Revert "oauth: Add unit tests for multiplexer handling"

Commit 1443b6c0e introduced buildfarm breakage for Autoconf animals,
which expect to be able to run `make installcheck` on the libpq-oauth
directory even if libcurl support is disabled. Some other Meson animals
complained of a missing -lm link as well.

Since this is the day before a freeze, revert for now and come back
later.

Discussion: https://postgr.es/m/CAOYmi%2BnCkoh3zB%2BGkZad44%3DFNskwUg6F1kmuxqQZzng7Zgj5tw%40mail.gmail.com

4 files changed, 0 insertions, 600 deletions

diff --git a/src/interfaces/libpq-oauth/Makefile b/src/interfaces/libpq-oauth/Makefile
index e73573694b9..682f17413b3 100644
--- a/src/interfaces/libpq-oauth/Makefile
+++ b/src/interfaces/libpq-oauth/Makefile
@@ -79,19 +79,5 @@ uninstall:
 	rm -f '$(DESTDIR)$(libdir)/$(stlib)'
 	rm -f '$(DESTDIR)$(libdir)/$(shlib)'
 
-.PHONY: all-tests
-all-tests: oauth_tests$(X)
-
-oauth_tests$(X): test-oauth-curl.o oauth-utils.o $(WIN32RES) | submake-libpgport submake-libpq
-	$(CC) $(CFLAGS) $^ $(LDFLAGS) $(LDFLAGS_EX) $(SHLIB_LINK) -o $@
-
-check: all-tests
-	$(prove_check)
-
-installcheck: all-tests
-	$(prove_installcheck)
-
 clean distclean: clean-lib
 	rm -f $(OBJS) $(OBJS_STATIC) $(OBJS_SHLIB)
-	rm -f test-oauth-curl.o oauth_tests$(X)
-	rm -rf tmp_check
diff --git a/src/interfaces/libpq-oauth/meson.build b/src/interfaces/libpq-oauth/meson.build
index 505e1671b86..df064c59a40 100644
--- a/src/interfaces/libpq-oauth/meson.build
+++ b/src/interfaces/libpq-oauth/meson.build
@@ -47,38 +47,3 @@ libpq_oauth_so = shared_module(libpq_oauth_name,
   link_args: export_fmt.format(export_file.full_path()),
   kwargs: default_lib_args,
 )
-
-libpq_oauth_test_deps = []
-
-oauth_test_sources = files('test-oauth-curl.c') + libpq_oauth_so_sources
-
-if host_system == 'windows'
-  oauth_test_sources += rc_bin_gen.process(win32ver_rc, extra_args: [
-    '--NAME', 'oauth_tests',
-    '--FILEDESC', 'OAuth unit test program',])
-endif
-
-libpq_oauth_test_deps += executable('oauth_tests',
-  oauth_test_sources,
-  dependencies: [frontend_shlib_code, libpq, libpq_oauth_deps],
-  kwargs: default_bin_args + {
-    'c_args': default_bin_args.get('c_args', []) + libpq_oauth_so_c_args,
-    'c_pch': pch_postgres_fe_h,
-    'include_directories': [libpq_inc, postgres_inc],
-    'install': false,
-  }
-)
-
-testprep_targets += libpq_oauth_test_deps
-
-tests += {
-  'name': 'libpq-oauth',
-  'sd': meson.current_source_dir(),
-  'bd': meson.current_build_dir(),
-  'tap': {
-    'tests': [
-      't/001_oauth.pl',
-    ],
-    'deps': libpq_oauth_test_deps,
-  },
-}
diff --git a/src/interfaces/libpq-oauth/t/001_oauth.pl b/src/interfaces/libpq-oauth/t/001_oauth.pl
deleted file mode 100644
index 5af6c860768..00000000000
--- a/src/interfaces/libpq-oauth/t/001_oauth.pl
+++ /dev/null
@@ -1,24 +0,0 @@
-# Copyright (c) 2025, PostgreSQL Global Development Group
-use strict;
-use warnings FATAL => 'all';
-
-use PostgreSQL::Test::Utils;
-use Test::More;
-
-# Defer entirely to the oauth_tests executable. stdout/err is routed through
-# Test::More so that our logging infrastructure can handle it correctly. Using
-# IPC::Run::new_chunker seems to help interleave the two streams a little better
-# than without.
