Catch more places where the callback should just return on parse/check
[fio.git] / lib / rand.c
index 7c6fed1fabbcc01f1803f00521d881a9c9662603..a79fb9c17c321a94e8e4bcfe030193003c80d93f 100644 (file)
@@ -33,6 +33,7 @@
 
 */
 
+#include <string.h>
 #include "rand.h"
 #include "../hash.h"
 
@@ -88,3 +89,45 @@ unsigned long fill_random_buf(struct frand_state *fs, void *buf,
        __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;
+}