diff --git a/cmds/dumpstate/DumpstateUtil.cpp b/cmds/dumpstate/DumpstateUtil.cpp
index 85eb464..600a500 100644
--- a/cmds/dumpstate/DumpstateUtil.cpp
+++ b/cmds/dumpstate/DumpstateUtil.cpp
@@ -56,11 +56,11 @@
     timespec ts;
     ts.tv_sec = MSEC_TO_SEC(timeout_ms);
     ts.tv_nsec = (timeout_ms % 1000) * 1000000;
-    int ret = TEMP_FAILURE_RETRY(sigtimedwait(&child_mask, NULL, &ts));
+    int ret = TEMP_FAILURE_RETRY(sigtimedwait(&child_mask, nullptr, &ts));
     int saved_errno = errno;
 
     // Set the signals back the way they were.
-    if (sigprocmask(SIG_SETMASK, &old_mask, NULL) == -1) {
+    if (sigprocmask(SIG_SETMASK, &old_mask, nullptr) == -1) {
         printf("*** sigprocmask failed: %s\n", strerror(errno));
         if (ret == 0) {
             return false;
@@ -310,7 +310,7 @@
         struct sigaction sigact;
         memset(&sigact, 0, sizeof(sigact));
         sigact.sa_handler = SIG_IGN;
-        sigaction(SIGPIPE, &sigact, NULL);
+        sigaction(SIGPIPE, &sigact, nullptr);
 
         execvp(path, (char**)args.data());
         // execvp's result will be handled after waitpid_with_timeout() below, but
diff --git a/cmds/dumpstate/dumpstate.cpp b/cmds/dumpstate/dumpstate.cpp
index dec767d..2c248c6 100644
--- a/cmds/dumpstate/dumpstate.cpp
+++ b/cmds/dumpstate/dumpstate.cpp
@@ -90,7 +90,7 @@
 
 /* read before root is shed */
 static char cmdline_buf[16384] = "(unknown)";
-static const char *dump_traces_path = NULL;
+static const char *dump_traces_path = nullptr;
 
 // TODO: variables and functions below should be part of dumpstate object
 
@@ -295,7 +295,7 @@
     char path[PATH_MAX];
 
     d = opendir(driverpath);
-    if (d == NULL) {
+    if (d == nullptr) {
         return;
     }
 
@@ -587,7 +587,7 @@
 static int dump_stat_from_fd(const char *title __unused, const char *path, int fd) {
     unsigned long long fields[__STAT_NUMBER_FIELD];
     bool z;
-    char *cp, *buffer = NULL;
+    char *cp, *buffer = nullptr;
     size_t i = 0;
     FILE *fp = fdopen(dup(fd), "rb");
     getline(&buffer, &i, fp);
@@ -1686,7 +1686,7 @@
             | O_CLOEXEC | O_NOFOLLOW)));
     if (fd == -1) {
         MYLOGE("open(%s): %s\n", filepath.c_str(), strerror(errno));
-        return NULL;
+        return nullptr;
     }
 
     SHA256_CTX ctx;
@@ -1699,7 +1699,7 @@
             break;
         } else if (bytes_read == -1) {
             MYLOGE("read(%s): %s\n", filepath.c_str(), strerror(errno));
-            return NULL;
+            return nullptr;
         }
 
         SHA256_Update(&ctx, buffer.data(), bytes_read);
@@ -1748,7 +1748,7 @@
     int do_add_date = 0;
     int do_zip_file = 0;
     int do_vibrate = 1;
-    char* use_outfile = 0;
+    char* use_outfile = nullptr;
     int use_socket = 0;
     int use_control_socket = 0;
     int do_fb = 0;
diff --git a/cmds/dumpstate/utils.cpp b/cmds/dumpstate/utils.cpp
index 9beff98..77f09b7 100644
--- a/cmds/dumpstate/utils.cpp
+++ b/cmds/dumpstate/utils.cpp
@@ -525,13 +525,13 @@
     if (PropertiesHelper::IsDryRun()) return;
 
     /* Get size of kernel buffer */
-    int size = klogctl(KLOG_SIZE_BUFFER, NULL, 0);
+    int size = klogctl(KLOG_SIZE_BUFFER, nullptr, 0);
     if (size <= 0) {
         printf("Unexpected klogctl return value: %d\n\n", size);
         return;
     }
     char *buf = (char *) malloc(size + 1);
-    if (buf == NULL) {
+    if (buf == nullptr) {
         printf("memory allocation failed\n\n");
         return;
     }
@@ -598,7 +598,7 @@
     DurationReporter duration_reporter(title);
     DIR *dirp;
     struct dirent *d;
-    char *newpath = NULL;
+    char *newpath = nullptr;
     const char *slash = "/";
     int retval = 0;
 
@@ -611,7 +611,7 @@
         ++slash;
     }
     dirp = opendir(dir);
-    if (dirp == NULL) {
+    if (dirp == nullptr) {
         retval = -errno;
         MYLOGE("%s: %s\n", dir, strerror(errno));
         return retval;
@@ -620,7 +620,7 @@
     if (!dump_from_fd) {
         dump_from_fd = dump_file_from_fd;
     }
-    for (; ((d = readdir(dirp))); free(newpath), newpath = NULL) {
+    for (; ((d = readdir(dirp))); free(newpath), newpath = nullptr) {
         if ((d->d_name[0] == '.')
          && (((d->d_name[1] == '.') && (d->d_name[2] == '\0'))
           || (d->d_name[1] == '\0'))) {
@@ -648,7 +648,7 @@
             printf("*** %s: %s\n", newpath, strerror(errno));
             continue;
         }
-        (*dump_from_fd)(NULL, newpath, fd.get());
+        (*dump_from_fd)(nullptr, newpath, fd.get());
     }
     closedir(dirp);
     if (!title.empty()) {