Added Brotli compress/decompress utilities and makefiles
diff --git a/brotli/enc/encode.cc b/brotli/enc/encode.cc
index bb3e3b8..88e1c4c 100644
--- a/brotli/enc/encode.cc
+++ b/brotli/enc/encode.cc
@@ -34,6 +34,18 @@
namespace brotli {
+static const int kWindowBits = 22;
+// To make decoding faster, we allow the decoder to write 16 bytes ahead in
+// its ringbuffer, therefore the encoder has to decrease max distance by this
+// amount.
+static const int kDecoderRingBufferWriteAheadSlack = 16;
+static const int kMaxBackwardDistance =
+ (1 << kWindowBits) - kDecoderRingBufferWriteAheadSlack;
+
+static const int kMetaBlockSizeBits = 21;
+static const int kRingBufferBits = 23;
+static const int kRingBufferMask = (1 << kRingBufferBits) - 1;
+
template<int kSize>
double Entropy(const std::vector<Histogram<kSize> >& histograms) {
double retval = 0;
@@ -264,7 +276,7 @@
uint64_t insert_extra_bits_val =
cmd.insert_length_ - InsertLengthOffset(code);
int copy_extra_bits = CopyLengthExtraBits(code);
- uint64_t copy_extra_bits_val = cmd.copy_length_ - CopyLengthOffset(code);
+ uint64_t copy_extra_bits_val = cmd.copy_length_code_ - CopyLengthOffset(code);
if (insert_extra_bits > 0) {
WriteBits(insert_extra_bits, insert_extra_bits_val, storage_ix, storage);
}
@@ -325,8 +337,8 @@
for (int i = 0; i < cmds->size(); ++i) {
Command* cmd = &(*cmds)[i];
cmd->command_prefix_ = CommandPrefix(cmd->insert_length_,
- cmd->copy_length_);
- if (cmd->copy_length_ > 0) {
+ cmd->copy_length_code_);
+ if (cmd->copy_length_code_ > 0) {
PrefixEncodeCopyDistance(cmd->distance_code_,
num_direct_distance_codes,
distance_postfix_bits,
@@ -454,7 +466,7 @@
int* storage_ix, uint8_t* storage) {
WriteBits(8, num_clusters - 1, storage_ix, storage);
- if (num_clusters == 1 || num_clusters == context_map.size()) {
+ if (num_clusters == 1) {
return;
}
@@ -737,10 +749,10 @@
}
if (*pos < end_pos && cmd.distance_prefix_ != 0xffff) {
MoveAndEncode(distance_split_code, &distance_it, storage_ix, storage);
- int histogram_index = distance_it.type_;
int context = (distance_it.type_ << 2) +
- ((cmd.copy_length_ > 4) ? 3 : cmd.copy_length_ - 2);
- histogram_index = mb.distance_context_map[context];
+ ((cmd.copy_length_code_ > 4) ? 3 : cmd.copy_length_code_ - 2);
+ int histogram_index = mb.distance_context_map[context];
+ size_t max_distance = std::min(*pos, (size_t)kMaxBackwardDistance);
EncodeCopyDistance(cmd, distance_codes[histogram_index],
storage_ix, storage);
}
@@ -748,32 +760,21 @@
}
}
-static const int kWindowBits = 22;
-// To make decoding faster, we allow the decoder to write 16 bytes ahead in
-// its ringbuffer, therefore the encoder has to decrease max distance by this
-// amount.
-static const int kDecoderRingBufferWriteAheadSlack = 16;
-static const int kMaxBackwardDistance =
- (1 << kWindowBits) - kDecoderRingBufferWriteAheadSlack;
-
-static const int kMetaBlockSizeBits = 21;
-static const int kRingBufferBits = 23;
-static const int kRingBufferMask = (1 << kRingBufferBits) - 1;
-
BrotliCompressor::BrotliCompressor()
- : hasher_(new Hasher),
+ : window_bits_(kWindowBits),
+ hasher_(new Hasher),
dist_ringbuffer_idx_(0),
input_pos_(0),
ringbuffer_(kRingBufferBits, kMetaBlockSizeBits),
literal_cost_(1 << kRingBufferBits),
storage_ix_(0),
storage_(new uint8_t[2 << kMetaBlockSizeBits]) {
- dist_ringbuffer_[0] = 4;
- dist_ringbuffer_[1] = 11;
- dist_ringbuffer_[2] = 15;
- dist_ringbuffer_[3] = 16;
- storage_[0] = 0;
- }
+ dist_ringbuffer_[0] = 4;
+ dist_ringbuffer_[1] = 11;
+ dist_ringbuffer_[2] = 15;
+ dist_ringbuffer_[3] = 16;
+ storage_[0] = 0;
+}
BrotliCompressor::~BrotliCompressor() {
delete hasher_;
@@ -784,8 +785,12 @@
// Don't encode input size.
WriteBits(3, 0, &storage_ix_, storage_);
// Encode window size.
- WriteBits(1, 1, &storage_ix_, storage_);
- WriteBits(3, kWindowBits - 17, &storage_ix_, storage_);
+ if (window_bits_ == 16) {
+ WriteBits(1, 0, &storage_ix_, storage_);
+ } else {
+ WriteBits(1, 1, &storage_ix_, storage_);
+ WriteBits(3, window_bits_ - 17, &storage_ix_, storage_);
+ }
}
void BrotliCompressor::WriteMetaBlock(const size_t input_size,