libsanitizer/ubsan/ubsan_monitor.cc

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