ISAR/libmdbx
3
0
Fork 0
mirror of https://github.com/isar/libmdbx.git synced 2025-09-16 03:32:19 +08:00
Code Issues Packages Projects Releases Wiki Activity

mdbx: workaround for broken DEFINE_ENUM_FLAG_OPERATORS from Windows SDK.

Browse Source 
Change-Id: I5335c72061b7c5b6b29c683061a5da95544b9753
This commit is contained in:
Leonid Yuriev
2020-10-10 20:07:00 +03:00
parent 1d71c677f6
commit de1856a73c
3 changed files with 49 additions and 16 deletions
Download Patch File Download Diff File Expand all files Collapse all files

48
mdbx.h
View File

@@ -440,8 +440,27 @@ typedef mode_t mdbx_mode_t;
#endif
#endif /* MDBX_PRINTF_ARGS */
/* Oh, below are some songs and dances since:
* - C++ requires explicit definition of the necessary operators.
* - the proper implementation of DEFINE_ENUM_FLAG_OPERATORS for C++ required
* the constexpr feature which is broken in most old compilers;
* - DEFINE_ENUM_FLAG_OPERATORS may be defined broken as in the Windows SDK. */
#ifndef DEFINE_ENUM_FLAG_OPERATORS
#if defined(__cplusplus)
#ifdef __cplusplus
#if !defined(__cpp_constexpr) || __cpp_constexpr < 200704L || \
(defined(__LCC__) && __LCC__ < 124) || \
(defined(__GNUC__) && (__GNUC__ * 100 + __GNUC_MINOR__ < 407) && \
!defined(__clang__) && !defined(__LCC__)) || \
(defined(_MSC_VER) && _MSC_VER < 1910) || \
(defined(__clang__) && __clang_major__ < 4)
/* The constexpr feature is not available or (may be) broken */
#define CONSTEXPR_ENUM_FLAGS_OPERATIONS 0
#else
/* C always allows these operators for enums */
#define CONSTEXPR_ENUM_FLAGS_OPERATIONS 1
#endif /* __cpp_constexpr */
/// Define operator overloads to enable bit operations on enum values that are
/// used to define flags (based on Microsoft's DEFINE_ENUM_FLAG_OPERATORS).
#define DEFINE_ENUM_FLAG_OPERATORS(ENUM) \
@@ -462,10 +481,23 @@ typedef mode_t mdbx_mode_t;
} \
MDBX_CXX14_CONSTEXPR ENUM &operator^=(ENUM &a, ENUM b) { return a = a ^ b; } \
}
#else /* __cplusplus */
#define DEFINE_ENUM_FLAG_OPERATORS(ENUM) /* nope, C allows these operators */
#endif /* !__cplusplus */
#endif /* DEFINE_ENUM_FLAG_OPERATORS */
#else /* __cplusplus */
/* nope for C since it always allows these operators for enums */
#define DEFINE_ENUM_FLAG_OPERATORS(ENUM)
#define CONSTEXPR_ENUM_FLAGS_OPERATIONS 1
#endif /* !__cplusplus */
#elif !defined(CONSTEXPR_ENUM_FLAGS_OPERATIONS)
#ifdef __cplusplus
/* DEFINE_ENUM_FLAG_OPERATORS may be defined broken as in the Windows SDK */
#define CONSTEXPR_ENUM_FLAGS_OPERATIONS 0
#else
/* C always allows these operators for enums */
#define CONSTEXPR_ENUM_FLAGS_OPERATIONS 1
#endif
#endif /* DEFINE_ENUM_FLAG_OPERATORS */
/** @} end of Common Macros */
@@ -1251,10 +1283,10 @@ enum MDBX_txn_flags_t {
* will be ready for use with \ref mdbx_txn_renew(). This flag allows to
* preallocate memory and assign a reader slot, thus avoiding these operations
* at the next start of the transaction. */
#if defined(__cplusplus) && !defined(__cpp_constexpr) && !defined(DOXYGEN)
MDBX_TXN_RDONLY_PREPARE = uint32_t(MDBX_RDONLY) | uint32_t(MDBX_NOMEMINIT),
#else
#if CONSTEXPR_ENUM_FLAGS_OPERATIONS || defined(DOXYGEN)
MDBX_TXN_RDONLY_PREPARE = MDBX_RDONLY | MDBX_NOMEMINIT,
#else
MDBX_TXN_RDONLY_PREPARE = uint32_t(MDBX_RDONLY) | uint32_t(MDBX_NOMEMINIT),
#endif
/** Do not block when starting a write transaction. */