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Diffstat (limited to 'mfbt/Types.h')
| -rw-r--r-- | mfbt/Types.h | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/mfbt/Types.h b/mfbt/Types.h new file mode 100644 index 0000000..f803586 --- /dev/null +++ b/mfbt/Types.h @@ -0,0 +1,136 @@ +/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ +/* 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 the integer types defined in C99's <stdint.h> (and the integer + * limit and constant macros, if compiling C code or if compiling C++ code and + * the right __STDC_*_MACRO has been defined for each). These are all usable + * throughout mfbt code, and throughout Mozilla code more generally. + */ +#include "mozilla/StandardInteger.h" + +/* Also expose size_t. */ +#include <stddef.h> + +/* Implement compiler and linker macros needed for APIs. */ + +/* + * MOZ_EXPORT_API is used to declare and define a method which is externally + * visible to users of the current library. It encapsulates various decorations + * needed to properly export the method's symbol. MOZ_EXPORT_DATA serves the + * same purpose for data. + * + * api.h: + * extern MOZ_EXPORT_API(int) MeaningOfLife(void); + * extern MOZ_EXPORT_DATA(int) LuggageCombination; + * + * api.c: + * MOZ_EXPORT_API(int) MeaningOfLife(void) { return 42; } + * MOZ_EXPORT_DATA(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) || defined(XP_OS2) +# define MOZ_EXPORT_API(type) __declspec(dllexport) type +# define MOZ_EXPORT_DATA(type) __declspec(dllexport) type +#else /* Unix */ +# ifdef HAVE_VISIBILITY_ATTRIBUTE +# define MOZ_EXTERNAL_VIS __attribute__((visibility("default"))) +# elif defined(__SUNPRO_C) || defined(__SUNPRO_CC) +# define MOZ_EXTERNAL_VIS __global +# else +# define MOZ_EXTERNAL_VIS +# endif +# define MOZ_EXPORT_API(type) MOZ_EXTERNAL_VIS type +# define MOZ_EXPORT_DATA(type) MOZ_EXTERNAL_VIS type +#endif + +/* + * Whereas implementers use MOZ_EXPORT_API and MOZ_EXPORT_DATA 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(x) x +# else +# define MOZ_IMPORT_API(x) __declspec(dllimport) x +# endif +#elif defined(XP_OS2) +# define MOZ_IMPORT_API(x) __declspec(dllimport) x +#else +# define MOZ_IMPORT_API(x) MOZ_EXPORT_API(x) +#endif + +#if defined(_WIN32) && !defined(__MWERKS__) +# define MOZ_IMPORT_DATA(x) __declspec(dllimport) x +#elif defined(XP_OS2) +# define MOZ_IMPORT_DATA(x) __declspec(dllimport) x +#else +# define MOZ_IMPORT_DATA(x) MOZ_EXPORT_DATA(x) +#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(type) MOZ_EXPORT_API(type) +# define MFBT_DATA(type) MOZ_EXPORT_DATA(type) +#else + /* + * When mozglue is linked in the program, we need the MFBT API symbols + * to be weak. + */ +# if defined(MOZ_GLUE_IN_PROGRAM) +# define MFBT_API(type) __attribute__((weak)) MOZ_IMPORT_API(type) +# define MFBT_DATA(type) __attribute__((weak)) MOZ_IMPORT_DATA(type) +# else +# define MFBT_API(type) MOZ_IMPORT_API(type) +# define MFBT_DATA(type) MOZ_IMPORT_DATA(type) +# 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_API(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 + +#endif /* mozilla_Types_h_ */ |