Merge branch 'udp' into develop

.gitignore

@@ -0,0 +1,2 @@
+/config.json
+/chihaya

Godeps/Godeps.json

@@ -1,10 +1,10 @@
 {
 	"ImportPath": "github.com/chihaya/chihaya",
-	"GoVersion": "go1.4.1",
+	"GoVersion": "go1.4.2",
 	"Deps": [
 		{
 			"ImportPath": "github.com/chihaya/bencode",
-			"Rev": "e60878f635e1a61315c413492e133dd39769b1d1"
+			"Rev": "3c485a8d166ff6a79baba90c2c2da01c8348e930"
 		},
 		{
 			"ImportPath": "github.com/golang/glog",
@@ -12,7 +12,11 @@
 		},
 		{
 			"ImportPath": "github.com/julienschmidt/httprouter",
-			"Rev": "00ce1c6a267162792c367acc43b1681a884e1872"
+			"Rev": "8c199fb6259ffc1af525cc3ad52ee60ba8359669"
+		},
+		{
+			"ImportPath": "github.com/pushrax/bufferpool",
+			"Rev": "7d6e1653dee10a165d1f357f3a57bc8031e9621b"
 		},
 		{
 			"ImportPath": "github.com/pushrax/faststats",
@@ -23,16 +27,13 @@
 			"Rev": "86044f1c998d49053e13293029414ddb63f3a422"
 		},
 		{
-			"ImportPath": "github.com/stretchr/graceful",
+			"ImportPath": "github.com/tylerb/graceful",
-			"Rev": "8e780ba3fe3d3e7ab15fc52e3d60a996587181dc"
+			"Comment": "v1-7-g0c01122",
-		},
+			"Rev": "0c011221e91b35f488b8818b00ca279929e9ed7d"
-		{
-			"ImportPath": "github.com/stretchr/pat/stop",
-			"Rev": "f7fe051f2b9bcaca162b38de4f93c9a8457160b9"
 		},
 		{
 			"ImportPath": "golang.org/x/net/netutil",
-			"Rev": "c84eff7014eba178f68bd4c05b86780efe0fbf35"
+			"Rev": "d175081df37eff8cda13f478bc11a0a65b39958b"
 		}
 	]
 }

Godeps/_workspace/src/github.com/chihaya/bencode/encoder.go

@@ -62,6 +62,12 @@ func marshal(w io.Writer, data interface{}) error {
 	case uint:
 		marshalUint(w, uint64(v))
 
+	case int16:
+		marshalInt(w, int64(v))
+
+	case uint16:
+		marshalUint(w, uint64(v))
+
 	case int64:
 		marshalInt(w, v)
 

Godeps/_workspace/src/github.com/chihaya/bencode/encoder_test.go

@@ -19,6 +19,8 @@ var marshalTests = []struct {
 	{uint(43), "i43e"},
 	{int64(44), "i44e"},
 	{uint64(45), "i45e"},
+	{int16(44), "i44e"},
+	{uint16(45), "i45e"},
 
 	{"example", "7:example"},
 	{[]byte("example"), "7:example"},

Godeps/_workspace/src/github.com/julienschmidt/httprouter/.travis.yml

@@ -1,3 +1,4 @@
+sudo: false
 language: go
 go:
   - 1.1

Godeps/_workspace/src/github.com/julienschmidt/httprouter/README.md

@@ -1,29 +1,17 @@
-# HttpRouter [![Build Status](https://travis-ci.org/julienschmidt/httprouter.png?branch=master)](https://travis-ci.org/julienschmidt/httprouter) [![GoDoc](http://godoc.org/github.com/julienschmidt/httprouter?status.png)](http://godoc.org/github.com/julienschmidt/httprouter)
+# HttpRouter [![Build Status](https://travis-ci.org/julienschmidt/httprouter.png?branch=master)](https://travis-ci.org/julienschmidt/httprouter) [![Coverage](http://gocover.io/_badge/github.com/julienschmidt/httprouter?0)](http://gocover.io/github.com/julienschmidt/httprouter) [![GoDoc](http://godoc.org/github.com/julienschmidt/httprouter?status.png)](http://godoc.org/github.com/julienschmidt/httprouter)
 
 HttpRouter is a lightweight high performance HTTP request router
 (also called *multiplexer* or just *mux* for short) for [Go](http://golang.org/).
 
-In contrast to the default mux of Go's net/http package, this router supports
+In contrast to the [default mux](http://golang.org/pkg/net/http/#ServeMux) of Go's net/http package, this router supports
 variables in the routing pattern and matches against the request method.
 It also scales better.
 
-The router is optimized for best performance and a small memory footprint.
+The router is optimized for high performance and a small memory footprint.
 It scales well even with very long paths and a large number of routes.
 A compressing dynamic trie (radix tree) structure is used for efficient matching.
 
 ## Features
-**Zero Garbage:** The matching and dispatching process generates zero bytes of
-garbage. In fact, the only heap allocations that are made, is by building the
-slice of the key-value pairs for path parameters. If the request path contains
-no parameters, not a single heap allocation is necessary.
-
-**Best Performance:** [Benchmarks speak for themselves](https://github.com/julienschmidt/go-http-routing-benchmark).
-See below for technical details of the implementation.
-
-**Parameters in your routing pattern:** Stop parsing the requested URL path,
-just give the path segment a name and the router delivers the dynamic value to
-you. Because of the design of the router, path parameters are very cheap.
-
 **Only explicit matches:** With other routers, like [http.ServeMux](http://golang.org/pkg/net/http/#ServeMux),
 a requested URL path could match multiple patterns. Therefore they have some
 awkward pattern priority rules, like *longest match* or *first registered,
@@ -34,7 +22,7 @@ great for SEO and improves the user experience.
 **Stop caring about trailing slashes:** Choose the URL style you like, the
 router automatically redirects the client if a trailing slash is missing or if
 there is one extra. Of course it only does so, if the new path has a handler.
-If you don't like it, you can turn off this behavior.
+If you don't like it, you can [turn off this behavior](http://godoc.org/github.com/julienschmidt/httprouter#Router.RedirectTrailingSlash).
 
 **Path auto-correction:** Besides detecting the missing or additional trailing
 slash at no extra cost, the router can also fix wrong cases and remove
@@ -43,11 +31,23 @@ Is [CAPTAIN CAPS LOCK](http://www.urbandictionary.com/define.php?term=Captain+Ca
 HttpRouter can help him by making a case-insensitive look-up and redirecting him
 to the correct URL.
 
-**No more server crashes:** You can set a PanicHandler to deal with panics
+**Parameters in your routing pattern:** Stop parsing the requested URL path,
+just give the path segment a name and the router delivers the dynamic value to
+you. Because of the design of the router, path parameters are very cheap.
+
+**Zero Garbage:** The matching and dispatching process generates zero bytes of
+garbage. In fact, the only heap allocations that are made, is by building the
+slice of the key-value pairs for path parameters. If the request path contains
+no parameters, not a single heap allocation is necessary.
+
+**Best Performance:** [Benchmarks speak for themselves](https://github.com/julienschmidt/go-http-routing-benchmark).
+See below for technical details of the implementation.
+
+**No more server crashes:** You can set a [Panic handler](http://godoc.org/github.com/julienschmidt/httprouter#Router.PanicHandler) to deal with panics
 occurring during handling a HTTP request. The router then recovers and lets the
 PanicHandler log what happened and deliver a nice error page.
 
-Of course you can also set a **custom NotFound handler** and **serve static files**.
+Of course you can also set **custom [NotFound](http://godoc.org/github.com/julienschmidt/httprouter#Router.NotFound) and  [MethodNotAllowed](http://godoc.org/github.com/julienschmidt/httprouter#Router.MethodNotAllowed) handlers** and [**serve static files**](http://godoc.org/github.com/julienschmidt/httprouter#Router.ServeFiles).
 
 ## Usage
 This is just a quick introduction, view the [GoDoc](http://godoc.org/github.com/julienschmidt/httprouter) for details.
@@ -189,7 +189,7 @@ for example the [Gorilla handlers](http://www.gorillatoolkit.org/pkg/handlers).
 Or you could [just write your own](http://justinas.org/writing-http-middleware-in-go/),
 it's very easy!
 
-Alternatively, you could try [a framework building upon HttpRouter](#web-frameworks--co-based-on-httprouter).
+Alternatively, you could try [a web framework based on HttpRouter](#web-frameworks-based-on-httprouter).
 
 ### Multi-domain / Sub-domains
 Here is a quick example: Does your server serve multiple domains / hosts?
@@ -256,7 +256,10 @@ func BasicAuth(h httprouter.Handle, user, pass []byte) httprouter.Handle {
 			payload, err := base64.StdEncoding.DecodeString(auth[len(basicAuthPrefix):])
 			if err == nil {
 				pair := bytes.SplitN(payload, []byte(":"), 2)
-				if len(pair) == 2 && bytes.Equal(pair[0], user) && bytes.Equal(pair[1], pass) {
+				if len(pair) == 2 &&
+					bytes.Equal(pair[0], user) &&
+					bytes.Equal(pair[1], pass) {
+
 					// Delegate request to the given handle
 					h(w, r, ps)
 					return
@@ -305,9 +308,16 @@ router.NotFound = http.FileServer(http.Dir("public")).ServeHTTP
 
 But this approach sidesteps the strict core rules of this router to avoid routing problems. A cleaner approach is to use a distinct sub-path for serving files, like `/static/*filepath` or `/files/*filepath`.
 
-## Web Frameworks & Co based on HttpRouter
+## Web Frameworks based on HttpRouter
 If the HttpRouter is a bit too minimalistic for you, you might try one of the following more high-level 3rd-party web frameworks building upon the HttpRouter package:
+* [Ace](https://github.com/plimble/ace): Blazing fast Go Web Framework
+* [api2go](https://github.com/univedo/api2go): A JSON API Implementation for Go
 * [Gin](https://github.com/gin-gonic/gin): Features a martini-like API with much better performance
+* [Goat](https://github.com/bahlo/goat): A minimalistic REST API server in Go
 * [Hikaru](https://github.com/najeira/hikaru): Supports standalone and Google AppEngine
 * [Hitch](https://github.com/nbio/hitch): Hitch ties httprouter, [httpcontext](https://github.com/nbio/httpcontext), and middleware up in a bow
+* [kami](https://github.com/guregu/kami): A tiny web framework using x/net/context
+* [Medeina](https://github.com/imdario/medeina): Inspired by Ruby's Roda and Cuba
 * [Neko](https://github.com/rocwong/neko): A lightweight web application framework for Golang
+* [Roxanna](https://github.com/iamthemuffinman/Roxanna): An amalgamation of httprouter, better logging, and hot reload
+* [siesta](https://github.com/VividCortex/siesta): Composable HTTP handlers with contexts

Godeps/_workspace/src/github.com/julienschmidt/httprouter/router.go

@@ -142,6 +142,11 @@ type Router struct {
 	// found. If it is not set, http.NotFound is used.
 	NotFound http.HandlerFunc
 
+	// Configurable http.HandlerFunc which is called when a request
+	// cannot be routed and HandleMethodNotAllowed is true.
+	// If it is not set, http.Error with http.StatusMethodNotAllowed is used.
+	MethodNotAllowed http.HandlerFunc
+
 	// Function to handle panics recovered from http handlers.
 	// It should be used to generate a error page and return the http error code
 	// 500 (Internal Server Error).
@@ -173,6 +178,11 @@ func (r *Router) HEAD(path string, handle Handle) {
 	r.Handle("HEAD", path, handle)
 }
 
+// OPTIONS is a shortcut for router.Handle("OPTIONS", path, handle)
+func (r *Router) OPTIONS(path string, handle Handle) {
+	r.Handle("OPTIONS", path, handle)
+}
+
 // POST is a shortcut for router.Handle("POST", path, handle)
 func (r *Router) POST(path string, handle Handle) {
 	r.Handle("POST", path, handle)
@@ -203,7 +213,7 @@ func (r *Router) DELETE(path string, handle Handle) {
 // communication with a proxy).
 func (r *Router) Handle(method, path string, handle Handle) {
 	if path[0] != '/' {
-		panic("path must begin with '/'")
+		panic("path must begin with '/' in path '" + path + "'")
 	}
 
 	if r.trees == nil {
@@ -232,11 +242,7 @@ func (r *Router) Handler(method, path string, handler http.Handler) {
 // HandlerFunc is an adapter which allows the usage of an http.HandlerFunc as a
 // request handle.
 func (r *Router) HandlerFunc(method, path string, handler http.HandlerFunc) {
-	r.Handle(method, path,
+	r.Handler(method, path, handler)
-		func(w http.ResponseWriter, req *http.Request, _ Params) {
-			handler(w, req)
-		},
-	)
 }
 
 // ServeFiles serves files from the given file system root.
@@ -251,7 +257,7 @@ func (r *Router) HandlerFunc(method, path string, handler http.HandlerFunc) {
 //     router.ServeFiles("/src/*filepath", http.Dir("/var/www"))
 func (r *Router) ServeFiles(path string, root http.FileSystem) {
 	if len(path) < 10 || path[len(path)-10:] != "/*filepath" {
-		panic("path must end with /*filepath")
+		panic("path must end with /*filepath in path '" + path + "'")
 	}
 
 	fileServer := http.FileServer(root)
@@ -335,10 +341,14 @@ func (r *Router) ServeHTTP(w http.ResponseWriter, req *http.Request) {
 
 			handle, _, _ := r.trees[method].getValue(req.URL.Path)
 			if handle != nil {
+				if r.MethodNotAllowed != nil {
+					r.MethodNotAllowed(w, req)
+				} else {
 					http.Error(w,
 						http.StatusText(http.StatusMethodNotAllowed),
 						http.StatusMethodNotAllowed,
 					)
+				}
 				return
 			}
 		}

Godeps/_workspace/src/github.com/julienschmidt/httprouter/router_test.go

@@ -76,7 +76,7 @@ func (h handlerStruct) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 }
 
 func TestRouterAPI(t *testing.T) {
-	var get, head, post, put, patch, delete, handler, handlerFunc bool
+	var get, head, options, post, put, patch, delete, handler, handlerFunc bool
 
 	httpHandler := handlerStruct{&handler}
 
@@ -87,6 +87,9 @@ func TestRouterAPI(t *testing.T) {
 	router.HEAD("/GET", func(w http.ResponseWriter, r *http.Request, _ Params) {
 		head = true
 	})
+	router.OPTIONS("/GET", func(w http.ResponseWriter, r *http.Request, _ Params) {
+		options = true
+	})
 	router.POST("/POST", func(w http.ResponseWriter, r *http.Request, _ Params) {
 		post = true
 	})
@@ -118,6 +121,12 @@ func TestRouterAPI(t *testing.T) {
 		t.Error("routing HEAD failed")
 	}
 
