Skip to content

HTTPS clone URL

Subversion checkout URL

You can clone with
or
.
Download ZIP
Fetching contributors…

Cannot retrieve contributors at this time

192 lines (170 sloc) 4.175 kb
/*
* linux/lib/cmdline.c
* Helper functions generally used for parsing kernel command line
* and module options.
*
* Code and copyrights come from init/main.c and arch/i386/kernel/setup.c.
*
* This source code is licensed under the GNU General Public License,
* Version 2. See the file COPYING for more details.
*
* GNU Indent formatting options for this file: -kr -i8 -npsl -pcs
*
*/
#include <linux/export.h>
#include <linux/kernel.h>
#include <linux/string.h>
/*
* If a hyphen was found in get_option, this will handle the
* range of numbers, M-N. This will expand the range and insert
* the values[M, M+1, ..., N] into the ints array in get_options.
*/
static int get_range(char **str, int *pint)
{
int x, inc_counter, upper_range;
(*str)++;
upper_range = simple_strtol((*str), NULL, 0);
inc_counter = upper_range - *pint;
for (x = *pint; x < upper_range; x++)
*pint++ = x;
return inc_counter;
}
/**
* get_option - Parse integer from an option string
* @str: option string
* @pint: (output) integer value parsed from @str
*
* Read an int from an option string; if available accept a subsequent
* comma as well.
*
* Return values:
* 0 - no int in string
* 1 - int found, no subsequent comma
* 2 - int found including a subsequent comma
* 3 - hyphen found to denote a range
*/
int get_option(char **str, int *pint)
{
char *cur = *str;
if (!cur || !(*cur))
return 0;
*pint = simple_strtol(cur, str, 0);
if (cur == *str)
return 0;
if (**str == ',') {
(*str)++;
return 2;
}
if (**str == '-')
return 3;
return 1;
}
EXPORT_SYMBOL(get_option);
/**
* get_options - Parse a string into a list of integers
* @str: String to be parsed
* @nints: size of integer array
* @ints: integer array
*
* This function parses a string containing a comma-separated
* list of integers, a hyphen-separated range of _positive_ integers,
* or a combination of both. The parse halts when the array is
* full, or when no more numbers can be retrieved from the
* string.
*
* Return value is the character in the string which caused
* the parse to end (typically a null terminator, if @str is
* completely parseable).
*/
char *get_options(const char *str, int nints, int *ints)
{
int res, i = 1;
while (i < nints) {
res = get_option((char **)&str, ints + i);
if (res == 0)
break;
if (res == 3) {
int range_nums;
range_nums = get_range((char **)&str, ints + i);
if (range_nums < 0)
break;
/*
* Decrement the result by one to leave out the
* last number in the range. The next iteration
* will handle the upper number in the range
*/
i += (range_nums - 1);
}
i++;
if (res == 1)
break;
}
ints[0] = i - 1;
return (char *)str;
}
EXPORT_SYMBOL(get_options);
/**
* memparse - parse a string with mem suffixes into a number
* @ptr: Where parse begins
* @retptr: (output) Optional pointer to next char after parse completes
*
* Parses a string into a number. The number stored at @ptr is
* potentially suffixed with K, M, G, T, P, E.
*/
unsigned long long memparse(const char *ptr, char **retptr)
{
char *endptr; /* local pointer to end of parsed string */
unsigned long long ret = simple_strtoull(ptr, &endptr, 0);
switch (*endptr) {
case 'E':
case 'e':
ret <<= 10;
case 'P':
case 'p':
ret <<= 10;
case 'T':
case 't':
ret <<= 10;
case 'G':
case 'g':
ret <<= 10;
case 'M':
case 'm':
ret <<= 10;
case 'K':
case 'k':
ret <<= 10;
endptr++;
default:
break;
}
if (retptr)
*retptr = endptr;
return ret;
}
EXPORT_SYMBOL(memparse);
/**
* parse_option_str - Parse a string and check an option is set or not
* @str: String to be parsed
* @option: option name
*
* This function parses a string containing a comma-separated list of
* strings like a=b,c.
*
* Return true if there's such option in the string, or return false.
*/
bool parse_option_str(const char *str, const char *option)
{
while (*str) {
if (!strncmp(str, option, strlen(option))) {
str += strlen(option);
if (!*str || *str == ',')
return true;
}
while (*str && *str != ',')
str++;
if (*str == ',')
str++;
}
return false;
}
Jump to Line
Something went wrong with that request. Please try again.