Allow #fsync and #flock_* on IO::FileDescriptor (#14432)

src/crystal/system/unix/file.cr

@@ -218,58 +218,4 @@ module Crystal::System::File
       raise ::File::Error.from_errno("Error truncating file", file: path)
     end
   end
-
-  private def system_flock_shared(blocking)
-    flock LibC::FlockOp::SH, blocking
-  end
-
-  private def system_flock_exclusive(blocking)
-    flock LibC::FlockOp::EX, blocking
-  end
-
-  private def system_flock_unlock
-    flock LibC::FlockOp::UN
-  end
-
-  private def flock(op : LibC::FlockOp, retry : Bool) : Nil
-    op |= LibC::FlockOp::NB
-
-    if retry
-      until flock(op)
-        sleep 0.1
-      end
-    else
-      flock(op) || raise IO::Error.from_errno("Error applying file lock: file is already locked", target: self)
-    end
-  end
-
-  private def flock(op) : Bool
-    if 0 == LibC.flock(fd, op)
-      true
-    else
-      errno = Errno.value
-      if errno.in?(Errno::EAGAIN, Errno::EWOULDBLOCK)
-        false
-      else
-        raise IO::Error.from_os_error("Error applying or removing file lock", errno, target: self)
-      end
-    end
-  end
-
-  private def system_fsync(flush_metadata = true) : Nil
-    ret =
-      if flush_metadata
-        LibC.fsync(fd)
-      else
-        {% if flag?(:dragonfly) %}
-          LibC.fsync(fd)
-        {% else %}
-          LibC.fdatasync(fd)
-        {% end %}
-      end
-
-    if ret != 0
-      raise IO::Error.from_errno("Error syncing file", target: self)
-    end
-  end
 end

src/crystal/system/unix/file_descriptor.cr

@@ -154,6 +154,60 @@ module Crystal::System::FileDescriptor
     end
   end
 
+  private def system_flock_shared(blocking)
+    flock LibC::FlockOp::SH, blocking
+  end
+
+  private def system_flock_exclusive(blocking)
+    flock LibC::FlockOp::EX, blocking
+  end
+
+  private def system_flock_unlock
+    flock LibC::FlockOp::UN
+  end
+
+  private def flock(op : LibC::FlockOp, retry : Bool) : Nil
+    op |= LibC::FlockOp::NB
+
+    if retry
+      until flock(op)
+        sleep 0.1
+      end
+    else
+      flock(op) || raise IO::Error.from_errno("Error applying file lock: file is already locked", target: self)
+    end
+  end
+
+  private def flock(op) : Bool
+    if 0 == LibC.flock(fd, op)
+      true
+    else
+      errno = Errno.value
+      if errno.in?(Errno::EAGAIN, Errno::EWOULDBLOCK)
+        false
+      else
+        raise IO::Error.from_os_error("Error applying or removing file lock", errno, target: self)
+      end
+    end
+  end
+
+  private def system_fsync(flush_metadata = true) : Nil
+    ret =
+      if flush_metadata
+        LibC.fsync(fd)
+      else
+        {% if flag?(:dragonfly) %}
+          LibC.fsync(fd)
+        {% else %}
+          LibC.fdatasync(fd)
+        {% end %}
+      end
+
+    if ret != 0
+      raise IO::Error.from_errno("Error syncing file", target: self)
+    end
+  end
+
   def self.pipe(read_blocking, write_blocking)
     pipe_fds = uninitialized StaticArray(LibC::Int, 2)
     if LibC.pipe(pipe_fds) != 0

src/crystal/system/wasi/file.cr

@@ -18,22 +18,6 @@ module Crystal::System::File
     raise NotImplementedError.new "Crystal::System::File.utime"
   end
 
-  private def system_flock_shared(blocking)
-    raise NotImplementedError.new "Crystal::System::File#system_flock_shared"
-  end
-
-  private def system_flock_exclusive(blocking)
-    raise NotImplementedError.new "Crystal::System::File#system_flock_exclusive"
-  end
-
-  private def system_flock_unlock
-    raise NotImplementedError.new "Crystal::System::File#system_flock_unlock"
-  end
-
-  private def flock(op : LibC::FlockOp, blocking : Bool = true)
-    raise NotImplementedError.new "Crystal::System::File#flock"
-  end
-
   def self.delete(path : String, *, raise_on_missing : Bool) : Bool
     raise NotImplementedError.new "Crystal::System::File.delete"
   end

src/crystal/system/wasi/file_descriptor.cr

@@ -24,6 +24,22 @@ module Crystal::System::FileDescriptor
     raise NotImplementedError.new "Crystal::System::FileDescriptor#system_reopen"
   end
 
