67 lines
1.7 KiB
C++
67 lines
1.7 KiB
C++
/* xdelta3 - delta compression tools and library -*- Mode: C++ -*-
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Copyright 2016 Joshua MacDonald
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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static size_t CmpDifferentBlockBytes(const Block &a, const Block &b) {
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size_t total = 0;
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size_t i = 0;
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size_t m = min(a.Size(), b.Size());
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for (; i < m; i++) {
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if (a[i] != b[i]) {
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total++;
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}
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}
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total += a.Size() - i;
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total += b.Size() - i;
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return total;
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}
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static xoff_t CmpDifferentBytes(const FileSpec &a, const FileSpec &b) {
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Block block_a, block_b;
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xoff_t total = 0;
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typename FileSpec::iterator a_i(a), b_i(b);
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for (; !a_i.Done() && !b_i.Done(); a_i.Next(), b_i.Next()) {
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a_i.Get(&block_a);
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b_i.Get(&block_b);
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total += CmpDifferentBlockBytes(block_a, block_b);
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}
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for (; !a_i.Done(); a_i.Next()) {
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total += a_i.BytesOnBlock();
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}
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for (; !b_i.Done(); b_i.Next()) {
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total += b_i.BytesOnBlock();
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}
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return total;
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}
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static size_t CmpDifferentBlockBytesAtOffset(const Block &a,
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const FileSpec &b_spec,
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xoff_t offset) {
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Block b;
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size_t size = a.Size();
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CHECK_LE(offset, b_spec.Size());
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if (b_spec.Size() < offset + size) {
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size = b_spec.Size() - offset;
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}
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b_spec.Get(&b, offset, size);
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return CmpDifferentBlockBytes(a, b);
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}
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