Rewrite libbacktrace using C++.
The old code was essentially trying to be C++ in C and was awkward. This
change makes it all objects with a thin layer that C code can use.
There is a C++ backtrace object that is not very useful, this code will
replace it.
This change also includes moving the backtrace test to a gtest, and adding
coverage of all major functionality.
Bug: 8410085
Change-Id: Iae0f1b09b3dd60395f71ed66010c1ea5cdd37841
diff --git a/include/backtrace/Backtrace.h b/include/backtrace/Backtrace.h
new file mode 100644
index 0000000..0b75e83
--- /dev/null
+++ b/include/backtrace/Backtrace.h
@@ -0,0 +1,85 @@
+/*
+ * 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.
+ */
+
+#ifndef _BACKTRACE_BACKTRACE_H
+#define _BACKTRACE_BACKTRACE_H
+
+#include <backtrace/backtrace.h>
+
+#include <string>
+
+class BacktraceImpl;
+
+class Backtrace {
+public:
+ Backtrace(BacktraceImpl* impl);
+ virtual ~Backtrace();
+
+ // Get the current stack trace and store in the backtrace_ structure.
+ virtual bool Unwind(size_t num_ignore_frames);
+
+ // Get the function name and offset into the function given the pc.
+ // If the string is empty, then no valid function name was found.
+ virtual std::string GetFunctionName(uintptr_t pc, uintptr_t* offset);
+
+ // Get the name of the map associated with the given pc. If NULL is returned,
+ // then map_start is not set. Otherwise, map_start is the beginning of this
+ // map.
+ virtual const char* GetMapName(uintptr_t pc, uintptr_t* map_start);
+
+ // Finds the memory map associated with the given ptr.
+ virtual const backtrace_map_info_t* FindMapInfo(uintptr_t ptr);
+
+ // Read the data at a specific address.
+ virtual bool ReadWord(uintptr_t ptr, uint32_t* out_value) = 0;
+
+ // Create a string representing the formatted line of backtrace information
+ // for a single frame.
+ virtual std::string FormatFrameData(size_t frame_num);
+
+ pid_t Pid() { return backtrace_.pid; }
+ pid_t Tid() { return backtrace_.tid; }
+ size_t NumFrames() { return backtrace_.num_frames; }
+
+ const backtrace_t* GetBacktrace() { return &backtrace_; }
+
+ const backtrace_frame_data_t* GetFrame(size_t frame_num) {
+ return &backtrace_.frames[frame_num];
+ }
+
+ // Create the correct Backtrace object based on what is to be unwound.
+ // If pid < 0 or equals the current pid, then the Backtrace object
+ // corresponds to the current process.
+ // If pid < 0 or equals the current pid and tid >= 0, then the Backtrace
+ // object corresponds to a thread in the current process.
+ // If pid >= 0 and tid < 0, then the Backtrace object corresponds to a
+ // different process.
+ // Tracing a thread in a different process is not supported.
+ static Backtrace* Create(pid_t pid, pid_t tid);
+
+protected:
+ virtual bool VerifyReadWordArgs(uintptr_t ptr, uint32_t* out_value);
+
+ BacktraceImpl* impl_;
+
+ backtrace_map_info_t* map_info_;
+
+ backtrace_t backtrace_;
+
+ friend class BacktraceImpl;
+};
+
+#endif // _BACKTRACE_BACKTRACE_H