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diff --git a/sdch/open-vcdiff/src/varint_bigendian.cc b/sdch/open-vcdiff/src/varint_bigendian.cc
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+// Copyright 2008 Google Inc.
+// Author: Lincoln Smith
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include <config.h>
+#include "varint_bigendian.h"
+#include <stdint.h> // int32_t, int64_t
+#include <string.h> // memcpy
+#include <string>
+#include "logging.h"
+#include "google/output_string.h"
+
+namespace open_vcdiff {
+
+template<> const int32_t VarintBE<int32_t>::kMaxVal = 0x7FFFFFFF;
+template<> const int64_t VarintBE<int64_t>::kMaxVal = 0x7FFFFFFFFFFFFFFFULL;
+
+// Reads a variable-length integer from **varint_ptr
+// and returns it in a fixed-length representation. Increments
+// *varint_ptr by the number of bytes read. Will not read
+// past limit. Returns RESULT_ERROR if the value parsed
+// does not fit in a non-negative signed integer, or if limit is NULL.
+// Returns RESULT_END_OF_DATA if address_stream_end is reached
+// before the whole integer can be decoded.
+//
+template <typename SignedIntegerType>
+SignedIntegerType VarintBE<SignedIntegerType>::Parse(const char* limit,
+ const char** varint_ptr) {
+ if (!limit) {
+ return RESULT_ERROR;
+ }
+ SignedIntegerType result = 0;
+ for (const char* parse_ptr = *varint_ptr; parse_ptr < limit; ++parse_ptr) {
+ result += *parse_ptr & 0x7F;
+ if (!(*parse_ptr & 0x80)) {
+ *varint_ptr = parse_ptr + 1;
+ return result;
+ }
+ if (result > (kMaxVal >> 7)) {
+ // Shifting result by 7 bits would produce a number too large
+ // to be stored in a non-negative SignedIntegerType (an overflow.)
+ return RESULT_ERROR;
+ }
+ result = result << 7;
+ }
+ return RESULT_END_OF_DATA;
+}
+
+template <typename SignedIntegerType>
+int VarintBE<SignedIntegerType>::EncodeInternal(SignedIntegerType v,
+ char* varint_buf) {
+ if (v < 0) {
+ LOG(DFATAL) << "Negative value " << v
+ << " passed to VarintBE::EncodeInternal,"
+ " which requires non-negative argument" << LOG_ENDL;
+ return 0;
+ }
+ int length = 1;
+ char* buf_ptr = &varint_buf[kMaxBytes - 1];
+ *buf_ptr = static_cast<char>(v & 0x7F);
+ --buf_ptr;
+ v >>= 7;
+ while (v) {
+ *buf_ptr = static_cast<char>((v & 0x7F) | 0x80); // add continuation bit
+ --buf_ptr;
+ ++length;
+ v >>= 7;
+ }
+ return length;
+}
+
+template <typename SignedIntegerType>
+int VarintBE<SignedIntegerType>::Encode(SignedIntegerType v, char* ptr) {
+ char varint_buf[kMaxBytes];
+ const int length = EncodeInternal(v, varint_buf);
+ memcpy(ptr, &varint_buf[kMaxBytes - length], length);
+ return length;
+}
+
+template <typename SignedIntegerType>
+void VarintBE<SignedIntegerType>::AppendToString(SignedIntegerType value,
+ string* s) {
+ char varint_buf[kMaxBytes];
+ const int length = EncodeInternal(value, varint_buf);
+ s->append(&varint_buf[kMaxBytes - length], length);
+}
+
+template <typename SignedIntegerType>
+void VarintBE<SignedIntegerType>::AppendToOutputString(
+ SignedIntegerType value,
+ OutputStringInterface* output_string) {
+ char varint_buf[kMaxBytes];
+ const int length = EncodeInternal(value, varint_buf);
+ output_string->append(&varint_buf[kMaxBytes - length], length);
+}
+
+// Returns the encoding length of the specified value.
+template <typename SignedIntegerType>
+int VarintBE<SignedIntegerType>::Length(SignedIntegerType v) {
+ if (v < 0) {
+ LOG(DFATAL) << "Negative value " << v
+ << " passed to VarintBE::Length,"
+ " which requires non-negative argument" << LOG_ENDL;
+ return 0;
+ }
+ int length = 0;
+ do {
+ v >>= 7;
+ ++length;
+ } while (v);
+ return length;
+}
+
+template class VarintBE<int32_t>;
+template class VarintBE<int64_t>;
+
+} // namespace open_vcdiff