1 files changed, 21 insertions, 20 deletions

diff --git a/re2/testing/string_generator.cc b/re2/testing/string_generator.cc
index 5be6d3e..feef200 100644
--- a/re2/testing/string_generator.cc
+++ b/re2/testing/string_generator.cc
@@ -6,30 +6,31 @@
 // maxlen letters using the set of letters in alpha.
 // Fetch strings using a Java-like Next()/HasNext() interface.
 
+#include <stddef.h>
+#include <stdint.h>
 #include <string>
 #include <vector>
+
 #include "util/test.h"
+#include "util/logging.h"
 #include "re2/testing/string_generator.h"
 
 namespace re2 {
 
-StringGenerator::StringGenerator(int maxlen, const vector<string>& alphabet)
+StringGenerator::StringGenerator(int maxlen,
+                                 const std::vector<string>& alphabet)
     : maxlen_(maxlen), alphabet_(alphabet),
       generate_null_(false),
-      random_(false), nrandom_(0), acm_(NULL) {
+      random_(false), nrandom_(0) {
 
   // Degenerate case: no letters, no non-empty strings.
-  if (alphabet_.size() == 0)
+  if (alphabet_.empty())
     maxlen_ = 0;
 
   // Next() will return empty string (digits_ is empty).
   hasnext_ = true;
 }
 
-StringGenerator::~StringGenerator() {
-  delete acm_;
-}
-
 // Resets the string generator state to the beginning.
 void StringGenerator::Reset() {
   digits_.clear();
@@ -43,14 +44,14 @@ void StringGenerator::Reset() {
 // Returns false if all the numbers have been used.
 bool StringGenerator::IncrementDigits() {
   // First try to increment the current number.
-  for (int i = digits_.size() - 1; i >= 0; i--) {
-    if (++digits_[i] < alphabet_.size())
+  for (int i = static_cast<int>(digits_.size()) - 1; i >= 0; i--) {
+    if (++digits_[i] < static_cast<int>(alphabet_.size()))
       return true;
     digits_[i] = 0;
   }
 
   // If that failed, make a longer number.
-  if (digits_.size() < maxlen_) {
+  if (static_cast<int>(digits_.size()) < maxlen_) {
     digits_.push_back(0);
     return true;
   }
@@ -64,11 +65,15 @@ bool StringGenerator::RandomDigits() {
   if (--nrandom_ <= 0)
     return false;
 
+  std::uniform_int_distribution<int> random_len(0, maxlen_);
+  std::uniform_int_distribution<int> random_alphabet_index(
+      0, static_cast<int>(alphabet_.size()) - 1);
+
   // Pick length.
-  int len = acm_->Uniform(maxlen_+1);
+  int len = random_len(rng_);
   digits_.resize(len);
   for (int i = 0; i < len; i++)
-    digits_[i] = acm_->Uniform(alphabet_.size());
+    digits_[i] = random_alphabet_index(rng_);
   return true;
 }
 
@@ -80,11 +85,11 @@ const StringPiece& StringGenerator::Next() {
   CHECK(hasnext_);
   if (generate_null_) {
     generate_null_ = false;
-    sp_ = NULL;
+    sp_ = StringPiece();
     return sp_;
   }
   s_.clear();
-  for (int i = 0; i < digits_.size(); i++) {
+  for (size_t i = 0; i < digits_.size(); i++) {
     s_ += alphabet_[digits_[i]];
   }
   hasnext_ = random_ ? RandomDigits() : IncrementDigits();
@@ -93,11 +98,8 @@ const StringPiece& StringGenerator::Next() {
 }
 
 // Sets generator up to return n random strings.
-void StringGenerator::Random(int32 seed, int n) {
-  if (acm_ == NULL)
-    acm_ = new ACMRandom(seed);
-  else
-    acm_->Reset(seed);
+void StringGenerator::Random(int32_t seed, int n) {
+  rng_.seed(seed);
 
   random_ = true;
   nrandom_ = n;
@@ -110,4 +112,3 @@ void StringGenerator::GenerateNULL() {
 }
 
 }  // namespace re2
-