add --nofollow flag to copy symbolic links verbatim

backupy/cli.py

@@ -88,6 +88,8 @@ def main() -> int:
                              "Disable archiving files before overwriting/deleting to:\n"
                              "   <source|dest>/.backupy/Archives/yymmdd-HHMM/\n"
                              "   <source|dest>/.backupy/Trash/yymmdd-HHMM/"))
+    group2.add_argument("--nofollow", dest="nofollow", action="store_true",
+                        help=getString("Do not follow symlinks when copying files"))
     group2.add_argument("--nomoves", dest="nomoves", action="store_true",
                         help=getString("Do not detect when files are moved or renamed"))
     group3.add_argument("--noprompt", dest="noprompt", action="store_true",

backupy/config.py

@@ -31,6 +31,7 @@ def __init__(self, config: dict):
         self.filter_exclude_list = None
         self.noarchive = False
         self.nocolour = False
+        self.nofollow = False
         self.nolog = False
         self.nomoves = False
         self.noprompt = False

backupy/fileman.py

@@ -37,6 +37,9 @@ def __init__(self, config: ConfigObject, source: FileScanner, dest: FileScanner,
         self.config = config
         self.source = source
         self.dest = dest
+        # update file operation functions from config
+        if self.config.nofollow:
+            FileManager.copy_function = lambda source, dest: shutil.copy2(source, dest, follow_symlinks=False)
         # use other backend
         if self.config.use_rsync:
             def rsync_proc(source, dest):

backupy/filescanner.py

@@ -56,6 +56,10 @@ def __init__(self, directory_root_path: str, unique_id: str,
         self.ignored_toplevel_folders = list(set([config.archive_dir, config.log_dir, config.trash_dir, config.config_dir]))
         self.force_posix_path_sep = config.force_posix_path_sep
         self.write_database_x2 = config.write_database_x2 and not config.scan_only
+        self.follow_symlinks = not config.nofollow
+        # self.opener = None
+        # if config.nofollow:
+        #     self.opener = lambda path, flags: os.open(path, flags | os.O_PATH | os.O_NOFOLLOW)
         # Init other variables
         self.dir = directory_root_path
         self.other_dir = other_root_path
@@ -148,10 +152,14 @@ def getCrc(self, relative_path: str, recalc: bool = False) -> str:
 
     def calcCrc(self, file_path: str, prev: int = 0) -> str:
         try:
-            with open(file_path, "rb") as f:
-                for line in f:
-                    prev = zlib.crc32(line, prev)
-            return "%X" % (prev & 0xFFFFFFFF)
+            if self.follow_symlinks or not os.path.islink(file_path):
+                with open(file_path, "rb") as f:
+                    for line in f:
+                        prev = zlib.crc32(line, prev)
+                return "%X" % (prev & 0xFFFFFFFF)
+            else:
+                crc = zlib.crc32(os.readlink(file_path).encode())
+                return "%X" % (crc & 0xFFFFFFFF)
         except Exception:
             # file either removed by user, or another program such as antimalware (using realtime monitoring) during scan, or lack permissions
             raise Exception("Exiting, error trying to read file: " + file_path)
@@ -246,8 +254,9 @@ def scanDir(self, stdout_status_bar: bool) -> None:
 
     def scanFile(self, full_path: str, relative_path: str) -> None:
         # get file attributes and create entry
-        size = os.path.getsize(full_path)
-        mtime = os.path.getmtime(full_path)
+        stat = os.stat(full_path, follow_symlinks=self.follow_symlinks)
+        size = stat.st_size
+        mtime = stat.st_mtime
         self.dict_current[relative_path] = {"size": size, "mtime": mtime}
         if self.compare_mode == "crc":
             self.dict_current[relative_path]["crc"] = self.calcCrc(full_path)