Merge "split LightRefBase out of RefBase" into oc-dev
am: ed6aad1cbb

Change-Id: Ie976eb317714023fd56bced28fb605691ce4a7b3
diff --git a/.clang-format-2 b/.clang-format-2
index aab4665..41591ce 100644
--- a/.clang-format-2
+++ b/.clang-format-2
@@ -1,4 +1,5 @@
 BasedOnStyle: Google
+AllowShortFunctionsOnASingleLine: Inline
 ColumnLimit: 100
 CommentPragmas: NOLINT:.*
 DerivePointerAlignment: false
diff --git a/.clang-format-4 b/.clang-format-4
index 1497447..ae4a451 100644
--- a/.clang-format-4
+++ b/.clang-format-4
@@ -1,5 +1,6 @@
 BasedOnStyle: Google
 AccessModifierOffset: -2
+AllowShortFunctionsOnASingleLine: Inline
 ColumnLimit: 100
 CommentPragmas: NOLINT:.*
 DerivePointerAlignment: false
diff --git a/base/include/android-base/properties.h b/base/include/android-base/properties.h
index 4de5e57..041586c 100644
--- a/base/include/android-base/properties.h
+++ b/base/include/android-base/properties.h
@@ -62,15 +62,14 @@
 // Waits for the system property `key` to have the value `expected_value`.
 // Times out after `relative_timeout`.
 // Returns true on success, false on timeout.
-bool WaitForProperty(const std::string& key,
-                     const std::string& expected_value,
-                     std::chrono::milliseconds relative_timeout);
+bool WaitForProperty(const std::string& key, const std::string& expected_value,
+                     std::chrono::milliseconds relative_timeout = std::chrono::milliseconds::max());
 
 // Waits for the system property `key` to be created.
 // Times out after `relative_timeout`.
 // Returns true on success, false on timeout.
-bool WaitForPropertyCreation(const std::string& key,
-                             std::chrono::milliseconds relative_timeout);
+bool WaitForPropertyCreation(const std::string& key, std::chrono::milliseconds relative_timeout =
+                                                         std::chrono::milliseconds::max());
 
 } // namespace base
 } // namespace android
diff --git a/base/properties.cpp b/base/properties.cpp
index 32c0128..816bca0 100644
--- a/base/properties.cpp
+++ b/base/properties.cpp
@@ -101,22 +101,24 @@
 }
 
 // TODO: chrono_utils?
-static void DurationToTimeSpec(timespec& ts, std::chrono::nanoseconds d) {
+static void DurationToTimeSpec(timespec& ts, const std::chrono::milliseconds d) {
   auto s = std::chrono::duration_cast<std::chrono::seconds>(d);
   auto ns = std::chrono::duration_cast<std::chrono::nanoseconds>(d - s);
   ts.tv_sec = s.count();
   ts.tv_nsec = ns.count();
 }
 
+// TODO: boot_clock?
 using AbsTime = std::chrono::time_point<std::chrono::steady_clock>;
 
-static void UpdateTimeSpec(timespec& ts,
-                           const AbsTime& timeout) {
+static void UpdateTimeSpec(timespec& ts, std::chrono::milliseconds relative_timeout,
+                           const AbsTime& start_time) {
   auto now = std::chrono::steady_clock::now();
-  auto remaining_timeout = std::chrono::duration_cast<std::chrono::nanoseconds>(timeout - now);
-  if (remaining_timeout < 0ns) {
+  auto time_elapsed = std::chrono::duration_cast<std::chrono::milliseconds>(now - start_time);
+  if (time_elapsed >= relative_timeout) {
     ts = { 0, 0 };
   } else {
+    auto remaining_timeout = relative_timeout - time_elapsed;
     DurationToTimeSpec(ts, remaining_timeout);
   }
 }
@@ -127,11 +129,7 @@
 // Returns nullptr on timeout.
 static const prop_info* WaitForPropertyCreation(const std::string& key,
                                                 const std::chrono::milliseconds& relative_timeout,
-                                                AbsTime& absolute_timeout) {
-  // TODO: boot_clock?
-  auto now = std::chrono::steady_clock::now();
-  absolute_timeout = now + relative_timeout;
-
+                                                const AbsTime& start_time) {
   // Find the property's prop_info*.
   const prop_info* pi;
   unsigned global_serial = 0;
@@ -139,17 +137,16 @@
     // The property doesn't even exist yet.
     // Wait for a global change and then look again.
     timespec ts;
-    UpdateTimeSpec(ts, absolute_timeout);
+    UpdateTimeSpec(ts, relative_timeout, start_time);
     if (!__system_property_wait(nullptr, global_serial, &global_serial, &ts)) return nullptr;
   }
   return pi;
 }
 
-bool WaitForProperty(const std::string& key,
-                     const std::string& expected_value,
+bool WaitForProperty(const std::string& key, const std::string& expected_value,
                      std::chrono::milliseconds relative_timeout) {
-  AbsTime absolute_timeout;
-  const prop_info* pi = WaitForPropertyCreation(key, relative_timeout, absolute_timeout);
+  auto start_time = std::chrono::steady_clock::now();
+  const prop_info* pi = WaitForPropertyCreation(key, relative_timeout, start_time);
   if (pi == nullptr) return false;
 
   WaitForPropertyData data;
@@ -162,7 +159,7 @@
     if (data.done) return true;
 
     // It didn't, so wait for the property to change before checking again.
-    UpdateTimeSpec(ts, absolute_timeout);
+    UpdateTimeSpec(ts, relative_timeout, start_time);
     uint32_t unused;
     if (!__system_property_wait(pi, data.last_read_serial, &unused, &ts)) return false;
   }
@@ -170,8 +167,8 @@
 
 bool WaitForPropertyCreation(const std::string& key,
                              std::chrono::milliseconds relative_timeout) {
-  AbsTime absolute_timeout;
-  return (WaitForPropertyCreation(key, relative_timeout, absolute_timeout) != nullptr);
+  auto start_time = std::chrono::steady_clock::now();
+  return (WaitForPropertyCreation(key, relative_timeout, start_time) != nullptr);
 }
 
 }  // namespace base
diff --git a/base/properties_test.cpp b/base/properties_test.cpp
index 1bbe482..de5f3dc 100644
--- a/base/properties_test.cpp
+++ b/base/properties_test.cpp
@@ -151,6 +151,38 @@
   ASSERT_LT(std::chrono::duration_cast<std::chrono::milliseconds>(t1 - t0), 600ms);
 }
 
