Add resolvers module

1 files changed, 79 insertions, 0 deletions

diff --git a/resolvers.sh b/resolvers.sh
new file mode 100644
index 0000000..ff4e38f
--- /dev/null
+++ b/resolvers.sh
@@ -0,0 +1,79 @@
+##
+# get_commit <version>
+#
+# Resolve a revision to a commit ID, exit via fatal error if
+# resolution cannot take place.
+##
+function get_commit
+{
+    # local repository #
+    if [[ "$remote" == "" ]]; then
+        if [[ "$1" == "HEAD" ]]; then
+            cat "$path/HEAD"
+
+        elif [[ "$1" == "BASE" ]]; then
+            cat ".systr/BASE"
+
+        elif [[ "$1" == "TRAC" ]]; then
+            cat ".systr/TRAC"
+
+        elif [[ "$1" == "NULL" ]]; then
+            echo "NULL"
+
+        elif [ -f "$path/refs/$1" ]; then
+            cat "$path/refs/$1"
+
+        elif [ -f "$path/$1/.commit.systr" ]; then
+            echo "$1"
+
+        else
+            echo "Error: $1 not a revision" >&2
+            exit
+        fi
+
+    # remote repository #
+    else
+        exit
+
+    fi
+}
+
+##
+# get_symref <version>
+#
+# Resolve a revision to a symbolic reference, exit via fatal
+# error if resolution cannot take place.
+##
+function get_symref
+{
+    # local repository #
+    if [[ "$remote" == "" ]]; then
+        if [[ "$1" == "HEAD" ]]; then
+            echo "HEAD"
+
+        elif [[ "$1" == "BASE" ]]; then
+            echo "BASE"
+
+        elif [[ "$1" == "TRAC" ]]; then
+            cat ".systr/TRAC"
+
+        elif [[ "$1" == "NULL" ]]; then
+            echo "NULL"
+
+        elif [ -f "$path/refs/$1" ]; then
+            echo "refs/$1"
+
+        elif [ -f "$path/$1/.commit.systr" ]; then
+            echo "$1"
+
+        else
+            echo "Error: $1 not a revision" >&2
+            exit
+        fi
+
+    # remote repository #
+    else
+        exit
+
+    fi
+}