Refactor the code.
The object hierarchy was confusing and convoluted. This removes
a lot of unnecessary code, and consolidates the BacktraceCurrent
and BacktraceThread code into BacktraceCurrent.
Change-Id: I01c8407d493712a48169df49dd3ff46db4a7c3ae
diff --git a/libbacktrace/Backtrace.cpp b/libbacktrace/Backtrace.cpp
new file mode 100644
index 0000000..91ca8b7
--- /dev/null
+++ b/libbacktrace/Backtrace.cpp
@@ -0,0 +1,138 @@
+/*
+ * Copyright (C) 2013 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <inttypes.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <sys/types.h>
+#include <ucontext.h>
+
+#include <string>
+
+#include <base/stringprintf.h>
+
+#include <backtrace/Backtrace.h>
+#include <backtrace/BacktraceMap.h>
+
+#include "BacktraceLog.h"
+#include "thread_utils.h"
+#include "UnwindCurrent.h"
+#include "UnwindPtrace.h"
+
+using android::base::StringPrintf;
+
+//-------------------------------------------------------------------------
+// Backtrace functions.
+//-------------------------------------------------------------------------
+Backtrace::Backtrace(pid_t pid, pid_t tid, BacktraceMap* map)
+ : pid_(pid), tid_(tid), map_(map), map_shared_(true) {
+ if (map_ == nullptr) {
+ map_ = BacktraceMap::Create(pid);
+ map_shared_ = false;
+ }
+}
+
+Backtrace::~Backtrace() {
+ if (map_ && !map_shared_) {
+ delete map_;
+ map_ = nullptr;
+ }
+}
+
+extern "C" char* __cxa_demangle(const char* mangled, char* buf, size_t* len,
+ int* status);
+
+std::string Backtrace::GetFunctionName(uintptr_t pc, uintptr_t* offset) {
+ std::string func_name = GetFunctionNameRaw(pc, offset);
+ if (!func_name.empty()) {
+#if defined(__APPLE__)
+ // Mac OS' __cxa_demangle demangles "f" as "float"; last tested on 10.7.
+ if (func_name[0] != '_') {
+ return func_name;
+ }
+#endif
+ char* name = __cxa_demangle(func_name.c_str(), 0, 0, 0);
+ if (name) {
+ func_name = name;
+ free(name);
+ }
+ }
+ return func_name;
+}
+
+bool Backtrace::VerifyReadWordArgs(uintptr_t ptr, word_t* out_value) {
+ if (ptr & (sizeof(word_t)-1)) {
+ BACK_LOGW("invalid pointer %p", reinterpret_cast<void*>(ptr));
+ *out_value = static_cast<word_t>(-1);
+ return false;
+ }
+ return true;
+}
+
+std::string Backtrace::FormatFrameData(size_t frame_num) {
+ if (frame_num >= frames_.size()) {
+ return "";
+ }
+ return FormatFrameData(&frames_[frame_num]);
+}
+
+std::string Backtrace::FormatFrameData(const backtrace_frame_data_t* frame) {
+ const char* map_name;
+ if (BacktraceMap::IsValid(frame->map) && !frame->map.name.empty()) {
+ map_name = frame->map.name.c_str();
+ } else {
+ map_name = "<unknown>";
+ }
+
+ uintptr_t relative_pc;
+ if (BacktraceMap::IsValid(frame->map)) {
+ relative_pc = frame->pc - frame->map.start;
+ } else {
+ relative_pc = frame->pc;
+ }
+
+ std::string line(StringPrintf("#%02zu pc %" PRIPTR " %s", frame->num, relative_pc, map_name));
+ if (!frame->func_name.empty()) {
+ line += " (" + frame->func_name;
+ if (frame->func_offset) {
+ line += StringPrintf("+%" PRIuPTR, frame->func_offset);
+ }
+ line += ')';
+ }
+
+ return line;
+}
+
+void Backtrace::FillInMap(uintptr_t pc, backtrace_map_t* map) {
+ map_->FillIn(pc, map);
+}
+
+Backtrace* Backtrace::Create(pid_t pid, pid_t tid, BacktraceMap* map) {
+ if (pid == BACKTRACE_CURRENT_PROCESS) {
+ pid = getpid();
+ if (tid == BACKTRACE_CURRENT_THREAD) {
+ tid = gettid();
+ }
+ } else if (tid == BACKTRACE_CURRENT_THREAD) {
+ tid = pid;
+ }
+
+ if (pid == getpid()) {
+ return new UnwindCurrent(pid, tid, map);
+ } else {
+ return new UnwindPtrace(pid, tid, map);
+ }
+}