+TEST(properties, WaitForProperty_MaxTimeout) {
+  std::atomic<bool> flag{false};
+  std::thread thread([&]() {
+    android::base::SetProperty("debug.libbase.WaitForProperty_test", "a");
+    while (!flag) std::this_thread::yield();
+    std::this_thread::sleep_for(500ms);
+    android::base::SetProperty("debug.libbase.WaitForProperty_test", "b");
+  });
+
+  ASSERT_TRUE(android::base::WaitForProperty("debug.libbase.WaitForProperty_test", "a", 1s));
+  flag = true;
+  // Test that this does not immediately return false due to overflow issues with the timeout.
+  ASSERT_TRUE(android::base::WaitForProperty("debug.libbase.WaitForProperty_test", "b"));
+  thread.join();
+}
+
+TEST(properties, WaitForProperty_NegativeTimeout) {
+  std::atomic<bool> flag{false};
+  std::thread thread([&]() {
+    android::base::SetProperty("debug.libbase.WaitForProperty_test", "a");
+    while (!flag) std::this_thread::yield();
+    std::this_thread::sleep_for(500ms);
+    android::base::SetProperty("debug.libbase.WaitForProperty_test", "b");
+  });
+
+  ASSERT_TRUE(android::base::WaitForProperty("debug.libbase.WaitForProperty_test", "a", 1s));
+  flag = true;
+  // Assert that this immediately returns with a negative timeout
+  ASSERT_FALSE(android::base::WaitForProperty("debug.libbase.WaitForProperty_test", "b", -100ms));
+  thread.join();
+}
+
 TEST(properties, WaitForPropertyCreation) {
   std::thread thread([&]() {
     std::this_thread::sleep_for(100ms);
diff --git a/demangle/demangle.cpp b/demangle/demangle.cpp
index be4d2dd..66e5e58 100644
--- a/demangle/demangle.cpp
+++ b/demangle/demangle.cpp
@@ -20,22 +20,25 @@
 #include <string.h>
 #include <unistd.h>
 
+#include <cctype>
 #include <string>
 
 #include <demangle.h>
 
 extern "C" char* __cxa_demangle(const char*, char*, size_t*, int*);
 
-void usage(const char* prog_name) {
-  printf("Usage: %s [-c] <NAME_TO_DEMANGLE>\n", prog_name);
-  printf("  -c\n");
-  printf("    Compare the results of __cxa_demangle against the current\n");
-  printf("    demangler.\n");
+static void Usage(const char* prog_name) {
+  printf("usage: %s [-c] [NAME_TO_DEMANGLE...]\n", prog_name);
+  printf("\n");
+  printf("Demangles C++ mangled names if supplied on the command-line, or found\n");
+  printf("reading from stdin otherwise.\n");
+  printf("\n");
+  printf("-c\tCompare against __cxa_demangle\n");
+  printf("\n");
 }
 
-std::string DemangleWithCxa(const char* name) {
+static std::string DemangleWithCxa(const char* name) {
   const char* cxa_demangle = __cxa_demangle(name, nullptr, nullptr, nullptr);
-
   if (cxa_demangle == nullptr) {
     return name;
   }
@@ -54,6 +57,49 @@
   return demangled_str;
 }
 
+static void Compare(const char* name, const std::string& demangled_name) {
+  std::string cxa_demangled_name(DemangleWithCxa(name));
+  if (cxa_demangled_name != demangled_name) {
+    printf("\nMismatch!\n");
+    printf("\tmangled name: %s\n", name);
+    printf("\tour demangle: %s\n", demangled_name.c_str());
+    printf("\tcxa demangle: %s\n", cxa_demangled_name.c_str());
+    exit(1);
+  }
+}
+
+static int Filter(bool compare) {
+  char* line = nullptr;
+  size_t line_length = 0;
+
+  while ((getline(&line, &line_length, stdin)) != -1) {
+    char* p = line;
+    char* name;
+    while ((name = strstr(p, "_Z")) != nullptr) {
+      // Output anything before the identifier.
+      *name = 0;
+      printf("%s", p);
+      *name = '_';
+
+      // Extract the identifier.
+      p = name;
+      while (*p && (std::isalnum(*p) || *p == '_' || *p == '.' || *p == '$')) ++p;
+
+      // Demangle and output.
+      std::string identifier(name, p);
+      std::string demangled_name = demangle(identifier.c_str());
+      printf("%s", demangled_name.c_str());
+
+      if (compare) Compare(identifier.c_str(), demangled_name);
+    }
+    // Output anything after the last identifier.
+    printf("%s", p);
+  }
+
+  free(line);
+  return 0;
+}
+
 int main(int argc, char** argv) {
 #ifdef __BIONIC__
   const char* prog_name = getprogname();
@@ -67,31 +113,21 @@
     if (opt_char == 'c') {
       compare = true;
     } else {
-      usage(prog_name);
+      Usage(prog_name);
       return 1;
     }
   }
-  if (optind >= argc || argc - optind != 1) {
-    printf("Must supply a single argument.\n\n");
-    usage(prog_name);
-    return 1;
-  }
-  const char* name = argv[optind];
 
-  std::string demangled_name = demangle(name);
+  // With no arguments, act as a filter.
+  if (optind == argc) return Filter(compare);
 
-  printf("%s\n", demangled_name.c_str());
+  // Otherwise demangle each argument.
+  while (optind < argc) {
+    const char* name = argv[optind++];
+    std::string demangled_name = demangle(name);
+    printf("%s\n", demangled_name.c_str());
 
-  if (compare) {
-    std::string cxa_demangle_str(DemangleWithCxa(name));
-
-    if (cxa_demangle_str != demangled_name) {
-      printf("Mismatch\n");
-      printf("cxa demangle: %s\n", cxa_demangle_str.c_str());
-      return 1;
-    } else {
-      printf("Match\n");
-    }
+    if (compare) Compare(name, demangled_name);
   }
   return 0;
 }
diff --git a/fs_mgr/fs_mgr_boot_config.cpp b/fs_mgr/fs_mgr_boot_config.cpp
index 5b2f218..cffa6ce 100644
--- a/fs_mgr/fs_mgr_boot_config.cpp
+++ b/fs_mgr/fs_mgr_boot_config.cpp
@@ -56,7 +56,7 @@
             return true;
         }
 
-        LERROR << "Error finding '" << key << "' in device tree";
+        LINFO << "Error finding '" << key << "' in device tree";
     }
 
     return false;
diff --git a/init/Android.mk b/init/Android.mk
index b52c949..1ca88d7 100644
--- a/init/Android.mk
+++ b/init/Android.mk
@@ -16,6 +16,14 @@
     -DREBOOT_BOOTLOADER_ON_PANIC=0
 endif
 
+ifneq (,$(filter eng,$(TARGET_BUILD_VARIANT)))
+init_options += \
+    -DSHUTDOWN_ZERO_TIMEOUT=1
+else
+init_options += \
+    -DSHUTDOWN_ZERO_TIMEOUT=0
+endif
+
 init_options += -DLOG_UEVENTS=0
 
 init_cflags += \
diff --git a/init/README.md b/init/README.md
index 024d559..0d8f495 100644
--- a/init/README.md
+++ b/init/README.md
@@ -311,6 +311,12 @@
   groups can be provided. No other commands will be run until this one
   finishes. _seclabel_ can be a - to denote default. Properties are expanded
   within _argument_.
+  Init halts executing commands until the forked process exits.
+
+`exec_start <service>`
+> Start service a given service and halt processing of additional init commands
+  until it returns.  It functions similarly to the `exec` command, but uses an
+  existing service definition instead of providing them as arguments.
 
