t/built-sources-fork-bomb.sh

   1 #! /bin/sh
   2 # Copyright (C) 2012 Free Software Foundation, Inc.
   3 #
   4 # This program is free software; you can redistribute it and/or modify
   5 # it under the terms of the GNU General Public License as published by
   6 # the Free Software Foundation; either version 2, or (at your option)
   7 # any later version.
   8 #
   9 # This program is distributed in the hope that it will be useful,
  10 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 # GNU General Public License for more details.
  13 #
  14 # You should have received a copy of the GNU General Public License
  15 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16
  17 # Due to how the handling of $(BUILT_SOURCES) is implemented in Automake-NG,
  18 # a recursive make call in the recipe of any $(BUILT_SOURCES) (or of any of
  19 # its prerequisites) might cause an infinite recursion (complete with fork
  20 # bomb, yuck) if not handled correctly.  Verify that this doesn't happen.
  21 # For more background, see:
  22 # <http://lists.gnu.org/archive/html/help-smalltalk/2012-08/msg00027.html>
  23 # <http://lists.gnu.org/archive/html/automake-patches/2012-08/msg00052.html>
  24 # Backported to improve coverage of mainline Automake.
  25
  26 required=GNUmake
  27 . test-init.sh
  28
  29 echo AC_OUTPUT >> configure.ac
  30
  31 cat > Makefile.am << 'END'
  32 BUILT_SOURCES = foo
  33 .PHONY: build-foo
  34 build-foo:
  35         echo OK > foo
  36 foo:
  37         $(MAKE) build-foo
  38
  39 # If the bug is still present, we want this test to fail, not to actually
  40 # go fork bomb and potentially crash the user machine.  Take care of that.
  41
  42 is_too_deep := $(shell test $(MAKELEVEL) -lt 10 && echo no)
  43
  44 ## Extra indentation here required to avoid confusing Automake.
  45  ifeq ($(is_too_deep),no)
  46    # All is ok.
  47  else
  48    $(error ::OOPS:: Recursion too deep, $(MAKELEVEL) levels)
  49  endif
  50 END
  51
  52 $ACLOCAL
  53 $AUTOMAKE -Wno-portability
  54 $AUTOCONF
  55
  56 ./configure
  57
  58 $MAKE -n foo >output 2>&1 || { cat output; exit 1; }
  59 cat output
  60 test ! -f foo
  61 # Guard against possible infinite recursion.
  62 $FGREP '::OOPS::' output && exit 1
  63
  64 $MAKE foo >output 2>&1 || { cat output; exit 1; }
  65 cat output
  66 $MAKE foo
  67 # Guard against possible infinite recursion.
  68 $FGREP '::OOPS::' output && exit 1
  69
  70 :