-#
-# TODO: prove can also deal with native executables itself, which we could
-# probably make use of via PROVE_TESTS on the Makefile side. But the Meson setup
-# calls Perl directly, which would require more code to work around... and
-# there's still the matter of logging.
-my $builder = Test::More->builder;
-my $out = $builder->output;
-my $err = $builder->failure_output;
-
-IPC::Run::run ['oauth_tests'],
-  '>', IPC::Run::new_chunker, sub { $out->print($_[0]) },
-  '2>', IPC::Run::new_chunker, sub { $err->print($_[0]) }
-  or die "oauth_tests returned $?";
diff --git a/src/interfaces/libpq-oauth/test-oauth-curl.c b/src/interfaces/libpq-oauth/test-oauth-curl.c
deleted file mode 100644
index 8263aff2f4a..00000000000
--- a/src/interfaces/libpq-oauth/test-oauth-curl.c
+++ /dev/null
@@ -1,527 +0,0 @@
-/*
- * test-oauth-curl.c
- *
- * A unit test driver for libpq-oauth. This #includes oauth-curl.c, which lets
- * the tests reference static functions and other internals.
- *
- * USE_ASSERT_CHECKING is required, to make it easy for tests to wrap
- * must-succeed code as part of test setup.
- *
- * Copyright (c) 2025, PostgreSQL Global Development Group
- */
-
-#include "oauth-curl.c"
-
-#include <fcntl.h>
-
-#ifdef USE_ASSERT_CHECKING
-
-/*
- * TAP Helpers
- */
-
-static int	num_tests = 0;
-
-/*
- * Reports ok/not ok to the TAP stream on stdout.
- */
-#define ok(OK, TEST) \
-	ok_impl(OK, TEST, #OK, __FILE__, __LINE__)
-
-static bool
-ok_impl(bool ok, const char *test, const char *teststr, const char *file, int line)
-{
-	printf("%sok %d - %s\n", ok ? "" : "not ", ++num_tests, test);
-
-	if (!ok)
-	{
-		printf("# at %s:%d:\n", file, line);
-		printf("#   expression is false: %s\n", teststr);
-	}
-
-	return ok;
-}
-
-/*
- * Like ok(this == that), but with more diagnostics on failure.
- *
- * Only works on ints, but luckily that's all we need here. Note that the much
- * simpler-looking macro implementation
- *
- *     is_diag(ok(THIS == THAT, TEST), THIS, #THIS, THAT, #THAT)
- *
- * suffers from multiple evaluation of the macro arguments...
- */
-#define is(THIS, THAT, TEST) \
-	do { \
-		int this_ = (THIS), \
-			that_ = (THAT); \
-		is_diag( \
-			ok_impl(this_ == that_, TEST, #THIS " == " #THAT, __FILE__, __LINE__), \
-			this_, #THIS, that_, #THAT \
-		); \
-	} while (0)
-
-static bool
-is_diag(bool ok, int this, const char *thisstr, int that, const char *thatstr)
-{
-	if (!ok)
-		printf("#   %s = %d; %s = %d\n", thisstr, this, thatstr, that);
-
-	return ok;
-}
-
-/*
- * Utilities
- */
-
-/*
- * Creates a partially-initialized async_ctx for the purposes of testing. Free
- * with free_test_actx().
