//===-- sanitizer_symbolizer_win.cc ---------------------------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is shared between AddressSanitizer and ThreadSanitizer
// run-time libraries.
// Windows-specific implementation of symbolizer parts.
//===----------------------------------------------------------------------===//
#include "sanitizer_platform.h"
#if SANITIZER_WINDOWS
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#include <dbghelp.h>
#pragma comment(lib, "dbghelp.lib")
#include "sanitizer_symbolizer_internal.h"
namespace __sanitizer {
namespace {
class WinSymbolizerTool : public SymbolizerTool {
public:
bool SymbolizePC(uptr addr, SymbolizedStack *stack) override;
bool SymbolizeData(uptr addr, DataInfo *info) override {
return false;
}
const char *Demangle(const char *name) override;
};
bool is_dbghelp_initialized = false;
bool TrySymInitialize() {
SymSetOptions(SYMOPT_DEFERRED_LOADS | SYMOPT_UNDNAME | SYMOPT_LOAD_LINES);
return SymInitialize(GetCurrentProcess(), 0, TRUE);
// FIXME: We don't call SymCleanup() on exit yet - should we?
}
// Initializes DbgHelp library, if it's not yet initialized. Calls to this
// function should be synchronized with respect to other calls to DbgHelp API
// (e.g. from WinSymbolizerTool).
void InitializeDbgHelpIfNeeded() {
if (is_dbghelp_initialized)
return;
if (!TrySymInitialize()) {
// OK, maybe the client app has called SymInitialize already.
// That's a bit unfortunate for us as all the DbgHelp functions are
// single-threaded and we can't coordinate with the app.
// FIXME: Can we stop the other threads at this point?
// Anyways, we have to reconfigure stuff to make sure that SymInitialize
// has all the appropriate options set.
// Cross our fingers and reinitialize DbgHelp.
Report("*** WARNING: Failed to initialize DbgHelp! ***\n");
Report("*** Most likely this means that the app is already ***\n");
Report("*** using DbgHelp, possibly with incompatible flags. ***\n");
Report("*** Due to technical reasons, symbolization might crash ***\n");
Report("*** or produce wrong results. ***\n");
SymCleanup(GetCurrentProcess());
TrySymInitialize();
}
is_dbghelp_initialized = true;
// When an executable is run from a location different from the one where it
// was originally built, we may not see the nearby PDB files.
// To work around this, let's append the directory of the main module
// to the symbol search path. All the failures below are not fatal.
const size_t kSymPathSize = 2048;
static wchar_t path_buffer[kSymPathSize + 1 + MAX_PATH];
if (!SymGetSearchPathW(GetCurrentProcess(), path_buffer, kSymPathSize)) {
Report("*** WARNING: Failed to SymGetSearchPathW ***\n");
return;
}
size_t sz = wcslen(path_buffer);
if (sz) {
CHECK_EQ(0, wcscat_s(path_buffer, L";"));
sz++;
}
DWORD res = GetModuleFileNameW(NULL, path_buffer + sz, MAX_PATH);
if (res == 0 || res == MAX_PATH) {
Report("*** WARNING: Failed to getting the EXE directory ***\n");
return;
}
// Write the zero character in place of the last backslash to get the
// directory of the main module at the end of path_buffer.
wchar_t *last_bslash = wcsrchr(path_buffer + sz, L'\\');
CHECK_NE(last_bslash, 0);
*last_bslash = L'\0';
if (!SymSetSearchPathW(GetCurrentProcess(), path_buffer)) {
Report("*** WARNING: Failed to SymSetSearchPathW\n");
return;
}
}
} // namespace
bool WinSymbolizerTool::SymbolizePC(uptr addr, SymbolizedStack *frame) {
InitializeDbgHelpIfNeeded();
// See http://msdn.microsoft.com/en-us/library/ms680578(VS.85).aspx
char buffer[sizeof(SYMBOL_INFO) + MAX_SYM_NAME * sizeof(CHAR)];
PSYMBOL_INFO symbol = (PSYMBOL_INFO)buffer;
symbol->SizeOfStruct = sizeof(SYMBOL_INFO);
symbol->MaxNameLen = MAX_SYM_NAME;
DWORD64 offset = 0;
BOOL got_objname = SymFromAddr(GetCurrentProcess(),
(DWORD64)addr, &offset, symbol);
if (!got_objname)
return false;
DWORD unused;
IMAGEHLP_LINE64 line_info;
line_info.SizeOfStruct = sizeof(IMAGEHLP_LINE64);
BOOL got_fileline = SymGetLineFromAddr64(GetCurrentProcess(), (DWORD64)addr,
&unused, &line_info);
frame->info.function = internal_strdup(symbol->Name);
frame->info.function_offset = (uptr)offset;
if (got_fileline) {
frame->info.file = internal_strdup(line_info.FileName);
frame->info.line = line_info.LineNumber;
}
// Only consider this a successful symbolization attempt if we got file info.
// Otherwise, try llvm-symbolizer.
return got_fileline;
}
const char *WinSymbolizerTool::Demangle(const char *name) {
CHECK(is_dbghelp_initialized);
static char demangle_buffer[1000];
if (name[0] == '\01' &&
UnDecorateSymbolName(name + 1, demangle_buffer, sizeof(demangle_buffer),
UNDNAME_NAME_ONLY))
return demangle_buffer;
else
return name;
}
const char *Symbolizer::PlatformDemangle(const char *name) {
return name;
}
void Symbolizer::PlatformPrepareForSandboxing() {
// Do nothing.
