diff --git a/libbacktrace/include/backtrace/Backtrace.h b/libbacktrace/include/backtrace/Backtrace.h
index 735a2f3..10e790b 100644
--- a/libbacktrace/include/backtrace/Backtrace.h
+++ b/libbacktrace/include/backtrace/Backtrace.h
@@ -122,7 +122,7 @@
   // Tracing a thread in a different process is not supported.
   // If map is NULL, then create the map and manage it internally.
   // If map is not NULL, the map is still owned by the caller.
-  static Backtrace* Create(pid_t pid, pid_t tid, BacktraceMap* map = NULL);
+  static Backtrace* Create(pid_t pid, pid_t tid, BacktraceMap* map = nullptr);
 
   // Create an offline Backtrace object that can be used to do an unwind without a process
   // that is still running. By default, information is only cached in the map
@@ -145,7 +145,7 @@
   virtual ~Backtrace();
 
   // Get the current stack trace and store in the backtrace_ structure.
-  virtual bool Unwind(size_t num_ignore_frames, void* context = NULL) = 0;
+  virtual bool Unwind(size_t num_ignore_frames, void* context = nullptr) = 0;
 
   static bool Unwind(unwindstack::Regs* regs, BacktraceMap* back_map,
                      std::vector<backtrace_frame_data_t>* frames, size_t num_ignore_frames,
@@ -160,7 +160,7 @@
   // If the string is empty, then no valid function name was found,
   // or the pc is not in any valid map.
   virtual std::string GetFunctionName(uint64_t pc, uint64_t* offset,
-                                      const backtrace_map_t* map = NULL);
+                                      const backtrace_map_t* map = nullptr);
 
   // Fill in the map data associated with the given pc.
   virtual void FillInMap(uint64_t pc, backtrace_map_t* map);
@@ -185,7 +185,7 @@
 
   const backtrace_frame_data_t* GetFrame(size_t frame_num) {
     if (frame_num >= frames_.size()) {
-      return NULL;
+      return nullptr;
     }
     return &frames_[frame_num];
   }
diff --git a/libutils/FileMap.cpp b/libutils/FileMap.cpp
index 3c4d81c..583c6b9 100644
--- a/libutils/FileMap.cpp
+++ b/libutils/FileMap.cpp
@@ -48,10 +48,10 @@
 
 // Constructor.  Create an empty object.
 FileMap::FileMap(void)
-    : mFileName(NULL),
-      mBasePtr(NULL),
+    : mFileName(nullptr),
+      mBasePtr(nullptr),
       mBaseLength(0),
-      mDataPtr(NULL),
+      mDataPtr(nullptr),
       mDataLength(0)
 #if defined(__MINGW32__)
       ,
@@ -69,9 +69,9 @@
       , mFileHandle(other.mFileHandle), mFileMapping(other.mFileMapping)
 #endif
 {
-    other.mFileName = NULL;
-    other.mBasePtr = NULL;
-    other.mDataPtr = NULL;
+    other.mFileName = nullptr;
+    other.mBasePtr = nullptr;
+    other.mDataPtr = nullptr;
 #if defined(__MINGW32__)
     other.mFileHandle = INVALID_HANDLE_VALUE;
     other.mFileMapping = NULL;
@@ -86,9 +86,9 @@
     mDataOffset = other.mDataOffset;
     mDataPtr = other.mDataPtr;
     mDataLength = other.mDataLength;
-    other.mFileName = NULL;
-    other.mBasePtr = NULL;
-    other.mDataPtr = NULL;
+    other.mFileName = nullptr;
+    other.mBasePtr = nullptr;
+    other.mDataPtr = nullptr;
 #if defined(__MINGW32__)
     mFileHandle = other.mFileHandle;
     mFileMapping = other.mFileMapping;
@@ -101,7 +101,7 @@
 // Destructor.
 FileMap::~FileMap(void)
 {
-    if (mFileName != NULL) {
+    if (mFileName != nullptr) {
         free(mFileName);
     }
 #if defined(__MINGW32__)
@@ -196,7 +196,7 @@
     if (!readOnly)
         prot |= PROT_WRITE;
 
-    ptr = mmap(NULL, adjLength, prot, flags, fd, adjOffset);
+    ptr = mmap(nullptr, adjLength, prot, flags, fd, adjOffset);
     if (ptr == MAP_FAILED) {
         ALOGE("mmap(%lld,%zu) failed: %s\n",
             (long long)adjOffset, adjLength, strerror(errno));
@@ -205,7 +205,7 @@
     mBasePtr = ptr;
 #endif // !defined(__MINGW32__)
 
-    mFileName = origFileName != NULL ? strdup(origFileName) : NULL;
+    mFileName = origFileName != nullptr ? strdup(origFileName) : nullptr;
     mBaseLength = adjLength;
     mDataOffset = offset;
     mDataPtr = (char*) mBasePtr + adjust;
diff --git a/libutils/Looper.cpp b/libutils/Looper.cpp
index 6c57b2e..7bc2397 100644
--- a/libutils/Looper.cpp
+++ b/libutils/Looper.cpp
@@ -29,7 +29,7 @@
 
 void WeakMessageHandler::handleMessage(const Message& message) {
     sp<MessageHandler> handler = mHandler.promote();
-    if (handler != NULL) {
+    if (handler != nullptr) {
         handler->handleMessage(message);
     }
 }
@@ -87,7 +87,7 @@
 
 void Looper::threadDestructor(void *st) {
     Looper* const self = static_cast<Looper*>(st);
-    if (self != NULL) {
+    if (self != nullptr) {
         self->decStrong((void*)threadDestructor);
     }
 }
@@ -95,13 +95,13 @@
 void Looper::setForThread(const sp<Looper>& looper) {
     sp<Looper> old = getForThread(); // also has side-effect of initializing TLS
 
