[dart:io] Always use O_CLOEXEC instead of FD_CLOEXEC on Linux.

TEST=ci
Bug: #60252
Change-Id: Ide6d156d8a7c569984d4fa702dc32ac08f9ee9e1
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/426580
Reviewed-by: Brian Quinlan <[email protected]>
Reviewed-by: Siva Annamalai <[email protected]>
Commit-Queue: Ryan Macnak <[email protected]>

Author: rmacnak-google

runtime/bin/eventhandler_linux.cc

@@ -73,30 +73,20 @@ static void AddToEpollInstance(intptr_t epoll_fd_, DescriptorInfo* di) {
 EventHandlerImplementation::EventHandlerImplementation()
     : socket_map_(&SimpleHashMap::SamePointerValue, 16) {
   intptr_t result;
-  result = NO_RETRY_EXPECTED(pipe(interrupt_fds_));
+  result = NO_RETRY_EXPECTED(pipe2(interrupt_fds_, O_CLOEXEC));
   if (result != 0) {
     FATAL("Pipe creation failed");
   }
   if (!FDUtils::SetNonBlocking(interrupt_fds_[0])) {
     FATAL("Failed to set pipe fd non blocking\n");
   }
-  if (!FDUtils::SetCloseOnExec(interrupt_fds_[0])) {
-    FATAL("Failed to set pipe fd close on exec\n");
-  }
-  if (!FDUtils::SetCloseOnExec(interrupt_fds_[1])) {
-    FATAL("Failed to set pipe fd close on exec\n");
-  }
   shutdown_ = false;
   // The initial size passed to epoll_create is ignore on newer (>=
   // 2.6.8) Linux versions
-  const int kEpollInitialSize = 64;
-  epoll_fd_ = NO_RETRY_EXPECTED(epoll_create(kEpollInitialSize));
+  epoll_fd_ = NO_RETRY_EXPECTED(epoll_create1(O_CLOEXEC));
   if (epoll_fd_ == -1) {
     FATAL("Failed creating epoll file descriptor: %i", errno);
   }
-  if (!FDUtils::SetCloseOnExec(epoll_fd_)) {
-    FATAL("Failed to set epoll fd close on exec\n");
-  }
   // Register the interrupt_fd with the epoll instance.
   struct epoll_event event;
   event.events = EPOLLIN;

runtime/bin/fdutils_linux.cc

@@ -18,18 +18,8 @@ namespace dart {
 namespace bin {
 
 bool FDUtils::SetCloseOnExec(intptr_t fd) {
-  intptr_t status;
-  status = NO_RETRY_EXPECTED(fcntl(fd, F_GETFD));
-  if (status < 0) {
-    perror("fcntl(F_GETFD) failed");
-    return false;
-  }
-  status |= FD_CLOEXEC;
-  if (NO_RETRY_EXPECTED(fcntl(fd, F_SETFD, status)) < 0) {
-    perror("fcntl(F_SETFD, FD_CLOEXEC) failed");
-    return false;
-  }
-  return true;
+  FATAL("Use O_CLOEXEC instead");
+  return false;
 }
 
 static bool SetBlockingHelper(intptr_t fd, bool blocking) {

runtime/bin/socket_linux.cc

@@ -252,7 +252,8 @@ intptr_t ServerSocket::Accept(intptr_t fd) {
   intptr_t socket;
   struct sockaddr clientaddr;
   socklen_t addrlen = sizeof(clientaddr);
-  socket = TEMP_FAILURE_RETRY(accept(fd, &clientaddr, &addrlen));
+  socket = TEMP_FAILURE_RETRY(
+      accept4(fd, &clientaddr, &addrlen, SOCK_NONBLOCK | SOCK_CLOEXEC));
   if (socket == -1) {
     if (IsTemporaryAcceptError(errno)) {
       // We need to signal to the caller that this is actually not an
@@ -261,15 +262,6 @@ intptr_t ServerSocket::Accept(intptr_t fd) {
       ASSERT(kTemporaryFailure != -1);
       socket = kTemporaryFailure;
     }
-  } else {
-    if (!FDUtils::SetCloseOnExec(socket)) {
-      FDUtils::SaveErrorAndClose(socket);
-      return -1;
-    }
-    if (!FDUtils::SetNonBlocking(socket)) {
-      FDUtils::SaveErrorAndClose(socket);
-      return -1;
-    }
   }
   return socket;
 }