1*906afcb8SAndy Fiddaman /***********************************************************************
2*906afcb8SAndy Fiddaman * *
3*906afcb8SAndy Fiddaman * This software is part of the ast package *
4*906afcb8SAndy Fiddaman * Copyright (c) 1996-2011 AT&T Intellectual Property *
5*906afcb8SAndy Fiddaman * and is licensed under the *
6*906afcb8SAndy Fiddaman * Eclipse Public License, Version 1.0 *
7*906afcb8SAndy Fiddaman * by AT&T Intellectual Property *
8*906afcb8SAndy Fiddaman * *
9*906afcb8SAndy Fiddaman * A copy of the License is available at *
10*906afcb8SAndy Fiddaman * http://www.eclipse.org/org/documents/epl-v10.html *
11*906afcb8SAndy Fiddaman * (with md5 checksum b35adb5213ca9657e911e9befb180842) *
12*906afcb8SAndy Fiddaman * *
13*906afcb8SAndy Fiddaman * Information and Software Systems Research *
14*906afcb8SAndy Fiddaman * AT&T Research *
15*906afcb8SAndy Fiddaman * Florham Park NJ *
16*906afcb8SAndy Fiddaman * *
17*906afcb8SAndy Fiddaman * Glenn Fowler <gsf@research.att.com> *
18*906afcb8SAndy Fiddaman * *
19*906afcb8SAndy Fiddaman ***********************************************************************/
20*906afcb8SAndy Fiddaman #pragma prototyped
21*906afcb8SAndy Fiddaman
22*906afcb8SAndy Fiddaman /*
23*906afcb8SAndy Fiddaman * prng
24*906afcb8SAndy Fiddaman */
25*906afcb8SAndy Fiddaman
26*906afcb8SAndy Fiddaman #include <fnv.h>
27*906afcb8SAndy Fiddaman
28*906afcb8SAndy Fiddaman #define prng_description \
29*906afcb8SAndy Fiddaman "32 bit PRNG (pseudo random number generator) hash."
30*906afcb8SAndy Fiddaman #define prng_options "\
31*906afcb8SAndy Fiddaman [+mpy?The 32 bit PRNG multiplier.]:[number:=0x01000193]\
32*906afcb8SAndy Fiddaman [+add?The 32 bit PRNG addend.]:[number:=0]\
33*906afcb8SAndy Fiddaman [+init?The PRNG initial value. 0xffffffff is used if \anumber\a is omitted.]:?[number:=0x811c9dc5]\
34*906afcb8SAndy Fiddaman "
35*906afcb8SAndy Fiddaman #define prng_match "prng"
36*906afcb8SAndy Fiddaman #define prng_done long_done
37*906afcb8SAndy Fiddaman #define prng_print long_print
38*906afcb8SAndy Fiddaman #define prng_data long_data
39*906afcb8SAndy Fiddaman #define prng_scale 0
40*906afcb8SAndy Fiddaman
41*906afcb8SAndy Fiddaman typedef uint32_t Prngnum_t;
42*906afcb8SAndy Fiddaman
43*906afcb8SAndy Fiddaman typedef struct Prng_s
44*906afcb8SAndy Fiddaman {
45*906afcb8SAndy Fiddaman _SUM_PUBLIC_
46*906afcb8SAndy Fiddaman _SUM_PRIVATE_
47*906afcb8SAndy Fiddaman _INTEGRAL_PRIVATE_
48*906afcb8SAndy Fiddaman Prngnum_t init;
49*906afcb8SAndy Fiddaman Prngnum_t mpy;
50*906afcb8SAndy Fiddaman Prngnum_t add;
51*906afcb8SAndy Fiddaman } Prng_t;
52*906afcb8SAndy Fiddaman
53*906afcb8SAndy Fiddaman static Sum_t*
prng_open(const Method_t * method,const char * name)54*906afcb8SAndy Fiddaman prng_open(const Method_t* method, const char* name)
