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/*
* 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 <inttypes.h>
#include <signal.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ptrace.h>
#include <sys/types.h>
#include <unistd.h>
#include <string>
#include <unwindstack/Elf.h>
#include <unwindstack/MapInfo.h>
#include <unwindstack/Maps.h>
#include <unwindstack/Memory.h>
#include <unwindstack/Regs.h>
static bool Attach(pid_t pid) {
if (ptrace(PTRACE_ATTACH, pid, 0, 0) == -1) {
return false;
}
// Allow at least 1 second to attach properly.
for (size_t i = 0; i < 1000; i++) {
siginfo_t si;
if (ptrace(PTRACE_GETSIGINFO, pid, 0, &si) == 0) {
return true;
}
usleep(1000);
}
printf("%d: Failed to stop.\n", pid);
return false;
}
static bool Detach(pid_t pid) {
return ptrace(PTRACE_DETACH, pid, 0, 0) == 0;
}
void DoUnwind(pid_t pid) {
unwindstack::RemoteMaps remote_maps(pid);
if (!remote_maps.Parse()) {
printf("Failed to parse map data.\n");
return;
}
uint32_t machine_type;
unwindstack::Regs* regs = unwindstack::Regs::RemoteGet(pid, &machine_type);
if (regs == nullptr) {
printf("Unable to get remote reg data\n");
return;
}
bool bits32 = true;
printf("ABI: ");
switch (machine_type) {
case EM_ARM:
printf("arm");
break;
case EM_386:
printf("x86");
break;
case EM_AARCH64:
printf("arm64");
bits32 = false;
break;
case EM_X86_64:
printf("x86_64");
bits32 = false;
break;
default:
printf("unknown\n");
return;
}
printf("\n");
unwindstack::MemoryRemote remote_memory(pid);
for (size_t frame_num = 0; frame_num < 64; frame_num++) {
if (regs->pc() == 0) {
break;
}
unwindstack::MapInfo* map_info = remote_maps.Find(regs->pc());
if (map_info == nullptr) {
printf("Failed to find map data for the pc\n");
break;
}
unwindstack::Elf* elf = map_info->GetElf(pid, true);
uint64_t rel_pc = elf->GetRelPc(regs->pc(), map_info);
uint64_t adjusted_rel_pc = rel_pc;
// Don't need to adjust the first frame pc.
if (frame_num != 0) {
adjusted_rel_pc = regs->GetAdjustedPc(rel_pc, elf);
}
std::string name;
if (bits32) {
printf(" #%02zu pc %08" PRIx64, frame_num, adjusted_rel_pc);
} else {
printf(" #%02zu pc %016" PRIx64, frame_num, adjusted_rel_pc);
}
if (!map_info->name.empty()) {
printf(" %s", map_info->name.c_str());
if (map_info->elf_offset != 0) {
printf(" (offset 0x%" PRIx64 ")", map_info->elf_offset);
}
} else {
printf(" <anonymous:%" PRIx64 ">", map_info->offset);
}
uint64_t func_offset;
if (elf->GetFunctionName(adjusted_rel_pc, &name, &func_offset)) {
printf(" (%s", name.c_str());
if (func_offset != 0) {
printf("+%" PRId64, func_offset);
}
printf(")");
}
printf("\n");
if (!elf->Step(rel_pc + map_info->elf_offset, regs, &remote_memory)) {
break;
}
}
}
int main(int argc, char** argv) {
if (argc != 2) {
printf("Usage: unwind <PID>\n");
return 1;
}
pid_t pid = atoi(argv[1]);
if (!Attach(pid)) {
printf("Failed to attach to pid %d: %s\n", pid, strerror(errno));
return 1;
}
DoUnwind(pid);
Detach(pid);
return 0;
}
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