Index: head/include/stdlib.h =================================================================== --- head/include/stdlib.h (revision 303341) +++ head/include/stdlib.h (revision 303342) @@ -1,328 +1,328 @@ /*- * Copyright (c) 1990, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)stdlib.h 8.5 (Berkeley) 5/19/95 * $FreeBSD$ */ #ifndef _STDLIB_H_ #define _STDLIB_H_ #include #include #include #if __BSD_VISIBLE #ifndef _RUNE_T_DECLARED typedef __rune_t rune_t; #define _RUNE_T_DECLARED #endif #endif #ifndef _SIZE_T_DECLARED typedef __size_t size_t; #define _SIZE_T_DECLARED #endif #ifndef __cplusplus #ifndef _WCHAR_T_DECLARED typedef ___wchar_t wchar_t; #define _WCHAR_T_DECLARED #endif #endif typedef struct { int quot; /* quotient */ int rem; /* remainder */ } div_t; typedef struct { long quot; long rem; } ldiv_t; #define EXIT_FAILURE 1 #define EXIT_SUCCESS 0 #define RAND_MAX 0x7ffffffd __BEGIN_DECLS #ifdef _XLOCALE_H_ #include #endif extern int __mb_cur_max; extern int ___mb_cur_max(void); #define MB_CUR_MAX (___mb_cur_max()) _Noreturn void abort(void); int abs(int) __pure2; int atexit(void (*)(void)); double atof(const char *); int atoi(const char *); long atol(const char *); void *bsearch(const void *, const void *, size_t, size_t, int (*)(const void *, const void *)); void *calloc(size_t, size_t) __malloc_like __result_use_check __alloc_size(1) __alloc_size(2); div_t div(int, int) __pure2; _Noreturn void exit(int); void free(void *); char *getenv(const char *); long labs(long) __pure2; ldiv_t ldiv(long, long) __pure2; void *malloc(size_t) __malloc_like __result_use_check __alloc_size(1); int mblen(const char *, size_t); size_t mbstowcs(wchar_t * __restrict , const char * __restrict, size_t); int mbtowc(wchar_t * __restrict, const char * __restrict, size_t); void qsort(void *, size_t, size_t, int (*)(const void *, const void *)); int rand(void); void *realloc(void *, size_t) __result_use_check __alloc_size(2); void srand(unsigned); double strtod(const char * __restrict, char ** __restrict); float strtof(const char * __restrict, char ** __restrict); long strtol(const char * __restrict, char ** __restrict, int); long double strtold(const char * __restrict, char ** __restrict); unsigned long strtoul(const char * __restrict, char ** __restrict, int); int system(const char *); int wctomb(char *, wchar_t); size_t wcstombs(char * __restrict, const wchar_t * __restrict, size_t); /* * Functions added in C99 which we make conditionally available in the * BSD^C89 namespace if the compiler supports `long long'. * The #if test is more complicated than it ought to be because * __BSD_VISIBLE implies __ISO_C_VISIBLE == 1999 *even if* `long long' * is not supported in the compilation environment (which therefore means * that it can't really be ISO C99). * * (The only other extension made by C99 in thie header is _Exit().) */ #if __ISO_C_VISIBLE >= 1999 || defined(__cplusplus) #ifdef __LONG_LONG_SUPPORTED /* LONGLONG */ typedef struct { long long quot; long long rem; } lldiv_t; /* LONGLONG */ long long atoll(const char *); /* LONGLONG */ long long llabs(long long) __pure2; /* LONGLONG */ lldiv_t lldiv(long long, long long) __pure2; /* LONGLONG */ long long strtoll(const char * __restrict, char ** __restrict, int); /* LONGLONG */ unsigned long long strtoull(const char * __restrict, char ** __restrict, int); #endif /* __LONG_LONG_SUPPORTED */ _Noreturn void _Exit(int); #endif /* __ISO_C_VISIBLE >= 1999 */ /* * If we're in a mode greater than C99, expose C11 functions. */ #if __ISO_C_VISIBLE >= 2011 || __cplusplus >= 201103L void * aligned_alloc(size_t, size_t) __malloc_like __alloc_align(1) __alloc_size(2); int at_quick_exit(void (*)(void)); _Noreturn void quick_exit(int); #endif /* __ISO_C_VISIBLE >= 2011 */ /* * Extensions made by POSIX relative to C. */ #if __POSIX_VISIBLE >= 199506 || __XSI_VISIBLE char *realpath(const char * __restrict, char * __restrict); #endif #if __POSIX_VISIBLE >= 199506 int rand_r(unsigned *); /* (TSF) */ #endif #if __POSIX_VISIBLE >= 200112 