+	r, _ = http.NewRequest("OPTIONS", "/GET", nil)
+	router.ServeHTTP(w, r)
+	if !options {
+		t.Error("routing OPTIONS failed")
+	}
+
 	r, _ = http.NewRequest("POST", "/POST", nil)
 	router.ServeHTTP(w, r)
 	if !post {
@@ -176,7 +185,21 @@ func TestRouterNotAllowed(t *testing.T) {
 	w := httptest.NewRecorder()
 	router.ServeHTTP(w, r)
 	if !(w.Code == http.StatusMethodNotAllowed) {
-		t.Errorf("NotAllowed handling route %s failed: Code=%d, Header=%v", w.Code, w.Header())
+		t.Errorf("NotAllowed handling failed: Code=%d, Header=%v", w.Code, w.Header())
+	}
+
+	w = httptest.NewRecorder()
+	responseText := "custom method"
+	router.MethodNotAllowed = func(w http.ResponseWriter, req *http.Request) {
+		w.WriteHeader(http.StatusTeapot)
+		w.Write([]byte(responseText))
+	}
+	router.ServeHTTP(w, r)
+	if got := w.Body.String(); !(got == responseText) {
+		t.Errorf("unexpected response got %q want %q", got, responseText)
+	}
+	if w.Code != http.StatusTeapot {
+		t.Errorf("unexpected response code %d want %d", w.Code, http.StatusTeapot)
 	}
 }
 

Godeps/_workspace/src/github.com/julienschmidt/httprouter/tree.go

@@ -43,41 +43,48 @@ type node struct {
 	wildChild bool
 	nType     nodeType
 	maxParams uint8
-	indices   []byte
+	indices   string
 	children  []*node
 	handle    Handle
 	priority  uint32
 }
 
 // increments priority of the given child and reorders if necessary
-func (n *node) incrementChildPrio(i int) int {
+func (n *node) incrementChildPrio(pos int) int {
-	n.children[i].priority++
+	n.children[pos].priority++
-	prio := n.children[i].priority
+	prio := n.children[pos].priority
 
 	// adjust position (move to front)
-	for j := i - 1; j >= 0 && n.children[j].priority < prio; j-- {
+	newPos := pos
+	for newPos > 0 && n.children[newPos-1].priority < prio {
 		// swap node positions
-		tmpN := n.children[j]
+		tmpN := n.children[newPos-1]
-		n.children[j] = n.children[i]
+		n.children[newPos-1] = n.children[newPos]
-		n.children[i] = tmpN
+		n.children[newPos] = tmpN
-		tmpI := n.indices[j]
-		n.indices[j] = n.indices[i]
-		n.indices[i] = tmpI
 
-		i--
+		newPos--
 	}
-	return i
+
+	// build new index char string
+	if newPos != pos {
+		n.indices = n.indices[:newPos] + // unchanged prefix, might be empty
+			n.indices[pos:pos+1] + // the index char we move
+			n.indices[newPos:pos] + n.indices[pos+1:] // rest without char at 'pos'
+	}
+
+	return newPos
 }
 
 // addRoute adds a node with the given handle to the path.
 // Not concurrency-safe!
 func (n *node) addRoute(path string, handle Handle) {
+	fullPath := path
 	n.priority++
 	numParams := countParams(path)
 
 	// non-empty tree
 	if len(n.path) > 0 || len(n.children) > 0 {
-	WALK:
+	walk:
 		for {
 			// Update maxParams of the current node
 			if numParams > n.maxParams {
@@ -85,10 +92,12 @@ func (n *node) addRoute(path string, handle Handle) {
 			}
 
 			// Find the longest common prefix.
-			// This also implies that the commom prefix contains no ':' or '*'
+			// This also implies that the common prefix contains no ':' or '*'
-			// since the existing key can't contain this chars.
+			// since the existing key can't contain those chars.
 			i := 0
-			for max := min(len(path), len(n.path)); i < max && path[i] == n.path[i]; i++ {
+			max := min(len(path), len(n.path))
+			for i < max && path[i] == n.path[i] {
+				i++
 			}
 
 			// Split edge
@@ -110,7 +119,8 @@ func (n *node) addRoute(path string, handle Handle) {
 				}
 
 				n.children = []*node{&child}
-				n.indices = []byte{n.path[i]}
+				// []byte for proper unicode char conversion, see #65
+				n.indices = string([]byte{n.path[i]})
 				n.path = path[:i]
 				n.handle = nil
 				n.wildChild = false
@@ -134,11 +144,13 @@ func (n *node) addRoute(path string, handle Handle) {
 					if len(path) >= len(n.path) && n.path == path[:len(n.path)] {
 						// check for longer wildcard, e.g. :name and :names
 						if len(n.path) >= len(path) || path[len(n.path)] == '/' {
-							continue WALK
+							continue walk
 						}
 					}
 
-					panic("conflict with wildcard route")
+					panic("path segment '" + path +
+						"' conflicts with existing wildcard '" + n.path +
+						"' in path '" + fullPath + "'")
 				}
 
 				c := path[0]
@@ -147,21 +159,22 @@ func (n *node) addRoute(path string, handle Handle) {
 				if n.nType == param && c == '/' && len(n.children) == 1 {
 					n = n.children[0]
 					n.priority++
-					continue WALK
+					continue walk
 				}
 
 				// Check if a child with the next path byte exists
-				for i, index := range n.indices {
+				for i := 0; i < len(n.indices); i++ {
-					if c == index {
+					if c == n.indices[i] {
 						i = n.incrementChildPrio(i)
 						n = n.children[i]
-						continue WALK
+						continue walk
 					}
 				}
 
 				// Otherwise insert it
 				if c != ':' && c != '*' {
-					n.indices = append(n.indices, c)
+					// []byte for proper unicode char conversion, see #65
+					n.indices += string([]byte{c})
 					child := &node{
 						maxParams: numParams,
 					}
@@ -169,24 +182,24 @@ func (n *node) addRoute(path string, handle Handle) {
 					n.incrementChildPrio(len(n.indices) - 1)
 					n = child
 				}
-				n.insertChild(numParams, path, handle)
+				n.insertChild(numParams, path, fullPath, handle)
 				return
 
 			} else if i == len(path) { // Make node a (in-path) leaf
 				if n.handle != nil {
-					panic("a Handle is already registered for this path")
+					panic("a handle is already registered for path ''" + fullPath + "'")
 				}
 				n.handle = handle
 			}
 			return
 		}
 	} else { // Empty tree
-		n.insertChild(numParams, path, handle)
+		n.insertChild(numParams, path, fullPath, handle)
 	}
 }
 
-func (n *node) insertChild(numParams uint8, path string, handle Handle) {
+func (n *node) insertChild(numParams uint8, path, fullPath string, handle Handle) {
-	var offset int
+	var offset int // already handled bytes of the path
 
 	// find prefix until first wildcard (beginning with ':'' or '*'')
 	for i, max := 0, len(path); numParams > 0; i++ {
@@ -195,20 +208,29 @@ func (n *node) insertChild(numParams uint8, path string, handle Handle) {
 			continue
 		}
 
-		// Check if this Node existing children which would be
-		// unreachable if we insert the wildcard here
-		if len(n.children) > 0 {
-			panic("wildcard route conflicts with existing children")
-		}
-
 		// find wildcard end (either '/' or path end)
 		end := i + 1
 		for end < max && path[end] != '/' {
+			switch path[end] {
+			// the wildcard name must not contain ':' and '*'
+			case ':', '*':
+				panic("only one wildcard per path segment is allowed, has: '" +
+					path[i:] + "' in path '" + fullPath + "'")
+			default:
 				end++
 			}
+		}
 
+		// check if this Node existing children which would be
+		// unreachable if we insert the wildcard here
+		if len(n.children) > 0 {
+			panic("wildcard route '" + path[i:end] +
+				"' conflicts with existing children in path '" + fullPath + "'")
+		}
+
+		// check if the wildcard has a name
 		if end-i < 2 {
-			panic("wildcards must be named with a non-empty name")
+			panic("wildcards must be named with a non-empty name in path '" + fullPath + "'")
 		}
 
 		if c == ':' { // param
@@ -244,17 +266,17 @@ func (n *node) insertChild(numParams uint8, path string, handle Handle) {
 
 		} else { // catchAll
 			if end != max || numParams > 1 {
-				panic("catch-all routes are only allowed at the end of the path")
+				panic("catch-all routes are only allowed at the end of the path in path '" + fullPath + "'")
 			}
 
 			if len(n.path) > 0 && n.path[len(n.path)-1] == '/' {
-				panic("catch-all conflicts with existing handle for the path segment root")
+				panic("catch-all conflicts with existing handle for the path segment root in path '" + fullPath + "'")
 			}
 
 			// currently fixed width 1 for '/'
 			i--
 			if path[i] != '/' {
-				panic("no / before catch-all")
+				panic("no / before catch-all in path '" + fullPath + "'")
 			}
 
 			n.path = path[offset:i]
@@ -266,7 +288,7 @@ func (n *node) insertChild(numParams uint8, path string, handle Handle) {
 				maxParams: 1,
 			}
 			n.children = []*node{child}
-			n.indices = []byte{path[i]}
+			n.indices = string(path[i])
 			n = child
 			n.priority++
 
@@ -305,8 +327,8 @@ walk: // Outer loop for walking the tree
 				// to walk down the tree
 				if !n.wildChild {
 					c := path[0]
-					for i, index := range n.indices {
+					for i := 0; i < len(n.indices); i++ {
-						if c == index {
+						if c == n.indices[i] {
 							n = n.children[i]
 							continue walk
 						}
@@ -379,7 +401,7 @@ walk: // Outer loop for walking the tree
 					return
 
 				default:
-					panic("Invalid node type")
+					panic("invalid node type")
 				}
 			}
 		} else if path == n.path {
@@ -391,10 +413,10 @@ walk: // Outer loop for walking the tree
 
 			// No handle found. Check if a handle for this path + a
 			// trailing slash exists for trailing slash recommendation
-			for i, index := range n.indices {
+			for i := 0; i < len(n.indices); i++ {
-				if index == '/' {
+				if n.indices[i] == '/' {
 					n = n.children[i]
-					tsr = (n.path == "/" && n.handle != nil) ||
+					tsr = (len(n.path) == 1 && n.handle != nil) ||
 						(n.nType == catchAll && n.children[0].handle != nil)
 					return
 				}
@@ -414,7 +436,7 @@ walk: // Outer loop for walking the tree
 
 // Makes a case-insensitive lookup of the given path and tries to find a handler.
 // It can optionally also fix trailing slashes.
-// It returns the case-corrected path and a bool indicating wether the lookup
+// It returns the case-corrected path and a bool indicating whether the lookup
 // was successful.
 func (n *node) findCaseInsensitivePath(path string, fixTrailingSlash bool) (ciPath []byte, found bool) {
 	ciPath = make([]byte, 0, len(path)+1) // preallocate enough memory
@@ -433,7 +455,7 @@ func (n *node) findCaseInsensitivePath(path string, fixTrailingSlash bool) (ciPa
 				for i, index := range n.indices {
 					// must use recursive approach since both index and
 					// ToLower(index) could exist. We must check both.
-					if r == unicode.ToLower(rune(index)) {
+					if r == unicode.ToLower(index) {
 						out, found := n.children[i].findCaseInsensitivePath(path, fixTrailingSlash)
 						if found {
 							return append(ciPath, out...), true
@@ -445,10 +467,9 @@ func (n *node) findCaseInsensitivePath(path string, fixTrailingSlash bool) (ciPa
 				// without a trailing slash if a leaf exists for that path
 				found = (fixTrailingSlash && path == "/" && n.handle != nil)
 				return
+			}
 
-			} else {
 			n = n.children[0]
-
 			switch n.nType {
 			case param:
 				// find param end (either '/' or path end)
@@ -466,13 +487,14 @@ func (n *node) findCaseInsensitivePath(path string, fixTrailingSlash bool) (ciPa
 						path = path[k:]
 						n = n.children[0]
 						continue
-						} else { // ... but we can't
+					}
+
+					// ... but we can't
 					if fixTrailingSlash && len(path) == k+1 {
 						return ciPath, true
 					}
 					return
 				}
-					}
 
 				if n.handle != nil {
 					return ciPath, true
@@ -490,8 +512,7 @@ func (n *node) findCaseInsensitivePath(path string, fixTrailingSlash bool) (ciPa
 				return append(ciPath, path...), true
 
 			default:
-					panic("Invalid node type")
+				panic("invalid node type")
-				}
 			}
 		} else {
 			// We should have reached the node containing the handle.
@@ -503,10 +524,10 @@ func (n *node) findCaseInsensitivePath(path string, fixTrailingSlash bool) (ciPa
 			// No handle found.
 			// Try to fix the path by adding a trailing slash
 			if fixTrailingSlash {
-				for i, index := range n.indices {
+				for i := 0; i < len(n.indices); i++ {
-					if index == '/' {
+					if n.indices[i] == '/' {
 						n = n.children[i]
-						if (n.path == "/" && n.handle != nil) ||
+						if (len(n.path) == 1 && n.handle != nil) ||
 							(n.nType == catchAll && n.children[0].handle != nil) {
 							return append(ciPath, '/'), true
 						}

Godeps/_workspace/src/github.com/julienschmidt/httprouter/tree_test.go

@@ -125,6 +125,8 @@ func TestTreeAddAndGet(t *testing.T) {
 		"/doc/",
 		"/doc/go_faq.html",
 		"/doc/go1.html",
+		"/α",
+		"/β",
 	}
 	for _, route := range routes {
 		tree.addRoute(route, fakeHandler(route))
@@ -142,6 +144,8 @@ func TestTreeAddAndGet(t *testing.T) {
 		{"/cona", true, "", nil}, // key mismatch
 		{"/no", true, "", nil},   // no matching child
 		{"/ab", false, "/ab", nil},
+		{"/α", false, "/α", nil},
+		{"/β", false, "/β", nil},
 	})
 
 	checkPriorities(t, tree)
@@ -339,6 +343,27 @@ func TestTreeCatchAllConflictRoot(t *testing.T) {
 	testRoutes(t, routes)
 }
 
+func TestTreeDoubleWildcard(t *testing.T) {
+	const panicMsg = "only one wildcard per path segment is allowed"
+
+	routes := [...]string{
+		"/:foo:bar",
+		"/:foo:bar/",
+		"/:foo*bar",
+	}
+
+	for _, route := range routes {
+		tree := &node{}
+		recv := catchPanic(func() {
+			tree.addRoute(route, nil)
+		})
+
+		if rs, ok := recv.(string); !ok || !strings.HasPrefix(rs, panicMsg) {
+			t.Fatalf(`"Expected panic "%s" for route '%s', got "%v"`, panicMsg, route, recv)
+		}
+	}
+}
+
 /*func TestTreeDuplicateWildcard(t *testing.T) {
 	tree := &node{}
 
