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
get_option(char ** str,int * pint)34 int 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
get_options(char * str,int nints,int * ints)67 char *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
memparse(char * ptr,char ** retptr)96 unsigned 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
118 EXPORT_SYMBOL(memparse);
119 EXPORT_SYMBOL(get_option);
120 EXPORT_SYMBOL(get_options);
121