adding some moar

CMakeLists.txt

@@ -1,29 +1,33 @@
-cmake_minimum_required(VERSION 3.5...3.29)
+cmake_minimum_required(VERSION 2.8)
 
 set(CMAKE_CXX_STANDARD "11" CACHE STRING "C++ standard to enforce")
 
+###
+# Configuration
+###
 if(NOT DEFINED MINIMUM_DUCKDB_VERSION_MAJOR OR
         NOT DEFINED MINIMUM_DUCKDB_VERSION_MINOR OR
         NOT DEFINED MINIMUM_DUCKDB_VERSION_PATCH)
     message(FATAL_ERROR "DuckDB minimum version is required")
 endif()
-
 if(NOT DEFINED EXTENSION_NAME)
     message(FATAL_ERROR "DuckDB extension name is required")
 endif()
-
-project(${EXTENSION_NAME})
-
-#message(FATAL_ERROR "-DDUCKDB_EXTENSION_API_VERSION_MAJOR=${MINIMUM_DUCKDB_VERSION_MINOR}")
 add_definitions(-DDUCKDB_EXTENSION_API_VERSION_MAJOR=${MINIMUM_DUCKDB_VERSION_MAJOR})
 add_definitions(-DDUCKDB_EXTENSION_API_VERSION_MINOR=${MINIMUM_DUCKDB_VERSION_MINOR})
 add_definitions(-DDUCKDB_EXTENSION_API_VERSION_PATCH=${MINIMUM_DUCKDB_VERSION_PATCH})
 add_definitions(-DDUCKDB_EXTENSION_NAME=${EXTENSION_NAME})
 
+###
+# Build
+###
+project(${EXTENSION_NAME})
+
 set(EXTENSION_SOURCES
     src/add_numbers.cpp
     src/capi_quack.cpp
 )
 
 add_library(${EXTENSION_NAME} SHARED ${EXTENSION_SOURCES})
-target_include_directories(${EXTENSION_NAME} PRIVATE src/include)
+target_include_directories(${EXTENSION_NAME} PRIVATE src/include)
+target_include_directories(${EXTENSION_NAME} PRIVATE duckdb_capi)

Makefile

@@ -2,45 +2,18 @@
 
 PROJ_DIR := $(dir $(abspath $(lastword $(MAKEFILE_LIST))))
 
+# Main extension configuration
 EXTENSION_NAME=capi_quack
 MINIMUM_DUCKDB_VERSION_MAJOR=0
 MINIMUM_DUCKDB_VERSION_MINOR=0
 MINIMUM_DUCKDB_VERSION_PATCH=1
-
 MINIMUM_DUCKDB_VERSION=v$(MINIMUM_DUCKDB_VERSION_MAJOR).$(MINIMUM_DUCKDB_VERSION_MINOR).$(MINIMUM_DUCKDB_VERSION_PATCH)
 
-CMAKE_VERSION_PARAMS = -DEXTENSION_NAME=$(EXTENSION_NAME)
-CMAKE_VERSION_PARAMS += -DMINIMUM_DUCKDB_VERSION_MAJOR=$(MINIMUM_DUCKDB_VERSION_MAJOR)
-CMAKE_VERSION_PARAMS += -DMINIMUM_DUCKDB_VERSION_MINOR=$(MINIMUM_DUCKDB_VERSION_MINOR)
-CMAKE_VERSION_PARAMS += -DMINIMUM_DUCKDB_VERSION_PATCH=$(MINIMUM_DUCKDB_VERSION_PATCH)
-
 all: configure debug
 
