diff options
| -rw-r--r-- | lib/fuzzer/CMakeLists.txt | 2 | ||||
| -rw-r--r-- | lib/fuzzer/FuzzerExtFunctionsWeakAlias.cpp | 56 | ||||
| -rw-r--r-- | lib/fuzzer/FuzzerExtFunctionsWindows.cpp | 83 |
3 files changed, 84 insertions, 57 deletions
diff --git a/lib/fuzzer/CMakeLists.txt b/lib/fuzzer/CMakeLists.txt index ad736c109..caea9734f 100644 --- a/lib/fuzzer/CMakeLists.txt +++ b/lib/fuzzer/CMakeLists.txt @@ -3,8 +3,8 @@ set(LIBFUZZER_SOURCES FuzzerDataFlowTrace.cpp FuzzerDriver.cpp FuzzerExtFunctionsDlsym.cpp - FuzzerExtFunctionsWeakAlias.cpp FuzzerExtFunctionsWeak.cpp + FuzzerExtFunctionsWindows.cpp FuzzerExtraCounters.cpp FuzzerIO.cpp FuzzerIOPosix.cpp diff --git a/lib/fuzzer/FuzzerExtFunctionsWeakAlias.cpp b/lib/fuzzer/FuzzerExtFunctionsWeakAlias.cpp deleted file mode 100644 index e10f7b4dc..000000000 --- a/lib/fuzzer/FuzzerExtFunctionsWeakAlias.cpp +++ /dev/null @@ -1,56 +0,0 @@ -//===- FuzzerExtFunctionsWeakAlias.cpp - Interface to external functions --===// -// -// The LLVM Compiler Infrastructure -// -// This file is distributed under the University of Illinois Open Source -// License. See LICENSE.TXT for details. -// -//===----------------------------------------------------------------------===// -// Implementation using weak aliases. Works for Windows. -//===----------------------------------------------------------------------===// -#include "FuzzerDefs.h" -#if LIBFUZZER_WINDOWS - -#include "FuzzerExtFunctions.h" -#include "FuzzerIO.h" - -using namespace fuzzer; - -extern "C" { -// Declare these symbols as weak to allow them to be optionally defined. -#define EXT_FUNC(NAME, RETURN_TYPE, FUNC_SIG, WARN) \ - RETURN_TYPE NAME##Def FUNC_SIG { \ - Printf("ERROR: Function \"%s\" not defined.\n", #NAME); \ - exit(1); \ - } \ - RETURN_TYPE NAME FUNC_SIG __attribute__((weak, alias(#NAME "Def"))); - -#include "FuzzerExtFunctions.def" - -#undef EXT_FUNC -} - -template <typename T> -static T *GetFnPtr(T *Fun, T *FunDef, const char *FnName, bool WarnIfMissing) { - if (Fun == FunDef) { - if (WarnIfMissing) - Printf("WARNING: Failed to find function \"%s\".\n", FnName); - return nullptr; - } - return Fun; -} - -namespace fuzzer { - -ExternalFunctions::ExternalFunctions() { -#define EXT_FUNC(NAME, RETURN_TYPE, FUNC_SIG, WARN) \ - this->NAME = GetFnPtr<decltype(::NAME)>(::NAME, ::NAME##Def, #NAME, WARN); - -#include "FuzzerExtFunctions.def" - -#undef EXT_FUNC -} - -} // namespace fuzzer - -#endif // LIBFUZZER_WINDOWS diff --git a/lib/fuzzer/FuzzerExtFunctionsWindows.cpp b/lib/fuzzer/FuzzerExtFunctionsWindows.cpp new file mode 100644 index 000000000..b01871439 --- /dev/null +++ b/lib/fuzzer/FuzzerExtFunctionsWindows.cpp @@ -0,0 +1,83 @@ +//=== FuzzerExtWindows.cpp - Interface to external functions --------------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// Implementation of FuzzerExtFunctions for Windows. Uses alternatename when +// compiled with MSVC. Uses weak aliases when compiled with clang. Unfortunately +// the method each compiler supports is not supported by the other. +//===----------------------------------------------------------------------===// +#include "FuzzerDefs.h" +#if LIBFUZZER_WINDOWS + +#include "FuzzerExtFunctions.h" +#include "FuzzerIO.h" + +using namespace fuzzer; + +// Intermediate macro to ensure the parameter is expanded before stringified. +#define STRINGIFY_(A) #A +#define STRINGIFY(A) STRINGIFY_(A) + +#if LIBFUZZER_MSVC +// Copied from compiler-rt/lib/sanitizer_common/sanitizer_win_defs.h +#if defined(_M_IX86) || defined(__i386__) +#define WIN_SYM_PREFIX "_" +#else +#define WIN_SYM_PREFIX +#endif + +// Declare external functions as having alternativenames, so that we can +// determine if they are not defined. +#define EXTERNAL_FUNC(Name, Default) \ + __pragma(comment(linker, "/alternatename:" WIN_SYM_PREFIX STRINGIFY( \ + Name) "=" WIN_SYM_PREFIX STRINGIFY(Default))) +#else +// Declare external functions as weak to allow them to default to a specified +// function if not defined explicitly. We must use weak symbols because clang's +// support for alternatename is not 100%, see +// https://bugs.llvm.org/show_bug.cgi?id=40218 for more details. +#define EXTERNAL_FUNC(Name, Default) \ + __attribute__((weak, alias(STRINGIFY(Default)))) +#endif // LIBFUZZER_MSVC + +extern "C" { +#define EXT_FUNC(NAME, RETURN_TYPE, FUNC_SIG, WARN) \ + RETURN_TYPE NAME##Def FUNC_SIG { \ + Printf("ERROR: Function \"%s\" not defined.\n", #NAME); \ + exit(1); \ + } \ + EXTERNAL_FUNC(NAME, NAME##Def) RETURN_TYPE NAME FUNC_SIG; + +#include "FuzzerExtFunctions.def" + +#undef EXT_FUNC +} + +template <typename T> +static T *GetFnPtr(T *Fun, T *FunDef, const char *FnName, bool WarnIfMissing) { + if (Fun == FunDef) { + if (WarnIfMissing) + Printf("WARNING: Failed to find function \"%s\".\n", FnName); + return nullptr; + } + return Fun; +} + +namespace fuzzer { + +ExternalFunctions::ExternalFunctions() { +#define EXT_FUNC(NAME, RETURN_TYPE, FUNC_SIG, WARN) \ + this->NAME = GetFnPtr<decltype(::NAME)>(::NAME, ::NAME##Def, #NAME, WARN); + +#include "FuzzerExtFunctions.def" + +#undef EXT_FUNC +} + +} // namespace fuzzer + +#endif // LIBFUZZER_WINDOWS |