Switch integer values to int32

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• All automated tests pass
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include/ccaosdb.h

@@ -19,6 +19,9 @@
  * <https://www.gnu.org/licenses/>.
  *
  */
+
+#include <cstdint> // for uint32_t
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -342,11 +345,11 @@ int caosdb_entity_entity_get_datatype(caosdb_entity_entity *entity, char **name,
                                       bool *is_list);
 int caosdb_entity_entity_get_unit(caosdb_entity_entity *entity, char **out);
 
-int caosdb_entity_entity_get_int_value(caosdb_entity_entity *entity, long *out);
+int caosdb_entity_entity_get_int_value(caosdb_entity_entity *entity, int32_t *out);
 int caosdb_entity_entity_get_double_value(caosdb_entity_entity *entity, double *out);
 int caosdb_entity_entity_get_boolean_value(caosdb_entity_entity *entity, bool *out);
 int caosdb_entity_entity_get_string_value(caosdb_entity_entity *entity, char **out);
-int caosdb_entity_entity_get_int_list_value_at(caosdb_entity_entity *entity, long *out,
+int caosdb_entity_entity_get_int_list_value_at(caosdb_entity_entity *entity, int32_t *out,
                                                const int index);
 int caosdb_entity_entity_get_double_list_value_at(caosdb_entity_entity *entity, double *out,
                                                   const int index);
@@ -384,11 +387,11 @@ int caosdb_entity_property_get_datatype(caosdb_entity_property *property, char *
                                         bool *is_list);
 int caosdb_entity_property_get_unit(caosdb_entity_property *property, char **out);
 
-int caosdb_entity_property_get_int_value(caosdb_entity_property *property, long *out);
+int caosdb_entity_property_get_int_value(caosdb_entity_property *property, int32_t *out);
 int caosdb_entity_property_get_double_value(caosdb_entity_property *property, double *out);
 int caosdb_entity_property_get_boolean_value(caosdb_entity_property *property, bool *out);
 int caosdb_entity_property_get_string_value(caosdb_entity_property *property, char **out);
-int caosdb_entity_property_get_int_list_value_at(caosdb_entity_property *property, long *out,
+int caosdb_entity_property_get_int_list_value_at(caosdb_entity_property *property, int32_t *out,
                                                  const int index);
 int caosdb_entity_property_get_double_list_value_at(caosdb_entity_property *property, double *out,
                                                     const int index);
@@ -426,11 +429,11 @@ int caosdb_entity_entity_set_datatype(caosdb_entity_entity *entity, const char *
                                       const bool is_ref, const bool is_list);
 int caosdb_entity_entity_set_unit(caosdb_entity_entity *entity, const char *unit);
 // TODO(fspreck) replace by more specific setters
-int caosdb_entity_entity_set_int_value(caosdb_entity_entity *entity, const long value);
+int caosdb_entity_entity_set_int_value(caosdb_entity_entity *entity, const int32_t value);
 int caosdb_entity_entity_set_double_value(caosdb_entity_entity *entity, const double value);
 int caosdb_entity_entity_set_boolean_value(caosdb_entity_entity *entity, const bool value);
 int caosdb_entity_entity_set_string_value(caosdb_entity_entity *entity, const char *value);
-int caosdb_entity_entity_set_int_list_value(caosdb_entity_entity *entity, const long *value,
+int caosdb_entity_entity_set_int_list_value(caosdb_entity_entity *entity, const int32_t *value,
                                             const int length);
 int caosdb_entity_entity_set_double_list_value(caosdb_entity_entity *entity, const double *value,
                                                const int length);
@@ -455,12 +458,12 @@ int caosdb_entity_property_set_datatype(caosdb_entity_property *property, const
 int caosdb_entity_property_set_importance(caosdb_entity_property *property, const char *importance);
 int caosdb_entity_property_set_unit(caosdb_entity_property *property, const char *unit);
 
-int caosdb_entity_property_set_int_value(caosdb_entity_property *property, const long value);
+int caosdb_entity_property_set_int_value(caosdb_entity_property *property, const int32_t value);
 int caosdb_entity_property_set_double_value(caosdb_entity_property *property, const double value);
 int caosdb_entity_property_set_boolean_value(caosdb_entity_property *property, const bool value);
 int caosdb_entity_property_set_string_value(caosdb_entity_property *property, const char *value);
-int caosdb_entity_property_set_int_list_value(caosdb_entity_property *property, const long *value,
-                                              const int length);
+int caosdb_entity_property_set_int_list_value(caosdb_entity_property *property,
+                                              const int32_t *value, const int length);
 int caosdb_entity_property_set_double_list_value(caosdb_entity_property *property,
                                                  const double *value, const int length);
 int caosdb_entity_property_set_boolean_list_value(caosdb_entity_property *property,