build/unix/rewrite_sanitizer_dylib.py

   1 # This Source Code Form is subject to the terms of the Mozilla Public
   2 # License, v. 2.0. If a copy of the MPL was not distributed with this
   3 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
   4
   5 import os
   6 import re
   7 import shutil
   8 import subprocess
   9 import sys
  10 from argparse import ArgumentParser
  11 from pathlib import Path
  12
  13 from buildconfig import substs
  14
  15 """
  16 Scans the given directories for binaries referencing the AddressSanitizer
  17 runtime library, copies it to the main directory.
  18 """
  19
  20 # This is the dylib name pattern
  21 DYLIB_NAME_PATTERN = re.compile(r"libclang_rt\.(a|ub)san_osx_dynamic\.dylib")
  22
  23
  24 def resolve_rpath(filename):
  25     otoolOut = subprocess.check_output([substs["OTOOL"], "-l", filename], text=True)
  26     currentCmd = None
  27
  28     # The lines we need to find look like this:
  29     # ...
  30     # Load command 22
  31     #           cmd LC_RPATH
  32     #       cmdsize 80
  33     #          path /home/build/src/clang/bin/../lib/clang/3.8.0/lib/darwin (offset 12)
  34     # Load command 23
  35     # ...
  36     # Other load command types have a varying number of fields.
  37     for line in otoolOut.splitlines():
  38         cmdMatch = re.match(r"^\s+cmd ([A-Z_]+)", line)
  39         if cmdMatch is not None:
  40             currentCmd = cmdMatch.group(1)
  41             continue
  42
  43         if currentCmd == "LC_RPATH":
  44             pathMatch = re.match(r"^\s+path (.*) \(offset \d+\)", line)
  45             if pathMatch is not None:
  46                 path = pathMatch.group(1)
  47                 if Path(path).is_dir():
  48                     return path
  49
  50     print(f"@rpath could not be resolved from {filename}", file=sys.stderr)
  51     sys.exit(1)
  52
  53
  54 def scan_directory(path):
  55     dylibsCopied = set()
  56     dylibsRequired = set()
  57
  58     if not path.is_dir():
  59         print(f"Input path {path} is not a folder", file=sys.stderr)
  60         sys.exit(1)
  61
  62     for file in path.rglob("*"):
  63         if not file.is_file():
  64             continue
  65
  66         # Skip all files that aren't either dylibs or executable
  67         if not (file.suffix == ".dylib" or os.access(str(file), os.X_OK)):
  68             continue
  69
  70         try:
  71             otoolOut = subprocess.check_output(
  72                 [substs["OTOOL"], "-L", str(file)], text=True
  73             )
  74         except Exception:
  75             # Errors are expected on non-mach executables, ignore them and continue
  76             continue
  77
  78         for line in otoolOut.splitlines():
  79             match = DYLIB_NAME_PATTERN.search(line)
  80
  81             if match is not None:
  82                 dylibName = match.group(0)
  83                 absDylibPath = line.split()[0]
  84
  85                 dylibsRequired.add(dylibName)
  86
  87                 if dylibName not in dylibsCopied:
  88                     if absDylibPath.startswith("@rpath/"):
  89                         rpath = resolve_rpath(str(file))
  90                         copyDylibPath = absDylibPath.replace("@rpath", rpath)
  91                     else:
  92                         copyDylibPath = absDylibPath
  93
  94                     if Path(copyDylibPath).is_file():
  95                         # Copy the runtime once to the main directory, which is passed
  96                         # as the argument to this function.
  97                         shutil.copy(copyDylibPath, str(path))
  98                         dylibsCopied.add(dylibName)
  99                     else:
 100                         print(
 101                             f"dylib path in {file} was not found at: {copyDylibPath}",
 102                             file=sys.stderr,
 103                         )
 104
 105                 break
 106
 107     dylibsMissing = dylibsRequired - dylibsCopied
 108     if dylibsMissing:
 109         for dylibName in dylibsMissing:
 110             print(f"{dylibName} could not be found", file=sys.stderr)
 111         sys.exit(1)
 112
 113
 114 def parse_args(argv=None):
 115     parser = ArgumentParser()
 116     parser.add_argument("paths", metavar="path", type=Path, nargs="+")
 117     return parser.parse_args(argv)
 118
 119
 120 if __name__ == "__main__":
 121     args = parse_args()
 122     for d in args.paths:
 123         scan_directory(d)