forked from mirrors/linux
		
	There are several places in kernel where modules unescapes input to convert C-Style Escape Sequences into byte codes. The patch provides generic implementation of such approach. Test cases are also included into the patch. [akpm@linux-foundation.org: clarify comment] [akpm@linux-foundation.org: export get_random_int() to modules] Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Samuel Thibault <samuel.thibault@ens-lyon.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Jason Baron <jbaron@redhat.com> Cc: Alexander Viro <viro@zeniv.linux.org.uk> Cc: William Hubbs <w.d.hubbs@gmail.com> Cc: Chris Brannon <chris@the-brannons.com> Cc: Kirk Reiser <kirk@braille.uwo.ca> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
		
			
				
	
	
		
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			74 lines
		
	
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
#ifndef _LINUX_STRING_HELPERS_H_
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#define _LINUX_STRING_HELPERS_H_
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#include <linux/types.h>
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/* Descriptions of the types of units to
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 * print in */
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enum string_size_units {
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	STRING_UNITS_10,	/* use powers of 10^3 (standard SI) */
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	STRING_UNITS_2,		/* use binary powers of 2^10 */
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};
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int string_get_size(u64 size, enum string_size_units units,
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		    char *buf, int len);
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#define UNESCAPE_SPACE		0x01
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#define UNESCAPE_OCTAL		0x02
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#define UNESCAPE_HEX		0x04
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#define UNESCAPE_SPECIAL	0x08
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#define UNESCAPE_ANY		\
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	(UNESCAPE_SPACE | UNESCAPE_OCTAL | UNESCAPE_HEX | UNESCAPE_SPECIAL)
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/**
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 * string_unescape - unquote characters in the given string
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 * @src:	source buffer (escaped)
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 * @dst:	destination buffer (unescaped)
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 * @size:	size of the destination buffer (0 to unlimit)
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 * @flags:	combination of the flags (bitwise OR):
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 *	%UNESCAPE_SPACE:
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 *		'\f' - form feed
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 *		'\n' - new line
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 *		'\r' - carriage return
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 *		'\t' - horizontal tab
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 *		'\v' - vertical tab
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 *	%UNESCAPE_OCTAL:
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 *		'\NNN' - byte with octal value NNN (1 to 3 digits)
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 *	%UNESCAPE_HEX:
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 *		'\xHH' - byte with hexadecimal value HH (1 to 2 digits)
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 *	%UNESCAPE_SPECIAL:
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 *		'\"' - double quote
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 *		'\\' - backslash
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 *		'\a' - alert (BEL)
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 *		'\e' - escape
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 *	%UNESCAPE_ANY:
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 *		all previous together
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 *
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 * Returns amount of characters processed to the destination buffer excluding
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 * trailing '\0'.
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 *
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 * Because the size of the output will be the same as or less than the size of
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 * the input, the transformation may be performed in place.
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 *
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 * Caller must provide valid source and destination pointers. Be aware that
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 * destination buffer will always be NULL-terminated. Source string must be
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 * NULL-terminated as well.
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 */
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int string_unescape(char *src, char *dst, size_t size, unsigned int flags);
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static inline int string_unescape_inplace(char *buf, unsigned int flags)
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{
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	return string_unescape(buf, buf, 0, flags);
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}
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static inline int string_unescape_any(char *src, char *dst, size_t size)
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{
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	return string_unescape(src, dst, size, UNESCAPE_ANY);
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}
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static inline int string_unescape_any_inplace(char *buf)
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{
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	return string_unescape_any(buf, buf, 0);
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}
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#endif
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