7 files changed, 72 insertions, 36 deletions

diff --git a/libbacktrace/BacktraceCurrent.cpp b/libbacktrace/BacktraceCurrent.cpp
index b7190e256..fd1f4da7b 100644
--- a/libbacktrace/BacktraceCurrent.cpp
+++ b/libbacktrace/BacktraceCurrent.cpp
@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+#define _GNU_SOURCE 1
 #include <errno.h>
 #include <stdint.h>
 #include <string.h>
@@ -73,6 +74,16 @@ bool BacktraceCurrent::Unwind(size_t num_ignore_frames, ucontext_t* ucontext) {
   return UnwindFromContext(num_ignore_frames, nullptr);
 }
 
+bool BacktraceCurrent::DiscardFrame(const backtrace_frame_data_t& frame) {
+  if (BacktraceMap::IsValid(frame.map)) {
+    const std::string library = basename(frame.map.name.c_str());
+    if (library == "libunwind.so" || library == "libbacktrace.so") {
+      return true;
+    }
+  }
+  return false;
+}
+
 static pthread_mutex_t g_sigaction_mutex = PTHREAD_MUTEX_INITIALIZER;
 
 static void SignalHandler(int, siginfo_t*, void* sigcontext) {
diff --git a/libbacktrace/BacktraceCurrent.h b/libbacktrace/BacktraceCurrent.h
index 81ea81d5a..8aad36d00 100644
--- a/libbacktrace/BacktraceCurrent.h
+++ b/libbacktrace/BacktraceCurrent.h
@@ -46,6 +46,9 @@ public:
 
   bool Unwind(size_t num_ignore_frames, ucontext_t* ucontext) override;
 
+protected:
+  bool DiscardFrame(const backtrace_frame_data_t& frame);
+
 private:
   bool UnwindThread(size_t num_ignore_frames);
 
diff --git a/libbacktrace/UnwindCurrent.cpp b/libbacktrace/UnwindCurrent.cpp
index 12e289095..67e583f08 100644
--- a/libbacktrace/UnwindCurrent.cpp
+++ b/libbacktrace/UnwindCurrent.cpp
@@ -99,25 +99,30 @@ bool UnwindCurrent::UnwindFromContext(size_t num_ignore_frames, ucontext_t* ucon
       break;
     }
 
-    if (num_ignore_frames == 0) {
-      frames_.resize(num_frames+1);
-      backtrace_frame_data_t* frame = &frames_.at(num_frames);
-      frame->num = num_frames;
-      frame->pc = static_cast<uintptr_t>(pc);
-      frame->sp = static_cast<uintptr_t>(sp);
-      frame->stack_size = 0;
+    frames_.resize(num_frames+1);
+    backtrace_frame_data_t* frame = &frames_.at(num_frames);
+    frame->num = num_frames;
+    frame->pc = static_cast<uintptr_t>(pc);
+    frame->sp = static_cast<uintptr_t>(sp);
+    frame->stack_size = 0;
 
-      if (num_frames > 0) {
-        // Set the stack size for the previous frame.
-        backtrace_frame_data_t* prev = &frames_.at(num_frames-1);
-        prev->stack_size = frame->sp - prev->sp;
+    FillInMap(frame->pc, &frame->map);
+    // Check to see if we should skip this frame because it's coming
+    // from within the library, and we are doing a local unwind.
+    if (ucontext != nullptr || num_frames != 0 || !DiscardFrame(*frame)) {
+      if (num_ignore_frames == 0) {
+        // GetFunctionName is an expensive call, only do it if we are
+        // keeping the frame.
+        frame->func_name = GetFunctionName(frame->pc, &frame->func_offset);
+        if (num_frames > 0) {
+          // Set the stack size for the previous frame.
+          backtrace_frame_data_t* prev = &frames_.at(num_frames-1);
+          prev->stack_size = frame->sp - prev->sp;
+        }
+        num_frames++;
+      } else {
+        num_ignore_frames--;
       }
-
-      frame->func_name = GetFunctionName(frame->pc, &frame->func_offset);
-      FillInMap(frame->pc, &frame->map);
-      num_frames++;
-    } else {
-      num_ignore_frames--;
     }
     ret = unw_step (cursor.get());
   } while (ret > 0 && num_frames < MAX_BACKTRACE_FRAMES);
diff --git a/libbacktrace/backtrace_test.cpp b/libbacktrace/backtrace_test.cpp
index d40885647..5de80b1ac 100644
--- a/libbacktrace/backtrace_test.cpp
+++ b/libbacktrace/backtrace_test.cpp
@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+#define _GNU_SOURCE 1
 #include <dirent.h>
 #include <errno.h>
 #include <inttypes.h>
@@ -200,6 +201,23 @@ bool WaitForNonZero(int32_t* value, uint64_t seconds) {
   return false;
 }
 
