Allow setting listen address & read parameter from ENV

proxy/bird.go

@@ -0,0 +1,100 @@
+package main
+
+import (
+    "io"
+    "net"
+    "net/http"
+    "sync"
+)
+
+// BIRDv4 connection & mutex lock
+var bird net.Conn
+var birdMutex = &sync.Mutex{}
+
+// BIRDv6 connection & mutex lock
+var bird6 net.Conn
+var bird6Mutex = &sync.Mutex{}
+
+// Read a line from bird socket, removing preceding status number, output it.
+// Returns if there are more lines.
+func birdReadln(bird io.Reader, w io.Writer) bool {
+    // Read from socket byte by byte, until reaching newline character
+    c := make([]byte, 1024, 1024)
+    pos := 0
+    for {
+        if pos >= 1024 { break }
+        _, err := bird.Read(c[pos:pos+1])
+        if err != nil {
+            panic(err)
+        }
+        if c[pos] == byte('\n') {
+            break
+        }
+        pos++
+    }
+
+    c = c[:pos+1]
+    // print(string(c[:]))
+
+    // Remove preceding status number, different situations
+    if pos < 4 {
+        // Line is too short to have a status number
+        if w != nil {
+            pos = 0
+            for c[pos] == byte(' ') { pos++ }
+            w.Write(c[pos:])
+        }
+        return true
+    } else if isNumeric(c[0]) && isNumeric(c[1]) && isNumeric(c[2]) && isNumeric(c[3]) {
+        // There is a status number at beginning, remove first 5 bytes
+        if w != nil && pos > 6 {
+            pos = 5
+            for c[pos] == byte(' ') { pos++ }
+            w.Write(c[pos:])
+        }
+        return c[0] != byte('0') && c[0] != byte('8') && c[0] != byte('9')
+    } else {
+        // There is no status number, only remove preceding spaces
+        if w != nil {
+            pos = 0
+            for c[pos] == byte(' ') { pos++ }
+            w.Write(c[pos:])
+        }
+        return true
+    }
+}
+
+// Write a command to a bird socket
+func birdWriteln(bird io.Writer, s string) {
+    bird.Write([]byte(s + "\n"))
+}
+
+// Handles BIRDv4 queries
+func birdHandler(httpW http.ResponseWriter, httpR *http.Request) {
+    query := string(httpR.URL.Query().Get("q"))
+    if query == "" {
+        invalidHandler(httpW, httpR)
+    } else {
+        birdMutex.Lock()
+        defer birdMutex.Unlock()
+
+        println(query)
+        birdWriteln(bird, query)
+        for birdReadln(bird, httpW) {}
+    }
+}
+
+// Handles BIRDv6 queries
+func bird6Handler(httpW http.ResponseWriter, httpR *http.Request) {
+    query := string(httpR.URL.Query().Get("q"))
+    if query == "" {
+        invalidHandler(httpW, httpR)
+    } else {
+        bird6Mutex.Lock()
+        defer bird6Mutex.Unlock()
+
+        println(query)
+        birdWriteln(bird6, query)
+        for birdReadln(bird6, httpW) {}
+    }
+}