0ad/source/lib/res/file/tests/test_file_cache.h

#include "lib/self_test.h"

#include "lib/res/file/file_cache.h"
#include "lib/rand.h"

class TestFileCache : public CxxTest::TestSuite 
{
	enum { TEST_ALLOC_TOTAL = 100*1000*1000 };
public:
	void test_cache_allocator()
	{
		// allocated address -> its size
		typedef std::map<void*, size_t> AllocMap;
		AllocMap allocations;

		// put allocator through its paces by allocating several times
		// its capacity (this ensures memory is reused)
		srand(1);
		size_t total_size_used = 0;
		while(total_size_used < TEST_ALLOC_TOTAL)
		{
			size_t size = rand(1, TEST_ALLOC_TOTAL/16);
			total_size_used += size;
			void* p;
			// until successful alloc:
			for(;;)
			{
				p = file_cache_allocator_alloc(size);
				if(p)
					break;
				// out of room - remove a previous allocation
				// .. choose one at random
				size_t chosen_idx = (size_t)rand(0, (uint)allocations.size());
				AllocMap::iterator it = allocations.begin();
				for(; chosen_idx != 0; chosen_idx--)
					++it;
				file_cache_allocator_free(it->first, it->second);
				allocations.erase(it);
			}

			// must not already have been allocated
			TS_ASSERT_EQUALS(allocations.find(p), allocations.end());
			allocations[p] = size;
		}

		// reset to virginal state
		// note: even though everything has now been freed, this is
		// necessary since the freelists may be a bit scattered already.
		file_cache_allocator_reset();
	}
};