#!/bin/bash
# Copyright (c) 2012 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.
#
# Saves the gdb index for a given binary and its shared library dependencies.

set -e

if [[ ! $# == 1 ]]; then
  echo "Usage: $0 path-to-binary"
  exit 1
fi

FILENAME="$1"
if [[ ! -f "$FILENAME" ]]; then
  echo "Path $FILENAME does not exist."
  exit 1
fi

# We're good to go! Create temp directory for index files.
DIRECTORY=$(mktemp -d)
echo "Made temp directory $DIRECTORY."

# Always remove directory on exit.
trap "{ echo -n Removing temp directory $DIRECTORY...;
  rm -rf $DIRECTORY; echo done; }" EXIT

# Grab all the chromium shared library files.
so_files=$(ldd "$FILENAME" 2>/dev/null \
  | grep $(dirname "$FILENAME") \
  | sed "s/.*[ \t]\(.*\) (.*/\1/")

# Add index to binary and the shared library dependencies.
for file in "$FILENAME" $so_files; do
  basename=$(basename "$file")
  echo -n "Adding index to $basename..."
  readelf_out=$(readelf -S "$file")
  if [[ $readelf_out =~ "gdb_index" ]]; then
    echo "already contains index. Skipped."
  else
    gdb -batch "$file" -ex "save gdb-index $DIRECTORY" -ex "quit"
    objcopy --add-section .gdb_index="$DIRECTORY"/$basename.gdb-index \
      --set-section-flags .gdb_index=readonly "$file" "$file"
    echo "done."
  fi
done