android_kernel_samsung_msm8976/include/linux/string_helpers.h
Andy Shevchenko 16c7fa0582 lib/string_helpers: introduce generic string_unescape
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>
2013-04-30 17:04:03 -07:00

74 lines
2.1 KiB
C

#ifndef _LINUX_STRING_HELPERS_H_
#define _LINUX_STRING_HELPERS_H_
#include <linux/types.h>
/* Descriptions of the types of units to
* print in */
enum string_size_units {
STRING_UNITS_10, /* use powers of 10^3 (standard SI) */
STRING_UNITS_2, /* use binary powers of 2^10 */
};
int string_get_size(u64 size, enum string_size_units units,
char *buf, int len);
#define UNESCAPE_SPACE 0x01
#define UNESCAPE_OCTAL 0x02
#define UNESCAPE_HEX 0x04
#define UNESCAPE_SPECIAL 0x08
#define UNESCAPE_ANY \
(UNESCAPE_SPACE | UNESCAPE_OCTAL | UNESCAPE_HEX | UNESCAPE_SPECIAL)
/**
* string_unescape - unquote characters in the given string
* @src: source buffer (escaped)
* @dst: destination buffer (unescaped)
* @size: size of the destination buffer (0 to unlimit)
* @flags: combination of the flags (bitwise OR):
* %UNESCAPE_SPACE:
* '\f' - form feed
* '\n' - new line
* '\r' - carriage return
* '\t' - horizontal tab
* '\v' - vertical tab
* %UNESCAPE_OCTAL:
* '\NNN' - byte with octal value NNN (1 to 3 digits)
* %UNESCAPE_HEX:
* '\xHH' - byte with hexadecimal value HH (1 to 2 digits)
* %UNESCAPE_SPECIAL:
* '\"' - double quote
* '\\' - backslash
* '\a' - alert (BEL)
* '\e' - escape
* %UNESCAPE_ANY:
* all previous together
*
* Returns amount of characters processed to the destination buffer excluding
* trailing '\0'.
*
* Because the size of the output will be the same as or less than the size of
* the input, the transformation may be performed in place.
*
* Caller must provide valid source and destination pointers. Be aware that
* destination buffer will always be NULL-terminated. Source string must be
* NULL-terminated as well.
*/
int string_unescape(char *src, char *dst, size_t size, unsigned int flags);
static inline int string_unescape_inplace(char *buf, unsigned int flags)
{
return string_unescape(buf, buf, 0, flags);
}
static inline int string_unescape_any(char *src, char *dst, size_t size)
{
return string_unescape(src, dst, size, UNESCAPE_ANY);
}
static inline int string_unescape_any_inplace(char *buf)
{
return string_unescape_any(buf, buf, 0);
}
#endif