import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

mfbt/Types.h

@@ -0,0 +1,134 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/* mfbt foundational types and macros. */
+
+#ifndef mozilla_Types_h
+#define mozilla_Types_h
+
+/*
+ * This header must be valid C and C++, includable by code embedding either
+ * SpiderMonkey or Gecko.
+ */
+
+/* Expose all <stdint.h> types and size_t. */
+#include <stddef.h>
+#include <stdint.h>
+
+/* Implement compiler and linker macros needed for APIs. */
+
+/*
+ * MOZ_EXPORT is used to declare and define a symbol or type which is externally
+ * visible to users of the current library.  It encapsulates various decorations
+ * needed to properly export the method's symbol.
+ *
+ *   api.h:
+ *     extern MOZ_EXPORT int MeaningOfLife(void);
+ *     extern MOZ_EXPORT int LuggageCombination;
+ *
+ *   api.c:
+ *     int MeaningOfLife(void) { return 42; }
+ *     int LuggageCombination = 12345;
+ *
+ * If you are merely sharing a method across files, just use plain |extern|.
+ * These macros are designed for use by library interfaces -- not for normal
+ * methods or data used cross-file.
+ */
+#if defined(WIN32)
+#  define MOZ_EXPORT   __declspec(dllexport)
+#else /* Unix */
+#  ifdef HAVE_VISIBILITY_ATTRIBUTE
+#    define MOZ_EXPORT       __attribute__((visibility("default")))
+#  elif defined(__SUNPRO_C) || defined(__SUNPRO_CC)
+#    define MOZ_EXPORT      __global
+#  else
+#    define MOZ_EXPORT /* nothing */
+#  endif
+#endif
+
+
+/*
+ * Whereas implementers use MOZ_EXPORT to declare and define library symbols,
+ * users use MOZ_IMPORT_API and MOZ_IMPORT_DATA to access them.  Most often the
+ * implementer of the library will expose an API macro which expands to either
+ * the export or import version of the macro, depending upon the compilation
+ * mode.
+ */
+#ifdef _WIN32
+#  if defined(__MWERKS__)
+#    define MOZ_IMPORT_API /* nothing */
+#  else
+#    define MOZ_IMPORT_API __declspec(dllimport)
+#  endif
+#else
+#  define MOZ_IMPORT_API MOZ_EXPORT
+#endif
+
+#if defined(_WIN32) && !defined(__MWERKS__)
+#  define MOZ_IMPORT_DATA  __declspec(dllimport)
+#else
+#  define MOZ_IMPORT_DATA  MOZ_EXPORT
+#endif
+
+/*
+ * Consistent with the above comment, the MFBT_API and MFBT_DATA macros expose
+ * export mfbt declarations when building mfbt, and they expose import mfbt
+ * declarations when using mfbt.
+ */
+#if defined(IMPL_MFBT)
+#  define MFBT_API     MOZ_EXPORT
+#  define MFBT_DATA    MOZ_EXPORT
+#else
+  /*
+   * On linux mozglue is linked in the program and we link libxul.so with
+   * -z,defs. Normally that causes the linker to reject undefined references in
+   * libxul.so, but as a loophole it allows undefined references to weak
+   * symbols. We add the weak attribute to the import version of the MFBT API
+   * macros to exploit this.
+   */
+#  if defined(MOZ_GLUE_IN_PROGRAM)
+#    define MFBT_API   __attribute__((weak)) MOZ_IMPORT_API
+#    define MFBT_DATA  __attribute__((weak)) MOZ_IMPORT_DATA
+#  else
+#    define MFBT_API   MOZ_IMPORT_API
+#    define MFBT_DATA  MOZ_IMPORT_DATA
+#  endif
+#endif
+
+/*
+ * C symbols in C++ code must be declared immediately within |extern "C"|
+ * blocks.  However, in C code, they need not be declared specially.  This
+ * difference is abstracted behind the MOZ_BEGIN_EXTERN_C and MOZ_END_EXTERN_C
+ * macros, so that the user need not know whether he is being used in C or C++
+ * code.
+ *
+ *   MOZ_BEGIN_EXTERN_C
+ *
+ *   extern MOZ_EXPORT int MostRandomNumber(void);
+ *   ...other declarations...
+ *
+ *   MOZ_END_EXTERN_C
+ *
+ * This said, it is preferable to just use |extern "C"| in C++ header files for
+ * its greater clarity.
+ */
+#ifdef __cplusplus
+#  define MOZ_BEGIN_EXTERN_C    extern "C" {
+#  define MOZ_END_EXTERN_C      }
+#else
+#  define MOZ_BEGIN_EXTERN_C
+#  define MOZ_END_EXTERN_C
+#endif
+
+/*
+ * GCC's typeof is available when decltype is not.
+ */
+#if defined(__GNUC__) && defined(__cplusplus) && \
+  !defined(__GXX_EXPERIMENTAL_CXX0X__) && __cplusplus < 201103L
+#  define decltype __typeof__
+#endif
+
+#endif /* mozilla_Types_h */