Rewrite libbacktrace to be all C++.
This includes removing the map_info.c source and replacing it with the
BacktraceMap class to handle all map related code.
Change all callers of libbacktrace map functionality.
Also modify the corkscrew thread code so that it doesn't need to build
the map twice (once in the corkscrew format and once in the libbacktrace
format).
Change-Id: I32865a39f83a3dd6f958fc03c2759ba47d12382e
diff --git a/libbacktrace/Corkscrew.cpp b/libbacktrace/Corkscrew.cpp
index 63b8c7c..fd31a26 100644
--- a/libbacktrace/Corkscrew.cpp
+++ b/libbacktrace/Corkscrew.cpp
@@ -16,12 +16,11 @@
#define LOG_TAG "libbacktrace"
-#include <backtrace/backtrace.h>
+#include <backtrace/Backtrace.h>
#include <string.h>
#include <backtrace-arch.h>
-#include <cutils/log.h>
#include <corkscrew/backtrace.h>
#ifndef __USE_GNU
@@ -32,6 +31,48 @@
#include "Corkscrew.h"
//-------------------------------------------------------------------------
+// CorkscrewMap functions.
+//-------------------------------------------------------------------------
+CorkscrewMap::CorkscrewMap(pid_t pid) : BacktraceMap(pid), map_info_(NULL) {
+}
+
+CorkscrewMap::~CorkscrewMap() {
+ if (map_info_) {
+ free_map_info_list(map_info_);
+ map_info_ = NULL;
+ }
+}
+
+bool CorkscrewMap::Build() {
+ map_info_ = load_map_info_list(pid_);
+
+ // Use the information in map_info_ to construct the BacktraceMap data
+ // rather than reparsing /proc/self/maps.
+ map_info_t* cur_map = map_info_;
+ while (cur_map) {
+ backtrace_map_t map;
+ map.start = cur_map->start;
+ map.end = cur_map->end;
+ map.flags = 0;
+ if (cur_map->is_readable) {
+ map.flags |= PROT_READ;
+ }
+ if (cur_map->is_writable) {
+ map.flags |= PROT_WRITE;
+ }
+ if (cur_map->is_executable) {
+ map.flags |= PROT_EXEC;
+ }
+ map.name = cur_map->name;
+
+ maps_.push_back(map);
+
+ cur_map = cur_map->next;
+ }
+ return map_info_ != NULL;
+}
+
+//-------------------------------------------------------------------------
// CorkscrewCommon functions.
//-------------------------------------------------------------------------
bool CorkscrewCommon::GenerateFrameData(
@@ -41,29 +82,19 @@
return false;
}
- backtrace_t* data = GetBacktraceData();
- data->num_frames = num_frames;
- for (size_t i = 0; i < data->num_frames; i++) {
- backtrace_frame_data_t* frame = &data->frames[i];
- frame->num = i;
- frame->pc = cork_frames[i].absolute_pc;
- frame->sp = cork_frames[i].stack_top;
- frame->stack_size = cork_frames[i].stack_size;
- frame->map_name = NULL;
- frame->map_offset = 0;
- frame->func_name = NULL;
- frame->func_offset = 0;
+ std::vector<backtrace_frame_data_t>* frames = GetFrames();
+ frames->resize(num_frames);
+ size_t i = 0;
+ for (std::vector<backtrace_frame_data_t>::iterator it = frames->begin();
+ it != frames->end(); ++it, ++i) {
+ it->num = i;
+ it->pc = cork_frames[i].absolute_pc;
+ it->sp = cork_frames[i].stack_top;
+ it->stack_size = cork_frames[i].stack_size;
+ it->func_offset = 0;
- uintptr_t map_start;
- frame->map_name = backtrace_obj_->GetMapName(frame->pc, &map_start);
- if (frame->map_name) {
- frame->map_offset = frame->pc - map_start;
- }
-
- std::string func_name = backtrace_obj_->GetFunctionName(frame->pc, &frame->func_offset);
- if (!func_name.empty()) {
- frame->func_name = strdup(func_name.c_str());
- }
+ it->map = backtrace_obj_->FindMap(it->pc);
+ it->func_name = backtrace_obj_->GetFunctionName(it->pc, &it->func_offset);
}
return true;
}
@@ -88,23 +119,23 @@
*offset = 0;
Dl_info info;
- const backtrace_map_info_t* map_info = backtrace_obj_->FindMapInfo(pc);
- if (map_info) {
+ const backtrace_map_t* map = backtrace_obj_->FindMap(pc);
+ if (map) {
if (dladdr((const void*)pc, &info)) {
if (info.dli_sname) {
- *offset = pc - map_info->start - (uintptr_t)info.dli_saddr + (uintptr_t)info.dli_fbase;
+ *offset = pc - map->start - (uintptr_t)info.dli_saddr + (uintptr_t)info.dli_fbase;
return info.dli_sname;
}
} else {
// dladdr(3) didn't find a symbol; maybe it's static? Look in the ELF file...