- */
-static struct async_ctx *
-init_test_actx(void)
-{
-	struct async_ctx *actx;
-
-	actx = calloc(1, sizeof(*actx));
-	Assert(actx);
-
-	actx->mux = PGINVALID_SOCKET;
-	actx->timerfd = -1;
-	actx->debugging = true;
-
-	initPQExpBuffer(&actx->errbuf);
-
-	Assert(setup_multiplexer(actx));
-
-	return actx;
-}
-
-static void
-free_test_actx(struct async_ctx *actx)
-{
-	termPQExpBuffer(&actx->errbuf);
-
-	if (actx->mux != PGINVALID_SOCKET)
-		close(actx->mux);
-	if (actx->timerfd >= 0)
-		close(actx->timerfd);
-
-	free(actx);
-}
-
-static char dummy_buf[4 * 1024];	/* for fill_pipe/drain_pipe */
-
-/*
- * Writes to the write side of a pipe until it won't take any more data. Returns
- * the amount written.
- */
-static ssize_t
-fill_pipe(int fd)
-{
-	int			mode;
-	ssize_t		written = 0;
-
-	/* Don't block. */
-	Assert((mode = fcntl(fd, F_GETFL)) != -1);
-	Assert(fcntl(fd, F_SETFL, mode | O_NONBLOCK) == 0);
-
-	while (true)
-	{
-		ssize_t		w;
-
-		w = write(fd, dummy_buf, sizeof(dummy_buf));
-		if (w < 0)
-		{
-			if (errno != EAGAIN && errno != EWOULDBLOCK)
-			{
-				perror("write to pipe");
-				written = -1;
-			}
-			break;
-		}
-
-		written += w;
-	}
-
-	/* Reset the descriptor flags. */
-	Assert(fcntl(fd, F_SETFD, mode) == 0);
-
-	return written;
-}
-
-/*
- * Drains the requested amount of data from the read side of a pipe.
- */
-static bool
-drain_pipe(int fd, ssize_t n)
-{
-	Assert(n > 0);
-
-	while (n)
-	{
-		size_t		to_read = (n <= sizeof(dummy_buf)) ? n : sizeof(dummy_buf);
-		ssize_t		drained;
-
-		drained = read(fd, dummy_buf, to_read);
-		if (drained < 0)
-		{
-			perror("read from pipe");
-			return false;
-		}
-
-		n -= drained;
-	}
-
-	return true;
-}
-
-/*
- * Tests whether the multiplexer is marked ready by the deadline. This is a
- * macro so that file/line information makes sense during failures.
- *
- * NB: our current multiplexer implementations (epoll/kqueue) are *readable*
- * when the underlying libcurl sockets are *writable*. This behavior is pinned
- * here to record that expectation; PGRES_POLLING_READING is hardcoded
- * throughout the flow and would need to be changed if a new multiplexer does
- * something different.
- */
-#define mux_is_ready(MUX, DEADLINE, TEST) \
-	do { \
-		int res_ = PQsocketPoll(MUX, 1, 0, DEADLINE); \
-		Assert(res_ != -1); \
-		ok(res_ > 0, "multiplexer is ready " TEST); \
-	} while (0)
-
-/*
- * The opposite of mux_is_ready().
- */
-#define mux_is_not_ready(MUX, TEST) \
-	do { \
-		int res_ = PQsocketPoll(MUX, 1, 0, 0); \
-		Assert(res_ != -1); \
-		is(res_, 0, "multiplexer is not ready " TEST); \
-	} while (0)
-
-/*
- * Test Suites
- */
-
-/* Per-suite timeout. Set via the PG_TEST_TIMEOUT_DEFAULT envvar. */
-static pg_usec_time_t timeout_us = 180 * 1000 * 1000;
-
-static void
-test_set_timer(void)
-{
-	struct async_ctx *actx = init_test_actx();
-	const pg_usec_time_t deadline = PQgetCurrentTimeUSec() + timeout_us;
-
-	printf("# test_set_timer\n");
-
-	/* A zero-duration timer should result in a near-immediate ready signal. */
-	Assert(set_timer(actx, 0));
-	mux_is_ready(actx->mux, deadline, "when timer expires");
-	is(timer_expired(actx), 1, "timer_expired() returns 1 when timer expires");
-
-	/* Resetting the timer far in the future should unset the ready signal. */
-	Assert(set_timer(actx, INT_MAX));
-	mux_is_not_ready(actx->mux, "when timer is reset to the future");