@@ -559,6 +584,8 @@ func TestTreeFindCaseInsensitivePath(t *testing.T) {
 }
 
 func TestTreeInvalidNodeType(t *testing.T) {
+	const panicMsg = "invalid node type"
+
 	tree := &node{}
 	tree.addRoute("/", fakeHandler("/"))
 	tree.addRoute("/:page", fakeHandler("/:page"))
@@ -570,15 +597,15 @@ func TestTreeInvalidNodeType(t *testing.T) {
 	recv := catchPanic(func() {
 		tree.getValue("/test")
 	})
-	if rs, ok := recv.(string); !ok || rs != "Invalid node type" {
+	if rs, ok := recv.(string); !ok || rs != panicMsg {
-		t.Fatalf(`Expected panic "Invalid node type", got "%v"`, recv)
+		t.Fatalf("Expected panic '"+panicMsg+"', got '%v'", recv)
 	}
 
 	// case-insensitive lookup
 	recv = catchPanic(func() {
 		tree.findCaseInsensitivePath("/test", true)
 	})
-	if rs, ok := recv.(string); !ok || rs != "Invalid node type" {
+	if rs, ok := recv.(string); !ok || rs != panicMsg {
-		t.Fatalf(`Expected panic "Invalid node type", got "%v"`, recv)
+		t.Fatalf("Expected panic '"+panicMsg+"', got '%v'", recv)
 	}
 }

Godeps/_workspace/src/github.com/pushrax/bufferpool/.travis.yml

@@ -0,0 +1 @@
+language: go

Godeps/_workspace/src/github.com/pushrax/bufferpool/AUTHORS

@@ -0,0 +1,4 @@
+# This is the official list of Bufferpool authors for copyright purposes.
+
+Jimmy Zelinskie <jimmyzelinskie@gmail.com>
+Justin Li <jli@j-li.net>

Godeps/_workspace/src/github.com/pushrax/bufferpool/LICENSE

@@ -0,0 +1,24 @@
+Bufferpool is released under a BSD 2-Clause license, reproduced below.
+
+Copyright (c) 2013, The Bufferpool Authors
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without modification,
+are permitted provided that the following conditions are met:
+
+    * Redistributions of source code must retain the above copyright notice,
+      this list of conditions and the following disclaimer.
+    * Redistributions in binary form must reproduce the above copyright notice,
+      this list of conditions and the following disclaimer in the documentation
+      and/or other materials provided with the distribution.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
+ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
+ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Godeps/_workspace/src/github.com/pushrax/bufferpool/README.md

@@ -0,0 +1,9 @@
+# bufferpool [![Build Status](https://secure.travis-ci.org/pushrax/bufferpool.png)](http://travis-ci.org/pushrax/bufferpool)
+
+The bufferpool package implements a thread-safe pool of reusable, equally sized `byte.Buffer`s.
+If you're allocating `byte.Buffer`s very frequently, you can use this to speed up your
+program and take strain off the garbage collector.
+
+## docs
+
+[GoDoc](http://godoc.org/github.com/pushrax/bufferpool)

Godeps/_workspace/src/github.com/pushrax/bufferpool/bufferpool.go

@@ -0,0 +1,69 @@
+// Copyright 2013 The Bufferpool Authors. All rights reserved.
+// Use of this source code is governed by the BSD 2-Clause license,
+// which can be found in the LICENSE file.
+
+// Package bufferpool implements a capacity-limited pool of reusable,
+// equally-sized buffers.
+package bufferpool
+
+import (
+	"bytes"
+	"errors"
+)
+
+// A BufferPool is a capacity-limited pool of equally sized buffers.
+type BufferPool struct {
+	bufferSize int
+	pool       chan []byte
+}
+
+// New returns a newly allocated BufferPool with the given maximum pool size
+// and buffer size.
+func New(poolSize, bufferSize int) *BufferPool {
+	return &BufferPool{
+		bufferSize,
+		make(chan []byte, poolSize),
+	}
+}
+
+// Take is used to obtain a new zeroed buffer. This will allocate a new buffer
+// if the pool was empty.
+func (pool *BufferPool) Take() *bytes.Buffer {
+	return bytes.NewBuffer(pool.TakeSlice()[:0])
+}
+
+// TakeSlice is used to obtain a new slice. This will allocate a new slice
+// if the pool was empty.
+func (pool *BufferPool) TakeSlice() (slice []byte) {
+	select {
+	case slice = <-pool.pool:
+	default:
+		slice = make([]byte, pool.bufferSize)
+	}
+	return
+}
+
+// Give is used to attempt to return a buffer to the pool. It may not
+// be added to the pool if it was already full.
+func (pool *BufferPool) Give(buf *bytes.Buffer) error {
+	buf.Reset()
+	slice := buf.Bytes()
+
+	if cap(slice) < pool.bufferSize {
+		return errors.New("Gave an incorrectly sized buffer to the pool.")
+	}
+
+	return pool.GiveSlice(slice[:buf.Len()])
+}
+
+// GiveSlice is used to attempt to return a slice to the pool. It may not
+// be added to the pool if it was already full.
+func (pool *BufferPool) GiveSlice(slice []byte) error {
+	select {
+	case pool.pool <- slice:
+		// Everything went smoothly!
+	default:
+		return errors.New("Gave a buffer to a full pool.")
+	}
+	return nil
+}

Godeps/_workspace/src/github.com/pushrax/bufferpool/bufferpool_test.go

@@ -0,0 +1,67 @@
+// Copyright 2013 The Bufferpool Authors. All rights reserved.
+// Use of this source code is governed by the BSD 2-Clause license,
+// which can be found in the LICENSE file.
+
+package bufferpool_test
+
+import (
+	"bytes"
+	"fmt"
+	"testing"
+
+	"github.com/pushrax/bufferpool"
+)
+
+func ExampleNew() {
+	bp := bufferpool.New(10, 255)
+
+	dogBuffer := bp.Take()
+	dogBuffer.WriteString("Dog!")
+	bp.Give(dogBuffer)
+
+	catBuffer := bp.Take() // dogBuffer is reused and reset.
+	catBuffer.WriteString("Cat!")
+
+	fmt.Println(catBuffer)
+	// Output:
+	// Cat!
+}
+
+func TestTakeFromEmpty(t *testing.T) {
+	bp := bufferpool.New(1, 1)
+	poolBuf := bp.Take()
+	if !bytes.Equal(poolBuf.Bytes(), []byte("")) {
+		t.Fatalf("Buffer from empty bufferpool was allocated incorrectly.")
+	}
+}
+
+func TestTakeFromFilled(t *testing.T) {
+	bp := bufferpool.New(1, 1)
+
+	origBuf := bytes.NewBuffer([]byte("X"))
+	bp.Give(origBuf)
+
+	reusedBuf := bp.Take()
+	if !bytes.Equal(reusedBuf.Bytes(), []byte("")) {
+		t.Fatalf("Buffer from filled bufferpool was recycled incorrectly.")
+	}
+
+	// Compare addresses of the first element in the underlying slice.
+	if &origBuf.Bytes()[:1][0] != &reusedBuf.Bytes()[:1][0] {
+		t.Fatalf("Recycled buffer points at different address.")
+	}
+}
+
+func TestSliceSemantics(t *testing.T) {
+	bp := bufferpool.New(1, 8)
+
+	buf := bp.Take()
+	buf.WriteString("abc")
+	bp.Give(buf)
+
+	buf2 := bp.TakeSlice()
+
+	if !bytes.Equal(buf2[:3], []byte("abc")) {
+		t.Fatalf("Buffer from filled bufferpool was recycled incorrectly.")
+	}
+}

Godeps/_workspace/src/github.com/stretchr/graceful/wercker.yml

@@ -1 +0,0 @@
-box: wercker/golang

Godeps/_workspace/src/github.com/stretchr/pat/stop/doc.go

@@ -1,46 +0,0 @@
-// Package stop represents a pattern for types that need to do some work
-// when stopping. The StopChan method returns a <-chan stop.Signal which
-// is closed when the operation has completed.
-//
-// Stopper types when implementing the stop channel pattern should use stop.Make
-// to create and store a stop channel, and close the channel once stopping has completed:
-//     func New() Type {
-//       t := new(Type)
-//       t.stopChan = stop.Make()
-//       return t
-//     }
-//     func (t Type) Stop() {
-//       go func(){
-//         // TODO: tear stuff down
-//         close(t.stopChan)
-//       }()
-//     }
-//     func (t Type) StopChan() <-chan stop.Signal {
-//       return t.stopChan
-//     }
-//
-// Stopper types can be stopped in the following ways:
-//     // stop and forget
-//     t.Stop(1 * time.Second)
-//
-//     // stop and wait
-//     t.Stop(1 * time.Second)
-//     <-t.StopChan()
-//
-//     // stop, do more work, then wait
-//     t.Stop(1 * time.Second);
-//     // do more work
-//     <-t.StopChan()
-//
-//     // stop and timeout after 1 second
-//     t.Stop(1 * time.Second)
-//     select {
-//     case <-t.StopChan():
-//     case <-time.After(1 * time.Second):
-//     }
-//
-//     // stop.All is the same as calling Stop() then StopChan() so
-//     // all above patterns also work on many Stopper types,
-//     // for example; stop and wait for many things:
-//     <-stop.All(1 * time.Second, t1, t2, t3)
-package stop

Godeps/_workspace/src/github.com/stretchr/pat/stop/stop.go

@@ -1,57 +0,0 @@
-package stop
-
-import "time"
-
-// Signal is the type that gets sent down the stop channel.
-type Signal struct{}
-
-// NoWait represents a time.Duration with zero value.
-// Logically meaning no grace wait period when stopping.
-var NoWait time.Duration
-
-// Stopper represents types that implement
-// the stop channel pattern.
-type Stopper interface {
-	// Stop instructs the type to halt operations and close
-	// the stop channel when it is finished.
-	Stop(wait time.Duration)
-	// StopChan gets the stop channel which will block until
-	// stopping has completed, at which point it is closed.
-	// Callers should never close the stop channel.
-	// The StopChan should exist from the point at which operations
-	// begun, not the point at which Stop was called.
-	StopChan() <-chan Signal
-}
-
-// Stopped returns a channel that signals immediately. Useful for
-// cases when no tear-down work is required and stopping is
-// immediate.
-func Stopped() <-chan Signal {
-	c := Make()
-	close(c)
-	return c
-}
-
-// Make makes a new channel used to indicate when
-// stopping has finished. Sends to channel will not block.
-func Make() chan Signal {
-	return make(chan Signal, 0)
-}
-
-// All stops all Stopper types and returns another channel
-// which will close once all things have finished stopping.
-func All(wait time.Duration, stoppers ...Stopper) <-chan Signal {
-	all := Make()
-	go func() {
-		var allChans []<-chan Signal
-		for _, stopper := range stoppers {
-			go stopper.Stop(wait)
-			allChans = append(allChans, stopper.StopChan())
-		}
-		for _, ch := range allChans {
-			<-ch
-		}
-		close(all)
-	}()
-	return all
-}

Godeps/_workspace/src/github.com/stretchr/pat/stop/stop_test.go

@@ -1,76 +0,0 @@
-package stop_test
-
-import (
-	"testing"
-	"time"
-
-	"github.com/stretchr/pat/stop"
-)
-
-type testStopper struct {
-	stopChan chan stop.Signal
-}
-
-func NewTestStopper() *testStopper {
-	s := new(testStopper)
-	s.stopChan = stop.Make()
-	return s
-}
-
-func (t *testStopper) Stop(wait time.Duration) {
-	go func() {
-		time.Sleep(100 * time.Millisecond)
-		close(t.stopChan)
-	}()
-}
-func (t *testStopper) StopChan() <-chan stop.Signal {
-	return t.stopChan
-}
-
-type noopStopper struct{}
-
-func (t *noopStopper) Stop() {
-}
-func (t *noopStopper) StopChan() <-chan stop.Signal {
-	return stop.Stopped()
-}
-
-func TestStop(t *testing.T) {
-
-	s := NewTestStopper()
-	s.Stop(1 * time.Second)
-	stopChan := s.StopChan()
-	select {
-	case <-stopChan:
-	case <-time.After(1 * time.Second):
-		t.Error("Stop signal was never sent (timed out)")
-	}
-
-}
-
-func TestAll(t *testing.T) {
-
-	s1 := NewTestStopper()
-	s2 := NewTestStopper()
-	s3 := NewTestStopper()
-
-	select {
-	case <-stop.All(1*time.Second, s1, s2, s3):
-	case <-time.After(1 * time.Second):
-		t.Error("All signal was never sent (timed out)")
-	}
-
-}
-
-func TestNoop(t *testing.T) {
-
-	s := new(noopStopper)
-	s.Stop()
-	stopChan := s.StopChan()
-	select {
-	case <-stopChan:
-	case <-time.After(1 * time.Second):
-		t.Error("Stop signal was never sent (timed out)")
-	}
-
-}

Godeps/_workspace/src/github.com/tylerb/graceful/LICENSE

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2014 Stretchr, Inc.
+Copyright (c) 2014 Tyler Bunnell
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

Godeps/_workspace/src/github.com/tylerb/graceful/README.md

@@ -1,17 +1,30 @@
-graceful [![GoDoc](https://godoc.org/github.com/stretchr/graceful?status.png)](http://godoc.org/github.com/stretchr/graceful) [![wercker status](https://app.wercker.com/status/2729ba763abf87695a17547e0f7af4a4/s "wercker status")](https://app.wercker.com/project/bykey/2729ba763abf87695a17547e0f7af4a4)
+graceful [![GoDoc](https://godoc.org/github.com/tylerb/graceful?status.png)](http://godoc.org/github.com/tylerb/graceful) [![Build Status](https://drone.io/github.com/tylerb/graceful/status.png)](https://drone.io/github.com/tylerb/graceful/latest) [![Coverage Status](https://coveralls.io/repos/tylerb/graceful/badge.svg?branch=dronedebug)](https://coveralls.io/r/tylerb/graceful?branch=dronedebug) [![Gitter](https://badges.gitter.im/Join%20Chat.svg)](https://gitter.im/tylerb/graceful?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge)
 ========
 
 Graceful is a Go 1.3+ package enabling graceful shutdown of http.Handler servers.
 
