Add rdf2hdtcat.sh from hdt-java

This is not in the package. This includes my patches to the upstream
script at <rdfhdt/hdt-java#201>.

bin/hdt-java-rdf2hdtcat.sh

@@ -0,0 +1,106 @@
+#!/bin/bash
+
+function showhelp {
+	echo
+	echo "Script to serialize a big RDF file in n-triples format into HDT"
+	echo "It splits the file in N parts, compress each one with rdf2hdt, and merges them iteratively with hdtCat."
+	echo
+	echo "Usage $0 [OPTION]"
+	echo
+    echo "  -c, --catscript location of hdtCat script  (assuming it's in PATH by by default)"
+    echo "  -i, --input     input file (input.rdf by default)"
+	echo "  -h, --help      shows this help and exits"
+	echo "  -n, --number    number of files to split FILE (2 by default)"
+    echo "  -o, --output    output file (output.hdt by default)"
+    echo "  -p, --parallel  number of threads to serialize RDF into HDT in parallel (1 by default)"
+    echo "  -r, --rdf2hdt   location of rdf2hdt script (assuming it's in PATH by default)"
+	echo
+}
+
+# Defaults
+declare rdf2hdt="rdf2hdt.sh"
+declare hdtCat="hdtCat.sh"
+declare input="input.rdf"
+declare -i lines
+declare output="output.hdt"
+declare -i splits=2
+declare -i threads=1
+
+getopt --test > /dev/null
+if [[ $? -eq 4 ]]; then
+    # enhanced getopt works
+    OPTIONS=c:i:hn:o:p:r:
+    LONGOPTIONS=cat:,input:,help,number:,output:,parallel:,rdf2hdt:
+    COMMAND=$(getopt -o $OPTIONS -l $LONGOPTIONS -n "$0" -- "$@")
+    if [[ $? -ne 0 ]]; then
+    	exit 2
+    fi
+    eval set -- "$COMMAND"
+else
+	echo "Enhanced getopt not supported. Brace yourself, this is not tested, but it should work :-)"
+fi
+
+while true; do
+	case "$1" in
+        -c|--cat)
+            hdtCat=$2
+            shift 2
+            ;;
+        -i|--input)
+            input=$2
+            shift 2
+            ;;
+		-n|--number)
+			splits=$2
+			shift 2
+			;;
+        -o|--output)
+            output=$2
+            shift 2
+            ;;
+        -p|--parallel)
+            threads=$2
+            shift 2
+            ;;
+        -r|--rdf2hdt)
+            rdf2hdt=$2
+            shift 2
+            ;;
+		--)
+			shift
+			break
+			;;
+		*)
+			showhelp
+			exit 0
+			;;
+	esac
+done
+
+total_lines=$(wc -l < $input)
+lines=($total_lines+$splits-1)/$splits #Set number of lines rounding up
+
+split -l $lines $input "$input"_split_
+
+echo "***************************************************************"
+echo "Serializing into HDT $splits files using $threads threads"
+echo "***************************************************************"
+echo -n "$input"_split_* | xargs -I{} -d' ' -P$threads $rdf2hdt -rdftype ntriples {} {}_"$splits".hdt
+
+for (( i=$splits; i>1; i=i/2 )); do
+    echo "***************************************************************"
+    echo "Merging $i hdt files: " "$input"_split_*_"$i".hdt
+    echo "***************************************************************"
+    command='temp=${2%_*.hdt} ; '$hdtCat' $1 $2 ${1%_*.hdt}_${temp#*split_}_$0.hdt'
+    echo -n "$input"_split_*_"$i".hdt | xargs -d' ' -n2 -P$threads bash -c "$command" $((i/2))
+done
+
+echo "***************************************************************"
+echo "Moving output to '$output' file"
+echo "***************************************************************"
+mv "$input"_split*_1.hdt "$output"
+
+echo "***************************************************************"
+echo "Cleaning up split files"
+echo "***************************************************************"
+rm "$input"_split_*