-    if (looper != NULL) {
+    if (looper != nullptr) {
         looper->incStrong((void*)threadDestructor);
     }
 
     pthread_setspecific(gTLSKey, looper.get());
 
-    if (old != NULL) {
+    if (old != nullptr) {
         old->decStrong((void*)threadDestructor);
     }
 }
@@ -116,7 +116,7 @@
 sp<Looper> Looper::prepare(int opts) {
     bool allowNonCallbacks = opts & PREPARE_ALLOW_NON_CALLBACKS;
     sp<Looper> looper = Looper::getForThread();
-    if (looper == NULL) {
+    if (looper == nullptr) {
         looper = new Looper(allowNonCallbacks);
         Looper::setForThread(looper);
     }
@@ -190,9 +190,9 @@
                         "fd=%d, events=0x%x, data=%p",
                         this, ident, fd, events, data);
 #endif
-                if (outFd != NULL) *outFd = fd;
-                if (outEvents != NULL) *outEvents = events;
-                if (outData != NULL) *outData = data;
+                if (outFd != nullptr) *outFd = fd;
+                if (outEvents != nullptr) *outEvents = events;
+                if (outData != nullptr) *outData = data;
                 return ident;
             }
         }
@@ -201,9 +201,9 @@
 #if DEBUG_POLL_AND_WAKE
             ALOGD("%p ~ pollOnce - returning result %d", this, result);
 #endif
-            if (outFd != NULL) *outFd = 0;
-            if (outEvents != NULL) *outEvents = 0;
-            if (outData != NULL) *outData = NULL;
+            if (outFd != nullptr) *outFd = 0;
+            if (outEvents != nullptr) *outEvents = 0;
+            if (outData != nullptr) *outData = nullptr;
             return result;
         }
 
@@ -427,7 +427,7 @@
 }
 
 int Looper::addFd(int fd, int ident, int events, Looper_callbackFunc callback, void* data) {
-    return addFd(fd, ident, events, callback ? new SimpleLooperCallback(callback) : NULL, data);
+    return addFd(fd, ident, events, callback ? new SimpleLooperCallback(callback) : nullptr, data);
 }
 
 int Looper::addFd(int fd, int ident, int events, const sp<LooperCallback>& callback, void* data) {
@@ -542,7 +542,7 @@
         // updating the epoll set so that we avoid accidentally leaking callbacks.
         mRequests.removeItemsAt(requestIndex);
 
-        int epollResult = epoll_ctl(mEpollFd, EPOLL_CTL_DEL, fd, NULL);
+        int epollResult = epoll_ctl(mEpollFd, EPOLL_CTL_DEL, fd, nullptr);
         if (epollResult < 0) {
             if (seq != -1 && (errno == EBADF || errno == ENOENT)) {
                 // Tolerate EBADF or ENOENT when the sequence number is known because it
diff --git a/libutils/NativeHandle.cpp b/libutils/NativeHandle.cpp
index 97d06b8..d437a9f 100644
--- a/libutils/NativeHandle.cpp
+++ b/libutils/NativeHandle.cpp
@@ -20,7 +20,7 @@
 namespace android {
 
 sp<NativeHandle> NativeHandle::create(native_handle_t* handle, bool ownsHandle) {
-    return handle ? new NativeHandle(handle, ownsHandle) : NULL;
+    return handle ? new NativeHandle(handle, ownsHandle) : nullptr;
 }
 
 NativeHandle::NativeHandle(native_handle_t* handle, bool ownsHandle)
diff --git a/libutils/Printer.cpp b/libutils/Printer.cpp
index cbf042e..c9ae210 100644
--- a/libutils/Printer.cpp
+++ b/libutils/Printer.cpp
@@ -73,7 +73,7 @@
 }
 
 void LogPrinter::printLine(const char* string) {
-    if (string == NULL) {
+    if (string == nullptr) {
         ALOGW("%s: NULL string passed in", __FUNCTION__);
         return;
     }
@@ -107,7 +107,7 @@
 }
 
 void FdPrinter::printLine(const char* string) {
-    if (string == NULL) {
+    if (string == nullptr) {
         ALOGW("%s: NULL string passed in", __FUNCTION__);
         return;
     } else if (mFd < 0) {
@@ -127,16 +127,16 @@
         mTarget(target),
         mPrefix(prefix ?: "") {
 
-    if (target == NULL) {
+    if (target == nullptr) {
         ALOGW("%s: Target string was NULL", __FUNCTION__);
     }
 }
 
 void String8Printer::printLine(const char* string) {
-    if (string == NULL) {
+    if (string == nullptr) {
         ALOGW("%s: NULL string passed in", __FUNCTION__);
         return;
-    } else if (mTarget == NULL) {
+    } else if (mTarget == nullptr) {
         ALOGW("%s: Target string was NULL", __FUNCTION__);
         return;
     }
diff --git a/libutils/ProcessCallStack.cpp b/libutils/ProcessCallStack.cpp
index b8fb6dc..f054de9 100644
--- a/libutils/ProcessCallStack.cpp
+++ b/libutils/ProcessCallStack.cpp
@@ -42,14 +42,14 @@
 static const char* PATH_SELF_TASK = "/proc/self/task";
 
 static void dumpProcessHeader(Printer& printer, pid_t pid, const char* timeStr) {
-    if (timeStr == NULL) {
+    if (timeStr == nullptr) {
         ALOGW("%s: timeStr was NULL", __FUNCTION__);
         return;
     }
 
     char path[PATH_MAX];
     char procNameBuf[MAX_PROC_PATH];
-    char* procName = NULL;
+    char* procName = nullptr;
     FILE* fp;
 
     snprintf(path, sizeof(path), "/proc/%d/cmdline", pid);
@@ -76,7 +76,7 @@
 
 static String8 getThreadName(pid_t tid) {
     char path[PATH_MAX];
-    char* procName = NULL;
+    char* procName = nullptr;
     char procNameBuf[MAX_PROC_PATH];
     FILE* fp;
 
