Refactor out NewEventFD to a test utility.

PiperOrigin-RevId: 231404512
Change-Id: I31efcc23a0c4a48ef6fbba3ca07415d79290f55c

8 files changed, 65 insertions, 102 deletions

diff --git a/test/syscalls/linux/BUILD b/test/syscalls/linux/BUILD
index 19884d55e..8cf83b311 100644
--- a/test/syscalls/linux/BUILD
+++ b/test/syscalls/linux/BUILD
@@ -481,6 +481,7 @@ cc_binary(
     srcs = ["dup.cc"],
     linkstatic = 1,
     deps = [
+        "//test/util:eventfd_util",
         "//test/util:file_descriptor",
         "//test/util:posix_error",
         "//test/util:temp_path",
@@ -497,6 +498,7 @@ cc_binary(
     linkstatic = 1,
     deps = [
         "//test/util:epoll_util",
+        "//test/util:eventfd_util",
         "//test/util:file_descriptor",
         "//test/util:posix_error",
         "//test/util:test_main",
@@ -511,6 +513,8 @@ cc_binary(
     srcs = ["eventfd.cc"],
     linkstatic = 1,
     deps = [
+        "//test/util:epoll_util",
+        "//test/util:eventfd_util",
         "//test/util:test_main",
         "//test/util:test_util",
         "//test/util:thread_util",
@@ -686,6 +690,7 @@ cc_binary(
     deps = [
         ":socket_test_util",
         "//test/util:cleanup",
+        "//test/util:eventfd_util",
         "//test/util:multiprocess_util",
         "//test/util:posix_error",
         "//test/util:temp_path",
@@ -817,6 +822,7 @@ cc_binary(
     srcs = ["getdents.cc"],
     linkstatic = 1,
     deps = [
+        "//test/util:eventfd_util",
         "//test/util:file_descriptor",
         "//test/util:fs_util",
         "//test/util:posix_error",
diff --git a/test/syscalls/linux/chmod.cc b/test/syscalls/linux/chmod.cc
index b7fc17946..2f2ff3b7d 100644
--- a/test/syscalls/linux/chmod.cc
+++ b/test/syscalls/linux/chmod.cc
@@ -13,7 +13,6 @@
 // limitations under the License.
 
 #include <fcntl.h>
-#include <sys/eventfd.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
diff --git a/test/syscalls/linux/dup.cc b/test/syscalls/linux/dup.cc
index fc11844fb..e8de2f4c4 100644
--- a/test/syscalls/linux/dup.cc
+++ b/test/syscalls/linux/dup.cc
@@ -13,10 +13,10 @@
 // limitations under the License.
 
 #include <fcntl.h>
-#include <sys/eventfd.h>
 #include <unistd.h>
 
 #include "gtest/gtest.h"
+#include "test/util/eventfd_util.h"
 #include "test/util/file_descriptor.h"
 #include "test/util/posix_error.h"
 #include "test/util/temp_path.h"
@@ -63,20 +63,14 @@ TEST(DupTest, Dup) {
 }
 
 TEST(DupTest, DupClearsCloExec) {
-  FileDescriptor nfd;
-
   // Open an eventfd file descriptor with FD_CLOEXEC descriptor flag set.
-  int event_fd = 0;
-  ASSERT_THAT(event_fd = eventfd(0, EFD_CLOEXEC), SyscallSucceeds());
-  FileDescriptor event_fd_closer(event_fd);
-
-  EXPECT_THAT(fcntl(event_fd_closer.get(), F_GETFD),
-              SyscallSucceedsWithValue(FD_CLOEXEC));
+  FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(NewEventFD(0, EFD_CLOEXEC));
+  EXPECT_THAT(fcntl(fd.get(), F_GETFD), SyscallSucceedsWithValue(FD_CLOEXEC));
 
   // Duplicate the descriptor. Ensure that it doesn't have FD_CLOEXEC set.
-  nfd = ASSERT_NO_ERRNO_AND_VALUE(event_fd_closer.Dup());
-  ASSERT_NE(event_fd_closer.get(), nfd.get());
-  CheckSameFile(event_fd_closer, nfd);
+  FileDescriptor nfd = ASSERT_NO_ERRNO_AND_VALUE(fd.Dup());
+  ASSERT_NE(fd.get(), nfd.get());
+  CheckSameFile(fd, nfd);
   EXPECT_THAT(fcntl(nfd.get(), F_GETFD), SyscallSucceedsWithValue(0));
 }
 
diff --git a/test/syscalls/linux/epoll.cc b/test/syscalls/linux/epoll.cc
index 46fba7b2d..7b1d83ad8 100644
--- a/test/syscalls/linux/epoll.cc
+++ b/test/syscalls/linux/epoll.cc
@@ -26,6 +26,7 @@
 
