Resolve intermediate symlinks in resolveExprPath

This addresses some cases of NixOS#2109
ony · Mar 31, 2021 · 8281792 · 8281792
1 parent 3c82d9d
commit 8281792
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Showing 2 changed files with 6 additions and 16 deletions.
diff --git a/src/libexpr/parser.y b/src/libexpr/parser.y
@@ -605,23 +605,13 @@ Path resolveExprPath(Path path)
 {
     assert(path[0] == '/');
 
-    unsigned int followCount = 0, maxFollow = 1024;
-
-    /* If `path' is a symlink, follow it.  This is so that relative
+    /* Expand all symlinks in `path`. This is so that relative
        path references work. */
-    struct stat st;
-    while (true) {
-        // Basic cycle/depth limit to avoid infinite loops.
-        if (++followCount >= maxFollow)
-            throw Error("too many symbolic links encountered while traversing the path '%s'", path);
-        st = lstat(path);
-        if (!S_ISLNK(st.st_mode)) break;
-        path = absPath(readLink(path), dirOf(path));
-    }
+    path = absPath(path, {}, true);
 
     /* If `path' refers to a directory, append `/default.nix'. */
-    if (S_ISDIR(st.st_mode))
-        path = canonPath(path + "/default.nix");
+    if (getFileType(path) == DT_DIR)
+        path = canonPath(path + "/default.nix", true);
 
     return path;
 }

diff --git a/tests/check-imports.sh b/tests/check-imports.sh
@@ -47,10 +47,10 @@ testImportFile $TEST_ROOT/example/dir/subdir/alt-good.nix
 testImportFile $TEST_ROOT/example/dir/subdir
 
 # two-level relative import from path with symlink dir
-# FIXME: testImportFile $TEST_ROOT/example/dir/subdir/import-good.nix
+testImportFile $TEST_ROOT/example/dir/subdir/import-good.nix
 
 # relative traverse of symlink dir
 # FIXME: testImportFile $TEST_ROOT/example/dir/subdir/../good.nix
 
 # dir import with symlinked default.nix
-# FIXME: testImportFile $TEST_ROOT/example/alt-dir
+testImportFile $TEST_ROOT/example/alt-dir