Move some logic to truffleposix library.

Author: aardvark179

src/main/c/truffleposix/truffleposix.c

@@ -46,6 +46,7 @@ SUCH DAMAGE.
 #include <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
+#include <poll.h>
 #include <pwd.h>
 #include <spawn.h>
 #include <stdint.h>
@@ -110,6 +111,15 @@ static void mark_ready_from_set(fd_set *set, int nfds, int *fds) {
   }
 }
 
+int truffleposix_poll(int fd, int events, int timeout) {
+  struct pollfd fds;
+
+  fds.fd = fd;
+  fds.events = events;
+
+  return poll(&fds, 1, timeout);
+}
+
 int truffleposix_select(int nread, int *readfds, int nwrite, int *writefds,
                         int nexcept, int *exceptfds, long timeout_us) {
   struct timeval timeout;

src/main/ruby/truffleruby/core/posix.rb

@@ -215,6 +215,7 @@ def self.attach_function_eagerly(native_name, argument_types, return_type,
   attach_function :opendir, [:string], :pointer
   attach_function :pipe, [:pointer], :int
   attach_function :poll, [:pointer, :long, :int], :int, LIBC, true
+  attach_function :truffleposix_poll, [:pointer, :long, :int], :int, LIBTRUFFLEPOSIX, true
   attach_function :read, [:int, :pointer, :size_t], :ssize_t, LIBC, true
   attach_function :readlink, [:string, :pointer, :size_t], :ssize_t
   attach_function :realpath, [:string, :pointer], :pointer

src/main/ruby/truffleruby/core/truffle/io_operations.rb

@@ -222,38 +222,31 @@ def self.poll(io, events, timeout)
         remaining_timeout = -1
       end
 
-      pollfd = Primitive.io_thread_buffer_allocate(POLLFD_SIZE)
       begin
-        pollfd.put_int(POLLFD_FD_OFFSET, Primitive.io_fd(io))
-        pollfd.put_uint16(POLLFD_EVENTS_OFFSET, events)
-        begin
-          primitive_result = Truffle::POSIX.poll(pollfd, 1, remaining_timeout)
-          result =
-            if primitive_result < 0
-              errno = Errno.errno
-              if errno == Errno::EINTR::Errno
-                if timeout
-                  # Update timeout
-                  now = Process.clock_gettime(Process::CLOCK_MONOTONIC, :millisecond)
-                  if now >= deadline
-                    false # timeout
-                  else
-                    remaining_timeout = deadline - now
-                    :retry
-                  end
+        primitive_result = Truffle::POSIX.truffleposix_poll(Primitive.io_fd(io), events, remaining_timeout)
+        result =
+          if primitive_result < 0
+            errno = Errno.errno
+            if errno == Errno::EINTR::Errno
+              if timeout
+                # Update timeout
+                now = Process.clock_gettime(Process::CLOCK_MONOTONIC, :millisecond)
+                if now >= deadline
+                  false # timeout
                 else
+                  remaining_timeout = deadline - now
                   :retry
                 end
               else
-                Errno.handle_errno(errno)
+                :retry
               end
             else
-              primitive_result > 0
+              Errno.handle_errno(errno)
             end
-        end while result == :retry
-      ensure
-        Primitive.io_thread_buffer_free(pollfd)
-      end
+          else
+            primitive_result > 0
+          end
+      end while result == :retry
 
       result
     end