allow redirection for items without a space in the desc again

Broken in a4b8112b19763cbd2c12b81d55bc7d43a591d610.
If an item has a description which includes no space and is redirected
to another mirror the code which wants to rewrite the description
expects a space in there, but can't find it and the unguarded substr
command on the string will fail with an exception thrown…

Guarding it properly and everything is fine.

(cherry picked from commit 84ac6edfabe1c92d67e8d441e04216ad33c89165)

diff --git a/apt-pkg/acquire-worker.cc b/apt-pkg/acquire-worker.cc
index ca1fd4836c3311c668413255892620b1ca462b79..6cf6c856e1dbdf617a60022aeb36fcae1ae12bea 100644 (file)
--- a/apt-pkg/acquire-worker.cc
+++ b/apt-pkg/acquire-worker.cc
@@ -273,16 +273,19 @@ bool pkgAcquire::Worker::RunMessages()
               // if we change site, treat it as a mirror change
               if (URI::SiteOnly(NewURI) != URI::SiteOnly(desc.URI))
               {
-                 std::string const OldSite = desc.Description.substr(0, desc.Description.find(" "));
-                 if (likely(APT::String::Startswith(desc.URI, OldSite)))
+                 auto const firstSpace = desc.Description.find(" ");
+                 if (firstSpace != std::string::npos)
                  {
-                    std::string const OldExtra = desc.URI.substr(OldSite.length() + 1);
-                    if (likely(APT::String::Endswith(NewURI, OldExtra)))
+                    std::string const OldSite = desc.Description.substr(0, firstSpace);
+                    if (likely(APT::String::Startswith(desc.URI, OldSite)))
                     {
-                       std::string const NewSite = NewURI.substr(0, NewURI.length() - OldExtra.length());
-                       Owner->UsedMirror = URI::ArchiveOnly(NewSite);
-                       if (desc.Description.find(" ") != string::npos)
-                          desc.Description.replace(0, desc.Description.find(" "), Owner->UsedMirror);
+                       std::string const OldExtra = desc.URI.substr(OldSite.length() + 1);
+                       if (likely(APT::String::Endswith(NewURI, OldExtra)))
+                       {
+                          std::string const NewSite = NewURI.substr(0, NewURI.length() - OldExtra.length());
+                          Owner->UsedMirror = URI::ArchiveOnly(NewSite);
+                          desc.Description.replace(0, firstSpace, Owner->UsedMirror);
+                       }
                     }
                  }
               }

diff --git a/test/integration/test-handle-redirect-as-used-mirror-change b/test/integration/test-handle-redirect-as-used-mirror-change
index 3a8b1fecd905da1ce9de9616a29ffe3d9514d052..7978d752447530464ac53e058062e2d1f471a9cd 100755 (executable)
--- a/test/integration/test-handle-redirect-as-used-mirror-change
+++ b/test/integration/test-handle-redirect-as-used-mirror-change
@@ -22,3 +22,6 @@ Reading package lists..." aptget update
 
 testsuccessequal "Hit:1 http://0.0.0.0:${APTHTTPPORT} unstable InRelease
 Reading package lists..." aptget update
+
+testsuccess apthelper download-file "http://localhost:${APTHTTPPORT}/redirectme/dists/unstable/InRelease" inrelease
+testsuccess test -s inrelease