--- /dev/null
+#if !defined(_isaac_H)
+# define _isaac_H (1)
+# include <stdint.h>
+
+
+
+typedef struct isaac_ctx isaac_ctx;
+
+
+
+/*This value may be lowered to reduce memory usage on embedded platforms, at
+ the cost of reducing security and increasing bias.
+ Quoting Bob Jenkins: "The current best guess is that bias is detectable after
+ 2**37 values for [ISAAC_SZ_LOG]=3, 2**45 for 4, 2**53 for 5, 2**61 for 6,
+ 2**69 for 7, and 2**77 values for [ISAAC_SZ_LOG]=8."*/
+#define ISAAC_SZ_LOG (8)
+#define ISAAC_SZ (1<<ISAAC_SZ_LOG)
+#define ISAAC_SEED_SZ_MAX (ISAAC_SZ<<2)
+
+
+
+/*ISAAC is the most advanced of a series of pseudo-random number generators
+ designed by Robert J. Jenkins Jr. in 1996.
+ http://www.burtleburtle.net/bob/rand/isaac.html
+ To quote:
+ No efficient method is known for deducing their internal states.
+ ISAAC requires an amortized 18.75 instructions to produce a 32-bit value.
+ There are no cycles in ISAAC shorter than 2**40 values.
+ The expected cycle length is 2**8295 values.*/
+struct isaac_ctx{
+ unsigned n;
+ uint32_t r[ISAAC_SZ];
+ uint32_t m[ISAAC_SZ];
+ uint32_t a;
+ uint32_t b;
+ uint32_t c;
+};
+
+
+/**
+ * isaac_init - Initialize an instance of the ISAAC random number generator.
+ * @_ctx: The instance to initialize.
+ * @_seed: The specified seed bytes.
+ * This may be NULL if _nseed is less than or equal to zero.
+ * @_nseed: The number of bytes to use for the seed.
+ * If this is greater than ISAAC_SEED_SZ_MAX, the extra bytes are
+ * ignored.
+ */
+void isaac_init(isaac_ctx *_ctx,const unsigned char *_seed,int _nseed);
+
+/**
+ * isaac_reseed - Mix a new batch of entropy into the current state.
+ * To reset ISAAC to a known state, call isaac_init() again instead.
+ * @_ctx: The instance to reseed.
+ * @_seed: The specified seed bytes.
+ * This may be NULL if _nseed is zero.
+ * @_nseed: The number of bytes to use for the seed.
+ * If this is greater than ISAAC_SEED_SZ_MAX, the extra bytes are
+ * ignored.
+ */
+void isaac_reseed(isaac_ctx *_ctx,const unsigned char *_seed,int _nseed);
+/**
+ * isaac_next_uint32 - Return the next random 32-bit value.
+ * @_ctx: The ISAAC instance to generate the value with.
+ */
+uint32_t isaac_next_uint32(isaac_ctx *_ctx);
+/**
+ * isaac_next_uint - Uniform random integer less than the given value.
+ * @_ctx: The ISAAC instance to generate the value with.
+ * @_n: The upper bound on the range of numbers returned (not inclusive).
+ * This must be greater than zero and less than 2**32.
+ * To return integers in the full range 0...2**32-1, use
+ * isaac_next_uint32() instead.
+ * Return: An integer uniformly distributed between 0 and _n-1 (inclusive).
+ */
+uint32_t isaac_next_uint(isaac_ctx *_ctx,uint32_t _n);
+/**
+ * isaac_next_float - Uniform random float in the range [0,1).
+ * @_ctx: The ISAAC instance to generate the value with.
+ * Returns a high-quality float uniformly distributed between 0 (inclusive)
+ * and 1 (exclusive).
+ * All of the float's mantissa bits are random, e.g., the least significant bit
+ * may still be non-zero even if the value is less than 0.5, and any
+ * representable float in the range [0,1) has a chance to be returned, though
+ * values very close to zero become increasingly unlikely.
+ * To generate cheaper float values that do not have these properties, use
+ * ldexpf((float)isaac_next_uint32(_ctx),-32);
+ */
+float isaac_next_float(isaac_ctx *_ctx);
+/**
+ * isaac_next_signed_float - Uniform random float in the range (-1,1).
+ * @_ctx: The ISAAC instance to generate the value with.
+ * Returns a high-quality float uniformly distributed between -1 and 1
+ * (exclusive).
+ * All of the float's mantissa bits are random, e.g., the least significant bit
+ * may still be non-zero even if the magnitude is less than 0.5, and any
+ * representable float in the range (-1,1) has a chance to be returned, though
+ * values very close to zero become increasingly unlikely.
+ * To generate cheaper float values that do not have these properties, use
+ * ldexpf((float)isaac_next_uint32(_ctx),-31)-1;
+ * though this returns values in the range [-1,1).
+ */
+float isaac_next_signed_float(isaac_ctx *_ctx);
+/**
+ * isaac_next_double - Uniform random double in the range [0,1).
+ * @_ctx: The ISAAC instance to generate the value with.
+ * Returns a high-quality double uniformly distributed between 0 (inclusive)
+ * and 1 (exclusive).
+ * All of the double's mantissa bits are random, e.g., the least significant
+ * bit may still be non-zero even if the value is less than 0.5, and any
+ * representable double in the range [0,1) has a chance to be returned, though
+ * values very close to zero become increasingly unlikely.
+ * To generate cheaper double values that do not have these properties, use
+ * ldexp((double)isaac_next_uint32(_ctx),-32);
+ */
+double isaac_next_double(isaac_ctx *_ctx);
+/**
+ * isaac_next_signed_double - Uniform random double in the range (-1,1).
+ * @_ctx: The ISAAC instance to generate the value with.
+ * Returns a high-quality double uniformly distributed between -1 and 1
+ * (exclusive).
+ * All of the double's mantissa bits are random, e.g., the least significant
+ * bit may still be non-zero even if the value is less than 0.5, and any
+ * representable double in the range (-1,1) has a chance to be returned,
+ * though values very close to zero become increasingly unlikely.
+ * To generate cheaper double values that do not have these properties, use
+ * ldexp((double)isaac_next_uint32(_ctx),-31)-1;
+ * though this returns values in the range [-1,1).
+ */
+double isaac_next_signed_double(isaac_ctx *_ctx);
+
+#endif
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