vmod: Add vmod_math code generator

Author: nigoroll

.gitignore

@@ -81,6 +81,8 @@ cscope.*out
 /vmod/vcc_*_if.h
 /vmod/vmod_*.rst
 /vmod/vmod_vcs_version.txt
+/vmod/vmod_math.vcc
+/vmod/vmod_math.c
 
 # Man-files and binaries
 /man/*.1

vmod/Makefile.am

@@ -33,6 +33,7 @@ include $(srcdir)/automake_boilerplate_h2.am
 include $(srcdir)/automake_boilerplate_cookie.am
 include $(srcdir)/automake_boilerplate_debug.am
 include $(srcdir)/automake_boilerplate_directors.am
+include $(srcdir)/automake_boilerplate_math.am
 include $(srcdir)/automake_boilerplate_proxy.am
 include $(srcdir)/automake_boilerplate_purge.am
 include $(srcdir)/automake_boilerplate_std.am
@@ -55,3 +56,14 @@ vmod_debug_symbols_regex = 'Vmod_.*_Data'
 
 # not --strict, not installed
 vmodtoolargs_debug = --boilerplate --noinst -o vcc_debug_if
+
+### vmod_math specific
+# the specs are deliberately checked in to not make the build
+# dependend on external connectivity
+vmod_math_spec.html:
+	curl -o $@ https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/math.h.html
+
+vmod_math.c: vmod_math.vcc
+
+vmod_math.vcc: vmod_math_spec.html vmod_math_gen.py
+	@PYTHON@ vmod_math_gen.py $< vmod_math.vcc vmod_math.c

vmod/automake_boilerplate_math.am

@@ -0,0 +1,40 @@
+## Generated by vmodtool.py --boilerplate.
+
+vmod_LTLIBRARIES += libvmod_math.la
+dist_vcc_DATA += $(srcdir)/vmod_math.vcc
+
+libvmod_math_la_SOURCES = \
+	vmod_math.c
+
+libvmod_math_la_CFLAGS =
+
+vmodtoolargs_math ?= --strict --boilerplate -o vcc_math_if
+vmod_math_symbols_regex ?= Vmod_math_Data
+
+libvmod_math_la_LDFLAGS = \
+	-export-symbols-regex $(vmod_math_symbols_regex) \
+	$(AM_LDFLAGS) \
+	$(VMOD_LDFLAGS) \
+	-rpath $(vmoddir)
+
+nodist_libvmod_math_la_SOURCES = vcc_math_if.c vcc_math_if.h
+
+EXTRA_libvmod_math_la_DEPENDENCIES = $(nodist_libvmod_math_la_SOURCES)
+
+EXTRA_DIST += automake_boilerplate_math.am
+
+$(libvmod_math_la_OBJECTS): vcc_math_if.h
+
+vcc_math_if.h vmod_math.rst vmod_math.man.rst: vcc_math_if.c
+
+# A doc-change will not update mtime on the .h and .c files, so a
+# touch(1) is necessary to signal that vmodtool was in fact run.
+vcc_math_if.c: $(VMODTOOL) $(srcdir)/vmod_math.vcc
+	@PYTHON@ $(VMODTOOL) $(vmodtoolargs_math) $(srcdir)/vmod_math.vcc
+	touch vcc_math_if.c
+
+clean-local: clean-vmod-math
+
+clean-vmod-math:
+	rm -f $(nodist_libvmod_math_la_SOURCES)
+	rm -f vmod_math.rst vmod_math.man.rst

