Bug 792105 - Startup takes several minutes, take two.

First, remove the unnecessary locale push & pop on <CT_TIME64>load.

Second, the registry accesses were caused by using g_win32_get_locale
to convert the Microsoft locale strings to POSIX ones. We don't care
what kind of string we get as long as we can pass it back to setlocale,
so remove that.

Third, gnc_push/pop_locale were used only in backend/dbi in a
very limited way and did much more than was necessary, so
convert them to C++ inlines in gnc-backend-dbi.hpp that does
only what we need them to.

libgnucash/backend/dbi/gnc-backend-dbi.cpp

@@ -1177,7 +1177,7 @@ dbi_library_test (dbi_conn conn)
         return GNC_DBI_FAIL_SETUP;
     }
     dbi_result_free (result);
-    gnc_push_locale (LC_NUMERIC, "C");
+    auto locale = gnc_push_locale (LC_NUMERIC, "C");
     result = dbi_conn_query (conn, "SELECT * FROM numtest");
     if (result == nullptr)
     {
@@ -1186,7 +1186,7 @@ dbi_library_test (dbi_conn conn)
         PWARN ("Test_DBI_Library: Failed to retrieve test row into table: %s",
                errmsg);
         dbi_conn_query (conn, "DROP TABLE numtest");
-        gnc_pop_locale (LC_NUMERIC);
+        gnc_pop_locale (LC_NUMERIC, locale);
         return GNC_DBI_FAIL_SETUP;
     }
     while (dbi_result_next_row (result))
@@ -1196,7 +1196,7 @@ dbi_library_test (dbi_conn conn)
         resultdouble = dbi_result_get_double (result, "test_double");
     }
     dbi_conn_query (conn, "DROP TABLE numtest");
-    gnc_pop_locale (LC_NUMERIC);
+    gnc_pop_locale (LC_NUMERIC, locale);
     if (testlonglong != resultlonglong)
     {
         PWARN ("Test_DBI_Library: LongLong Failed %" PRId64 " != % " PRId64,

libgnucash/backend/dbi/gnc-backend-dbi.hpp

@@ -118,6 +118,21 @@ private:
     bool m_exists;         // Does the database exist?
 };
 
+/* locale-stack */
+inline std::string
+gnc_push_locale(const int category, const std::string locale)
+{
+    std::string retval(setlocale(category, nullptr));
+    setlocale(category, locale.c_str());
+    return retval;
+}
+
+inline void
+gnc_pop_locale(const int category, std::string locale)
+{
+    setlocale(category, locale.c_str());
+}
+
 /* external access required for tests */
 std::string adjust_sql_options_string(const std::string&);
 

libgnucash/backend/dbi/gnc-dbisqlconnection.cpp

@@ -252,7 +252,7 @@ GncDbiSqlConnection::execute_select_statement (const GncSqlStatementPtr& stmt)
     dbi_result result;
 
     DEBUG ("SQL: %s\n", stmt->to_sql());
-    gnc_push_locale (LC_NUMERIC, "C");
+    auto locale = gnc_push_locale (LC_NUMERIC, "C");
     do
     {
         init_error ();
@@ -261,7 +261,7 @@ GncDbiSqlConnection::execute_select_statement (const GncSqlStatementPtr& stmt)
     while (m_retry);
     if (result == nullptr)
         PERR ("Error executing SQL %s\n", stmt->to_sql());
-    gnc_pop_locale (LC_NUMERIC);
+    gnc_pop_locale (LC_NUMERIC, locale);
     return GncSqlResultPtr(new GncDbiSqlResult (this, result));
 }
 

libgnucash/backend/dbi/gnc-dbisqlresult.cpp

@@ -117,9 +117,9 @@ GncDbiSqlResult::IteratorImpl::get_float_at_col(const char* col) const
     if(type != DBI_TYPE_DECIMAL ||
        (attrs & DBI_DECIMAL_SIZEMASK) != DBI_DECIMAL_SIZE4)
         throw (std::invalid_argument{"Requested float from non-float column."});
-    gnc_push_locale (LC_NUMERIC, "C");
+    auto locale = gnc_push_locale (LC_NUMERIC, "C");
     auto retval =  dbi_result_get_float(m_inst->m_dbi_result, col);
-    gnc_pop_locale (LC_NUMERIC);
+    gnc_pop_locale (LC_NUMERIC, locale);
     return retval;
 }
 
@@ -131,9 +131,9 @@ GncDbiSqlResult::IteratorImpl::get_double_at_col(const char* col) const
     if(type != DBI_TYPE_DECIMAL ||
        (attrs & DBI_DECIMAL_SIZEMASK) != DBI_DECIMAL_SIZE8)
         throw (std::invalid_argument{"Requested double from non-double column."});
-    gnc_push_locale (LC_NUMERIC, "C");
+    auto locale = gnc_push_locale (LC_NUMERIC, "C");
     auto retval =  dbi_result_get_double(m_inst->m_dbi_result, col);
-    gnc_pop_locale (LC_NUMERIC);
+    gnc_pop_locale (LC_NUMERIC, locale);
     return retval;
 }
 
@@ -160,7 +160,6 @@ GncDbiSqlResult::IteratorImpl::get_time64_at_col (const char* col) const
     auto attrs = dbi_result_get_field_attribs (result, col);
     if (type != DBI_TYPE_DATETIME)
         throw (std::invalid_argument{"Requested time64 from non-time64 column."});
-    gnc_push_locale (LC_NUMERIC, "C");
 #if HAVE_LIBDBI_TO_LONGLONG
     /* A less evil hack than the one required by libdbi-0.8, but
      * still necessary to work around the same bug.
@@ -179,7 +178,6 @@ GncDbiSqlResult::IteratorImpl::get_time64_at_col (const char* col) const
 #endif //HAVE_LIBDBI_TO_LONGLONG
     if (retval < MINTIME || retval > MAXTIME)
         retval = 0;
-    gnc_pop_locale (LC_NUMERIC);
     return retval;
 }