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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /lib/cmdline.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | lib/cmdline.c | 275 |
1 files changed, 275 insertions, 0 deletions
diff --git a/lib/cmdline.c b/lib/cmdline.c new file mode 100644 index 0000000000..90ed997d95 --- /dev/null +++ b/lib/cmdline.c @@ -0,0 +1,275 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 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. + * + * GNU Indent formatting options for this file: -kr -i8 -npsl -pcs + */ + +#include <linux/export.h> +#include <linux/kernel.h> +#include <linux/string.h> +#include <linux/ctype.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 n) +{ + int x, inc_counter, upper_range; + + (*str)++; + upper_range = simple_strtol((*str), NULL, 0); + inc_counter = upper_range - *pint; + for (x = *pint; n && x < upper_range; x++, n--) + *pint++ = x; + return inc_counter; +} + +/** + * get_option - Parse integer from an option string + * @str: option string + * @pint: (optional output) integer value parsed from @str + * + * Read an int from an option string; if available accept a subsequent + * comma as well. + * + * When @pint is NULL the function can be used as a validator of + * the current option in the string. + * + * 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 + * + * Leading hyphen without integer is no integer case, but we consume it + * for the sake of simplification. + */ + +int get_option(char **str, int *pint) +{ + char *cur = *str; + int value; + + if (!cur || !(*cur)) + return 0; + if (*cur == '-') + value = -simple_strtoull(++cur, str, 0); + else + value = simple_strtoull(cur, str, 0); + if (pint) + *pint = value; + 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 (must have room for at least one element) + * + * 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. + * + * When @nints is 0, the function just validates the given @str and + * returns the amount of parseable integers as described below. + * + * Returns: + * + * The first element is filled by the number of collected integers + * in the range. The rest is what was parsed from the @str. + * + * 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) +{ + bool validate = (nints == 0); + int res, i = 1; + + while (i < nints || validate) { + int *pint = validate ? ints : ints + i; + + res = get_option((char **)&str, pint); + if (res == 0) + break; + if (res == 3) { + int n = validate ? 0 : nints - i; + int range_nums; + + range_nums = get_range((char **)&str, pint, n); + 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; + fallthrough; + case 'P': + case 'p': + ret <<= 10; + fallthrough; + case 'T': + case 't': + ret <<= 10; + fallthrough; + case 'G': + case 'g': + ret <<= 10; + fallthrough; + case 'M': + case 'm': + ret <<= 10; + fallthrough; + case 'K': + case 'k': + ret <<= 10; + endptr++; + fallthrough; + 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; +} + +/* + * Parse a string to get a param value pair. + * You can use " around spaces, but can't escape ". + * Hyphens and underscores equivalent in parameter names. + */ +char *next_arg(char *args, char **param, char **val) +{ + unsigned int i, equals = 0; + int in_quote = 0, quoted = 0; + + if (*args == '"') { + args++; + in_quote = 1; + quoted = 1; + } + + for (i = 0; args[i]; i++) { + if (isspace(args[i]) && !in_quote) + break; + if (equals == 0) { + if (args[i] == '=') + equals = i; + } + if (args[i] == '"') + in_quote = !in_quote; + } + + *param = args; + if (!equals) + *val = NULL; + else { + args[equals] = '\0'; + *val = args + equals + 1; + + /* Don't include quotes in value. */ + if (**val == '"') { + (*val)++; + if (args[i-1] == '"') + args[i-1] = '\0'; + } + } + if (quoted && i > 0 && args[i-1] == '"') + args[i-1] = '\0'; + + if (args[i]) { + args[i] = '\0'; + args += i + 1; + } else + args += i; + + /* Chew up trailing spaces. */ + return skip_spaces(args); +} +EXPORT_SYMBOL(next_arg); |