 # Include makefiles from DuckDB
 include extension-ci-tools/makefiles/duckdb_extension_c_api.Makefile
-
-############################################### TODO MOVE TO MAKEFILE ###############################################
-
-build_extension_library_debug: check_configure
-	mkdir -p ./cmake_build/debug && \
-    	cd cmake_build/debug && \
-    	cmake $(CMAKE_VERSION_PARAMS) -DCMAKE_BUILD_TYPE=Debug ../.. && \
-      	cmake --build . --config Debug
-	$(PYTHON_VENV_BIN) -c "from pathlib import Path;Path('./build/debug/extension/$(EXTENSION_NAME)').mkdir(parents=True, exist_ok=True)"
-	$(PYTHON_VENV_BIN) -c "import shutil;shutil.copyfile('cmake_build/debug/$(EXTENSION_LIB_FILENAME)', 'build/debug/$(EXTENSION_LIB_FILENAME)')"
-
-build_extension_library_release: check_configure
-	mkdir -p ./cmake_build/release && \
-    	cd cmake_build/release && \
-    	cmake $(CMAKE_VERSION_PARAMS) -DCMAKE_BUILD_TYPE=Release ../.. && \
-    	cmake --build . --config Release
-	$(PYTHON_VENV_BIN) -c "from pathlib import Path;Path('./build/release/extension/$(EXTENSION_NAME)').mkdir(parents=True, exist_ok=True)"
-	$(PYTHON_VENV_BIN) -c "import shutil;shutil.copyfile('cmake_build/release/$(EXTENSION_LIB_FILENAME)', 'build/release/$(EXTENSION_LIB_FILENAME)')"
-
-clean_c:
-	rm -rf cmake_build
-
-###############################################
+include ./duckdb_extension_c.Makefile
 
 configure: venv platform extension_version
 
@@ -51,5 +24,5 @@ test: test_debug
 test_debug: test_extension_debug
 test_release: test_extension_release
 
-clean: clean_build clean_c
+clean: clean_build clean_cmake
 clean_all: clean_configure clean

README.md

@@ -0,0 +1,91 @@
+# DuckDB C/C++ extension template
+This is an **experimental** template for C or C++ based extensions based on the C Extension API of DuckDB. Note that this
+is a different template from 
+
+Features:
+- No DuckDB build required
+- CI/CD chain preconfigured
+- (Coming soon) Works with community extensions
+
+## Cloning
+Clone the repo with submodules
+
+```shell
+git clone --recurse-submodules <repo>
+```
+
+## Dependencies
+In principle, compiling this template only requires a C/C++ toolchain. However, this template relies on some additional
+tooling to make life a little easier and to be able to share CI/CD infrastructure with extension templates for other languages:
+
+- Python3
+- Python3-venv
+- [Make](https://www.gnu.org/software/make)
+- CMake
+- Git
+
+Installing these dependencies will vary per platform:
+- For Linux, these come generally pre-installed or are available through the distro-specific package manager.
+- For MacOS, [homebrew](https://formulae.brew.sh/).
+- For Windows, [chocolatey](https://community.chocolatey.org/).
+
+## Building
+After installing the dependencies, building is a two-step process. Firstly run:
+```shell
+make configure
+```
+This will ensure a Python venv is set up with DuckDB and DuckDB's test runner installed. Additionally, depending on configuration,
+DuckDB will be used to determine the correct platform for which you are compiling.
+
+Then, to build the extension run:
+```shell
+make debug
+```
+This delegates the build process to cargo, which will produce a shared library in `target/debug/<shared_lib_name>`. After this step, 
+a script is run to transform the shared library into a loadable extension by appending a binary footer. The resulting extension is written
+to the `build/debug` directory.
+
+To create optimized release binaries, simply run `make release` instead.
+
+## Testing
+This extension uses the DuckDB Python client for testing. This should be automatically installed in the `make configure` step.
+The tests themselves are written in the SQLLogicTest format, just like most of DuckDB's tests. A sample test can be found in
+`test/sql/<extension_name>.test`. To run the tests using the *debug* build:
+
+```shell
+make test_debug
+```
+
+or for the *release* build:
+```shell
+make test_release
+```
+
+### Version switching 
+Testing with different DuckDB versions is really simple:
+
+First, run 
+```
+make clean_all
+```
+to ensure the previous `make configure` step is deleted.
+
+Then, run 
+```
+DUCKDB_TEST_VERSION=v1.1.2 make configure
+```
+to select a different duckdb version to test with
+
+Finally, build and test with 
+```
+make debug
+make test_debug
+```
+
+### Known issues
+This is a bit of a footgun, but the extensions produced by this template may (or may not) be broken on windows on python3.11 
+with the following error on extension load:
+```shell
+IO Error: Extension '<name>.duckdb_extension' could not be loaded: The specified module could not be found
+```
+This was resolved by using python 3.12

duckdb_capi/README.md

@@ -0,0 +1,13 @@
+# DuckDB C API Headers
+This directory contains the C API headers of DuckDB. These headers should be of the same 
+DuckDB version as is specified in `Makefile`. Note that these headers can be updated automatically 
+to match the `MINIMUM_DUCKDB_VERSION` makefile variable by running (assuming the default makefile setup):
+
+```shell
+make update_duckdb_headers
+```
+
+Of course manually updating the headers is also fine, just make sure that the headers are always from the same 
+DuckDB version and that they are not from a later release of DuckDB than is specified in the `MINIMUM_DUCKDB_VERSION`
+build variable. Using headers from an older version than `MINIMUM_DUCKDB_VERSION` is allowed, but you probably don't want
+that.