int posix_memalign(void **, size_t, size_t) __nonnull(1); /* (ADV) */ int setenv(const char *, const char *, int); int unsetenv(const char *); #endif #if __POSIX_VISIBLE >= 200809 || __XSI_VISIBLE int getsubopt(char **, char *const *, char **); #ifndef _MKDTEMP_DECLARED char *mkdtemp(char *); #define _MKDTEMP_DECLARED #endif #ifndef _MKSTEMP_DECLARED int mkstemp(char *); #define _MKSTEMP_DECLARED #endif #endif /* __POSIX_VISIBLE >= 200809 || __XSI_VISIBLE */ /* * The only changes to the XSI namespace in revision 6 were the deletion * of the ttyslot() and valloc() functions, which FreeBSD never declared * in this header. For revision 7, ecvt(), fcvt(), and gcvt(), which * FreeBSD also does not have, and mktemp(), are to be deleted. */ #if __XSI_VISIBLE /* XXX XSI requires pollution from here. We'd rather not. */ long a64l(const char *); double drand48(void); /* char *ecvt(double, int, int * __restrict, int * __restrict); */ double erand48(unsigned short[3]); /* char *fcvt(double, int, int * __restrict, int * __restrict); */ /* char *gcvt(double, int, int * __restrict, int * __restrict); */ int grantpt(int); -char *initstate(unsigned long /* XSI requires u_int */, char *, long); +char *initstate(unsigned int, char *, size_t); long jrand48(unsigned short[3]); char *l64a(long); void lcong48(unsigned short[7]); long lrand48(void); #if !defined(_MKTEMP_DECLARED) && (__BSD_VISIBLE || __XSI_VISIBLE <= 600) char *mktemp(char *); #define _MKTEMP_DECLARED #endif long mrand48(void); long nrand48(unsigned short[3]); int posix_openpt(int); char *ptsname(int); int putenv(char *); long random(void); unsigned short *seed48(unsigned short[3]); #ifndef _SETKEY_DECLARED int setkey(const char *); #define _SETKEY_DECLARED #endif char *setstate(/* const */ char *); void srand48(long); -void srandom(unsigned long); +void srandom(unsigned int); int unlockpt(int); #endif /* __XSI_VISIBLE */ #if __BSD_VISIBLE extern const char *malloc_conf; extern void (*malloc_message)(void *, const char *); /* * The alloca() function can't be implemented in C, and on some * platforms it can't be implemented at all as a callable function. * The GNU C compiler provides a built-in alloca() which we can use; * in all other cases, provide a prototype, mainly to pacify various * incarnations of lint. On platforms where alloca() is not in libc, * programs which use it will fail to link when compiled with non-GNU * compilers. */ #if __GNUC__ >= 2 || defined(__INTEL_COMPILER) #undef alloca /* some GNU bits try to get cute and define this on their own */ #define alloca(sz) __builtin_alloca(sz) #elif defined(lint) void *alloca(size_t); #endif void abort2(const char *, int, void **) __dead2; __uint32_t arc4random(void); void arc4random_addrandom(unsigned char *, int); void arc4random_buf(void *, size_t); void arc4random_stir(void); __uint32_t arc4random_uniform(__uint32_t); #ifdef __BLOCKS__ int atexit_b(void (^)(void)); void *bsearch_b(const void *, const void *, size_t, size_t, int (^)(const void *, const void *)); #endif char *getbsize(int *, long *); /* getcap(3) functions */ char *cgetcap(char *, const char *, int); int cgetclose(void); int cgetent(char **, char **, const char *); int cgetfirst(char **, char **); int cgetmatch(const char *, const char *); int cgetnext(char **, char **); int cgetnum(char *, const char *, long *); int cgetset(const char *); int cgetstr(char *, const char *, char **); int cgetustr(char *, const char *, char **); int daemon(int, int); char *devname(__dev_t, __mode_t); char *devname_r(__dev_t, __mode_t, char *, int); char *fdevname(int); char *fdevname_r(int, char *, int); int getloadavg(double [], int); const char * getprogname(void); int heapsort(void *, size_t, size_t, int (*)(const void *, const void *)); #ifdef __BLOCKS__ int heapsort_b(void *, size_t, size_t, int (^)(const void *, const void *)); void qsort_b(void *, size_t, size_t, int (^)(const void *, const void *)); #endif int l64a_r(long, char *, int); int mergesort(void *, size_t, size_t, int (*)(const void *, const void *)); #ifdef __BLOCKS__ int mergesort_b(void *, size_t, size_t, int (^)(const void *, const void *)); #endif int mkostemp(char *, int); int mkostemps(char *, int, int); void qsort_r(void *, size_t, size_t, void *, int (*)(void *, const void *, const void *)); int radixsort(const unsigned char **, int, const unsigned char *, unsigned); void *reallocarray(void *, size_t, size_t) __result_use_check __alloc_size(2) __alloc_size(3); void *reallocf(void *, size_t) __alloc_size(2); int rpmatch(const char *); void setprogname(const char *); int sradixsort(const unsigned char **, int, const unsigned char *, unsigned); void sranddev(void); void srandomdev(void); long long strtonum(const char *, long long, long long, const char **); /* Deprecated interfaces, to be removed in FreeBSD 6.0. */ __int64_t strtoq(const char *, char **, int); __uint64_t strtouq(const char *, char **, int); extern char *suboptarg; /* getsubopt(3) external variable */ #endif /* __BSD_VISIBLE */ __END_DECLS #endif /* !_STDLIB_H_ */ Index: head/lib/libc/stdlib/random.3 =================================================================== --- head/lib/libc/stdlib/random.3 (revision 303341) +++ head/lib/libc/stdlib/random.3 (revision 303342) @@ -1,197 +1,197 @@ .\" Copyright (c) 1983, 1991, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)random.3 8.1 (Berkeley) 6/4/93 .\" $FreeBSD$ .\" -.Dd April 2, 2013 +.Dd July 26, 2016 .Dt RANDOM 3 .Os .Sh NAME .Nm random , .Nm srandom , .Nm srandomdev , .Nm initstate , .Nm setstate .Nd better random number generator; routines for changing generators .Sh LIBRARY .Lb libc .Sh SYNOPSIS .In stdlib.h .Ft long .Fn random void .Ft void -.Fn srandom "unsigned long seed" +.Fn srandom "unsigned int seed" .Ft void .Fn srandomdev void .Ft char * -.Fn initstate "unsigned long seed" "char *state" "long n" +.Fn initstate "unsigned int seed" "char *state" "size_t n" .Ft char * .Fn setstate "char *state" .Sh DESCRIPTION .Bf -symbolic The functions described in this manual page are not secure. Applications which require unpredictable random numbers should use .Xr arc4random 3 instead. .Ef .Pp The .Fn random function uses a non-linear additive feedback random number generator employing a default table of size 31 long integers to return successive pseudo-random numbers in the range from 0 to .if t 2\u\s731\s10\d\(mi1. .if n (2**31)\(mi1. The period of this random number generator is very large, approximately .if t 16\(mu(2\u\s731\s10\d\(mi1). .if n 16*((2**31)\(mi1). .Pp The .Fn random and .Fn srandom functions have (almost) the same calling sequence and initialization properties as the .Xr rand 3 and .Xr srand 3 functions. The difference is that .Xr rand 3 produces a much less random sequence \(em in fact, the low dozen bits generated by rand go through a cyclic pattern. All the bits generated by .Fn random are usable. For example, .Sq Li random()&01 will produce a random binary value. .Pp Like .Xr rand 3 , .Fn random will by default produce a sequence of numbers that can be duplicated by calling .Fn srandom with .Ql 1 as the seed. .Pp The .Fn srandomdev routine initializes a state array using pseudo-random numbers obtained from the kernel. Note that this particular seeding procedure can generate states which are impossible to reproduce by calling .Fn srandom with any value, since the succeeding terms in the state buffer are no longer derived from the LC algorithm applied to a fixed seed. .Pp The .Fn initstate routine allows a state array, passed in as an argument, to be initialized for future use. The size of the state array (in bytes) is used by .Fn initstate to decide how sophisticated a random number generator it should use \(em the more state, the better the random numbers will be. (Current "optimal" values for the amount of state information are 8, 32, 64, 128, and 256 bytes; other amounts will be rounded down to the nearest known amount. Using less than 8 bytes will cause an error.) The seed for the initialization (which specifies a starting point