build: add recipes for installing fftpack

deps/checksums/pffft_1_1_0_tar_gz/sha256

@@ -0,0 +1 @@
+ea0701a6bc256405b03975908a6a92d0ffecdd18579e8484b8d789c8bd561787

deps/test/fftpack/test_install.c

@@ -0,0 +1,36 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2026 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+
+extern void rffti( int n, double *wsave );
+
+int main( void ) {
+	double wsave[ 2*8 + 15 ]; // 2*n + 15
+	int n = 8;
+	int i;
+
+	rffti( n, wsave );
+
+	printf( "rffti( %d, wsave )\n", n );
+	for ( i = n; i < 2*n; i++ ) {
+		printf( "wsave[%2d] = %f\n", i, wsave[i] );
+	}
+	printf( "\n" );
+}

tools/make/common.mk

@@ -688,3 +688,14 @@ DEPS_CPPCHECK_BUILD_OUT ?= $(DEPS_BUILD_DIR)/cppcheck_$(deps_cppcheck_version_sl
 
 # Host platform:
 DEPS_CPPCHECK_PLATFORM := $(shell command -v $(NODE) >/dev/null 2>&1 && $(NODE_HOST_PLATFORM))
+
+# FFTPACK...
+
+# Define the PFFFT version:
+DEPS_FFTPACK_VERSION ?= 1.1.0
+
+# Generate a version slug:
+deps_fftpack_version_slug := $(subst .,_,$(DEPS_FFTPACK_VERSION))
+
+# Define the output path when building FFTPACK:
+DEPS_FFTPACK_BUILD_OUT ?= $(DEPS_BUILD_DIR)/pffft-$(DEPS_FFTPACK_VERSION)

tools/make/lib/install/Makefile

@@ -39,6 +39,7 @@ include $(TOOLS_MAKE_LIB_DIR)/install/cephes.mk
 include $(TOOLS_MAKE_LIB_DIR)/install/cppcheck.mk
 include $(TOOLS_MAKE_LIB_DIR)/install/electron.mk
 include $(TOOLS_MAKE_LIB_DIR)/install/emsdk.mk
+include $(TOOLS_MAKE_LIB_DIR)/install/fftpack.mk
 include $(TOOLS_MAKE_LIB_DIR)/install/llvm.mk
 include $(TOOLS_MAKE_LIB_DIR)/install/node.mk
 include $(TOOLS_MAKE_LIB_DIR)/install/openblas.mk
@@ -157,7 +158,7 @@ clean-deps-tests: clean-deps-openblas-tests
 # @example
 # make install-deps-dev
 #/
-install-deps-dev: install-deps-boost install-deps-cephes install-deps-cppcheck install-deps-python install-deps-r install-deps-shellcheck
+install-deps-dev: install-deps-boost install-deps-cephes install-deps-cppcheck install-deps-fftpack install-deps-python install-deps-r install-deps-shellcheck
 
 .PHONY: install-deps-dev
 
@@ -167,7 +168,7 @@ install-deps-dev: install-deps-boost install-deps-cephes install-deps-cppcheck i
 # @example
 # make clean-deps-dev
 #/
-clean-deps-dev: clean-deps-boost clean-deps-cephes clean-deps-cppcheck clean-deps-python clean-deps-r clean-deps-shellcheck
+clean-deps-dev: clean-deps-boost clean-deps-cephes clean-deps-cppcheck clean-deps-fftpack clean-deps-python clean-deps-r clean-deps-shellcheck
 
 .PHONY: clean-deps-dev
 
@@ -177,7 +178,7 @@ clean-deps-dev: clean-deps-boost clean-deps-cephes clean-deps-cppcheck clean-dep
 # @example
 # make clean-deps-dev-tests
 #/
-clean-deps-dev-tests: clean-deps-boost-tests clean-deps-cephes-tests clean-deps-cppcheck-tests clean-deps-shellcheck-tests
+clean-deps-dev-tests: clean-deps-boost-tests clean-deps-cephes-tests clean-deps-cppcheck-tests clean-deps-fftpack-tests clean-deps-shellcheck-tests
 
