LXR qemu/include/glib-compat.h

   1/*
   2 * GLIB Compatibility Functions
   3 *
   4 * Copyright IBM, Corp. 2013
   5 *
   6 * Authors:
   7 *  Anthony Liguori   <aliguori@us.ibm.com>
   8 *  Michael Tokarev   <mjt@tls.msk.ru>
   9 *  Paolo Bonzini     <pbonzini@redhat.com>
  10 *
  11 * This work is licensed under the terms of the GNU GPL, version 2 or later.
  12 * See the COPYING file in the top-level directory.
  13 *
  14 */
  15
  16#ifndef QEMU_GLIB_COMPAT_H
  17#define QEMU_GLIB_COMPAT_H
  18
  19/* Ask for warnings for anything that was marked deprecated in
  20 * the defined version, or before. It is a candidate for rewrite.
  21 */
  22#define GLIB_VERSION_MIN_REQUIRED GLIB_VERSION_2_48
  23
  24/* Ask for warnings if code tries to use function that did not
  25 * exist in the defined version. These risk breaking builds
  26 */
  27#define GLIB_VERSION_MAX_ALLOWED GLIB_VERSION_2_48
  28
  29#pragma GCC diagnostic push
  30#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
  31
  32#include <glib.h>
  33
  34/*
  35 * Note that because of the GLIB_VERSION_MAX_ALLOWED constant above, allowing
  36 * use of functions from newer GLib via this compat header needs a little
  37 * trickery to prevent warnings being emitted.
  38 *
  39 * Consider a function from newer glib-X.Y that we want to use
  40 *
  41 *    int g_foo(const char *wibble)
  42 *
  43 * We must define a static inline function with the same signature that does
  44 * what we need, but with a "_qemu" suffix e.g.
  45 *
  46 * static inline void g_foo_qemu(const char *wibble)
  47 * {
  48 *     #if GLIB_CHECK_VERSION(X, Y, 0)
  49 *        g_foo(wibble)
  50 *     #else
  51 *        g_something_equivalent_in_older_glib(wibble);
  52 *     #endif
  53 * }
  54 *
  55 * The #pragma at the top of this file turns off -Wdeprecated-declarations,
  56 * ensuring this wrapper function impl doesn't trigger the compiler warning
  57 * about using too new glib APIs. Finally we can do
  58 *
  59 *   #define g_foo(a) g_foo_qemu(a)
  60 *
  61 * So now the code elsewhere in QEMU, which *does* have the
  62 * -Wdeprecated-declarations warning active, can call g_foo(...) as normal,
  63 * without generating warnings.
  64 */
  65
  66#if defined(_WIN32) && !GLIB_CHECK_VERSION(2, 50, 0)
  67/*
  68 * g_poll has a problem on Windows when using
  69 * timeouts < 10ms, so use wrapper.
  70 */
  71#define g_poll(fds, nfds, timeout) g_poll_fixed(fds, nfds, timeout)
  72gint g_poll_fixed(GPollFD *fds, guint nfds, gint timeout);
  73#endif
  74
  75#pragma GCC diagnostic pop
  76
  77#endif
  78