+  private def system_flock_shared(blocking)
+    raise NotImplementedError.new "Crystal::System::File#system_flock_shared"
+  end
+
+  private def system_flock_exclusive(blocking)
+    raise NotImplementedError.new "Crystal::System::File#system_flock_exclusive"
+  end
+
+  private def system_flock_unlock
+    raise NotImplementedError.new "Crystal::System::File#system_flock_unlock"
+  end
+
+  private def flock(op : LibC::FlockOp, blocking : Bool = true)
+    raise NotImplementedError.new "Crystal::System::File#flock"
+  end
+
   private def system_echo(enable : Bool, & : ->)
     raise NotImplementedError.new "Crystal::System::FileDescriptor#system_echo"
   end

src/crystal/system/win32/file.cr

@@ -461,61 +461,4 @@ module Crystal::System::File
       LibC.SetFilePointerEx(handle, old_pos, nil, IO::Seek::Set)
     end
   end
-
-  private def system_flock_shared(blocking : Bool) : Nil
-    flock(false, blocking)
-  end
-
-  private def system_flock_exclusive(blocking : Bool) : Nil
-    flock(true, blocking)
-  end
-
-  private def system_flock_unlock : Nil
-    unlock_file(windows_handle)
-  end
-
-  private def flock(exclusive, retry)
-    flags = LibC::LOCKFILE_FAIL_IMMEDIATELY
-    flags |= LibC::LOCKFILE_EXCLUSIVE_LOCK if exclusive
-
-    handle = windows_handle
-    if retry
-      until lock_file(handle, flags)
-        sleep 0.1
-      end
-    else
-      lock_file(handle, flags) || raise IO::Error.from_winerror("Error applying file lock: file is already locked")
-    end
-  end
-
-  private def lock_file(handle, flags)
-    # lpOverlapped must be provided despite the synchronous use of this method.
-    overlapped = LibC::OVERLAPPED.new
-    # lock the entire file with offset 0 in overlapped and number of bytes set to max value
-    if 0 != LibC.LockFileEx(handle, flags, 0, 0xFFFF_FFFF, 0xFFFF_FFFF, pointerof(overlapped))
-      true
-    else
-      winerror = WinError.value
-      if winerror == WinError::ERROR_LOCK_VIOLATION
-        false
-      else
-        raise IO::Error.from_os_error("LockFileEx", winerror, target: self)
-      end
-    end
-  end
-
-  private def unlock_file(handle)
-    # lpOverlapped must be provided despite the synchronous use of this method.
-    overlapped = LibC::OVERLAPPED.new
-    # unlock the entire file with offset 0 in overlapped and number of bytes set to max value
-    if 0 == LibC.UnlockFileEx(handle, 0, 0xFFFF_FFFF, 0xFFFF_FFFF, pointerof(overlapped))
-      raise IO::Error.from_winerror("UnLockFileEx")
-    end
-  end
-
-  private def system_fsync(flush_metadata = true) : Nil
-    if LibC.FlushFileBuffers(windows_handle) == 0
-      raise IO::Error.from_winerror("Error syncing file", target: self)
-    end
-  end
 end

src/crystal/system/win32/file_descriptor.cr

@@ -178,6 +178,63 @@ module Crystal::System::FileDescriptor
     end
   end
 
+  private def system_flock_shared(blocking : Bool) : Nil
+    flock(false, blocking)
+  end
+
+  private def system_flock_exclusive(blocking : Bool) : Nil
+    flock(true, blocking)
+  end
+
+  private def system_flock_unlock : Nil
+    unlock_file(windows_handle)
+  end
+
+  private def flock(exclusive, retry)
+    flags = LibC::LOCKFILE_FAIL_IMMEDIATELY
+    flags |= LibC::LOCKFILE_EXCLUSIVE_LOCK if exclusive
+
+    handle = windows_handle
+    if retry
+      until lock_file(handle, flags)
+        sleep 0.1
+      end
+    else
+      lock_file(handle, flags) || raise IO::Error.from_winerror("Error applying file lock: file is already locked")
+    end
+  end
+
+  private def lock_file(handle, flags)
+    # lpOverlapped must be provided despite the synchronous use of this method.
+    overlapped = LibC::OVERLAPPED.new
+    # lock the entire file with offset 0 in overlapped and number of bytes set to max value
+    if 0 != LibC.LockFileEx(handle, flags, 0, 0xFFFF_FFFF, 0xFFFF_FFFF, pointerof(overlapped))
+      true
+    else
+      winerror = WinError.value
+      if winerror == WinError::ERROR_LOCK_VIOLATION
+        false
+      else
+        raise IO::Error.from_os_error("LockFileEx", winerror, target: self)
+      end
+    end
+  end
+
+  private def unlock_file(handle)
+    # lpOverlapped must be provided despite the synchronous use of this method.
+    overlapped = LibC::OVERLAPPED.new
+    # unlock the entire file with offset 0 in overlapped and number of bytes set to max value
+    if 0 == LibC.UnlockFileEx(handle, 0, 0xFFFF_FFFF, 0xFFFF_FFFF, pointerof(overlapped))
+      raise IO::Error.from_winerror("UnLockFileEx")
+    end
+  end
+
+  private def system_fsync(flush_metadata = true) : Nil
+    if LibC.FlushFileBuffers(windows_handle) == 0
+      raise IO::Error.from_winerror("Error syncing file", target: self)
+    end
+  end
+
   private PIPE_BUFFER_SIZE = 8192
 
   def self.pipe(read_blocking, write_blocking)