Use a more gitignore style matching

Use a rightmost match for / so that if we end up with a Section: a/b/c,
a 'c' matcher still matches.

If the section does not contain any /, it can be matched using /pattern,
e.g. /c only matches Section: c, but not Section: a/b/c.

2 files changed, 4 insertions, 4 deletions

diff --git a/apt-pkg/depcache.cc b/apt-pkg/depcache.cc
index b19d180a4..322bf1bbe 100644
--- a/apt-pkg/depcache.cc
+++ b/apt-pkg/depcache.cc
@@ -90,10 +90,10 @@ static bool SectionInSubTree(char const * const SubTree, std::string_view Needle
 {
    if (ConfigValueInSubTree(SubTree, Needle))
       return true;
-   auto const sub = Needle.find('/');
+   auto const sub = Needle.rfind('/');
    if (sub == std::string_view::npos)
    {
-      std::string special{"<undefined>/"};
+      std::string special{"/"};
       special.append(Needle);
       return ConfigValueInSubTree(SubTree, special);
    }
diff --git a/cmdline/apt-mark.cc b/cmdline/apt-mark.cc
index 46d3ca5b8..3f3b008ba 100644
--- a/cmdline/apt-mark.cc
+++ b/cmdline/apt-mark.cc
@@ -163,10 +163,10 @@ static bool SectionInSubTree(char const * const SubTree, std::string_view Needle
 {
    if (ConfigValueInSubTree(SubTree, Needle))
       return true;
-   auto const sub = Needle.find('/');
+   auto const sub = Needle.rfind('/');
    if (sub == std::string_view::npos)
    {
-      std::string special{"<undefined>/"};
+      std::string special{"/"};
       special.append(Needle);
       return ConfigValueInSubTree(SubTree, special);
    }