- symbol_table_t* symbol_table = load_symbol_table(map_info->name);
+ symbol_table_t* symbol_table = load_symbol_table(map->name.c_str());
if (symbol_table) {
// First check if we can find the symbol using a relative pc.
std::string name;
- const symbol_t* elf_symbol = find_symbol(symbol_table, pc - map_info->start);
+ const symbol_t* elf_symbol = find_symbol(symbol_table, pc - map->start);
if (elf_symbol) {
name = elf_symbol->name;
- *offset = pc - map_info->start - elf_symbol->start;
+ *offset = pc - map->start - elf_symbol->start;
} else if ((elf_symbol = find_symbol(symbol_table, pc)) != NULL) {
// Found the symbol using the absolute pc.
name = elf_symbol->name;
@@ -125,39 +156,36 @@
}
CorkscrewThread::~CorkscrewThread() {
- if (corkscrew_map_info_) {
- free_map_info_list(corkscrew_map_info_);
- corkscrew_map_info_ = NULL;
- }
}
bool CorkscrewThread::Init() {
- corkscrew_map_info_ = load_map_info_list(backtrace_obj_->Pid());
- return corkscrew_map_info_ != NULL;
+ if (backtrace_obj_->GetMap() == NULL) {
+ // Trigger the map object creation, which will create the corkscrew
+ // map information.
+ return BuildMap();
+ }
+ return true;
}
void CorkscrewThread::ThreadUnwind(
siginfo_t* siginfo, void* sigcontext, size_t num_ignore_frames) {
- backtrace_frame_t frames[MAX_BACKTRACE_FRAMES];
+ backtrace_frame_t cork_frames[MAX_BACKTRACE_FRAMES];
+ CorkscrewMap* map = static_cast<CorkscrewMap*>(backtrace_obj_->GetMap());
ssize_t num_frames = unwind_backtrace_signal_arch(
- siginfo, sigcontext, corkscrew_map_info_, frames, num_ignore_frames,
- MAX_BACKTRACE_FRAMES);
+ siginfo, sigcontext, map->GetMapInfo(), cork_frames,
+ num_ignore_frames, MAX_BACKTRACE_FRAMES);
if (num_frames > 0) {
- backtrace_t* data = GetBacktraceData();
- data->num_frames = num_frames;
- for (size_t i = 0; i < data->num_frames; i++) {
- backtrace_frame_data_t* frame = &data->frames[i];
- frame->num = i;
- frame->pc = frames[i].absolute_pc;
- frame->sp = frames[i].stack_top;
- frame->stack_size = frames[i].stack_size;
-
- frame->map_offset = 0;
- frame->map_name = NULL;
- frame->map_offset = 0;
-
- frame->func_offset = 0;
- frame->func_name = NULL;
+ std::vector<backtrace_frame_data_t>* frames = GetFrames();
+ frames->resize(num_frames);
+ size_t i = 0;
+ for (std::vector<backtrace_frame_data_t>::iterator it = frames->begin();
+ it != frames->end(); ++it, ++i) {
+ it->num = i;
+ it->pc = cork_frames[i].absolute_pc;
+ it->sp = cork_frames[i].stack_top;
+ it->stack_size = cork_frames[i].stack_size;
+ it->map = NULL;
+ it->func_offset = 0;
}
}
}
@@ -206,15 +234,15 @@
//-------------------------------------------------------------------------
// C++ object creation functions.
//-------------------------------------------------------------------------
-Backtrace* CreateCurrentObj(backtrace_map_info_t* map_info) {
- return new BacktraceCurrent(new CorkscrewCurrent(), map_info);
+Backtrace* CreateCurrentObj(BacktraceMap* map) {
+ return new BacktraceCurrent(new CorkscrewCurrent(), map);
}
-Backtrace* CreatePtraceObj(pid_t pid, pid_t tid, backtrace_map_info_t* map_info) {
- return new BacktracePtrace(new CorkscrewPtrace(), pid, tid, map_info);
+Backtrace* CreatePtraceObj(pid_t pid, pid_t tid, BacktraceMap* map) {
+ return new BacktracePtrace(new CorkscrewPtrace(), pid, tid, map);
}
-Backtrace* CreateThreadObj(pid_t tid, backtrace_map_info_t* map_info) {
+Backtrace* CreateThreadObj(pid_t tid, BacktraceMap* map) {
CorkscrewThread* thread_obj = new CorkscrewThread();
- return new BacktraceThread(thread_obj, thread_obj, tid, map_info);
+ return new BacktraceThread(thread_obj, thread_obj, tid, map);
}