1 files changed, 51 insertions, 0 deletions
diff --git a/modules/brotli/enc/histogram_inc.h b/modules/brotli/enc/histogram_inc.h
new file mode 100644
index 0000000000..50eaf7468d
--- /dev/null
+++ b/modules/brotli/enc/histogram_inc.h
@@ -0,0 +1,51 @@
+/* NOLINT(build/header_guard) */
+/* Copyright 2013 Google Inc. All Rights Reserved.
+
+   Distributed under MIT license.
+   See file LICENSE for detail or copy at https://opensource.org/licenses/MIT
+*/
+
+/* template parameters: Histogram, DATA_SIZE, DataType */
+
+/* A simple container for histograms of data in blocks. */
+
+typedef struct FN(Histogram) {
+  uint32_t data_[DATA_SIZE];
+  size_t total_count_;
+  double bit_cost_;
+} FN(Histogram);
+
+static BROTLI_INLINE void FN(HistogramClear)(FN(Histogram)* self) {
+  memset(self->data_, 0, sizeof(self->data_));
+  self->total_count_ = 0;
+  self->bit_cost_ = HUGE_VAL;
+}
+
+static BROTLI_INLINE void FN(ClearHistograms)(
+    FN(Histogram)* array, size_t length) {
+  size_t i;
+  for (i = 0; i < length; ++i) FN(HistogramClear)(array + i);
+}
+
+static BROTLI_INLINE void FN(HistogramAdd)(FN(Histogram)* self, size_t val) {
+  ++self->data_[val];
+  ++self->total_count_;
+}
+
+static BROTLI_INLINE void FN(HistogramAddVector)(FN(Histogram)* self,
+    const DataType* p, size_t n) {
+  self->total_count_ += n;
+  n += 1;
+  while (--n) ++self->data_[*p++];
+}
+
+static BROTLI_INLINE void FN(HistogramAddHistogram)(FN(Histogram)* self,
+    const FN(Histogram)* v) {
+  size_t i;
+  self->total_count_ += v->total_count_;
+  for (i = 0; i < DATA_SIZE; ++i) {
+    self->data_[i] += v->data_[i];
+  }
+}
+
+static BROTLI_INLINE size_t FN(HistogramDataSize)(void) { return DATA_SIZE; }