esp-idf/tools/cmake/convert_to_cmake.py

#!/usr/bin/env python
#
# Command line tool to convert simple ESP-IDF Makefile & component.mk files to
# CMakeLists.txt files
#
import argparse
import subprocess
import re
import os.path
import glob
import sys

debug = False

def get_make_variables(path, makefile="Makefile", expected_failure=False, variables={}):
    """
    Given the path to a Makefile of some kind, return a dictionary of all variables defined in this Makefile

    Uses 'make' to parse the Makefile syntax, so we don't have to!

    Overrides IDF_PATH= to avoid recursively evaluating the entire project Makefile structure.
    """
    variable_setters = [ ("%s=%s" % (k,v)) for (k,v) in variables.items() ]

    cmdline = ["make", "-rpn", "-C", path, "-f", makefile ] + variable_setters
    if debug:
        print("Running %s..." % (" ".join(cmdline)))

    p = subprocess.Popen(cmdline, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
    (output, stderr) = p.communicate("\n")

    if (not expected_failure) and p.returncode != 0:
        raise RuntimeError("Unexpected make failure, result %d" % p.returncode)

    if debug:
        print("Make stdout:")
        print(output)
        print("Make stderr:")
        print(stderr)

    next_is_makefile = False  # is the next line a makefile variable?
    result = {}
    BUILT_IN_VARS = set(["MAKEFILE_LIST", "SHELL", "CURDIR", "MAKEFLAGS"])

    for line in output.decode().split("\n"):
        if line.startswith("# makefile"):  # this line appears before any variable defined in the makefile itself
            next_is_makefile = True
        elif next_is_makefile:
            next_is_makefile = False
            m = re.match(r"(?P<var>[^ ]+) :?= (?P<val>.+)", line)
            if m is not None:
                if not m.group("var") in BUILT_IN_VARS:
                    result[m.group("var")] = m.group("val").strip()

    return result

def get_component_variables(project_path, component_path):
    make_vars = get_make_variables(component_path,
                                   os.path.join(os.environ["IDF_PATH"],
                                                "make",
                                                "component_wrapper.mk"),
                                   expected_failure=True,
                                   variables = {
                                       "COMPONENT_MAKEFILE" : os.path.join(component_path, "component.mk"),
                                       "COMPONENT_NAME" : os.path.basename(component_path),
                                       "PROJECT_PATH": project_path,
                                   })

    if "COMPONENT_OBJS" in make_vars:  # component.mk specifies list of object files
        # Convert to sources
        def find_src(obj):
            obj = os.path.splitext(obj)[0]
            for ext in [ "c", "cpp", "S" ]:
                if os.path.exists(os.path.join(component_path, obj) + "." + ext):
                    return obj + "." + ext
            print("WARNING: Can't find source file for component %s COMPONENT_OBJS %s" % (component_path, obj))
            return None

        srcs = []
        for obj in make_vars["COMPONENT_OBJS"].split(" "):
            src = find_src(obj)
            if src is not None:
                srcs.append(src)
        make_vars["COMPONENT_SRCS"] = " ".join(srcs)
    else:  # Use COMPONENT_SRCDIRS
        make_vars["COMPONENT_SRCDIRS"] = make_vars.get("COMPONENT_SRCDIRS", ".")

    make_vars["COMPONENT_ADD_INCLUDEDIRS"] = make_vars.get("COMPONENT_ADD_INCLUDEDIRS", "include")

    return make_vars


def convert_project(project_path):
    if not os.path.exists(project_path):
        raise RuntimeError("Project directory '%s' not found" % project_path)
    if not os.path.exists(os.path.join(project_path, "Makefile")):
        raise RuntimeError("Directory '%s' doesn't contain a project Makefile" % project_path)

    project_cmakelists = os.path.join(project_path, "CMakeLists.txt")
    if os.path.exists(project_cmakelists):
        raise RuntimeError("This project already has a CMakeLists.txt file")

    project_vars = get_make_variables(project_path, expected_failure=True)
    if not "PROJECT_NAME" in project_vars:
        raise RuntimeError("PROJECT_NAME does not appear to be defined in IDF project Makefile at %s" % project_path)

    component_paths = project_vars["COMPONENT_PATHS"].split(" ")

