks and loadtasks directly in the zonemgr.
Previously, the zonemgr created 1 task per 100 zones and 1 memory
context per 1000 zones (with minimum 10 tasks and 2 memory contexts) to
reduce the contention between threads.
Instead of reducing the contention by having many resources, create a
per-nm_thread memory context, loadtask and zonetask and spread the zones
between just per-thread resources.
Note: this commit alone does decrease performance when loading the zone
by couple seconds (in case of 1M zone) and thus there's more work in
this whole MR fixing the performance.
This commit converts the license handling to adhere to the REUSE
specification. It specifically:
1. Adds used licnses to LICENSES/ directory
2. Add "isc" template for adding the copyright boilerplate
3. Changes all source files to include copyright and SPDX license
header, this includes all the C sources, documentation, zone files,
configuration files. There are notes in the doc/dev/copyrights file
on how to add correct headers to the new files.
4. Handle the rest that can't be modified via .reuse/dep5 file. The
binary (or otherwise unmodifiable) files could have license places
next to them in <foo>.license file, but this would lead to cluttered
repository and most of the files handled in the .reuse/dep5 file are
system test files.
- disp_connected() has been split into two functions,
udp_connected() (which takes 'resp' as an argument) and
tcp_connected() (which takes 'disp', and calls the connect callbacks
for all pending resps).
- In dns_dispatch_connect(), if a connection is already open, we need to
detach the dispentry immediately because we won't be running
tcp_connected().
- dns_disptach_cancel() also now calls the connect callbacks for pending
TCP responses, and the response callbacks for open TCP connections
waiting on read.
- If udp_connected() runs after dns_dispatch_cancel() has been called,
ensure that the caller's connect callback is run.
- If a UDP connection fails with EADDRINUSE, we try again up to five
times with a different local port number before giving up.
- If a TCP connection is canceled while still pending connection, the
connect timeout may still fire. we attach the dispatch before
connecting to ensure that it won't be detached too soon in this case.
- The dispentry is no longer removed from the pending list when
deactivating, so that the connect callback can still be run if
dns_dispatch_removeresponse() was run while the connecting was
pending.
- Rewrote dns_dispatch_gettcp() to avoid a data race.
- startrecv() and dispatch_getnext() can be called with a NULL resp when
using TCP.
- Refactored udp_recv() and tcp_recv() and added result logging.
- EOF is now treated the same as CANCELED in response callbacks.
- ISC_R_SHUTTINGDOWN is sent to the reponse callbacks for all resps if
tcp_recv() is triggered by a netmgr shutdown. (response callbacks
are *not* sent by udp_recv() in this case.)
All unit tests define the UNIT_TESTING macro, which causes <cmocka.h> to
replace malloc(), calloc(), realloc(), and free() with its own functions
tracking memory allocations. In order for this not to break
compilation, the system header declaring the prototypes for these
standard functions must be included before <cmocka.h>.
Normally, these prototypes are only present in <stdlib.h>, so we make
sure it is included before <cmocka.h>. However, musl libc also defines
the prototypes for calloc() and free() in <sched.h>, which is included
by <pthread.h>, which is included e.g. by <isc/mutex.h>. Thus, unit
tests including "dnstest.h" (which includes <isc/mem.h>, which includes
<isc/mutex.h>) after <cmocka.h> will not compile with musl libc as for
these programs, <sched.h> will be included after <cmocka.h>.
Always including <cmocka.h> after all other header files is not a
feasible solution as that causes the mock assertion macros defined in
<isc/util.h> to mangle the contents of <cmocka.h>, thus breaking
compilation. We cannot really use the __noreturn__ or analyzer_noreturn
attributes with cmocka assertion functions because they do return if the
tested condition is true. The problem is that what BIND unit tests do
is incompatible with Clang Static Analyzer's assumptions: since we use
cmocka, our custom assertion handlers are present in a shared library
(i.e. it is the cmocka library that checks the assertion condition, not
a macro in unit test code). Redefining cmocka's assertion macros in
<isc/util.h> is an ugly hack to overcome that problem - unfortunately,
this is the only way we can think of to make Clang Static Analyzer
properly process unit test code. Giving up on Clang Static Analyzer
being able to properly process unit test code is not a satisfactory
solution.
Undefining _GNU_SOURCE for unit test code could work around the problem
(musl libc's <sched.h> only defines the prototypes for calloc() and
free() when _GNU_SOURCE is defined), but doing that could introduce
discrepancies for unit tests including entire *.c files, so it is also
not a good solution.
All in all, including <sched.h> before <cmocka.h> for all affected unit
tests seems to be the most benign way of working around this musl libc
quirk. While quite an ugly solution, it achieves our goals here, which
are to keep the benefit of proper static analysis of unit test code and
to fix compilation against musl libc.
The common construct seen in the BIND 9 source is func(isc_mem_t *mctx, ...).
Unfortunately, the dnstest.{h,c} has been using mctx as a global symbol, which
in turn generated a lot of errors when update.c got included in update_test.c.
As a rule of thumb, we should avoid naming global symbols with generic names
(like mctx) and we should prefix them with "namespace" (like dt_mctx).