@@ -88,7 +88,7 @@
         ALOGE("%s: Failed to open %s", __FUNCTION__, path);
     }
 
-    if (procName == NULL) {
+    if (procName == nullptr) {
         // Reading /proc/self/task/%d/comm failed due to a race
         return String8::format("[err-unknown-tid-%d]", tid);
     }
@@ -128,7 +128,7 @@
 
 void ProcessCallStack::update() {
     std::unique_ptr<DIR, decltype(&closedir)> dp(opendir(PATH_SELF_TASK), closedir);
-    if (dp == NULL) {
+    if (dp == nullptr) {
         ALOGE("%s: Failed to update the process's call stacks: %s",
               __FUNCTION__, strerror(errno));
         return;
@@ -140,7 +140,7 @@
 
     // Get current time.
     {
-        time_t t = time(NULL);
+        time_t t = time(nullptr);
         struct tm tm;
         localtime_r(&t, &tm);
 
@@ -152,7 +152,7 @@
      * - Read every file in directory => get every tid
      */
     dirent* ep;
-    while ((ep = readdir(dp.get())) != NULL) {
+    while ((ep = readdir(dp.get())) != nullptr) {
         pid_t tid = -1;
         sscanf(ep->d_name, "%d", &tid);
 
diff --git a/libutils/PropertyMap.cpp b/libutils/PropertyMap.cpp
index 4bcdd0f..b8c065d 100644
--- a/libutils/PropertyMap.cpp
+++ b/libutils/PropertyMap.cpp
@@ -112,7 +112,7 @@
 }
 
 status_t PropertyMap::load(const String8& filename, PropertyMap** outMap) {
-    *outMap = NULL;
+    *outMap = nullptr;
 
     Tokenizer* tokenizer;
     status_t status = Tokenizer::open(filename, &tokenizer);
diff --git a/libutils/RefBase.cpp b/libutils/RefBase.cpp
index 8bccb0f..9074850 100644
--- a/libutils/RefBase.cpp
+++ b/libutils/RefBase.cpp
@@ -712,7 +712,7 @@
         delete mRefs;
     }
     // For debugging purposes, clear mRefs.  Ineffective against outstanding wp's.
-    const_cast<weakref_impl*&>(mRefs) = NULL;
+    const_cast<weakref_impl*&>(mRefs) = nullptr;
 }
 
 void RefBase::extendObjectLifetime(int32_t mode)
diff --git a/libutils/SharedBuffer.cpp b/libutils/SharedBuffer.cpp
index bad98b2..7910c6e 100644
--- a/libutils/SharedBuffer.cpp
+++ b/libutils/SharedBuffer.cpp
@@ -75,7 +75,7 @@
                             "Invalid buffer size %zu", newSize);
 
         buf = (SharedBuffer*)realloc(buf, sizeof(SharedBuffer) + newSize);
-        if (buf != NULL) {
+        if (buf != nullptr) {
             buf->mSize = newSize;
             return buf;
         }
@@ -94,7 +94,7 @@
     if (onlyOwner()) {
         return const_cast<SharedBuffer*>(this);
     }
-    return 0;
+    return nullptr;
 }
 
 SharedBuffer* SharedBuffer::reset(size_t new_size) const
diff --git a/libutils/SharedBuffer.h b/libutils/SharedBuffer.h
index 81cadff..fdf13a9 100644
--- a/libutils/SharedBuffer.h
+++ b/libutils/SharedBuffer.h
@@ -124,11 +124,11 @@
 }
 
 SharedBuffer* SharedBuffer::bufferFromData(void* data) {
-    return data ? static_cast<SharedBuffer *>(data)-1 : 0;
+    return data ? static_cast<SharedBuffer *>(data)-1 : nullptr;
 }
     
 const SharedBuffer* SharedBuffer::bufferFromData(const void* data) {
-    return data ? static_cast<const SharedBuffer *>(data)-1 : 0;
+    return data ? static_cast<const SharedBuffer *>(data)-1 : nullptr;
 }
 
 size_t SharedBuffer::sizeFromData(const void* data) {
diff --git a/libutils/String16.cpp b/libutils/String16.cpp
index 230e970..5c0b406 100644
--- a/libutils/String16.cpp
+++ b/libutils/String16.cpp
@@ -91,7 +91,7 @@
 }
 
 String16::String16(StaticLinkage)
-    : mString(0)
+    : mString(nullptr)
 {
     // this constructor is used when we can't rely on the static-initializers
     // having run. In this case we always allocate an empty string. It's less
@@ -342,7 +342,7 @@
 {
     const size_t N = size();
     const char16_t* str = string();
-    char16_t* edit = NULL;
+    char16_t* edit = nullptr;
     for (size_t i=0; i<N; i++) {
         const char16_t v = str[i];
         if (v >= 'A' && v <= 'Z') {
@@ -364,7 +364,7 @@
 {
     const size_t N = size();
     const char16_t* str = string();
-    char16_t* edit = NULL;
+    char16_t* edit = nullptr;
     for (size_t i=0; i<N; i++) {
         if (str[i] == replaceThis) {
             if (!edit) {
diff --git a/libutils/String8.cpp b/libutils/String8.cpp
index 580e870..8d318f7 100644
--- a/libutils/String8.cpp
+++ b/libutils/String8.cpp
@@ -58,7 +58,7 @@
 {
     if (len > 0) {
         if (len == SIZE_MAX) {
-            return NULL;
+            return nullptr;
         }
         SharedBuffer* buf = SharedBuffer::alloc(len+1);
         ALOG_ASSERT(buf, "Unable to allocate shared buffer");
@@ -68,7 +68,7 @@
             str[len] = 0;
             return str;
         }
-        return NULL;
+        return nullptr;
     }
 