 #include "gtest/gtest.h"
 #include "test/util/epoll_util.h"
+#include "test/util/eventfd_util.h"
 #include "test/util/file_descriptor.h"
 #include "test/util/posix_error.h"
 #include "test/util/test_util.h"
@@ -38,16 +39,6 @@ namespace {
 constexpr int kFDsPerEpoll = 3;
 constexpr uint64_t kMagicConstant = 0x0102030405060708;
 
-// Returns a new eventfd.
-PosixErrorOr<FileDescriptor> NewEventFD() {
-  int fd = eventfd(/* initval = */ 0, /* flags = */ 0);
-  MaybeSave();
-  if (fd < 0) {
-    return PosixError(errno, "eventfd");
-  }
-  return FileDescriptor(fd);
-}
-
 uint64_t ms_elapsed(const struct timespec* begin, const struct timespec* end) {
   return (end->tv_sec - begin->tv_sec) * 1000 +
          (end->tv_nsec - begin->tv_nsec) / 1000000;
diff --git a/test/syscalls/linux/eventfd.cc b/test/syscalls/linux/eventfd.cc
index ffcd20622..8111da30e 100644
--- a/test/syscalls/linux/eventfd.cc
+++ b/test/syscalls/linux/eventfd.cc
@@ -18,12 +18,13 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/epoll.h>
-#include <sys/eventfd.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <unistd.h>
 
 #include "gtest/gtest.h"
+#include "test/util/epoll_util.h"
+#include "test/util/eventfd_util.h"
 #include "test/util/test_util.h"
 #include "test/util/thread_util.h"
 
@@ -33,21 +34,20 @@ namespace testing {
 namespace {
 
 TEST(EventfdTest, Nonblock) {
-  int efd;
-  ASSERT_THAT(efd = eventfd(0, EFD_NONBLOCK | EFD_SEMAPHORE),
-              SyscallSucceeds());
+  FileDescriptor efd =
+      ASSERT_NO_ERRNO_AND_VALUE(NewEventFD(0, EFD_NONBLOCK | EFD_SEMAPHORE));
 
   uint64_t l;
-  ASSERT_THAT(read(efd, &l, sizeof(l)), SyscallFailsWithErrno(EAGAIN));
+  ASSERT_THAT(read(efd.get(), &l, sizeof(l)), SyscallFailsWithErrno(EAGAIN));
 
   l = 1;
-  ASSERT_THAT(write(efd, &l, sizeof(l)), SyscallSucceeds());
+  ASSERT_THAT(write(efd.get(), &l, sizeof(l)), SyscallSucceeds());
 
   l = 0;
-  ASSERT_THAT(read(efd, &l, sizeof(l)), SyscallSucceeds());
+  ASSERT_THAT(read(efd.get(), &l, sizeof(l)), SyscallSucceeds());
   EXPECT_EQ(l, 1);
 
-  ASSERT_THAT(read(efd, &l, sizeof(l)), SyscallFailsWithErrno(EAGAIN));
+  ASSERT_THAT(read(efd.get(), &l, sizeof(l)), SyscallFailsWithErrno(EAGAIN));
 }
 
 void* read_three_times(void* arg) {
@@ -60,8 +60,8 @@ void* read_three_times(void* arg) {
 }
 
 TEST(EventfdTest, BlockingWrite) {
-  int efd;
-  ASSERT_THAT(efd = eventfd(0, EFD_SEMAPHORE), SyscallSucceeds());
+  FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(NewEventFD(0, EFD_SEMAPHORE));
+  int efd = fd.get();
 
   pthread_t p;
   ASSERT_THAT(pthread_create(&p, nullptr, read_three_times,
@@ -82,58 +82,53 @@ TEST(EventfdTest, BlockingWrite) {
 }
 
