esp-idf/tools/ci/check_public_headers.py

#!/usr/bin/env python
#
# Checks all public headers in IDF in the ci
#
# SPDX-FileCopyrightText: 2020-2022 Espressif Systems (Shanghai) CO LTD
# SPDX-License-Identifier: Apache-2.0
#

from __future__ import print_function, unicode_literals

import argparse
import fnmatch
import json
import os
import queue
import re
import subprocess
import tempfile
from io import open
from threading import Event, Thread
from typing import List, Optional, Set, Tuple, Union


class HeaderFailed(Exception):
    """Base header failure exeption"""
    pass


class HeaderFailedSdkconfig(HeaderFailed):
    def __str__(self) -> str:
        return 'Sdkconfig Error'


class HeaderFailedBuildError(HeaderFailed):
    def __str__(self) -> str:
        return 'Header Build Error'


class HeaderFailedCppGuardMissing(HeaderFailed):
    def __str__(self) -> str:
        return 'Header Missing C++ Guard'


class HeaderFailedContainsCode(HeaderFailed):
    def __str__(self) -> str:
        return 'Header Produced non-zero object'


class HeaderFailedContainsStaticAssert(HeaderFailed):
    def __str__(self) -> str:
        return 'Header uses _Static_assert or static_assert instead of ESP_STATIC_ASSERT'


#   Creates a temp file and returns both output as a string and a file name
#
def exec_cmd_to_temp_file(what: List, suffix: str='') -> Tuple[int, str, str, str, str]:
    out_file = tempfile.NamedTemporaryFile(suffix=suffix, delete=False)
    rc, out, err, cmd = exec_cmd(what, out_file)
    with open(out_file.name, 'r', encoding='utf-8') as f:
        out = f.read()
    return rc, out, err, out_file.name, cmd


def exec_cmd(what: List, out_file: Union['tempfile._TemporaryFileWrapper[bytes]', int]=subprocess.PIPE) -> Tuple[int, str, str, str]:
    p = subprocess.Popen(what, stdin=subprocess.PIPE, stdout=out_file, stderr=subprocess.PIPE)
    output_b, err_b = p.communicate()
    rc = p.returncode
    output: str = output_b.decode('utf-8') if output_b is not None else ''
    err: str = err_b.decode('utf-8') if err_b is not None else ''
    return rc, output, err, ' '.join(what)


class PublicHeaderChecker:
    # Intermediate results
    COMPILE_ERR_REF_CONFIG_HDR_FAILED = 1  # -> Cannot compile and failed with injected SDKCONFIG #error (header FAILs)
    COMPILE_ERR_ERROR_MACRO_HDR_OK = 2     # -> Cannot compile, but failed with "#error" directive (header seems OK)
    COMPILE_ERR_HDR_FAILED = 3             # -> Cannot compile with another issue, logged if verbose (header FAILs)
    PREPROC_OUT_ZERO_HDR_OK = 4            # -> Both preprocessors produce zero out (header file is OK)
    PREPROC_OUT_SAME_HRD_FAILED = 5        # -> Both preprocessors produce the same, non-zero output (header file FAILs)
    PREPROC_OUT_DIFFERENT_WITH_EXT_C_HDR_OK = 6    # -> Both preprocessors produce different, non-zero output with extern "C" (header seems OK)
    PREPROC_OUT_DIFFERENT_NO_EXT_C_HDR_FAILED = 7  # -> Both preprocessors produce different, non-zero output without extern "C" (header fails)
    HEADER_CONTAINS_STATIC_ASSERT = 8      # -> Header file contains _Static_assert instead of static_assert or ESP_STATIC_ASSERT

    def log(self, message: str, debug: bool=False) -> None:
        if self.verbose or debug:
            print(message)

