text: // Copyright 2014 The Chromium Authors. All rights reserved.
  // Use of this source code is governed by a BSD-style license that can be
  // found in the LICENSE file.
  //
  // This file contains the default options for various compiler-based dynamic
  // tools.
  
  #include "build/build_config.h"
  
  #if defined(ADDRESS_SANITIZER) && defined(OS_MACOSX)
  #include <crt_externs.h>  // for _NSGetArgc, _NSGetArgv
  #include <string.h>
  #endif  // ADDRESS_SANITIZER && OS_MACOSX
  
  #if defined(ADDRESS_SANITIZER) || defined(LEAK_SANITIZER) ||  \
      defined(MEMORY_SANITIZER) || defined(THREAD_SANITIZER) || \
      defined(UNDEFINED_SANITIZER)
  // Functions returning default options are declared weak in the tools' runtime
  // libraries. To make the linker pick the strong replacements for those
  // functions from this module, we explicitly force its inclusion by passing
  // -Wl,-u_sanitizer_options_link_helper
  extern "C"
  void _sanitizer_options_link_helper() { }
  
  // The callbacks we define here will be called from the sanitizer runtime, but
  // aren't referenced from the Chrome executable. We must ensure that those
  // callbacks are not sanitizer-instrumented, and that they aren't stripped by
  // the linker.
  #define SANITIZER_HOOK_ATTRIBUTE                                           \
    extern "C"                                                               \
    __attribute__((no_sanitize("address", "memory", "thread", "undefined"))) \
    __attribute__((visibility("default")))                                   \
    __attribute__((used))
  #endif
  
  #if defined(ADDRESS_SANITIZER)
  // Default options for AddressSanitizer in various configurations:
  //   malloc_context_size=5 - limit the size of stack traces collected by ASan
  //     for each malloc/free by 5 frames. These stack traces tend to accumulate
  //     very fast in applications using JIT (v8 in Chrome's case), see
  //     https://code.google.com/p/address-sanitizer/issues/detail?id=177
  //   symbolize=1 - enable in-process symbolization.
  //   legacy_pthread_cond=1 - run in the libpthread 2.2.5 compatibility mode to
  //     work around libGL.so using the obsolete API, see
  //     http://crbug.com/341805. This may break if pthread_cond_t objects are
  //     accessed by both instrumented and non-instrumented binaries (e.g. if
  //     they reside in shared memory). This option is going to be deprecated in
  //     upstream AddressSanitizer and must not be used anywhere except the
  //     official builds.
  //   check_printf=1 - check the memory accesses to printf (and other formatted
  //     output routines) arguments.
  //   use_sigaltstack=1 - handle signals on an alternate signal stack. Useful
  //     for stack overflow detection.
  //   strip_path_prefix=/../../ - prefixes up to and including this
  //     substring will be stripped from source file paths in symbolized reports
  //   fast_unwind_on_fatal=1 - use the fast (frame-pointer-based) stack unwinder
  //     to print error reports. V8 doesn't generate debug info for the JIT code,
  //     so the slow unwinder may not work properly.
  //   detect_stack_use_after_return=1 - use fake stack to delay the reuse of
  //     stack allocations and detect stack-use-after-return errors.
  #if defined(OS_LINUX)
  #if defined(GOOGLE_CHROME_BUILD)
  // Default AddressSanitizer options for the official build. These do not affect
  // tests on buildbots (which don't set GOOGLE_CHROME_BUILD) or non-official
  // Chromium builds.
  const char kAsanDefaultOptions[] =
      "legacy_pthread_cond=1 malloc_context_size=5 "
      "symbolize=1 check_printf=1 use_sigaltstack=1 detect_leaks=0 "
      "strip_path_prefix=/../../ fast_unwind_on_fatal=1";
  #else
  // Default AddressSanitizer options for buildbots and non-official builds.
  const char *kAsanDefaultOptions =
      "symbolize=1 check_printf=1 use_sigaltstack=1 "
      "detect_leaks=0 strip_path_prefix=/../../ fast_unwind_on_fatal=1 "
      "detect_stack_use_after_return=1 ";
  #endif  // GOOGLE_CHROME_BUILD
  
  #elif defined(OS_MACOSX)
  const char *kAsanDefaultOptions =
      "check_printf=1 use_sigaltstack=1 "
      "strip_path_prefix=/../../ fast_unwind_on_fatal=1 "
      "detect_stack_use_after_return=1 detect_odr_violation=0 ";
  static const char kNaClDefaultOptions[] = "handle_segv=0";
  static const char kNaClFlag[] = "--type=nacl-loader";
  #endif  // OS_LINUX
  
