filemerge: show warning about choice of :prompt only at an actual fallback
Before this patch, internal merge tool :prompt shows "no tool found to
merge FILE" line, even if :prompt is explicitly specified as a tool to
be used.
This patch shows warning message about choice of :prompt only at an
actual fallback, in which case any tool is rejected by capability for
binary or symlink.
It is for backward compatibility to omit warning message in
"changedelete" case.
# Copyright (c) 2016-present, Gregory Szorc
# All rights reserved.
#
# This software may be modified and distributed under the terms
# of the BSD license. See the LICENSE file for details.
from __future__ import absolute_import
import cffi
import distutils.ccompiler
import os
import re
import subprocess
import tempfile
HERE = os.path.abspath(os.path.dirname(__file__))
SOURCES = ['zstd/%s' % p for p in (
'common/entropy_common.c',
'common/error_private.c',
'common/fse_decompress.c',
'common/pool.c',
'common/threading.c',
'common/xxhash.c',
'common/zstd_common.c',
'compress/fse_compress.c',
'compress/huf_compress.c',
'compress/zstd_compress.c',
'compress/zstdmt_compress.c',
'decompress/huf_decompress.c',
'decompress/zstd_decompress.c',
'dictBuilder/cover.c',
'dictBuilder/divsufsort.c',
'dictBuilder/zdict.c',
)]
# Headers whose preprocessed output will be fed into cdef().
HEADERS = [os.path.join(HERE, 'zstd', *p) for p in (
('zstd.h',),
('compress', 'zstdmt_compress.h'),
('dictBuilder', 'zdict.h'),
)]
INCLUDE_DIRS = [os.path.join(HERE, d) for d in (
'zstd',
'zstd/common',
'zstd/compress',
'zstd/decompress',
'zstd/dictBuilder',
)]
# cffi can't parse some of the primitives in zstd.h. So we invoke the
# preprocessor and feed its output into cffi.
compiler = distutils.ccompiler.new_compiler()
# Needed for MSVC.
if hasattr(compiler, 'initialize'):
compiler.initialize()
# Distutils doesn't set compiler.preprocessor, so invoke the preprocessor
# manually.
if compiler.compiler_type == 'unix':
args = list(compiler.executables['compiler'])
args.extend([
'-E',
'-DZSTD_STATIC_LINKING_ONLY',
'-DZDICT_STATIC_LINKING_ONLY',
])
elif compiler.compiler_type == 'msvc':
args = [compiler.cc]
args.extend([
'/EP',
'/DZSTD_STATIC_LINKING_ONLY',
'/DZDICT_STATIC_LINKING_ONLY',
])
else:
raise Exception('unsupported compiler type: %s' % compiler.compiler_type)
def preprocess(path):
with open(path, 'rb') as fh:
lines = []
for l in fh:
# zstd.h includes <stddef.h>, which is also included by cffi's
# boilerplate. This can lead to duplicate declarations. So we strip
# this include from the preprocessor invocation.
#
# The same things happens for including zstd.h, so give it the same
# treatment.
#
# We define ZSTD_STATIC_LINKING_ONLY, which is redundant with the inline
# #define in zstdmt_compress.h and results in a compiler warning. So drop
# the inline #define.
if l.startswith((b'#include <stddef.h>',
b'#include "zstd.h"',
b'#define ZSTD_STATIC_LINKING_ONLY')):
continue
# ZSTDLIB_API may not be defined if we dropped zstd.h. It isn't
# important so just filter it out.
if l.startswith(b'ZSTDLIB_API'):
l = l[len(b'ZSTDLIB_API '):]
lines.append(l)
fd, input_file = tempfile.mkstemp(suffix='.h')
os.write(fd, b''.join(lines))
os.close(fd)
try:
process = subprocess.Popen(args + [input_file], stdout=subprocess.PIPE)
output = process.communicate()[0]
ret = process.poll()
if ret:
raise Exception('preprocessor exited with error')
return output
finally:
os.unlink(input_file)
def normalize_output(output):
lines = []
for line in output.splitlines():
# CFFI's parser doesn't like __attribute__ on UNIX compilers.
if line.startswith(b'__attribute__ ((visibility ("default"))) '):
line = line[len(b'__attribute__ ((visibility ("default"))) '):]
if line.startswith(b'__attribute__((deprecated('):
continue
elif b'__declspec(deprecated(' in line:
continue
lines.append(line)
return b'\n'.join(lines)
ffi = cffi.FFI()
# *_DISABLE_DEPRECATE_WARNINGS prevents the compiler from emitting a warning
# when cffi uses the function. Since we statically link against zstd, even
# if we use the deprecated functions it shouldn't be a huge problem.
ffi.set_source('_zstd_cffi', '''
#include "mem.h"
#define ZSTD_STATIC_LINKING_ONLY
#include "zstd.h"
#define ZDICT_STATIC_LINKING_ONLY
#define ZDICT_DISABLE_DEPRECATE_WARNINGS
#include "zdict.h"
#include "zstdmt_compress.h"
''', sources=SOURCES, include_dirs=INCLUDE_DIRS)
DEFINE = re.compile(b'^\\#define ([a-zA-Z0-9_]+) ')
sources = []
# Feed normalized preprocessor output for headers into the cdef parser.
for header in HEADERS:
preprocessed = preprocess(header)
sources.append(normalize_output(preprocessed))
# #define's are effectively erased as part of going through preprocessor.
# So perform a manual pass to re-add those to the cdef source.
with open(header, 'rb') as fh:
for line in fh:
line = line.strip()
m = DEFINE.match(line)
if not m:
continue
if m.group(1) == b'ZSTD_STATIC_LINKING_ONLY':
continue
# The parser doesn't like some constants with complex values.
if m.group(1) in (b'ZSTD_LIB_VERSION', b'ZSTD_VERSION_STRING'):
continue
# The ... is magic syntax by the cdef parser to resolve the
# value at compile time.
sources.append(m.group(0) + b' ...')
cdeflines = b'\n'.join(sources).splitlines()
cdeflines = [l for l in cdeflines if l.strip()]
ffi.cdef(b'\n'.join(cdeflines).decode('latin1'))
if __name__ == '__main__':
ffi.compile()