arch/s390/boot/string.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <linux/ctype.h>
   3 #include <linux/kernel.h>
   4 #include <linux/errno.h>
   5 #include "../lib/string.c"
   6
   7 int strncmp(const char *cs, const char *ct, size_t count)
   8 {
   9         unsigned char c1, c2;
  10
  11         while (count) {
  12                 c1 = *cs++;
  13                 c2 = *ct++;
  14                 if (c1 != c2)
  15                         return c1 < c2 ? -1 : 1;
  16                 if (!c1)
  17                         break;
  18                 count--;
  19         }
  20         return 0;
  21 }
  22
  23 char *skip_spaces(const char *str)
  24 {
  25         while (isspace(*str))
  26                 ++str;
  27         return (char *)str;
  28 }
  29
  30 char *strim(char *s)
  31 {
  32         size_t size;
  33         char *end;
  34
  35         size = strlen(s);
  36         if (!size)
  37                 return s;
  38
  39         end = s + size - 1;
  40         while (end >= s && isspace(*end))
  41                 end--;
  42         *(end + 1) = '\0';
  43
  44         return skip_spaces(s);
  45 }
  46
  47 /* Works only for digits and letters, but small and fast */
  48 #define TOLOWER(x) ((x) | 0x20)
  49
  50 static unsigned int simple_guess_base(const char *cp)
  51 {
  52         if (cp[0] == '0') {
  53                 if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2]))
  54                         return 16;
  55                 else
  56                         return 8;
  57         } else {
  58                 return 10;
  59         }
  60 }
  61
  62 /**
  63  * simple_strtoull - convert a string to an unsigned long long
  64  * @cp: The start of the string
  65  * @endp: A pointer to the end of the parsed string will be placed here
  66  * @base: The number base to use
  67  */
  68
  69 unsigned long long simple_strtoull(const char *cp, char **endp,
  70                                    unsigned int base)
  71 {
  72         unsigned long long result = 0;
  73
  74         if (!base)
  75                 base = simple_guess_base(cp);
  76
  77         if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x')
  78                 cp += 2;
  79
  80         while (isxdigit(*cp)) {
  81                 unsigned int value;
  82
  83                 value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10;
  84                 if (value >= base)
  85                         break;
  86                 result = result * base + value;
  87                 cp++;
  88         }
  89         if (endp)
  90                 *endp = (char *)cp;
  91
  92         return result;
  93 }
  94
  95 long simple_strtol(const char *cp, char **endp, unsigned int base)
  96 {
  97         if (*cp == '-')
  98                 return -simple_strtoull(cp + 1, endp, base);
  99
 100         return simple_strtoull(cp, endp, base);
 101 }
 102
 103 int kstrtobool(const char *s, bool *res)
 104 {
 105         if (!s)
 106                 return -EINVAL;
 107
 108         switch (s[0]) {
 109         case 'y':
 110         case 'Y':
 111         case '1':
 112                 *res = true;
 113                 return 0;
 114         case 'n':
 115         case 'N':
 116         case '0':
 117                 *res = false;
 118                 return 0;
 119         case 'o':
 120         case 'O':
 121                 switch (s[1]) {
 122                 case 'n':
 123                 case 'N':
 124                         *res = true;
 125                         return 0;
 126                 case 'f':
 127                 case 'F':
 128                         *res = false;
 129                         return 0;
 130                 default:
 131                         break;
 132                 }
 133         default:
 134                 break;
 135         }
 136
 137         return -EINVAL;
 138 }