[glib/wip/ghandle: 3/16] gpoll: introduce new ghandle type

[Ryan Lortie <desrt src gnome org>]

commit 19499579f9eb3de59e6ba75e430f9189ff818c3c
Author: Ryan Lortie <desrt desrt ca>
Date:   Thu Dec 18 13:23:05 2014 -0500

    gpoll: introduce new ghandle type
    
    We've long discussed having a ghandle type corresponding to HANDLE on windows
    and an int (fd) elsewhere.  Let's add that now.
    
    We continue to maintain the 'fd' field as being an integer on Windows in order
    to avoid warnings about implicit casts in existing software.  'ghandleint' was
    introduced for that purpose.

 docs/reference/glib/glib-sections.txt |    4 +++
 glib/docs.c                           |   38 +++++++++++++++++++++++++++++++++
 glib/gpoll.h                          |   26 ++++++++++++++++------
 3 files changed, 61 insertions(+), 7 deletions(-)
---
diff --git a/docs/reference/glib/glib-sections.txt b/docs/reference/glib/glib-sections.txt
index d34600f..aaac897 100644
--- a/docs/reference/glib/glib-sections.txt
+++ b/docs/reference/glib/glib-sections.txt
@@ -544,6 +544,10 @@ g_child_watch_add
 g_child_watch_add_full
 
 <SUBSECTION>
+ghandle
+ghandleint
+%G_HANDLE_NULL
+g_handle_is_valid
 GPollFD
 g_poll
 G_POLLFD_FORMAT
diff --git a/glib/docs.c b/glib/docs.c
index 43c9f27..abccc6b 100644
--- a/glib/docs.c
+++ b/glib/docs.c
@@ -2370,5 +2370,43 @@
  * Since: 2.6
  */
  
+/* ghandle {{{1 */
+/**
+ * ghandle:
+ *
+ * Corresponds to a HANDLE on Windows and a file descriptor elsewhere.
+ *
+ * Since: 2.44
+ */
+
+/**
+ * ghandleint:
+ *
+ * An integer with the same size as #ghandle.  Used in #GPollFD as the
+ * 'fd' field.
+ *
+ * Since: 2.44
+ */
+
+/**
+ * G_HANDLE_INVALID:
+ *
+ * A value used to denote an invalid handle.  Can always be safely
+ * compared to #ghandle.
+ *
+ * See also g_handle_is_valid().
+ *
+ * Since: 2.44
+ */
+
+/**
+ * g_handle_is_valid:
+ * @handle: a #ghandle
+ *
+ * Checks if a #ghandle is valid (ie: not equal to G_HANDLE_NULL).
+ *
+ * Since: 2.44
+ */
+
  /* Epilogue {{{1 */
 /* vim: set foldmethod=marker: */
diff --git a/glib/gpoll.h b/glib/gpoll.h
index f28e3c5..44f33ec 100644
--- a/glib/gpoll.h
+++ b/glib/gpoll.h
@@ -74,6 +74,24 @@ typedef gint    (*GPollFunc)    (GPollFD *ufds,
                                  guint    nfsd,
                                  gint     timeout_);
 
+#ifdef G_OS_WIN32
+typedef gintptr ghandleint;
+typedef gpointer ghandle;
+#define G_HANDLE_NULL (NULL)
+#else
+typedef gint ghandleint;
+typedef gint ghandle;
+#define G_HANDLE_NULL (-1)
+#endif
+
+G_STATIC_ASSERT(sizeof (ghandle) == sizeof (ghandleint));
+
+static inline gboolean
+g_handle_is_valid (ghandle handle)
+{
+  return handle != G_HANDLE_NULL;
+}
+
 /**
  * GPollFD:
  * @fd: the file descriptor to poll (or a HANDLE on Win32)
@@ -89,13 +107,7 @@ typedef gint    (*GPollFunc)    (GPollFD *ufds,
  */
 struct _GPollFD
 {
-#if defined (G_OS_WIN32) && GLIB_SIZEOF_VOID_P == 8
-#ifndef __GTK_DOC_IGNORE__
-  gint64       fd;
-#endif
-#else
-  gint         fd;
-#endif
+  ghandleint    fd;
   gushort      events;
   gushort      revents;
 };