#!/bin/bash
#---------------------------------------------------------------------
##
## @Synopsis Set of functions for dealing with the problem of having to
## @Synopsis use different version of the gcc compilers.
##
## The basic usage is as follows:
## <pre>
## - If a spell works with the latest version of gcc, do nothing.
## - To change the compiler version for a spell, add a GCC_VERSION field
##   to the spells DETAILS specifying major.minor version of gcc it needs,
##   e.g. GCC_VERSION=3.4
## - add a 'depends  gccXX' to the spell where XX == majorminor,
##   e.g. 'depends  gcc34'
## - add 'invoke_gcc' to the top of PRE_BUILD if the spell has a
##   custom PRE_BUILD file
## </pre>
##
## @Implementation These functions were added to allow the use of
## @Implementation several versions of gcc in parallel.
##
##
##  @Copyright Copyright 2005 by the Source Mage Team
##
##
#---------------------------------------------------------------------


#---------------------------------------------------------------------
## @param gcc version
## @return 0 if that gcc version is being used
## @return 1 otherwise
#---------------------------------------------------------------------
function use_gcc()  {

  gcc  -dumpversion  |  grep  -q  $(esc_str $1)  >  /dev/null

}

#---------------------------------------------------------------------
## @param new path to add
## @param old path
## @Stdout new path
## Echos the old path with new path prepended, separated with a ':'
#---------------------------------------------------------------------
function gcc_prepend_path()  {

  if    test  -z  $2
  then  echo $1
  else  echo $1:$2
  fi

}


#---------------------------------------------------------------------
## @param path
##
## Alters the environment so that the gcc in the specified directory
## will be used for compiling
##
#---------------------------------------------------------------------
function gcc_add_paths()  {

  export  PATH=$(  gcc_prepend_path  $1/bin  $PATH  )
  export  LD_LIBRARY_PATH=$(  gcc_prepend_path  $1/lib  $LD_LIBRARY_PATH  )
  export  LD_RUN_PATH=$(  gcc_prepend_path  $1/lib  $LD_RUN_PATH  )
  export  INFOPATH=$(  gcc_prepend_path  $1/info  $INFOPATH  )
  export  CPPFLAGS="-I $1/include  $CPPFLAGS"

}


#---------------------------------------------------------------------
##
## Determines if the spell specifies a gcc version to use. If so, it
## alters the environment so that that gcc version is used for compilation.
##
#---------------------------------------------------------------------
function invoke_gcc()  {

  if [[ "$GCC_VERSION" ]] && ! use_gcc $GCC_VERSION; then
    gcc_add_paths  /opt/gcc${GCC_VERSION//.}
    echo  "Overriding gcc version: `gcc -dumpversion`"
  fi

}


#---------------------------------------------------------------------
##
## This software is free software; you can redistribute it and/or modify
## it under the terms of the GNU General Public License as published by
## the Free Software Foundation; either version 2 of the License, or
## (at your option) any later version.
##
## This software is distributed in the hope that it will be useful,
## but WITHOUT ANY WARRANTY; without even the implied warranty of
## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
## GNU General Public License for more details.
##
## You should have received a copy of the GNU General Public License
## along with this software; if not, write to the Free Software
## Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
##
#---------------------------------------------------------------------