linux-old/lib/cmdline.c
<<
>>
Prefs
   1/*
   2 * linux/lib/cmdline.c
   3 * Helper functions generally used for parsing kernel command line
   4 * and module options.
   5 *
   6 * Code and copyrights come from init/main.c and arch/i386/kernel/setup.c.
   7 *
   8 * This source code is licensed under the GNU General Public License,
   9 * Version 2.  See the file COPYING for more details.
  10 *
  11 * GNU Indent formatting options for this file: -kr -i8 -npsl -pcs
  12 *
  13 */
  14
  15#include <linux/module.h>
  16#include <linux/kernel.h>
  17#include <linux/string.h>
  18
  19
  20/**
  21 *      get_option - Parse integer from an option string
  22 *      @str: option string
  23 *      @pint: (output) integer value parsed from @str
  24 *
  25 *      Read an int from an option string; if available accept a subsequent
  26 *      comma as well.
  27 *
  28 *      Return values:
  29 *      0 : no int in string
  30 *      1 : int found, no subsequent comma
  31 *      2 : int found including a subsequent comma
  32 */
  33
  34int get_option (char **str, int *pint)
  35{
  36        char *cur = *str;
  37
  38        if (!cur || !(*cur))
  39                return 0;
  40        *pint = simple_strtol (cur, str, 0);
  41        if (cur == *str)
  42                return 0;
  43        if (**str == ',') {
  44                (*str)++;
  45                return 2;
  46        }
  47
  48        return 1;
  49}
  50
  51/**
  52 *      get_options - Parse a string into a list of integers
  53 *      @str: String to be parsed
  54 *      @nints: size of integer array
  55 *      @ints: integer array
  56 *
  57 *      This function parses a string containing a comma-separated
  58 *      list of integers.  The parse halts when the array is
  59 *      full, or when no more numbers can be retrieved from the
  60 *      string.
  61 *
  62 *      Return value is the character in the string which caused
  63 *      the parse to end (typically a null terminator, if @str is
  64 *      completely parseable).
  65 */
  66 
  67char *get_options (char *str, int nints, int *ints)
  68{
  69        int res, i = 1;
  70
  71        while (i < nints) {
  72                res = get_option (&str, ints + i);
  73                if (res == 0)
  74                        break;
  75                i++;
  76                if (res == 1)
  77                        break;
  78        }
  79        ints[0] = i - 1;
  80        return (str);
  81}
  82
  83/**
  84 *      memparse - parse a string with mem suffixes into a number
  85 *      @ptr: Where parse begins
  86 *      @retptr: (output) Pointer to next char after parse completes
  87 *
  88 *      Parses a string into a number.  The number stored at @ptr is
  89 *      potentially suffixed with %K (for kilobytes, or 1024 bytes),
  90 *      %M (for megabytes, or 1048576 bytes), or %G (for gigabytes, or
  91 *      1073741824).  If the number is suffixed with K, M, or G, then
  92 *      the return value is the number multiplied by one kilobyte, one
  93 *      megabyte, or one gigabyte, respectively.
  94 */
  95
  96unsigned long long memparse (char *ptr, char **retptr)
  97{
  98        unsigned long long ret = simple_strtoull (ptr, retptr, 0);
  99
 100        switch (**retptr) {
 101        case 'G':
 102        case 'g':
 103                ret <<= 10;
 104        case 'M':
 105        case 'm':
 106                ret <<= 10;
 107        case 'K':
 108        case 'k':
 109                ret <<= 10;
 110                (*retptr)++;
 111        default:
 112                break;
 113        }
 114        return ret;
 115}
 116
 117
 118EXPORT_SYMBOL(memparse);
 119EXPORT_SYMBOL(get_option);
 120EXPORT_SYMBOL(get_options);
 121
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.