configure

#!/bin/bash

###################################################################################
## Author: Stefan Lörwald, Universität Heidelberg                                ##
## License: CC BY-NC 4.0 http://creativecommons.org/licenses/by-nc/4.0/legalcode ##
###################################################################################

# Do not modify this file unless you know exactly what you're doing.

# This script tries to identify the compiler and if mpi is supported
# arguments are: --compiler=[] --no-mpi

# location of configuration files
compiler_filename=Makefile_configuration_compiler.mk;
mpi_filename=Makefile_configuration_mpi.mk;

# the generic header will be extracted from this file!
header=$(head -9 configure | tail -8);

# detect if the md5 sum is available with md5 or md5sum
if [ ! $(command -v md5sum 2> /dev/null) == "" ]
then
   MD5CHECKER=md5sum;
else
   if [ ! $(command -v md5 2> /dev/null) == "" ]
   then
      MD5CHECKER=md5;
   else
      echo "No way to check for md5 checksum. Please configure the files $(compiler_filename) and $(mpi_filename) manually."
   fi
fi

# see if any of the arguments is "--no-mpi"
try_mpi=1;
if [ "${1}" == "--no-mpi" ] || [ "${2}" == "--no-mpi" ] || [ "${3}" == "--no-mpi" ] || [ "${4}" == "--no-mpi" ] || [ "${5}" == "--no-mpi" ] || [ "${6}" == "--no-mpi" ] || [ "${7}" == "--no-mpi" ] || [ "${8}" == "--no-mpi" ] || [ "${9}" == "--no-mpi" ]
then
   try_mpi=0;
fi

# determine the MPI command
if [ ${try_mpi} -eq 1 ]
then
   if [ ! $(command -v mpic++ 2> /dev/null) == "" ]
   then
      command=mpic++;
   elif [ ! $(command -v mpicxx 2> /dev/null) == "" ]
   then
      command=mpicxx;
   elif [ ! $(command -v mpicc 2> /dev/null) == "" ]
   then
      command=mpicc;
   else
      echo "No MPI compiler found. Please enter the MPI compiler invocation command or \"N\" for not using MPI:";
      read command;
   fi
fi

mpi_information="# MPI configuration: the following items must be checked against your MPI installation.
# Run \"mpic++ --showme:compile\" / \"mpic++ --showme:link\" or similar to identify the compiler
# options enabled by a call of \"mpic++ foo.cpp\".
# If your software configuration doesn't support MPI, disable all of the following lines.";
if [ ${try_mpi} -eq 1 ] && [ ${command} != "N" ]
then
   # using the MPI invocation to get compiler flags. This is usually something like g++ -L/mpi/ -lmpi
   # the correct command is dependent on the MPI distribution. We try a bunch of "show-me" commands.
   compile_command=$(${command} --show-me:compile 2> /dev/null);
   compile_command_valid=$?;
   link_command=$(${command} --show-me:link 2> /dev/null);
   link_command_valid=$?;
   generic_command_valid=1;
   generic_command=$(${command} --show-me 2> /dev/null);
   if [ $? -gt 0 ]
   then
      generic_command=$(${command} --showme 2> /dev/null);
      if [ $? -gt 0 ]
      then
         generic_command=$(${command} --show 2> /dev/null);
         if [ $? -gt 0 ]
         then
            generic_command=$(${command} -show 2> /dev/null);
            if [ $? -gt 0 ]
            then
               generic_command=$(${command} -showme 2> /dev/null);
               if [ $? -gt 0 ]
               then
                  generic_command=$(${command} -compile_info 2> /dev/null);
                  generic_command_valid=$?;
               else
                  generic_command_valid=0;
               fi
            else
               generic_command_valid=0;
            fi
         else
            generic_command_valid=0;
         fi
      else
         generic_command_valid=0;
      fi
   else
      generic_command_valid=0;
   fi
   if [ ${compile_command_valid} -eq 0 ] && [ ${link_command_valid} -eq 0 ]
   then
      flags_library_headers=$(echo "${compile_command}" | sed 's/\b[^-][^ ]* //' | sed 's/ -l[^ ]*//g' | sed 's/ -Wl,[^ ]*//g' | sed 's/ -L[^ ]*//g');
      flags_library_objects=$(echo "${link_command}" | sed 's/\b[^-][^ ]* //');
   elif [ ${generic_command_valid} -eq 0 ]
   then
      flags_library_headers=$(echo "${generic_command}" | sed 's/\b[^-][^ ]* //' | sed 's/ -l[^ ]*//g' | sed 's/ -Wl,[^ ]*//g' | sed 's/ -L[^ ]*//g');
      flags_library_objects=$(echo "${generic_command}" | sed 's/\b[^-][^ ]* //');
   else
      echo "Couldn't identify MPI configuration (${command} usually invokes an underlying compiler such as gcc with some flags. This script was not able to identify these flags. Usually, this can be extracted with \"${command} --show\" or a similar command. If you happen to know how to do this with your copy of MPI, please send feedback to the address provided in the README file). Sorry, we cannot continue like this, your only option right now is to run this again with the option \"--no-mpi\".";
      exit 1;
   fi
   # Writing the gathered information to temporary file
   printf "${header}\n${mpi_information}\n\n" > .tmp_mpi;
   printf "flags_configuration   += -DMPI_SUPPORT\n" >> .tmp_mpi;
   printf "flags_library_headers += ${flags_library_headers}\n" >> .tmp_mpi;
   printf "flags_library_objects += ${flags_library_objects}\n\n" >> .tmp_mpi;
else
   # Writing the gathered information to temporary file
   printf "${header}\n${mpi_information}\n\n" > .tmp_mpi;
   printf "# flags_configuration   += -DMPI_SUPPORT\n" >> .tmp_mpi;
   printf "# flags_library_headers +=\n" >> .tmp_mpi;
   printf "# flags_library_objects +=\n\n" >> .tmp_mpi;
fi
if [ $(cat .tmp_mpi | ${MD5CHECKER} | cut -d" " -f1) == $(cat ${mpi_filename} 2> /dev/null | ${MD5CHECKER} | cut -d" " -f1) ]
then
   echo "Writing MPI configuration omitted: configuration didn't change.";
   rm .tmp_mpi;
else
   printf "Writing MPI configuration: ";
   mv .tmp_mpi ${mpi_filename};
   if [ $? -eq 0 ]
   then
      printf "done\n"; 
   else
      printf "failed\n";
      exit 1;
   fi
fi
# MPI configuration is done here.