 `export <name> <value>`
 > Set the environment variable _name_ equal to _value_ in the
diff --git a/init/action.cpp b/init/action.cpp
index 1bba0f2..2ccf0bc 100644
--- a/init/action.cpp
+++ b/init/action.cpp
@@ -18,14 +18,14 @@
 
 #include <errno.h>
 
-#include <android-base/strings.h>
+#include <android-base/properties.h>
 #include <android-base/stringprintf.h>
+#include <android-base/strings.h>
 
 #include "builtins.h"
 #include "error.h"
 #include "init_parser.h"
 #include "log.h"
-#include "property_service.h"
 #include "util.h"
 
 using android::base::Join;
@@ -219,9 +219,8 @@
                 found = true;
             }
         } else {
-            std::string prop_val = property_get(trigger_name.c_str());
-            if (prop_val.empty() || (trigger_value != "*" &&
-                                     trigger_value != prop_val)) {
+            std::string prop_val = android::base::GetProperty(trigger_name, "");
+            if (prop_val.empty() || (trigger_value != "*" && trigger_value != prop_val)) {
                 return false;
             }
         }
diff --git a/init/bootchart.cpp b/init/bootchart.cpp
index 4a9c32e..beabea1 100644
--- a/init/bootchart.cpp
+++ b/init/bootchart.cpp
@@ -16,8 +16,6 @@
 
 #include "bootchart.h"
 
-#include "property_service.h"
-
 #include <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
@@ -39,6 +37,7 @@
 
 #include <android-base/file.h>
 #include <android-base/logging.h>
+#include <android-base/properties.h>
 #include <android-base/stringprintf.h>
 
 using android::base::StringPrintf;
@@ -72,7 +71,7 @@
   utsname uts;
   if (uname(&uts) == -1) return;
 
-  std::string fingerprint = property_get("ro.build.fingerprint");
+  std::string fingerprint = android::base::GetProperty("ro.build.fingerprint", "");
   if (fingerprint.empty()) return;
 
   std::string kernel_cmdline;
diff --git a/init/builtins.cpp b/init/builtins.cpp
index 95f1aa0..02e314f 100644
--- a/init/builtins.cpp
+++ b/init/builtins.cpp
@@ -45,16 +45,16 @@
 #include <selinux/selinux.h>
 #include <selinux/label.h>
 
-#include <fs_mgr.h>
 #include <android-base/file.h>
 #include <android-base/parseint.h>
-#include <android-base/strings.h>
+#include <android-base/properties.h>
 #include <android-base/stringprintf.h>
+#include <android-base/strings.h>
 #include <bootloader_message/bootloader_message.h>
-#include <cutils/partition_utils.h>
 #include <cutils/android_reboot.h>
 #include <ext4_utils/ext4_crypt.h>
 #include <ext4_utils/ext4_crypt_init_extensions.h>
+#include <fs_mgr.h>
 #include <logwrap/logwrap.h>
 
 #include "action.h"
@@ -167,19 +167,11 @@
 }
 
 static int do_exec(const std::vector<std::string>& args) {
-    Service* svc = ServiceManager::GetInstance().MakeExecOneshotService(args);
-    if (!svc) {
-        return -1;
-    }
-    if (!start_waiting_for_exec()) {
-        return -1;
-    }
-    if (!svc->Start()) {
-        stop_waiting_for_exec();
-        ServiceManager::GetInstance().RemoveService(*svc);
-        return -1;
-    }
-    return 0;
+    return ServiceManager::GetInstance().Exec(args) ? 0 : -1;
+}
+
+static int do_exec_start(const std::vector<std::string>& args) {
+    return ServiceManager::GetInstance().ExecStart(args[1]) ? 0 : -1;
 }
 
 static int do_export(const std::vector<std::string>& args) {
@@ -880,8 +872,7 @@
 }
 
 static bool is_file_crypto() {
-    std::string value = property_get("ro.crypto.type");
-    return value == "file";
+    return android::base::GetProperty("ro.crypto.type", "") == "file";
 }
 
 static int do_installkey(const std::vector<std::string>& args) {
@@ -898,6 +889,7 @@
 
 BuiltinFunctionMap::Map& BuiltinFunctionMap::map() const {
     constexpr std::size_t kMax = std::numeric_limits<std::size_t>::max();
+    // clang-format off
     static const Map builtin_functions = {
         {"bootchart",               {1,     1,    do_bootchart}},
         {"chmod",                   {2,     2,    do_chmod}},
@@ -910,6 +902,7 @@
         {"domainname",              {1,     1,    do_domainname}},
         {"enable",                  {1,     1,    do_enable}},
         {"exec",                    {1,     kMax, do_exec}},
+        {"exec_start",              {1,     1,    do_exec_start}},
         {"export",                  {2,     2,    do_export}},
         {"hostname",                {1,     1,    do_hostname}},
         {"ifup",                    {1,     1,    do_ifup}},
@@ -943,5 +936,6 @@
         {"wait_for_prop",           {2,     2,    do_wait_for_prop}},
         {"write",                   {2,     2,    do_write}},
     };
+    // clang-format on
     return builtin_functions;
 }
diff --git a/init/init.cpp b/init/init.cpp
index 34de279..a1d9f1b 100644
--- a/init/init.cpp
+++ b/init/init.cpp
@@ -41,13 +41,10 @@
 #include <selinux/android.h>
 
 #include <android-base/file.h>
+#include <android-base/properties.h>
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
 #include <android-base/unique_fd.h>
-#include <cutils/fs.h>
-#include <cutils/iosched_policy.h>
-#include <cutils/list.h>
-#include <cutils/sockets.h>
 #include <libavb/libavb.h>
 #include <private/android_filesystem_config.h>
 
@@ -72,6 +69,7 @@
 #include "util.h"
 #include "watchdogd.h"
 
+using android::base::GetProperty;
 using android::base::StringPrintf;
 
 struct selabel_handle *sehandle;
@@ -86,8 +84,6 @@
 
 const char *ENV[32];
 