-	is(timer_expired(actx), 0, "timer_expired() returns 0 with unexpired timer");
-
-	/* Setting another zero-duration timer should override the previous one. */
-	Assert(set_timer(actx, 0));
-	mux_is_ready(actx->mux, deadline, "when timer is re-expired");
-	is(timer_expired(actx), 1, "timer_expired() returns 1 when timer is re-expired");
-
-	/* And disabling that timer should once again unset the ready signal. */
-	Assert(set_timer(actx, -1));
-	mux_is_not_ready(actx->mux, "when timer is unset");
-	is(timer_expired(actx), 0, "timer_expired() returns 0 when timer is unset");
-
-	{
-		bool		expired;
-
-		/* Make sure drain_timer_events() functions correctly as well. */
-		Assert(set_timer(actx, 0));
-		mux_is_ready(actx->mux, deadline, "when timer is re-expired (drain_timer_events)");
-
-		Assert(drain_timer_events(actx, &expired));
-		mux_is_not_ready(actx->mux, "when timer is drained after expiring");
-		is(expired, 1, "drain_timer_events() reports expiration");
-		is(timer_expired(actx), 0, "timer_expired() returns 0 after timer is drained");
-
-		/* A second drain should do nothing. */
-		Assert(drain_timer_events(actx, &expired));
-		mux_is_not_ready(actx->mux, "when timer is drained a second time");
-		is(expired, 0, "drain_timer_events() reports no expiration");
-		is(timer_expired(actx), 0, "timer_expired() still returns 0");
-	}
-
-	free_test_actx(actx);
-}
-
-static void
-test_register_socket(void)
-{
-	struct async_ctx *actx = init_test_actx();
-	int			pipefd[2];
-	int			rfd,
-				wfd;
-	bool		bidirectional;
-
-	/* Create a local pipe for communication. */
-	Assert(pipe(pipefd) == 0);
-	rfd = pipefd[0];
-	wfd = pipefd[1];
-
-	/*
-	 * Some platforms (FreeBSD) implement bidirectional pipes, affecting the
-	 * behavior of some of these tests. Store that knowledge for later.
-	 */
-	bidirectional = PQsocketPoll(rfd /* read */ , 0, 1 /* write */ , 0) > 0;
-
-	/*
-	 * This suite runs twice -- once using CURL_POLL_IN/CURL_POLL_OUT for
-	 * read/write operations, respectively, and once using CURL_POLL_INOUT for
-	 * both sides.
-	 */
-	for (int inout = 0; inout < 2; inout++)
-	{
-		const int	in_event = inout ? CURL_POLL_INOUT : CURL_POLL_IN;
-		const int	out_event = inout ? CURL_POLL_INOUT : CURL_POLL_OUT;
-		const pg_usec_time_t deadline = PQgetCurrentTimeUSec() + timeout_us;
-		size_t		bidi_pipe_size = 0; /* silence compiler warnings */
-
-		printf("# test_register_socket %s\n", inout ? "(INOUT)" : "");
-
-		/*
-		 * At the start of the test, the read side should be blocked and the
-		 * write side should be open. (There's a mistake at the end of this
-		 * loop otherwise.)
-		 */
-		Assert(PQsocketPoll(rfd, 1, 0, 0) == 0);
-		Assert(PQsocketPoll(wfd, 0, 1, 0) > 0);
-
-		/*
-		 * For bidirectional systems, emulate unidirectional behavior here by
-		 * filling up the "read side" of the pipe.
-		 */
-		if (bidirectional)
-			Assert((bidi_pipe_size = fill_pipe(rfd)) > 0);
-
-		/* Listen on the read side. The multiplexer shouldn't be ready yet. */
-		Assert(register_socket(NULL, rfd, in_event, actx, NULL) == 0);
-		mux_is_not_ready(actx->mux, "when fd is not readable");
-
-		/* Writing to the pipe should result in a read-ready multiplexer. */
-		Assert(write(wfd, "x", 1) == 1);
-		mux_is_ready(actx->mux, deadline, "when fd is readable");
-
-		/*
-		 * Update the registration to wait on write events instead. The
-		 * multiplexer should be unset.
