added sqlite connection class (progress)

src/sql/backend_provider.cpp

@@ -0,0 +1,46 @@
+#include "matador/sql/backend_provider.hpp"
+
+#include <cstdint>
+#include <stdexcept>
+#include <utility>
+
+namespace matador::sql {
+backend_provider::backend_provider(std::string backends_path)
+: backends_path_(std::move(backends_path)) {}
+
+connection_impl *backend_provider::create_connection(const std::string &connection_type)
+{
+  auto it = backends_.find(connection_type);
+  if (it == backends_.end()) {
+    it = backends_.emplace(connection_type, backend_context{connection_type, backends_path_}).first;
+  }
+  return (*it->second.create_connection)();
+}
+
+const dialect &backend_provider::connection_dialect(const std::string &connection_type)
+{
+  auto it = backends_.find(connection_type);
+  if (it == backends_.end()) {
+    it = backends_.emplace(connection_type, backend_context{connection_type, backends_path_}).first;
+  }
+  return *(*it->second.get_dialect)();
+}
+
+backend_provider::backend_context::backend_context(const std::string &connection_type,
+                                                   const std::string &backends_path)
+{
+  if (!lib.load(backends_path + "matador-" + connection_type)) {
+    throw std::runtime_error("couldn't load library '" + connection_type + "'");
+  }
+
+  create_connection = reinterpret_cast<create_func>(reinterpret_cast<std::uintptr_t>(lib.function("create_database")));
+  destroy_connection = reinterpret_cast<destroy_func>(reinterpret_cast<std::uintptr_t>(lib.function("destroy_database")));
+  get_dialect = reinterpret_cast<dialect_func >(reinterpret_cast<std::uintptr_t>(lib.function("get_dialect")));
+}
+
+backend_provider::backend_context::~backend_context()
+{
+  lib.unload();
+}
+
+}

src/sql/dialect.cpp

@@ -3,6 +3,26 @@
 #include "matador/utils/string.hpp"
 
 namespace matador::sql {
+
+dialect::dialect(const dialect::token_to_string_map &token_replace_map, const dialect::data_type_to_string_map &data_type_replace_map)
+{
+  for (const auto &token : token_replace_map) {
+    tokens_[token.first] = token.second;
+  }
+
+  for (const auto &data_type : data_type_replace_map) {
+    data_types_[data_type.first] = data_type.second;
+  }
+}
+
+dialect::dialect(const dialect::data_type_to_string_map &data_type_replace_map)
+: dialect({}, data_type_replace_map)
+{}
+
+dialect::dialect(const dialect::token_to_string_map &token_replace_map)
+: dialect(token_replace_map, {})
+{}
+
 const std::string& dialect::token_at(dialect::token_t token) const
 {
   return tokens_.at(token);