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#ifndef _STRINGS_H
#define _STRINGS_H
/** @file
*
* String functions
*
*/
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
#include <string.h>
#include <bits/strings.h>
/**
* Find first (i.e. least significant) set bit
*
* @v x Value
* @ret lsb Least significant bit set in value (LSB=1), or zero
*/
static inline __attribute__ (( always_inline )) int
__constant_ffsll ( unsigned long long x ) {
int r = 0;
if ( ! ( x & 0x00000000ffffffffULL ) ) {
x >>= 32;
r += 32;
}
if ( ! ( x & 0x0000ffffUL ) ) {
x >>= 16;
r += 16;
}
if ( ! ( x & 0x00ff ) ) {
x >>= 8;
r += 8;
}
if ( ! ( x & 0x0f ) ) {
x >>= 4;
r += 4;
}
if ( ! ( x & 0x3 ) ) {
x >>= 2;
r += 2;
}
if ( ! ( x & 0x1 ) ) {
x >>= 1;
r += 1;
}
return ( x ? ( r + 1 ) : 0 );
}
/**
* Find first (i.e. least significant) set bit
*
* @v x Value
* @ret lsb Least significant bit set in value (LSB=1), or zero
*/
static inline __attribute__ (( always_inline )) int
__constant_ffsl ( unsigned long x ) {
return __constant_ffsll ( x );
}
/**
* Find last (i.e. most significant) set bit
*
* @v x Value
* @ret msb Most significant bit set in value (LSB=1), or zero
*/
static inline __attribute__ (( always_inline )) int
__constant_flsll ( unsigned long long x ) {
int r = 0;
if ( x & 0xffffffff00000000ULL ) {
x >>= 32;
r += 32;
}
if ( x & 0xffff0000UL ) {
x >>= 16;
r += 16;
}
if ( x & 0xff00 ) {
x >>= 8;
r += 8;
}
if ( x & 0xf0 ) {
x >>= 4;
r += 4;
}
if ( x & 0xc ) {
x >>= 2;
r += 2;
}
if ( x & 0x2 ) {
x >>= 1;
r += 1;
}
return ( x ? ( r + 1 ) : 0 );
}
/**
* Find last (i.e. most significant) set bit
*
* @v x Value
* @ret msb Most significant bit set in value (LSB=1), or zero
*/
static inline __attribute__ (( always_inline )) int
__constant_flsl ( unsigned long x ) {
return __constant_flsll ( x );
}
int __ffsll ( long long x );
int __ffsl ( long x );
int __flsll ( long long x );
int __flsl ( long x );
/**
* Find first (i.e. least significant) set bit
*
* @v x Value
* @ret lsb Least significant bit set in value (LSB=1), or zero
*/
#define ffsll( x ) \
( __builtin_constant_p ( x ) ? __constant_ffsll ( x ) : __ffsll ( x ) )
/**
* Find first (i.e. least significant) set bit
*
* @v x Value
* @ret lsb Least significant bit set in value (LSB=1), or zero
*/
#define ffsl( x ) \
( __builtin_constant_p ( x ) ? __constant_ffsl ( x ) : __ffsl ( x ) )
/**
* Find first (i.e. least significant) set bit
*
* @v x Value
* @ret lsb Least significant bit set in value (LSB=1), or zero
*/
#define ffs( x ) ffsl ( x )
/**
* Find last (i.e. most significant) set bit
*
* @v x Value
* @ret msb Most significant bit set in value (LSB=1), or zero
*/
#define flsll( x ) \
( __builtin_constant_p ( x ) ? __constant_flsll ( x ) : __flsll ( x ) )
/**
* Find last (i.e. most significant) set bit
*
* @v x Value
* @ret msb Most significant bit set in value (LSB=1), or zero
*/
#define flsl( x ) \
( __builtin_constant_p ( x ) ? __constant_flsl ( x ) : __flsl ( x ) )
/**
* Find last (i.e. most significant) set bit
*
* @v x Value
* @ret msb Most significant bit set in value (LSB=1), or zero
*/
#define fls( x ) flsl ( x )
/**
* Copy memory
*
* @v src Source
* @v dest Destination
* @v len Length
*/
static inline __attribute__ (( always_inline )) void
bcopy ( const void *src, void *dest, size_t len ) {
memmove ( dest, src, len );
}
/**
* Zero memory
*
* @v dest Destination
* @v len Length
*/
static inline __attribute__ (( always_inline )) void
bzero ( void *dest, size_t len ) {
memset ( dest, 0, len );
}
int __pure strcasecmp ( const char *first, const char *second ) __nonnull;
#endif /* _STRINGS_H */
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