-		 */
-		Assert(register_socket(NULL, rfd, CURL_POLL_OUT, actx, NULL) == 0);
-		mux_is_not_ready(actx->mux, "when waiting for writes on readable fd");
-
-		/* Re-register for read events. */
-		Assert(register_socket(NULL, rfd, in_event, actx, NULL) == 0);
-		mux_is_ready(actx->mux, deadline, "when waiting for reads again");
-
-		/* Stop listening. The multiplexer should be unset. */
-		Assert(register_socket(NULL, rfd, CURL_POLL_REMOVE, actx, NULL) == 0);
-		mux_is_not_ready(actx->mux, "when readable fd is removed");
-
-		/* Listen again. */
-		Assert(register_socket(NULL, rfd, in_event, actx, NULL) == 0);
-		mux_is_ready(actx->mux, deadline, "when readable fd is re-added");
-
-		/*
-		 * Draining the pipe should unset the multiplexer again, once the old
-		 * event is cleared.
-		 */
-		Assert(drain_pipe(rfd, 1));
-		Assert(comb_multiplexer(actx));
-		mux_is_not_ready(actx->mux, "when fd is drained");
-
-		/* Undo any unidirectional emulation. */
-		if (bidirectional)
-			Assert(drain_pipe(wfd, bidi_pipe_size));
-
-		/* Listen on the write side. An empty buffer should be writable. */
-		Assert(register_socket(NULL, rfd, CURL_POLL_REMOVE, actx, NULL) == 0);
-		Assert(register_socket(NULL, wfd, out_event, actx, NULL) == 0);
-		mux_is_ready(actx->mux, deadline, "when fd is writable");
-
-		/* As above, wait on read events instead. */
-		Assert(register_socket(NULL, wfd, CURL_POLL_IN, actx, NULL) == 0);
-		mux_is_not_ready(actx->mux, "when waiting for reads on writable fd");
-
-		/* Re-register for write events. */
-		Assert(register_socket(NULL, wfd, out_event, actx, NULL) == 0);
-		mux_is_ready(actx->mux, deadline, "when waiting for writes again");
-
-		{
-			ssize_t		written;
-
-			/*
-			 * Fill the pipe. Once the old writable event is cleared, the mux
-			 * should not be ready.
-			 */
-			Assert((written = fill_pipe(wfd)) > 0);
-			printf("# pipe buffer is full at %zd bytes\n", written);
-
-			Assert(comb_multiplexer(actx));
-			mux_is_not_ready(actx->mux, "when fd buffer is full");
-
-			/* Drain the pipe again. */
-			Assert(drain_pipe(rfd, written));
-			mux_is_ready(actx->mux, deadline, "when fd buffer is drained");
-		}
-
-		/* Stop listening. */
-		Assert(register_socket(NULL, wfd, CURL_POLL_REMOVE, actx, NULL) == 0);
-		mux_is_not_ready(actx->mux, "when fd is removed");
-
-		/* Make sure an expired timer doesn't interfere with event draining. */
-		{
-			bool		expired;
-
-			/* Make the rfd appear unidirectional if necessary. */
-			if (bidirectional)
-				Assert((bidi_pipe_size = fill_pipe(rfd)) > 0);
-
-			/* Set the timer and wait for it to expire. */
-			Assert(set_timer(actx, 0));
-			Assert(PQsocketPoll(actx->timerfd, 1, 0, deadline) > 0);
-			is(timer_expired(actx), 1, "timer is expired");
-
-			/* Register for read events and make the fd readable. */
-			Assert(register_socket(NULL, rfd, in_event, actx, NULL) == 0);
-			Assert(write(wfd, "x", 1) == 1);
-			mux_is_ready(actx->mux, deadline, "when fd is readable and timer expired");
-
-			/*
-			 * Draining the pipe should unset the multiplexer again, once the
-			 * old event is drained and the timer is reset.
