xref: /aosp_15_r20/external/angle/build/rust/run_rs_bindings_from_cc.py (revision 8975f5c5ed3d1c378011245431ada316dfb6f244)
1#!/usr/bin/env python3
2
3# Copyright 2022 The Chromium Authors
4# Use of this source code is governed by a BSD-style license that can be
5# found in the LICENSE file.
6
7import argparse
8import json
9import os
10import subprocess
11import sys
12
13THIS_DIR = os.path.dirname(os.path.abspath(__file__))
14CHROMIUM_SRC_DIR = os.path.relpath(os.path.join(THIS_DIR, os.pardir, os.pardir))
15sys.path.append(THIS_DIR)
16from run_bindgen import filter_clang_args
17
18RUST_TOOLCHAIN_DIR = os.path.join(CHROMIUM_SRC_DIR, "third_party",
19                                  "rust-toolchain")
20RUSTFMT_EXE_PATH = os.path.join(RUST_TOOLCHAIN_DIR, "bin", "rustfmt")
21RUSTFMT_CONFIG_PATH = os.path.join(CHROMIUM_SRC_DIR, ".rustfmt.toml")
22RS_BINDINGS_FROM_CC_EXE_PATH = os.path.join(RUST_TOOLCHAIN_DIR, "bin",
23                                            "rs_bindings_from_cc")
24
25
26def format_cmdline(args):
27  def quote_arg(x):
28    if ' ' not in x: return x
29    x = x.replace('"', '\\"')
30    return f"\"{x}\""
31
32  return " ".join([quote_arg(x) for x in args])
33
34
35def main():
36  parser = argparse.ArgumentParser()
37  parser.add_argument("--targets_and_args_from_gn",
38                      metavar="FILE",
39                      help="File parsed into --targets_and_args Crubit arg",
40                      required=True),
41  parser.add_argument("--public_headers",
42                      metavar="FILE",
43                      help="Passed through to Crubit",
44                      required=True),
45  parser.add_argument("--rs_out",
46                      metavar="FILE",
47                      help="Passed through to Crubit",
48                      required=True),
49  parser.add_argument("--cc_out",
50                      metavar="FILE",
51                      help="Passed through to Crubit",
52                      required=True),
53  parser.add_argument("clang_args",
54                      metavar="CLANGARGS",
55                      help="Arguments to forward to clang libraries",
56                      nargs=argparse.REMAINDER)
57  args = parser.parse_args()
58
59  # Output paths
60  generator_args = []
61  generator_args.append("--rs_out={0}".format(os.path.relpath(args.rs_out)))
62  generator_args.append("--cc_out={0}".format(os.path.relpath(args.cc_out)))
63  if "CRUBIT_DEBUG" in os.environ:
64    generator_args.append("--ir_out={0}".format(
65        os.path.relpath(args.rs_out).replace(".rs", ".ir")))
66
67  # Public headers.
68  generator_args.append("--public_headers={0}".format(",".join(
69      [os.path.relpath(hdr) for hdr in args.public_headers.split(",")])))
70
71  # Targets to headers map.
72  with open(args.targets_and_args_from_gn, "r") as f:
73    targets_and_args = json.load(f)
74  for entry in targets_and_args:
75    entry["f"] = ["supported"]
76    hdrs = entry["h"]
77    for i in range(len(hdrs)):
78      hdrs[i] = os.path.relpath(hdrs[i])
79  generator_args.append("--targets_and_args={0}".format(
80      json.dumps(targets_and_args)))
81
82  # All Crubit invocations in Chromium share the following cmdline args.
83  generator_args.append(f"--rustfmt_exe_path={RUSTFMT_EXE_PATH}")
84  generator_args.append(f"--rustfmt_config_path={RUSTFMT_CONFIG_PATH}")
85  generator_args.append(
86      "--crubit_support_path=third_party/crubit/src/rs_bindings_from_cc/support"
87  )
88
89  # Long cmdlines may not work - work around that by using Abseil's `--flagfile`
90  # https://abseil.io/docs/python/guides/flags#a-note-about---flagfile
91  #
92  # Note that `clang_args` are not written to the flag file, because Abseil's
93  # flag parsing code is only aware of `ABSL_FLAG`-declared flags and doesn't
94  # know about Clang args (e.g. `-W...` or `-I...`).
95  params_file_path = os.path.relpath(args.rs_out).replace(".rs", ".params")
96  with open(params_file_path, "w") as f:
97    for line in generator_args:
98      print(line, file=f)
99
100  # Clang arguments.
101  #
102  # The call to `filter_clang_args` is needed to avoid the following error:
103  # error: unable to find plugin 'find-bad-constructs'
104  clang_args = []
105  clang_args.extend(filter_clang_args(args.clang_args))
106  # TODO(crbug.com/40226863): This warning needs to be suppressed, because
107  # otherwise Crubit/Clang complains as follows:
108  #     error: .../third_party/rust-toolchain/bin/rs_bindings_from_cc:
109  #     'linker' input unused [-Werror,-Wunused-command-line-argument]
110  # Maybe `build/rust/rs_bindings_from_cc.gni` gives too much in `args`?  But
111  # then `{{cflags}}` seems perfectly reasonable...
112  clang_args += ["-Wno-unused-command-line-argument"]
113
114  # Print a copy&pastable final cmdline when asked for debugging help.
115  cmdline = [RS_BINDINGS_FROM_CC_EXE_PATH, f"--flagfile={params_file_path}"]
116  cmdline.extend(clang_args)
117  if "CRUBIT_DEBUG" in os.environ:
118    pretty_cmdline = format_cmdline(cmdline)
119    print(f"CRUBIT_DEBUG: CMDLINE: {pretty_cmdline}", file=sys.stderr)
120
121  # TODO(crbug.com/40226863): run_bindgen.py removes the outputs when the tool
122  # fails.  Maybe we need to do something similar here?  OTOH in most failure
123  # modes Crubit will fail *before* generating its outputs...
124  return subprocess.run(cmdline).returncode
125
126
127if __name__ == '__main__':
128  sys.exit(main())
129