programs/libc/stdlib.c

   1 /*
   2 Copyright (C) 2008  Mathias Gottschlag
   3
   4 Permission is hereby granted, free of charge, to any person obtaining a copy of
   5 this software and associated documentation files (the "Software"), to deal in the
   6 Software without restriction, including without limitation the rights to use,
   7 copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
   8 Software, and to permit persons to whom the Software is furnished to do so,
   9 subject to the following conditions:
  10
  11 The above copyright notice and this permission notice shall be included in all
  12 copies or substantial portions of the Software.
  13
  14 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
  15 INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
  16 PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
  17 HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  18 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  19 SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  20 */
  21
  22 #include <stdlib.h>
  23 #include <planlos/syscalls.h>
  24
  25 unsigned int errno;
  26
  27 void abort(void)
  28 {
  29         asm volatile("int $0x80" : : "a"(SYS_EXIT), "b"(-1));
  30 }
  31
  32 void *sbrk(int increment)
  33 {
  34         return 0;
  35 }
  36
  37 void exit(int value)
  38 {
  39         // TODO: Close files
  40         asm volatile("int $0x80" : : "a"(SYS_EXIT), "b"(value));
  41 }
  42
  43 int atoi(const char *str)
  44 {
  45         int number = 0;
  46         int negative = 0;
  47         if (*str == '-')
  48         {
  49                 str++;
  50                 negative = 1;
  51         }
  52         while (*str)
  53         {
  54                 if ((*str >= '0') && (*str <= '9'))
  55                 {
  56                         number = number * 10 + (*str - '0');
  57                         str++;
  58                 }
  59                 else
  60                 {
  61                         break;
  62                 }
  63         }
  64         return number;
  65 }
  66
  67 int abs(int n)
  68 {
  69         if (n < 0) return -n;
  70         return n;
  71 }
  72
  73 char *getenv(const char *name)
  74 {
  75         if (!strcmp(name, "TERM"))
  76         {
  77                 return "/dev/tty0";
  78         }
  79         else if (!strcmp(name, "TERMINFO"))
  80         {
  81                 return "/usr/lib/terminfo";
  82         }
  83         // TODO
  84         return "";
  85 }
  86
  87 static int strtol_is_digit(const char c, int base)
  88 {
  89         if ((c >= '0') && (c <= '9'))
  90         {
  91                 if (c - '0' < base)
  92                 {
  93                         return 1;
  94                 }
  95                 return 0;
  96         }
  97         else if ((c >= 'a') && (c <= 'z'))
  98         {
  99                 if (c - 'a' < base - 10)
 100                 {
 101                         return 1;
 102                 }
 103         }
 104         else if ((c >= 'A') && (c <= 'Z'))
 105         {
 106                 if (c - 'A' < base - 10)
 107                 {
 108                         return 1;
 109                 }
 110         }
 111         return 0;
 112 }
 113 static int strtol_get_digit(const char c, int base)
 114 {
 115         if ((c >= '0') && (c <= '9'))
 116         {
 117                 return c - '0';
 118         }
 119         else if ((c >= 'a') && (c <= 'z'))
 120         {
 121                 return c - 'a';
 122         }
 123         else if ((c >= 'A') && (c <= 'Z'))
 124         {
 125                 return c - 'A';
 126         }
 127         else return 0;
 128 }
 129
 130 long int strtol(const char *nptr, char **endptr, int base)
 131 {
 132         int negative = 0;
 133         if (*nptr == '-')
 134         {
 135                 negative = 1;
 136                 nptr++;
 137         }
 138
 139         long int number = 0;
 140
 141         while (strtol_is_digit(*nptr, base))
 142         {
 143                 number = number * base + strtol_get_digit(*nptr, base);
 144                 nptr++;
 145         }
 146         if (endptr) *endptr = (char*)nptr;
 147         if (negative) number = -number;
 148         return number;
 149 }
 150