should be it

external/duckdb/test/api/capi/capi_file_system.cpp

@@ -0,0 +1,159 @@
+#include "capi_tester.hpp"
+
+using namespace duckdb;
+using namespace std;
+
+static void test_file_system(duckdb_file_system fs, string file_name) {
+	REQUIRE(fs != nullptr);
+
+	duckdb_state state = DuckDBSuccess;
+	duckdb_file_handle file;
+
+	auto file_path = TestDirectoryPath() + "/" + file_name;
+
+	auto options = duckdb_create_file_open_options();
+	state = duckdb_file_open_options_set_flag(options, DUCKDB_FILE_FLAG_WRITE, true);
+	REQUIRE(state == DuckDBSuccess);
+	state = duckdb_file_open_options_set_flag(options, DUCKDB_FILE_FLAG_READ, true);
+	REQUIRE(state == DuckDBSuccess);
+
+	// Try to open non-existing file without create flag
+	state = duckdb_file_system_open(fs, file_path.c_str(), options, &file);
+	REQUIRE(state != DuckDBSuccess);
+	auto error_data = duckdb_file_system_error_data(fs);
+	auto error_type = duckdb_error_data_error_type(error_data);
+	REQUIRE(error_type == DUCKDB_ERROR_IO);
+	duckdb_destroy_error_data(&error_data);
+
+	// Try to write to a null file handle
+	auto failed_bytes_written = duckdb_file_handle_write(file, "data", 4);
+	REQUIRE(failed_bytes_written == -1);
+	auto file_error_data = duckdb_file_handle_error_data(file);
+	auto has_error = duckdb_error_data_has_error(file_error_data);
+	REQUIRE(has_error == false);
+	duckdb_destroy_error_data(&file_error_data);
+
+	// Set create flag
+	state = duckdb_file_open_options_set_flag(options, DUCKDB_FILE_FLAG_CREATE, true);
+	REQUIRE(state == DuckDBSuccess);
+
+	// Create and open a file
+	state = duckdb_file_system_open(fs, file_path.c_str(), options, &file);
+	REQUIRE(state == DuckDBSuccess);
+	REQUIRE(file != nullptr);
+
+	// Write to the file
+	const char *data = "Hello, DuckDB File System!";
+	auto bytes_written = duckdb_file_handle_write(file, data, strlen(data));
+	REQUIRE(bytes_written == (int64_t)strlen(data));
+	auto position = duckdb_file_handle_tell(file);
+	REQUIRE(position == bytes_written);
+	auto size = duckdb_file_handle_size(file);
+	REQUIRE(size == bytes_written);
+
+	// Sync
+	state = duckdb_file_handle_sync(file);
+
+	// Seek to the beginning
+	state = duckdb_file_handle_seek(file, 0);
+	REQUIRE(state == DuckDBSuccess);
+	position = duckdb_file_handle_tell(file);
+	REQUIRE(position == 0);
+
+	// Read from the file
+	char buffer[30];
+	memset(buffer, 0, sizeof(buffer));
+	auto bytes_read = duckdb_file_handle_read(file, buffer, sizeof(buffer) - 1);
+	REQUIRE(bytes_read == bytes_written);
+	REQUIRE(strcmp(buffer, data) == 0);
+	position = duckdb_file_handle_tell(file);
+	REQUIRE(position == bytes_read);
+	size = duckdb_file_handle_size(file);
+	REQUIRE(size == bytes_written);
+
+	// Seek to the end
+	state = duckdb_file_handle_seek(file, bytes_written);
+	REQUIRE(state == DuckDBSuccess);
+	position = duckdb_file_handle_tell(file);
+	REQUIRE(position == bytes_written);
+	size = duckdb_file_handle_size(file);
+	REQUIRE(size == bytes_written);
+
+	// Try to read from the end of the file
+	memset(buffer, 0, sizeof(buffer));
+	bytes_read = duckdb_file_handle_read(file, buffer, sizeof(buffer) - 1);
+	REQUIRE(bytes_read == 0); // EOF
+	position = duckdb_file_handle_tell(file);
+	REQUIRE(position == bytes_written);
+	size = duckdb_file_handle_size(file);
+	REQUIRE(size == bytes_written);
+
+	// Seek back to the beginning
+	state = duckdb_file_handle_seek(file, 0);
+	REQUIRE(state == DuckDBSuccess);
+	position = duckdb_file_handle_tell(file);
+	REQUIRE(position == 0);
+	size = duckdb_file_handle_size(file);
+	REQUIRE(size == bytes_written);
+
+	// Close the file
+	duckdb_file_handle_close(file);
+	duckdb_destroy_file_handle(&file);
+
+	// Open file again for reading
+	state = duckdb_file_system_open(fs, file_path.c_str(), options, &file);
+	REQUIRE(state == DuckDBSuccess);
+	REQUIRE(file != nullptr);
+	size = duckdb_file_handle_size(file);
+	REQUIRE(size == bytes_written);
+	// Check that the data is still there
+	memset(buffer, 0, sizeof(buffer));
+	bytes_read = duckdb_file_handle_read(file, buffer, sizeof(buffer) - 1);
+	REQUIRE(bytes_read == bytes_written);
+	REQUIRE(strcmp(buffer, data) == 0);
+	position = duckdb_file_handle_tell(file);
+	REQUIRE(position == bytes_read);
+	size = duckdb_file_handle_size(file);
+	REQUIRE(size == bytes_written);
+
+	// Close the file again
+	duckdb_file_handle_close(file);
+	duckdb_destroy_file_handle(&file);
+
+	duckdb_destroy_file_open_options(&options);
+
+	REQUIRE(file == nullptr);
+	REQUIRE(options == nullptr);
+
+	// Try destroy again for good measure
+	duckdb_destroy_file_handle(&file);
+	duckdb_destroy_file_open_options(&options);
+
+	REQUIRE(file == nullptr);
+	REQUIRE(options == nullptr);
+}
+
+TEST_CASE("Test File System in C API", "[capi]") {
+	CAPITester tester;
+	duckdb_client_context context;
+	duckdb_file_system fs;
+	duckdb::unique_ptr<CAPIResult> result;
+
+	REQUIRE(tester.OpenDatabase(nullptr));
+
+	// get a file system from the client context
+	duckdb_connection_get_client_context(tester.connection, &context);
+	fs = duckdb_client_context_get_file_system(context);
+	REQUIRE(fs != nullptr);
+
+	test_file_system(fs, "test_file_capi_1.txt");
+
+	duckdb_destroy_file_system(&fs);
+	REQUIRE(fs == nullptr);
+
+	duckdb_destroy_client_context(&context);
+
+	// Try to destory fs again
+	duckdb_destroy_file_system(&fs);
+	REQUIRE(fs == nullptr);
+}