1 files changed, 173 insertions, 0 deletions
diff --git a/Tools/c-analyzer/c_parser/preprocessor/common.py b/Tools/c-analyzer/c_parser/preprocessor/common.py
new file mode 100644
index 0000000..6368102
--- /dev/null
+++ b/Tools/c-analyzer/c_parser/preprocessor/common.py
@@ -0,0 +1,173 @@
+import contextlib
+import distutils.ccompiler
+import logging
+import shlex
+import subprocess
+import sys
+
+from ..info import FileInfo, SourceLine
+from .errors import (
+    PreprocessorFailure,
+    ErrorDirectiveError,
+    MissingDependenciesError,
+    OSMismatchError,
+)
+
+
+logger = logging.getLogger(__name__)
+
+
+# XXX Add aggregate "source" class(es)?
+#  * expose all lines as single text string
+#  * expose all lines as sequence
+#  * iterate all lines
+
+
+def run_cmd(argv, *,
+            #capture_output=True,
+            stdout=subprocess.PIPE,
+            #stderr=subprocess.STDOUT,
+            stderr=subprocess.PIPE,
+            text=True,
+            check=True,
+            **kwargs
+            ):
+    if isinstance(stderr, str) and stderr.lower() == 'stdout':
+        stderr = subprocess.STDOUT
+
+    kw = dict(locals())
+    kw.pop('argv')
+    kw.pop('kwargs')
+    kwargs.update(kw)
+
+    proc = subprocess.run(argv, **kwargs)
+    return proc.stdout
+
+
+def preprocess(tool, filename, **kwargs):
+    argv = _build_argv(tool, filename, **kwargs)
+    logger.debug(' '.join(shlex.quote(v) for v in argv))
+
+    # Make sure the OS is supported for this file.
+    if (_expected := is_os_mismatch(filename)):
+        error = None
+        raise OSMismatchError(filename, _expected, argv, error, TOOL)
+
+    # Run the command.
+    with converted_error(tool, argv, filename):
+        # We use subprocess directly here, instead of calling the
+        # distutil compiler object's preprocess() method, since that
+        # one writes to stdout/stderr and it's simpler to do it directly
+        # through subprocess.
+        return run_cmd(argv)
+
+
+def _build_argv(
+    tool,
+    filename,
+    incldirs=None,
+    macros=None,
+    preargs=None,
+    postargs=None,
+    executable=None,
+    compiler=None,
+):
+    compiler = distutils.ccompiler.new_compiler(
+        compiler=compiler or tool,
+    )
+    if executable:
+        compiler.set_executable('preprocessor', executable)
+
+    argv = None
+    def _spawn(_argv):
+        nonlocal argv
+        argv = _argv
+    compiler.spawn = _spawn
+    compiler.preprocess(
+        filename,
+        macros=[tuple(v) for v in macros or ()],
+        include_dirs=incldirs or (),
+        extra_preargs=preargs or (),
+        extra_postargs=postargs or (),
+    )
+    return argv
+
+
+@contextlib.contextmanager
+def converted_error(tool, argv, filename):
+    try:
+        yield
+    except subprocess.CalledProcessError as exc:
+        convert_error(
+            tool,
+            argv,
+            filename,
+            exc.stderr,
+            exc.returncode,
+        )
+
+
+def convert_error(tool, argv, filename, stderr, rc):
+    error = (stderr.splitlines()[0], rc)
+    if (_expected := is_os_mismatch(filename, stderr)):
+        logger.debug(stderr.strip())
+        raise OSMismatchError(filename, _expected, argv, error, tool)
+    elif (_missing := is_missing_dep(stderr)):
+        logger.debug(stderr.strip())
+        raise MissingDependenciesError(filename, (_missing,), argv, error, tool)
+    elif '#error' in stderr:
+        # XXX Ignore incompatible files.
+        error = (stderr.splitlines()[1], rc)
+        logger.debug(stderr.strip())
+        raise ErrorDirectiveError(filename, argv, error, tool)
+    else:
+        # Try one more time, with stderr written to the terminal.
+        try:
+            output = run_cmd(argv, stderr=None)
+        except subprocess.CalledProcessError:
+            raise PreprocessorFailure(filename, argv, error, tool)
+
+
+def is_os_mismatch(filename, errtext=None):
+    # See: https://docs.python.org/3/library/sys.html#sys.platform
+    actual = sys.platform
+    if actual == 'unknown':
+        raise NotImplementedError
+
+    if errtext is not None:
+        if (missing := is_missing_dep(errtext)):
+            matching = get_matching_oses(missing, filename)
+            if actual not in matching:
+                return matching
+    return False
+
+
+def get_matching_oses(missing, filename):
+    # OSX
+    if 'darwin' in filename or 'osx' in filename:
+        return ('darwin',)
+    elif missing == 'SystemConfiguration/SystemConfiguration.h':
+        return ('darwin',)
+
+    # Windows
+    elif missing in ('windows.h', 'winsock2.h'):
+        return ('win32',)
+
+    # other
+    elif missing == 'sys/ldr.h':
+        return ('aix',)
+    elif missing == 'dl.h':
+        # XXX The existence of Python/dynload_dl.c implies others...
+        # Note that hpux isn't actual supported any more.
+        return ('hpux', '???')
+
+    # unrecognized
+    else:
+        return ()
+
+
+def is_missing_dep(errtext):
+    if 'No such file or directory' in errtext:
+        missing = errtext.split(': No such file or directory')[0].split()[-1]
+        return missing
+    return False