-static std::unique_ptr<Timer> waiting_for_exec(nullptr);
-
 static int epoll_fd = -1;
 
 static std::unique_ptr<Timer> waiting_for_prop(nullptr);
@@ -135,29 +131,12 @@
     return -1;
 }
 
-bool start_waiting_for_exec()
-{
-    if (waiting_for_exec) {
-        return false;
-    }
-    waiting_for_exec.reset(new Timer());
-    return true;
-}
-
-void stop_waiting_for_exec()
-{
-    if (waiting_for_exec) {
-        LOG(INFO) << "Wait for exec took " << *waiting_for_exec;
-        waiting_for_exec.reset();
-    }
-}
-
 bool start_waiting_for_property(const char *name, const char *value)
 {
     if (waiting_for_prop) {
         return false;
     }
-    if (property_get(name) != value) {
+    if (GetProperty(name, "") != value) {
         // Current property value is not equal to expected value
         wait_prop_name = name;
         wait_prop_value = value;
@@ -445,7 +424,7 @@
 
 static int console_init_action(const std::vector<std::string>& args)
 {
-    std::string console = property_get("ro.boot.console");
+    std::string console = GetProperty("ro.boot.console", "");
     if (!console.empty()) {
         default_console = "/dev/" + console;
     }
@@ -469,11 +448,11 @@
 }
 
 static void export_oem_lock_status() {
-    if (property_get("ro.oem_unlock_supported") != "1") {
+    if (!android::base::GetBoolProperty("ro.oem_unlock_supported", false)) {
         return;
     }
 
-    std::string value = property_get("ro.boot.verifiedbootstate");
+    std::string value = GetProperty("ro.boot.verifiedbootstate", "");
 
     if (!value.empty()) {
         property_set("ro.boot.flash.locked", value == "orange" ? "0" : "1");
@@ -494,7 +473,7 @@
         { "ro.boot.revision",   "ro.revision",   "0", },
     };
     for (size_t i = 0; i < arraysize(prop_map); i++) {
-        std::string value = property_get(prop_map[i].src_prop);
+        std::string value = GetProperty(prop_map[i].src_prop, "");
         property_set(prop_map[i].dst_prop, (!value.empty()) ? value.c_str() : prop_map[i].default_value);
     }
 }
@@ -1284,7 +1263,7 @@
     parser.AddSectionParser("service",std::make_unique<ServiceParser>());
     parser.AddSectionParser("on", std::make_unique<ActionParser>());
     parser.AddSectionParser("import", std::make_unique<ImportParser>());
-    std::string bootscript = property_get("ro.boot.init_rc");
+    std::string bootscript = GetProperty("ro.boot.init_rc", "");
     if (bootscript.empty()) {
         parser.ParseConfig("/init.rc");
         parser.set_is_system_etc_init_loaded(
@@ -1324,7 +1303,7 @@
     am.QueueBuiltinAction(mix_hwrng_into_linux_rng_action, "mix_hwrng_into_linux_rng");
 
     // Don't mount filesystems or start core system services in charger mode.
-    std::string bootmode = property_get("ro.bootmode");
+    std::string bootmode = GetProperty("ro.bootmode", "");
     if (bootmode == "charger") {
         am.QueueEventTrigger("charger");
     } else {
@@ -1338,10 +1317,10 @@
         // By default, sleep until something happens.
         int epoll_timeout_ms = -1;
 
-        if (!(waiting_for_exec || waiting_for_prop)) {
+        if (!(waiting_for_prop || ServiceManager::GetInstance().IsWaitingForExec())) {
             am.ExecuteOneCommand();
         }
-        if (!(waiting_for_exec || waiting_for_prop)) {
+        if (!(waiting_for_prop || ServiceManager::GetInstance().IsWaitingForExec())) {
             restart_processes();
 
             // If there's a process that needs restarting, wake up in time for that.
diff --git a/init/init.h b/init/init.h
index b4d25fb..fe850ef 100644
--- a/init/init.h
+++ b/init/init.h
@@ -32,10 +32,6 @@
 
 int add_environment(const char* key, const char* val);
 
-bool start_waiting_for_exec();
-
-void stop_waiting_for_exec();
-
 bool start_waiting_for_property(const char *name, const char *value);
 
 #endif  /* _INIT_INIT_H */
diff --git a/init/keychords.cpp b/init/keychords.cpp
index 3dbb2f0..5801ea8 100644
--- a/init/keychords.cpp
+++ b/init/keychords.cpp
@@ -23,9 +23,10 @@
 #include <linux/keychord.h>
 #include <unistd.h>
 
+#include <android-base/properties.h>
+
 #include "init.h"
 #include "log.h"
-#include "property_service.h"
 #include "service.h"
 
 static struct input_keychord *keychords = 0;
@@ -74,7 +75,7 @@
     }
 
     // Only handle keychords if adb is enabled.
-    std::string adb_enabled = property_get("init.svc.adbd");
+    std::string adb_enabled = android::base::GetProperty("init.svc.adbd", "");
     if (adb_enabled == "running") {
         Service* svc = ServiceManager::GetInstance().FindServiceByKeychord(id);
         if (svc) {
diff --git a/init/property_service.cpp b/init/property_service.cpp
index 983e684..a4d8b5f 100644
--- a/init/property_service.cpp
+++ b/init/property_service.cpp
@@ -30,10 +30,6 @@
 #include <memory>
 #include <vector>
 
-#include <cutils/misc.h>
-#include <cutils/sockets.h>
-#include <cutils/multiuser.h>
-
 #define _REALLY_INCLUDE_SYS__SYSTEM_PROPERTIES_H_
 #include <sys/_system_properties.h>
 
@@ -118,12 +114,6 @@
     return check_mac_perms(ctl_name, sctx, cr);
 }
 
-std::string property_get(const char* name) {
-    char value[PROP_VALUE_MAX] = {0};
-    __system_property_get(name, value);
-    return value;
-}
-
 static void write_persistent_property(const char *name, const char *value)
 {
     char tempPath[PATH_MAX];
@@ -592,10 +582,7 @@
 
 static void load_override_properties() {
     if (ALLOW_LOCAL_PROP_OVERRIDE) {
-        std::string debuggable = property_get("ro.debuggable");
-        if (debuggable == "1") {
-            load_properties_from_file("/data/local.prop", NULL);
-        }
+        load_properties_from_file("/data/local.prop", NULL);
     }
 }
 
diff --git a/init/property_service.h b/init/property_service.h
index 5d59473..994da63 100644
--- a/init/property_service.h
+++ b/init/property_service.h
@@ -32,7 +32,6 @@
 void load_persist_props(void);
 void load_system_props(void);
 void start_property_service(void);
-std::string property_get(const char* name);
 uint32_t property_set(const std::string& name, const std::string& value);
 bool is_legal_property_name(const std::string& name);
 
diff --git a/init/reboot.cpp b/init/reboot.cpp
index 261a437..e34abdb 100644
--- a/init/reboot.cpp
+++ b/init/reboot.cpp
@@ -32,17 +32,15 @@
 
