Move tools to separate directory.

Bug: 23762183

Test: Ran unit tests, ran new tools.
Change-Id: Icc7cbb4102a68042f4683d6dd622f21bc5e74deb
diff --git a/libunwindstack/tools/unwind.cpp b/libunwindstack/tools/unwind.cpp
new file mode 100644
index 0000000..34cd1ce
--- /dev/null
+++ b/libunwindstack/tools/unwind.cpp
@@ -0,0 +1,160 @@
+/*
+ * 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 <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 "Elf.h"
+#include "Maps.h"
+#include "Memory.h"
+#include "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) {
+  RemoteMaps remote_maps(pid);
+  if (!remote_maps.Parse()) {
+    printf("Failed to parse map data.\n");
+    return;
+  }
+
+  uint32_t machine_type;
+  Regs* regs = 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");
+
+  MemoryRemote remote_memory(pid);
+  for (size_t frame_num = 0; frame_num < 64; frame_num++) {
+    if (regs->pc() == 0) {
+      break;
+    }
+    MapInfo* map_info = remote_maps.Find(regs->pc());
+    if (map_info == nullptr) {
+      printf("Failed to find map data for the pc\n");
+      break;
+    }
+
+    Elf* elf = map_info->GetElf(pid, true);
+
+    uint64_t rel_pc = regs->GetRelPc(elf, 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;
+}