contrib/compiler-rt/lib/ubsan/ubsan_monitor.cc

   1 //===-- ubsan_monitor.cc ----------------------------------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // Hooks which allow a monitor process to inspect UBSan's diagnostics.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #include "ubsan_monitor.h"
  15
  16 using namespace __ubsan;
  17
  18 UndefinedBehaviorReport::UndefinedBehaviorReport(const char *IssueKind,
  19                                                  Location &Loc,
  20                                                  InternalScopedString &Msg)
  21     : IssueKind(IssueKind), Loc(Loc), Buffer(Msg.length() + 1) {
  22   // We have the common sanitizer reporting lock, so it's safe to register a
  23   // new UB report.
  24   RegisterUndefinedBehaviorReport(this);
  25
  26   // Make a copy of the diagnostic.
  27   Buffer.append("%s", Msg.data());
  28
  29   // Let the monitor know that a report is available.
  30   __ubsan_on_report();
  31 }
  32
  33 static UndefinedBehaviorReport *CurrentUBR;
  34
  35 void __ubsan::RegisterUndefinedBehaviorReport(UndefinedBehaviorReport *UBR) {
  36   CurrentUBR = UBR;
  37 }
  38
  39 SANITIZER_WEAK_DEFAULT_IMPL
  40 void __ubsan::__ubsan_on_report(void) {}
  41
  42 void __ubsan::__ubsan_get_current_report_data(const char **OutIssueKind,
  43                                               const char **OutMessage,
  44                                               const char **OutFilename,
  45                                               unsigned *OutLine,
  46                                               unsigned *OutCol,
  47                                               char **OutMemoryAddr) {
  48   if (!OutIssueKind || !OutMessage || !OutFilename || !OutLine || !OutCol ||
  49       !OutMemoryAddr)
  50     UNREACHABLE("Invalid arguments passed to __ubsan_get_current_report_data");
  51
  52   InternalScopedString &Buf = CurrentUBR->Buffer;
  53
  54   // Ensure that the first character of the diagnostic text can't start with a
  55   // lowercase letter.
  56   char FirstChar = Buf.data()[0];
  57   if (FirstChar >= 'a' && FirstChar <= 'z')
  58     Buf.data()[0] = FirstChar - 'a' + 'A';
  59
  60   *OutIssueKind = CurrentUBR->IssueKind;
  61   *OutMessage = Buf.data();
  62   if (!CurrentUBR->Loc.isSourceLocation()) {
  63     *OutFilename = "<unknown>";
  64     *OutLine = *OutCol = 0;
  65   } else {
  66     SourceLocation SL = CurrentUBR->Loc.getSourceLocation();
  67     *OutFilename = SL.getFilename();
  68     *OutLine = SL.getLine();
  69     *OutCol = SL.getColumn();
  70   }
  71
  72   if (CurrentUBR->Loc.isMemoryLocation())
  73     *OutMemoryAddr = (char *)CurrentUBR->Loc.getMemoryLocation();
  74   else
  75     *OutMemoryAddr = nullptr;
  76 }