Using gdb_content_shell to attach to content_shell process directly.

build/android/gdb_apk

 #!/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.
 #
 # Attach gdb to a running android application.  Similar to ndk-gdb.
 # Run with --annotate=3 if running under emacs (M-x gdb).
 #
 # By default it is used to debug content shell, if it is used to
 # debug other piceces, '-p' and '-l' options are needed.
 # For *unittests_apk (like base_unittests_apk), run with:
 #  "gdb_apk -p org.chromium.native_test -l out/Release/lib.target -r"
 
+# Run a command through adb shell, strip the extra \r from the output
+# and return the correct status code to detect failures. This assumes
+# that the adb shell command prints a final \n to stdout.
+# $1+: command to run
+# Out: command's stdout
+# Return: command's status

[John Grabowski, 2012/07/19 18:19:26]

Doc is a little awkward; implies "return" is an arg.  Can you rephrase?
E.g. 
  args: command to run 
  Prints the command's stdout on stdout
  Returns the command's status.

[michaelbai, 2012/07/20 18:52:44]

Done.

+# Note: the command's stderr is lost
+adb_shell ()

[John Grabowski, 2012/07/19 18:19:26]

looks like convention for this file would be 

adb_shell() { 

[michaelbai, 2012/07/20 18:52:44]

Done.

+{
+  local TMPOUT="$(mktemp)"
+  local LASTLINE RET
+  local ADB=${ADB:-adb}
+
+  # The weird sed rule is to strip the final \r on each output line
+  # Since 'adb shell' never returns the command's proper exit/status code,
+  # we force it to print it as '%%<status>' in the temporary output file,
+  # which we will later strip from it.
+  $ADB shell $@ ";" echo "%%\$?" 2>/dev/null | sed -e 's![[:cntrl:]]!!g' > $TMPOUT
+  # Get last line in log, which contains the exit code from the command
+  LASTLINE=$(sed -e '$!d' $TMPOUT)
+  # Extract the status code from the end of the line, which must be '%%<code>'
+  RET=$(echo "$LASTLINE" | awk '{ if (match($0, "%%[0-9]+$")) { print substr($0,RSTART+2); } }')
+  # Remove the status code from the last line. Note that this may result in an empty line
+  LASTLINE=$(echo "$LASTLINE" | awk '{ if (match($0, "%%[0-9]+$")) { print substr($0,1,RSTART-1); } }')
+  # The output itself: all lines except the status code
+  sed -e '$d' $TMPOUT && echo -n "$LASTLINE"
+  # Remove temp file
+  rm -f $TMPOUT
+  # Exit with the appropriate status
+  return $RET
+}
+
 adb=$(which adb)
 if [[ "$adb" = "" ]] ; then
   echo "Need adb in your path"
   exit 1
 fi
 
 usage() {
   echo "usage: ${0##*/} [-p package_name] [-l shared_lib_dir] [-g gdb] [-r]"
   echo "-p package_name     the android APK package to be debugged"
   echo "-l shared_lib_dir   directory containes native shared library"
@@ skipping 54 matching lines @@
 # Kill any running gdbserver
 pid=$(adb shell ps | awk '/gdbserver/ {print $2}')
 if [[ "$pid" != "" ]] ; then
   if [[ $rooted_phone -eq 1 ]] ; then
     adb shell kill $pid
   else
     adb shell run-as $package_name kill $pid
   fi
 fi
 
-pid=$(adb shell ps | awk "/$package_name/ {print \$2}")
+pid=$(adb_shell ps | awk "/$package_name$/ {print \$2}")
 if [[ "$pid" = "" ]] ; then
   echo "No $package_name running?"
   echo "Try this: adb shell am start -a android.intent.action.VIEW " \
     "-n $package_name/.SomethingActivity (Something might be ContentShell)"
   exit 2
 fi
 
 no_gdb_server=$(adb shell ls $gdb_server_on_device | grep 'No such file')
 if [[ "$no_gdb_server" != "" ]] ; then
   echo "No gdb server on device at $gdb_server_on_device"
@@ skipping 30 matching lines @@
 if [[ ! -f ${gdb} ]] ; then
   echo "Wow no gdb in env var ANDROID_TOOLCHAIN which is $ANDROID_TOOLCHAIN"
   exit 4
 else
   echo Using $gdb
 fi
 
 # ${gdb} -x $cmdfile $* $app_process
 ${gdb} -x $cmdfile $gdb_args
 rm $cmdfile