platform_system_core/libunwindstack/unwind_info.cpp
Christopher Ferris 3958f8060a Elf interface for new unwinder.
This cl includes the code to read arm unwind information from a shared
library.

Bug: 23762183

Test: Passes all unit tests. I can dump the arm unwind information
Test: for an arm shared library.
Change-Id: I43501ea2eab843b81de8bd5128401dd1971af8d3
2017-03-09 12:27:16 -08:00

121 lines
3.3 KiB
C++

/*
* Copyright (C) 2016 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 <elf.h>
#include <errno.h>
#include <fcntl.h>
#include <inttypes.h>
#include <stdio.h>
#include <string.h>
#include <sys/mman.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include "ArmExidx.h"
#include "Elf.h"
#include "ElfInterface.h"
#include "ElfInterfaceArm.h"
#include "Log.h"
void DumpArm(ElfInterfaceArm* interface) {
if (interface == nullptr) {
printf("No ARM Unwind Information.\n\n");
return;
}
printf("ARM Unwind Information:\n");
for (const auto& entry : interface->pt_loads()) {
uint64_t load_bias = entry.second.table_offset;
printf(" PC Range 0x%" PRIx64 " - 0x%" PRIx64 "\n", entry.second.offset + load_bias,
entry.second.table_size + load_bias);
for (auto addr : *interface) {
std::string name;
printf(" PC 0x%" PRIx64, addr + load_bias);
uint64_t func_offset;
if (interface->GetFunctionName(addr + load_bias + 1, &name, &func_offset) && !name.empty()) {
printf(" <%s>", name.c_str());
}
printf("\n");
uint64_t entry;
if (!interface->FindEntry(addr + load_bias, &entry)) {
printf(" Cannot find entry for address.\n");
continue;
}
ArmExidx arm(nullptr, interface->memory(), nullptr);
arm.set_log(true);
arm.set_log_skip_execution(true);
arm.set_log_indent(2);
if (!arm.ExtractEntryData(entry)) {
if (arm.status() != ARM_STATUS_NO_UNWIND) {
printf(" Error trying to extract data.\n");
}
continue;
}
if (arm.data()->size() > 0) {
if (!arm.Eval() && arm.status() != ARM_STATUS_NO_UNWIND) {
printf(" Error trying to evaluate dwarf data.\n");
}
}
}
}
printf("\n");
}
int main(int argc, char** argv) {
if (argc != 2) {
printf("Need to pass the name of an elf file to the program.\n");
return 1;
}
struct stat st;
if (stat(argv[1], &st) == -1) {
printf("Cannot stat %s: %s\n", argv[1], strerror(errno));
return 1;
}
if (!S_ISREG(st.st_mode)) {
printf("%s is not a regular file.\n", argv[1]);
return 1;
}
if (S_ISDIR(st.st_mode)) {
printf("%s is a directory.\n", argv[1]);
return 1;
}
// Send all log messages to stdout.
log_to_stdout(true);
MemoryFileAtOffset* memory = new MemoryFileAtOffset;
if (!memory->Init(argv[1], 0)) {
// Initializatation failed.
printf("Failed to init\n");
return 1;
}
Elf elf(memory);
if (!elf.Init() || !elf.valid()) {
printf("%s is not a valid elf file.\n", argv[1]);
return 1;
}
ElfInterface* interface = elf.interface();
if (elf.machine_type() == EM_ARM) {
DumpArm(reinterpret_cast<ElfInterfaceArm*>(interface));
printf("\n");
}
return 0;
}