 .PHONY: clean-deps-dev-tests
 

tools/make/lib/install/fftpack.mk

@@ -0,0 +1,177 @@
+#/
+# @license Apache-2.0
+#
+# Copyright (c) 2026 The Stdlib Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#    http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#/
+
+# VARIABLES #
+
+# Define the download URL:
+DEPS_FFTPACK_URL ?= https://github.com/marton78/pffft/archive/refs/tags/v$(DEPS_FFTPACK_VERSION).tar.gz
+
+# Determine the basename for the download:
+deps_fftpack_basename := pffft-$(DEPS_FFTPACK_VERSION).tar.gz
+
+# Define the path to the file containing a checksum to verify a download:
+DEPS_FFTPACK_CHECKSUM ?= $(shell $(CAT) $(DEPS_CHECKSUMS_DIR)/$(subst .,_,$(subst -,_,$(deps_fftpack_basename)))/sha256)
+
+# Define the output path when downloading:
+DEPS_FFTPACK_DOWNLOAD_OUT ?= $(DEPS_TMP_DIR)/$(deps_fftpack_basename)
+
+# Define a list of source files:
+deps_fftpack_src := \
+	src/fftpack.c
+
+# Resolve a list of source files to absolute filepaths:
+DEPS_FFTPACK_SRC ?= $(addprefix $(DEPS_FFTPACK_BUILD_OUT)/,$(deps_fftpack_src))
+
+# Define the path to the directory containing tests:
+DEPS_FFTPACK_TEST_DIR ?= $(DEPS_DIR)/test/fftpack
+
+# Define the output directory path for compiled tests:
+DEPS_FFTPACK_TEST_OUT ?= $(DEPS_FFTPACK_TEST_DIR)/build
+
+# Define the path to a test file for checking an installation:
+DEPS_FFTPACK_TEST_INSTALL ?= $(DEPS_FFTPACK_TEST_DIR)/test_install.c
+
+# Define the output path for a test file:
+DEPS_FFTPACK_TEST_INSTALL_OUT ?= $(DEPS_FFTPACK_TEST_OUT)/test_install
+
+
+# RULES #
+
+#/
+# Downloads an FFTPACK distribution.
+#
+# @private
+#/
+$(DEPS_FFTPACK_DOWNLOAD_OUT): | $(DEPS_TMP_DIR)
+	$(QUIET) echo 'Downloading FFTPACK...' >&2
+	$(QUIET) $(DEPS_DOWNLOAD_BIN) $(DEPS_FFTPACK_URL) $(DEPS_FFTPACK_DOWNLOAD_OUT)
+
+#/
+# Extracts an FFTPACK gzipped tar archive.
+#
+# @private
+#/
+$(DEPS_FFTPACK_BUILD_OUT): $(DEPS_FFTPACK_DOWNLOAD_OUT) | $(DEPS_BUILD_DIR)
+	$(QUIET) echo 'Extracting FFTPACK...' >&2
+	$(QUIET) $(TAR) -zxf $(DEPS_FFTPACK_DOWNLOAD_OUT) -C $(DEPS_BUILD_DIR)
+
+#/
+# Creates a directory for storing compiled tests.
+#
+# @private
+#/
+$(DEPS_FFTPACK_TEST_OUT):
+	$(QUIET) $(MKDIR_RECURSIVE) $(DEPS_FFTPACK_TEST_OUT)
+
+#/
+# Compiles a test file for testing an FFTPACK installation.
+#
+# @private
+#/
+$(DEPS_FFTPACK_TEST_INSTALL_OUT): $(DEPS_FFTPACK_BUILD_OUT) $(DEPS_FFTPACK_TEST_OUT)
+	$(QUIET) $(CC) -I $(DEPS_FFTPACK_BUILD_OUT) $(DEPS_FFTPACK_TEST_INSTALL) $(DEPS_FFTPACK_SRC) -o $(DEPS_FFTPACK_TEST_INSTALL_OUT)
+
+#/
+# Downloads an FFTPACK distribution.
+#
+# @private
+#
+# @example
+# make deps-download-fftpack
+#/
+deps-download-fftpack: $(DEPS_FFTPACK_DOWNLOAD_OUT)
+
+.PHONY: deps-download-fftpack
+
+#/
+# Verifies a downloaded FFTPACK distribution.
+#
+# @private
+#
+# @example
+# make deps-verify-fftpack
+#/
+deps-verify-fftpack: deps-download-fftpack
+	$(QUIET) echo 'Verifying download...' >&2
+	$(QUIET) $(DEPS_CHECKSUM_BIN) $(DEPS_FFTPACK_DOWNLOAD_OUT) $(DEPS_FFTPACK_CHECKSUM) >&2
+
+.PHONY: deps-verify-fftpack
+
+#/
+# Extracts a downloaded FFTPACK distribution.
+#
+# @private
+#
+# @example
+# make deps-extract-fftpack
+#/
+deps-extract-fftpack: $(DEPS_FFTPACK_BUILD_OUT)
+
+.PHONY: deps-extract-fftpack
+
+#/
+# Tests an installed FFTPACK distribution.
+#
+# @private
+#
+# @example
+# make deps-test-fftpack
+#/
+deps-test-fftpack: $(DEPS_FFTPACK_TEST_INSTALL_OUT)
+	$(QUIET) echo 'Running tests...' >&2
+	$(QUIET) $(DEPS_FFTPACK_TEST_INSTALL_OUT)
+	$(QUIET) echo '' >&2
+	$(QUIET) echo 'Success.' >&2
+
+.PHONY: deps-test-fftpack
+
+#/
+# Installs FFTPACK.
+#
+# @example
+# make install-deps-fftpack
+#/
+install-deps-fftpack: deps-download-fftpack deps-verify-fftpack deps-extract-fftpack deps-test-fftpack
+
+.PHONY: install-deps-fftpack
+
+#/
+# Removes an installed FFTPACK distribution.
+#
+# ## Notes
+#
+# -   The rule does **not** remove an FFTPACK download (if one exists).
+#
+# @example
+# make clean-deps-fftpack
+#/
+clean-deps-fftpack: clean-deps-fftpack-tests
+	$(QUIET) $(DELETE) $(DELETE_FLAGS) $(DEPS_FFTPACK_BUILD_OUT)
+
+.PHONY: clean-deps-fftpack
+
+#/
+# Removes compiled FFTPACK installation tests.
+#
+# @example
+# make clean-deps-fftpack-tests
+#/
+clean-deps-fftpack-tests:
+	$(QUIET) $(DELETE) $(DELETE_FLAGS) $(DEPS_FFTPACK_TEST_OUT)
+
+.PHONY: clean-deps-fftpack-tests

