#!/bin/bash

# Copyright (c) 2011 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.

# This script makes sure that no __OBJC,__image_info section appears in the
# executable file built by the Xcode target that runs the script. If such a
# section appears, the script prints an error message and exits nonzero.
#
# Why is this important?
#
# On 10.5, there's a bug in CFBundlePreflightExecutable that causes it to
# crash when operating in an executable that has not loaded at its default
# address (that is, when it's a position-independent executable with the
# MH_PIE bit set in its mach_header) and the executable has an
# __OBJC,__image_info section. See http://crbug.com/88697.
#
# Chrome's main executables don't use any Objective-C at all, and don't need
# to carry this section around. Not linking them as Objective-C when they
# don't need it anyway saves about 4kB in the linked executable, although most
# of that 4kB is just filled with zeroes.
#
# This script makes sure that nobody goofs and accidentally introduces these
# sections into the main executables.

set -eu

global executable := ""$(BUILT_PRODUCTS_DIR)/$(EXECUTABLE_PATH)""

if xcrun otool -arch i386 -o $(executable) | grep -q '^Contents.*section$' \
{
  echo "$(0): $(executable) has an __OBJC,__image_info section" !2 > !1
  exit 1
}

if [[ ${PIPESTATUS[0]} -ne 0 ]] {
  echo "$(0): otool failed" !2 > !1
  exit 1
}

exit 0
(CommandList
  children: [
    (C {(set)} {(-eu)})
    (Assignment
      keyword: Assign_None
      pairs: [
        (assign_pair
          lhs: (LhsName name:executable)
          op: Equal
          rhs: {(DQ (${ VSub_Name BUILT_PRODUCTS_DIR) (/) (${ VSub_Name EXECUTABLE_PATH))}
          spids: [77]
        )
      ]
      spids: [77]
    )
    (If
      arms: [
        (if_arm
          cond: [
            (Sentence
              child: 
                (Pipeline
                  children: [
                    (C {(xcrun)} {(otool)} {(-arch)} {(i386)} {(-o)} {(DQ (${ VSub_Name executable))})
                    (C {(grep)} {(-q)} {(SQ <"^Contents.*section$">)})
                  ]
                  negated: False
                )
              terminator: <Op_Semi ";">
            )
          ]
          action: [
            (SimpleCommand
              words: [
                {(echo)}
                {
                  (DQ (${ VSub_Number 0) (": ") (${ VSub_Name executable) 
                    (" has an __OBJC,__image_info section")
                  )
                }
              ]
              redirects: [(Redir op_id:Redir_GreatAnd fd:2 arg_word:{(1)} spids:[135])]
            )
            (C {(exit)} {(1)})
          ]
          spids: [-1 119]
        )
      ]
      spids: [-1 143]
    )
    (If
      arms: [
        (if_arm
          cond: [
            (Sentence
              child: 
                (DBracket
                  expr: 
                    (BoolBinary
                      op_id: BoolBinary_ne
                      left: 
                        {
                          (BracedVarSub
                            token: <VSub_Name PIPESTATUS>
                            bracket_op: (ArrayIndex expr:(ArithWord w:{(Lit_Digits 0)}))
                            spids: [150 155]
                          )
                        }
                      right: {(0)}
                    )
                )
              terminator: <Op_Semi ";">
            )
          ]
          action: [
            (SimpleCommand
              words: [{(echo)} {(DQ (${ VSub_Number 0) (": otool failed"))}]
              redirects: [(Redir op_id:Redir_GreatAnd fd:2 arg_word:{(1)} spids:[176])]
            )
            (C {(exit)} {(1)})
          ]
          spids: [-1 164]
        )
      ]
      spids: [-1 184]
    )
    (C {(exit)} {(0)})
  ]
)