1 files changed, 84 insertions, 0 deletions
diff --git a/vendor/github.com/goamz/goamz/ec2/ec2test/filter.go b/vendor/github.com/goamz/goamz/ec2/ec2test/filter.go
new file mode 100644
index 000000000..1a0c04619
--- /dev/null
+++ b/vendor/github.com/goamz/goamz/ec2/ec2test/filter.go
@@ -0,0 +1,84 @@
+package ec2test
+
+import (
+	"fmt"
+	"net/url"
+	"strings"
+)
+
+// filter holds an ec2 filter.  A filter maps an attribute to a set of
+// possible values for that attribute. For an item to pass through the
+// filter, every attribute of the item mentioned in the filter must match
+// at least one of its given values.
+type filter map[string][]string
+
+// newFilter creates a new filter from the Filter fields in the url form.
+//
+// The filtering is specified through a map of name=>values, where the
+// name is a well-defined key identifying the data to be matched,
+// and the list of values holds the possible values the filtered
+// item can take for the key to be included in the
+// result set. For example:
+//
+//   Filter.1.Name=instance-type
+//   Filter.1.Value.1=m1.small
+//   Filter.1.Value.2=m1.large
+//
+func newFilter(form url.Values) filter {
+	// TODO return an error if the fields are not well formed?
+	names := make(map[int]string)
+	values := make(map[int][]string)
+	maxId := 0
+	for name, fvalues := range form {
+		var rest string
+		var id int
+		if x, _ := fmt.Sscanf(name, "Filter.%d.%s", &id, &rest); x != 2 {
+			continue
+		}
+		if id > maxId {
+			maxId = id
+		}
+		if rest == "Name" {
+			names[id] = fvalues[0]
+			continue
+		}
+		if !strings.HasPrefix(rest, "Value.") {
+			continue
+		}
+		values[id] = append(values[id], fvalues[0])
+	}
+
+	f := make(filter)
+	for id, name := range names {
+		f[name] = values[id]
+	}
+	return f
+}
+
+func notDigit(r rune) bool {
+	return r < '0' || r > '9'
+}
+
+// filterable represents an object that can be passed through a filter.
+type filterable interface {
+	// matchAttr returns true if given attribute of the
+	// object matches value. It returns an error if the
+	// attribute is not recognised or the value is malformed.
+	matchAttr(attr, value string) (bool, error)
+}
+
+// ok returns true if x passes through the filter.
+func (f filter) ok(x filterable) (bool, error) {
+next:
+	for a, vs := range f {
+		for _, v := range vs {
+			if ok, err := x.matchAttr(a, v); ok {
+				continue next
+			} else if err != nil {
+				return false, fmt.Errorf("bad attribute or value %q=%q for type %T: %v", a, v, x, err)
+			}
+		}
+		return false, nil
+	}
+	return true, nil
+}