Add return code functions (#2199)

(cherry picked from commit 4b33c3fe143a1cc52ec8e566232ae03e33440a2b)

borg/archiver.py

@@ -23,7 +23,7 @@ from .helpers import Error, location_validator, archivename_validator, format_li
     PathPrefixPattern, to_localtime, timestamp, safe_timestamp, bin_to_hex, get_cache_dir, prune_within, prune_split, \
     Manifest, NoManifestError, remove_surrogates, format_archive, check_extension_modules, Statistics, \
     dir_is_tagged, bigint_to_int, ChunkerParams, CompressionSpec, PrefixSpec, is_slow_msgpack, yes, sysinfo, \
-    EXIT_SUCCESS, EXIT_WARNING, EXIT_ERROR, log_multi, PatternMatcher, ErrorIgnoringTextIOWrapper
+    EXIT_SUCCESS, EXIT_WARNING, EXIT_ERROR, log_multi, PatternMatcher, ErrorIgnoringTextIOWrapper, set_ec
 from .helpers import signal_handler, raising_signal_handler, SigHup, SigTerm
 from .logger import create_logger, setup_logging
 logger = create_logger()
@@ -2075,7 +2075,7 @@ class Archiver:
         check_extension_modules()
         if is_slow_msgpack():
             logger.warning("Using a pure-python msgpack! This will result in lower performance.")
-        return func(args)
+        return set_ec(func(args))
 
 
 def sig_info_handler(sig_no, stack):  # pragma: no cover

borg/helpers.py

@@ -45,6 +45,26 @@ EXIT_WARNING = 1  # reached normal end of operation, but there were issues
 EXIT_ERROR = 2  # terminated abruptly, did not reach end of operation
 
 
+'''
+The global exit_code variable is used so that modules other than archiver can increase the program exit code if a
+warning or error occured during their operation. This is different from archiver.exit_code, which is only accessible
+from the archiver object.
+'''
+exit_code = EXIT_SUCCESS
+
+
+def set_ec(ec):
+    '''
+    Sets the exit code of the program, if an exit code higher or equal than this is set, this does nothing. This
+    makes EXIT_ERROR override EXIT_WARNING, etc..
+
+    ec: exit code to set
+    '''
+    global exit_code
+    exit_code = max(exit_code, ec)
+    return exit_code
+
+
 class Error(Exception):
     """Error base class"""
 

borg/testsuite/archiver.py

@@ -19,7 +19,7 @@ from hashlib import sha256
 import msgpack
 import pytest
 
-from .. import xattr
+from .. import xattr, helpers
 from ..archive import Archive, ChunkBuffer, CHUNK_MAX_EXP, flags_noatime, flags_normal
 from ..archiver import Archiver
 from ..cache import Cache
@@ -68,6 +68,7 @@ def exec_cmd(*args, archiver=None, fork=False, exe=None, **kw):
             if archiver is None:
                 archiver = Archiver()
             archiver.exit_code = EXIT_SUCCESS
+            helpers.exit_code = EXIT_SUCCESS
             args = archiver.parse_args(list(args))
             ret = archiver.run(args)
             return ret, output.getvalue()