src/include/duckdb.h → duckdb_capi/duckdb.h

@@ -2258,6 +2258,23 @@ Creates a value representing a NULL value.
 */
 DUCKDB_API duckdb_value duckdb_create_null_value();
 
+/*!
+Returns the number of elements in a LIST value.
+
+* @param value The LIST value.
+* @return The number of elements in the list.
+*/
+DUCKDB_API idx_t duckdb_get_list_size(duckdb_value value);
+
+/*!
+Returns the LIST child at index as a duckdb_value.
+
+* @param value The LIST value.
+* @param index The index of the child.
+* @return The child as a duckdb_value.
+*/
+DUCKDB_API duckdb_value duckdb_get_list_child(duckdb_value value, idx_t index);
+
 //===--------------------------------------------------------------------===//
 // Logical Type Interface
 //===--------------------------------------------------------------------===//

src/include/duckdb_extension.h → duckdb_capi/duckdb_extension.h

@@ -498,6 +498,8 @@ typedef struct {
 	duckdb_logical_type (*duckdb_param_logical_type)(duckdb_prepared_statement prepared_statement, idx_t param_idx);
 	bool (*duckdb_is_null_value)(duckdb_value value);
 	duckdb_value (*duckdb_create_null_value)();
+	idx_t (*duckdb_get_list_size)(duckdb_value value);
+	duckdb_value (*duckdb_get_list_child)(duckdb_value value, idx_t index);
 #endif
 
 } duckdb_ext_api_v0;
@@ -883,6 +885,8 @@ typedef struct {
 #define duckdb_param_logical_type                duckdb_ext_api.duckdb_param_logical_type
 #define duckdb_is_null_value                     duckdb_ext_api.duckdb_is_null_value
 #define duckdb_create_null_value                 duckdb_ext_api.duckdb_create_null_value
+#define duckdb_get_list_size                     duckdb_ext_api.duckdb_get_list_size
+#define duckdb_get_list_child                    duckdb_ext_api.duckdb_get_list_child
 #define duckdb_appender_create_ext               duckdb_ext_api.duckdb_appender_create_ext
 #define duckdb_table_description_create_ext      duckdb_ext_api.duckdb_table_description_create_ext
 #define duckdb_table_description_get_column_name duckdb_ext_api.duckdb_table_description_get_column_name

