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random longness fixes

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git-svn-id: svn://svn.rockbox.org/rockbox/trunk@5950 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Jean-Philippe Bernardy 2005-02-15 13:28:39 +00:00
parent aac6e7d24e
commit effb196053
3 changed files with 25 additions and 23 deletions
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4
apps/plugin.h
View File

@ -259,8 +259,8 @@ struct plugin_api {
#endif
/* misc */
void (*srand)(unsigned long seed);
long (*rand)(void);
void (*srand)(unsigned int seed);
int (*rand)(void);
void (*qsort)(void *base, size_t nmemb, size_t size,
int(*compar)(const void *, const void *));
int (*kbd_input)(char* buffer, int buflen);

38
firmware/common/random.c
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@ -49,10 +49,10 @@
#define N (624) /* length of state vector */
#define M (397) /* a period parameter */
#define K (0x9908B0DFU) /* a magic constant */
#define hiBit(u) ((u) & 0x80000000U) /* mask all but highest bit of u */
#define loBit(u) ((u) & 0x00000001U) /* mask all but lowest bit of u */
#define loBits(u) ((u) & 0x7FFFFFFFU) /* mask the highest bit of u */
#define K (0x9908B0DFUL) /* a magic constant */
#define hiBit(u) ((u) & 0x80000000UL) /* mask all but highest bit of u */
#define loBit(u) ((u) & 0x00000001UL) /* mask all but lowest bit of u */
#define loBits(u) ((u) & 0x7FFFFFFFUL) /* mask the highest bit of u */
#define mixBits(u, v) (hiBit(u)|loBits(v)) /* move highest bit of u to
highest bit of v */
@ -60,7 +60,7 @@ static unsigned long state[N+1]; /* state vector + 1 to not violate ANSI C */
static unsigned long *next; /* next random value is computed from here */
static int left = -1; /* can *next++ this many times before reloading */
void srand(unsigned long seed)
void srand(unsigned int seed)
{
/*
* We initialize state[0..(N-1)] via the generator
@ -108,37 +108,37 @@ void srand(unsigned long seed)
* so-- that's why the only change I made is to restrict to odd seeds.
*/
unsigned long x = (seed | 1U) & 0xFFFFFFFFU, *s = state;
unsigned long x = (seed | 1UL) & 0xFFFFFFFFUL, *s = state;
int j;
for(left=0, *s++=x, j=N; --j;
*s++ = (x*=69069U) & 0xFFFFFFFFU);
*s++ = (x*=69069UL) & 0xFFFFFFFFUL);
}
static long rand_reload(void)
static int rand_reload(void)
{
unsigned long *p0=state, *p2=state+2, *pM=state+M, s0, s1;
int j;
if(left < -1)
srand(4357U);
srand(4357UL);
left=N-1, next=state+1;
for(s0=state[0], s1=state[1], j=N-M+1; --j; s0=s1, s1=*p2++)
*p0++ = *pM++ ^ (mixBits(s0, s1) >> 1) ^ (loBit(s1) ? K : 0U);
*p0++ = *pM++ ^ (mixBits(s0, s1) >> 1) ^ (loBit(s1) ? K : 0UL);
for(pM=state, j=M; --j; s0=s1, s1=*p2++)
*p0++ = *pM++ ^ (mixBits(s0, s1) >> 1) ^ (loBit(s1) ? K : 0U);
*p0++ = *pM++ ^ (mixBits(s0, s1) >> 1) ^ (loBit(s1) ? K : 0UL);
s1=state[0], *p0 = *pM ^ (mixBits(s0, s1) >> 1) ^ (loBit(s1) ? K : 0U);
s1=state[0], *p0 = *pM ^ (mixBits(s0, s1) >> 1) ^ (loBit(s1) ? K : 0UL);
s1 ^= (s1 >> 11);
s1 ^= (s1 << 7) & 0x9D2C5680U;
s1 ^= (s1 << 15) & 0xEFC60000U;
s1 ^= (s1 << 7) & 0x9D2C5680UL;
s1 ^= (s1 << 15) & 0xEFC60000UL;
return (long)s1 ^ (s1 >> 18);
}
long rand(void)
int rand(void)
{
unsigned long y;
@ -148,10 +148,12 @@ long rand(void)
else {
y = *next++;
y ^= (y >> 11);
y ^= (y << 7) & 0x9D2C5680U;
y ^= (y << 15) & 0xEFC60000U;
y ^= (y << 7) & 0x9D2C5680UL;
y ^= (y << 15) & 0xEFC60000UL;
y ^= (y >> 18);
}
return (y & 0xfffffffe) >> 1; /* 31-bit limit by Björn Stenberg*/
return ((unsigned int)y) >> 1;
/* 31-bit limit by Björn Stenberg*/
/* 16-bit architectures compatibility by Jean-Philippe Bernardy */
}

6
firmware/include/stdlib.h
View File

@ -30,10 +30,10 @@ void *calloc (size_t nmemb, size_t size);
void free(void *);
void *realloc(void *, size_t);
#define RAND_MAX 0x7fffffff
#define RAND_MAX INT_MAX
void srand(unsigned long seed);
long rand(void);
void srand(unsigned int seed);
int rand(void);
#define abs(x) ((x)>0?(x):-(x))