-			 *
-			 * Order matters, since comb_multiplexer() doesn't have to remove
-			 * stale events when active events exist. Follow the call sequence
-			 * used in the code: drain the timer expiration, drain the pipe,
-			 * then clear the stale events.
-			 */
-			Assert(drain_timer_events(actx, &expired));
-			Assert(drain_pipe(rfd, 1));
-			Assert(comb_multiplexer(actx));
-
-			is(expired, 1, "drain_timer_events() reports expiration");
-			is(timer_expired(actx), 0, "timer is no longer expired");
-			mux_is_not_ready(actx->mux, "when fd is drained and timer reset");
-
-			/* Stop listening. */
-			Assert(register_socket(NULL, rfd, CURL_POLL_REMOVE, actx, NULL) == 0);
-
-			/* Undo any unidirectional emulation. */
-			if (bidirectional)
-				Assert(drain_pipe(wfd, bidi_pipe_size));
-		}
-
-		/* Ensure comb_multiplexer() can handle multiple stale events. */
-		{
-			int			rfd2,
-						wfd2;
-
-			/* Create a second local pipe. */
-			Assert(pipe(pipefd) == 0);
-			rfd2 = pipefd[0];
-			wfd2 = pipefd[1];
-
-			/* Make both rfds appear unidirectional if necessary. */
-			if (bidirectional)
-			{
-				Assert((bidi_pipe_size = fill_pipe(rfd)) > 0);
-				Assert(fill_pipe(rfd2) == bidi_pipe_size);
-			}
-
-			/* Register for read events on both fds, and make them readable. */
-			Assert(register_socket(NULL, rfd, in_event, actx, NULL) == 0);
-			Assert(register_socket(NULL, rfd2, in_event, actx, NULL) == 0);
-
-			Assert(write(wfd, "x", 1) == 1);
-			Assert(write(wfd2, "x", 1) == 1);
-
-			mux_is_ready(actx->mux, deadline, "when two fds are readable");
-
-			/*
-			 * Drain both fds. comb_multiplexer() should then ensure that the
-			 * mux is no longer readable.
-			 */
-			Assert(drain_pipe(rfd, 1));
-			Assert(drain_pipe(rfd2, 1));
-			Assert(comb_multiplexer(actx));
-			mux_is_not_ready(actx->mux, "when two fds are drained");
-
-			/* Stop listening. */
-			Assert(register_socket(NULL, rfd, CURL_POLL_REMOVE, actx, NULL) == 0);
-			Assert(register_socket(NULL, rfd2, CURL_POLL_REMOVE, actx, NULL) == 0);
-
-			/* Undo any unidirectional emulation. */
-			if (bidirectional)
-			{
-				Assert(drain_pipe(wfd, bidi_pipe_size));
-				Assert(drain_pipe(wfd2, bidi_pipe_size));
-			}
-
-			close(rfd2);
-			close(wfd2);
-		}
-	}
-
-	close(rfd);
-	close(wfd);
-	free_test_actx(actx);
-}
-
-int
-main(int argc, char *argv[])
-{
-	const char *timeout;
-
-	/* Grab the default timeout. */
-	timeout = getenv("PG_TEST_TIMEOUT_DEFAULT");
-	if (timeout)
-	{
-		int			timeout_s = atoi(timeout);
-
-		if (timeout_s > 0)
-			timeout_us = timeout_s * 1000 * 1000;
-	}
-
-	/*
-	 * Set up line buffering for our output, to let stderr interleave in the
-	 * log files.
-	 */
-	setvbuf(stdout, NULL, PG_IOLBF, 0);
-
-	test_set_timer();
-	test_register_socket();
-
-	printf("1..%d\n", num_tests);
-	return 0;
-}
-
-#else							/* !USE_ASSERT_CHECKING */
-
-/*
- * Skip the test suite when we don't have assertions.
- */
-int
-main(int argc, char *argv[])
-{
-	printf("1..0 # skip: cassert is not enabled\n");
-
-	return 0;
-}
-
-#endif							/* USE_ASSERT_CHECKING */