duckdb_extension_c.Makefile

@@ -0,0 +1,52 @@
+# Reusable makefile for the C/C++ extensions targeting the C extension API
+#
+# Inputs
+#   EXTENSION_NAME               : name of the extension (lower case)
+#   EXTENSION_LIB_FILENAME       : the library name that is produced by the build
+#	MINIMUM_DUCKDB_VERSION       : full version tag (including v)
+#	MINIMUM_DUCKDB_VERSION_MAJOR : major version
+#	MINIMUM_DUCKDB_VERSION_MINOR : minor version
+#	MINIMUM_DUCKDB_VERSION_PATCH : patch version
+#	CMAKE_EXTRA_BUILD_FLAGS      : additional CMake flags to pass
+
+
+.PHONY: build_extension_library_debug build_extension_library_release update_duckdb_headers
+
+# Create build params to pass name and version
+CMAKE_VERSION_PARAMS = -DEXTENSION_NAME=$(EXTENSION_NAME)
+CMAKE_VERSION_PARAMS += -DMINIMUM_DUCKDB_VERSION=$(MINIMUM_DUCKDB_VERSION_MAJOR)
+CMAKE_VERSION_PARAMS += -DMINIMUM_DUCKDB_VERSION_MINOR=$(MINIMUM_DUCKDB_VERSION_MINOR)
+CMAKE_VERSION_PARAMS += -DMINIMUM_DUCKDB_VERSION_PATCH=$(MINIMUM_DUCKDB_VERSION_PATCH)
+
+CMAKE_BUILD_FLAGS = $(CMAKE_VERSION_PARAMS) $(CMAKE_EXTRA_BUILD_FLAGS)
+
+#############################################
+### Rust Build targets
+#############################################
+
+build_extension_library_debug: check_configure
+	cmake $(CMAKE_BUILD_FLAGS) -DCMAKE_BUILD_TYPE=Debug -S $(PROJ_DIR) -B cmake_build/debug
+	cmake --build cmake_build/debug --config Debug
+	$(PYTHON_VENV_BIN) -c "from pathlib import Path;Path('./build/debug/extension/$(EXTENSION_NAME)').mkdir(parents=True, exist_ok=True)"
+	$(PYTHON_VENV_BIN) -c "import shutil;shutil.copyfile('cmake_build/debug/$(EXTENSION_LIB_FILENAME)', 'build/debug/$(EXTENSION_LIB_FILENAME)')"
+
+build_extension_library_release: check_configure
+	cmake $(CMAKE_BUILD_FLAGS) -DCMAKE_BUILD_TYPE=Release -S $(PROJ_DIR) -B cmake_build/release
+	cmake --build cmake_build/release --config Release
+	$(PYTHON_VENV_BIN) -c "from pathlib import Path;Path('./build/release/extension/$(EXTENSION_NAME)').mkdir(parents=True, exist_ok=True)"
+	$(PYTHON_VENV_BIN) -c "import shutil;shutil.copyfile('cmake_build/release/$(EXTENSION_LIB_FILENAME)', 'build/release/$(EXTENSION_LIB_FILENAME)')"
+
+#############################################
+### Misc
+#############################################
+# TODO: switch this to use the $(MINIMUM_DUCKDB_VERSION) after v1.2.0 is released
+BASE_HEADER_URL=https://raw.githubusercontent.com/duckdb/duckdb/refs/heads/main/src/include
+DUCKDB_C_HEADER_URL=$(BASE_HEADER_URL)/duckdb.h
+DUCKDB_C_EXTENSION_HEADER_URL=$(BASE_HEADER_URL)/duckdb_extension.h
+
+update_duckdb_headers:
+	$(PYTHON_VENV_BIN) -c "import urllib.request;urllib.request.urlretrieve('$(DUCKDB_C_HEADER_URL)', 'duckdb_capi/duckdb.h')"
+	$(PYTHON_VENV_BIN) -c "import urllib.request;urllib.request.urlretrieve('$(DUCKDB_C_EXTENSION_HEADER_URL)', 'duckdb_capi/duckdb_extension.h')"
+
+clean_cmake:
+	rm -rf cmake_build

src/add_numbers.cpp

@@ -34,7 +34,7 @@ static void AddNumbersTogether(duckdb_function_info info, duckdb_data_chunk inpu
 	} else {
 		// no NULL values - iterate and do the operation directly
 		for (idx_t row = 0; row < input_size; row++) {
-			result_data[row] = a_data[row] + b_data[row];
+			result_data[row] = a_data[row] * b_data[row];
 		}
 	}
 }
@@ -43,7 +43,7 @@ static void AddNumbersTogether(duckdb_function_info info, duckdb_data_chunk inpu
 void RegisterAddNumbersFunction(duckdb_connection connection) {
 	// create a scalar function
 	auto function = duckdb_create_scalar_function();
-	duckdb_scalar_function_set_name(function, "add_numbers_together");
+	duckdb_scalar_function_set_name(function, "multiply_numbers_together");
 
 	// add a two bigint parameters
 	duckdb_logical_type type = duckdb_create_logical_type(DUCKDB_TYPE_BIGINT);

test/sql/capi_quack.test

@@ -1,20 +1,18 @@
 # name: test/sql/capi_quack.test
 # description: test capi_quack extension
-# group: [quack]
+# group: [capi_quack]
 
 # Before we load the extension, this will fail
 statement error
-SELECT capi_quack('Sam');
+SELECT multiply_numbers_together(1,2);
 ----
-Catalog Error: Scalar Function with name capi_quack does not exist!
+Catalog Error: Scalar Function with name multiply_numbers_together does not exist!
 
 # Require statement will ensure the extension is loaded from now on
 require capi_quack
 
-require icu
-
 # Confirm the extension works
 query I
-SELECT * from capi_quack('Sam');
+SELECT multiply_numbers_together(5,10)
 ----
-Capi Quack Sam 🐥
+50