    # "main" component is made special in cmake, so extract it from the component_paths list
    try:
        main_component_path = [ p for p in component_paths if os.path.basename(p) == "main" ][0]
        if debug:
            print("Found main component %s"  % main_component_path)
        main_vars = get_component_variables(project_path, main_component_path)
    except IndexError:
        print("WARNING: Project has no 'main' component, but CMake-based system requires at least one file in MAIN_SRCS...")
        main_vars = { "COMPONENT_SRCS" : ""} # dummy for MAIN_SRCS

    # Remove main component from list of components we're converting to cmake
    component_paths = [ p for p in component_paths if os.path.basename(p) != "main" ]

    # Convert components as needed
    for p in component_paths:
        convert_component(project_path, p)

    # Look up project variables before we start writing the file, so nothing
    # is created if there is an error

    main_srcs = main_vars["COMPONENT_SRCS"].split(" ")
    # convert from component-relative to absolute paths
    main_srcs = [ os.path.normpath(os.path.join(main_component_path, m)) for m in main_srcs ]
    # convert to make relative to the project directory
    main_srcs = [ os.path.relpath(m, project_path) for m in main_srcs ]

    project_name = project_vars["PROJECT_NAME"]

    # Generate the project CMakeLists.txt file
    with open(project_cmakelists, "w") as f:
        f.write("""
# (Automatically converted from project Makefile by convert_to_cmake.py.)

# The following four lines of boilerplate have to be in your project's CMakeLists
# in this exact order for cmake to work correctly
cmake_minimum_required(VERSION 3.5)

""")
        f.write("set(MAIN_SRCS %s)\n" % " ".join(main_srcs))
        f.write("""
include($ENV{IDF_PATH}/tools/cmake/project.cmake)
""")
        f.write("project(%s)\n" % project_name)

    print("Converted project %s" % project_cmakelists)

def convert_component(project_path, component_path):
    if debug:
        print("Converting %s..." % (component_path))
    cmakelists_path = os.path.join(component_path, "CMakeLists.txt")
    if os.path.exists(cmakelists_path):
        print("Skipping already-converted component %s..." % cmakelists_path)
        return
    v = get_component_variables(project_path, component_path)

    # Look up all the variables before we start writing the file, so it's not
    # created if there's an erro
    component_srcs = v.get("COMPONENT_SRCS", None)
    component_srcdirs = None
    if component_srcs is not None:
        # see if we should be using COMPONENT_SRCS or COMPONENT_SRCDIRS, if COMPONENT_SRCS is everything in SRCDIRS
        component_allsrcs = []
        for d in v.get("COMPONENT_SRCDIRS", "").split(" "):
            component_allsrcs += glob.glob(os.path.normpath(os.path.join(component_path, d, "*.[cS]")))
            component_allsrcs += glob.glob(os.path.normpath(os.path.join(component_path, d, "*.cpp")))
        abs_component_srcs = [os.path.normpath(os.path.join(component_path, p)) for p in component_srcs.split(" ")]
        if set(component_allsrcs) == set(abs_component_srcs):
            component_srcdirs = v.get("COMPONENT_SRCDIRS")

    component_add_includedirs = v["COMPONENT_ADD_INCLUDEDIRS"]
    cflags = v.get("CFLAGS", None)

    with open(cmakelists_path, "w") as f:
        f.write("set(COMPONENT_ADD_INCLUDEDIRS %s)\n\n" % component_add_includedirs)
        if component_srcdirs is not None:
            f.write("set(COMPONENT_SRCDIRS %s)\n\n" % component_srcdirs)
            f.write("register_component()\n")
        elif component_srcs is not None:
            f.write("set(COMPONENT_SRCS %s)\n\n" % component_srcs)
            f.write("register_component()\n")
        else:
            f.write("register_config_only_component()\n")
        if cflags is not None:
            f.write("component_compile_options(%s)\n" % cflags)

    print("Converted %s" % cmakelists_path)


def main():
    global debug

    parser = argparse.ArgumentParser(description='convert_to_cmake.py - ESP-IDF Project Makefile to CMakeLists.txt converter', prog='convert_to_cmake')

    parser.add_argument('--debug', help='Display debugging output',
                        action='store_true')

    parser.add_argument('project', help='Path to project to convert (defaults to CWD)', default=os.getcwd(), metavar='project path', nargs='?')

    args = parser.parse_args()
    debug = args.debug
    print("Converting %s..." % args.project)
    convert_project(args.project)


if __name__ == "__main__":
    main()