for the random number sequence, and provides for restarting at the same point) is also an argument. The .Fn initstate function returns a pointer to the previous state information array. .Pp Once a state has been initialized, the .Fn setstate routine provides for rapid switching between states. The .Fn setstate function returns a pointer to the previous state array; its argument state array is used for further random number generation until the next call to .Fn initstate or .Fn setstate . .Pp Once a state array has been initialized, it may be restarted at a different point either by calling .Fn initstate (with the desired seed, the state array, and its size) or by calling both .Fn setstate (with the state array) and .Fn srandom (with the desired seed). The advantage of calling both .Fn setstate and .Fn srandom is that the size of the state array does not have to be remembered after it is initialized. .Pp With 256 bytes of state information, the period of the random number generator is greater than .if t 2\u\s769\s10\d, .if n 2**69 which should be sufficient for most purposes. .Sh DIAGNOSTICS If .Fn initstate is called with less than 8 bytes of state information, or if .Fn setstate detects that the state information has been garbled, NULL is returned. .Sh SEE ALSO .Xr arc4random 3 , .Xr lrand48 3 , .Xr rand 3 , .Xr random 4 .Sh HISTORY These functions appeared in .Bx 4.2 . .Sh AUTHORS .An Earl T. Cohen .Sh BUGS About 2/3 the speed of .Xr rand 3 . .Pp The historical implementation used to have a very weak seeding; the random sequence did not vary much with the seed. The current implementation employs a better pseudo-random number generator for the initial state calculation. Index: head/lib/libc/stdlib/random.c =================================================================== --- head/lib/libc/stdlib/random.c (revision 303341) +++ head/lib/libc/stdlib/random.c (revision 303342) @@ -1,445 +1,445 @@ /* * Copyright (c) 1983, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #if defined(LIBC_SCCS) && !defined(lint) static char sccsid[] = "@(#)random.c 8.2 (Berkeley) 5/19/95"; #endif /* LIBC_SCCS and not lint */ #include __FBSDID("$FreeBSD$"); #include "namespace.h" #include #include #include #include #include "un-namespace.h" /* * random.c: * * An improved random number generation package. In addition to the standard * rand()/srand() like interface, this package also has a special state info * interface. The initstate() routine is called with a seed, an array of * bytes, and a count of how many bytes are being passed in; this array is * then initialized to contain information for random number generation with * that much state information. Good sizes for the amount of state * information are 32, 64, 128, and 256 bytes. The state can be switched by * calling the setstate() routine with the same array as was initiallized * with initstate(). By default, the package runs with 128 bytes of state * information and generates far better random numbers than a linear * congruential generator. If the amount of state information is less than * 32 bytes, a simple linear congruential R.N.G. is used. * * Internally, the state information is treated as an array of uint32_t's; the * zeroeth element of the array is the type of R.N.G. being used (small * integer); the remainder of the array is the state information for the * R.N.G. Thus, 32 bytes of state information will give 7 ints worth of * state information, which will allow a degree seven polynomial. (Note: * the zeroeth word of state information also has some other information * stored in it -- see setstate() for details). * * The random number generation technique is a linear feedback shift register * approach, employing trinomials (since there are fewer terms to sum up that * way). In this approach, the least significant bit of all the numbers in * the state table will act as a linear feedback shift register, and will * have period 2^deg - 1 (where deg is the degree of the polynomial being * used, assuming that the