 #include <android-base/file.h>
 #include <android-base/macros.h>
-#include <android-base/parseint.h>
+#include <android-base/properties.h>
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
 #include <bootloader_message/bootloader_message.h>
 #include <cutils/android_reboot.h>
-#include <cutils/partition_utils.h>
 #include <fs_mgr.h>
 #include <logwrap/logwrap.h>
 
 #include "log.h"
-#include "property_service.h"
 #include "reboot.h"
 #include "service.h"
 #include "util.h"
@@ -342,12 +340,16 @@
         abort();
     }
 
-    std::string timeout = property_get("ro.build.shutdown_timeout");
     /* TODO update default waiting time based on usage data */
-    unsigned int shutdownTimeout = 10;  // default value
-    if (android::base::ParseUint(timeout, &shutdownTimeout)) {
-        LOG(INFO) << "ro.build.shutdown_timeout set:" << shutdownTimeout;
+    constexpr unsigned int shutdownTimeoutDefault = 10;
+    unsigned int shutdownTimeout = shutdownTimeoutDefault;
+    if (SHUTDOWN_ZERO_TIMEOUT) {  // eng build
+        shutdownTimeout = 0;
+    } else {
+        shutdownTimeout =
+            android::base::GetUintProperty("ro.build.shutdown_timeout", shutdownTimeoutDefault);
     }
+    LOG(INFO) << "Shutdown timeout: " << shutdownTimeout;
 
     static const constexpr char* shutdown_critical_services[] = {"vold", "watchdogd"};
     for (const char* name : shutdown_critical_services) {
diff --git a/init/service.cpp b/init/service.cpp
index c6ef838..ede6364 100644
--- a/init/service.cpp
+++ b/init/service.cpp
@@ -34,6 +34,7 @@
 
 #include <android-base/file.h>
 #include <android-base/parseint.h>
+#include <android-base/properties.h>
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
 #include <system/thread_defs.h>
@@ -191,8 +192,8 @@
 }
 
 void Service::NotifyStateChange(const std::string& new_state) const {
-    if ((flags_ & SVC_EXEC) != 0) {
-        // 'exec' commands don't have properties tracking their state.
+    if ((flags_ & SVC_TEMPORARY) != 0) {
+        // Services created by 'exec' are temporary and don't have properties tracking their state.
         return;
     }
 
@@ -259,7 +260,7 @@
     }
 }
 
-bool Service::Reap() {
+void Service::Reap() {
     if (!(flags_ & SVC_ONESHOT) || (flags_ & SVC_RESTART)) {
         KillProcessGroup(SIGKILL);
     }
@@ -270,7 +271,10 @@
 
     if (flags_ & SVC_EXEC) {
         LOG(INFO) << "SVC_EXEC pid " << pid_ << " finished...";
-        return true;
+    }
+
+    if (flags_ & SVC_TEMPORARY) {
+        return;
     }
 
     pid_ = 0;
@@ -285,7 +289,7 @@
     // Disabled and reset processes do not get restarted automatically.
     if (flags_ & (SVC_DISABLED | SVC_RESET))  {
         NotifyStateChange("stopped");
-        return false;
+        return;
     }
 
     // If we crash > 4 times in 4 minutes, reboot into recovery.
@@ -309,7 +313,7 @@
     onrestart_.ExecuteAllCommands();
 
     NotifyStateChange("restarting");
-    return false;
+    return;
 }
 
 void Service::DumpState() const {
@@ -577,6 +581,18 @@
     return (this->*parser)(args, err);
 }
 
+bool Service::ExecStart(std::unique_ptr<Timer>* exec_waiter) {
+    flags_ |= SVC_EXEC | SVC_ONESHOT;
+
+    exec_waiter->reset(new Timer);
+
+    if (!Start()) {
+        exec_waiter->reset();
+        return false;
+    }
+    return true;
+}
+
 bool Service::Start() {
     // Starting a service removes it from the disabled or reset state and
     // immediately takes it out of the restarting state if it was in there.
@@ -657,7 +673,7 @@
         if (iter == writepid_files_.end()) {
             // There were no "writepid" instructions for cpusets, check if the system default
             // cpuset is specified to be used for the process.
-            std::string default_cpuset = property_get("ro.cpuset.default");
+            std::string default_cpuset = android::base::GetProperty("ro.cpuset.default", "");
             if (!default_cpuset.empty()) {
                 // Make sure the cpuset name starts and ends with '/'.
                 // A single '/' means the 'root' cpuset.
@@ -863,6 +879,35 @@
     services_.emplace_back(std::move(service));
 }
 
+bool ServiceManager::Exec(const std::vector<std::string>& args) {
+    Service* svc = MakeExecOneshotService(args);
+    if (!svc) {
+        LOG(ERROR) << "Could not create exec service";
+        return false;
+    }
+    if (!svc->ExecStart(&exec_waiter_)) {
+        LOG(ERROR) << "Could not start exec service";
+        ServiceManager::GetInstance().RemoveService(*svc);
+        return false;
+    }
+    return true;
+}
+
+bool ServiceManager::ExecStart(const std::string& name) {
+    Service* svc = FindServiceByName(name);
+    if (!svc) {
+        LOG(ERROR) << "ExecStart(" << name << "): Service not found";
+        return false;
+    }
+    if (!svc->ExecStart(&exec_waiter_)) {
+        LOG(ERROR) << "ExecStart(" << name << "): Could not start Service";
+        return false;
+    }
+    return true;
+}
+
+bool ServiceManager::IsWaitingForExec() const { return exec_waiter_ != nullptr; }
+
 Service* ServiceManager::MakeExecOneshotService(const std::vector<std::string>& args) {
     // Parse the arguments: exec [SECLABEL [UID [GID]*] --] COMMAND ARGS...
     // SECLABEL can be a - to denote default
@@ -886,7 +931,7 @@
 
     exec_count_++;
     std::string name = StringPrintf("exec %d (%s)", exec_count_, str_args[0].c_str());
-    unsigned flags = SVC_EXEC | SVC_ONESHOT;
+    unsigned flags = SVC_EXEC | SVC_ONESHOT | SVC_TEMPORARY;
     CapSet no_capabilities;
     unsigned namespace_flags = 0;
 
