1 files changed, 77 insertions, 0 deletions
diff --git a/config.go b/config.go
new file mode 100644
index 0000000..c6a40ac
--- /dev/null
+++ b/config.go
@@ -0,0 +1,77 @@
+package main
+
+import (
+	"bufio"
+	"fmt"
+	"io"
+	"os"
+	"regexp"
+	"strings"
+	"sync"
+)
+
+type Route struct {
+	match   *regexp.Regexp
+	backend string
+}
+
+// Config stores the TLS routing configuration.
+type Config struct {
+	mu     sync.Mutex
+	routes []Route
+}
+
+func dnsRegex(s string) (*regexp.Regexp, error) {
+	return regexp.Compile(s)
+}
+
+func (c *Config) Match(hostname string) string {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	for _, r := range c.routes {
+		if r.match.MatchString(hostname) {
+			return r.backend
+		}
+	}
+	return ""
+}
+
+func (c *Config) Read(r io.Reader) error {
+	var routes []Route
+
+	s := bufio.NewScanner(r)
+	for s.Scan() {
+		fs := strings.Fields(s.Text())
+		switch len(fs) {
+		case 0:
+			continue
+		case 1:
+			return fmt.Errorf("invalid %q on a line by itself", s.Text())
+		case 2:
+			re, err := dnsRegex(fs[0])
+			if err != nil {
+				return err
+			}
+			routes = append(routes, Route{re, fs[1]})
+		default:
+			// TODO: multiple backends?
+			return fmt.Errorf("too many fields on line: %q", s.Text())
+		}
+	}
+	if err := s.Err(); err != nil {
+		return err
+	}
+
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.routes = routes
+	return nil
+}
+
+func (c *Config) ReadFile(path string) error {
+	f, err := os.Open(path)
+	if err != nil {
+		return err
+	}
+	return c.Read(f)
+}