From 45815554ce2d9ce0a12c21e0a5b37bc71435d74a Mon Sep 17 00:00:00 2001
From: Thomas Waldmann <tw@waldmann-edv.de>
Date: Fri, 19 Jan 2024 18:13:53 +0100
Subject: [PATCH] check_can_create_repository: deal with PermissionErrors, see
 #7016

borg init calls this. If there is a PermissionError, it is
usually fs permission issue at path or its parent directory.

Don't give a traceback, but rather an error msg and a specific exit code.
---
 docs/internals/frontends.rst |  2 ++
 src/borg/remote.py           |  2 ++
 src/borg/repository.py       | 19 +++++++++++++++++--
 3 files changed, 21 insertions(+), 2 deletions(-)

diff --git a/docs/internals/frontends.rst b/docs/internals/frontends.rst
index e90ce61a..786667fd 100644
--- a/docs/internals/frontends.rst
+++ b/docs/internals/frontends.rst
@@ -612,6 +612,8 @@ Errors
         There is already something at {}.
     Repository.StorageQuotaExceeded rc: 20 traceback: no
         The storage quota ({}) has been exceeded ({}). Try deleting some archives.
+    Repository.PathPermissionDenied rc: 21 traceback: no
+        Permission denied to {}.
 
     MandatoryFeatureUnsupported rc: 25 traceback: no
         Unsupported repository feature(s) {}. A newer version of borg is required to access this repository.
diff --git a/src/borg/remote.py b/src/borg/remote.py
index 0aa63622..37d74150 100644
--- a/src/borg/remote.py
+++ b/src/borg/remote.py
@@ -780,6 +780,8 @@ class RemoteRepository:
                 raise IntegrityError(args[0])
             elif error == "PathNotAllowed":
                 raise PathNotAllowed(args[0])
+            elif error == "PathPermissionDenied":
+                raise Repository.PathPermissionDenied(args[0])
             elif error == "ParentPathDoesNotExist":
                 raise Repository.ParentPathDoesNotExist(args[0])
             elif error == "ObjectNotFound":
diff --git a/src/borg/repository.py b/src/borg/repository.py
index 7499946f..079fbc21 100644
--- a/src/borg/repository.py
+++ b/src/borg/repository.py
@@ -188,6 +188,11 @@ class Repository:
 
         exit_mcode = 20
 
+    class PathPermissionDenied(Error):
+        """Permission denied to {}."""
+
+        exit_mcode = 21
+
     def __init__(
         self,
         path,
@@ -299,13 +304,23 @@ class Repository:
             st = os.stat(path)
         except FileNotFoundError:
             pass  # nothing there!
+        except PermissionError:
+            raise self.PathPermissionDenied(path) from None
         else:
             # there is something already there!
             if self.is_repository(path):
                 raise self.AlreadyExists(path)
-            if not stat.S_ISDIR(st.st_mode) or os.listdir(path):
+            if not stat.S_ISDIR(st.st_mode):
                 raise self.PathAlreadyExists(path)
-            # an empty directory is acceptable for us.
+            try:
+                files = os.listdir(path)
+            except PermissionError:
+                raise self.PathPermissionDenied(path) from None
+            else:
+                if files:  # a dir, but not empty
+                    raise self.PathAlreadyExists(path)
+                else:  # an empty directory is acceptable for us.
+                    pass
 
         while True:
             # Check all parent directories for Borg's repository README