 TEST(EventfdTest, SmallWrite) {
-  int efd;
-  ASSERT_THAT(efd = eventfd(0, EFD_NONBLOCK | EFD_SEMAPHORE),
-              SyscallSucceeds());
+  FileDescriptor efd =
+      ASSERT_NO_ERRNO_AND_VALUE(NewEventFD(0, EFD_NONBLOCK | EFD_SEMAPHORE));
 
   uint64_t l = 16;
-  ASSERT_THAT(write(efd, &l, 4), SyscallFailsWithErrno(EINVAL));
+  ASSERT_THAT(write(efd.get(), &l, 4), SyscallFailsWithErrno(EINVAL));
 }
 
 TEST(EventfdTest, SmallRead) {
-  int efd;
-  ASSERT_THAT(efd = eventfd(0, EFD_NONBLOCK | EFD_SEMAPHORE),
-              SyscallSucceeds());
+  FileDescriptor efd =
+      ASSERT_NO_ERRNO_AND_VALUE(NewEventFD(0, EFD_NONBLOCK | EFD_SEMAPHORE));
 
   uint64_t l = 1;
-  ASSERT_THAT(write(efd, &l, sizeof(l)), SyscallSucceeds());
+  ASSERT_THAT(write(efd.get(), &l, sizeof(l)), SyscallSucceeds());
 
   l = 0;
-  ASSERT_THAT(read(efd, &l, 4), SyscallFailsWithErrno(EINVAL));
+  ASSERT_THAT(read(efd.get(), &l, 4), SyscallFailsWithErrno(EINVAL));
 }
 
 TEST(EventfdTest, BigWrite) {
-  int efd;
-  ASSERT_THAT(efd = eventfd(0, EFD_NONBLOCK | EFD_SEMAPHORE),
-              SyscallSucceeds());
+  FileDescriptor efd =
+      ASSERT_NO_ERRNO_AND_VALUE(NewEventFD(0, EFD_NONBLOCK | EFD_SEMAPHORE));
 
   uint64_t big[16];
   big[0] = 16;
-  ASSERT_THAT(write(efd, big, sizeof(big)), SyscallSucceeds());
+  ASSERT_THAT(write(efd.get(), big, sizeof(big)), SyscallSucceeds());
 }
 
 TEST(EventfdTest, BigRead) {
-  int efd;
-  ASSERT_THAT(efd = eventfd(0, EFD_NONBLOCK | EFD_SEMAPHORE),
-              SyscallSucceeds());
+  FileDescriptor efd =
+      ASSERT_NO_ERRNO_AND_VALUE(NewEventFD(0, EFD_NONBLOCK | EFD_SEMAPHORE));
 
   uint64_t l = 1;
-  ASSERT_THAT(write(efd, &l, sizeof(l)), SyscallSucceeds());
+  ASSERT_THAT(write(efd.get(), &l, sizeof(l)), SyscallSucceeds());
 
   uint64_t big[16];
-  ASSERT_THAT(read(efd, big, sizeof(big)), SyscallSucceeds());
+  ASSERT_THAT(read(efd.get(), big, sizeof(big)), SyscallSucceeds());
   EXPECT_EQ(big[0], 1);
 }
 
 TEST(EventfdTest, BigWriteBigRead) {
-  int efd;
-  ASSERT_THAT(efd = eventfd(0, EFD_NONBLOCK | EFD_SEMAPHORE),
-              SyscallSucceeds());
+  FileDescriptor efd =
+      ASSERT_NO_ERRNO_AND_VALUE(NewEventFD(0, EFD_NONBLOCK | EFD_SEMAPHORE));
 
   uint64_t l[16];
   l[0] = 16;
-  ASSERT_THAT(write(efd, l, sizeof(l)), SyscallSucceeds());
-  ASSERT_THAT(read(efd, l, sizeof(l)), SyscallSucceeds());
+  ASSERT_THAT(write(efd.get(), l, sizeof(l)), SyscallSucceeds());
+  ASSERT_THAT(read(efd.get(), l, sizeof(l)), SyscallSucceeds());
   EXPECT_EQ(l[0], 1);
 }
 
