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-rwxr-xr-xthird_party/libwebrtc/build/toolchain/gcc_solink_wrapper.py198
1 files changed, 198 insertions, 0 deletions
diff --git a/third_party/libwebrtc/build/toolchain/gcc_solink_wrapper.py b/third_party/libwebrtc/build/toolchain/gcc_solink_wrapper.py
new file mode 100755
index 0000000000..39aef4d1e9
--- /dev/null
+++ b/third_party/libwebrtc/build/toolchain/gcc_solink_wrapper.py
@@ -0,0 +1,198 @@
+#!/usr/bin/env python
+# Copyright 2015 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""Runs 'ld -shared' and generates a .TOC file that's untouched when unchanged.
+
+This script exists to avoid using complex shell commands in
+gcc_toolchain.gni's tool("solink"), in case the host running the compiler
+does not have a POSIX-like shell (e.g. Windows).
+"""
+
+import argparse
+import os
+import shlex
+import subprocess
+import sys
+
+import wrapper_utils
+
+
+def CollectSONAME(args):
+ """Replaces: readelf -d $sofile | grep SONAME"""
+ toc = ''
+ readelf = subprocess.Popen(wrapper_utils.CommandToRun(
+ [args.readelf, '-d', args.sofile]),
+ stdout=subprocess.PIPE,
+ bufsize=-1,
+ universal_newlines=True)
+ for line in readelf.stdout:
+ if 'SONAME' in line:
+ toc += line
+ return readelf.wait(), toc
+
+
+def CollectDynSym(args):
+ """Replaces: nm --format=posix -g -D -p $sofile | cut -f1-2 -d' '"""
+ toc = ''
+ nm = subprocess.Popen(wrapper_utils.CommandToRun(
+ [args.nm, '--format=posix', '-g', '-D', '-p', args.sofile]),
+ stdout=subprocess.PIPE,
+ bufsize=-1,
+ universal_newlines=True)
+ for line in nm.stdout:
+ toc += ' '.join(line.split(' ', 2)[:2]) + '\n'
+ return nm.wait(), toc
+
+
+def CollectTOC(args):
+ result, toc = CollectSONAME(args)
+ if result == 0:
+ result, dynsym = CollectDynSym(args)
+ toc += dynsym
+ return result, toc
+
+
+def UpdateTOC(tocfile, toc):
+ if os.path.exists(tocfile):
+ old_toc = open(tocfile, 'r').read()
+ else:
+ old_toc = None
+ if toc != old_toc:
+ open(tocfile, 'w').write(toc)
+
+
+def CollectInputs(out, args):
+ for x in args:
+ if x.startswith('@'):
+ with open(x[1:]) as rsp:
+ CollectInputs(out, shlex.split(rsp.read()))
+ elif not x.startswith('-') and (x.endswith('.o') or x.endswith('.a')):
+ out.write(x)
+ out.write('\n')
+
+
+def InterceptFlag(flag, command):
+ ret = flag in command
+ if ret:
+ command.remove(flag)
+ return ret
+
+
+def main():
+ parser = argparse.ArgumentParser(description=__doc__)
+ parser.add_argument('--readelf',
+ required=True,
+ help='The readelf binary to run',
+ metavar='PATH')
+ parser.add_argument('--nm',
+ required=True,
+ help='The nm binary to run',
+ metavar='PATH')
+ parser.add_argument('--strip',
+ help='The strip binary to run',
+ metavar='PATH')
+ parser.add_argument('--dwp', help='The dwp binary to run', metavar='PATH')
+ parser.add_argument('--sofile',
+ required=True,
+ help='Shared object file produced by linking command',
+ metavar='FILE')
+ parser.add_argument('--tocfile',
+ required=True,
+ help='Output table-of-contents file',
+ metavar='FILE')
+ parser.add_argument('--map-file',
+ help=('Use --Wl,-Map to generate a map file. Will be '
+ 'gzipped if extension ends with .gz'),
+ metavar='FILE')
+ parser.add_argument('--output',
+ required=True,
+ help='Final output shared object file',
+ metavar='FILE')
+ parser.add_argument('command', nargs='+',
+ help='Linking command')
+ args = parser.parse_args()
+
+ # Work-around for gold being slow-by-default. http://crbug.com/632230
+ fast_env = dict(os.environ)
+ fast_env['LC_ALL'] = 'C'
+
+ # Extract flags passed through ldflags but meant for this script.
+ # https://crbug.com/954311 tracks finding a better way to plumb these.
+ link_only = InterceptFlag('--link-only', args.command)
+ collect_inputs_only = InterceptFlag('--collect-inputs-only', args.command)
+
+ # If only linking, we are likely generating a partitioned .so that will be
+ # split apart later. In that case:
+ #
+ # - The TOC file optimization isn't useful, because the partition libraries
+ # must always be re-extracted if the combined library changes (and nothing
+ # should be depending on the combined library's dynamic symbol table).
+ # - Stripping isn't necessary, because the combined library is not used in
+ # production or published.
+ #
+ # Both of these operations could still be done, they're needless work, and
+ # tools would need to be updated to handle and/or not complain about
+ # partitioned libraries. Instead, to keep Ninja happy, simply create dummy
+ # files for the TOC and stripped lib.
+ if link_only or collect_inputs_only:
+ open(args.output, 'w').close()
+ open(args.tocfile, 'w').close()
+ if args.dwp:
+ open(args.sofile + '.dwp', 'w').close()
+
+ # Instead of linking, records all inputs to a file. This is used by
+ # enable_resource_allowlist_generation in order to avoid needing to
+ # link (which is slow) to build the resources allowlist.
+ if collect_inputs_only:
+ with open(args.sofile, 'w') as f:
+ CollectInputs(f, args.command)
+ if args.map_file:
+ open(args.map_file, 'w').close()
+ return 0
+
+ # First, run the actual link.
+ command = wrapper_utils.CommandToRun(args.command)
+ result = wrapper_utils.RunLinkWithOptionalMapFile(command,
+ env=fast_env,
+ map_file=args.map_file)
+
+ if result != 0 or link_only:
+ return result
+
+ # If dwp is set, then package debug info for this SO.
+ dwp_proc = None
+ if args.dwp:
+ # Suppress output here because it doesn't seem to be useful. The most
+ # common error is a segfault, which will happen if files are missing.
+ with open(os.devnull, "w") as devnull:
+ dwp_proc = subprocess.Popen(wrapper_utils.CommandToRun(
+ [args.dwp, '-e', args.sofile, '-o', args.sofile + '.dwp']),
+ stdout=devnull,
+ stderr=subprocess.STDOUT)
+
+ # Next, generate the contents of the TOC file.
+ result, toc = CollectTOC(args)
+ if result != 0:
+ return result
+
+ # If there is an existing TOC file with identical contents, leave it alone.
+ # Otherwise, write out the TOC file.
+ UpdateTOC(args.tocfile, toc)
+
+ # Finally, strip the linked shared object file (if desired).
+ if args.strip:
+ result = subprocess.call(wrapper_utils.CommandToRun(
+ [args.strip, '-o', args.output, args.sofile]))
+
+ if dwp_proc:
+ dwp_result = dwp_proc.wait()
+ if dwp_result != 0:
+ return dwp_result
+
+ return result
+
+
+if __name__ == "__main__":
+ sys.exit(main())