Identifying call sites that need to handle out of memory situations in Courgette.

courgette/third_party/bsdiff_apply.cc

 /*-
  * 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
@@ skipping 59 matching lines @@
   SourceStream* diff_skips = patch_streams.stream(3);
   SourceStream* diff_bytes = patch_streams.stream(4);
   SourceStream* extra_bytes = patch_streams.stream(5);
 
   const uint8* extra_start = extra_bytes->Buffer();
   const uint8* extra_end = extra_start + extra_bytes->Remaining();
   const uint8* extra_position = extra_start;
 
   const uint8* old_position = old_start;
 
-  new_stream->Reserve(header->dlen);
+  if (header->dlen && !new_stream->Reserve(header->dlen))
+    return MEM_ERROR;
 
   uint32 pending_diff_zeros = 0;
   if (!diff_skips->ReadVarint32(&pending_diff_zeros))
     return UNEXPECTED_ERROR;
 
   while (!control_stream_copy_counts->Empty()) {
     uint32 copy_count, extra_count;
     int32 seek_adjustment;
     if (!control_stream_copy_counts->ReadVarint32(&copy_count))
       return UNEXPECTED_ERROR;
@@ skipping 16 matching lines @@
       uint8 diff_byte = 0;
       if (pending_diff_zeros) {
         --pending_diff_zeros;
       } else {
         if (!diff_skips->ReadVarint32(&pending_diff_zeros))
           return UNEXPECTED_ERROR;
         if (!diff_bytes->Read(&diff_byte, 1))
           return UNEXPECTED_ERROR;
       }
       uint8 byte = old_position[i] + diff_byte;
-      new_stream->Write(&byte, 1);
+      if (!new_stream->Write(&byte, 1))
+        return MEM_ERROR;
     }
     old_position += copy_count;
 
     // Copy bytes from the extra block.
     if (extra_count > static_cast<size_t>(extra_end - extra_position))
       return UNEXPECTED_ERROR;
 
-    new_stream->Write(extra_position, extra_count);
+    if (!new_stream->Write(extra_position, extra_count))
+      return MEM_ERROR;
+
     extra_position += extra_count;
 
     // "seek" forwards (or backwards) in oldfile.
     if (old_position + seek_adjustment < old_start ||
         old_position + seek_adjustment > old_end)
       return UNEXPECTED_ERROR;
 
     old_position += seek_adjustment;
   }
 
@@ skipping 22 matching lines @@
 
   if (CalculateCrc(old_start, old_size) != header.scrc32)
     return CRC_ERROR;
 
   MBS_ApplyPatch(&header, patch_stream, old_start, old_size, new_stream);
 
   return OK;
 }
 
 }  // namespace