+## Installation
+
+To install, simply execute:
+
+```
+go get gopkg.in/tylerb/graceful.v1
+```
+
+I am using [gopkg.in](http://http://labix.org/gopkg.in) to control releases.
+
 ## Usage
 
-Usage of Graceful is simple. Create your http.Handler and pass it to the `Run` function:
+Using Graceful is easy. Simply create your http.Handler and pass it to the `Run` function:
 
 ```go
+package main
+
 import (
-  "github.com/stretchr/graceful"
+  "gopkg.in/tylerb/graceful.v1"
   "net/http"
   "fmt"
+  "time"
 )
 
 func main() {
@@ -31,9 +44,10 @@ package main
 
 import (
   "github.com/codegangsta/negroni"
-  "github.com/stretchr/graceful"
+  "gopkg.in/tylerb/graceful.v1"
   "net/http"
   "fmt"
+  "time"
 )
 
 func main() {
@@ -111,4 +125,13 @@ same time and all will be signalled when stopping is complete.
 
 ## Contributing
 
-Before sending a pull request, please open a new issue describing the feature/issue you wish to address so it can be discussed. The subsequent pull request should close that issue.
+If you would like to contribute, please:
+
+1. Create a GitHub issue regarding the contribution. Features and bugs should be discussed beforehand.
+2. Fork the repository.
+3. Create a pull request with your solution. This pull request should reference and close the issues (Fix #2).
+
+All pull requests should:
+
+1. Pass [gometalinter -t .](https://github.com/alecthomas/gometalinter) with no warnings.
+2. Be `go fmt` formatted.

Godeps/_workspace/src/github.com/tylerb/graceful/graceful.go

@@ -11,7 +11,6 @@ import (
 	"syscall"
 	"time"
 
-	"github.com/stretchr/pat/stop"
 	"golang.org/x/net/netutil"
 )
 
@@ -46,25 +45,26 @@ type Server struct {
 	// side of long lived connections (e.g. websockets) to reconnect.
 	ShutdownInitiated func()
 
+	// NoSignalHandling prevents graceful from automatically shutting down
+	// on SIGINT and SIGTERM. If set to true, you must shut down the server
+	// manually with Stop().
+	NoSignalHandling bool
+
 	// interrupt signals the listener to stop serving connections,
 	// and the server to shut down.
 	interrupt chan os.Signal
 
 	// stopChan is the channel on which callers may block while waiting for
 	// the server to stop.
-	stopChan chan stop.Signal
+	stopChan chan struct{}
 
-	// stopChanOnce is used to create the stop channel on demand, once, per
+	// stopLock is used to protect access to the stopChan.
-	// instance.
+	stopLock sync.RWMutex
-	stopChanOnce sync.Once
 
 	// connections holds all connections managed by graceful
 	connections map[net.Conn]struct{}
 }
 
-// ensure Server conforms to stop.Stopper
-var _ stop.Stopper = (*Server)(nil)
-
 // Run serves the http.Handler with graceful shutdown enabled.
 //
 // timeout is the duration to wait until killing active requests and stopping the server.
@@ -173,7 +173,6 @@ func (srv *Server) Serve(listener net.Listener) error {
 		case http.StateClosed, http.StateHijacked:
 			remove <- conn
 		}
-
 		if srv.ConnState != nil {
 			srv.ConnState(conn, state)
 		}
@@ -182,7 +181,53 @@ func (srv *Server) Serve(listener net.Listener) error {
 	// Manage open connections
 	shutdown := make(chan chan struct{})
 	kill := make(chan struct{})
-	go func() {
+	go srv.manageConnections(add, remove, shutdown, kill)
+
+	interrupt := srv.interruptChan()
+
+	// Set up the interrupt handler
+	if !srv.NoSignalHandling {
+		signal.Notify(interrupt, syscall.SIGINT, syscall.SIGTERM)
+	}
+
+	go srv.handleInterrupt(interrupt, listener)
+
+	// Serve with graceful listener.
+	// Execution blocks here until listener.Close() is called, above.
+	err := srv.Server.Serve(listener)
+
+	srv.shutdown(shutdown, kill)
+
+	return err
+}
+
+// Stop instructs the type to halt operations and close
+// the stop channel when it is finished.
+//
+// timeout is grace period for which to wait before shutting
+// down the server. The timeout value passed here will override the
+// timeout given when constructing the server, as this is an explicit
+// command to stop the server.
+func (srv *Server) Stop(timeout time.Duration) {
+	srv.Timeout = timeout
+	interrupt := srv.interruptChan()
+	interrupt <- syscall.SIGINT
+}
+
+// StopChan gets the stop channel which will block until
+// stopping has completed, at which point it is closed.
+// Callers should never close the stop channel.
+func (srv *Server) StopChan() <-chan struct{} {
+	srv.stopLock.Lock()
+	if srv.stopChan == nil {
+		srv.stopChan = make(chan struct{})
+	}
+	srv.stopLock.Unlock()
+	return srv.stopChan
+}
+
+func (srv *Server) manageConnections(add, remove chan net.Conn, shutdown chan chan struct{}, kill chan struct{}) {
+	{
 		var done chan struct{}
 		srv.connections = map[net.Conn]struct{}{}
 		for {
@@ -202,36 +247,39 @@ func (srv *Server) Serve(listener net.Listener) error {
 				}
 			case <-kill:
 				for k := range srv.connections {
-					k.Close()
+					_ = k.Close() // nothing to do here if it errors
 				}
 				return
 			}
 		}
-	}()
+	}
+}
 
+func (srv *Server) interruptChan() chan os.Signal {
+	srv.stopLock.Lock()
 	if srv.interrupt == nil {
 		srv.interrupt = make(chan os.Signal, 1)
 	}
+	srv.stopLock.Unlock()
+
+	return srv.interrupt
+}
+
+func (srv *Server) handleInterrupt(interrupt chan os.Signal, listener net.Listener) {
+	<-interrupt
 
-	// Set up the interrupt catch
-	signal.Notify(srv.interrupt, syscall.SIGINT, syscall.SIGTERM)
-	go func() {
-		<-srv.interrupt
 	srv.SetKeepAlivesEnabled(false)
-		listener.Close()
+	_ = listener.Close() // we are shutting down anyway. ignore error.
 
 	if srv.ShutdownInitiated != nil {
 		srv.ShutdownInitiated()
 	}
 
-		signal.Stop(srv.interrupt)
+	signal.Stop(interrupt)
-		close(srv.interrupt)
+	close(interrupt)
-	}()
+}
-
-	// Serve with graceful listener.
-	// Execution blocks here until listener.Close() is called, above.
-	err := srv.Server.Serve(listener)
 
+func (srv *Server) shutdown(shutdown chan chan struct{}, kill chan struct{}) {
 	// Request done notification
 	done := make(chan struct{})
 	shutdown <- done
@@ -246,32 +294,9 @@ func (srv *Server) Serve(listener net.Listener) error {
 		<-done
 	}
 	// Close the stopChan to wake up any blocked goroutines.
+	srv.stopLock.Lock()
 	if srv.stopChan != nil {
 		close(srv.stopChan)
 	}
-	return err
+	srv.stopLock.Unlock()
-}
-
-// Stop instructs the type to halt operations and close
-// the stop channel when it is finished.
-//
-// timeout is grace period for which to wait before shutting
-// down the server. The timeout value passed here will override the
-// timeout given when constructing the server, as this is an explicit
-// command to stop the server.
-func (srv *Server) Stop(timeout time.Duration) {
-	srv.Timeout = timeout
-	srv.interrupt <- syscall.SIGINT
-}
-
-// StopChan gets the stop channel which will block until
-// stopping has completed, at which point it is closed.
-// Callers should never close the stop channel.
-func (srv *Server) StopChan() <-chan stop.Signal {
-	srv.stopChanOnce.Do(func() {
-		if srv.stopChan == nil {
-			srv.stopChan = stop.Make()
-		}
-	})
-	return srv.stopChan
 }

Godeps/_workspace/src/github.com/tylerb/graceful/graceful_test.go

@@ -1,6 +1,7 @@
 package graceful
 
 import (
+	"fmt"
 	"io"
 	"net"
 	"net/http"
@@ -13,32 +14,50 @@ import (
 	"time"
 )
 
-var killTime = 50 * time.Millisecond
+var (
+	killTime    = 500 * time.Millisecond
+	timeoutTime = 1000 * time.Millisecond
+	waitTime    = 100 * time.Millisecond
+)
 
-func runQuery(t *testing.T, expected int, shouldErr bool, wg *sync.WaitGroup) {
+func runQuery(t *testing.T, expected int, shouldErr bool, wg *sync.WaitGroup, once *sync.Once) {
 	wg.Add(1)
 	defer wg.Done()
 	client := http.Client{}
 	r, err := client.Get("http://localhost:3000")
 	if shouldErr && err == nil {
+		once.Do(func() {
 			t.Fatal("Expected an error but none was encountered.")
+		})
 	} else if shouldErr && err != nil {
-		if err.(*url.Error).Err == io.EOF {
+		if checkErr(t, err, once) {
 			return
 		}
-		errno := err.(*url.Error).Err.(*net.OpError).Err.(syscall.Errno)
+	}
-		if errno == syscall.ECONNREFUSED {
+	if r != nil && r.StatusCode != expected {
-			return
+		once.Do(func() {
-		} else if err != nil {
+			t.Fatalf("Incorrect status code on response. Expected %d. Got %d", expected, r.StatusCode)
-			t.Fatal("Error on Get:", err)
+		})
+	} else if r == nil {
+		once.Do(func() {
+			t.Fatal("No response when a response was expected.")
+		})
 	}
 }
 
-	if r != nil && r.StatusCode != expected {
+func checkErr(t *testing.T, err error, once *sync.Once) bool {
-		t.Fatalf("Incorrect status code on response. Expected %d. Got %d", expected, r.StatusCode)
+	if err.(*url.Error).Err == io.EOF {
-	} else if r == nil {
+		return true
-		t.Fatal("No response when a response was expected.")
 	}
+	errno := err.(*url.Error).Err.(*net.OpError).Err.(syscall.Errno)
+	if errno == syscall.ECONNREFUSED {
+		return true
+	} else if err != nil {
+		once.Do(func() {
+			t.Fatal("Error on Get:", err)
+		})
+	}
+	return false
 }
 
 func createListener(sleep time.Duration) (*http.Server, net.Listener, error) {
@@ -50,6 +69,9 @@ func createListener(sleep time.Duration) (*http.Server, net.Listener, error) {
 
 	server := &http.Server{Addr: ":3000", Handler: mux}
 	l, err := net.Listen("tcp", ":3000")
+	if err != nil {
+		fmt.Println(err)
+	}
 	return server, l, err
 }
 
@@ -64,16 +86,17 @@ func runServer(timeout, sleep time.Duration, c chan os.Signal) error {
 }
 
 func launchTestQueries(t *testing.T, wg *sync.WaitGroup, c chan os.Signal) {
+	var once sync.Once
 	for i := 0; i < 8; i++ {
-		go runQuery(t, http.StatusOK, false, wg)
+		go runQuery(t, http.StatusOK, false, wg, &once)
 	}
 
-	time.Sleep(10 * time.Millisecond)
+	time.Sleep(waitTime)
 	c <- os.Interrupt
-	time.Sleep(10 * time.Millisecond)
+	time.Sleep(waitTime)
 
 	for i := 0; i < 8; i++ {
-		go runQuery(t, 0, true, wg)
+		go runQuery(t, 0, true, wg, &once)
 	}
 
 	wg.Done()
@@ -106,16 +129,17 @@ func TestGracefulRunTimesOut(t *testing.T) {
 		wg.Done()
 	}()
 
+	var once sync.Once
 	wg.Add(1)
 	go func() {
 		for i := 0; i < 8; i++ {
-			go runQuery(t, 0, true, &wg)
+			go runQuery(t, 0, true, &wg, &once)
 		}
-		time.Sleep(10 * time.Millisecond)
+		time.Sleep(waitTime)
 		c <- os.Interrupt
-		time.Sleep(10 * time.Millisecond)
+		time.Sleep(waitTime)
 		for i := 0; i < 8; i++ {
-			go runQuery(t, 0, true, &wg)
+			go runQuery(t, 0, true, &wg, &once)
 		}
 		wg.Done()
 	}()
@@ -160,14 +184,23 @@ func TestGracefulRunNoRequests(t *testing.T) {
 func TestGracefulForwardsConnState(t *testing.T) {
 	c := make(chan os.Signal, 1)
 	states := make(map[http.ConnState]int)
+	var stateLock sync.Mutex
 
 	connState := func(conn net.Conn, state http.ConnState) {
+		stateLock.Lock()
 		states[state]++
+		stateLock.Unlock()
 	}
 
 	var wg sync.WaitGroup
 	wg.Add(1)
 
+	expected := map[http.ConnState]int{
+		http.StateNew:    8,
+		http.StateActive: 8,
+		http.StateClosed: 8,
+	}
+
 	go func() {
 		server, l, _ := createListener(killTime / 2)
 		srv := &Server{
@@ -185,15 +218,11 @@ func TestGracefulForwardsConnState(t *testing.T) {
 	go launchTestQueries(t, &wg, c)
 	wg.Wait()
 
-	expected := map[http.ConnState]int{
+	stateLock.Lock()
-		http.StateNew:    8,
-		http.StateActive: 8,
-		http.StateClosed: 8,
-	}
-
 	if !reflect.DeepEqual(states, expected) {
 		t.Errorf("Incorrect connection state tracking.\n  actual: %v\nexpected: %v\n", states, expected)
 	}
+	stateLock.Unlock()
 }
 
 func TestGracefulExplicitStop(t *testing.T) {
@@ -206,14 +235,14 @@ func TestGracefulExplicitStop(t *testing.T) {
 
 	go func() {
 		go srv.Serve(l)
-		time.Sleep(10 * time.Millisecond)
+		time.Sleep(waitTime)
 		srv.Stop(killTime)
 	}()
 
 	// block on the stopChan until the server has shut down
 	select {
 	case <-srv.StopChan():
-	case <-time.After(100 * time.Millisecond):
+	case <-time.After(timeoutTime):
 		t.Fatal("Timed out while waiting for explicit stop to complete")
 	}
 }
@@ -228,7 +257,7 @@ func TestGracefulExplicitStopOverride(t *testing.T) {
 
 	go func() {
 		go srv.Serve(l)
-		time.Sleep(10 * time.Millisecond)
+		time.Sleep(waitTime)
 		srv.Stop(killTime / 2)
 	}()
 
@@ -253,7 +282,7 @@ func TestShutdownInitiatedCallback(t *testing.T) {
 
 	go func() {
 		go srv.Serve(l)