55*906afcb8SAndy Fiddaman {
56*906afcb8SAndy Fiddaman register Prng_t* sum;
57*906afcb8SAndy Fiddaman register const char* s;
58*906afcb8SAndy Fiddaman register const char* t;
59*906afcb8SAndy Fiddaman register const char* v;
60*906afcb8SAndy Fiddaman register int i;
61*906afcb8SAndy Fiddaman
62*906afcb8SAndy Fiddaman if (sum = newof(0, Prng_t, 1, 0))
63*906afcb8SAndy Fiddaman {
64*906afcb8SAndy Fiddaman sum->method = (Method_t*)method;
65*906afcb8SAndy Fiddaman sum->name = name;
66*906afcb8SAndy Fiddaman }
67*906afcb8SAndy Fiddaman s = name;
68*906afcb8SAndy Fiddaman while (*(t = s))
69*906afcb8SAndy Fiddaman {
70*906afcb8SAndy Fiddaman for (t = s, v = 0; *s && *s != '-'; s++)
71*906afcb8SAndy Fiddaman if (*s == '=' && !v)
72*906afcb8SAndy Fiddaman v = s;
73*906afcb8SAndy Fiddaman i = (v ? v : s) - t;
74*906afcb8SAndy Fiddaman if (isdigit(*t) || v && strneq(t, "mpy", i) && (t = v + 1))
75*906afcb8SAndy Fiddaman sum->mpy = strtoul(t, NiL, 0);
76*906afcb8SAndy Fiddaman else if (strneq(t, "add", i))
77*906afcb8SAndy Fiddaman sum->add = v ? strtoul(v + 1, NiL, 0) : ~sum->add;
78*906afcb8SAndy Fiddaman else if (strneq(t, "init", i))
79*906afcb8SAndy Fiddaman sum->init = v ? strtoul(v + 1, NiL, 0) : ~sum->init;
80*906afcb8SAndy Fiddaman if (*s == '-')
81*906afcb8SAndy Fiddaman s++;
82*906afcb8SAndy Fiddaman }
83*906afcb8SAndy Fiddaman if (!sum->mpy)
84*906afcb8SAndy Fiddaman {
85*906afcb8SAndy Fiddaman sum->mpy = FNV_MULT;
86*906afcb8SAndy Fiddaman if (!sum->init)
87*906afcb8SAndy Fiddaman sum->init = FNV_INIT;
88*906afcb8SAndy Fiddaman }
89*906afcb8SAndy Fiddaman return (Sum_t*)sum;
90*906afcb8SAndy Fiddaman }
91*906afcb8SAndy Fiddaman
92*906afcb8SAndy Fiddaman static int
prng_init(Sum_t * p)93*906afcb8SAndy Fiddaman prng_init(Sum_t* p)
94*906afcb8SAndy Fiddaman {
95*906afcb8SAndy Fiddaman Prng_t* sum = (Prng_t*)p;
96*906afcb8SAndy Fiddaman
97*906afcb8SAndy Fiddaman sum->sum = sum->init;
98*906afcb8SAndy Fiddaman return 0;
99*906afcb8SAndy Fiddaman }
100*906afcb8SAndy Fiddaman
101*906afcb8SAndy Fiddaman static int
prng_block(Sum_t * p,const void * s,size_t n)102*906afcb8SAndy Fiddaman prng_block(Sum_t* p, const void* s, size_t n)
103*906afcb8SAndy Fiddaman {
104*906afcb8SAndy Fiddaman Prng_t* sum = (Prng_t*)p;
105*906afcb8SAndy Fiddaman register Prngnum_t c = sum->sum;
106*906afcb8SAndy Fiddaman register unsigned char* b = (unsigned char*)s;
107*906afcb8SAndy Fiddaman register unsigned char* e = b + n;
108*906afcb8SAndy Fiddaman
109*906afcb8SAndy Fiddaman while (b < e)
110*906afcb8SAndy Fiddaman c = c * sum->mpy + sum->add + *b++;
111*906afcb8SAndy Fiddaman sum->sum = c;
112*906afcb8SAndy Fiddaman return 0;
113*906afcb8SAndy Fiddaman }
114