3 * Helper functions generally used for parsing kernel command line
6 * Code and copyrights come from init/main.c and arch/i386/kernel/setup.c.
8 * This source code is licensed under the GNU General Public License,
9 * Version 2. See the file COPYING for more details.
11 * GNU Indent formatting options for this file: -kr -i8 -npsl -pcs
15 #include <linux/export.h>
16 #include <linux/kernel.h>
17 #include <linux/string.h>
20 * If a hyphen was found in get_option, this will handle the
21 * range of numbers, M-N. This will expand the range and insert
22 * the values[M, M+1, ..., N] into the ints array in get_options.
25 static int get_range(char **str, int *pint)
27 int x, inc_counter, upper_range;
30 upper_range = simple_strtol((*str), NULL, 0);
31 inc_counter = upper_range - *pint;
32 for (x = *pint; x < upper_range; x++)
38 * get_option - Parse integer from an option string
40 * @pint: (output) integer value parsed from @str
42 * Read an int from an option string; if available accept a subsequent
46 * 0 - no int in string
47 * 1 - int found, no subsequent comma
48 * 2 - int found including a subsequent comma
49 * 3 - hyphen found to denote a range
52 int get_option(char **str, int *pint)
58 *pint = simple_strtol(cur, str, 0);
70 EXPORT_SYMBOL(get_option);
73 * get_options - Parse a string into a list of integers
74 * @str: String to be parsed
75 * @nints: size of integer array
76 * @ints: integer array
78 * This function parses a string containing a comma-separated
79 * list of integers, a hyphen-separated range of _positive_ integers,
80 * or a combination of both. The parse halts when the array is
81 * full, or when no more numbers can be retrieved from the
84 * Return value is the character in the string which caused
85 * the parse to end (typically a null terminator, if @str is
86 * completely parseable).
89 char *get_options(const char *str, int nints, int *ints)
94 res = get_option((char **)&str, ints + i);
99 range_nums = get_range((char **)&str, ints + i);
103 * Decrement the result by one to leave out the
104 * last number in the range. The next iteration
105 * will handle the upper number in the range
107 i += (range_nums - 1);
116 EXPORT_SYMBOL(get_options);
119 * memparse - parse a string with mem suffixes into a number
120 * @ptr: Where parse begins
121 * @retptr: (output) Optional pointer to next char after parse completes
123 * Parses a string into a number. The number stored at @ptr is
124 * potentially suffixed with %K (for kilobytes, or 1024 bytes),
125 * %M (for megabytes, or 1048576 bytes), or %G (for gigabytes, or
126 * 1073741824). If the number is suffixed with K, M, or G, then
127 * the return value is the number multiplied by one kilobyte, one
128 * megabyte, or one gigabyte, respectively.
131 unsigned long long memparse(const char *ptr, char **retptr)
133 char *endptr; /* local pointer to end of parsed string */
135 unsigned long long ret = simple_strtoull(ptr, &endptr, 0);
157 EXPORT_SYMBOL(memparse);