First commit

vendor/github.com/lib/pq/hstore/hstore.go

@@ -0,0 +1,118 @@
+package hstore
+
+import (
+	"database/sql"
+	"database/sql/driver"
+	"strings"
+)
+
+// Hstore is a wrapper for transferring Hstore values back and forth easily.
+type Hstore struct {
+	Map map[string]sql.NullString
+}
+
+// escapes and quotes hstore keys/values
+// s should be a sql.NullString or string
+func hQuote(s interface{}) string {
+	var str string
+	switch v := s.(type) {
+	case sql.NullString:
+		if !v.Valid {
+			return "NULL"
+		}
+		str = v.String
+	case string:
+		str = v
+	default:
+		panic("not a string or sql.NullString")
+	}
+
+	str = strings.Replace(str, "\\", "\\\\", -1)
+	return `"` + strings.Replace(str, "\"", "\\\"", -1) + `"`
+}
+
+// Scan implements the Scanner interface.
+//
+// Note h.Map is reallocated before the scan to clear existing values. If the
+// hstore column's database value is NULL, then h.Map is set to nil instead.
+func (h *Hstore) Scan(value interface{}) error {
+	if value == nil {
+		h.Map = nil
+		return nil
+	}
+	h.Map = make(map[string]sql.NullString)
+	var b byte
+	pair := [][]byte{{}, {}}
+	pi := 0
+	inQuote := false
+	didQuote := false
+	sawSlash := false
+	bindex := 0
+	for bindex, b = range value.([]byte) {
+		if sawSlash {
+			pair[pi] = append(pair[pi], b)
+			sawSlash = false
+			continue
+		}
+
+		switch b {
+		case '\\':
+			sawSlash = true
+			continue
+		case '"':
+			inQuote = !inQuote
+			if !didQuote {
+				didQuote = true
+			}
+			continue
+		default:
+			if !inQuote {
+				switch b {
+				case ' ', '\t', '\n', '\r':
+					continue
+				case '=':
+					continue
+				case '>':
+					pi = 1
+					didQuote = false
+					continue
+				case ',':
+					s := string(pair[1])
+					if !didQuote && len(s) == 4 && strings.ToLower(s) == "null" {
+						h.Map[string(pair[0])] = sql.NullString{String: "", Valid: false}
+					} else {
+						h.Map[string(pair[0])] = sql.NullString{String: string(pair[1]), Valid: true}
+					}
+					pair[0] = []byte{}
+					pair[1] = []byte{}
+					pi = 0
+					continue
+				}
+			}
+		}
+		pair[pi] = append(pair[pi], b)
+	}
+	if bindex > 0 {
+		s := string(pair[1])
+		if !didQuote && len(s) == 4 && strings.ToLower(s) == "null" {
+			h.Map[string(pair[0])] = sql.NullString{String: "", Valid: false}
+		} else {
+			h.Map[string(pair[0])] = sql.NullString{String: string(pair[1]), Valid: true}
+		}
+	}
+	return nil
+}
+
+// Value implements the driver Valuer interface. Note if h.Map is nil, the
+// database column value will be set to NULL.
+func (h Hstore) Value() (driver.Value, error) {
+	if h.Map == nil {
+		return nil, nil
+	}
+	parts := []string{}
+	for key, val := range h.Map {
+		thispart := hQuote(key) + "=>" + hQuote(val)
+		parts = append(parts, thispart)
+	}
+	return []byte(strings.Join(parts, ",")), nil
+}