-		time.Sleep(10 * time.Millisecond)
+		time.Sleep(waitTime)
 		srv.Stop(killTime)
 	}()
 
@@ -302,12 +331,9 @@ func TestNotifyClosed(t *testing.T) {
 		wg.Done()
 	}()
 
+	var once sync.Once
 	for i := 0; i < 8; i++ {
-		runQuery(t, http.StatusOK, false, &wg)
+		runQuery(t, http.StatusOK, false, &wg, &once)
-	}
-
-	if len(srv.connections) > 0 {
-		t.Fatal("hijacked connections should not be managed")
 	}
 
 	srv.Stop(0)
@@ -315,8 +341,39 @@ func TestNotifyClosed(t *testing.T) {
 	// block on the stopChan until the server has shut down
 	select {
 	case <-srv.StopChan():
-	case <-time.After(100 * time.Millisecond):
+	case <-time.After(timeoutTime):
 		t.Fatal("Timed out while waiting for explicit stop to complete")
 	}
 
+	if len(srv.connections) > 0 {
+		t.Fatal("hijacked connections should not be managed")
+	}
+
+}
+
+func TestStopDeadlock(t *testing.T) {
+	c := make(chan struct{})
+
+	server, l, err := createListener(1 * time.Millisecond)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	srv := &Server{Server: server, NoSignalHandling: true}
+
+	go func() {
+		time.Sleep(waitTime)
+		srv.Serve(l)
+	}()
+
+	go func() {
+		srv.Stop(0)
+		close(c)
+	}()
+
+	select {
+	case <-c:
+	case <-time.After(timeoutTime):
+		t.Fatal("Timed out while waiting for explicit stop to complete")
+	}
 }

Godeps/_workspace/src/github.com/tylerb/graceful/tests/main.go

@@ -5,7 +5,7 @@ import (
 	"sync"
 
 	"github.com/codegangsta/negroni"
-	"github.com/stretchr/graceful"
+	"github.com/tylerb/graceful"
 )
 
 func main() {

chihaya.go

@@ -7,8 +7,11 @@ package chihaya
 import (
 	"flag"
 	"os"
+	"os/signal"
 	"runtime"
 	"runtime/pprof"
+	"sync"
+	"syscall"
 
 	"github.com/golang/glog"
 
@@ -16,6 +19,7 @@ import (
 	"github.com/chihaya/chihaya/http"
 	"github.com/chihaya/chihaya/stats"
 	"github.com/chihaya/chihaya/tracker"
+	"github.com/chihaya/chihaya/udp"
 
 	// See the README for how to import custom drivers.
 	_ "github.com/chihaya/chihaya/backend/noop"
@@ -77,6 +81,50 @@ func Boot() {
 		glog.Fatal("New: ", err)
 	}
 
-	http.Serve(cfg, tkr)
+	var wg sync.WaitGroup
-	glog.Info("Gracefully shut down")
+	var servers []tracker.Server
+
+	if cfg.HTTPListenAddr != "" {
+		wg.Add(1)
+		srv := http.NewServer(cfg, tkr)
+		servers = append(servers, srv)
+
+		go func() {
+			defer wg.Done()
+			srv.Serve(cfg.HTTPListenAddr)
+		}()
+	}
+
+	if cfg.UDPListenAddr != "" {
+		wg.Add(1)
+		srv := udp.NewServer(cfg, tkr)
+		servers = append(servers, srv)
+
+		go func() {
+			defer wg.Done()
+			srv.Serve(cfg.UDPListenAddr)
+		}()
+	}
+
+	shutdown := make(chan os.Signal)
+	signal.Notify(shutdown, syscall.SIGINT, syscall.SIGTERM)
+
+	go func() {
+		wg.Wait()
+		signal.Stop(shutdown)
+		close(shutdown)
+	}()
+
+	<-shutdown
+	glog.Info("Shutting down...")
+
+	for _, srv := range servers {
+		srv.Stop()
+	}
+
+	<-shutdown
+
+	if err := tkr.Close(); err != nil {
+		glog.Errorf("Failed to shut down tracker cleanly: %s", err.Error())
+	}
 }

config/config.go

@@ -90,17 +90,24 @@ type TrackerConfig struct {
 
 // HTTPConfig is the configuration for HTTP functionality.
 type HTTPConfig struct {
-	ListenAddr       string   `json:"http_listen_addr"`
+	HTTPListenAddr     string   `json:"http_listen_addr"`
-	RequestTimeout   Duration `json:"http_request_timeout"`
+	HTTPRequestTimeout Duration `json:"http_request_timeout"`
 	HTTPReadTimeout    Duration `json:"http_read_timeout"`
 	HTTPWriteTimeout   Duration `json:"http_write_timeout"`
 	HTTPListenLimit    int      `json:"http_listen_limit"`
 }
 
+// UDPConfig is the configuration for HTTP functionality.
+type UDPConfig struct {
+	UDPListenAddr     string `json:"udp_listen_addr"`
+	UDPReadBufferSize int    `json:"udp_read_buffer_size"`
+}
+
 // Config is the global configuration for an instance of Chihaya.
 type Config struct {
 	TrackerConfig
 	HTTPConfig
+	UDPConfig
 	DriverConfig
 	StatsConfig
 }
@@ -129,12 +136,16 @@ var DefaultConfig = Config{
 	},
 
 	HTTPConfig: HTTPConfig{
-		ListenAddr:       ":6881",
+		HTTPListenAddr:     ":6881",
-		RequestTimeout:   Duration{10 * time.Second},
+		HTTPRequestTimeout: Duration{10 * time.Second},
 		HTTPReadTimeout:    Duration{10 * time.Second},
 		HTTPWriteTimeout:   Duration{10 * time.Second},
 	},
 
+	UDPConfig: UDPConfig{
+		UDPListenAddr: ":6882",
+	},
+
 	DriverConfig: DriverConfig{
 		Name: "noop",
 	},

example_config.json

@@ -13,10 +13,11 @@
   "respect_af": false,
   "client_whitelist_enabled": false,
   "client_whitelist": ["OP1011"],
+  "udp_listen_addr": ":6881",
   "http_listen_addr": ":6881",
-  "http_request_timeout": "10s",
+  "http_request_timeout": "4s",
-  "http_read_timeout": "10s",
+  "http_read_timeout": "4s",
-  "http_write_timeout": "10s",
+  "http_write_timeout": "4s",
   "http_listen_limit": 0,
   "driver": "noop",
   "stats_buffer_size": 0,

http/announce_test.go

@@ -31,10 +31,10 @@ func TestPublicAnnounce(t *testing.T) {
 	peer3 := makePeerParams("peer3", false)
 
 	peer1["event"] = "started"
-	expected := makeResponse(1, 0)
+	expected := makeResponse(1, 0, peer1)
 	checkAnnounce(peer1, expected, srv, t)
 
-	expected = makeResponse(2, 0)
+	expected = makeResponse(2, 0, peer2)
 	checkAnnounce(peer2, expected, srv, t)
 
 	expected = makeResponse(2, 1, peer1, peer2)
@@ -147,7 +147,7 @@ func TestPrivateAnnounce(t *testing.T) {
 	peer2 := makePeerParams("-TR2820-peer2", false)
 	peer3 := makePeerParams("-TR2820-peer3", true)
 
-	expected := makeResponse(0, 1)
+	expected := makeResponse(0, 1, peer1)
 	srv.URL = baseURL + "/users/vvvvvvvvvvvvvvvvvvvvvvvvvvvvvvv1"
 	checkAnnounce(peer1, expected, srv, t)
 
@@ -189,7 +189,7 @@ func TestPreferredSubnet(t *testing.T) {
 	peerD1 := makePeerParams("peerD1", false, "fc02::1")
 	peerD2 := makePeerParams("peerD2", false, "fc02::2")
 
-	expected := makeResponse(0, 1)
+	expected := makeResponse(0, 1, peerA1)
 	checkAnnounce(peerA1, expected, srv, t)
 
 	expected = makeResponse(0, 2, peerA1)
@@ -255,7 +255,7 @@ func TestCompactAnnounce(t *testing.T) {
 	peer3["compact"] = "1"
 
 	expected := makeResponse(0, 1)
-	expected["peers"] = ""
+	expected["peers"] = compact
 	checkAnnounce(peer1, expected, srv, t)
 
 	expected = makeResponse(0, 2)

http/http.go

@@ -12,7 +12,7 @@ import (
 
 	"github.com/golang/glog"
 	"github.com/julienschmidt/httprouter"
-	"github.com/stretchr/graceful"
+	"github.com/tylerb/graceful"
 
 	"github.com/chihaya/chihaya/config"
 	"github.com/chihaya/chihaya/stats"
@@ -26,6 +26,8 @@ type ResponseHandler func(http.ResponseWriter, *http.Request, httprouter.Params)
 type Server struct {
 	config   *config.Config
 	tracker  *tracker.Tracker
+	grace    *graceful.Server
+	stopping bool
 }
 
 // makeHandler wraps our ResponseHandlers while timing requests, collecting,
@@ -118,40 +120,53 @@ func (s *Server) connState(conn net.Conn, state http.ConnState) {
 	}
 }
 
-// Serve creates a new Server and proceeds to block while handling requests
+// Serve runs an HTTP server, blocking until the server has shut down.
-// until a graceful shutdown.
+func (s *Server) Serve(addr string) {
-func Serve(cfg *config.Config, tkr *tracker.Tracker) {
+	glog.V(0).Info("Starting HTTP on ", addr)
-	srv := &Server{
-		config:  cfg,
-		tracker: tkr,
-	}
 
-	glog.V(0).Info("Starting on ", cfg.ListenAddr)
+	if s.config.HTTPListenLimit != 0 {
-	if cfg.HTTPListenLimit != 0 {
+		glog.V(0).Info("Limiting connections to ", s.config.HTTPListenLimit)
-		glog.V(0).Info("Limiting connections to ", cfg.HTTPListenLimit)
 	}
 
 	grace := &graceful.Server{
-		Timeout:     cfg.RequestTimeout.Duration,
+		Timeout:     s.config.HTTPRequestTimeout.Duration,
-		ConnState:   srv.connState,
+		ConnState:   s.connState,
-		ListenLimit: cfg.HTTPListenLimit,
+		ListenLimit: s.config.HTTPListenLimit,
+
+		NoSignalHandling: true,
 		Server: &http.Server{
-			Addr:         cfg.ListenAddr,
+			Addr:         addr,
-			Handler:      newRouter(srv),
+			Handler:      newRouter(s),
-			ReadTimeout:  cfg.HTTPReadTimeout.Duration,
+			ReadTimeout:  s.config.HTTPReadTimeout.Duration,
-			WriteTimeout: cfg.HTTPWriteTimeout.Duration,
+			WriteTimeout: s.config.HTTPWriteTimeout.Duration,
 		},
 	}
 
+	s.grace = grace
 	grace.SetKeepAlivesEnabled(false)
+	grace.ShutdownInitiated = func() { s.stopping = true }
 
 	if err := grace.ListenAndServe(); err != nil {
 		if opErr, ok := err.(*net.OpError); !ok || (ok && opErr.Op != "accept") {
 			glog.Errorf("Failed to gracefully run HTTP server: %s", err.Error())
+			return
 		}
 	}
 
-	if err := srv.tracker.Close(); err != nil {
+	glog.Info("HTTP server shut down cleanly")
-		glog.Errorf("Failed to shutdown tracker cleanly: %s", err.Error())
+}
+
+// Stop cleanly shuts down the server.
+func (s *Server) Stop() {
+	if !s.stopping {
+		s.grace.Stop(s.grace.Timeout)
+	}
+}
+
+// NewServer returns a new HTTP server for a given configuration and tracker.
+func NewServer(cfg *config.Config, tkr *tracker.Tracker) *Server {
+	return &Server{
+		config:  cfg,
+		tracker: tkr,
 	}
 }

http/routes.go

@@ -76,7 +76,7 @@ func (s *Server) stats(w http.ResponseWriter, r *http.Request, p httprouter.Para
 func handleTorrentError(err error, w *Writer) (int, error) {
 	if err == nil {
 		return http.StatusOK, nil
-	} else if _, ok := err.(models.ClientError); ok {
+	} else if models.IsPublicError(err) {
 		w.WriteError(err)
 		stats.RecordEvent(stats.ClientError)
 		return http.StatusOK, nil
@@ -86,10 +86,8 @@ func handleTorrentError(err error, w *Writer) (int, error) {
 }
 
 func (s *Server) serveAnnounce(w http.ResponseWriter, r *http.Request, p httprouter.Params) (int, error) {
-	stats.RecordEvent(stats.Announce)
-
 	writer := &Writer{w}
-	ann, err := NewAnnounce(s.config, r, p)
+	ann, err := s.newAnnounce(r, p)
 	if err != nil {
 		return handleTorrentError(err, writer)
 	}
@@ -98,10 +96,8 @@ func (s *Server) serveAnnounce(w http.ResponseWriter, r *http.Request, p httprou
 }
 
 func (s *Server) serveScrape(w http.ResponseWriter, r *http.Request, p httprouter.Params) (int, error) {
-	stats.RecordEvent(stats.Scrape)
-
 	writer := &Writer{w}
-	scrape, err := NewScrape(s.config, r, p)
+	scrape, err := s.newScrape(r, p)
 	if err != nil {
 		return handleTorrentError(err, writer)
 	}

http/tracker.go

@@ -17,8 +17,8 @@ import (
 	"github.com/chihaya/chihaya/tracker/models"
 )
 
-// NewAnnounce parses an HTTP request and generates a models.Announce.
+// newAnnounce parses an HTTP request and generates a models.Announce.
-func NewAnnounce(cfg *config.Config, r *http.Request, p httprouter.Params) (*models.Announce, error) {
+func (s *Server) newAnnounce(r *http.Request, p httprouter.Params) (*models.Announce, error) {
 	q, err := query.New(r.URL.RawQuery)
 	if err != nil {
 		return nil, err
@@ -26,7 +26,7 @@ func NewAnnounce(cfg *config.Config, r *http.Request, p httprouter.Params) (*mod
 
 	compact := q.Params["compact"] != "0"
 	event, _ := q.Params["event"]
-	numWant := requestedPeerCount(q, cfg.NumWantFallback)
+	numWant := requestedPeerCount(q, s.config.NumWantFallback)
 
 	infohash, exists := q.Params["info_hash"]
 	if !exists {
@@ -38,17 +38,34 @@ func NewAnnounce(cfg *config.Config, r *http.Request, p httprouter.Params) (*mod
 		return nil, models.ErrMalformedRequest
 	}
 
-	ipv4, ipv6, err := requestedIP(q, r, &cfg.NetConfig)
-	if err != nil {
-		return nil, models.ErrMalformedRequest
-	}
-
 	port, err := q.Uint64("port")
 	if err != nil {
 		return nil, models.ErrMalformedRequest
 	}
 
 	left, err := q.Uint64("left")
+
+	ipv4, ipv6, err := requestedEndpoint(q, r, &s.config.NetConfig)
+	if err != nil {
+		return nil, models.ErrMalformedRequest
+	}
+
+	var ipv4Endpoint, ipv6Endpoint models.Endpoint
+	if ipv4 != nil {
+		ipv4Endpoint = *ipv4
+		// If the port we couldn't get the port before, fallback to the port param.
+		if ipv4Endpoint.Port == uint16(0) {
+			ipv4Endpoint.Port = uint16(port)
+		}
+	}
+	if ipv6 != nil {
+		ipv6Endpoint = *ipv6
+		// If the port we couldn't get the port before, fallback to the port param.
+		if ipv6Endpoint.Port == uint16(0) {
+			ipv6Endpoint.Port = uint16(port)
+		}
+	}
+
 	if err != nil {
 		return nil, models.ErrMalformedRequest
 	}
@@ -64,24 +81,23 @@ func NewAnnounce(cfg *config.Config, r *http.Request, p httprouter.Params) (*mod
