1 files changed, 241 insertions, 85 deletions

diff --git a/libsanitizer/sanitizer_common/sanitizer_symbolizer_win.cc b/libsanitizer/sanitizer_common/sanitizer_symbolizer_win.cc
index a1ed4e9a7b7..bb59f803285 100644
--- a/libsanitizer/sanitizer_common/sanitizer_symbolizer_win.cc
+++ b/libsanitizer/sanitizer_common/sanitizer_symbolizer_win.cc
@@ -16,108 +16,264 @@
 #include <dbghelp.h>
 #pragma comment(lib, "dbghelp.lib")
 
-#include "sanitizer_symbolizer.h"
+#include "sanitizer_symbolizer_internal.h"
 
 namespace __sanitizer {
 
-class WinSymbolizer : public Symbolizer {
+namespace {
+
+class WinSymbolizerTool : public SymbolizerTool {
  public:
-  WinSymbolizer() : initialized_(false) {}
-
-  uptr SymbolizePC(uptr addr, AddressInfo *frames, uptr max_frames) {
-    if (max_frames == 0)
-      return 0;
-
-    BlockingMutexLock l(&dbghelp_mu_);
-    if (!initialized_) {
-      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();
-      }
-      initialized_ = true;
-    }
+  bool SymbolizePC(uptr addr, SymbolizedStack *stack) override;
+  bool SymbolizeData(uptr addr, DataInfo *info) override {
+    return false;
+  }
+  const char *Demangle(const char *name) override;
+};
 
-    // 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 0;
-
-    DWORD unused;
-    IMAGEHLP_LINE64 line_info;
-    line_info.SizeOfStruct = sizeof(IMAGEHLP_LINE64);
-    BOOL got_fileline = SymGetLineFromAddr64(GetCurrentProcess(), (DWORD64)addr,
-                                             &unused, &line_info);
-    AddressInfo *info = &frames[0];
-    info->Clear();
-    info->function = internal_strdup(symbol->Name);
-    info->function_offset = (uptr)offset;
-    if (got_fileline) {
-      info->file = internal_strdup(line_info.FileName);
-      info->line = line_info.LineNumber;
-    }
+bool is_dbghelp_initialized = false;
 
-    IMAGEHLP_MODULE64 mod_info;
-    internal_memset(&mod_info, 0, sizeof(mod_info));
-    mod_info.SizeOfStruct = sizeof(mod_info);
-    if (SymGetModuleInfo64(GetCurrentProcess(), addr, &mod_info))
-      info->FillAddressAndModuleInfo(addr, mod_info.ImageName,
-                                     addr - (uptr)mod_info.BaseOfImage);
-    return 1;
-  }
+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?
+}
 
-  bool CanReturnFileLineInfo() {
-    return true;
+// 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;
 
-  const char *Demangle(const char *name) {
-    CHECK(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;
+  // 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;
+  }
+}
 
-  // FIXME: Implement GetModuleNameAndOffsetForPC().
+}  // namespace
 
- private:
-  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?
+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;
+}
 
-  // All DbgHelp functions are single threaded, so we should use a mutex to
-  // serialize accesses.
-  BlockingMutex dbghelp_mu_;
-  bool initialized_;
+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() {
-  static bool called_once = false;
-  CHECK(!called_once && "Shouldn't create more than one symbolizer");
-  called_once = true;
-  return new(symbolizer_allocator_) WinSymbolizer();
+  IntrusiveList<SymbolizerTool> list;
+  list.clear();
+  ChooseSymbolizerTools(&list, &symbolizer_allocator_);
+
+  return new(symbolizer_allocator_) Symbolizer(list);
 }
 
 }  // namespace __sanitizer