Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * Helper function for splitting a string into an argv-like array.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) #include <linux/ctype.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <linux/string.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <linux/slab.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/export.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) static int count_argc(const char *str)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 	int count = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) 	bool was_space;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 	for (was_space = true; *str; str++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 		if (isspace(*str)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 			was_space = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 		} else if (was_space) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 			was_space = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 			count++;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 	return count;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30)  * argv_free - free an argv
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31)  * @argv - the argument vector to be freed
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)  * Frees an argv and the strings it points to.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) void argv_free(char **argv)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 	argv--;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 	kfree(argv[0]);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 	kfree(argv);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) EXPORT_SYMBOL(argv_free);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)  * argv_split - split a string at whitespace, returning an argv
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45)  * @gfp: the GFP mask used to allocate memory
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46)  * @str: the string to be split
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)  * @argcp: returned argument count
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49)  * Returns an array of pointers to strings which are split out from
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50)  * @str.  This is performed by strictly splitting on white-space; no
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51)  * quote processing is performed.  Multiple whitespace characters are
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52)  * considered to be a single argument separator.  The returned array
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53)  * is always NULL-terminated.  Returns NULL on memory allocation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54)  * failure.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55)  *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56)  * The source string at `str' may be undergoing concurrent alteration via
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57)  * userspace sysctl activity (at least).  The argv_split() implementation
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58)  * attempts to handle this gracefully by taking a local copy to work on.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) char **argv_split(gfp_t gfp, const char *str, int *argcp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 	char *argv_str;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 	bool was_space;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 	char **argv, **argv_ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 	int argc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 	argv_str = kstrndup(str, KMALLOC_MAX_SIZE - 1, gfp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 	if (!argv_str)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 		return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 	argc = count_argc(argv_str);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 	argv = kmalloc_array(argc + 2, sizeof(*argv), gfp);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 	if (!argv) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 		kfree(argv_str);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) 		return NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) 	*argv = argv_str;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) 	argv_ret = ++argv;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) 	for (was_space = true; *argv_str; argv_str++) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) 		if (isspace(*argv_str)) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) 			was_space = true;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) 			*argv_str = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) 		} else if (was_space) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) 			was_space = false;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) 			*argv++ = argv_str;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) 	*argv = NULL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) 	if (argcp)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) 		*argcp = argc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) 	return argv_ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) EXPORT_SYMBOL(argv_split);