folkert/simh-testsetgenerator
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

SCP: Enable use of local rand() and scrand() implementation

Browse source
This commit is contained in:
Mark Pizzolato 2019-04-03 09:43:47 -07:00
parent bb2368ab8d
commit 64fa357bf9
2 changed files with 21 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

23
scp.c
View file

@ -8707,7 +8707,7 @@ for (i = 0, j = addr; i < sim_emax; i++, j = j + dptr->aincr) {
reason = SCPE_IOERR; reason = SCPE_IOERR;
break; break;
} }
sim_fread (&sim_eval[i], sz, 1, uptr->fileref); (void)sim_fread (&sim_eval[i], sz, 1, uptr->fileref);
if ((feof (uptr->fileref)) && if ((feof (uptr->fileref)) &&
!(uptr->flags & UNIT_FIX)) { !(uptr->flags & UNIT_FIX)) {
reason = SCPE_EOF; reason = SCPE_EOF;
@ -14534,19 +14534,32 @@ return cptr;
/* /*
* To avoid Coverity complaints about the use of rand() we define the function locally * To avoid Coverity complaints about the use of rand() we define the function locally
* This implementation of Lehmer's minimal standard algorithm is derived
* from the integer solution provided in:
" "Communications of the ACM, October 1988, Volume 31, Number 10, page 1195"
*/ */
static uint32 sim_rand_seed; static int32 sim_rand_seed = 2;
void sim_srand (unsigned int seed) void sim_srand (unsigned int seed)
{ {
sim_rand_seed = (uint32)seed; /* Keep the seed within 1..RAND_MAX */
sim_rand_seed = (int32)(seed % RAND_MAX) + 1;
} }
int sim_rand () int sim_rand ()
{ {
sim_rand_seed = sim_rand_seed * 214013 + 2531011; const int32 a = 16807;
return (sim_rand_seed >> 16) & RAND_MAX; const int32 q = 127773; /* (RAND_MAX + 1) / a */
const int32 r = 2836; /* (RAND_MAX + 1) % a */
int32 lo, hi;
hi = sim_rand_seed / q;
lo = sim_rand_seed % q;
sim_rand_seed = a * lo - r * hi;
if (sim_rand_seed < 0)
sim_rand_seed += RAND_MAX + 1;
return (sim_rand_seed - 1);
} }
/* /*

4
scp.h
View file

@ -236,7 +236,9 @@ int sim_rand (void);
#ifdef RAND_MAX #ifdef RAND_MAX
#undef RAND_MAX #undef RAND_MAX
#endif #endif
#define RAND_MAX 32767 #define RAND_MAX 2147483646
#define rand sim_rand
#define srand(seed) sim_srand(seed)
CONST char *get_sim_opt (int32 opt, CONST char *cptr, t_stat *st); CONST char *get_sim_opt (int32 opt, CONST char *cptr, t_stat *st);
CONST char *get_sim_sw (CONST char *cptr); CONST char *get_sim_sw (CONST char *cptr);
const char *put_switches (char *buf, size_t bufsize, uint32 sw); const char *put_switches (char *buf, size_t bufsize, uint32 sw);