 	}
 
 	return &models.Announce{
-		Config:     cfg,
+		Config:     s.config,
 		Compact:    compact,
 		Downloaded: downloaded,
 		Event:      event,
-		IPv4:       ipv4,
+		IPv4:       ipv4Endpoint,
-		IPv6:       ipv6,
+		IPv6:       ipv6Endpoint,
 		Infohash:   infohash,
 		Left:       left,
 		NumWant:    numWant,
 		Passkey:    p.ByName("passkey"),
 		PeerID:     peerID,
-		Port:       port,
 		Uploaded:   uploaded,
 	}, nil
 }
 
-// NewScrape parses an HTTP request and generates a models.Scrape.
+// newScrape parses an HTTP request and generates a models.Scrape.
-func NewScrape(cfg *config.Config, r *http.Request, p httprouter.Params) (*models.Scrape, error) {
+func (s *Server) newScrape(r *http.Request, p httprouter.Params) (*models.Scrape, error) {
 	q, err := query.New(r.URL.RawQuery)
 	if err != nil {
 		return nil, err
@@ -96,7 +112,7 @@ func NewScrape(cfg *config.Config, r *http.Request, p httprouter.Params) (*model
 	}
 
 	return &models.Scrape{
-		Config: cfg,
+		Config: s.config,
 
 		Passkey:    p.ByName("passkey"),
 		Infohashes: q.Infohashes,
@@ -116,26 +132,26 @@ func requestedPeerCount(q *query.Query, fallback int) int {
 	return fallback
 }
 
-// requestedIP returns the IP addresses for a request. If there are multiple
+// requestedEndpoint returns the IP address and port pairs for a request. If
-// IP addresses in the request, one IPv4 and one IPv6 will be returned.
+// there are multiple in the request, one IPv4 and one IPv6 will be returned.
-func requestedIP(q *query.Query, r *http.Request, cfg *config.NetConfig) (v4, v6 net.IP, err error) {
+func requestedEndpoint(q *query.Query, r *http.Request, cfg *config.NetConfig) (v4, v6 *models.Endpoint, err error) {
 	var done bool
 
 	if cfg.AllowIPSpoofing {
 		if str, ok := q.Params["ip"]; ok {
-			if v4, v6, done = getIPs(str, v4, v6, cfg); done {
+			if v4, v6, done = getEndpoints(str, v4, v6, cfg); done {
 				return
 			}
 		}
 
 		if str, ok := q.Params["ipv4"]; ok {
-			if v4, v6, done = getIPs(str, v4, v6, cfg); done {
+			if v4, v6, done = getEndpoints(str, v4, v6, cfg); done {
 				return
 			}
 		}
 
 		if str, ok := q.Params["ipv6"]; ok {
-			if v4, v6, done = getIPs(str, v4, v6, cfg); done {
+			if v4, v6, done = getEndpoints(str, v4, v6, cfg); done {
 				return
 			}
 		}
@@ -143,47 +159,49 @@ func requestedIP(q *query.Query, r *http.Request, cfg *config.NetConfig) (v4, v6
 
 	if cfg.RealIPHeader != "" {
 		if xRealIPs, ok := r.Header[cfg.RealIPHeader]; ok {
-			if v4, v6, done = getIPs(string(xRealIPs[0]), v4, v6, cfg); done {
+			if v4, v6, done = getEndpoints(string(xRealIPs[0]), v4, v6, cfg); done {
 				return
 			}
 		}
 	} else {
-		if r.RemoteAddr == "" {
+		if r.RemoteAddr == "" && v4 == nil {
-			if v4 == nil {
+			if v4, v6, done = getEndpoints("127.0.0.1", v4, v6, cfg); done {
-				v4 = net.ParseIP("127.0.0.1")
-			}
 				return
 			}
-
-		var host string
-		host, _, err = net.SplitHostPort(r.RemoteAddr)
-
-		if err == nil && host != "" {
-			if v4, v6, done = getIPs(host, v4, v6, cfg); done {
-				return
 		}
+
+		if v4, v6, done = getEndpoints(r.RemoteAddr, v4, v6, cfg); done {
+			return
 		}
 	}
 
 	if v4 == nil && v6 == nil {
 		err = errors.New("failed to parse IP address")
 	}
+
 	return
 }
 
-func getIPs(ipstr string, ipv4, ipv6 net.IP, cfg *config.NetConfig) (net.IP, net.IP, bool) {
+func getEndpoints(ipstr string, ipv4, ipv6 *models.Endpoint, cfg *config.NetConfig) (*models.Endpoint, *models.Endpoint, bool) {
+	host, port, err := net.SplitHostPort(ipstr)
+	if err != nil {
+		host = ipstr
+	}
+
+	// We can ignore this error, because ports that are 0 are assumed to be the
+	// port parameter provided in the "port" param of the announce request.
+	parsedPort, _ := strconv.ParseUint(port, 10, 16)
+
+	if ip := net.ParseIP(host); ip != nil {
+		ipTo4 := ip.To4()
+		if ipv4 == nil && ipTo4 != nil {
+			ipv4 = &models.Endpoint{ipTo4, uint16(parsedPort)}
+		} else if ipv6 == nil && ipTo4 == nil {
+			ipv6 = &models.Endpoint{ip, uint16(parsedPort)}
+		}
+	}
+
 	var done bool
-
-	if ip := net.ParseIP(ipstr); ip != nil {
-		newIPv4 := ip.To4()
-
-		if ipv4 == nil && newIPv4 != nil {
-			ipv4 = newIPv4
-		} else if ipv6 == nil && newIPv4 == nil {
-			ipv6 = ip
-		}
-	}
-
 	if cfg.DualStackedPeers {
 		done = ipv4 != nil && ipv6 != nil
 	} else {

stats/stats.go

@@ -271,15 +271,21 @@ func (s *Stats) handlePeerEvent(ps *PeerStats, event int) {
 
 // RecordEvent broadcasts an event to the default stats queue.
 func RecordEvent(event int) {
+	if DefaultStats != nil {
 		DefaultStats.RecordEvent(event)
 	}
+}
 
 // RecordPeerEvent broadcasts a peer event to the default stats queue.
 func RecordPeerEvent(event int, ipv6 bool) {
+	if DefaultStats != nil {
 		DefaultStats.RecordPeerEvent(event, ipv6)
 	}
+}
 
 // RecordTiming broadcasts a timing event to the default stats queue.
 func RecordTiming(event int, duration time.Duration) {
+	if DefaultStats != nil {
 		DefaultStats.RecordTiming(event, duration)
 	}
+}

tracker/announce.go

@@ -70,6 +70,7 @@ func (tkr *Tracker) HandleAnnounce(ann *models.Announce, w Writer) (err error) {
 		stats.RecordEvent(stats.DeletedTorrent)
 	}
 
+	stats.RecordEvent(stats.Announce)
 	return w.WriteAnnounce(newAnnounceResponse(ann))
 }
 
@@ -263,6 +264,7 @@ func newAnnounceResponse(ann *models.Announce) *models.AnnounceResponse {
 	leechCount := ann.Torrent.Leechers.Len()
 
 	res := &models.AnnounceResponse{
+		Announce:    ann,
 		Complete:    seedCount,
 		Incomplete:  leechCount,
 		Interval:    ann.Config.Announce.Duration,
@@ -272,6 +274,10 @@ func newAnnounceResponse(ann *models.Announce) *models.AnnounceResponse {
 
 	if ann.NumWant > 0 && ann.Event != "stopped" && ann.Event != "paused" {
 		res.IPv4Peers, res.IPv6Peers = getPeers(ann)
+
+		if len(res.IPv4Peers)+len(res.IPv6Peers) == 0 {
+			models.AppendPeer(&res.IPv4Peers, &res.IPv6Peers, ann, ann.Peer)
+		}
 	}
 
 	return res

tracker/models/models.go

@@ -8,7 +8,6 @@ package models
 
 import (
 	"net"
-	"strconv"
 	"strings"
 	"time"
 
@@ -40,9 +39,19 @@ var (
 
 type ClientError string
 type NotFoundError ClientError
+type ProtocolError ClientError
 
 func (e ClientError) Error() string   { return string(e) }
 func (e NotFoundError) Error() string { return string(e) }
+func (e ProtocolError) Error() string { return string(e) }
+
+// IsPublicError determines whether an error should be propogated to the client.
+func IsPublicError(err error) bool {
+	_, cl := err.(ClientError)
+	_, nf := err.(NotFoundError)
+	_, pc := err.(ProtocolError)
+	return cl || nf || pc
+}
 
 // PeerList represents a list of peers: either seeders or leechers.
 type PeerList []Peer
@@ -51,8 +60,8 @@ type PeerList []Peer
 type PeerKey string
 
 // NewPeerKey creates a properly formatted PeerKey.
-func NewPeerKey(peerID string, ip net.IP, port string) PeerKey {
+func NewPeerKey(peerID string, ip net.IP) PeerKey {
-	return PeerKey(peerID + "//" + ip.String() + ":" + port)
+	return PeerKey(peerID + "//" + ip.String())
 }
 
 // IP parses and returns the IP address for a given PeerKey.
@@ -69,9 +78,11 @@ func (pk PeerKey) PeerID() string {
 	return strings.Split(string(pk), "//")[0]
 }
 
-// Port returns the port section of the PeerKey.
+// Endpoint is an IP and port pair.
-func (pk PeerKey) Port() string {
+type Endpoint struct {
-	return strings.Split(string(pk), "//")[2]
+	// Always has length net.IPv4len if IPv4, and net.IPv6len if IPv6
+	IP   net.IP `json:"ip"`
+	Port uint16 `json:"port"`
 }
 
 // Peer is a participant in a swarm.
@@ -79,16 +90,11 @@ type Peer struct {
 	ID           string `json:"id"`
 	UserID       uint64 `json:"user_id"`
 	TorrentID    uint64 `json:"torrent_id"`
-
-	// Always has length net.IPv4len if IPv4, and net.IPv6len if IPv6
-	IP net.IP `json:"ip,omitempty"`
-
-	Port uint64 `json:"port"`
-
 	Uploaded     uint64 `json:"uploaded"`
 	Downloaded   uint64 `json:"downloaded"`
 	Left         uint64 `json:"left"`
 	LastAnnounce int64  `json:"last_announce"`
+	Endpoint
 }
 
 // HasIPv4 determines if a peer's IP address can be represented as an IPv4
@@ -105,7 +111,7 @@ func (p *Peer) HasIPv6() bool {
 
 // Key returns a PeerKey for the given peer.
 func (p *Peer) Key() PeerKey {
-	return NewPeerKey(p.ID, p.IP, strconv.FormatUint(p.Port, 10))
+	return NewPeerKey(p.ID, p.IP)
 }
 
 // Torrent is a swarm for a given torrent file.
@@ -143,14 +149,13 @@ type Announce struct {
 	Compact    bool     `json:"compact"`
 	Downloaded uint64   `json:"downloaded"`
 	Event      string   `json:"event"`
-	IPv4       net.IP `json:"ipv4"`
+	IPv4       Endpoint `json:"ipv4"`
-	IPv6       net.IP `json:"ipv6"`
+	IPv6       Endpoint `json:"ipv6"`
 	Infohash   string   `json:"infohash"`
 	Left       uint64   `json:"left"`
 	NumWant    int      `json:"numwant"`
 	Passkey    string   `json:"passkey"`
 	PeerID     string   `json:"peer_id"`
-	Port       uint64 `json:"port"`
 	Uploaded   uint64   `json:"uploaded"`
 
 	Torrent *Torrent `json:"-"`
@@ -177,12 +182,14 @@ func (a *Announce) ClientID() (clientID string) {
 	return
 }
 
+// HasIPv4 determines whether or not an announce has an IPv4 endpoint.
 func (a *Announce) HasIPv4() bool {
-	return a.IPv4 != nil
+	return a.IPv4.IP != nil
 }
 
+// HasIPv6 determines whether or not an announce has an IPv6 endpoint.
 func (a *Announce) HasIPv6() bool {
-	return a.IPv6 != nil
+	return a.IPv6.IP != nil
 }
 
 // BuildPeer creates the Peer representation of an Announce. When provided nil
@@ -192,7 +199,6 @@ func (a *Announce) HasIPv6() bool {
 func (a *Announce) BuildPeer(u *User, t *Torrent) {
 	a.Peer = &Peer{
 		ID:           a.PeerID,
-		Port:         a.Port,
 		Uploaded:     a.Uploaded,
 		Downloaded:   a.Downloaded,
 		Left:         a.Left,
@@ -211,15 +217,15 @@ func (a *Announce) BuildPeer(u *User, t *Torrent) {
 
 	if a.HasIPv4() && a.HasIPv6() {
 		a.PeerV4 = a.Peer
-		a.PeerV4.IP = a.IPv4
+		a.PeerV4.Endpoint = a.IPv4
 		a.PeerV6 = &*a.Peer
-		a.PeerV6.IP = a.IPv6
+		a.PeerV6.Endpoint = a.IPv6
 	} else if a.HasIPv4() {
 		a.PeerV4 = a.Peer
-		a.PeerV4.IP = a.IPv4
+		a.PeerV4.Endpoint = a.IPv4
 	} else if a.HasIPv6() {
 		a.PeerV6 = a.Peer
-		a.PeerV6.IP = a.IPv6
+		a.PeerV6.Endpoint = a.IPv6
 	} else {
 		panic("models: announce must have an IP")
 	}
@@ -250,6 +256,7 @@ type AnnounceDelta struct {
 
 // AnnounceResponse contains the information needed to fulfill an announce.
 type AnnounceResponse struct {
+	Announce              *Announce
 	Complete, Incomplete  int
 	Interval, MinInterval time.Duration
 	IPv4Peers, IPv6Peers  PeerList

tracker/models/peermap.go

@@ -159,7 +159,7 @@ func (pm *PeerMap) AppendPeers(ipv4s, ipv6s PeerList, ann *Announce, wanted int)
 		} else if peersEquivalent(&peer, ann.Peer) {
 			continue
 		} else {
-			appendPeer(&ipv4s, &ipv6s, ann, &peer, &count)
+			count += AppendPeer(&ipv4s, &ipv6s, ann, &peer)
 		}
 	}
 
@@ -174,7 +174,7 @@ func (pm *PeerMap) AppendPeers(ipv4s, ipv6s PeerList, ann *Announce, wanted int)
 				} else if peersEquivalent(&peer, ann.Peer) {
 					continue
 				} else {
-					appendPeer(&ipv4s, &ipv6s, ann, &peer, &count)
+					count += AppendPeer(&ipv4s, &ipv6s, ann, &peer)
 				}
 			}
 		}
@@ -183,18 +183,20 @@ func (pm *PeerMap) AppendPeers(ipv4s, ipv6s PeerList, ann *Announce, wanted int)
 	return ipv4s, ipv6s
 }
 
-// appendPeer adds a peer to its corresponding peerlist.
+// AppendPeer adds a peer to its corresponding peerlist.
-func appendPeer(ipv4s, ipv6s *PeerList, ann *Announce, peer *Peer, count *int) {
+func AppendPeer(ipv4s, ipv6s *PeerList, ann *Announce, peer *Peer) int {
 	if ann.HasIPv6() && peer.HasIPv6() {
 		*ipv6s = append(*ipv6s, *peer)
-		*count++
+		return 1
 	} else if ann.Config.RespectAF && ann.HasIPv4() && peer.HasIPv4() {
 		*ipv4s = append(*ipv4s, *peer)
-		*count++
+		return 1
 	} else if !ann.Config.RespectAF && peer.HasIPv4() {
 		*ipv4s = append(*ipv4s, *peer)
-		*count++
+		return 1
 	}
+
+	return 0
 }
 
 // peersEquivalent checks if two peers represent the same entity.

tracker/scrape.go

@@ -4,7 +4,10 @@
 
 package tracker
 
-import "github.com/chihaya/chihaya/tracker/models"
+import (
+	"github.com/chihaya/chihaya/stats"
+	"github.com/chihaya/chihaya/tracker/models"
+)
 