tools/make/lib/test-fixtures/c.mk

@@ -28,7 +28,7 @@ test-fixtures-c:
 		echo "Generating test fixtures: $$file"; \
 		cd `dirname $$file` && \
 		$(MAKE) clean && \
-		CEPHES="$(DEPS_CEPHES_BUILD_OUT)" CEPHES_SRC="$(DEPS_CEPHES_SRC)" $(MAKE) && \
+		CEPHES="$(DEPS_CEPHES_BUILD_OUT)" CEPHES_SRC="$(DEPS_CEPHES_SRC)" FFTPACK_SRC="$(DEPS_FFTPACK_SRC)" $(MAKE) && \
 		$(MAKE) run || exit 1; \
 	done
 
@@ -45,7 +45,7 @@ test-fixtures-c-files:
 		echo "Generating test fixtures: $$file"; \
 		cd `dirname $$file` && \
 		$(MAKE) clean && \
-		CEPHES="$(DEPS_CEPHES_BUILD_OUT)" CEPHES_SRC="$(DEPS_CEPHES_SRC)" $(MAKE) && \
+		CEPHES="$(DEPS_CEPHES_BUILD_OUT)" CEPHES_SRC="$(DEPS_CEPHES_SRC)" FFTPACK_SRC="$(DEPS_FFTPACK_SRC)" $(MAKE) && \
 		$(MAKE) run || exit 1; \
 	done