    def __init__(self, verbose: bool=False, jobs: int=1, prefix: Optional[str]=None) -> None:
        self.gcc = '{}gcc'.format(prefix)
        self.gpp = '{}g++'.format(prefix)
        self.verbose = verbose
        self.jobs = jobs
        self.prefix = prefix
        self.extern_c = re.compile(r'extern "C"')
        self.error_macro = re.compile(r'#error')
        self.error_orphan_kconfig = re.compile(r'#error CONFIG_VARS_USED_WHILE_SDKCONFIG_NOT_INCLUDED')
        self.kconfig_macro = re.compile(r'\bCONFIG_[A-Z0-9_]+')
        self.static_assert = re.compile(r'(_Static_assert|static_assert)')
        self.defines_assert = re.compile(r'#define[ \t]+ESP_STATIC_ASSERT')
        self.auto_soc_header = re.compile(r'components/soc/esp[a-z0-9_]+/include(?:/rev[0-9]+)?/(soc|modem)/[a-zA-Z0-9_]+.h')
        self.assembly_nocode = r'^\s*(\.file|\.text|\.ident|\.option|\.attribute).*$'
        self.check_threads: List[Thread] = []

        self.job_queue: queue.Queue = queue.Queue()
        self.failed_queue: queue.Queue = queue.Queue()
        self.terminate = Event()

    def __enter__(self) -> 'PublicHeaderChecker':
        for i in range(self.jobs):
            t = Thread(target=self.check_headers, args=(i, ))
            self.check_threads.append(t)
            t.start()
        return self

    def __exit__(self, exc_type: str, exc_value: str, traceback: str) -> None:
        self.terminate.set()
        for t in self.check_threads:
            t.join()

    # thread function process incoming header file from a queue
    def check_headers(self, num: int) -> None:
        while not self.terminate.is_set():
            if not self.job_queue.empty():
                task = self.job_queue.get()
                if task is None:
                    self.terminate.set()
                else:
                    try:
                        self.check_one_header(task, num)
                    except HeaderFailed as e:
                        self.failed_queue.put('{}: Failed! {}'.format(task, e))
                    except Exception as e:
                        # Makes sure any unexpected exceptions causes the program to terminate
                        self.failed_queue.put('{}: Failed! {}'.format(task, e))
                        self.terminate.set()
                        raise

    def get_failed(self) -> List:
        return list(self.failed_queue.queue)

    def join(self) -> None:
        for t in self.check_threads:
            while t.is_alive() and not self.terminate.is_set():
                t.join(1)  # joins with timeout to respond to keyboard interrupt

    # Checks one header calling:
    # - preprocess_one_header() to test and compare preprocessor outputs
    # - check_no_code() to test if header contains some executable code
    # Procedure
    # 1) Preprocess the include file with C preprocessor and with CPP preprocessor
    #   - Pass the test if the preprocessor outputs are the same and whitespaces only (#define only header)
    #   - Fail the test if the preprocessor outputs are the same (but with some code)
    #   - If outputs different, continue with 2)
    # 2) Strip out all include directives to generate "temp.h"
    # 3) Preprocess the temp.h the same way in (1)
    #   - Pass the test if the preprocessor outputs are the same and whitespaces only (#include only header)
    #   - Fail the test if the preprocessor outputs are the same (but with some code)
    #   - If outputs different, pass the test
    # 4) If header passed the steps 1) and 3) test that it produced zero assembly code
    def check_one_header(self, header: str, num: int) -> None:
        res = self.preprocess_one_header(header, num)
        if res == self.COMPILE_ERR_REF_CONFIG_HDR_FAILED:
            raise HeaderFailedSdkconfig()
        elif res == self.COMPILE_ERR_ERROR_MACRO_HDR_OK:
            return self.compile_one_header(header)
        elif res == self.COMPILE_ERR_HDR_FAILED:
            raise HeaderFailedBuildError()
        elif res == self.PREPROC_OUT_ZERO_HDR_OK:
            return self.compile_one_header(header)
        elif res == self.PREPROC_OUT_SAME_HRD_FAILED:
            raise HeaderFailedCppGuardMissing()
        elif res == self.HEADER_CONTAINS_STATIC_ASSERT:
            raise HeaderFailedContainsStaticAssert()
        else:
            self.compile_one_header(header)
            temp_header = None
            try:
                _, _, _, temp_header, _ = exec_cmd_to_temp_file(['sed', '/#include/d; /#error/d', header], suffix='.h')
                res = self.preprocess_one_header(temp_header, num, ignore_sdkconfig_issue=True)
                if res == self.PREPROC_OUT_SAME_HRD_FAILED:
                    raise HeaderFailedCppGuardMissing()
                elif res == self.PREPROC_OUT_DIFFERENT_NO_EXT_C_HDR_FAILED:
                    raise HeaderFailedCppGuardMissing()
            finally:
                if temp_header:
                    os.unlink(temp_header)