     return getEmptyString();
@@ -126,7 +126,7 @@
 }
 
 String8::String8(StaticLinkage)
-    : mString(0)
+    : mString(nullptr)
 {
     // this constructor is used when we can't rely on the static-initializers
     // having run. In this case we always allocate an empty string. It's less
@@ -147,7 +147,7 @@
 String8::String8(const char* o)
     : mString(allocFromUTF8(o, strlen(o)))
 {
-    if (mString == NULL) {
+    if (mString == nullptr) {
         mString = getEmptyString();
     }
 }
@@ -155,7 +155,7 @@
 String8::String8(const char* o, size_t len)
     : mString(allocFromUTF8(o, len))
 {
-    if (mString == NULL) {
+    if (mString == nullptr) {
         mString = getEmptyString();
     }
 }
@@ -319,7 +319,7 @@
      * second vsnprintf access undefined args.
      */
     va_copy(tmp_args, args);
-    n = vsnprintf(NULL, 0, fmt, tmp_args);
+    n = vsnprintf(nullptr, 0, fmt, tmp_args);
     va_end(tmp_args);
 
     if (n != 0) {
@@ -360,7 +360,7 @@
         mString = str;
         return str;
     }
-    return NULL;
+    return nullptr;
 }
 
 void String8::unlockBuffer()
@@ -512,7 +512,7 @@
     const char*const buf = mString;
 
     cp = strrchr(buf, OS_PATH_SEPARATOR);
-    if (cp == NULL)
+    if (cp == nullptr)
         return String8(*this);
     else
         return String8(cp+1);
@@ -524,7 +524,7 @@
     const char*const str = mString;
 
     cp = strrchr(str, OS_PATH_SEPARATOR);
-    if (cp == NULL)
+    if (cp == nullptr)
         return String8("");
     else
         return String8(str, cp - str);
@@ -543,7 +543,7 @@
         cp = strchr(buf, OS_PATH_SEPARATOR);
     }
 
-    if (cp == NULL) {
+    if (cp == nullptr) {
         String8 res = buf != str ? String8(buf) : *this;
         if (outRemains) *outRemains = String8("");
         return res;
@@ -567,15 +567,15 @@
 
     // only look at the filename
     lastSlash = strrchr(str, OS_PATH_SEPARATOR);
-    if (lastSlash == NULL)
+    if (lastSlash == nullptr)
         lastSlash = str;
     else
         lastSlash++;
 
     // find the last dot
     lastDot = strrchr(lastSlash, '.');
-    if (lastDot == NULL)
-        return NULL;
+    if (lastDot == nullptr)
+        return nullptr;
 
     // looks good, ship it
     return const_cast<char*>(lastDot);
@@ -586,7 +586,7 @@
     char* ext;
 
     ext = find_extension();
-    if (ext != NULL)
+    if (ext != nullptr)
         return String8(ext);
     else
         return String8("");
@@ -598,7 +598,7 @@
     const char* const str = mString;
 
     ext = find_extension();
-    if (ext == NULL)
+    if (ext == nullptr)
         return String8(*this);
     else
         return String8(str, ext - str);
diff --git a/libutils/Threads.cpp b/libutils/Threads.cpp
index 7d7f0e2..43ec6c1 100644
--- a/libutils/Threads.cpp
+++ b/libutils/Threads.cpp
@@ -163,7 +163,7 @@
     // Note that *threadID is directly available to the parent only, as it is
     // assigned after the child starts.  Use memory barrier / lock if the child
     // or other threads also need access.
-    if (threadId != NULL) {
+    if (threadId != nullptr) {
         *threadId = (android_thread_id_t)thread; // XXX: this is not portable
     }
     return 1;
@@ -768,7 +768,7 @@
         strong.clear();
         // And immediately, re-acquire a strong reference for the next loop
         strong = weak.promote();
-    } while(strong != 0);
+    } while(strong != nullptr);
 
     return 0;
 }
diff --git a/libutils/Timers.cpp b/libutils/Timers.cpp
index b2df9a5..c3641ef 100644
--- a/libutils/Timers.cpp
+++ b/libutils/Timers.cpp
@@ -45,7 +45,7 @@
     // is windows.
     struct timeval t;
     t.tv_sec = t.tv_usec = 0;
-    gettimeofday(&t, NULL);
+    gettimeofday(&t, nullptr);
     return nsecs_t(t.tv_sec)*1000000000LL + nsecs_t(t.tv_usec)*1000LL;
 }
 #endif
diff --git a/libutils/Tokenizer.cpp b/libutils/Tokenizer.cpp
index b68a2cf..f73d699 100644
--- a/libutils/Tokenizer.cpp
+++ b/libutils/Tokenizer.cpp
@@ -28,7 +28,7 @@
 namespace android {
 
 static inline bool isDelimiter(char ch, const char* delimiters) {
-    return strchr(delimiters, ch) != NULL;
+    return strchr(delimiters, ch) != nullptr;
 }
 
 Tokenizer::Tokenizer(const String8& filename, FileMap* fileMap, char* buffer,
@@ -46,7 +46,7 @@
 }
 
 status_t Tokenizer::open(const String8& filename, Tokenizer** outTokenizer) {
-    *outTokenizer = NULL;
+    *outTokenizer = nullptr;
 
     int result = NO_ERROR;
     int fd = ::open(filename.string(), O_RDONLY);
@@ -64,12 +64,12 @@
             FileMap* fileMap = new FileMap();
             bool ownBuffer = false;
             char* buffer;
-            if (fileMap->create(NULL, fd, 0, length, true)) {
+            if (fileMap->create(nullptr, fd, 0, length, true)) {
                 fileMap->advise(FileMap::SEQUENTIAL);
                 buffer = static_cast<char*>(fileMap->getDataPtr());
             } else {
                 delete fileMap;
-                fileMap = NULL;
+                fileMap = nullptr;
 