polynomial is irreducible and primitive). The * higher order bits will have longer periods, since their values are also * influenced by pseudo-random carries out of the lower bits. The total * period of the generator is approximately deg*(2**deg - 1); thus doubling * the amount of state information has a vast influence on the period of the * generator. Note: the deg*(2**deg - 1) is an approximation only good for * large deg, when the period of the shift is the dominant factor. * With deg equal to seven, the period is actually much longer than the * 7*(2**7 - 1) predicted by this formula. * * Modified 28 December 1994 by Jacob S. Rosenberg. * The following changes have been made: * All references to the type u_int have been changed to unsigned long. * All references to type int have been changed to type long. Other * cleanups have been made as well. A warning for both initstate and * setstate has been inserted to the effect that on Sparc platforms * the 'arg_state' variable must be forced to begin on word boundaries. * This can be easily done by casting a long integer array to char *. * The overall logic has been left STRICTLY alone. This software was * tested on both a VAX and Sun SpacsStation with exactly the same * results. The new version and the original give IDENTICAL results. * The new version is somewhat faster than the original. As the * documentation says: "By default, the package runs with 128 bytes of * state information and generates far better random numbers than a linear * congruential generator. If the amount of state information is less than * 32 bytes, a simple linear congruential R.N.G. is used." For a buffer of * 128 bytes, this new version runs about 19 percent faster and for a 16 * byte buffer it is about 5 percent faster. */ /* * For each of the currently supported random number generators, we have a * break value on the amount of state information (you need at least this * many bytes of state info to support this random number generator), a degree * for the polynomial (actually a trinomial) that the R.N.G. is based on, and * the separation between the two lower order coefficients of the trinomial. */ #define TYPE_0 0 /* linear congruential */ #define BREAK_0 8 #define DEG_0 0 #define SEP_0 0 #define TYPE_1 1 /* x**7 + x**3 + 1 */ #define BREAK_1 32 #define DEG_1 7 #define SEP_1 3 #define TYPE_2 2 /* x**15 + x + 1 */ #define BREAK_2 64 #define DEG_2 15 #define SEP_2 1 #define TYPE_3 3 /* x**31 + x**3 + 1 */ #define BREAK_3 128 #define DEG_3 31 #define SEP_3 3 #define TYPE_4 4 /* x**63 + x + 1 */ #define BREAK_4 256 #define DEG_4 63 #define SEP_4 1 /* * Array versions of the above information to make code run faster -- * relies on fact that TYPE_i == i. */ #define MAX_TYPES 5 /* max number of types above */ #define NSHUFF 50 /* to drop some "seed -> 1st value" linearity */ static const int degrees[MAX_TYPES] = { DEG_0, DEG_1, DEG_2, DEG_3, DEG_4 }; static const int seps [MAX_TYPES] = { SEP_0, SEP_1, SEP_2, SEP_3, SEP_4 }; /* * Initially, everything is set up as if from: * * initstate(1, randtbl, 128); * * Note that this initialization takes advantage of the fact that srandom() * advances the front and rear pointers 10*rand_deg times, and hence the * rear pointer which starts at 0 will also end up at zero; thus the zeroeth * element of the state information, which contains info about the current * position of the rear pointer is just * * MAX_TYPES * (rptr - state) + TYPE_3 == TYPE_3. */ static uint32_t randtbl[DEG_3 + 1] = { TYPE_3, 0x2cf41758, 0x27bb3711, 0x4916d4d1, 0x7b02f59f, 0x9b8e28eb, 0xc0e80269, 0x696f5c16, 0x878f1ff5, 0x52d9c07f, 0x916a06cd, 0xb50b3a20, 0x2776970a, 0xee4eb2a6, 0xe94640ec, 0xb1d65612, 0x9d1ed968, 0x1043f6b7, 0xa3432a76, 0x17eacbb9, 0x3c09e2eb, 0x4f8c2b3, 0x708a1f57, 0xee341814, 0x95d0e4d2, 0xb06f216c, 0x8bd2e72e, 0x8f7c38d7, 0xcfc6a8fc, 0x2a59495, 0xa20d2a69, 0xe29d12d1 }; /* * fptr and rptr are two pointers into the state info, a front and a rear * pointer. These two pointers are always rand_sep places