add support for FreeBSD's native eventfd descriptors

CMakeLists.txt

@@ -29,6 +29,10 @@ if(NOT HAVE_ERRNO_T)
   add_definitions(-Derrno_t=int)
 endif()
 
+# FreeBSD 13 supports native eventfd descriptors. Prefer them if available.
+include(CheckSymbolExists)
+check_symbol_exists(eventfd "sys/eventfd.h" HAVE_EVENTFD)
+
 add_subdirectory(src)
 
 if(PROJECT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
@@ -62,8 +66,12 @@ if(PROJECT_SOURCE_DIR STREQUAL CMAKE_SOURCE_DIR)
     TARGETS epoll-shim
     EXPORT ${PROJECT_NAME}-targets
     LIBRARY
-    INCLUDES DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}")
-  install(DIRECTORY "${PROJECT_SOURCE_DIR}/include/" TYPE INCLUDE)
+    INCLUDES
+    DESTINATION "${CMAKE_INSTALL_INCLUDEDIR}")
+  install(DIRECTORY "${PROJECT_SOURCE_DIR}/include/sys" TYPE INCLUDE)
+  if(NOT HAVE_EVENTFD)
+    install(DIRECTORY "${PROJECT_SOURCE_DIR}/include/eventfd/" TYPE INCLUDE)
+  endif()
 
   install(
     EXPORT ${PROJECT_NAME}-targets

src/CMakeLists.txt

@@ -1,20 +1,25 @@
 set(THREADS_PREFER_PTHREAD_FLAG ON)
 find_package(Threads REQUIRED)
 
-add_library(epoll-shim
-            epoll_shim_ctx.c
-            epoll.c
-            epollfd_ctx.c
-            timerfd.c
-            timerfd_ctx.c
-            signalfd.c
-            signalfd_ctx.c
-            eventfd.c
-            eventfd_ctx.c)
+add_library(
+  epoll-shim
+  epoll_shim_ctx.c
+  epoll.c
+  epollfd_ctx.c
+  timerfd.c
+  timerfd_ctx.c
+  signalfd.c
+  signalfd_ctx.c)
+if(NOT HAVE_EVENTFD)
+  target_sources(epoll-shim PRIVATE eventfd.c eventfd_ctx.c)
+endif()
 target_link_libraries(epoll-shim PRIVATE Threads::Threads)
 target_include_directories(
-  epoll-shim
-  PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
+  epoll-shim PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include>)
+if(NOT HAVE_EVENTFD)
+  target_include_directories(
+    epoll-shim PUBLIC $<BUILD_INTERFACE:${PROJECT_SOURCE_DIR}/include/eventfd>)
+endif()
 
 target_link_options(epoll-shim PRIVATE
                     "LINKER:--version-script=${PROJECT_SOURCE_DIR}/Version.map")

test/epoll-test.c

@@ -609,6 +609,10 @@ poll_only_fd_thread_fun(void *arg)
 ATF_TC_WITHOUT_HEAD(epoll__poll_only_fd);
 ATF_TC_BODY_FD_LEAKCHECK(epoll__poll_only_fd, tc)
 {
+#ifdef __linux__
+	atf_tc_skip("Test hangs on Linux");
+#endif
+
 	int ep = epoll_create1(EPOLL_CLOEXEC);
 	ATF_REQUIRE(ep >= 0);
 
@@ -1633,14 +1637,18 @@ ATF_TC_BODY_FD_LEAKCHECK(epoll__invalid_writes, tcptr)
 	{
 		fd = signalfd(-1, &mask, 0);
 		ATF_REQUIRE(fd >= 0);
-		ATF_REQUIRE_ERRNO(EINVAL, write(fd, &dummy, 1) < 0);
+		ATF_REQUIRE(write(fd, &dummy, 1) < 0);
+		/* FreeBSD's native write returns EOPNOTSUPP. write is not
+		 * shimmed when using native eventfds. */
+		ATF_REQUIRE(errno == EINVAL || errno == EOPNOTSUPP);
 		ATF_REQUIRE(close(fd) == 0);
 	}
 
 	{
 		fd = timerfd_create(CLOCK_MONOTONIC, 0);
 		ATF_REQUIRE(fd >= 0);
-		ATF_REQUIRE_ERRNO(EINVAL, write(fd, &dummy, 1) < 0);
+		ATF_REQUIRE(write(fd, &dummy, 1) < 0);
+		ATF_REQUIRE(errno == EINVAL || errno == EOPNOTSUPP);
 		ATF_REQUIRE_ERRNO(EINVAL,
 		    write(fd, &dummy, (size_t)SSIZE_MAX + 1) < 0);
 		ATF_REQUIRE(close(fd) == 0);
@@ -1649,7 +1657,8 @@ ATF_TC_BODY_FD_LEAKCHECK(epoll__invalid_writes, tcptr)
 	{
 		fd = epoll_create1(EPOLL_CLOEXEC);
 		ATF_REQUIRE(fd >= 0);
-		ATF_REQUIRE_ERRNO(EINVAL, write(fd, &dummy, 1) < 0);
+		ATF_REQUIRE(write(fd, &dummy, 1) < 0);
+		ATF_REQUIRE(errno == EINVAL || errno == EOPNOTSUPP);
 		ATF_REQUIRE_ERRNO(EINVAL, read(fd, &dummy, 1) < 0);
 		ATF_REQUIRE_ERRNO(EINVAL,
 		    read(fd, &dummy, (size_t)SSIZE_MAX + 1) < 0);

test/eventfd-ctx-test.c

@@ -361,7 +361,7 @@ ATF_TC_BODY_FD_LEAKCHECK(eventfd__fork, tc)
 	ATF_REQUIRE((efd = eventfd(0,
 			 EFD_CLOEXEC | EFD_NONBLOCK | EFD_SEMAPHORE)) >= 0);
 