# look if there is an option specifying the compiler
if [[ "${1}" == "--compiler="* ]]
then
   user_compiler=$(echo "${1}" | cut -d= -f2);
elif [[ "${2}" == "--compiler="* ]]
then
   user_compiler=$(echo "${2}" | cut -d= -f2);
elif [[ "${3}" == "--compiler="* ]]
then
   user_compiler=$(echo "${3}" | cut -d= -f2);
elif [[ "${4}" == "--compiler="* ]]
then
   user_compiler=$(echo "${4}" | cut -d= -f2);
elif [[ "${5}" == "--compiler="* ]]
then
   user_compiler=$(echo "${5}" | cut -d= -f2);
elif [[ "${6}" == "--compiler="* ]]
then
   user_compiler=$(echo "${6}" | cut -d= -f2);
elif [[ "${7}" == "--compiler="* ]]
then
   user_compiler=$(echo "${7}" | cut -d= -f2);
elif [[ "${8}" == "--compiler="* ]]
then
   user_compiler=$(echo "${8}" | cut -d= -f2);
elif [[ "${9}" == "--compiler="* ]]
then
   user_compiler=$(echo "${9}" | cut -d= -f2);
else
   user_compiler=;
fi

# now we try to detect a compatible compiler
# compilers are tried in the order COMMAND-LINE, g++, clang++, ask user.
command=;
gcc_major_version=$(g++ -v 2>&1 | grep 'gcc version' | sed 's/.*version //' | sed 's/ .*//' | cut -d. -f1 && echo '0');
gcc_major_version=$(echo "${gcc_major_version}" | head -n 1);
gcc_minor_version=$(g++ -v 2>&1 | grep 'gcc version' | sed 's/.*version //' | sed 's/ .*//' | cut -d. -f2 && echo '0');
gcc_minor_version=$(echo "${gcc_minor_version}" | head -n 1);
clang_major_version=$(clang++ -v 2>&1 | grep 'based on LLVM' | sed 's/.*on LLVM //' | cut -c1-3 | cut -d. -f1 && echo '0');
clang_major_version=$(echo "${clang_major_version}" | head -n 1);
clang_minor_version=$(clang++ -v 2>&1 | grep 'based on LLVM' | sed 's/.*on LLVM //' | cut -c1-3 | cut -d. -f2 && echo '0');
clang_minor_version=$(echo "${clang_minor_version}" | head -n 1);

if [ ! ${user_compiler} == "" ]
then
   if [ ! $(command -v ${user_compiler} 2> /dev/null) == "" ]
   then
      command=${user_compiler};
   else
      echo "Sorry, cannot use \"${user_compiler}\" as a compiler. Contact us via the address provided in the README file if this seems weird to you.";
   fi
elif [ ! $(command -v g++ 2> /dev/null) == "" ] && [ ${gcc_major_version} -ge 4 ] && ([ ${gcc_major_version} -gt 4 ] || [ ${gcc_minor_version} -ge 7 ]); # g++ is compatible since g++-4.7
then
   command=g++;
elif [ ! $(command -v clang++ 2> /dev/null) == "" ] && [ ${clang_major_version} -ge 3 ] && ([ ${clang_major_version} -gt 3 ] || [ ${clang_minor_version} -ge 4 ]); # clang++ is compatible since clang++-3.4
then
   command=clang++;
else
   echo "No compatible compiler found. Please enter the compiler invocation command:";
   read command;
   if [ ! $(command -v ${command} 2> /dev/null) == "" ]
   then
      echo "This compiler is not supported. If the build is successful anyway, please contact us via the address provided in the README file.";
   else
      echo "Sorry, we couldn't find your compiler.";
      exit 1;
   fi
fi

# Writing the gathered information to temporary file
printf "${header}\n\n" > .tmp_compiler;
printf "COMPILER = ${command}\n" >> .tmp_compiler;
printf "LINKER = \$(COMPILER)\n\n" >> .tmp_compiler;

# Writing to actual file (if necessary)
if [ $(cat .tmp_compiler | ${MD5CHECKER} | cut -d" " -f1) == $(cat ${compiler_filename} 2> /dev/null | ${MD5CHECKER} | cut -d" " -f1) ]
then
   echo "Writing compiler configuration omitted: configuration didn't change.";
   rm .tmp_compiler;
else
   printf "Writing compiler configuration: ";
   mv .tmp_compiler ${compiler_filename};
   if [ $? -eq 0 ]
   then
      printf "done\n"; 
   else
      printf "failed\n";
      exit 1;
   fi
fi