 // HandleScrape encapsulates all the logic of handling a BitTorrent client's
 // scrape without being coupled to any transport protocol.
@@ -24,6 +27,7 @@ func (tkr *Tracker) HandleScrape(scrape *models.Scrape, w Writer) (err error) {
 		torrents = append(torrents, torrent)
 	}
 
+	stats.RecordEvent(stats.Scrape)
 	return w.WriteScrape(&models.ScrapeResponse{
 		Files: torrents,
 	})

tracker/tracker.go

@@ -24,6 +24,15 @@ type Tracker struct {
 	*Storage
 }
 
+// Server represents a server for a given BitTorrent tracker protocol.
+type Server interface {
+	// Serve runs the server and blocks until the server has shut down.
+	Serve(addr string)
+
+	// Stop cleanly shuts down the server in a non-blocking manner.
+	Stop()
+}
+
 // New creates a new Tracker, and opens any necessary connections.
 // Maintenance routines are automatically spawned in the background.
 func New(cfg *config.Config) (*Tracker, error) {
@@ -64,7 +73,8 @@ func (tkr *Tracker) LoadApprovedClients(clients []string) {
 }
 
 // Writer serializes a tracker's responses, and is implemented for each
-// response transport used by the tracker.
+// response transport used by the tracker. Only one of these may be called
+// per request, and only once.
 //
 // Note, data passed into any of these functions will not contain sensitive
 // information, so it may be passed back the client freely.

udp/announce_test.go

@@ -0,0 +1,87 @@
+// Copyright 2015 The Chihaya Authors. All rights reserved.
+// Use of this source code is governed by the BSD 2-Clause license,
+// which can be found in the LICENSE file.
+
+package udp
+
+import (
+	"bytes"
+	"encoding/binary"
+	"net"
+	"testing"
+
+	"github.com/chihaya/chihaya/config"
+)
+
+func requestAnnounce(sock *net.UDPConn, connID []byte, hash string) ([]byte, error) {
+	txID := makeTransactionID()
+	peerID := []byte("-UT2210-b4a2h9a9f5c4")
+
+	var request []byte
+	request = append(request, connID...)
+	request = append(request, announceAction...)
+	request = append(request, txID...)
+	request = append(request, []byte(hash)...)
+	request = append(request, peerID...)
+	request = append(request, make([]byte, 8)...) // Downloaded
+	request = append(request, make([]byte, 8)...) // Left
+	request = append(request, make([]byte, 8)...) // Uploaded
+	request = append(request, make([]byte, 4)...) // Event
+	request = append(request, make([]byte, 4)...) // IP
+	request = append(request, make([]byte, 4)...) // Key
+	request = append(request, make([]byte, 4)...) // NumWant
+	request = append(request, make([]byte, 2)...) // Port
+
+	return doRequest(sock, request, txID)
+}
+
+func TestAnnounce(t *testing.T) {
+	srv, done, err := setupTracker(&config.DefaultConfig)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, sock, err := setupSocket()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	connID, err := requestConnectionID(sock)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	announce, err := requestAnnounce(sock, connID, "aaaaaaaaaaaaaaaaaaaa")
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	// Parse the response.
+	var action, txID, interval, leechers, seeders uint32
+	buf := bytes.NewReader(announce)
+	binary.Read(buf, binary.BigEndian, &action)
+	binary.Read(buf, binary.BigEndian, &txID)
+	binary.Read(buf, binary.BigEndian, &interval)
+	binary.Read(buf, binary.BigEndian, &leechers)
+	binary.Read(buf, binary.BigEndian, &seeders)
+
+	if action != uint32(announceActionID) {
+		t.Fatal("expected announce action")
+	}
+
+	if interval != uint32(config.DefaultConfig.Announce.Seconds()) {
+		t.Fatal("incorrect interval")
+	}
+
+	if leechers != uint32(0) {
+		t.Fatal("incorrect leecher count")
+	}
+
+	// We're the only seeder.
+	if seeders != uint32(1) {
+		t.Fatal("incorrect seeder count")
+	}
+
+	srv.Stop()
+	<-done
+}

udp/connection.go

@@ -0,0 +1,90 @@
+// Copyright 2015 The Chihaya Authors. All rights reserved.
+// Use of this source code is governed by the BSD 2-Clause license,
+// which can be found in the LICENSE file.
+
+package udp
+
+import (
+	"bytes"
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/rand"
+	"net"
+)
+
+// ConnectionIDGenerator represents the logic to generate 64-bit UDP
+// connection IDs from peer IP addresses.
+type ConnectionIDGenerator struct {
+	iv, iv2 []byte
+	block   cipher.Block
+}
+
+// NewConnectionIDGenerator creates a ConnectionIDGenerator and generates its
+// AES key and first initialization vector.
+func NewConnectionIDGenerator() (gen *ConnectionIDGenerator, err error) {
+	gen = &ConnectionIDGenerator{}
+	key := make([]byte, 16)
+
+	_, err = rand.Read(key)
+	if err != nil {
+		return
+	}
+
+	gen.block, err = aes.NewCipher(key)
+	if err != nil {
+		return
+	}
+
+	err = gen.NewIV()
+	return
+}
+
+// Generate returns the 64-bit connection ID for an IP
+func (g *ConnectionIDGenerator) Generate(ip net.IP) []byte {
+	return g.generate(ip, g.iv)
+}
+
+func (g *ConnectionIDGenerator) generate(ip net.IP, iv []byte) []byte {
+	for len(ip) < 8 {
+		ip = append(ip, ip...) // Not enough bits in output.
+	}
+
+	ct := make([]byte, 16)
+	stream := cipher.NewCFBDecrypter(g.block, iv)
+	stream.XORKeyStream(ct, ip)
+
+	for i := len(ip) - 1; i >= 8; i-- {
+		ct[i-8] ^= ct[i]
+	}
+
+	return ct[:8]
+}
+
+// Matches checks if the given connection ID matches an IP with the current or
+// previous initialization vectors.
+func (g *ConnectionIDGenerator) Matches(id []byte, ip net.IP) bool {
+	if expected := g.generate(ip, g.iv); bytes.Equal(id, expected) {
+		return true
+	}
+
+	if iv2 := g.iv2; iv2 != nil {
+		if expected := g.generate(ip, iv2); bytes.Equal(id, expected) {
+			return true
+		}
+	}
+
+	return false
+}
+
+// NewIV generates a new initialization vector and rotates the current one.
+func (g *ConnectionIDGenerator) NewIV() error {
+	newiv := make([]byte, 16)
+	if _, err := rand.Read(newiv); err != nil {
+		return err
+	}
+
+	g.iv2 = g.iv
+	g.iv = newiv
+
+	return nil
+}

udp/connection_test.go

@@ -0,0 +1,70 @@
+// Copyright 2015 The Chihaya Authors. All rights reserved.
+// Use of this source code is governed by the BSD 2-Clause license,
+// which can be found in the LICENSE file.
+
+package udp
+
+import (
+	"bytes"
+	"net"
+	"testing"
+)
+
+func TestInitReturnsNoError(t *testing.T) {
+	if _, err := NewConnectionIDGenerator(); err != nil {
+		t.Error("Init returned", err)
+	}
+}
+
+func testGenerateConnectionID(t *testing.T, ip net.IP) {
+	gen, _ := NewConnectionIDGenerator()
+
+	id1 := gen.Generate(ip)
+	id2 := gen.Generate(ip)
+
+	if !bytes.Equal(id1, id2) {
+		t.Errorf("Connection ID mismatch: %x != %x", id1, id2)
+	}
+
+	if len(id1) != 8 {
+		t.Errorf("Connection ID had length: %d != 8", len(id1))
+	}
+
+	if bytes.Count(id1, []byte{0}) == 8 {
+		t.Errorf("Connection ID was 0")
+	}
+}
+
+func TestGenerateConnectionIDIPv4(t *testing.T) {
+	testGenerateConnectionID(t, net.ParseIP("192.168.1.123").To4())
+}
+
+func TestGenerateConnectionIDIPv6(t *testing.T) {
+	testGenerateConnectionID(t, net.ParseIP("1:2:3:4::5:6"))
+}
+
+func TestMatchesWorksWithPreviousIV(t *testing.T) {
+	gen, _ := NewConnectionIDGenerator()
+	ip := net.ParseIP("192.168.1.123").To4()
+
+	id1 := gen.Generate(ip)
+	if !gen.Matches(id1, ip) {
+		t.Errorf("Connection ID mismatch for current IV")
+	}
+
+	gen.NewIV()
+	if !gen.Matches(id1, ip) {
+		t.Errorf("Connection ID mismatch for previous IV")
+	}
+
+	id2 := gen.Generate(ip)
+	gen.NewIV()
+
+	if gen.Matches(id1, ip) {
+		t.Errorf("Connection ID matched for discarded IV")
+	}
+
+	if !gen.Matches(id2, ip) {
+		t.Errorf("Connection ID mismatch for previous IV")
+	}
+}

udp/protocol.go

@@ -0,0 +1,252 @@
+// Copyright 2015 The Chihaya Authors. All rights reserved.
+// Use of this source code is governed by the BSD 2-Clause license,
+// which can be found in the LICENSE file.
+
+package udp
+
+import (
+	"bytes"
+	"encoding/binary"
+	"net"
+
+	"github.com/chihaya/chihaya/stats"
+	"github.com/chihaya/chihaya/tracker/models"
+)
+
+const (
+	connectActionID uint32 = iota
+	announceActionID
+	scrapeActionID
+	errorActionID
+	announceDualStackActionID
+)
+
+var (
+	// initialConnectionID is the magic initial connection ID specified by BEP 15.
+	initialConnectionID = []byte{0, 0, 0x04, 0x17, 0x27, 0x10, 0x19, 0x80}
+
+	// emptyIPs are the value of an IP field that has been left blank.
+	emptyIPv4 = []byte{0, 0, 0, 0}
+	emptyIPv6 = []byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
+
+	// Option-Types described in BEP41 and BEP45.
+	optionEndOfOptions = byte(0x0)
+	optionNOP          = byte(0x1)
+	optionURLData      = byte(0x2)
+	optionIPv6         = byte(0x3)
+
+	// eventIDs map IDs to event names.
+	eventIDs = []string{
+		"",
+		"completed",
+		"started",
+		"stopped",
+	}
+
+	errMalformedPacket = models.ProtocolError("malformed packet")
+	errMalformedIP     = models.ProtocolError("malformed IP address")
+	errMalformedEvent  = models.ProtocolError("malformed event ID")
+	errBadConnectionID = models.ProtocolError("bad connection ID")
+)
+
+// handleTorrentError writes err to w if err is a models.ClientError.
+func handleTorrentError(err error, w *Writer) {
+	if err == nil {
+		return
+	}
+
+	if models.IsPublicError(err) {
+		w.WriteError(err)
+		stats.RecordEvent(stats.ClientError)
+	}
+}
+
+// handlePacket decodes and processes one UDP request, returning the response.
+func (s *Server) handlePacket(packet []byte, addr *net.UDPAddr) (response []byte, actionName string) {
+	if len(packet) < 16 {
+		return // Malformed, no client packets are less than 16 bytes.
+	}
+
+	connID := packet[0:8]
+	action := binary.BigEndian.Uint32(packet[8:12])
+	transactionID := packet[12:16]
+
+	writer := &Writer{
+		buf: new(bytes.Buffer),
+
+		connectionID:  connID,
+		transactionID: transactionID,
+	}
+	defer func() { response = writer.buf.Bytes() }()
+
+	if action != 0 && !s.connIDGen.Matches(connID, addr.IP) {
+		writer.WriteError(errBadConnectionID)
+		return
+	}
+
+	switch action {
+	case connectActionID:
+		actionName = "connect"
+		if !bytes.Equal(connID, initialConnectionID) {
+			return // Malformed packet.
+		}
+
+		writer.writeHeader(0)
+		writer.buf.Write(s.connIDGen.Generate(addr.IP))
+
+	case announceActionID:
+		actionName = "announce"
+		ann, err := s.newAnnounce(packet, addr.IP)
+
+		if err == nil {
+			err = s.tracker.HandleAnnounce(ann, writer)
+		}
+
+		handleTorrentError(err, writer)
+
+	case scrapeActionID:
+		actionName = "scrape"
+		scrape, err := s.newScrape(packet)
+
+		if err == nil {
+			err = s.tracker.HandleScrape(scrape, writer)
+		}
+
+		handleTorrentError(err, writer)
+	}
+
+	return
+}
+
+// newAnnounce decodes one announce packet, returning a models.Announce.
+func (s *Server) newAnnounce(packet []byte, ip net.IP) (*models.Announce, error) {
+	if len(packet) < 98 {
+		return nil, errMalformedPacket
+	}
+
+	infohash := packet[16:36]
+	peerID := packet[36:56]
+
+	downloaded := binary.BigEndian.Uint64(packet[56:64])
+	left := binary.BigEndian.Uint64(packet[64:72])
+	uploaded := binary.BigEndian.Uint64(packet[72:80])
+
+	eventID := packet[83]
+	if eventID > 3 {
+		return nil, errMalformedEvent
+	}
+
+	ipv4bytes := packet[84:88]
+	if s.config.AllowIPSpoofing && !bytes.Equal(ipv4bytes, emptyIPv4) {
+		ip = net.ParseIP(string(ipv4bytes))
+	}
+
+	if ip == nil {
+		return nil, errMalformedIP
+	} else if ipv4 := ip.To4(); ipv4 != nil {
+		ip = ipv4
+	}
+
+	numWant := binary.BigEndian.Uint32(packet[92:96])
+	port := binary.BigEndian.Uint16(packet[96:98])
+
+	announce := &models.Announce{
+		Config:     s.config,
+		Downloaded: downloaded,
+		Event:      eventIDs[eventID],
+		IPv4: models.Endpoint{
+			IP:   ip,
+			Port: port,
+		},
+		Infohash: string(infohash),
+		Left:     left,
+		NumWant:  int(numWant),
+		PeerID:   string(peerID),
+		Uploaded: uploaded,
+	}
+
+	if err := s.handleOptionalParameters(packet, announce); err != nil {
+		return nil, err
+	}
+
+	return announce, nil
+}
+
+// handleOptionalParameters parses the optional parameters as described in BEP41
+// and updates an announce with the values parsed.
+func (s *Server) handleOptionalParameters(packet []byte, announce *models.Announce) error {
+	if len(packet) > 98 {
+		optionStartIndex := 98
+		for optionStartIndex < len(packet)-1 {
