unpack source function unpacks tarballs (very hard)

1 files changed, 38 insertions, 0 deletions

diff --git a/snag/scripts/extract_tar_contents.sh b/snag/scripts/extract_tar_contents.sh
new file mode 100755
index 0000000..a50a1a7
--- /dev/null
+++ b/snag/scripts/extract_tar_contents.sh
@@ -0,0 +1,38 @@
+#!/bin/sh
+set -e
+
+# extracts a tarball's contents to the output directory.
+# if the tarball contains just one directory, extract those contents
+#
+# we can rewrite this script in c eventually, if we want
+
+if [ -z "$1" -o -z "$2" ]; then
+    echo "Usage: $0 <tarball> <output_directory>" >&2
+    exit 1
+fi
+
+tarball="$1"
+target="$2"
+
+is_one_directory() {
+	if [ $(echo $1 | wc -l) -ne 1 ]; then
+		return 1
+	fi
+	case "$1" in
+		*/) return 0 ;;
+		*)  return 1 ;;
+	esac
+}
+
+# get top level paths in tarball
+tlps=$(tar -tf "$tarball" | grep -E '^(./)?[^/]+/?$')
+
+if is_one_directory "$tlps"; then
+	# if only one top level directory, extract it and rename it
+	tar xf "$tarball"
+	mv "$tlps" "$target"
+else
+	# if a bunch of files or directories, extract them in a directory
+	mkdir $target
+	tar xf "$tarball" -C "$target"
+fi