@@ -1026,8 +1071,13 @@
         return true;
     }
 
-    if (svc->Reap()) {
-        stop_waiting_for_exec();
+    svc->Reap();
+
+    if (svc->flags() & SVC_EXEC) {
+        LOG(INFO) << "Wait for exec took " << *exec_waiter_;
+        exec_waiter_.reset();
+    }
+    if (svc->flags() & SVC_TEMPORARY) {
         RemoveService(*svc);
     }
 
diff --git a/init/service.h b/init/service.h
index 9a9046b..f08a03f 100644
--- a/init/service.h
+++ b/init/service.h
@@ -44,10 +44,13 @@
 #define SVC_RC_DISABLED 0x080     // Remember if the disabled flag was set in the rc script.
 #define SVC_RESTART 0x100         // Use to safely restart (stop, wait, start) a service.
 #define SVC_DISABLED_START 0x200  // A start was requested but it was disabled at the time.
-#define SVC_EXEC 0x400            // This synthetic service corresponds to an 'exec'.
+#define SVC_EXEC 0x400  // This service was started by either 'exec' or 'exec_start' and stops
+                        // init from processing more commands until it completes
 
 #define SVC_SHUTDOWN_CRITICAL 0x800  // This service is critical for shutdown and
                                      // should not be killed during shutdown
+#define SVC_TEMPORARY 0x1000  // This service was started by 'exec' and should be removed from the
+                              // service list once it is reaped.
 
 #define NR_SVC_SUPP_GIDS 12    // twelve supplementary groups
 
@@ -72,6 +75,7 @@
 
     bool IsRunning() { return (flags_ & SVC_RUNNING) != 0; }
     bool ParseLine(const std::vector<std::string>& args, std::string* err);
+    bool ExecStart(std::unique_ptr<Timer>* exec_waiter);
     bool Start();
     bool StartIfNotDisabled();
     bool Enable();
@@ -80,7 +84,7 @@
     void Terminate();
     void Restart();
     void RestartIfNeeded(time_t* process_needs_restart_at);
-    bool Reap();
+    void Reap();
     void DumpState() const;
     void SetShutdownCritical() { flags_ |= SVC_SHUTDOWN_CRITICAL; }
     bool IsShutdownCritical() const { return (flags_ & SVC_SHUTDOWN_CRITICAL) != 0; }
@@ -178,6 +182,9 @@
 
     void AddService(std::unique_ptr<Service> service);
     Service* MakeExecOneshotService(const std::vector<std::string>& args);
+    bool Exec(const std::vector<std::string>& args);
+    bool ExecStart(const std::string& name);
+    bool IsWaitingForExec() const;
     Service* FindServiceByName(const std::string& name) const;
     Service* FindServiceByPid(pid_t pid) const;
     Service* FindServiceByKeychord(int keychord_id) const;
@@ -198,6 +205,8 @@
     bool ReapOneProcess();
 
     static int exec_count_; // Every service needs a unique name.
+    std::unique_ptr<Timer> exec_waiter_;
+
     std::vector<std::unique_ptr<Service>> services_;
 };
 
diff --git a/init/signal_handler.cpp b/init/signal_handler.cpp
index 1041b82..5e3acac 100644
--- a/init/signal_handler.cpp
+++ b/init/signal_handler.cpp
@@ -24,8 +24,6 @@
 #include <unistd.h>
 
 #include <android-base/stringprintf.h>
-#include <cutils/list.h>
-#include <cutils/sockets.h>
 
 #include "action.h"
 #include "init.h"
diff --git a/init/ueventd.cpp b/init/ueventd.cpp
index 915afbd..f27be64 100644
--- a/init/ueventd.cpp
+++ b/init/ueventd.cpp
@@ -26,6 +26,7 @@
 
 #include <sys/types.h>
 
+#include <android-base/properties.h>
 #include <android-base/stringprintf.h>
 #include <selinux/selinux.h>
 
@@ -34,7 +35,6 @@
 #include "util.h"
 #include "devices.h"
 #include "ueventd_parser.h"
-#include "property_service.h"
 
 int ueventd_main(int argc, char **argv)
 {
@@ -71,7 +71,7 @@
      * TODO: cleanup platform ueventd.rc to remove vendor specific
      * device node entries (b/34968103)
      */
-    std::string hardware = property_get("ro.hardware");
+    std::string hardware = android::base::GetProperty("ro.hardware", "");
     ueventd_parse_config_file(android::base::StringPrintf("/ueventd.%s.rc", hardware.c_str()).c_str());
 
     device_init();
diff --git a/init/util.cpp b/init/util.cpp
index 0ba9800..8a19939 100644
--- a/init/util.cpp
+++ b/init/util.cpp
@@ -38,6 +38,7 @@
 
 #include <android-base/file.h>
 #include <android-base/logging.h>
+#include <android-base/properties.h>
 #include <android-base/stringprintf.h>
 #include <android-base/strings.h>
 #include <android-base/unique_fd.h>
@@ -48,7 +49,6 @@
 
 #include "init.h"
 #include "log.h"
-#include "property_service.h"
 #include "reboot.h"
 #include "util.h"
 
@@ -395,7 +395,7 @@
             return false;
         }
 
-        std::string prop_val = property_get(prop_name.c_str());
+        std::string prop_val = android::base::GetProperty(prop_name, "");
         if (prop_val.empty()) {
             if (def_val.empty()) {
                 LOG(ERROR) << "property '" << prop_name << "' doesn't exist while expanding '" << src << "'";
diff --git a/libcutils/canned_fs_config.c b/libcutils/canned_fs_config.c
index e0e6a34..96ca566 100644
--- a/libcutils/canned_fs_config.c
+++ b/libcutils/canned_fs_config.c
@@ -17,6 +17,7 @@
 #include <errno.h>
 #include <inttypes.h>
 #include <limits.h>
+#include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -41,7 +42,7 @@
 }
 
 int load_canned_fs_config(const char* fn) {
-    char line[PATH_MAX + 200];
+    char buf[PATH_MAX + 200];
     FILE* f;
 
     f = fopen(fn, "r");
@@ -50,17 +51,21 @@
         return -1;
     }
 
-    while (fgets(line, sizeof(line), f)) {
+    while (fgets(buf, sizeof(buf), f)) {
         Path* p;
         char* token;
+        char* line = buf;
+        bool rootdir;
 
         while (canned_used >= canned_alloc) {
             canned_alloc = (canned_alloc+1) * 2;
             canned_data = (Path*) realloc(canned_data, canned_alloc * sizeof(Path));
         }
         p = canned_data + canned_used;
-        p->path = strdup(strtok(line, " "));
-        p->uid = atoi(strtok(NULL, " "));
+        if (line[0] == '/') line++;
+        rootdir = line[0] == ' ';
+        p->path = strdup(rootdir ? "" : strtok(line, " "));
+        p->uid = atoi(strtok(rootdir ? line : NULL, " "));
         p->gid = atoi(strtok(NULL, " "));
         p->mode = strtol(strtok(NULL, " "), NULL, 8);   // mode is in octal
         p->capabilities = 0;
diff --git a/logd/LogBufferElement.cpp b/logd/LogBufferElement.cpp
index 81356fe..04a620c 100644
--- a/logd/LogBufferElement.cpp
+++ b/logd/LogBufferElement.cpp
@@ -235,7 +235,9 @@
     }
     iovec[1].iov_len = entry.len;
 
