cf6509dde9
Take care of most of include/*.h. I punted on extern.h. For both src/*.c and include/*.h, I used mismatched checks of width > 79 to decide which files to look at and then width > 78 to decide which lines to maybe revise, so I didn't look at a bunch of the files. I don't plan to go back and do it right. Shortening lines that are 80 or wider to less than 80 is the significant part. Otherwise emacs puts a backslash in column 80 and the rest of the line of text on the next line of the screen, making things harder to read.
89 lines
3.2 KiB
C
89 lines
3.2 KiB
C
/* CC0 (Public domain) - see http://creativecommons.org/publicdomain/zero/1.0/ for details */
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#if !defined(_isaac64_H)
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# define _isaac64_H (1)
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typedef struct isaac64_ctx isaac64_ctx;
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#define ISAAC64_SZ_LOG (8)
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#define ISAAC64_SZ (1<<ISAAC64_SZ_LOG)
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#define ISAAC64_SEED_SZ_MAX (ISAAC64_SZ<<3)
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/*ISAAC is the most advanced of a series of pseudo-random number generators
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designed by Robert J. Jenkins Jr. in 1996.
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http://www.burtleburtle.net/bob/rand/isaac.html
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This is the 64-bit version.
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To quote:
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ISAAC-64 generates a different sequence than ISAAC, but it uses the same
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principles.
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It uses 64-bit arithmetic.
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It generates a 64-bit result every 19 instructions.
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All cycles are at least 2**72 values, and the average cycle length is
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2**16583.*/
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struct isaac64_ctx{
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unsigned n;
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uint64_t r[ISAAC64_SZ];
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uint64_t m[ISAAC64_SZ];
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uint64_t a;
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uint64_t b;
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uint64_t c;
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};
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/**
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* isaac64_init - Initialize an instance of ISAAC64 random number generator.
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* @_ctx: The ISAAC64 instance to initialize.
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* @_seed: The specified seed bytes.
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* This may be NULL if _nseed is less than or equal to zero.
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* @_nseed: The number of bytes to use for the seed.
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* If this is greater than ISAAC64_SEED_SZ_MAX, the extra bytes are
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* ignored.
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*/
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void isaac64_init(isaac64_ctx *_ctx,const unsigned char *_seed,int _nseed);
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/**
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* isaac64_reseed - Mix a new batch of entropy into the current state.
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* To reset ISAAC64 to a known state, call isaac64_init() again instead.
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* @_ctx: The instance to reseed.
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* @_seed: The specified seed bytes.
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* This may be NULL if _nseed is zero.
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* @_nseed: The number of bytes to use for the seed.
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* If this is greater than ISAAC64_SEED_SZ_MAX, the extra bytes are
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* ignored.
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*/
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void isaac64_reseed(isaac64_ctx *_ctx,const unsigned char *_seed,int _nseed);
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/**
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* isaac64_next_uint64 - Return the next random 64-bit value.
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* @_ctx: The ISAAC64 instance to generate the value with.
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*/
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uint64_t isaac64_next_uint64(isaac64_ctx *_ctx);
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/**
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* isaac64_next_uint - Uniform random integer less than the given value.
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* @_ctx: The ISAAC64 instance to generate the value with.
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* @_n: The upper bound on the range of numbers returned (not inclusive).
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* This must be greater than zero and less than 2**64.
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* To return integers in the full range 0...2**64-1, use
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* isaac64_next_uint64() instead.
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* Return: An integer uniformly distributed between 0 and _n-1 (inclusive).
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*/
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uint64_t isaac64_next_uint(isaac64_ctx *_ctx,uint64_t _n);
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/**
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* isaac64_next_float - Uniform random float in the range [0,1).
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* @_ctx: The ISAAC64 instance to generate the value with.
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* Returns a high-quality float uniformly distributed between 0 (inclusive)
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* and 1 (exclusive).
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* All of the float's mantissa bits are random, e.g., the least significant
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* bit may still be non-zero even if the value is less than 0.5, and any
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* representable float in the range [0,1) has a chance to be returned, though
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* values very close to zero become increasingly unlikely.
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* To generate cheaper float values that do not have these properties, use
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* ldexpf((float)isaac64_next_uint64(_ctx),-64);
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*/
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#endif
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