@@ -142,44 +137,39 @@ TEST(EventfdTest, NotifyNonZero_NoRandomSave) {
   // Waits will time out at 10 seconds.
   constexpr int kEpollTimeoutMs = 10000;
   // Create an eventfd descriptor.
-  int efd;
-  ASSERT_THAT(efd = eventfd(7, EFD_SEMAPHORE | EFD_NONBLOCK),
-              SyscallSucceeds());
+  FileDescriptor efd =
+      ASSERT_NO_ERRNO_AND_VALUE(NewEventFD(7, EFD_NONBLOCK | EFD_SEMAPHORE));
   // Create an epoll fd to listen to efd.
-  int epollfd;
-  ASSERT_THAT(epollfd = epoll_create1(0), SyscallSucceeds());
+  FileDescriptor epollfd = ASSERT_NO_ERRNO_AND_VALUE(NewEpollFD());
   // Add efd to epoll.
-  struct epoll_event add_ev;
-  add_ev.events = EPOLLIN | EPOLLET;
-  add_ev.data.fd = efd;
-  ASSERT_THAT(epoll_ctl(epollfd, EPOLL_CTL_ADD, efd, &add_ev),
-              SyscallSucceeds());
+  ASSERT_NO_ERRNO(
+      RegisterEpollFD(epollfd.get(), efd.get(), EPOLLIN | EPOLLET, efd.get()));
 
   // Use epoll to get a value from efd.
   struct epoll_event out_ev;
-  int wait_out = epoll_wait(epollfd, &out_ev, 1, kEpollTimeoutMs);
+  int wait_out = epoll_wait(epollfd.get(), &out_ev, 1, kEpollTimeoutMs);
   EXPECT_EQ(wait_out, 1);
-  EXPECT_EQ(efd, out_ev.data.fd);
+  EXPECT_EQ(efd.get(), out_ev.data.fd);
   uint64_t val = 0;
-  ASSERT_THAT(read(efd, &val, sizeof(val)), SyscallSucceeds());
+  ASSERT_THAT(read(efd.get(), &val, sizeof(val)), SyscallSucceeds());
   EXPECT_EQ(val, 1);
 
   // Start a thread that, after this thread blocks on epoll_wait, will write to
   // efd. This is racy -- it's possible that this write will happen after
   // epoll_wait times out.
-  ScopedThread t([efd] {
+  ScopedThread t([&efd] {
     sleep(5);
     uint64_t val = 1;
-    write(efd, &val, sizeof(val));
+    write(efd.get(), &val, sizeof(val));
   });
 
   // epoll_wait should return once the thread writes.
-  wait_out = epoll_wait(epollfd, &out_ev, 1, kEpollTimeoutMs);
+  wait_out = epoll_wait(epollfd.get(), &out_ev, 1, kEpollTimeoutMs);
   EXPECT_EQ(wait_out, 1);
-  EXPECT_EQ(efd, out_ev.data.fd);
+  EXPECT_EQ(efd.get(), out_ev.data.fd);
 
   val = 0;
-  ASSERT_THAT(read(efd, &val, sizeof(val)), SyscallSucceeds());
+  ASSERT_THAT(read(efd.get(), &val, sizeof(val)), SyscallSucceeds());
   EXPECT_EQ(val, 1);
 }
 
diff --git a/test/syscalls/linux/fallocate.cc b/test/syscalls/linux/fallocate.cc
index 53aedd4e4..e51538734 100644
--- a/test/syscalls/linux/fallocate.cc
+++ b/test/syscalls/linux/fallocate.cc
@@ -13,7 +13,6 @@
 // limitations under the License.
 
 #include <fcntl.h>
-#include <sys/eventfd.h>
 #include <unistd.h>
 
 #include "gtest/gtest.h"
diff --git a/test/syscalls/linux/fcntl.cc b/test/syscalls/linux/fcntl.cc
index 355334bfa..32a90a163 100644
--- a/test/syscalls/linux/fcntl.cc
+++ b/test/syscalls/linux/fcntl.cc
@@ -14,7 +14,6 @@
 
 #include <fcntl.h>
 #include <signal.h>
-#include <sys/eventfd.h>
 #include <syscall.h>
 #include <unistd.h>
 
@@ -27,6 +26,7 @@
 #include "absl/time/time.h"
 #include "test/syscalls/linux/socket_test_util.h"
 #include "test/util/cleanup.h"
+#include "test/util/eventfd_util.h"
 #include "test/util/multiprocess_util.h"
 #include "test/util/posix_error.h"
 #include "test/util/temp_path.h"
@@ -112,17 +112,9 @@ PosixErrorOr<Cleanup> SubprocessLock(std::string const& path, bool for_write,
   return std::move(cleanup);
 }
 
