kernel/fs/zfs/lua/lcompat.c

   1 /*
   2  * Copyright (c) 2016 by Delphix. All rights reserved.
   3  */
   4
   5 #include "lua.h"
   6
   7 #include <sys/zfs_context.h>
   8
   9 ssize_t
  10 lcompat_sprintf(char *buf, const char *fmt, ...)
  11 {
  12         ssize_t res;
  13         va_list args;
  14
  15         va_start(args, fmt);
  16         res = vsnprintf(buf, INT_MAX, fmt, args);
  17         va_end(args);
  18
  19         return (res);
  20 }
  21
  22 int64_t
  23 lcompat_strtoll(const char *str, char **ptr)
  24 {
  25         int base;
  26         const char *cp;
  27         int digits;
  28         int64_t value;
  29         boolean_t is_negative;
  30
  31         cp = str;
  32         while (*cp == ' ' || *cp == '\t' || *cp == '\n') {
  33                 cp++;
  34         }
  35         is_negative = (*cp == '-');
  36         if (is_negative) {
  37                 cp++;
  38         }
  39         base = 10;
  40
  41         if (*cp == '0') {
  42                 base = 8;
  43                 cp++;
  44                 if (*cp == 'x' || *cp == 'X') {
  45                         base = 16;
  46                         cp++;
  47                 }
  48         }
  49
  50         value = 0;
  51         for (; *cp != '\0'; cp++) {
  52                 if (*cp >= '0' && *cp <= '9') {
  53                         digits = *cp - '0';
  54                 } else if (*cp >= 'a' && *cp <= 'f') {
  55                         digits = *cp - 'a' + 10;
  56                 } else if (*cp >= 'A' && *cp <= 'F') {
  57                         digits = *cp - 'A' + 10;
  58                 } else {
  59                         break;
  60                 }
  61                 if (digits >= base) {
  62                         break;
  63                 }
  64                 value = (value * base) + digits;
  65         }
  66
  67         if (ptr != NULL) {
  68                 *ptr = (char *)cp;
  69         }
  70         if (is_negative) {
  71                 value = -value;
  72         }
  73         return (value);
  74 }
  75
  76 int64_t
  77 lcompat_pow(int64_t x, int64_t y)
  78 {
  79         int64_t result = 1;
  80         if (y < 0)
  81                 return (0);
  82
  83         while (y) {
  84                 if (y & 1)
  85                         result *= x;
  86                 y >>= 1;
  87                 x *= x;
  88         }
  89         return (result);
  90 }
  91
  92 int
  93 lcompat_hashnum(int64_t x)
  94 {
  95         x = (~x) + (x << 18);
  96         x = x ^ (x >> 31);
  97         x = x * 21;
  98         x = x ^ (x >> 11);
  99         x = x + (x << 6);
 100         x = x ^ (x >> 22);
 101         return ((int)x);
 102 }