                 // Fall back to reading into a buffer since we can't mmap files in sysfs.
                 // The length we obtained from stat is wrong too (it will always be 4096)
@@ -81,7 +81,7 @@
                     result = -errno;
                     ALOGE("Error reading file '%s': %s", filename.string(), strerror(errno));
                     delete[] buffer;
-                    buffer = NULL;
+                    buffer = nullptr;
                 } else {
                     length = size_t(nrd);
                 }
@@ -98,7 +98,7 @@
 
 status_t Tokenizer::fromContents(const String8& filename,
         const char* contents, Tokenizer** outTokenizer) {
-    *outTokenizer = new Tokenizer(filename, NULL,
+    *outTokenizer = new Tokenizer(filename, nullptr,
             const_cast<char*>(contents), false, strlen(contents));
     return OK;
 }
diff --git a/libutils/Unicode.cpp b/libutils/Unicode.cpp
index 1086831..e00fb81 100644
--- a/libutils/Unicode.cpp
+++ b/libutils/Unicode.cpp
@@ -159,7 +159,7 @@
         return -1;
     }
     size_t dummy_index;
-    if (next_index == NULL) {
+    if (next_index == nullptr) {
         next_index = &dummy_index;
     }
     size_t num_read;
@@ -173,7 +173,7 @@
 
 ssize_t utf32_to_utf8_length(const char32_t *src, size_t src_len)
 {
-    if (src == NULL || src_len == 0) {
+    if (src == nullptr || src_len == 0) {
         return -1;
     }
 
@@ -195,7 +195,7 @@
 
 void utf32_to_utf8(const char32_t* src, size_t src_len, char* dst, size_t dst_len)
 {
-    if (src == NULL || src_len == 0 || dst == NULL) {
+    if (src == nullptr || src_len == 0 || dst == nullptr) {
         return;
     }
 
@@ -363,7 +363,7 @@
 
 void utf16_to_utf8(const char16_t* src, size_t src_len, char* dst, size_t dst_len)
 {
-    if (src == NULL || src_len == 0 || dst == NULL) {
+    if (src == nullptr || src_len == 0 || dst == nullptr) {
         return;
     }
 
@@ -440,7 +440,7 @@
 
 ssize_t utf16_to_utf8_length(const char16_t *src, size_t src_len)
 {
-    if (src == NULL || src_len == 0) {
+    if (src == nullptr || src_len == 0) {
         return -1;
     }
 
@@ -490,7 +490,7 @@
 
 size_t utf8_to_utf32_length(const char *src, size_t src_len)
 {
-    if (src == NULL || src_len == 0) {
+    if (src == nullptr || src_len == 0) {
         return 0;
     }
     size_t ret = 0;
@@ -515,7 +515,7 @@
 
 void utf8_to_utf32(const char* src, size_t src_len, char32_t* dst)
 {
-    if (src == NULL || src_len == 0 || dst == NULL) {
+    if (src == nullptr || src_len == 0 || dst == nullptr) {
         return;
     }
 
diff --git a/libutils/VectorImpl.cpp b/libutils/VectorImpl.cpp
index ef3277f..00a904d 100644
--- a/libutils/VectorImpl.cpp
+++ b/libutils/VectorImpl.cpp
@@ -44,7 +44,7 @@
 // ----------------------------------------------------------------------------
 
 VectorImpl::VectorImpl(size_t itemSize, uint32_t flags)
-    : mStorage(0), mCount(0), mFlags(flags), mItemSize(itemSize)
+    : mStorage(nullptr), mCount(0), mFlags(flags), mItemSize(itemSize)
 {
 }
 
@@ -77,7 +77,7 @@
             mCount = rhs.mCount;
             SharedBuffer::bufferFromData(mStorage)->acquire();
         } else {
-            mStorage = 0;
+            mStorage = nullptr;
             mCount = 0;
         }
     }
@@ -89,14 +89,14 @@
     if (mStorage) {
         const SharedBuffer* sb = SharedBuffer::bufferFromData(mStorage);
         SharedBuffer* editable = sb->attemptEdit();
-        if (editable == 0) {
+        if (editable == nullptr) {
             // If we're here, we're not the only owner of the buffer.
             // We must make a copy of it.
             editable = SharedBuffer::alloc(sb->size());
             // Fail instead of returning a pointer to storage that's not
             // editable. Otherwise we'd be editing the contents of a buffer
             // for which we're not the only owner, which is undefined behaviour.
-            LOG_ALWAYS_FATAL_IF(editable == NULL);
+            LOG_ALWAYS_FATAL_IF(editable == nullptr);
             _do_copy(editable->data(), mStorage, mCount);
             release_storage();
             mStorage = editable->data();
@@ -141,7 +141,7 @@
 
 ssize_t VectorImpl::insertAt(size_t index, size_t numItems)
 {
-    return insertAt(0, index, numItems);
+    return insertAt(nullptr, index, numItems);
 }
 
 ssize_t VectorImpl::insertAt(const void* item, size_t index, size_t numItems)
@@ -177,7 +177,7 @@
     const ssize_t count = size();
     if (count > 1) {
         void* array = const_cast<void*>(arrayImpl());
-        void* temp = 0;
+        void* temp = nullptr;
         ssize_t i = 1;
         while (i < count) {
             void* item = reinterpret_cast<char*>(array) + mItemSize*(i);
@@ -205,7 +205,7 @@
                     _do_copy(next, curr, 1);
                     next = curr;
                     --j;
-                    curr = NULL;
+                    curr = nullptr;
                     if (j >= 0) {
                         curr = reinterpret_cast<char*>(array) + mItemSize*(j);
                     }
@@ -233,7 +233,7 @@
 