-PosixErrorOr<FileDescriptor> Eventfd(int count, int flags) {
-  int efd = eventfd(count, flags);
-  if (efd < 0) {
-    return PosixError(errno, "Eventfd");
-  }
-  return FileDescriptor(efd);
-}
-
 TEST(FcntlTest, SetCloExec) {
   // Open an eventfd file descriptor with FD_CLOEXEC descriptor flag not set.
-  FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Eventfd(0, 0));
+  FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(NewEventFD(0, 0));
   ASSERT_THAT(fcntl(fd.get(), F_GETFD), SyscallSucceedsWithValue(0));
 
   // Set the FD_CLOEXEC flag.
@@ -132,7 +124,7 @@ TEST(FcntlTest, SetCloExec) {
 
 TEST(FcntlTest, ClearCloExec) {
   // Open an eventfd file descriptor with FD_CLOEXEC descriptor flag set.
-  FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Eventfd(0, EFD_CLOEXEC));
+  FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(NewEventFD(0, EFD_CLOEXEC));
   ASSERT_THAT(fcntl(fd.get(), F_GETFD), SyscallSucceedsWithValue(FD_CLOEXEC));
 
   // Clear the FD_CLOEXEC flag.
@@ -142,7 +134,7 @@ TEST(FcntlTest, ClearCloExec) {
 
 TEST(FcntlTest, IndependentDescriptorFlags) {
   // Open an eventfd file descriptor with FD_CLOEXEC descriptor flag not set.
-  FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(Eventfd(0, 0));
+  FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(NewEventFD(0, 0));
   ASSERT_THAT(fcntl(fd.get(), F_GETFD), SyscallSucceedsWithValue(0));
 
   // Duplicate the descriptor. Ensure that it also doesn't have FD_CLOEXEC.
diff --git a/test/syscalls/linux/getdents.cc b/test/syscalls/linux/getdents.cc
index 5db580aa0..526925599 100644
--- a/test/syscalls/linux/getdents.cc
+++ b/test/syscalls/linux/getdents.cc
@@ -19,13 +19,13 @@
 #include <stdint.h>
 #include <stdio.h>
 #include <string.h>
-#include <sys/eventfd.h>
 #include <sys/mman.h>
 #include <sys/types.h>
 #include <syscall.h>
 #include <unistd.h>
 #include <map>
 #include <string>
+#include <unordered_map>
 #include <unordered_set>
 #include <utility>
 
@@ -33,6 +33,7 @@
 #include "gtest/gtest.h"
 #include "absl/strings/numbers.h"
 #include "absl/strings/str_cat.h"
+#include "test/util/eventfd_util.h"
 #include "test/util/file_descriptor.h"
 #include "test/util/fs_util.h"
 #include "test/util/posix_error.h"
@@ -368,16 +369,11 @@ TYPED_TEST(GetdentsTest, PartialBuffer) {
 // getdents iterates correctly despite mutation of /proc/self/fd.
 TYPED_TEST(GetdentsTest, ProcSelfFd) {
   constexpr size_t kNfds = 10;
-  std::unordered_set<int> fds;
-  std::vector<FileDescriptor> fd_closers;
-  fd_closers.reserve(fds.size());
-  for (int fd : fds) {
-    fd_closers.emplace_back(fd);
-  }
+  std::unordered_map<int, FileDescriptor> fds;
+  fds.reserve(kNfds);
   for (size_t i = 0; i < kNfds; i++) {
-    int fd;
-    ASSERT_THAT(fd = eventfd(0, 0), SyscallSucceeds());
-    fds.insert(fd);
+    FileDescriptor fd = ASSERT_NO_ERRNO_AND_VALUE(NewEventFD());
+    fds.emplace(fd.get(), std::move(fd));
   }
 
   const FileDescriptor proc_self_fd =
@@ -401,11 +397,7 @@ TYPED_TEST(GetdentsTest, ProcSelfFd) {
       if (!absl::SimpleAtoi(d->d_name, &dfd)) continue;
       EXPECT_TRUE(prev_fds.insert(dfd).second)
           << "Repeated observation of /proc/self/fd/" << dfd;
-      auto it = fds.find(dfd);
-      if (it != fds.end()) {
-        fds.erase(it);
-        EXPECT_THAT(close(dfd), SyscallSucceeds());
-      }
+      fds.erase(dfd);
     }
   }