*/
+#include <string.h>
#include "rand.h"
#include "../hash.h"
-struct frand_state __fio_rand_state;
-
static inline int __seed(unsigned int x, unsigned int m)
{
return (x < m) ? x + m : x;
}
+static void __init_rand(struct frand_state *state, unsigned int seed)
+{
+ int cranks = 6;
+
+#define LCG(x, seed) ((x) * 69069 ^ (seed))
+
+ state->s1 = __seed(LCG((2^31) + (2^17) + (2^7), seed), 1);
+ state->s2 = __seed(LCG(state->s1, seed), 7);
+ state->s3 = __seed(LCG(state->s2, seed), 15);
+
+ while (cranks--)
+ __rand(state);
+}
+
void init_rand(struct frand_state *state)
{
-#define LCG(x) ((x) * 69069) /* super-duper LCG */
-
- state->s1 = __seed(LCG((2^31) + (2^17) + (2^7)), 1);
- state->s2 = __seed(LCG(state->s1), 7);
- state->s3 = __seed(LCG(state->s2), 15);
-
- __rand(state);
- __rand(state);
- __rand(state);
- __rand(state);
- __rand(state);
- __rand(state);
+ __init_rand(state, 1);
}
-void fill_random_buf(void *buf, unsigned int len)
+void init_rand_seed(struct frand_state *state, unsigned int seed)
{
- unsigned long r = __rand(&__fio_rand_state);
- long *ptr = buf;
+ __init_rand(state, seed);
+}
- if (sizeof(int) != sizeof(*ptr))
- r *= (unsigned long) __rand(&__fio_rand_state);
+void __fill_random_buf(void *buf, unsigned int len, unsigned long seed)
+{
+ long *ptr = buf;
while ((void *) ptr - buf < len) {
- *ptr = r;
+ *ptr = seed;
ptr++;
- r *= GOLDEN_RATIO_PRIME;
- r >>= 3;
+ seed *= GOLDEN_RATIO_PRIME;
+ seed >>= 3;
+ }
+}
+
+unsigned long fill_random_buf(struct frand_state *fs, void *buf,
+ unsigned int len)
+{
+ unsigned long r = __rand(fs);
+
+ if (sizeof(int) != sizeof(long *))
+ r *= (unsigned long) __rand(fs);
+
+ __fill_random_buf(buf, len, r);
+ return r;
+}
+
+unsigned long fill_random_buf_percentage(struct frand_state *fs, void *buf,
+ unsigned int percentage,
+ unsigned int segment, unsigned int len)
+{
+ unsigned long r = __rand(fs);
+ unsigned int this_len;
+
+ if (percentage == 100) {
+ memset(buf, 0, len);
+ return 0;
}
+
+ if (segment > len)
+ segment = len;
+
+ if (sizeof(int) != sizeof(long *))
+ r *= (unsigned long) __rand(fs);
+
+ while (len) {
+ /*
+ * Fill random chunk
+ */
+ this_len = (segment * (100 - percentage)) / 100;
+ if (this_len > len)
+ this_len = len;
+
+ __fill_random_buf(buf, this_len, r);
+
+ len -= this_len;
+ buf += this_len;
+
+ if (this_len > len)
+ this_len = len;
+
+ memset(buf, 0, this_len);
+ len -= this_len;
+ buf += this_len;
+ }
+
+ return r;
}