vmod/vmod_math_gen.py

@@ -0,0 +1,219 @@
+#!/usr/bin/env python3
+
+# Copyright 2025 UPLEX - Nils Goroll Systemoptimierung
+# All rights reserved.
+#
+# Author: Nils Goroll <nils.goroll@uplex.de>
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+#
+# generate vmod_math vcc and c files from opengroup spec html
+
+import re
+import sys
+
+
+vcc_type_map = {
+    "int": "INT",
+    "double": "REAL",
+    "long": "INT",
+    "real-floating": "REAL",
+    "const char *": "STRING",
+}
+
+def_arg_names = ["x", "y", "z"]
+arg_names_map = {
+    "atan2": ["y", "x"],
+    "ldexp": ["x", "exp"],
+    "nan": ["tag"],
+    "scalbln": ["x", "exp"],
+    "yn": ["n", "x"],
+}
+
+# type name
+re_arg = re.compile(r"^(.+?)(\s+[xy])?$")
+# argument separator
+re_argsep = re.compile(r",\s*")
+
+
+def vcc_arg(arg, n):
+    match = re_arg.search(arg)
+    if match is None:
+        print(f"Error: no re_arg match on '{arg}'")
+        sys.exit(1)
+    # print(match)
+
+    atype = vcc_type_map[match.group(1)]
+    name = match.group(2)
+
+    if name is None:
+        name = n
+
+    return f"{atype} {name}"
+
+
+def gen_func_vcc(match, vcc_fh):
+    rtype = match.group(1)
+    name = match.group(2)
+    args = match.group(3)
+
+    # print(match)
+
+    rtype = vcc_type_map[rtype]
+    args = re_argsep.split(args)
+
+    argnames = def_arg_names[: len(args)]
+    if name in arg_names_map:
+        argnames = arg_names_map[name]
+
+    args = ", ".join([vcc_arg(arg, name) for arg, name in zip(args, argnames)])
+
+    tpl = f"""
+$Function {rtype} {name}({args})
+"""
+
+    vcc_fh.write(tpl)
+
+
+def c_arg(arg, n):
+    match = re_arg.search(arg)
+    if match is None:
+        print(f"Error: no re_arg match on '{arg}'")
+        sys.exit(1)
+    # print(match)
+
+    atype = "VCL_" + vcc_type_map[match.group(1)]
+    name = match.group(2)
+
+    if name is None:
+        name = n
+
+    return f"{atype} {name}"
+
+
+def gen_func_c(match, c_fh):
+    rtype = match.group(1)
+    name = match.group(2)
+    args = match.group(3)
+
+    # print(match)
+
+    rtype = "VCL_" + vcc_type_map[rtype]
+    args = re_argsep.split(args)
+
+    argnames = def_arg_names[: len(args)]
+    if name in arg_names_map:
+        argnames = arg_names_map[name]
+
+    args = ", ".join([c_arg(arg, name) for arg, name in zip(args, argnames)])
+    argnames = ", ".join(argnames)
+
+    tpl = f"""
+{rtype}
+vmod_{name}(VRT_CTX, {args})
+{{
+	(void)ctx;
+	return ({name}({argnames}));
+}}
+"""
+
+    c_fh.write(tpl)
+
+
+def gen_func(func, vcc_fh, c_fh):
+    gen_func_vcc(func, vcc_fh)
+    gen_func_c(func, c_fh)
+
+
+# rtype name (args...)
+re_spec_funcs = re.compile(r"\b([a-z0-9 ]+?)\s+([a-z0-9]+)\((.*)\)(?=;)")
+# disregard variants for types we do not need or can not support
+# not support: frexp(double, int *) etc returning two values
+re_func_disregard = re.compile(r"long double|float|long long|int \*|double \*")
+
+
+def gen_funcs(spec, vcc_fh, c_fh):
+    for match in re_spec_funcs.finditer(spec):
+        f = match.group(0)
+        #print("XXX " + match.group(0))
+        if re_func_disregard.search(f):
+            #print(f"disregard: {f}")
+            continue
+        gen_func(match, vcc_fh, c_fh)
+
+
+vcc_top = '''
+# this code is auto-generated. Do not edit
+$ABI vrt
+$Module math 3 "VMOD wrapping math.h"
+
+DESCRIPTION
+===========
+
+This VMOD wraps the functions in math.h.
+
+For documentation, see ``man <function>``.
+
+'''
+
+c_top = '''
+/* this code is auto-generated. Do not edit */
+#include "config.h"
+
+#include <math.h>
+
+#include "vdef.h"
+#include "vrt.h"
+#include "vcc_math_if.h"
+'''
+
+def main():
+    # Check command line arguments
+    if len(sys.argv) != 4:
+        print("Usage: python3 script.py <spec_file> <vcc_file> <c_file>")
+        sys.exit(1)
+
+    spec_file = sys.argv[1]
+    vcc_file = sys.argv[2]
+    c_file = sys.argv[3]
+
+    spec = ""
+
+    try:
+        with open(spec_file, "r") as f:
+            spec = f.read()
+    except FileNotFoundError:
+        print(f"Error: Input file '{spec_file}' not found")
+        sys.exit(1)
+
+    with open(vcc_file, "w") as vcc_fh:
+        vcc_fh.write(vcc_top)
+        with open(c_file, "w") as c_fh:
+            c_fh.write(c_top)
+            gen_funcs(spec, vcc_fh, c_fh)
+    print(f"Output written to '{vcc_file}' and '{c_file}'")
+
+
+if __name__ == "__main__":
+    main()