Garbage collector: Don't follow symlinks arbitrarily

Only indirect roots (symlinks to symlinks to the Nix store) are now
supported.

1 files changed, 9 insertions, 0 deletions

diff --git a/src/libutil/util.cc b/src/libutil/util.cc
index b1231e455..dad5f624b 100644
--- a/src/libutil/util.cc
+++ b/src/libutil/util.cc
@@ -148,6 +148,15 @@ string baseNameOf(const Path & path)
 }
 
 
+bool isInDir(const Path & path, const Path & dir)
+{
+    return path[0] == '/'
+        && string(path, 0, dir.size()) == dir
+        && path.size() >= dir.size() + 2
+        && path[dir.size()] == '/';
+}
+
+
 struct stat lstat(const Path & path)
 {
     struct stat st;