    def compile_one_header(self, header: str) -> None:
        rc, out, err, cmd = exec_cmd([self.gcc, '-S', '-o-', '-include', header, self.main_c] + self.include_dir_flags)
        if rc == 0:
            if not re.sub(self.assembly_nocode, '', out, flags=re.M).isspace():
                raise HeaderFailedContainsCode()
            return  # Header OK: produced zero code
        self.log('{}: FAILED: compilation issue'.format(header), True)
        self.log(err, True)
        self.log('\nCompilation command failed:\n{}\n'.format(cmd), True)
        raise HeaderFailedBuildError()

    def preprocess_one_header(self, header: str, num: int, ignore_sdkconfig_issue: bool=False) -> int:
        all_compilation_flags = ['-w', '-P', '-E', '-DESP_PLATFORM', '-include', header, self.main_c] + self.include_dir_flags
        # just strip comments to check for CONFIG_... macros or static asserts
        rc, out, err, _ = exec_cmd([self.gcc, '-fpreprocessed', '-dD',  '-P',  '-E', header] + self.include_dir_flags)
        if not ignore_sdkconfig_issue:
            if re.search(self.kconfig_macro, out):
                # enable defined #error if sdkconfig.h not included
                all_compilation_flags.append('-DIDF_CHECK_SDKCONFIG_INCLUDED')
        # If the file contain _Static_assert or static_assert, make sure it does't not define ESP_STATIC_ASSERT and that it
        # is not an automatically generated soc header file
        grp = re.search(self.static_assert, out)
        # Normalize the potential A//B, A/./B, A/../A, from the name
        normalized_path = os.path.normpath(header)
        if grp and not re.search(self.defines_assert, out) and not re.search(self.auto_soc_header, normalized_path):
            self.log('{}: FAILED: contains {}. Please use ESP_STATIC_ASSERT'.format(header, grp.group(1)), True)
            return self.HEADER_CONTAINS_STATIC_ASSERT
        try:
            # compile with C++, check for errors, outputs for a temp file
            rc, cpp_out, err, cpp_out_file, cmd = exec_cmd_to_temp_file([self.gpp, '--std=c++17'] + all_compilation_flags)
            if rc != 0:
                if re.search(self.error_macro, err):
                    if re.search(self.error_orphan_kconfig, err):
                        self.log('{}: CONFIG_VARS_USED_WHILE_SDKCONFIG_NOT_INCLUDED'.format(header), True)
                        return self.COMPILE_ERR_REF_CONFIG_HDR_FAILED
                    self.log('{}: Error directive failure: OK'.format(header))
                    return self.COMPILE_ERR_ERROR_MACRO_HDR_OK
                self.log('{}: FAILED: compilation issue'.format(header), True)
                self.log(err, True)
                self.log('\nCompilation command failed:\n{}\n'.format(cmd), True)
                return self.COMPILE_ERR_HDR_FAILED
            # compile with C compiler, outputs to another temp file
            rc, _, err, c99_out_file, _ = exec_cmd_to_temp_file([self.gcc, '--std=c99'] + all_compilation_flags)
            if rc != 0:
                self.log('{} FAILED should never happen'.format(header))
                return self.COMPILE_ERR_HDR_FAILED
            # diff the two outputs
            rc, diff, err, _ = exec_cmd(['diff', c99_out_file, cpp_out_file])
            if not diff or diff.isspace():
                if not cpp_out or cpp_out.isspace():
                    self.log('{} The same, but empty out - OK'.format(header))
                    return self.PREPROC_OUT_ZERO_HDR_OK
                self.log('{} FAILED C and C++ preprocessor output is the same!'.format(header), True)
                return self.PREPROC_OUT_SAME_HRD_FAILED
            if re.search(self.extern_c, diff):
                self.log('{} extern C present - OK'.format(header))
                return self.PREPROC_OUT_DIFFERENT_WITH_EXT_C_HDR_OK
            self.log('{} Different but no extern C - FAILED'.format(header), True)
            return self.PREPROC_OUT_DIFFERENT_NO_EXT_C_HDR_FAILED
        finally:
            os.unlink(cpp_out_file)
            try:
                os.unlink(c99_out_file)
            except Exception:
                pass