aparts, as they * cycle cyclically through the state information. (Yes, this does mean we * could get away with just one pointer, but the code for random() is more * efficient this way). The pointers are left positioned as they would be * from the call * * initstate(1, randtbl, 128); * * (The position of the rear pointer, rptr, is really 0 (as explained above * in the initialization of randtbl) because the state table pointer is set * to point to randtbl[1] (as explained below). */ static uint32_t *fptr = &randtbl[SEP_3 + 1]; static uint32_t *rptr = &randtbl[1]; /* * The following things are the pointer to the state information table, the * type of the current generator, the degree of the current polynomial being * used, and the separation between the two pointers. Note that for efficiency * of random(), we remember the first location of the state information, not * the zeroeth. Hence it is valid to access state[-1], which is used to * store the type of the R.N.G. Also, we remember the last location, since * this is more efficient than indexing every time to find the address of * the last element to see if the front and rear pointers have wrapped. */ static uint32_t *state = &randtbl[1]; static int rand_type = TYPE_3; static int rand_deg = DEG_3; static int rand_sep = SEP_3; static uint32_t *end_ptr = &randtbl[DEG_3 + 1]; static inline uint32_t good_rand(uint32_t ctx) { /* * Compute x = (7^5 * x) mod (2^31 - 1) * wihout overflowing 31 bits: * (2^31 - 1) = 127773 * (7^5) + 2836 * From "Random number generators: good ones are hard to find", * Park and Miller, Communications of the ACM, vol. 31, no. 10, * October 1988, p. 1195. */ int32_t hi, lo, x; /* Transform to [1, 0x7ffffffe] range. */ x = (ctx % 0x7ffffffe) + 1; hi = x / 127773; lo = x % 127773; x = 16807 * lo - 2836 * hi; if (x < 0) x += 0x7fffffff; /* Transform to [0, 0x7ffffffd] range. */ return (x - 1); } /* * srandom: * * Initialize the random number generator based on the given seed. If the * type is the trivial no-state-information type, just remember the seed. * Otherwise, initializes state[] based on the given "seed" via a linear * congruential generator. Then, the pointers are set to known locations * that are exactly rand_sep places apart. Lastly, it cycles the state * information a given number of times to get rid of any initial dependencies * introduced by the L.C.R.N.G. Note that the initialization of randtbl[] * for default usage relies on values produced by this routine. */ void -srandom(unsigned long x) +srandom(unsigned int x) { int i, lim; state[0] = (uint32_t)x; if (rand_type == TYPE_0) lim = NSHUFF; else { for (i = 1; i < rand_deg; i++) state[i] = good_rand(state[i - 1]); fptr = &state[rand_sep]; rptr = &state[0]; lim = 10 * rand_deg; } for (i = 0; i < lim; i++) (void)random(); } /* * srandomdev: * * Many programs choose the seed value in a totally predictable manner. * This often causes problems. We seed the generator using pseudo-random * data from the kernel. * * Note that this particular seeding procedure can generate states * which are impossible to reproduce by calling srandom() with any * value, since the succeeding terms in the state buffer are no longer * derived from the LC algorithm applied to a fixed seed. */ void srandomdev(void) { int mib[2]; size_t len; if (rand_type == TYPE_0) len = sizeof(state[0]); else len = rand_deg * sizeof(state[0]); mib[0] = CTL_KERN; mib[1] = KERN_ARND; sysctl(mib, 2, state, &len, NULL, 0); if (rand_type != TYPE_0) { fptr = &state[rand_sep]; rptr = &state[0]; } } /* * initstate: * * Initialize the state information in the given array of n bytes for future * random number generation. Based on the number of bytes we are given, and * the break values for the different R.N.G.'s, we choose the best (largest) * one we can and set things up for it. srandom() is then called to * initialize the state information. * * Note that on return from srandom(), we set state[-1] to be the type * multiplexed with the current value of the rear pointer; this