Support extracting archives to the packages we build

* BuildHaikuPackage rule: Create the script that contains the extraction
  commands.
* build_haiku_package: Add extractFile() function (stripped down version
  from build_haiku_image).

In build_haiku_image the functionality was mainly used to extract the
optional packages, which is no longer done. We still need it e.g. for
the Wifi firmware packages that want to be extracted.

build/scripts/build_haiku_package

@@ -56,6 +56,51 @@ rm=$rmAttrs
 mkindex=mkindex
 
 
+extractFile()
+{
+	# extractFile <archive> <directory> <extractedSubDir> <stripDebugSymbols>
+	archiveFile=$1
+	targetExtractedDir=$2
+	extractedSubDir=$3
+	# Ignore stripDebugSymbols. It's not relevant here, since executables and
+	# libraries shouldn't come from zip files or other archives anymore.
+
+	extractDir=$tmpDir/extract
+	$rmAttrs -rf "$extractDir"
+	mkdir -p "$extractDir"
+
+	case "$archiveFile" in
+		*.zip)
+			echo "Extracting $archiveFile ..."
+			$unzip -q -d "$extractDir" "$archiveFile"
+			;;
+		*.tgz|*.tar.gz)
+			echo "Extracting $archiveFile ..."
+			tar -C "$extractDir" -xf "$archiveFile"
+			;;
+		*.hpkg)
+			echo "Extracting $archiveFile ..."
+			if [ -n "$extractedSubDir" ]; then
+				$package extract -C "$extractDir" "$archiveFile" \
+					"$extractedSubDir"
+			else
+				$package extract -C "$extractDir" "$archiveFile"
+			fi
+			;;
+		*)
+			echo "Unhandled archive extension in build_haiku_image" \
+				"extractFile()"
+			exit 1
+			;;
+	esac
+
+	$cp -r "${sPrefix}$extractDir/$extractedSubDir/." \
+		"${tPrefix}$targetExtractedDir"
+
+	$rmAttrs -rf "$extractDir"
+}
+
+
 # execute the scripts preparing the package contents
 while [ $# -gt 0 ]; do
 	. $1