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* Use "/*" instead of "/**" in starting comments at the begining of a file.lloyd2010-06-071-1/+1
| | | | | This caused Doxygen to think this was markup meant for it, which really caused some clutter in the namespace page.
* Use unaligned reads/writes in xor_buf.h - bad macro name!lloyd2009-12-231-2/+2
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* Tick to 1.9.3-devlloyd2009-11-061-2/+2
| | | | | Rename BOTAN_UNALIGNED_LOADSTOR_OK to BOTAN_UNALIGNED_MEMORY_ACCESS_OK which is somewhat more clear as to the point.
* Thomas Moschny passed along a request from the Fedora packagers which camelloyd2009-03-301-0/+2
| | | | | | | | | | | | | | | up during the Fedora submission review, that each source file include some text about the license. One handy Perl script later and each file now has the line Distributed under the terms of the Botan license after the copyright notices. While I was in there modifying every file anyway, I also stripped out the remainder of the block comments (lots of astericks before and after the text); this is stylistic thing I picked up when I was first learning C++ but in retrospect it is not a good style as the structure makes it harder to modify comments (with the result that comments become fewer, shorter and are less likely to be updated, which are not good things).
* Check in a branch with a major redesign on how entropy polling is performed.lloyd2009-01-271-18/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Combine the fast and slow polls, into a single poll() operation. Instead of being given a buffer to write output into, the EntropySource is passed an Entropy_Accumulator. This handles the RLE encoding that xor_into_buf used to do. It also contains a cached I/O buffer so entropy sources do not individually need to allocate memory for that with each poll. When data is added to the accumulator, the source specifies an estimate of the number of bits of entropy per byte, as a double. This is tracked in the accumulator. Once the estimated entropy hits a target (set by the constructor), the accumulator's member function predicate polling_goal_achieved flips to true. This signals to the PRNG that it can stop performing polling on sources, also polls that take a long time periodically check this flag and return immediately. The Win32 and BeOS entropy sources have been updated, but blindly; testing is needed. The test_es example program has been modified: now it polls twice and outputs the XOR of the two collected results. That helps show if the output is consistent across polls (not a good thing). I have noticed on the Unix entropy source, occasionally there are many 0x00 bytes in the output, which is not optimal. This also needs to be investigated. The RLE is not actually RLE anymore. It works well for non-random inputs (ASCII text, etc), but I noticed that when /dev/random output was fed into it, the output buffer would end up being RR01RR01RR01 where RR is a random byte and 00 is the byte count. The buffer sizing also needs to be examined carefully. It might be useful to choose a prime number for the size to XOR stuff into, to help ensure an even distribution of entropy across the entire buffer space. Or: feed it all into a hash function? This change should (perhaps with further modifications) help WRT the concerns Zack W raised about the RNG on the monotone-dev list.
* Use a simple run length encoding in xor_into_buf, so long blocks of spaces,lloyd2008-11-231-1/+3
| | | | | zero bytes, etc (relatively common, especially with the statistical pollers that use xor_into_buf) are removed. Counters wrap at 256.
* Pass by const reference so larger structs can be used with xor_into_buf templatelloyd2008-11-231-1/+1
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* Move xor_into_buf to xor_buf.cpp. Also add a new template wrapper forlloyd2008-11-231-10/+11
| | | | xoring integer values in.
* Add xor_into_buf. Add Doxygen comments for xor_buflloyd2008-11-231-10/+32
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* Move util functions into utils/ modulelloyd2008-09-281-0/+65