+TEST(libbacktrace, local_no_unwind_frames) {
+  // Verify that a local unwind does not include any frames within
+  // libunwind or libbacktrace.
+  std::unique_ptr<Backtrace> backtrace(Backtrace::Create(getpid(), getpid()));
+  ASSERT_TRUE(backtrace->Unwind(0));
+
+  ASSERT_TRUE(backtrace->NumFrames() != 0);
+  for (const auto& frame : *backtrace ) {
+    if (BacktraceMap::IsValid(frame.map)) {
+      const std::string name = basename(frame.map.name.c_str());
+      ASSERT_TRUE(name != "libunwind.so" && name != "libbacktrace.so")
+        << DumpFrames(backtrace.get());
+    }
+    break;
+  }
+}
+
 TEST(libbacktrace, local_trace) {
   ASSERT_NE(test_level_one(1, 2, 3, 4, VerifyLevelBacktrace, nullptr), 0);
 }
diff --git a/libcutils/Android.mk b/libcutils/Android.mk
index 9f3230714..0cd560d11 100644
--- a/libcutils/Android.mk
+++ b/libcutils/Android.mk
@@ -22,6 +22,7 @@ commonSources := \
         native_handle.c \
         config_utils.c \
         load_file.c \
+        memory.c \
         open_memstream.c \
         strdup16to8.c \
         strdup8to16.c \
@@ -113,7 +114,6 @@ LOCAL_SRC_FILES := $(commonSources) \
         ashmem-dev.c \
         debugger.c \
         klog.c \
-        memory.c \
         partition_utils.c \
         properties.c \
         qtaguid.c \
diff --git a/libcutils/tests/Android.mk b/libcutils/tests/Android.mk
index 5a5469868..d532dfbf5 100644
--- a/libcutils/tests/Android.mk
+++ b/libcutils/tests/Android.mk
@@ -32,21 +32,19 @@ LOCAL_MODULE_STEM_32 := $(LOCAL_MODULE)32
 LOCAL_MODULE_STEM_64 := $(LOCAL_MODULE)64
 include $(BUILD_NATIVE_TEST)
 
-# The static libcutils tests cannot be built when using libc++ because there are
-# multiple symbol definition errors between libc++ and libgcc. b/18389856
-#include $(CLEAR_VARS)
-#LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk
-#LOCAL_MODULE := libcutils_test_static
-#LOCAL_FORCE_STATIC_EXECUTABLE := true
-#LOCAL_SRC_FILES := $(test_src_files)
-#LOCAL_STATIC_LIBRARIES := \
-#    libc \
-#    libcutils \
-#    liblog \
-#    libutils \
+include $(CLEAR_VARS)
+LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk
+LOCAL_MODULE := libcutils_test_static
+LOCAL_FORCE_STATIC_EXECUTABLE := true
+LOCAL_SRC_FILES := $(test_src_files)
+LOCAL_STATIC_LIBRARIES := \
+    libc \
+    libcutils \
+    liblog \
+    libutils \
 
-#LOCAL_CXX_STL := stlport_static
-#LOCAL_MULTILIB := both
-#LOCAL_MODULE_STEM_32 := $(LOCAL_MODULE)32
-#LOCAL_MODULE_STEM_64 := $(LOCAL_MODULE)64
-#include $(BUILD_NATIVE_TEST)
+LOCAL_CXX_STL := libc++_static
+LOCAL_MULTILIB := both
+LOCAL_MODULE_STEM_32 := $(LOCAL_MODULE)32
+LOCAL_MODULE_STEM_64 := $(LOCAL_MODULE)64
+include $(BUILD_NATIVE_TEST)
diff --git a/sdcard/sdcard.c b/sdcard/sdcard.c
index 4d50bf0d6..39ce0eb3e 100644
--- a/sdcard/sdcard.c
+++ b/sdcard/sdcard.c
@@ -1869,7 +1869,8 @@ static int run(const char* source_path, const char* dest_path, uid_t uid,
             "fd=%i,rootmode=40000,default_permissions,allow_other,user_id=%d,group_id=%d",
             fd, uid, gid);
 
-    res = mount("/dev/fuse", dest_path, "fuse", MS_NOSUID | MS_NODEV | MS_NOEXEC, opts);
+    res = mount("/dev/fuse", dest_path, "fuse", MS_NOSUID | MS_NODEV | MS_NOEXEC |
+            MS_NOATIME, opts);
     if (res < 0) {
         ERROR("cannot mount fuse filesystem: %s\n", strerror(errno));
         goto error;