  #if defined(OS_LINUX) || defined(OS_MACOSX)
  SANITIZER_HOOK_ATTRIBUTE const char *__asan_default_options() {
  #if defined(OS_MACOSX)
    char*** argvp = _NSGetArgv();
    int* argcp = _NSGetArgc();
    if (!argvp || !argcp) return kAsanDefaultOptions;
    char** argv = *argvp;
    int argc = *argcp;
    for (int i = 0; i < argc; ++i) {
      if (strcmp(argv[i], kNaClFlag) == 0) {
        return kNaClDefaultOptions;
      }
    }
  #endif
    return kAsanDefaultOptions;
  }
  
  extern "C" char kASanDefaultSuppressions[];
  
  SANITIZER_HOOK_ATTRIBUTE const char *__asan_default_suppressions() {
    return kASanDefaultSuppressions;
  }
  #endif  // OS_LINUX || OS_MACOSX
  #endif  // ADDRESS_SANITIZER
  
  #if defined(THREAD_SANITIZER) && defined(OS_LINUX)
  // Default options for ThreadSanitizer in various configurations:
  //   detect_deadlocks=1 - enable deadlock (lock inversion) detection.
  //   second_deadlock_stack=1 - more verbose deadlock reports.
  //   report_signal_unsafe=0 - do not report async-signal-unsafe functions
  //     called from signal handlers.
  //   report_thread_leaks=0 - do not report unjoined threads at the end of
  //     the program execution.
  //   print_suppressions=1 - print the list of matched suppressions.
  //   history_size=7 - make the history buffer proportional to 2^7 (the maximum
  //     value) to keep more stack traces.
  //   strip_path_prefix=/../../ - prefixes up to and including this
  //     substring will be stripped from source file paths in symbolized reports.
  const char kTsanDefaultOptions[] =
      "detect_deadlocks=1 second_deadlock_stack=1 report_signal_unsafe=0 "
      "report_thread_leaks=0 print_suppressions=1 history_size=7 "
      "strict_memcmp=0 strip_path_prefix=/../../ ";
  
  SANITIZER_HOOK_ATTRIBUTE const char *__tsan_default_options() {
    return kTsanDefaultOptions;
  }
  
  extern "C" char kTSanDefaultSuppressions[];
  
  SANITIZER_HOOK_ATTRIBUTE const char *__tsan_default_suppressions() {
    return kTSanDefaultSuppressions;
  }
  
  #endif  // THREAD_SANITIZER && OS_LINUX
  
  #if defined(MEMORY_SANITIZER)
  // Default options for MemorySanitizer:
  //   intercept_memcmp=0 - do not detect uninitialized memory in memcmp() calls.
  //     Pending cleanup, see http://crbug.com/523428
  //   strip_path_prefix=/../../ - prefixes up to and including this
  //     substring will be stripped from source file paths in symbolized reports.
  const char kMsanDefaultOptions[] =
      "intercept_memcmp=0 strip_path_prefix=/../../ ";
  
  SANITIZER_HOOK_ATTRIBUTE const char *__msan_default_options() {
    return kMsanDefaultOptions;
  }
  
  #endif  // MEMORY_SANITIZER
  
  #if defined(LEAK_SANITIZER)
  // Default options for LeakSanitizer:
  //   print_suppressions=1 - print the list of matched suppressions.
  //   strip_path_prefix=/../../ - prefixes up to and including this
  //     substring will be stripped from source file paths in symbolized reports.
  const char kLsanDefaultOptions[] =
      "print_suppressions=1 strip_path_prefix=/../../ ";
  
  SANITIZER_HOOK_ATTRIBUTE const char *__lsan_default_options() {
    return kLsanDefaultOptions;
  }
  
  extern "C" char kLSanDefaultSuppressions[];
  
  SANITIZER_HOOK_ATTRIBUTE const char *__lsan_default_suppressions() {
    return kLSanDefaultSuppressions;
  }
  
  #endif  // LEAK_SANITIZER
  
  #if defined(UNDEFINED_SANITIZER)
  // Default options for UndefinedBehaviorSanitizer:
  //   print_stacktrace=1 - print the stacktrace when UBSan reports an error.
  const char kUbsanDefaultOptions[] = "print_stacktrace=1";
  
  SANITIZER_HOOK_ATTRIBUTE const char* __ubsan_default_options() {
    return kUbsanDefaultOptions;
  }
  
  #endif  // UNDEFINED_SANITIZER
  