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-rw-r--r--build/midl.py223
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diff --git a/build/midl.py b/build/midl.py
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+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+import functools
+import os
+import shutil
+import subprocess
+import sys
+
+import buildconfig
+
+
+def relativize(path, base=None):
+ # For absolute path in Unix builds, we need relative paths because
+ # Windows programs run via Wine don't like these Unix absolute paths
+ # (they look like command line arguments).
+ if path.startswith("/"):
+ return os.path.relpath(path, base)
+ # For Windows absolute paths, we can just use the unmodified path.
+ # And if the path starts with '-', it's a command line argument.
+ if os.path.isabs(path) or path.startswith("-"):
+ return path
+ # Remaining case is relative paths, which may be relative to a different
+ # directory (os.getcwd()) than the needed `base`, so we "rebase" it.
+ return os.path.relpath(path, base)
+
+
+@functools.lru_cache(maxsize=None)
+def files_in(path):
+ return {p.lower(): os.path.join(path, p) for p in os.listdir(path)}
+
+
+def search_path(paths, path):
+ for p in paths:
+ f = os.path.join(p, path)
+ if os.path.isfile(f):
+ return f
+ # try an case-insensitive match
+ maybe_match = files_in(p).get(path.lower())
+ if maybe_match:
+ return maybe_match
+ raise RuntimeError(f"Cannot find {path}")
+
+
+# Filter-out -std= flag from the preprocessor command, as we're not preprocessing
+# C or C++, and the command would fail with the flag.
+def filter_preprocessor(cmd):
+ prev = None
+ for arg in cmd:
+ if arg == "-Xclang":
+ prev = arg
+ continue
+ if not arg.startswith("-std="):
+ if prev:
+ yield prev
+ yield arg
+ prev = None
+
+
+# Preprocess all the direct and indirect inputs of midl, and put all the
+# preprocessed inputs in the given `base` directory. Returns a tuple containing
+# the path of the main preprocessed input, and the modified flags to use instead
+# of the flags given as argument.
+def preprocess(base, input, flags):
+ import argparse
+ import re
+ from collections import deque
+
+ IMPORT_RE = re.compile('import\s*"([^"]+)";')
+
+ parser = argparse.ArgumentParser()
+ parser.add_argument("-I", action="append")
+ parser.add_argument("-D", action="append")
+ parser.add_argument("-acf")
+ args, remainder = parser.parse_known_args(flags)
+ preprocessor = (
+ list(filter_preprocessor(buildconfig.substs["CXXCPP"]))
+ # Ideally we'd use the real midl version, but querying it adds a
+ # significant overhead to configure. In practice, the version number
+ # doesn't make a difference at the moment.
+ + ["-D__midl=801"]
+ + [f"-D{d}" for d in args.D or ()]
+ + [f"-I{i}" for i in args.I or ()]
+ )
+ includes = ["."] + buildconfig.substs["INCLUDE"].split(";") + (args.I or [])
+ seen = set()
+ queue = deque([input])
+ if args.acf:
+ queue.append(args.acf)
+ output = os.path.join(base, os.path.basename(input))
+ while True:
+ try:
+ input = queue.popleft()
+ except IndexError:
+ break
+ if os.path.basename(input) in seen:
+ continue
+ seen.add(os.path.basename(input))
+ input = search_path(includes, input)
+ # If there is a .acf file corresponding to the .idl we're processing,
+ # we also want to preprocess that file because midl might look for it too.
+ if input.lower().endswith(".idl"):
+ try:
+ acf = search_path(
+ [os.path.dirname(input)], os.path.basename(input)[:-4] + ".acf"
+ )
+ if acf:
+ queue.append(acf)
+ except RuntimeError:
+ pass
+ command = preprocessor + [input]
+ preprocessed = os.path.join(base, os.path.basename(input))
+ subprocess.run(command, stdout=open(preprocessed, "wb"), check=True)
+ # Read the resulting file, and search for imports, that we'll want to
+ # preprocess as well.
