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-rw-r--r--lib/cmdline.c120
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diff --git a/lib/cmdline.c b/lib/cmdline.c
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+/*
+ * 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/module.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+
+
+/**
+ * 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
+ */
+
+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;
+ }
+
+ return 1;
+}
+
+/**
+ * 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. 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;
+ i++;
+ if (res == 1)
+ break;
+ }
+ ints[0] = i - 1;
+ return (char *)str;
+}
+
+/**
+ * memparse - parse a string with mem suffixes into a number
+ * @ptr: Where parse begins
+ * @retptr: (output) Pointer to next char after parse completes
+ *
+ * Parses a string into a number. The number stored at @ptr is
+ * potentially suffixed with %K (for kilobytes, or 1024 bytes),
+ * %M (for megabytes, or 1048576 bytes), or %G (for gigabytes, or
+ * 1073741824). If the number is suffixed with K, M, or G, then
+ * the return value is the number multiplied by one kilobyte, one
+ * megabyte, or one gigabyte, respectively.
+ */
+
+unsigned long long memparse (char *ptr, char **retptr)
+{
+ unsigned long long ret = simple_strtoull (ptr, retptr, 0);
+
+ switch (**retptr) {
+ case 'G':
+ case 'g':
+ ret <<= 10;
+ case 'M':
+ case 'm':
+ ret <<= 10;
+ case 'K':
+ case 'k':
+ ret <<= 10;
+ (*retptr)++;
+ default:
+ break;
+ }
+ return ret;
+}
+
+
+EXPORT_SYMBOL(memparse);
+EXPORT_SYMBOL(get_option);
+EXPORT_SYMBOL(get_options);