is so * successive calls to initstate() won't lose this information and will be * able to restart with setstate(). * * Note: the first thing we do is save the current state, if any, just like * setstate() so that it doesn't matter when initstate is called. * * Returns a pointer to the old state. * * Note: The Sparc platform requires that arg_state begin on an int * word boundary; otherwise a bus error will occur. Even so, lint will * complain about mis-alignment, but you should disregard these messages. */ char * -initstate(unsigned long seed, char *arg_state, long n) +initstate(unsigned int seed, char *arg_state, size_t n) { char *ostate = (char *)(&state[-1]); uint32_t *int_arg_state = (uint32_t *)arg_state; if (n < BREAK_0) return (NULL); if (rand_type == TYPE_0) state[-1] = rand_type; else state[-1] = MAX_TYPES * (rptr - state) + rand_type; if (n < BREAK_1) { rand_type = TYPE_0; rand_deg = DEG_0; rand_sep = SEP_0; } else if (n < BREAK_2) { rand_type = TYPE_1; rand_deg = DEG_1; rand_sep = SEP_1; } else if (n < BREAK_3) { rand_type = TYPE_2; rand_deg = DEG_2; rand_sep = SEP_2; } else if (n < BREAK_4) { rand_type = TYPE_3; rand_deg = DEG_3; rand_sep = SEP_3; } else { rand_type = TYPE_4; rand_deg = DEG_4; rand_sep = SEP_4; } state = int_arg_state + 1; /* first location */ end_ptr = &state[rand_deg]; /* must set end_ptr before srandom */ srandom(seed); if (rand_type == TYPE_0) int_arg_state[0] = rand_type; else int_arg_state[0] = MAX_TYPES * (rptr - state) + rand_type; return (ostate); } /* * setstate: * * Restore the state from the given state array. * * Note: it is important that we also remember the locations of the pointers * in the current state information, and restore the locations of the pointers * from the old state information. This is done by multiplexing the pointer * location into the zeroeth word of the state information. * * Note that due to the order in which things are done, it is OK to call * setstate() with the same state as the current state. * * Returns a pointer to the old state information. * * Note: The Sparc platform requires that arg_state begin on an int * word boundary; otherwise a bus error will occur. Even so, lint will * complain about mis-alignment, but you should disregard these messages. */ char * setstate(char *arg_state) { uint32_t *new_state = (uint32_t *)arg_state; uint32_t type = new_state[0] % MAX_TYPES; uint32_t rear = new_state[0] / MAX_TYPES; char *ostate = (char *)(&state[-1]); if (type != TYPE_0 && rear >= degrees[type]) return (NULL); if (rand_type == TYPE_0) state[-1] = rand_type; else state[-1] = MAX_TYPES * (rptr - state) + rand_type; rand_type = type; rand_deg = degrees[type]; rand_sep = seps[type]; state = new_state + 1; if (rand_type != TYPE_0) { rptr = &state[rear]; fptr = &state[(rear + rand_sep) % rand_deg]; } end_ptr = &state[rand_deg]; /* set end_ptr too */ return (ostate); } /* * random: * * If we are using the trivial TYPE_0 R.N.G., just do the old linear * congruential bit. Otherwise, we do our fancy trinomial stuff, which is * the same in all the other cases due to all the global variables that have * been set up. The basic operation is to add the number at the rear pointer * into the one at the front pointer. Then both pointers are advanced to * the next location cyclically in the table. The value returned is the sum * generated, reduced to 31 bits by throwing away the "least random" low bit. * * Note: the code takes advantage of the fact that both the front and * rear pointers can't wrap on the same call by not testing the rear * pointer if the front one has wrapped. * * Returns a 31-bit random number. */ long random(void) { uint32_t i; uint32_t *f, *r; if (rand_type == TYPE_0) { i = state[0]; state[0] = i = good_rand(i); } else { /* * Use local variables rather than static variables for speed. */ f = fptr; r = rptr; *f += *r; i = *f >> 1; /* chucking least random bit */ if (++f >= end_ptr) { f = state; ++r; } else if (++r >= end_ptr) { r = state; } fptr = f; rptr = r; } return ((long)i); }