 void VectorImpl::push()
 {
-    push(0);
+    push(nullptr);
 }
 
 void VectorImpl::push(const void* item)
@@ -243,7 +243,7 @@
 
 ssize_t VectorImpl::add()
 {
-    return add(0);
+    return add(nullptr);
 }
 
 ssize_t VectorImpl::add(const void* item)
@@ -253,7 +253,7 @@
 
 ssize_t VectorImpl::replaceAt(size_t index)
 {
-    return replaceAt(0, index);
+    return replaceAt(nullptr, index);
 }
 
 ssize_t VectorImpl::replaceAt(const void* prototype, size_t index)
@@ -267,10 +267,10 @@
 
     void* item = editItemLocation(index);
     if (item != prototype) {
-        if (item == 0)
+        if (item == nullptr)
             return NO_MEMORY;
         _do_destroy(item, 1);
-        if (prototype == 0) {
+        if (prototype == nullptr) {
             _do_construct(item, 1);
         } else {
             _do_copy(item, prototype, 1);
@@ -294,7 +294,7 @@
 void VectorImpl::finish_vector()
 {
     release_storage();
-    mStorage = 0;
+    mStorage = nullptr;
     mCount = 0;
 }
 
@@ -315,7 +315,7 @@
             return reinterpret_cast<char*>(buffer) + index*mItemSize;
         }
     }
-    return 0;
+    return nullptr;
 }
 
 const void* VectorImpl::itemLocation(size_t index) const
@@ -330,7 +330,7 @@
             return reinterpret_cast<const char*>(buffer) + index*mItemSize;
         }
     }
-    return 0;
+    return nullptr;
 }
 
 ssize_t VectorImpl::setCapacity(size_t new_capacity)
@@ -418,7 +418,7 @@
             if (sb) {
                 mStorage = sb->data();
             } else {
-                return NULL;
+                return nullptr;
             }
         } else {
             SharedBuffer* sb = SharedBuffer::alloc(new_alloc_size);
@@ -435,7 +435,7 @@
                 release_storage();
                 mStorage = const_cast<void*>(array);
             } else {
-                return NULL;
+                return nullptr;
             }
         }
     } else {
diff --git a/libutils/include/utils/Condition.h b/libutils/include/utils/Condition.h
index c8da67c..540ed82 100644
--- a/libutils/include/utils/Condition.h
+++ b/libutils/include/utils/Condition.h
@@ -124,7 +124,7 @@
 #else // __APPLE__
     // Apple doesn't support POSIX clocks.
     struct timeval t;
-    gettimeofday(&t, NULL);
+    gettimeofday(&t, nullptr);
     ts.tv_sec = t.tv_sec;
     ts.tv_nsec = t.tv_usec*1000;
 #endif
diff --git a/libutils/include/utils/LruCache.h b/libutils/include/utils/LruCache.h
index 89dccd6..36775d0 100644
--- a/libutils/include/utils/LruCache.h
+++ b/libutils/include/utils/LruCache.h
@@ -71,7 +71,7 @@
         Entry* parent;
         Entry* child;
 
-        Entry(TKey _key, TValue _value) : key(_key), value(_value), parent(NULL), child(NULL) {
+        Entry(TKey _key, TValue _value) : key(_key), value(_value), parent(nullptr), child(nullptr) {
         }
         const TKey& getKey() const final { return key; }
     };
@@ -162,9 +162,9 @@
 template <typename TKey, typename TValue>
 LruCache<TKey, TValue>::LruCache(uint32_t maxCapacity)
     : mSet(new LruCacheSet())
-    , mListener(NULL)
-    , mOldest(NULL)
-    , mYoungest(NULL)
+    , mListener(nullptr)
+    , mOldest(nullptr)
+    , mYoungest(nullptr)
     , mMaxCapacity(maxCapacity)
     , mNullValue(0) {
     mSet->max_load_factor(1.0);
@@ -236,7 +236,7 @@
 
 template <typename TKey, typename TValue>
 bool LruCache<TKey, TValue>::removeOldest() {
-    if (mOldest != NULL) {
+    if (mOldest != nullptr) {
         return remove(mOldest->key);
         // TODO: should probably abort if false
     }
@@ -254,12 +254,12 @@
 template <typename TKey, typename TValue>
 void LruCache<TKey, TValue>::clear() {
     if (mListener) {
-        for (Entry* p = mOldest; p != NULL; p = p->child) {
+        for (Entry* p = mOldest; p != nullptr; p = p->child) {
             (*mListener)(p->key, p->value);
         }
     }
-    mYoungest = NULL;
-    mOldest = NULL;
+    mYoungest = nullptr;
+    mOldest = nullptr;
     for (auto entry : *mSet.get()) {
         delete entry;
     }
@@ -268,7 +268,7 @@
 
 template <typename TKey, typename TValue>
 void LruCache<TKey, TValue>::attachToCache(Entry& entry) {
-    if (mYoungest == NULL) {
+    if (mYoungest == nullptr) {
         mYoungest = mOldest = &entry;
     } else {
         entry.parent = mYoungest;
@@ -279,19 +279,19 @@
 
 template <typename TKey, typename TValue>
 void LruCache<TKey, TValue>::detachFromCache(Entry& entry) {
-    if (entry.parent != NULL) {
+    if (entry.parent != nullptr) {
         entry.parent->child = entry.child;
     } else {
         mOldest = entry.child;
     }
-    if (entry.child != NULL) {
+    if (entry.child != nullptr) {
         entry.child->parent = entry.parent;
     } else {
         mYoungest = entry.parent;
     }
 
