Store error message instead of error string

Resolves #187.

Author: zauguin

hdr/sqlite_modern_cpp.h

@@ -113,7 +113,7 @@ namespace sqlite {
 			sqlite3_stmt* tmp = nullptr;
 			const char *remaining;
 			hresult = sqlite3_prepare_v2(_db.get(), sql.data(), sql.length(), &tmp, &remaining);
-			if(hresult != SQLITE_OK) errors::throw_sqlite_error(hresult, sql);
+			if(hresult != SQLITE_OK) errors::throw_sqlite_error(hresult, sql, sqlite3_errmsg(_db.get()));
 			if(!std::all_of(remaining, sql.data() + sql.size(), [](char ch) {return std::isspace(ch);}))
 				throw errors::more_statements("Multiple semicolon separated statements are unsupported", sql);
 			return tmp;
@@ -214,7 +214,7 @@ namespace sqlite {
 					_binder = nullptr;
 					break;
 				default:
-					exceptions::throw_sqlite_error(result, _binder->sql());
+					exceptions::throw_sqlite_error(result, _binder->sql(), sqlite3_errmsg(_binder->_db.get()));
 			}
 			return *this;
 		}
@@ -387,7 +387,7 @@ namespace sqlite {
 			sqlite3* tmp = nullptr;
 			auto ret = sqlite3_open_v2(db_name.data(), &tmp, static_cast<int>(config.flags), config.zVfs);
 			_db = std::shared_ptr<sqlite3>(tmp, [=](sqlite3* ptr) { sqlite3_close_v2(ptr); }); // this will close the connection eventually when no longer needed.
-			if(ret != SQLITE_OK) errors::throw_sqlite_error(_db ? sqlite3_extended_errcode(_db.get()) : ret);
+			if(ret != SQLITE_OK) errors::throw_sqlite_error(_db ? sqlite3_extended_errcode(_db.get()) : ret, {}, sqlite3_errmsg(_db.get()));
 			sqlite3_extended_result_codes(_db.get(), true);
 			if(config.encoding == Encoding::UTF16)
 				*this << R"(PRAGMA encoding = "UTF-16";)";
@@ -430,7 +430,7 @@ namespace sqlite {
 					nullptr, nullptr, [](void* ptr){
 				delete static_cast<decltype(funcPtr)>(ptr);
 			}))
-				errors::throw_sqlite_error(result);
+				errors::throw_sqlite_error(result, {}, sqlite3_errmsg(_db.get()));
 		}
 
 		template <typename StepFunction, typename FinalFunction>
@@ -446,7 +446,7 @@ namespace sqlite {
 					[](void* ptr){
 				delete static_cast<decltype(funcPtr)>(ptr);
 			}))
-				errors::throw_sqlite_error(result);
+				errors::throw_sqlite_error(result, {}, sqlite3_errmsg(_db.get()));
 		}
 
 	};
@@ -505,7 +505,7 @@ namespace sqlite {
 		db._next_index(); --db._inx;
 		int result = bind_col_in_db(db._stmt.get(), val.index, std::forward<T>(val.value));
 		if(result != SQLITE_OK)
-			exceptions::throw_sqlite_error(result, db.sql());
+			exceptions::throw_sqlite_error(result, db.sql(), sqlite3_errmsg(db._db.get()));
 		return db;
 	}
 
@@ -516,14 +516,14 @@ namespace sqlite {
 			throw errors::unknown_binding("The given binding name is not valid for this statement", db.sql());
 		int result = bind_col_in_db(db._stmt.get(), index, std::forward<T>(val.value));
 		if(result != SQLITE_OK)
-			exceptions::throw_sqlite_error(result, db.sql());
+			exceptions::throw_sqlite_error(result, db.sql(), sqlite3_errmsg(db._db.get()));
 		return db;
 	}
 
 	template<typename T> database_binder &operator<<(database_binder& db, T&& val) {
 		int result = bind_col_in_db(db._stmt.get(), db._next_index(), std::forward<T>(val));
 		if(result != SQLITE_OK)
-			exceptions::throw_sqlite_error(result, db.sql());
+			exceptions::throw_sqlite_error(result, db.sql(), sqlite3_errmsg(db._db.get()));
 		return db;
 	}
 	// Convert the rValue binder to a reference and call first op<<, its needed for the call that creates the binder (be carefull of recursion here!)

hdr/sqlite_modern_cpp/errors.h

@@ -10,10 +10,11 @@ namespace sqlite {
 	class sqlite_exception: public std::runtime_error {
 	public:
 		sqlite_exception(const char* msg, str_ref sql, int code = -1): runtime_error(msg), code(code), sql(sql) {}
-		sqlite_exception(int code, str_ref sql): runtime_error(sqlite3_errstr(code)), code(code), sql(sql) {}
+		sqlite_exception(int code, str_ref sql, const char *msg = nullptr): runtime_error(msg ? msg : sqlite3_errstr(code)), code(code), sql(sql) {}
 		int get_code() const {return code & 0xFF;}
 		int get_extended_code() const {return code;}
 		std::string get_sql() const {return sql;}
+		const char *errstr() const {return code == -1 ? "Unknown error" : sqlite3_errstr(code);}
 	private:
 		int code;
 		std::string sql;
@@ -41,7 +42,7 @@ namespace sqlite {
 		class invalid_utf16: public sqlite_exception { using sqlite_exception::sqlite_exception; };
 		class unknown_binding: public sqlite_exception { using sqlite_exception::sqlite_exception; };
 
-		static void throw_sqlite_error(const int& error_code, str_ref sql = "") {
+		static void throw_sqlite_error(const int& error_code, str_ref sql = "", const char *errmsg = nullptr) {
 			switch(error_code & 0xFF) {
 #define SQLITE_MODERN_CPP_ERROR_CODE(NAME,name,derived)     \
 				case SQLITE_ ## NAME: switch(error_code) {          \
@@ -57,11 +58,11 @@ namespace sqlite {
 #endif
 
 #define SQLITE_MODERN_CPP_ERROR_CODE_EXTENDED(BASE,SUB,base,sub) \
-					case SQLITE_ ## BASE ## _ ## SUB: throw base ## _ ## sub(error_code, sql);
+					case SQLITE_ ## BASE ## _ ## SUB: throw base ## _ ## sub(error_code, sql, errmsg);
 #include "lists/error_codes.h"
 #undef SQLITE_MODERN_CPP_ERROR_CODE_EXTENDED
 #undef SQLITE_MODERN_CPP_ERROR_CODE
-				default: throw sqlite_exception(error_code, sql);
+				default: throw sqlite_exception(error_code, sql, errmsg);
 			}
 		}
 	}