-    log_time retval = reader->sendDatav(iovec, 2) ? FLUSH_ERROR : mRealTime;
+    log_time retval = reader->sendDatav(iovec, 1 + (entry.len != 0))
+                          ? FLUSH_ERROR
+                          : mRealTime;
 
     if (buffer) free(buffer);
 
diff --git a/rootdir/init.rc b/rootdir/init.rc
index 77b173d..28406c8 100644
--- a/rootdir/init.rc
+++ b/rootdir/init.rc
@@ -599,7 +599,7 @@
 
 on nonencrypted
     # A/B update verifier that marks a successful boot.
-    exec - root cache -- /system/bin/update_verifier nonencrypted
+    exec_start update_verifier_nonencrypted
     class_start main
     class_start late_start
 
@@ -622,12 +622,12 @@
 
 on property:vold.decrypt=trigger_restart_min_framework
     # A/B update verifier that marks a successful boot.
-    exec - root cache -- /system/bin/update_verifier trigger_restart_min_framework
+    exec_start update_verifier
     class_start main
 
 on property:vold.decrypt=trigger_restart_framework
     # A/B update verifier that marks a successful boot.
-    exec - root cache -- /system/bin/update_verifier trigger_restart_framework
+    exec_start update_verifier
     class_start main
     class_start late_start
 
diff --git a/tzdatacheck/tzdatacheck.cpp b/tzdatacheck/tzdatacheck.cpp
index 381df5a..8fcd17f 100644
--- a/tzdatacheck/tzdatacheck.cpp
+++ b/tzdatacheck/tzdatacheck.cpp
@@ -30,6 +30,19 @@
 
 #include "android-base/logging.h"
 
+// The name of the directory that holds a staged time zone update distro. If this exists it should
+// replace the one in CURRENT_DIR_NAME.
+// See also libcore.tzdata.update2.TimeZoneDistroInstaller.
+static const char* STAGED_DIR_NAME = "/staged";
+
+// The name of the directory that holds the (optional) installed time zone update distro.
+// See also libcore.tzdata.update2.TimeZoneDistroInstaller.
+static const char* CURRENT_DIR_NAME = "/current";
+
+// The name of a file in the staged dir that indicates the staged operation is an "uninstall".
+// See also libcore.tzdata.update2.TimeZoneDistroInstaller.
+static const char* UNINSTALL_TOMBSTONE_FILE_NAME = "/STAGED_UNINSTALL_TOMBSTONE";
+
 // The name of the file containing the distro version information.
 // See also libcore.tzdata.shared2.TimeZoneDistro / libcore.tzdata.shared2.DistroVersion.
 static const char* DISTRO_VERSION_FILENAME = "/distro_version";
@@ -75,7 +88,6 @@
 static const char TZ_DATA_HEADER_PREFIX[] = "tzdata";
 static const size_t TZ_DATA_HEADER_PREFIX_LEN = sizeof(TZ_DATA_HEADER_PREFIX) - 1; // exclude \0
 
-
 static void usage() {
     std::cerr << "Usage: tzdatacheck SYSTEM_TZ_DIR DATA_TZ_DIR\n"
             "\n"
@@ -184,7 +196,7 @@
     return 0;
 }
 
-enum PathStatus { ERR, NONE, IS_DIR, NOT_DIR };
+enum PathStatus { ERR, NONE, IS_DIR, IS_REG, UNKNOWN };
 
 static PathStatus checkPath(const std::string& path) {
     struct stat buf;
@@ -195,7 +207,31 @@
         }
         return NONE;
     }
-    return S_ISDIR(buf.st_mode) ? IS_DIR : NOT_DIR;
+    return S_ISDIR(buf.st_mode) ? IS_DIR : S_ISREG(buf.st_mode) ? IS_REG : UNKNOWN;
+}
+
+/*
+ * Deletes fileToDelete and returns true if it is successful. If fileToDelete is not a file or
+ * cannot be accessed this method returns false.
+ */
+static bool deleteFile(const std::string& fileToDelete) {
+    // Check whether the file exists.
+    PathStatus pathStatus = checkPath(fileToDelete);
+    if (pathStatus == NONE) {
+        LOG(INFO) << "Path " << fileToDelete << " does not exist";
+        return true;
+    }
+    if (pathStatus != IS_REG) {
+        LOG(WARNING) << "Path " << fileToDelete << " failed to stat() or is not a file.";
+        return false;
+    }
+
+    // Attempt the deletion.
+    int rc = unlink(fileToDelete.c_str());
+    if (rc != 0) {
+        PLOG(WARNING) << "unlink() failed for " << fileToDelete;
+    }
+    return rc == 0;
 }
 
 /*
@@ -260,8 +296,7 @@
     std::string dataUpdatesDirName(dataZoneInfoDir);
     dataUpdatesDirName += "/updates";
     LOG(INFO) << "Removing: " << dataUpdatesDirName;
-    bool deleted = deleteDir(dataUpdatesDirName);
-    if (!deleted) {
+    if (!deleteDir(dataUpdatesDirName)) {
         LOG(WARNING) << "Deletion of install metadata " << dataUpdatesDirName
                 << " was not successful";
     }
@@ -270,14 +305,151 @@
 /*
  * Deletes the timezone update distro directory.
  */
-static void deleteUpdateDistroDir(std::string& distroDirName) {
+static void deleteUpdateDistroDir(const std::string& distroDirName) {
     LOG(INFO) << "Removing: " << distroDirName;
-    bool deleted = deleteDir(distroDirName);
-    if (!deleted) {
+    if (!deleteDir(distroDirName)) {
         LOG(WARNING) << "Deletion of distro dir " << distroDirName << " was not successful";
     }
 }
 
