1 // SPDX-License-Identifier: GPL-2.0-only
3  * Helpers for formatting and printing strings
23  * string_get_size - get the size in the specified units
116 		remainder -= 1000;  in string_get_size()
137  * parse_int_array_user - Split string into a sequence of integers
161 		ret = -ENOENT;  in parse_int_array_user()
167 		ret = -ENOMEM;  in parse_int_array_user()
211 	u8 num;  in unescape_octal()  local
216 	num = (*q++) & 7;  in unescape_octal()
217 	while (num < 32 && isodigit(*q) && (q - *src < 3)) {  in unescape_octal()
218 		num <<= 3;  in unescape_octal()
219 		num += (*q++) & 7;  in unescape_octal()
221 	*p = num;  in unescape_octal()
231 	u8 num;  in unescape_hex()  local
236 	num = digit = hex_to_bin(*q++);  in unescape_hex()
243 		num = (num << 4) | digit;  in unescape_hex()
245 	*p = num;  in unescape_hex()
277  * string_unescape - unquote characters in the given string
290  * destination buffer will always be NULL-terminated. Source string must be
291  * NULL-terminated as well.  The supported flags are::
294  *		'\f' - form feed
295  *		'\n' - new line
296  *		'\r' - carriage return
297  *		'\t' - horizontal tab
298  *		'\v' - vertical tab
300  *		'\NNN' - byte with octal value NNN (1 to 3 digits)
302  *		'\xHH' - byte with hexadecimal value HH (1 to 2 digits)
304  *		'\"' - double quote
305  *		'\\' - backslash
306  *		'\a' - alert (BEL)
307  *		'\e' - escape
319 	while (*src && --size) {  in string_unescape()
322 			size--;  in string_unescape()
346 	return out - dst;  in string_unescape()
490  * string_escape_mem - quote characters in the given memory buffer
496  * @only:	NULL-terminated string containing characters used to limit
506  *	   must go as-is to the output.
517  * destination buffer will not be NULL-terminated, thus caller have to append
521  *		'\f' - form feed
522  *		'\n' - new line
523  *		'\r' - carriage return
524  *		'\t' - horizontal tab
525  *		'\v' - vertical tab
527  *		'\"' - double quote
528  *		'\\' - backslash
529  *		'\a' - alert (BEL)
530  *		'\e' - escape
532  *		'\0' - null
534  *		'\NNN' - byte with octal value NNN (3 digits)
538  *		escape only non-printable characters, checked by isprint()
542  *		'\xHH' - byte with hexadecimal value HH (2 digits)
544  *		escape only non-ascii characters, checked by isascii()
546  *		escape only non-printable or non-ascii characters
574 	while (isz--) {  in string_escape_mem()
580 		 *	- the @only string is supplied and does not contain a  in string_escape_mem()
582 		 *	- the character is printable and ASCII, when @flags has  in string_escape_mem()
584 		 *	- the character is printable, when @flags has  in string_escape_mem()
586 		 *	- the character is ASCII, when @flags has  in string_escape_mem()
588 		 *	- the character doesn't fall into a class of symbols  in string_escape_mem()
632 	return p - dst;  in string_escape_mem()
664  * Returns allocated NULL-terminated string containing process
665  * command line, with inter-argument NULLs replaced with spaces,
677 	res = get_cmdline(task, buffer, PAGE_SIZE - 1);  in kstrdup_quotable_cmdline()
680 	/* Collapse trailing NULLs, leave res pointing to last non-NULL. */  in kstrdup_quotable_cmdline()
681 	while (--res >= 0 && buffer[res] == '\0')  in kstrdup_quotable_cmdline()
684 	/* Replace inter-argument NULLs. */  in kstrdup_quotable_cmdline()
697  * Returns allocated NULL-terminated string containing pathname,
740  * kasprintf_strarray - allocate and fill array of sequential strings
745  * Allocates and fills @n strings using pattern "%s-%zu", where prefix
749  * Returns array of strings or NULL when memory can't be allocated.
761 		names[i] = kasprintf(gfp, "%s-%zu", prefix, i);  in kasprintf_strarray()
773  * kfree_strarray - free a number of dynamically allocated strings contained
776  * @array: Dynamically allocated array of strings to free.
777  * @n: Number of strings (starting from the beginning of the array) to free.
779  * Passing a non-NULL @array and @n == 0 as well as NULL @array are valid
780  * use-cases. If @array is NULL, the function does nothing.
804 	kfree_strarray(array->array, array->n);  in devm_kfree_strarray()
813 		return ERR_PTR(-ENOMEM);  in devm_kasprintf_strarray()
815 	ptr->array = kasprintf_strarray(GFP_KERNEL, prefix, n);  in devm_kasprintf_strarray()
816 	if (!ptr->array) {  in devm_kasprintf_strarray()
818 		return ERR_PTR(-ENOMEM);  in devm_kasprintf_strarray()
821 	ptr->n = n;  in devm_kasprintf_strarray()
824 	return ptr->array;  in devm_kasprintf_strarray()
829  * strscpy_pad() - Copy a C-string into a sized buffer
836  * buffer is always %NUL terminated, unless it's zero-sized.
846  * * -E2BIG if count is 0 or @src was truncated.
853 	if (written < 0 || written == count - 1)  in strscpy_pad()
856 	memset(dest + written + 1, 0, count - written - 1);  in strscpy_pad()
863  * skip_spaces - Removes leading whitespace from @str.
866  * Returns a pointer to the first non-whitespace character in @str.
877  * strim - Removes leading and trailing whitespace from @s.
880  * Note that the first trailing whitespace is replaced with a %NUL-terminator
881  * in the given string @s. Returns a pointer to the first non-whitespace
893 	end = s + size - 1;  in strim()
895 		end--;  in strim()
903  * sysfs_streq - return true if strings are equal, modulo trailing newline
907  * This routine returns true iff two strings are equal, treating both
908  * NUL and newline-then-NUL as equivalent string terminations.  It's
909  * geared for use with sysfs input strings, which generally terminate
930  * match_string - matches given string in an array
931  * @array:	array of strings
932  * @n:		number of strings in the array or -1 for NULL terminated arrays
935  * This routine will look for a string in an array of strings up to the
936  * n-th element in the array or until the first NULL element.
938  * Historically the value of -1 for @n, was used to search in arrays that
944  * index of a @string in the @array if matches, or %-EINVAL otherwise.
959 	return -EINVAL;  in match_string()
964  * __sysfs_match_string - matches given string in an array
965  * @array: array of strings
966  * @n: number of strings in the array or -1 for NULL terminated arrays
969  * Returns index of @str in the @array or -EINVAL, just like match_string().
972  * This routine will look for a string in an array of strings up to the
973  * n-th element in the array or until the first NULL element.
975  * Historically the value of -1 for @n, was used to search in arrays that
993 	return -EINVAL;  in __sysfs_match_string()
998  * strreplace - Replace all occurrences of character in string.
1019  * memcpy_and_pad - Copy one buffer to another with padding
1031 		memset(dest + count, pad,  dest_len - count);  in memcpy_and_pad()
1039 /* These are placeholders for fortify compile-time warnings. */