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