initial commit

3 files changed, 220 insertions, 0 deletions

diff --git a/src/util/fd.go b/src/util/fd.go
new file mode 100644
index 0000000..17c64cd
--- /dev/null
+++ b/src/util/fd.go
@@ -0,0 +1,101 @@
+// Copyright 2015-2016 Luke Shumaker
+
+package util
+
+import (
+	"net"
+	"os"
+	"strings"
+	"fmt"
+	"sync"
+	"strconv"
+
+	sd "lukeshu.com/git/go/libsystemd/sd_daemon"
+)
+
+var fdsLock sync.Mutex
+var fds = map[int]*os.File{}
+var sdFds = map[string]int{}
+
+func init() {
+	fds[0] = os.Stdin
+	fds[1] = os.Stdout
+	fds[2] = os.Stderr
+	fromSd := sd.ListenFds(true)
+	if fromSd == nil {
+		return
+	}
+	for i, file := range fromSd {
+		fds[i+3] = file
+		sdFds[file.Name()] = i+3
+	}
+}
+
+func FdNameToNum(name string) int {
+	switch name {
+	case "stdin":
+		return 0
+	case "stdout":
+		return 1
+	case "stderr":
+		return 2
+	case "systemd":
+		if len(sdFds) == 0 {
+			return -1
+		}
+		return 3
+	default:
+		if n, err := strconv.Atoi(name); err == nil {
+			if n >= 0 {
+				return n
+			}
+		} else if strings.HasPrefix(name, "systemd:") {
+			name = strings.TrimPrefix(name, "systemd")
+			n, ok := sdFds[name]
+			if ok {
+				return n
+			} else if n, err := strconv.Atoi(name); err == nil && n < len(sdFds) {
+				return n+3
+			}
+		}
+		return -1
+	}
+}
+
+func FdFile(fd int) *os.File {
+	fdsLock.Lock()
+	defer fdsLock.Unlock()
+	file, ok := fds[fd]
+	if ok {
+		return file
+	}
+	file = os.NewFile(uintptr(fd), fmt.Sprintf("/dev/fd/%d", fd))
+	fds[fd] = file
+	return file
+}
+
+func StreamListener(stype, saddr string) (net.Listener, error) {
+	switch stype {
+	case "fd":
+		return net.FileListener(FdFile(FdNameToNum(saddr)))
+	default: /* case "tcp", "tcp4", "tcp6", "unix", "unixpacket": */
+		return net.Listen(stype, saddr)
+	}
+}
+
+func PacketListener(stype, saddr string) (net.PacketConn, error) {
+	switch stype {
+	case "fd":
+		return net.FilePacketConn(FdFile(FdNameToNum(saddr)))
+	default: /* case "udp", "udp4", "udp6", "ip", "ip4", "ip6", "unixgram": */
+		return net.ListenPacket(stype, saddr)
+	}
+}
+
+// For completeless, I might want to implement methods for each of
+// these:
+//  - FIFO
+//  - Special
+//  - Netlink
+//  - MessageQueue
+//  - USBFunction
diff --git a/src/util/http.go b/src/util/http.go
new file mode 100644
index 0000000..6c216cf
--- /dev/null
+++ b/src/util/http.go
@@ -0,0 +1,63 @@
+package util
+
+import (
+	"bytes"
+	"fmt"
+	"log"
+	"net/http"
+	"runtime"
+	"strconv"
+)
+
+type httpResponseBuffer struct {
+	inner  http.ResponseWriter
+	buf    bytes.Buffer
+	status int
+}
+
+func (o *httpResponseBuffer) Header() http.Header {
+	return o.inner.Header()
+}
+
+func (o *httpResponseBuffer) Write(data []byte) (int, error) {
+	return o.buf.Write(data)
+}
+
+func (o *httpResponseBuffer) WriteHeader(status int) {
+	o.status = status
+}
+
+type SaneHTTPHandler struct {
+	Inner http.Handler
+}
+
+func (h SaneHTTPHandler) ServeHTTP(out http.ResponseWriter, in *http.Request) {
+	HTTPHandlerFuncWrapper(out, in, h.Inner.ServeHTTP)
+}
+
+func HTTPHandlerFuncWrapper(out http.ResponseWriter, in *http.Request, fn http.HandlerFunc) {
+	buf := httpResponseBuffer{
+		inner:  out,
+		status: http.StatusOK,
+	}
+	ok := true
+	func() {
+		defer func() {
+			if r := recover(); r != nil {
+				const size = 64 << 10
+				buf := make([]byte, size)
+				buf = buf[:runtime.Stack(buf, false)]
+				st := fmt.Sprintf("%[1]T(%#[1]v) => %[1]v\n\n%[2]s", r, string(buf))
+				log.Printf("panic serving %v\n\n%s", in.URL, st)
+				http.Error(out, fmt.Sprintf("500 Internal Server Error:\n\n%s", st), 500)
+				ok = false
+			}
+		}()
+		fn(&buf, in)
+	}()
+	if ok {
+		out.Header().Set("Content-Length", strconv.Itoa(buf.buf.Len()))
+		out.WriteHeader(buf.status)
+		buf.buf.WriteTo(out)
+	}
+}
diff --git a/src/util/template.go b/src/util/template.go
new file mode 100644
index 0000000..f42875a
--- /dev/null
+++ b/src/util/template.go
@@ -0,0 +1,56 @@
+package util
+
+import (
+	"path"
+	"text/template"
+	"time"
+)
+
+func NewTemplate(filenames ...string) *template.Template {
+	return template.Must(template.New(path.Base(filenames[0])).
+		Funcs(template.FuncMap{
+			// Form input helpers
+			"value": func(v interface{}) string {
+				if v == nil {
+					return ""
+				}
+				return "value=\"" + template.HTMLEscapeString(v.(string)) + "\""
+			},
+			"checked": func(v1 interface{}, v2 interface{}) string {
+				if v1 == nil || v2 == nil {
+					return ""
+				}
+				if v1 == v2 {
+					return "checked"
+				}
+				return ""
+			},
+			"selected": func(v1 interface{}, v2 interface{}) string {
+				if v1 == nil || v2 == nil {
+					return ""
+				}
+				if v1 == v2 {
+					return "selected"
+				}
+				return ""
+			},
+			// Form result helpers
+			"q": func(v interface{}) string {
+				if v == nil || v.(string) == "" {
+					return "<output class=none>none</output>"
+				}
+				return "<output><q>" + template.HTMLEscapeString(v.(string)) + "</q></output>"
+			},
+			"have": func(v interface{}) bool {
+				return v != nil && v.(string) == "on"
+			},
+			"date": func(v string) string {
+				t, err := time.Parse("2006-01-02", v)
+				if err != nil {
+					panic(err)
+				}
+				return t.Format("January 2, 2006")
+			},
+		}).
+		ParseFiles(filenames...))
+}