+ with open(preprocessed, "r") as fh:
+ for line in fh:
+ if not line.startswith("import"):
+ continue
+ m = IMPORT_RE.match(line)
+ if not m:
+ continue
+ imp = m.group(1)
+ queue.append(imp)
+ flags = []
+ # Add -I<base> first in the flags, so that midl resolves imports to the
+ # preprocessed files we created.
+ for i in [base] + (args.I or []):
+ flags.extend(["-I", i])
+ # Add the preprocessed acf file if one was given on the command line.
+ if args.acf:
+ flags.extend(["-acf", os.path.join(base, os.path.basename(args.acf))])
+ flags.extend(remainder)
+ return output, flags
+
+
+def midl(out, input, *flags):
+ out.avoid_writing_to_file()
+ midl_flags = buildconfig.substs["MIDL_FLAGS"]
+ base = os.path.dirname(out.name) or "."
+ tmpdir = None
+ try:
+ # If the build system is asking to not use the preprocessor to midl,
+ # we need to do the preprocessing ourselves.
+ if "-no_cpp" in midl_flags:
+ # Normally, we'd use tempfile.TemporaryDirectory, but in this specific
+ # case, we actually want a deterministic directory name, because it's
+ # recorded in the code midl generates.
+ tmpdir = os.path.join(base, os.path.basename(input) + ".tmp")
+ os.makedirs(tmpdir, exist_ok=True)
+ try:
+ input, flags = preprocess(tmpdir, input, flags)
+ except subprocess.CalledProcessError as e:
+ return e.returncode
+ midl = buildconfig.substs["MIDL"]
+ wine = buildconfig.substs.get("WINE")
+ if midl.lower().endswith(".exe") and wine:
+ command = [wine, midl]
+ else:
+ command = [midl]
+ command.extend(midl_flags)
+ command.extend([relativize(f, base) for f in flags])
+ command.append("-Oicf")
+ command.append(relativize(input, base))
+ print("Executing:", " ".join(command))
+ result = subprocess.run(command, cwd=base)
+ return result.returncode
+ finally:
+ if tmpdir:
+ shutil.rmtree(tmpdir)
+
+
+# midl outputs dlldata to a single dlldata.c file by default. This prevents running
+# midl in parallel in the same directory for idl files that would generate dlldata.c
+# because of race conditions updating the file. Instead, we ask midl to create
+# separate files, and we merge them manually.
+def merge_dlldata(out, *inputs):
+ inputs = [open(i) for i in inputs]
+ read_a_line = [True] * len(inputs)
+ while True:
+ lines = [
+ f.readline() if read_a_line[n] else lines[n] for n, f in enumerate(inputs)
+ ]
+ unique_lines = set(lines)
+ if len(unique_lines) == 1:
+ # All the lines are identical
+ if not lines[0]:
+ break
+ out.write(lines[0])
+ read_a_line = [True] * len(inputs)
+ elif (
+ len(unique_lines) == 2
+ and len([l for l in unique_lines if "#define" in l]) == 1
+ ):
+ # Most lines are identical. When they aren't, it's typically because some
+ # files have an extra #define that others don't. When that happens, we
+ # print out the #define, and get a new input line from the files that had
+ # a #define on the next iteration. We expect that next line to match what
+ # the other files had on this iteration.
+ # Note: we explicitly don't support the case where there are different
+ # defines across different files, except when there's a different one
+ # for each file, in which case it's handled further below.
+ a = unique_lines.pop()
+ if "#define" in a:
+ out.write(a)
+ else:
+ out.write(unique_lines.pop())
+ read_a_line = ["#define" in l for l in lines]
+ elif len(unique_lines) != len(lines):
+ # If for some reason, we don't get lines that are entirely different
+ # from each other, we have some unexpected input.
+ print(
+ "Error while merging dlldata. Last lines read: {}".format(lines),
+ file=sys.stderr,
+ )
+ return 1
+ else:
+ for line in lines:
+ out.write(line)
+ read_a_line = [True] * len(inputs)
+
+ return 0