1//===-- ubsan_flags.cpp ---------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// Runtime flags for UndefinedBehaviorSanitizer.
10//
11//===----------------------------------------------------------------------===//
12
13#include "ubsan_platform.h"
14#if CAN_SANITIZE_UB
15#include "ubsan_flags.h"
16#include "sanitizer_common/sanitizer_common.h"
17#include "sanitizer_common/sanitizer_flags.h"
18#include "sanitizer_common/sanitizer_flag_parser.h"
19
20#include <stdlib.h>
21
22namespace __ubsan {
23
24static const char *GetFlag(const char *flag) {
25  // We cannot call getenv() from inside a preinit array initializer
26  if (SANITIZER_CAN_USE_PREINIT_ARRAY) {
27    return GetEnv(flag);
28  } else {
29    return getenv(flag);
30  }
31}
32
33Flags ubsan_flags;
34
35void Flags::SetDefaults() {
36#define UBSAN_FLAG(Type, Name, DefaultValue, Description) Name = DefaultValue;
37#include "ubsan_flags.inc"
38#undef UBSAN_FLAG
39}
40
41void RegisterUbsanFlags(FlagParser *parser, Flags *f) {
42#define UBSAN_FLAG(Type, Name, DefaultValue, Description) \
43  RegisterFlag(parser, #Name, Description, &f->Name);
44#include "ubsan_flags.inc"
45#undef UBSAN_FLAG
46}
47
48void InitializeFlags() {
49  SetCommonFlagsDefaults();
50  {
51    CommonFlags cf;
52    cf.CopyFrom(*common_flags());
53    cf.external_symbolizer_path = GetFlag("UBSAN_SYMBOLIZER_PATH");
54    OverrideCommonFlags(cf);
55  }
56
57  Flags *f = flags();
58  f->SetDefaults();
59
60  FlagParser parser;
61  RegisterCommonFlags(&parser);
62  RegisterUbsanFlags(&parser, f);
63
64  // Override from user-specified string.
65  parser.ParseString(__ubsan_default_options());
66  // Override from environment variable.
67  parser.ParseStringFromEnv("UBSAN_OPTIONS");
68  InitializeCommonFlags();
69  if (Verbosity()) ReportUnrecognizedFlags();
70
71  if (common_flags()->help) parser.PrintFlagDescriptions();
72}
73
74}  // namespace __ubsan
75
76SANITIZER_INTERFACE_WEAK_DEF(const char *, __ubsan_default_options, void) {
77  return "";
78}
79
80#endif  // CAN_SANITIZE_UB
81