    # Get compilation data from an example to list all public header files
    def list_public_headers(self, ignore_dirs: List, ignore_files: Union[List, Set], only_dir: str=None) -> None:
        idf_path = os.getenv('IDF_PATH')
        if idf_path is None:
            raise RuntimeError("Environment variable 'IDF_PATH' wasn't set.")
        project_dir = os.path.join(idf_path, 'examples', 'get-started', 'blink')
        build_dir = tempfile.mkdtemp()
        sdkconfig = os.path.join(build_dir, 'sdkconfig')
        try:
            os.unlink(os.path.join(project_dir, 'sdkconfig'))
        except FileNotFoundError:
            pass
        subprocess.check_call(['idf.py', '-B', build_dir, f'-DSDKCONFIG={sdkconfig}', 'reconfigure'], cwd=project_dir)
        build_commands_json = os.path.join(build_dir, 'compile_commands.json')
        with open(build_commands_json, 'r', encoding='utf-8') as f:
            build_command = json.load(f)[0]['command'].split()
        include_dir_flags = []
        include_dirs = []
        # process compilation flags (includes and defines)
        for item in build_command:
            if item.startswith('-I'):
                include_dir_flags.append(item)
                if 'components' in item:
                    include_dirs.append(item[2:])  # Removing the leading "-I"
            if item.startswith('-D'):
                include_dir_flags.append(item.replace('\\',''))  # removes escaped quotes, eg: -DMBEDTLS_CONFIG_FILE=\\\"mbedtls/esp_config.h\\\"
        include_dir_flags.append('-I' + os.path.join(build_dir, 'config'))
        include_dir_flags.append('-DCI_HEADER_CHECK')
        sdkconfig_h = os.path.join(build_dir, 'config', 'sdkconfig.h')
        # prepares a main_c file for easier sdkconfig checks and avoid compilers warning when compiling headers directly
        with open(sdkconfig_h, 'a') as f:
            f.write('#define IDF_SDKCONFIG_INCLUDED')
        main_c = os.path.join(build_dir, 'compile.c')
        with open(main_c, 'w') as f:
            f.write('#if defined(IDF_CHECK_SDKCONFIG_INCLUDED) && ! defined(IDF_SDKCONFIG_INCLUDED)\n'
                    '#error CONFIG_VARS_USED_WHILE_SDKCONFIG_NOT_INCLUDED\n'
                    '#endif')
        # processes public include dirs, removing ignored files
        all_include_files = []
        files_to_check = []
        for d in include_dirs:
            if only_dir is not None and not os.path.relpath(d, idf_path).startswith(only_dir):
                self.log('{} - directory ignored (not in "{}")'.format(d, only_dir))
                continue
            if os.path.relpath(d, idf_path).startswith(tuple(ignore_dirs)):
                self.log('{} - directory ignored'.format(d))
                continue
            for root, dirnames, filenames in os.walk(d):
                for filename in fnmatch.filter(filenames, '*.h'):
                    all_include_files.append(os.path.join(root, filename))
        self.main_c = main_c
        self.include_dir_flags = include_dir_flags
        ignore_files = set(ignore_files)
        # processes public include files, removing ignored files
        for file_name in all_include_files:
            rel_path_file = os.path.relpath(file_name, idf_path)
            if any([os.path.commonprefix([d, rel_path_file]) == d for d in ignore_dirs]):
                self.log('{} - file ignored (inside ignore dir)'.format(file_name))
                continue
            if rel_path_file in ignore_files:
                self.log('{} - file ignored'.format(file_name))
                continue
            files_to_check.append(file_name)
        # removes duplicates and places headers to a work queue
        for file_name in set(files_to_check):
            self.job_queue.put(file_name)
        self.job_queue.put(None)  # to indicate the last job