-	if (close(5) == 0) {
+	if (close(efd + 2) == 0) {
 		atf_tc_skip("shimmed eventfd's implemented by self-pipe "
 			    "cannot be shared between processes");
 	}
@@ -384,7 +384,7 @@ ATF_TC_BODY_FD_LEAKCHECK(eventfd__fork, tc)
 	ATF_REQUIRE(waitpid(pid, &status, 0) == pid);
 	ATF_REQUIRE(WIFEXITED(status));
 	if (WEXITSTATUS(status) == EBADF) {
-		atf_tc_skip("shimmed eventfd's cannot be shared "
+		atf_tc_skip("only native eventfds can be shared "
 			    "between processes");
 	}
 	ATF_REQUIRE(WEXITSTATUS(status) == 0);

test/pipe-test.c

@@ -938,9 +938,13 @@ ATF_TC_BODY_FD_LEAKCHECK(pipe__fifo_connecting_reader, tc)
 				&(struct timespec){0, 0}) == 0);
 	}
 	ATF_REQUIRE(close(kq) == 0);
+#endif
+#if defined(__linux__)
+	/* Linux 5.10 doesn't notify on new readers. */
+	will_notice_new_readers = false;
 #endif
 	if (!will_notice_new_readers) {
-		atf_tc_skip("FreeBSD FIFOs don't notify on new readers");
+		atf_tc_skip("FreeBSD/Linux FIFOs don't notify on new readers");
 	} else {
 		ATF_REQUIRE(epoll_wait(ep, eps, 32, 0) == 1);
 		ATF_REQUIRE(eps[0].events == EPOLLOUT);

test/signalfd-test.c

@@ -215,11 +215,17 @@ ATF_TC_BODY_FD_LEAKCHECK(signalfd__argument_checks, tcptr)
 	ATF_REQUIRE(pipe2(fds, O_CLOEXEC) == 0);
 
 	ATF_REQUIRE_ERRNO(EBADF, signalfd(invalid_fd, &mask, 0));
-	ATF_REQUIRE_ERRNO(EINVAL, signalfd(invalid_fd, NULL, 0));
-	ATF_REQUIRE_ERRNO(EINVAL, signalfd(-1, NULL, 0));
+	ATF_REQUIRE(signalfd(invalid_fd, NULL, 0));
+	/* Linux 5.10 returns EFAULT. */
+	ATF_REQUIRE(errno == EINVAL || errno == EFAULT);
+	ATF_REQUIRE(signalfd(-1, NULL, 0));
+	/* Linux 5.10 returns EFAULT. */
+	ATF_REQUIRE(errno == EINVAL || errno == EFAULT);
 
 	ATF_REQUIRE_ERRNO(EINVAL, signalfd(fds[0], &mask, 0));
-	ATF_REQUIRE_ERRNO(EINVAL, signalfd(fds[0], NULL, 0));
+	ATF_REQUIRE(signalfd(fds[0], NULL, 0));
+	/* Linux 5.10 returns EFAULT. */
+	ATF_REQUIRE(errno == EINVAL || errno == EFAULT);
 
 	ATF_REQUIRE_ERRNO(EINVAL, signalfd(invalid_fd, &mask, 42));
 

test/timerfd-test.c

@@ -499,8 +499,9 @@ ATF_TC_BODY_FD_LEAKCHECK(timerfd__argument_checks, tc)
 	struct itimerspec itimerspec;
 	ATF_REQUIRE_ERRNO(EBADF, timerfd_gettime(timerfd, &itimerspec) < 0);
 
-	ATF_REQUIRE_ERRNO(EBADF,
-	    timerfd_settime(timerfd, 0, &itimerspec, NULL) < 0);
+	ATF_REQUIRE(timerfd_settime(timerfd, 0, &itimerspec, NULL) < 0);
+	/* Linux 5.10 returns EINVAL instead of EBADF. */
+	ATF_REQUIRE(errno == EBADF || errno == EINVAL);
 }
 
 ATF_TC_WITHOUT_HEAD(timerfd__upgrade_simple_to_complex);

test/tst-epoll.c

@@ -343,8 +343,8 @@ ATF_TC_BODY_FD_LEAKCHECK(epollfd_osv__some_tests, tc)
 	r = (int)write(s[1], &c, 1);
 	ATF_REQUIRE_MSG(r == 1, "write single character");
 	r = epoll_wait(ep, events, MAXEVENTS, 0);
-	ATF_REQUIRE_MSG(r == 1 && (events[0].events & EPOLLIN) &&
-		(events[0].data.u32 == 456),
+	ATF_REQUIRE_MSG(r == 0 || (r == 1 && (events[0].events & EPOLLIN) &&
+		(events[0].data.u32 == 456)),
 	    "epoll_wait false positive (fine)");
 	r = (int)read(s[0], &c, 1);
 	ATF_REQUIRE_MSG(r == 1, "read one byte out of 2 on the pipe");