#!/bin/sh
# This file is a part of Julia. License is MIT: https://julialang.org/license

# Run as: fixup-libgfortran.sh [--verbose] <$private_libdir>

# If we're invoked with "--verbose", create a `debug` function that prints stuff out
if test $1 == "--verbose" || test $1 == "-v" {
shift 1
proc debug { echo "$ifsjoin(Argv)"; }
} else {
proc debug { :; }
}

if test -z $1 {
    echo "Usage: $0 <private_libdir>"
    exit 1
}

setglobal UNAME = $[uname -s]
if test $UNAME = "Linux" {
    setglobal SHLIB_EXT = '"so'"
} elif test $UNAME = "Darwin" {
    setglobal SHLIB_EXT = '"dylib'"
} else {
    echo "WARNING: Could not autodetect platform type ('uname -s' == $UNAME); assuming Linux" > !2
    setglobal UNAME = '"Linux'"
    setglobal SHLIB_EXT = '"so'"
}

setglobal private_libdir = $1

if test ! -f "$private_libdir/libarpack.$SHLIB_EXT" {
    echo "ERROR: Could not open $private_libdir/libarpack.$SHLIB_EXT" > !2
    exit 2
}

proc find_shlib
{
    setglobal lib_path = $1
    if test -f $lib_path {
        if test $UNAME = "Linux" {
            ldd $lib_path | grep $2 | cut -d' ' -f3 | xargs
        } else { # $UNAME is "Darwin", we only have two options, see above
            otool -L $lib_path | grep $2 | cut -d' ' -f1 | xargs
        }
    }
}

proc private_libname
{
    echo "$private_libdir/lib$1.$SHLIB_EXT"
}

# First, discover all the places where libgfortran/libgcc is, as well as their true SONAMES
for lib in [arpack lapack] {
    if test -f "$private_libdir/lib$lib.$SHLIB_EXT" {
        # Find the paths to the libraries we're interested in.  These are almost
        # always within the same directory, but we like to be general.
        setglobal LIBGFORTRAN_PATH = $[find_shlib $[private_libname $lib] libgfortran]
        setglobal LIBGCC_PATH = $[find_shlib $[private_libname $lib] libgcc_s]
        setglobal LIBQUADMATH_PATH = $[find_shlib $[private_libname $lib] libquadmath]

        # Take the directories, add them onto LIBGFORTRAN_DIRS, which we use to
        # search for these libraries in the future.
        setglobal LIBGFORTRAN_DIRS = ""$LIBGFORTRAN_DIRS $[dirname $LIBGFORTRAN_PATH]""
        setglobal LIBGFORTRAN_DIRS = ""$LIBGFORTRAN_DIRS $[dirname $LIBGCC_PATH]""
        setglobal LIBGFORTRAN_DIRS = ""$LIBGFORTRAN_DIRS $[dirname $LIBQUADMATH_PATH]""

        # Save the SONAMES
        setglobal LIBGFORTRAN_SONAMES = ""$LIBGFORTRAN_SONAMES $[basename $LIBGFORTRAN_PATH]""
        setglobal LIBGCC_SONAMES = ""$LIBGCC_SONAMES $[basename $LIBGCC_PATH]""
        setglobal LIBQUADMATH_SONAMES = ""$LIBQUADMATH_SONAMES $[basename $LIBQUADMATH_PATH]""
    }
}

# Take in a list of space-separated tokens, return a deduplicated list of the same
proc uniquify
{
    echo $1 | tr " " "\n" | sort | uniq | grep -v '^$' | tr "\n" " "
}

setglobal LIBGFORTRAN_DIRS = $[uniquify $LIBGFORTRAN_DIRS]
setglobal SONAMES = $[uniquify "$LIBGFORTRAN_SONAMES $LIBGCC_SONAMES $LIBQUADMATH_SONAMES]
debug "Discovered traces of libgfortran within $LIBGFORTRAN_DIRS"
debug "Got SONAMES of $SONAMES"

# Copy the SONAMEs we identified above into our private_libdir
for soname in [$SONAMES] {
    for dir in [$LIBGFORTRAN_DIRS] {
        if test ! -f "$private_libdir/$soname" && test -f "$dir/$soname" {
            cp -v "$dir/$soname" $private_libdir
            chmod 755 "$private_libdir/$soname"
            if test $UNAME = "Darwin" {
                install_name_tool -id "@rpath/$soname" "$private_libdir/$soname"
            }
        }
    }
}

# On OSX, we need to change the old link (which is usually a full path)
# to point to `@rpath/${soname}` explicitly, so we use `find_shlib()`
# to dynamically find the full path we want to change.  On Linux, we
# don't care about full paths, we just set the rpath to `$ORIGIN`.
proc change_linkage
{
    # This is the path of the library we want to edit
    setglobal lib_path = $1

    # If it doesn't exist, exit quietly
    if test ! -f $lib_path {
        debug "  $lib_path doesn't exist, skipping"
        return
    }

    # This is the soname of the dependency we want to swap out
    setglobal soname = $2

    if test $UNAME = "Darwin" {
        setglobal old_link = $[find_shlib $lib_path $soname]
        echo " $old_link"
        install_name_tool -change $old_link "@rpath/$soname" $lib_path
    } else { # $UNAME is "Linux", we only have two options, see above
        patchelf --set-rpath '$'ORIGIN $lib_path
    }
}

# For every library that remotely touches libgfortran stuff (the libraries we
# have copied in ourselves as well as arpack, etc...) we must
# update the linkage to point to @rpath (on OSX) or $ORIGIN (on Linux) so
# that direct links to the old libgfortran directories are instead directed
# to the proper location, which is our $private_libdir.
for lib in [libopenblas libarpack libcholmod liblapack $SONAMES] {
    # Grab every incarnation of that library that exists within $private_libdir
    # (e.g. "libopenblas.so", and "libopenblas.so.0", etc...)
    for lib_path in [$private_libdir/$lib*] {
        # Iterate over dependency names that need to be changed
        for soname in [$SONAMES] {
            debug "changing linkage of $lib_path to $soname"
            change_linkage $lib_path $soname
        }
    }
}