def check_all_headers() -> None:
    parser = argparse.ArgumentParser('Public header checker file', formatter_class=argparse.RawDescriptionHelpFormatter, epilog='''\
    Tips for fixing failures reported by this script
    ------------------------------------------------
    This checker validates all public headers to detect these types of issues:
    1) "Sdkconfig Error": Using SDK config macros without including "sdkconfig.h"
        * Check if the failing include file or any other included file uses "CONFIG_..." prefixed macros
    2) "Header Build Error": Header itself is not compilable (missing includes, macros, types)
        * Check that all referenced macros, types are available (defined or included)
        * Check that all included header files are available (included in paths)
        * Check for possible compilation issues
        * Try to compile only the offending header file
    3) "Header Missing C++ Guard": Preprocessing the header by C and C++ should produce different output
        * Check if the "#ifdef __cplusplus" header sentinels are present
    4) "Header Produced non-zero object": Header contains some object, a definition
        * Check if no definition is present in the offending header file
    5) "Header contains _Static_assert or static_assert": Makes the use of _Static_assert or static_assert
        functions instead of using ESP_STATIC_ASSERT macro

    Notes:
    * The script validates *all* header files (recursively) in public folders for all components.
    * The script locates include paths from running a default build of  "examples/get-started/blink'
    * The script does not support any other targets than esp32

    General tips:
    * Use "-d" argument to make the script check only the offending header file
    * Use "-v" argument to produce more verbose output
    * Copy, paste and execute the compilation commands to reproduce build errors (script prints out
      the entire compilation command line with absolute paths)
    ''')
    parser.add_argument('--verbose', '-v', help='enables verbose mode', action='store_true')
    parser.add_argument('--jobs', '-j', help='number of jobs to run checker', default=1, type=int)
    parser.add_argument('--prefix', '-p', help='compiler prefix', default='xtensa-esp32-elf-', type=str)
    parser.add_argument('--exclude-file', '-e', help='exception file', default='check_public_headers_exceptions.txt', type=str)
    parser.add_argument('--only-dir', '-d', help='reduce the analysis to this directory only', default=None, type=str)
    args = parser.parse_args()

    # process excluded files and dirs
    exclude_file = os.path.join(os.path.dirname(__file__), args.exclude_file)
    with open(exclude_file, 'r', encoding='utf-8') as f:
        lines = [line.rstrip() for line in f]
    ignore_files = []
    ignore_dirs = []
    for line in lines:
        if not line or line.isspace() or line.startswith('#'):
            continue
        if os.path.isdir(line):
            ignore_dirs.append(line)
        else:
            ignore_files.append(line)

    # start header check
    with PublicHeaderChecker(args.verbose, args.jobs, args.prefix) as header_check:
        header_check.list_public_headers(ignore_dirs, ignore_files, only_dir=args.only_dir)
        try:
            header_check.join()
            failures = header_check.get_failed()
            if len(failures) > 0:
                for failed in failures:
                    print(failed)
                print(parser.epilog)
                exit(1)
            print('No errors found')
        except KeyboardInterrupt:
            print('Keyboard interrupt')


if __name__ == '__main__':
    check_all_headers()