cmd/pkgserver: expose size and store pre-encoded ident

This change also handles SIGSEGV correctly in newStatusHandler, and makes serving status fully zero copy.

Signed-off-by: Ophestra <cat@gensokyo.uk>

cmd/pkgserver/api.go

@@ -1,9 +1,7 @@
 package main
 
 import (
-	"bytes"
 	"encoding/json"
-	"io"
 	"log"
 	"net/http"
 	"path"
@@ -11,7 +9,6 @@ import (
 	"sync"
 
 	"hakurei.app/internal/info"
-	"hakurei.app/internal/pkg"
 	"hakurei.app/internal/rosa"
 )
 
@@ -50,19 +47,27 @@ func (index *packageIndex) newStatusHandler(disposition bool) http.HandlerFunc {
 		if disposition {
 			contentType = "application/octet-stream"
 
+			// quoting like this is unsound, but okay, because metadata is hardcoded
 			contentDisposition := `attachment; filename="`
 			contentDisposition += m.Name + "-"
 			if m.Version != "" {
 				contentDisposition += m.Version + "-"
 			}
-			contentDisposition += pkg.Encode(m.ident.Value()) + `.log"`
+			contentDisposition += m.ids + `.log"`
 			w.Header().Set("Content-Disposition", contentDisposition)
 		}
 		w.Header().Set("Content-Type", contentType)
 		w.Header().Set("Cache-Control", "no-cache, no-store, must-revalidate")
-		_, err := io.Copy(w, bytes.NewReader(m.status))
-		if err != nil {
-			http.Error(w, err.Error(), http.StatusInternalServerError)
+		if err := func() (err error) {
+			defer index.handleAccess(&err)()
+			_, err = w.Write(m.status)
+			return
+		}(); err != nil {
+			log.Println(err)
+			http.Error(
+				w, "cannot deliver status, contact maintainers",
+				http.StatusInternalServerError,
+			)
 		}
 	}
 }