[sanitizer] Remove empty Symbolizer PrepareForSandboxing

Summary:
`Symbolizer::PrepareForSandboxing` is empty for all platforms and apparently
has been for a while (D10213). Remove it, and shuffle things around so that the
platform specific code is now in `PlatformPrepareForSandboxing`.

This allows to have one less symbolizer dependency in a common file, which
helps for the upcoming split.

Also remove `SymbolizerPrepareForSandboxing` in tsan_go which appears to not
be used anywhere.

Reviewers: alekseyshl, eugenis, dvyukov, mcgrathr

Reviewed By: alekseyshl

Subscribers: kubamracek, delcypher, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D44953

llvm-svn: 329094

compiler-rt/lib/sanitizer_common/sanitizer_common.h

@@ -281,7 +281,7 @@ void SetStackSizeLimitInBytes(uptr limit);
 bool AddressSpaceIsUnlimited();
 void SetAddressSpaceUnlimited();
 void AdjustStackSize(void *attr);
-void PrepareForSandboxing(__sanitizer_sandbox_arguments *args);
+void PlatformPrepareForSandboxing(__sanitizer_sandbox_arguments *args);
 void SetSandboxingCallback(void (*f)());
 
 void InitializeCoverage(bool enabled, const char *coverage_dir);

compiler-rt/lib/sanitizer_common/sanitizer_common_libcdep.cc

@@ -59,11 +59,6 @@ bool ColorizeReports() {
          (internal_strcmp(flag, "auto") == 0 && ReportSupportsColors());
 }
 
-static void (*sandboxing_callback)();
-void SetSandboxingCallback(void (*f)()) {
-  sandboxing_callback = f;
-}
-
 void ReportErrorSummary(const char *error_type, const StackTrace *stack,
                         const char *alt_tool_name) {
 #if !SANITIZER_GO
@@ -369,11 +364,16 @@ void ScopedErrorReportLock::CheckLocked() {
   CommonSanitizerReportMutex.CheckLocked();
 }
 
+static void (*sandboxing_callback)();
+void SetSandboxingCallback(void (*f)()) {
+  sandboxing_callback = f;
+}
+
 }  // namespace __sanitizer
 
 SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_sandbox_on_notify,
                              __sanitizer_sandbox_arguments *args) {
-  __sanitizer::PrepareForSandboxing(args);
+  __sanitizer::PlatformPrepareForSandboxing(args);
   if (__sanitizer::sandboxing_callback)
     __sanitizer::sandboxing_callback();
 }

compiler-rt/lib/sanitizer_common/sanitizer_fuchsia.cc

@@ -89,7 +89,7 @@ void GetThreadStackTopAndBottom(bool, uptr *stack_top, uptr *stack_bottom) {
 }
 
 void MaybeReexec() {}
-void PrepareForSandboxing(__sanitizer_sandbox_arguments *args) {}
+void PlatformPrepareForSandboxing(__sanitizer_sandbox_arguments *args) {}
 void DisableCoreDumperIfNecessary() {}
 void InstallDeadlySignalHandlers(SignalHandlerType handler) {}
 void StartReportDeadlySignal() {}

compiler-rt/lib/sanitizer_common/sanitizer_posix_libcdep.cc

@@ -24,8 +24,6 @@
 #include "sanitizer_platform_limits_solaris.h"
 #include "sanitizer_posix.h"
 #include "sanitizer_procmaps.h"
-#include "sanitizer_stacktrace.h"
-#include "sanitizer_symbolizer.h"
 
 #include <errno.h>
 #include <fcntl.h>
@@ -292,16 +290,12 @@ bool IsAccessibleMemoryRange(uptr beg, uptr size) {
   return result;
 }
 
-void PrepareForSandboxing(__sanitizer_sandbox_arguments *args) {
+void PlatformPrepareForSandboxing(__sanitizer_sandbox_arguments *args) {
   // Some kinds of sandboxes may forbid filesystem access, so we won't be able
   // to read the file mappings from /proc/self/maps. Luckily, neither the
   // process will be able to load additional libraries, so it's fine to use the
   // cached mappings.
   MemoryMappingLayout::CacheMemoryMappings();
-  // Same for /proc/self/exe in the symbolizer.
-#if !SANITIZER_GO
-  Symbolizer::GetOrInit()->PrepareForSandboxing();
-#endif
 }
 
 #if SANITIZER_ANDROID || SANITIZER_GO

compiler-rt/lib/sanitizer_common/sanitizer_symbolizer.h

@@ -107,7 +107,6 @@ class Symbolizer final {
   void Flush();
   // Attempts to demangle the provided C++ mangled name.
   const char *Demangle(const char *name);
-  void PrepareForSandboxing();
 
   // Allow user to install hooks that would be called before/after Symbolizer
   // does the actual file/line info fetching. Specific sanitizers may need this
@@ -158,7 +157,6 @@ class Symbolizer final {
 
   // Platform-specific default demangler, must not return nullptr.
   const char *PlatformDemangle(const char *name);
-  void PlatformPrepareForSandboxing();
 
   static Symbolizer *symbolizer_;
   static StaticSpinMutex init_mu_;

compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_libcdep.cc

@@ -145,11 +145,6 @@ const char *Symbolizer::Demangle(const char *name) {
   return PlatformDemangle(name);
 }
 
-void Symbolizer::PrepareForSandboxing() {
-  BlockingMutexLock l(&mu_);
-  PlatformPrepareForSandboxing();
-}
-
 bool Symbolizer::FindModuleNameAndOffsetForAddress(uptr address,
                                                    const char **module_name,
                                                    uptr *module_offset,

compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_posix_libcdep.cc

@@ -445,8 +445,6 @@ const char *Symbolizer::PlatformDemangle(const char *name) {
   return DemangleSwiftAndCXX(name);
 }
 
-void Symbolizer::PlatformPrepareForSandboxing() {}
-
 static SymbolizerTool *ChooseExternalSymbolizer(LowLevelAllocator *allocator) {
   const char *path = common_flags()->external_symbolizer_path;
   const char *binary_name = path ? StripModuleName(path) : "";

compiler-rt/lib/sanitizer_common/sanitizer_symbolizer_win.cc

@@ -176,10 +176,6 @@ const char *Symbolizer::PlatformDemangle(const char *name) {
   return name;
 }
 
-void Symbolizer::PlatformPrepareForSandboxing() {
-  // Do nothing.
-}
-
 namespace {
 struct ScopedHandle {
   ScopedHandle() : h_(nullptr) {}

compiler-rt/lib/sanitizer_common/sanitizer_win.cc

@@ -467,8 +467,7 @@ void ReExec() {
   UNIMPLEMENTED();
 }
 
-void PrepareForSandboxing(__sanitizer_sandbox_arguments *args) {
-}
+void PlatformPrepareForSandboxing(__sanitizer_sandbox_arguments *args) {}
 
 bool StackSizeIsUnlimited() {
   UNIMPLEMENTED();

compiler-rt/lib/tsan/go/tsan_go.cc

@@ -282,11 +282,3 @@ void __tsan_report_count(u64 *pn) {
 
 }  // extern "C"
 }  // namespace __tsan
-
-namespace __sanitizer {
-
-void SymbolizerPrepareForSandboxing() {
-  // Nothing to do here for Go.
-}
-
-}  // namespace __sanitizer