-    entry.parent = NULL;
-    entry.child = NULL;
+    entry.parent = nullptr;
+    entry.child = nullptr;
 }
 
 }
diff --git a/libutils/include/utils/Printer.h b/libutils/include/utils/Printer.h
index a6f6928..7465927 100644
--- a/libutils/include/utils/Printer.h
+++ b/libutils/include/utils/Printer.h
@@ -45,7 +45,7 @@
     // (Note that the default ALOG behavior is to ignore blank lines)
     LogPrinter(const char* logtag,
                android_LogPriority priority = ANDROID_LOG_DEBUG,
-               const char* prefix = 0,
+               const char* prefix = nullptr,
                bool ignoreBlankLines = false);
 
     // Print the specified line to logcat. No \n at the end is necessary.
@@ -66,7 +66,7 @@
     // Create a printer using the specified file descriptor.
     // - Each line will be prefixed with 'indent' number of blank spaces.
     // - In addition, each line will be prefixed with the 'prefix' string.
-    FdPrinter(int fd, unsigned int indent = 0, const char* prefix = 0);
+    FdPrinter(int fd, unsigned int indent = 0, const char* prefix = nullptr);
 
     // Print the specified line to the file descriptor. \n is appended automatically.
     virtual void printLine(const char* string);
@@ -90,7 +90,7 @@
     // Create a printer using the specified String8 as the target.
     // - In addition, each line will be prefixed with the 'prefix' string.
     // - target's memory lifetime must be a superset of this String8Printer.
-    String8Printer(String8* target, const char* prefix = 0);
+    String8Printer(String8* target, const char* prefix = nullptr);
 
     // Append the specified line to the String8. \n is appended automatically.
     virtual void printLine(const char* string);
diff --git a/libutils/include/utils/ProcessCallStack.h b/libutils/include/utils/ProcessCallStack.h
index b5f2edc..7e06086 100644
--- a/libutils/include/utils/ProcessCallStack.h
+++ b/libutils/include/utils/ProcessCallStack.h
@@ -43,13 +43,13 @@
 
     // Print all stack traces to the log using the supplied logtag.
     void log(const char* logtag, android_LogPriority priority = ANDROID_LOG_DEBUG,
-             const char* prefix = 0) const;
+             const char* prefix = nullptr) const;
 
     // Dump all stack traces to the specified file descriptor.
-    void dump(int fd, int indent = 0, const char* prefix = 0) const;
+    void dump(int fd, int indent = 0, const char* prefix = nullptr) const;
 
     // Return a string (possibly very long) containing all the stack traces.
-    String8 toString(const char* prefix = 0) const;
+    String8 toString(const char* prefix = nullptr) const;
 
     // Dump a serialized representation of all the stack traces to the specified printer.
     void print(Printer& printer) const;
diff --git a/libutils/include/utils/RefBase.h b/libutils/include/utils/RefBase.h
index 13b6a2b..1780cf2 100644
--- a/libutils/include/utils/RefBase.h
+++ b/libutils/include/utils/RefBase.h
@@ -563,7 +563,7 @@
 wp<T>& wp<T>::operator = (const sp<U>& other)
 {
     weakref_type* newRefs =
-        other != NULL ? other->createWeak(this) : 0;
+        other != nullptr ? other->createWeak(this) : 0;
     U* otherPtr(other.m_ptr);
     if (m_ptr) m_refs->decWeak(this);
     m_ptr = otherPtr;
diff --git a/libutils/misc.cpp b/libutils/misc.cpp
index f074341..f77e189 100644
--- a/libutils/misc.cpp
+++ b/libutils/misc.cpp
@@ -41,13 +41,13 @@
 
 #if !defined(_WIN32)
 static pthread_mutex_t gSyspropMutex = PTHREAD_MUTEX_INITIALIZER;
-static Vector<sysprop_change_callback_info>* gSyspropList = NULL;
+static Vector<sysprop_change_callback_info>* gSyspropList = nullptr;
 #endif
 
 #if !defined(_WIN32)
 void add_sysprop_change_callback(sysprop_change_callback cb, int priority) {
     pthread_mutex_lock(&gSyspropMutex);
-    if (gSyspropList == NULL) {
+    if (gSyspropList == nullptr) {
         gSyspropList = new Vector<sysprop_change_callback_info>();
     }
     sysprop_change_callback_info info;
@@ -103,7 +103,7 @@
 #if !defined(_WIN32)
     pthread_mutex_lock(&gSyspropMutex);
     Vector<sysprop_change_callback_info> listeners;
-    if (gSyspropList != NULL) {
+    if (gSyspropList != nullptr) {
         listeners = *gSyspropList;
     }
     pthread_mutex_unlock(&gSyspropMutex);
diff --git a/libutils/tests/Looper_test.cpp b/libutils/tests/Looper_test.cpp
index 8ebcfaf..2282ced 100644
--- a/libutils/tests/Looper_test.cpp
+++ b/libutils/tests/Looper_test.cpp
@@ -339,7 +339,7 @@
     Pipe pipe;
 
     pipe.writeSignal();
-    mLooper->addFd(pipe.receiveFd, expectedIdent, Looper::EVENT_INPUT, NULL, expectedData);
+    mLooper->addFd(pipe.receiveFd, expectedIdent, Looper::EVENT_INPUT, nullptr, expectedData);
 
     StopWatch stopWatch("pollOnce");
     int fd;
@@ -364,7 +364,7 @@
 
 TEST_F(LooperTest, AddFd_WhenCallbackAdded_ReturnsOne) {
     Pipe pipe;
-    int result = mLooper->addFd(pipe.receiveFd, 0, Looper::EVENT_INPUT, NULL, NULL);
+    int result = mLooper->addFd(pipe.receiveFd, 0, Looper::EVENT_INPUT, nullptr, nullptr);
 
