mdbx++: Initial C++ API (some extra methods are not implemented).

Change-Id: I0478d0c94dcd12b52916e87815e5731817407c3c

test/CMakeLists.txt

@@ -27,30 +27,6 @@ add_executable(mdbx_test
   nested.cc
   )
 
-list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_20 HAS_CXX20)
-list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_17 HAS_CXX17)
-list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_14 HAS_CXX14)
-list(FIND CMAKE_CXX_COMPILE_FEATURES cxx_std_11 HAS_CXX11)
-if(NOT DEFINED MDBX_CXX_STANDARD)
-  if(DEFINED CMAKE_CXX_STANDARD)
-    set(MDBX_CXX_STANDARD ${CMAKE_CXX_STANDARD})
-  elseif(NOT HAS_CXX20 LESS 0)
-    set(MDBX_CXX_STANDARD 20)
-  elseif(NOT HAS_CXX17 LESS 0)
-    set(MDBX_CXX_STANDARD 17)
-  elseif(NOT HAS_CXX14 LESS 0)
-    set(MDBX_CXX_STANDARD 14)
-  elseif(NOT HAS_CXX11 LESS 0)
-    set(MDBX_CXX_STANDARD 11)
-  endif()
-endif()
-if(MDBX_CXX_STANDARD)
-  message(STATUS "Use C++${MDBX_CXX_STANDARD} for libmdbx")
-  if(NOT SUBPROJECT OR NOT DEFINED CMAKE_CXX_STANDARD)
-    set(CMAKE_CXX_STANDARD ${MDBX_CXX_STANDARD})
-  endif()
-endif()
-
 if(MDBX_CXX_STANDARD)
   set_target_properties(mdbx_test PROPERTIES
     CXX_STANDARD ${MDBX_CXX_STANDARD} CXX_STANDARD_REQUIRED ON)

test/log.cc

@@ -31,14 +31,15 @@ const char *test_strerror(int errnum) {
   return mdbx_strerror_r(errnum, buf, sizeof(buf));
 }
 
-void __noreturn failure_perror(const char *what, int errnum) {
+__noreturn void failure_perror(const char *what, int errnum) {
   failure("%s failed: %s (%d)\n", what, test_strerror(errnum), errnum);
 }
 
 //-----------------------------------------------------------------------------
 
 static void mdbx_logger(MDBX_log_level_t priority, const char *function,
-                        int line, const char *msg, va_list args) {
+                        int line, const char *msg,
+                        va_list args) cxx17_noexcept {
   if (!function)
     function = "unknown";
 

test/log.h

@@ -17,9 +17,9 @@
 #include "base.h"
 #include "chrono.h"
 
-void __noreturn usage(void);
-void __noreturn __printf_args(1, 2) failure(const char *fmt, ...);
-void __noreturn failure_perror(const char *what, int errnum);
+__noreturn void usage(void);
+__noreturn void __printf_args(1, 2) failure(const char *fmt, ...);
+__noreturn void failure_perror(const char *what, int errnum);
 const char *test_strerror(int errnum);
 
 namespace logging {

test/main.cc

@@ -19,7 +19,7 @@
 #include <sys/time.h>
 #endif /* !Windows */
 
-void __noreturn usage(void) {
+__noreturn void usage(void) {
   puts(
       "usage:\n"
       "  --help or -h              Show this text\n"

test/osal-unix.cc

@@ -16,6 +16,7 @@
 
 #if !(defined(_WIN32) || defined(_WIN64))
 
+#include <atomic>
 #include <pthread.h>
 #include <signal.h>
 #include <sys/mman.h>
@@ -309,7 +310,7 @@ bool actor_config::osal_deserialize(const char *str, const char *end,
 
 static pid_t overlord_pid;
 
-static std::atomic<int> sigusr1_head, sigusr2_head;
+static std::atomic_int sigusr1_head, sigusr2_head;
 static void handler_SIGUSR(int signum) {
   switch (signum) {
   case SIGUSR1:
@@ -337,7 +338,7 @@ bool osal_progress_push(bool active) {
 
 static std::unordered_map<pid_t, actor_status> childs;
 
-static std::atomic<int> sigalarm_head;
+static std::atomic_int sigalarm_head;
 static void handler_SIGCHLD(int signum) {
   if (signum == SIGALRM)
     ++sigalarm_head;

test/test.cc

@@ -80,7 +80,7 @@ const char *keygencase2str(const keygen_case keycase) {
 
 int testcase::oom_callback(MDBX_env *env, mdbx_pid_t pid, mdbx_tid_t tid,
                            uint64_t txn, unsigned gap, size_t space,
-                           int retry) {
+                           int retry) cxx17_noexcept {
 
   testcase *self = (testcase *)mdbx_env_get_userctx(env);
 
@@ -530,7 +530,8 @@ void testcase::db_table_close(MDBX_dbi handle) {
 void testcase::checkdata(const char *step, MDBX_dbi handle, MDBX_val key2check,
                          MDBX_val expected_valued) {
   MDBX_val actual_value = expected_valued;
-  int rc = mdbx_get_nearest(txn_guard.get(), handle, &key2check, &actual_value);
+  int rc = mdbx_get_equal_or_great(txn_guard.get(), handle, &key2check,
+                                   &actual_value);
   if (unlikely(rc != MDBX_SUCCESS))
     failure_perror(step, rc);
   if (!is_samedata(&actual_value, &expected_valued))

test/test.h

@@ -167,7 +167,8 @@ protected:
   int remove(const keygen::buffer &akey, const keygen::buffer &adata);
 
   static int oom_callback(MDBX_env *env, mdbx_pid_t pid, mdbx_tid_t tid,
-                          uint64_t txn, unsigned gap, size_t space, int retry);
+                          uint64_t txn, unsigned gap, size_t space,
+                          int retry) cxx17_noexcept;
 
   MDBX_env_flags_t actual_env_mode{MDBX_ENV_DEFAULTS};
   bool is_nested_txn_available() const {