+			option := packet[optionStartIndex]
+			switch option {
+			case optionEndOfOptions:
+				return nil
+
+			case optionNOP:
+				optionStartIndex++
+
+			case optionURLData:
+				if optionStartIndex+1 > len(packet)-1 {
+					return errMalformedPacket
+				}
+
+				length := int(packet[optionStartIndex+1])
+				if optionStartIndex+1+length > len(packet)-1 {
+					return errMalformedPacket
+				}
+
+				// TODO: Actually parse the URL Data as described in BEP41.
+
+				optionStartIndex += 1 + length
+
+			case optionIPv6:
+				if optionStartIndex+19 > len(packet)-1 {
+					return errMalformedPacket
+				}
+
+				ipv6bytes := packet[optionStartIndex+1 : optionStartIndex+17]
+				if s.config.AllowIPSpoofing && !bytes.Equal(ipv6bytes, emptyIPv6) {
+					announce.IPv6.IP = net.ParseIP(string(ipv6bytes)).To16()
+					announce.IPv6.Port = binary.BigEndian.Uint16(packet[optionStartIndex+17 : optionStartIndex+19])
+					if announce.IPv6.IP == nil {
+						return errMalformedIP
+					}
+				}
+
+				optionStartIndex += 19
+
+			default:
+				return nil
+			}
+		}
+	}
+
+	// There was no optional parameters to parse.
+	return nil
+}
+
+// newScrape decodes one announce packet, returning a models.Scrape.
+func (s *Server) newScrape(packet []byte) (*models.Scrape, error) {
+	if len(packet) < 36 {
+		return nil, errMalformedPacket
+	}
+
+	var infohashes []string
+	packet = packet[16:]
+
+	if len(packet)%20 != 0 {
+		return nil, errMalformedPacket
+	}
+
+	for len(packet) >= 20 {
+		infohash := packet[:20]
+		infohashes = append(infohashes, string(infohash))
+		packet = packet[20:]
+	}
+
+	return &models.Scrape{
+		Config:     s.config,
+		Infohashes: infohashes,
+	}, nil
+}

udp/scrape_test.go

@@ -0,0 +1,77 @@
+// Copyright 2015 The Chihaya Authors. All rights reserved.
+// Use of this source code is governed by the BSD 2-Clause license,
+// which can be found in the LICENSE file.
+
+package udp
+
+import (
+	"bytes"
+	"fmt"
+	"net"
+	"testing"
+
+	"github.com/chihaya/chihaya/config"
+)
+
+func doRequest(sock *net.UDPConn, request, txID []byte) ([]byte, error) {
+	response := make([]byte, 1024)
+
+	n, err := sendRequest(sock, request, response)
+	if err != nil {
+		return nil, err
+	}
+
+	if !bytes.Equal(response[4:8], txID) {
+		return nil, fmt.Errorf("transaction ID mismatch")
+	}
+
+	return response[:n], nil
+}
+
+func requestScrape(sock *net.UDPConn, connID []byte, hashes []string) ([]byte, error) {
+	txID := makeTransactionID()
+
+	var request []byte
+	request = append(request, connID...)
+	request = append(request, scrapeAction...)
+	request = append(request, txID...)
+
+	for _, hash := range hashes {
+		request = append(request, []byte(hash)...)
+	}
+
+	return doRequest(sock, request, txID)
+}
+
+func TestScrapeEmpty(t *testing.T) {
+	srv, done, err := setupTracker(&config.DefaultConfig)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, sock, err := setupSocket()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	connID, err := requestConnectionID(sock)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	scrape, err := requestScrape(sock, connID, []string{"aaaaaaaaaaaaaaaaaaaa"})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if !bytes.Equal(scrape[:4], errorAction) {
+		t.Error("expected error response")
+	}
+
+	if string(scrape[8:]) != "torrent does not exist\000" {
+		t.Error("expected torrent to not exist")
+	}
+
+	srv.Stop()
+	<-done
+}

udp/udp.go

@@ -0,0 +1,128 @@
+// Copyright 2015 The Chihaya Authors. All rights reserved.
+// Use of this source code is governed by the BSD 2-Clause license,
+// which can be found in the LICENSE file.
+
+// Package udp implements a UDP BitTorrent tracker per BEP 15.
+// IPv6 is currently unsupported as there is no widely-implemented standard.
+package udp
+
+import (
+	"errors"
+	"net"
+	"time"
+
+	"github.com/golang/glog"
+	"github.com/pushrax/bufferpool"
+
+	"github.com/chihaya/chihaya/config"
+	"github.com/chihaya/chihaya/tracker"
+)
+
+// Server represents a UDP torrent tracker.
+type Server struct {
+	config  *config.Config
+	tracker *tracker.Tracker
+	done    bool
+	booting chan struct{}
+	sock    *net.UDPConn
+
+	connIDGen *ConnectionIDGenerator
+}
+
+func (s *Server) serve(listenAddr string) error {
+	if s.sock != nil {
+		return errors.New("server already booted")
+	}
+
+	udpAddr, err := net.ResolveUDPAddr("udp", listenAddr)
+	if err != nil {
+		close(s.booting)
+		return err
+	}
+
+	sock, err := net.ListenUDP("udp", udpAddr)
+	defer sock.Close()
+	if err != nil {
+		close(s.booting)
+		return err
+	}
+
+	if s.config.UDPReadBufferSize > 0 {
+		sock.SetReadBuffer(s.config.UDPReadBufferSize)
+	}
+
+	pool := bufferpool.New(1000, 2048)
+	s.sock = sock
+	close(s.booting)
+
+	for !s.done {
+		buffer := pool.TakeSlice()
+		sock.SetReadDeadline(time.Now().Add(time.Second))
+		n, addr, err := sock.ReadFromUDP(buffer)
+
+		if err != nil {
+			if netErr, ok := err.(net.Error); ok && netErr.Temporary() {
+				pool.GiveSlice(buffer)
+				continue
+			}
+			return err
+		}
+
+		start := time.Now()
+
+		go func() {
+			response, action := s.handlePacket(buffer[:n], addr)
+			pool.GiveSlice(buffer)
+
+			if len(response) > 0 {
+				sock.WriteToUDP(response, addr)
+			}
+
+			if glog.V(2) {
+				duration := time.Since(start)
+				glog.Infof("[UDP - %9s] %s %s", duration, action, addr)
+			}
+		}()
+	}
+
+	return nil
+}
+
+// Serve runs a UDP server, blocking until the server has shut down.
+func (s *Server) Serve(addr string) {
+	glog.V(0).Info("Starting UDP on ", addr)
+
+	go func() {
+		// Generate a new IV every hour.
+		for range time.Tick(time.Hour) {
+			s.connIDGen.NewIV()
+		}
+	}()
+
+	if err := s.serve(addr); err != nil {
+		glog.Errorf("Failed to run UDP server: %s", err.Error())
+	} else {
+		glog.Info("UDP server shut down cleanly")
+	}
+}
+
+// Stop cleanly shuts down the server.
+func (s *Server) Stop() {
+	s.done = true
+	s.sock.SetReadDeadline(time.Now())
+}
+
+// NewServer returns a new UDP server for a given configuration and tracker.
+func NewServer(cfg *config.Config, tkr *tracker.Tracker) *Server {
+	gen, err := NewConnectionIDGenerator()
+	if err != nil {
+		panic(err)
+	}
+
+	return &Server{
+		config:    cfg,
+		tracker:   tkr,
+		connIDGen: gen,
+		booting:   make(chan struct{}),
+	}
+}

udp/udp_test.go

@@ -0,0 +1,132 @@
+// Copyright 2015 The Chihaya Authors. All rights reserved.
+// Use of this source code is governed by the BSD 2-Clause license,
+// which can be found in the LICENSE file.
+
+package udp
+
+import (
+	"bytes"
+	"crypto/rand"
+	"fmt"
+	"net"
+	"testing"
+	"time"
+
+	"github.com/chihaya/chihaya/config"
+	"github.com/chihaya/chihaya/tracker"
+
+	_ "github.com/chihaya/chihaya/backend/noop"
+)
+
+var (
+	testPort       = "34137"
+	connectAction  = []byte{0, 0, 0, byte(connectActionID)}
+	announceAction = []byte{0, 0, 0, byte(announceActionID)}
+	scrapeAction   = []byte{0, 0, 0, byte(scrapeActionID)}
+	errorAction    = []byte{0, 0, 0, byte(errorActionID)}
+)
+
+func setupTracker(cfg *config.Config) (*Server, chan struct{}, error) {
+	tkr, err := tracker.New(cfg)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	srv := NewServer(cfg, tkr)
+	done := make(chan struct{})
+
+	go func() {
+		if err := srv.serve(":" + testPort); err != nil {
+			panic(err)
+		}
+		close(done)
+	}()
+
+	<-srv.booting
+	return srv, done, nil
+}
+
+func setupSocket() (*net.UDPAddr, *net.UDPConn, error) {
+	srvAddr, err := net.ResolveUDPAddr("udp", "localhost:"+testPort)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	sock, err := net.DialUDP("udp", nil, srvAddr)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	return srvAddr, sock, err
+}
+
+func makeTransactionID() []byte {
+	out := make([]byte, 4)
+	rand.Read(out)
+	return out
+}
+
+func sendRequest(sock *net.UDPConn, request, response []byte) (int, error) {
+	if _, err := sock.Write(request); err != nil {
+		return 0, err
+	}
+
+	sock.SetReadDeadline(time.Now().Add(time.Second))
+	n, err := sock.Read(response)
+
+	if err != nil {
+		if netErr, ok := err.(net.Error); ok && netErr.Timeout() {
+			return 0, fmt.Errorf("no response from tracker: %s", err)
+		}
+	}
+
+	return n, err
+}
+
+func requestConnectionID(sock *net.UDPConn) ([]byte, error) {
+	txID := makeTransactionID()
+	request := []byte{}
+
+	request = append(request, initialConnectionID...)
+	request = append(request, connectAction...)
+	request = append(request, txID...)
+
+	response := make([]byte, 1024)
+	n, err := sendRequest(sock, request, response)
+	if err != nil {
+		return nil, err
+	}
+
+	if n != 16 {
+		return nil, fmt.Errorf("packet length mismatch: %d != 16", n)
+	}
+
+	if !bytes.Equal(response[4:8], txID) {
+		return nil, fmt.Errorf("transaction ID mismatch")
+	}
+
+	if !bytes.Equal(response[0:4], connectAction) {
+		return nil, fmt.Errorf("action mismatch")
+	}
+
+	return response[8:16], nil
+}
+
+func TestRequestConnectionID(t *testing.T) {
+	srv, done, err := setupTracker(&config.DefaultConfig)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	_, sock, err := setupSocket()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err = requestConnectionID(sock); err != nil {
+		t.Fatal(err)
+	}
+
+	srv.Stop()
+	<-done
+}

udp/writer.go

@@ -0,0 +1,97 @@
+// Copyright 2015 The Chihaya Authors. All rights reserved.
+// Use of this source code is governed by the BSD 2-Clause license,
+// which can be found in the LICENSE file.
+
+package udp
+
+import (
+	"bytes"
+	"encoding/binary"
+	"time"
+
+	"github.com/chihaya/chihaya/tracker/models"
+)
+
+// Writer implements the tracker.Writer interface for the UDP protocol.
+type Writer struct {
+	buf *bytes.Buffer
+
+	connectionID  []byte
+	transactionID []byte
+}
+
+// WriteError writes the failure reason as a null-terminated string.
+func (w *Writer) WriteError(err error) error {
+	w.writeHeader(errorActionID)
+	w.buf.WriteString(err.Error())
+	w.buf.WriteRune('\000')
+	return nil
+}
+
+// WriteAnnounce encodes an announce response by selecting the proper announce
+// format based on the BitTorrent spec.
+func (w *Writer) WriteAnnounce(resp *models.AnnounceResponse) (err error) {
+	if resp.Announce.HasIPv6() {
+		err = w.WriteAnnounceIPv6(resp)
+	} else {
+		err = w.WriteAnnounceIPv4(resp)
+	}
+
+	return
+}
+
+// WriteAnnounceIPv6 encodes an announce response according to BEP45.
+func (w *Writer) WriteAnnounceIPv6(resp *models.AnnounceResponse) error {
+	w.writeHeader(announceDualStackActionID)
+	binary.Write(w.buf, binary.BigEndian, uint32(resp.Interval/time.Second))
+	binary.Write(w.buf, binary.BigEndian, uint32(resp.Incomplete))
+	binary.Write(w.buf, binary.BigEndian, uint32(resp.Complete))
+	binary.Write(w.buf, binary.BigEndian, uint32(len(resp.IPv4Peers)))
+	binary.Write(w.buf, binary.BigEndian, uint32(len(resp.IPv6Peers)))
+
+	for _, peer := range resp.IPv4Peers {
+		w.buf.Write(peer.IP)
+		binary.Write(w.buf, binary.BigEndian, peer.Port)
+	}
+
+	for _, peer := range resp.IPv6Peers {
+		w.buf.Write(peer.IP)
+		binary.Write(w.buf, binary.BigEndian, peer.Port)
+	}
+
+	return nil
+}
+
+// WriteAnnounceIPv4 encodes an announce response according to BEP15.
+func (w *Writer) WriteAnnounceIPv4(resp *models.AnnounceResponse) error {
+	w.writeHeader(announceActionID)
+	binary.Write(w.buf, binary.BigEndian, uint32(resp.Interval/time.Second))
+	binary.Write(w.buf, binary.BigEndian, uint32(resp.Incomplete))
+	binary.Write(w.buf, binary.BigEndian, uint32(resp.Complete))
+
+	for _, peer := range resp.IPv4Peers {
+		w.buf.Write(peer.IP)
+		binary.Write(w.buf, binary.BigEndian, peer.Port)
+	}
+
+	return nil
+}
+
+// WriteScrape encodes a scrape response according to BEP15.
+func (w *Writer) WriteScrape(resp *models.ScrapeResponse) error {
+	w.writeHeader(scrapeActionID)
+
+	for _, torrent := range resp.Files {
+		binary.Write(w.buf, binary.BigEndian, uint32(torrent.Seeders.Len()))
+		binary.Write(w.buf, binary.BigEndian, uint32(torrent.Snatches))
+		binary.Write(w.buf, binary.BigEndian, uint32(torrent.Leechers.Len()))
+	}
+
+	return nil
+}
+
+// writeHeader writes the action and transaction ID to the response.
+func (w *Writer) writeHeader(action uint32) {
+	binary.Write(w.buf, binary.BigEndian, action)
+	w.buf.Write(w.transactionID)
+}