1 files changed, 131 insertions, 0 deletions
diff --git a/build/unix/rewrite_asan_dylib.py b/build/unix/rewrite_asan_dylib.py
new file mode 100644
index 0000000000..0bcf31b559
--- /dev/null
+++ b/build/unix/rewrite_asan_dylib.py
@@ -0,0 +1,131 @@
+# 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/.
+
+from __future__ import absolute_import, print_function, unicode_literals
+
+import re
+import sys
+import os
+import subprocess
+import shutil
+from buildconfig import substs
+
+"""
+Scans the given directories for binaries referencing the AddressSanitizer
+runtime library, copies it to the main directory and rewrites binaries to not
+reference it with absolute paths but with @executable_path instead.
+"""
+
+# This is the dylib we're looking for
+DYLIB_NAME = "libclang_rt.asan_osx_dynamic.dylib"
+
+
+def resolve_rpath(filename):
+    otoolOut = subprocess.check_output(
+        [substs["OTOOL"], "-l", filename], universal_newlines=True
+    )
+    currentCmd = None
+
+    # The lines we need to find look like this:
+    # ...
+    # Load command 22
+    #           cmd LC_RPATH
+    #       cmdsize 80
+    #          path /home/build/src/clang/bin/../lib/clang/3.8.0/lib/darwin (offset 12)
+    # Load command 23
+    # ...
+    # Other load command types have a varying number of fields.
+    for line in otoolOut.splitlines():
+        cmdMatch = re.match(r"^\s+cmd ([A-Z_]+)", line)
+        if cmdMatch is not None:
+            currentCmd = cmdMatch.group(1)
+            continue
+
+        if currentCmd == "LC_RPATH":
+            pathMatch = re.match(r"^\s+path (.*) \(offset \d+\)", line)
+            if pathMatch is not None:
+                path = pathMatch.group(1)
+                if os.path.isdir(path):
+                    return path
+
+    sys.stderr.write("@rpath could not be resolved from %s\n" % filename)
+    sys.exit(1)
+
+
+def scan_directory(path):
+    dylibCopied = False
+
+    for root, subdirs, files in os.walk(path):
+        for filename in files:
+            filename = os.path.join(root, filename)
+
+            # Skip all files that aren't either dylibs or executable
+            if not (filename.endswith(".dylib") or os.access(filename, os.X_OK)):
+                continue
+
+            try:
+                otoolOut = subprocess.check_output(
+                    [substs["OTOOL"], "-L", filename], universal_newlines=True
+                )
+            except Exception:
+                # Errors are expected on non-mach executables, ignore them and continue
+                continue
+
+            for line in otoolOut.splitlines():
+                if DYLIB_NAME in line:
+                    absDylibPath = line.split()[0]
+
+                    # Don't try to rewrite binaries twice
+                    if absDylibPath.startswith("@executable_path/"):
+                        continue
+
+                    if not dylibCopied:
+                        if absDylibPath.startswith("@rpath/"):
+                            rpath = resolve_rpath(filename)
+                            copyDylibPath = absDylibPath.replace("@rpath", rpath)
+                        else:
+                            copyDylibPath = absDylibPath
+
+                        if os.path.isfile(copyDylibPath):
+                            # Copy the runtime once to the main directory, which is passed
+                            # as the argument to this function.
+                            shutil.copy(copyDylibPath, path)
+
+                            # Now rewrite the library itself
+                            subprocess.check_call(
+                                [
+                                    substs["INSTALL_NAME_TOOL"],
+                                    "-id",
+                                    "@executable_path/" + DYLIB_NAME,
+                                    os.path.join(path, DYLIB_NAME),
+                                ]
+                            )
+                            dylibCopied = True
+                        else:
+                            sys.stderr.write(
+                                "dylib path in %s was not found at: %s\n"
+                                % (filename, copyDylibPath)
+                            )
+
+                    # Now use install_name_tool to rewrite the path in our binary
+                    relpath = "" if path == root else os.path.relpath(path, root) + "/"
+                    subprocess.check_call(
+                        [
+                            substs["INSTALL_NAME_TOOL"],
+                            "-change",
+                            absDylibPath,
+                            "@executable_path/" + relpath + DYLIB_NAME,
+                            filename,
+                        ]
+                    )
+                    break
+
+    if not dylibCopied:
+        sys.stderr.write("%s could not be found\n" % DYLIB_NAME)
+        sys.exit(1)
+
+
+if __name__ == "__main__":
+    for d in sys.argv[1:]:
+        scan_directory(d)