     EXPECT_EQ(1, result)
             << "addFd should return 1 because FD was added";
@@ -372,7 +372,7 @@
 
 TEST_F(LooperTest, AddFd_WhenIdentIsNegativeAndCallbackIsNull_ReturnsError) {
     Pipe pipe;
-    int result = mLooper->addFd(pipe.receiveFd, -1, Looper::EVENT_INPUT, NULL, NULL);
+    int result = mLooper->addFd(pipe.receiveFd, -1, Looper::EVENT_INPUT, nullptr, nullptr);
 
     EXPECT_EQ(-1, result)
             << "addFd should return -1 because arguments were invalid";
@@ -381,7 +381,7 @@
 TEST_F(LooperTest, AddFd_WhenNoCallbackAndAllowNonCallbacksIsFalse_ReturnsError) {
     Pipe pipe;
     sp<Looper> looper = new Looper(false /*allowNonCallbacks*/);
-    int result = looper->addFd(pipe.receiveFd, 0, 0, NULL, NULL);
+    int result = looper->addFd(pipe.receiveFd, 0, 0, nullptr, nullptr);
 
     EXPECT_EQ(-1, result)
             << "addFd should return -1 because arguments were invalid";
diff --git a/libutils/tests/LruCache_test.cpp b/libutils/tests/LruCache_test.cpp
index 4e885bb..c4d917b 100644
--- a/libutils/tests/LruCache_test.cpp
+++ b/libutils/tests/LruCache_test.cpp
@@ -110,7 +110,7 @@
 
 class EntryRemovedCallback : public OnEntryRemoved<SimpleKey, StringValue> {
 public:
-    EntryRemovedCallback() : callbackCount(0), lastKey(-1), lastValue(NULL) { }
+    EntryRemovedCallback() : callbackCount(0), lastKey(-1), lastValue(nullptr) { }
     ~EntryRemovedCallback() {}
     void operator()(SimpleKey& k, StringValue& v) {
         callbackCount += 1;
@@ -153,7 +153,7 @@
 TEST_F(LruCacheTest, Empty) {
     LruCache<SimpleKey, StringValue> cache(100);
 
-    EXPECT_EQ(NULL, cache.get(0));
+    EXPECT_EQ(nullptr, cache.get(0));
     EXPECT_EQ(0u, cache.size());
 }
 
@@ -175,7 +175,7 @@
     cache.put(1, "one");
     cache.put(2, "two");
     cache.put(3, "three");
-    EXPECT_EQ(NULL, cache.get(1));
+    EXPECT_EQ(nullptr, cache.get(1));
     EXPECT_STREQ("two", cache.get(2));
     EXPECT_STREQ("three", cache.get(3));
     EXPECT_EQ(2u, cache.size());
@@ -188,7 +188,7 @@
     cache.put(2, "two");
     cache.put(3, "three");
     cache.removeOldest();
-    EXPECT_EQ(NULL, cache.get(1));
+    EXPECT_EQ(nullptr, cache.get(1));
     EXPECT_STREQ("two", cache.get(2));
     EXPECT_STREQ("three", cache.get(3));
     EXPECT_EQ(2u, cache.size());
@@ -203,7 +203,7 @@
     EXPECT_STREQ("one", cache.get(1));
     cache.removeOldest();
     EXPECT_STREQ("one", cache.get(1));
-    EXPECT_EQ(NULL, cache.get(2));
+    EXPECT_EQ(nullptr, cache.get(2));
     EXPECT_STREQ("three", cache.get(3));
     EXPECT_EQ(2u, cache.size());
 }
@@ -230,7 +230,7 @@
         int index = random() % kNumKeys;
         uint32_t key = hash_int(index);
         const char *val = cache.get(key);
-        if (val != NULL) {
+        if (val != nullptr) {
             EXPECT_EQ(strings[index], val);
             hitCount++;
         } else {
diff --git a/libutils/tests/Vector_test.cpp b/libutils/tests/Vector_test.cpp
index e074a92..5336c40 100644
--- a/libutils/tests/Vector_test.cpp
+++ b/libutils/tests/Vector_test.cpp
@@ -98,7 +98,7 @@
 
   // Checks that the size calculation (not the capacity calculation) doesn't
   // overflow : the size here will be (1 + SIZE_MAX).
-  EXPECT_DEATH(vector.insertArrayAt(NULL, 0, SIZE_MAX), "new_size overflow");
+  EXPECT_DEATH(vector.insertArrayAt(nullptr, 0, SIZE_MAX), "new_size overflow");
 }
 
 TEST_F(VectorTest, _grow_OverflowCapacityDoubling) {
@@ -106,14 +106,14 @@
 
   // This should fail because the calculated capacity will overflow even though
   // the size of the vector doesn't.
-  EXPECT_DEATH(vector.insertArrayAt(NULL, 0, (SIZE_MAX - 1)), "new_capacity overflow");
+  EXPECT_DEATH(vector.insertArrayAt(nullptr, 0, (SIZE_MAX - 1)), "new_capacity overflow");
 }
 
 TEST_F(VectorTest, _grow_OverflowBufferAlloc) {
   Vector<int> vector;
   // This should fail because the capacity * sizeof(int) overflows, even
   // though the capacity itself doesn't.
-  EXPECT_DEATH(vector.insertArrayAt(NULL, 0, (SIZE_MAX / 2)), "new_alloc_size overflow");
+  EXPECT_DEATH(vector.insertArrayAt(nullptr, 0, (SIZE_MAX / 2)), "new_alloc_size overflow");
 }
 
 TEST_F(VectorTest, editArray_Shared) {