+
+ BlockList blocks_to_reserve;
+ for(BlockIter b=block; b; b=b.next())
+ {
+ if(b->get_train())
+ break;
+ blocks_to_reserve.push_back(b);
+ for(TrackIter t=b.track_iter(); (t && &t->get_block()==&*b); t=t.next())
+ remaining_length -= t->get_path_length();
+ if(remaining_length<=0)
+ break;
+ }
+
+ if(remaining_length>0)
+ return false;
+
+ for(BlockList::iterator i=blocks_to_reserve.begin(); i!=blocks_to_reserve.end(); ++i)
+ {
+ blocks.push_back(*i);
+ try
+ {
+ (*i)->reserve(&train);
+ }
+ catch(...)
+ {
+ blocks.pop_back();
+ while(i!=blocks_to_reserve.begin())
+ {
+ blocks.pop_back();
+ (*--i)->reserve(0);
+ }
+ throw;
+ }
+ }
+
+ return true;