+static void handleStagedUninstall(const std::string& dataStagedDirName,
+                                  const std::string& dataCurrentDirName,
+                                  const PathStatus dataCurrentDirStatus) {
+    LOG(INFO) << "Staged operation is an uninstall.";
+
+    // Delete the current install directory.
+    switch (dataCurrentDirStatus) {
+        case NONE:
+            // This is unexpected: No uninstall should be staged if there is nothing to
+            // uninstall. Carry on anyway.
+            LOG(WARNING) << "No current install to delete.";
+            break;
+        case IS_DIR:
+            // This is normal. Delete the current install dir.
+            if (!deleteDir(dataCurrentDirName)) {
+                LOG(WARNING) << "Deletion of current distro " << dataCurrentDirName
+                             << " was not successful";
+                // If this happens we don't know whether we were able to delete or not. We don't
+                // delete the staged operation so it will be retried next boot unless overridden.
+                return;
+            }
+            break;
+        case IS_REG:
+        default:
+            // This is unexpected: We can try to delete the unexpected file and carry on.
+            LOG(WARNING) << "Current distro dir " << dataCurrentDirName
+                         << " is not actually a directory. Attempting deletion.";
+            if (!deleteFile(dataCurrentDirName)) {
+                LOG(WARNING) << "Could not delete " << dataCurrentDirName;
+                return;
+            }
+            break;
+    }
+
+    // Delete the staged uninstall dir.
+    if (!deleteDir(dataStagedDirName)) {
+        LOG(WARNING) << "Deletion of current distro " << dataCurrentDirName
+                     << " was not successful";
+        // If this happens we don't know whether we were able to delete the staged operation
+        // or not.
+        return;
+    }
+    LOG(INFO) << "Staged uninstall complete.";
+}
+
+static void handleStagedInstall(const std::string& dataStagedDirName,
+                                const std::string& dataCurrentDirName,
+                                const PathStatus dataCurrentDirStatus) {
+    LOG(INFO) << "Staged operation is an install.";
+
+    switch (dataCurrentDirStatus) {
+        case NONE:
+            // This is expected: This is the first install.
+            LOG(INFO) << "No current install to replace.";
+            break;
+        case IS_DIR:
+            // This is expected: We are replacing an existing install.
+            // Delete the current dir so we can replace it.
+            if (!deleteDir(dataCurrentDirName)) {
+                LOG(WARNING) << "Deletion of current distro " << dataCurrentDirName
+                             << " was not successful";
+                // If this happens, we cannot proceed.
+                return;
+            }
+            break;
+        case IS_REG:
+        default:
+            // This is unexpected: We can try to delete the unexpected file and carry on.
+            LOG(WARNING) << "Current distro dir " << dataCurrentDirName
+                         << " is not actually a directory. Attempting deletion.";
+            if (!deleteFile(dataCurrentDirName)) {
+                LOG(WARNING) << "Could not delete " << dataCurrentDirName;
+                return;
+            }
+            break;
+    }
+
+    // Move the staged dir so it is the new current dir, completing the install.
+    LOG(INFO) << "Moving " << dataStagedDirName << " to " << dataCurrentDirName;
+    int rc = rename(dataStagedDirName.c_str(), dataCurrentDirName.c_str());
+    if (rc == -1) {
+        PLOG(WARNING) << "Unable to rename directory from " << dataStagedDirName << " to "
+                      << &dataCurrentDirName[0];
+        return;
+    }
+
+    LOG(INFO) << "Staged install complete.";
+}
+/*
+ * Process a staged operation if there is one.
+ */
+static void processStagedOperation(const std::string& dataStagedDirName,
+                                   const std::string& dataCurrentDirName) {
+    PathStatus dataStagedDirStatus = checkPath(dataStagedDirName);
+
+    // Exit early for the common case.
+    if (dataStagedDirStatus == NONE) {
+        LOG(DEBUG) << "No staged time zone operation.";
+        return;
+    }
+
+    // Check known directory names are in a good starting state.
+    if (dataStagedDirStatus != IS_DIR) {
+        LOG(WARNING) << "Staged distro dir " << dataStagedDirName
+                     << " could not be accessed or is not a directory."
+                     << " stagedDirStatus=" << dataStagedDirStatus;
+        return;
+    }
+
+    // dataStagedDirStatus == IS_DIR.
+
+    // Work out whether there is anything currently installed.
+    PathStatus dataCurrentDirStatus = checkPath(dataCurrentDirName);
+    if (dataCurrentDirStatus == ERR) {
+        LOG(WARNING) << "Current install dir " << dataCurrentDirName << " could not be accessed"
+                     << " dataCurrentDirStatus=" << dataCurrentDirStatus;
+        return;
+    }
+
+    // We must perform the staged operation.
+
+    // Check to see if the staged directory contains an uninstall or an install operation.
+    std::string uninstallTombStoneFile(dataStagedDirName);
+    uninstallTombStoneFile += UNINSTALL_TOMBSTONE_FILE_NAME;
+    int uninstallTombStoneFileStatus = checkPath(uninstallTombStoneFile);
+    if (uninstallTombStoneFileStatus != IS_REG && uninstallTombStoneFileStatus != NONE) {
+        // Error case.
+        LOG(WARNING) << "Unable to determine if the staged operation is an uninstall.";
+        return;
+    }
+    if (uninstallTombStoneFileStatus == IS_REG) {
+        handleStagedUninstall(dataStagedDirName, dataCurrentDirName, dataCurrentDirStatus);
+    } else {
+        // uninstallTombStoneFileStatus == NONE meaning this is a staged install.
+        handleStagedInstall(dataStagedDirName, dataCurrentDirName, dataCurrentDirStatus);
+    }
+}
+
 /*
  * After a platform update it is likely that timezone data found on the system partition will be
  * newer than the version found in the data partition. This tool detects this case and removes the
@@ -300,15 +472,25 @@
     const char* systemZoneInfoDir = argv[1];
     const char* dataZoneInfoDir = argv[2];
 
-    // Check the distro directory exists. If it does not, exit quickly: nothing to do.
+    std::string dataStagedDirName(dataZoneInfoDir);
+    dataStagedDirName += STAGED_DIR_NAME;
+
     std::string dataCurrentDirName(dataZoneInfoDir);
-    dataCurrentDirName += "/current";
-    int dataCurrentDirStatus = checkPath(dataCurrentDirName);
+    dataCurrentDirName += CURRENT_DIR_NAME;
+
+    // Check for an process any staged operation.
+    // If the staged operation could not be handled we still have to validate the current installed
+    // directory so we do not check for errors and do not quit early.
+    processStagedOperation(dataStagedDirName, dataCurrentDirName);
+
+    // Check the distro directory exists. If it does not, exit quickly: nothing to do.
+    PathStatus dataCurrentDirStatus = checkPath(dataCurrentDirName);
     if (dataCurrentDirStatus == NONE) {
         LOG(INFO) << "timezone distro dir " << dataCurrentDirName
                 << " does not exist. No action required.";
         return 0;
     }
+
     // If the distro directory path is not a directory or we can't stat() the path, exit with a
     // warning: either there's a problem accessing storage or the world is not as it should be;
     // nothing to do.