[Courgette] Refactor BSDiff namespaces and bsdiff::search() interface.

courgette/third_party/bsdiff/bsdiff_create.cc

-/*
-  bsdiff.c -- Binary patch generator.
+// Copyright 2003, 2004 Colin Percival
+// All rights reserved
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted providing that the following conditions
+// are met:
+// 1. Redistributions of source code must retain the above copyright
+//    notice, this list of conditions and the following disclaimer.
+// 2. Redistributions in binary form must reproduce the above copyright
+//    notice, this list of conditions and the following disclaimer in the
+//    documentation and/or other materials provided with the distribution.
+//
+// For the terms under which this work may be distributed, please see
+// the adjoining file "LICENSE".
+//
+// bsdiff_create.c -- Binary patch generator.
+//
+// ChangeLog:
+// 2005-05-05 - Use the modified header struct from bspatch.h; use 32-bit
+//              values throughout.
+//                --Benjamin Smedberg <benjamin@smedbergs.us>
+// 2005-05-18 - Use the same CRC algorithm as bzip2, and leverage the CRC table
+//              provided by libbz2.
+//                --Darin Fisher <darin@meer.net>
+// 2007-11-14 - Changed to use Crc from Lzma library instead of Bzip library
+//                --Rahul Kuchhal
+// 2009-03-31 - Change to use Streams.  Added lots of comments.
+//                --Stephen Adams <sra@chromium.org>
+// 2010-05-26 - Use a paged array for V and I. The address space may be too
+//              fragmented for these big arrays to be contiguous.
+//               --Stephen Adams <sra@chromium.org>
+// 2015-08-03 - Extract qsufsort portion to a separate file.
+//                --Samuel Huang <huangs@chromium.org>
+// 2015-08-12 - Interface change to search().
+//                --Samuel Huang <huangs@chromium.org>
 
-  Copyright 2003 Colin Percival
-
-  For the terms under which this work may be distributed, please see
-  the adjoining file "LICENSE".
-
-  ChangeLog:
-  2005-05-05 - Use the modified header struct from bspatch.h; use 32-bit
-               values throughout.
-                 --Benjamin Smedberg <benjamin@smedbergs.us>
-  2005-05-18 - Use the same CRC algorithm as bzip2, and leverage the CRC table
-               provided by libbz2.
-                 --Darin Fisher <darin@meer.net>
-  2007-11-14 - Changed to use Crc from Lzma library instead of Bzip library
-                 --Rahul Kuchhal
-  2009-03-31 - Change to use Streams.  Added lots of comments.
-                 --Stephen Adams <sra@chromium.org>
-  2010-05-26 - Use a paged array for V and I. The address space may be too
-               fragmented for these big arrays to be contiguous.
-                 --Stephen Adams <sra@chromium.org>
-  2015-08-03 - Extract qsufsort portion to a separate file.
-                 --Samuel Huang <huangs@chromium.org>
-  2015-08-12 - Interface change to qsufsort search().
-                 --Samuel Huang <huangs@chromium.org>
-*/
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
 
 #include "courgette/third_party/bsdiff/bsdiff.h"
 
 #include <stddef.h>
 #include <stdint.h>
 #include <stdlib.h>
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/strings/string_util.h"
 #include "base/time/time.h"
 
 #include "courgette/crc.h"
 #include "courgette/streams.h"
+#include "courgette/third_party/bsdiff/bsdiff_search.h"
 #include "courgette/third_party/bsdiff/paged_array.h"
 #include "courgette/third_party/bsdiff/qsufsort.h"
 
-namespace courgette {
+namespace {
+
+using courgette::CalculateCrc;
+using courgette::PagedArray;
+using courgette::SinkStream;
+using courgette::SinkStreamSet;
+using courgette::SourceStream;
+using courgette::SourceStreamSet;
+
+}  // namespace
+
+namespace bsdiff {
 
 static CheckBool WriteHeader(SinkStream* stream, MBSPatchHeader* header) {
   bool ok = stream->Write(header->tag, sizeof(header->tag));
   ok &= stream->WriteVarint32(header->slen);
   ok &= stream->WriteVarint32(header->scrc32);
   ok &= stream->WriteVarint32(header->dlen);
   return ok;
 }
 
 BSDiffStatus CreateBinaryPatch(SourceStream* old_stream,
@@ skipping 88 matching lines @@
   int scan = 0;
   int match_length = 0;
 
   while (scan < newsize) {
     int pos = 0;
     int oldscore = 0;  // Count of how many bytes of the current match at |scan|
                        // extend the match at |lastscan|.
 
     scan += match_length;
     for (int scsc = scan; scan < newsize; ++scan) {
-      match_length = qsuf::search<PagedArray<int>&>(
+      match_length = search<PagedArray<int>&>(
           I, old, oldsize, newbuf + scan, newsize - scan, &pos);
 
       for (; scsc < scan + match_length; scsc++)
         if ((scsc + lastoffset < oldsize) &&
             (old[scsc + lastoffset] == newbuf[scsc]))
           oldscore++;
 
       if ((match_length == oldscore) && (match_length != 0))
         break;  // Good continuing match, case (1)
       if (match_length > oldscore + 8)
@@ skipping 144 matching lines @@
           << "  (skips: " << diff_skips_length << ")"
           << "  extra bytes: " << extra_bytes_length
           << "\nUncompressed bsdiff patch size "
           << patch_stream->Length() - initial_patch_stream_length
           << "\nEnd bsdiff "
           << (base::Time::Now() - start_bsdiff_time).InSecondsF();
 
   return OK;
 }
 
-}  // namespace courgette
+}  // namespace bsdiff