}
namespace {
struct ScopedHandle {
ScopedHandle() : h_(nullptr) {}
explicit ScopedHandle(HANDLE h) : h_(h) {}
~ScopedHandle() {
if (h_)
::CloseHandle(h_);
}
HANDLE get() { return h_; }
HANDLE *receive() { return &h_; }
HANDLE release() {
HANDLE h = h_;
h_ = nullptr;
return h;
}
HANDLE h_;
};
} // namespace
bool SymbolizerProcess::StartSymbolizerSubprocess() {
// Create inherited pipes for stdin and stdout.
ScopedHandle stdin_read, stdin_write;
ScopedHandle stdout_read, stdout_write;
SECURITY_ATTRIBUTES attrs;
attrs.nLength = sizeof(SECURITY_ATTRIBUTES);
attrs.bInheritHandle = TRUE;
attrs.lpSecurityDescriptor = nullptr;
if (!::CreatePipe(stdin_read.receive(), stdin_write.receive(), &attrs, 0) ||
!::CreatePipe(stdout_read.receive(), stdout_write.receive(), &attrs, 0)) {
VReport(2, "WARNING: %s CreatePipe failed (error code: %d)\n",
SanitizerToolName, path_, GetLastError());
return false;
}
// Don't inherit the writing end of stdin or the reading end of stdout.
if (!SetHandleInformation(stdin_write.get(), HANDLE_FLAG_INHERIT, 0) ||
!SetHandleInformation(stdout_read.get(), HANDLE_FLAG_INHERIT, 0)) {
VReport(2, "WARNING: %s SetHandleInformation failed (error code: %d)\n",
SanitizerToolName, path_, GetLastError());
return false;
}
// Compute the command line. Wrap double quotes around everything.
const char *argv[kArgVMax];
GetArgV(path_, argv);
InternalScopedString command_line(kMaxPathLength * 3);
for (int i = 0; argv[i]; i++) {
const char *arg = argv[i];
int arglen = internal_strlen(arg);
// Check that tool command lines are simple and that complete escaping is
// unnecessary.
CHECK(!internal_strchr(arg, '"') && "quotes in args unsupported");
CHECK(!internal_strstr(arg, "\\\\") &&
"double backslashes in args unsupported");
CHECK(arglen > 0 && arg[arglen - 1] != '\\' &&
"args ending in backslash and empty args unsupported");
command_line.append("\"%s\" ", arg);
}
VReport(3, "Launching symbolizer command: %s\n", command_line.data());
// Launch llvm-symbolizer with stdin and stdout redirected.
STARTUPINFOA si;
memset(&si, 0, sizeof(si));
si.cb = sizeof(si);
si.dwFlags |= STARTF_USESTDHANDLES;
si.hStdInput = stdin_read.get();
si.hStdOutput = stdout_write.get();
PROCESS_INFORMATION pi;
memset(&pi, 0, sizeof(pi));
if (!CreateProcessA(path_, // Executable
command_line.data(), // Command line
nullptr, // Process handle not inheritable
nullptr, // Thread handle not inheritable
TRUE, // Set handle inheritance to TRUE
0, // Creation flags
nullptr, // Use parent's environment block
nullptr, // Use parent's starting directory
&si, &pi)) {
VReport(2, "WARNING: %s failed to create process for %s (error code: %d)\n",
SanitizerToolName, path_, GetLastError());
return false;
}
// Process creation succeeded, so transfer handle ownership into the fields.
input_fd_ = stdout_read.release();
output_fd_ = stdin_write.release();
// The llvm-symbolizer process is responsible for quitting itself when the
// stdin pipe is closed, so we don't need these handles. Close them to prevent
// leaks. If we ever want to try to kill the symbolizer process from the
// parent, we'll want to hang on to these handles.
CloseHandle(pi.hProcess);
CloseHandle(pi.hThread);
return true;
}
static void ChooseSymbolizerTools(IntrusiveList<SymbolizerTool> *list,
LowLevelAllocator *allocator) {
if (!common_flags()->symbolize) {
VReport(2, "Symbolizer is disabled.\n");
return;
}
// Add llvm-symbolizer in case the binary has dwarf.
const char *user_path = common_flags()->external_symbolizer_path;
const char *path =
user_path ? user_path : FindPathToBinary("llvm-symbolizer.exe");
if (path) {
VReport(2, "Using llvm-symbolizer at %spath: %s\n",
user_path ? "user-specified " : "", path);
list->push_back(new(*allocator) LLVMSymbolizer(path, allocator));
} else {
if (user_path && user_path[0] == '\0') {
VReport(2, "External symbolizer is explicitly disabled.\n");
} else {
VReport(2, "External symbolizer is not present.\n");
}
}
// Add the dbghelp based symbolizer.
list->push_back(new(*allocator) WinSymbolizerTool());
}
Symbolizer *Symbolizer::PlatformInit() {
IntrusiveList<SymbolizerTool> list;
list.clear();
ChooseSymbolizerTools(&list, &symbolizer_allocator_);
return new(symbolizer_allocator_) Symbolizer(list);
}
void Symbolizer::LateInitialize() {
Symbolizer::GetOrInit();
}
} // namespace __sanitizer
#endif // _WIN32