1 files changed, 65 insertions, 0 deletions
diff --git a/lib/portage/util/_dyn_libs/dyn_libs.py b/lib/portage/util/_dyn_libs/dyn_libs.py
new file mode 100644
index 000000000..6f8a07d70
--- /dev/null
+++ b/lib/portage/util/_dyn_libs/dyn_libs.py
@@ -0,0 +1,65 @@
+# Copyright 2021-2024 Gentoo Authors
+# Distributed under the terms of the GNU General Public License v2
+
+import os
+import stat
+
+import portage
+
+
+def installed_dynlibs(directory):
+    """
+    This traverses installed *.so symlinks to check if they point to
+    regular files. If a symlink target is outside of the top directory,
+    traversal follows the corresponding file inside the top directory
+    if it exists, and otherwise stops following the symlink.
+    """
+    directory_prefix = f"{directory.rstrip(os.sep)}{os.sep}"
+    for parent, _dirnames, filenames in os.walk(directory):
+        for filename in filenames:
+            if filename.endswith(".so"):
+                filename_abs = os.path.join(parent, filename)
+                target = filename_abs
+                levels = 0
+                while True:
+                    try:
+                        st = os.lstat(target)
+                    except OSError:
+                        break
+                    if stat.S_ISREG(st.st_mode):
+                        return True
+                    elif stat.S_ISLNK(st.st_mode):
+                        levels += 1
+                        if levels == 40:
+                            portage.writemsg(
+                                f"too many levels of symbolic links: {filename_abs}\n",
+                                noiselevel=-1,
+                            )
+                            break
+                        target = portage.abssymlink(target)
+                        if not target.startswith(directory_prefix):
+                            # If target is outside the top directory, then follow the
+                            # corresponding file inside the top directory if it exists,
+                            # and otherwise stop following.
+                            target = os.path.join(
+                                directory_prefix, target.lstrip(os.sep)
+                            )
+                    else:
+                        break
+    return False
+
+
+def check_dyn_libs_inconsistent(directory, provides):
+    """Checks directory for whether any dynamic libraries were installed and
+    if PROVIDES corresponds."""
+
+    # Let's check if we've got inconsistent results.
+    # If we're installing dynamic libraries (.so files), we should
+    # really have a PROVIDES.
+    # (This is a complementary check at the point of ingestion for the
+    # creation check in doebuild.py)
+    # Note: we could check a non-empty PROVIDES against the list of .sos,
+    # but this doesn't gain us anything. We're interested in failure
+    # to properly parse the installed files at all, which should really
+    # be a global problem (e.g. bug #811462)
+    return not provides and installed_dynlibs(directory)