Switch out use of std::string and std::vector for large allocations for a buffer class that doesn...

courgette/ensemble_create.cc

-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
+// Copyright (c) 2011 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.
 
 // The main idea in Courgette is to do patching *under a tranformation*.  The
 // input is transformed into a new representation, patching occurs in the new
 // repesentation, and then the tranform is reversed to get the patched data.
 //
 // The idea is applied to pieces (or 'elements') of the whole (or 'ensemble').
 // Each of the elements has to go through the same set of steps in lock-step.
 
@@ skipping 214 matching lines @@
     return generators_status;
 
   SinkStreamSet patch_streams;
 
   SinkStream* tranformation_descriptions      = patch_streams.stream(0);
   SinkStream* parameter_correction            = patch_streams.stream(1);
   SinkStream* transformed_elements_correction = patch_streams.stream(2);
   SinkStream* ensemble_correction             = patch_streams.stream(3);
 
   size_t number_of_transformations = generators.size();
-  tranformation_descriptions->WriteSizeVarint32(number_of_transformations);
+  if (!tranformation_descriptions->WriteSizeVarint32(number_of_transformations))
+    return C_STREAM_ERROR;
 
   for (size_t i = 0;  i < number_of_transformations;  ++i) {
     CourgettePatchFile::TransformationMethodId kind = generators[i]->Kind();
-    tranformation_descriptions->WriteVarint32(kind);
+    if (!tranformation_descriptions->WriteVarint32(kind))
+      return C_STREAM_ERROR;
   }
 
   for (size_t i = 0;  i < number_of_transformations;  ++i) {
     Status status =
         generators[i]->WriteInitialParameters(tranformation_descriptions);
     if (status != C_OK)
       return status;
   }
 
   //
@@ skipping 143 matching lines @@
   predicted_ensemble_source.Init(predicted_ensemble);
   Status delta3_status = GenerateSimpleDelta(&predicted_ensemble_source,
                                              update,
                                              ensemble_correction);
   if (delta3_status != C_OK)
     return delta3_status;
 
   //
   // Final output stream has a header followed by a StreamSet.
   //
-  final_patch->WriteVarint32(CourgettePatchFile::kMagic);
-  final_patch->WriteVarint32(CourgettePatchFile::kVersion);
-
-  final_patch->WriteVarint32(
-      CalculateCrc(old_region.start(), old_region.length()));
-  final_patch->WriteVarint32(
-      CalculateCrc(new_region.start(), new_region.length()));
-  final_patch->WriteSizeVarint32(final_patch_input_size);
-
-  if (!patch_streams.CopyTo(final_patch))
+  if (!final_patch->WriteVarint32(CourgettePatchFile::kMagic) ||
+      !final_patch->WriteVarint32(CourgettePatchFile::kVersion) ||
+      !final_patch->WriteVarint32(CalculateCrc(old_region.start(),
+                                               old_region.length())) ||
+      !final_patch->WriteVarint32(CalculateCrc(new_region.start(),
+                                               new_region.length())) ||
+      !final_patch->WriteSizeVarint32(final_patch_input_size) ||
+      !patch_streams.CopyTo(final_patch)) {
     return C_STREAM_ERROR;
+  }
 
   VLOG(1) << "done GenerateEnsemblePatch "
           << (base::Time::Now() - start_time).InSecondsF() << "s";
 
   return C_OK;
 }
 
 }  // namespace