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[libc] Rewrite string functions

Some of the C library string functions have an unknown provenance.
Reimplement all such functions to avoid potential licensing
uncertainty.

Remove the inline-assembler versions of strlen(), memswap(), and
strncmp(); these save a minimal amount of space (around 40 bytes in
total) and are not performance-critical.

Signed-off-by: Michael Brown <mcb30@ipxe.org>
This commit is contained in:
Michael Brown 2015-02-16 17:59:11 +00:00
parent b54167b8b6
commit 8ee39f7432
6 changed files with 400 additions and 432 deletions

View File

@ -104,87 +104,3 @@ void * __memmove ( void *dest, const void *src, size_t len ) {
return __memcpy_reverse ( dest, src, len );
}
}
/**
* Swap memory areas
*
* @v dest Destination address
* @v src Source address
* @v len Length
* @ret dest Destination address
*/
void * memswap ( void *dest, void *src, size_t len ) {
size_t discard_c;
int discard;
__asm__ __volatile__ ( "\n1:\n\t"
"dec %2\n\t"
"js 2f\n\t"
"movb (%0,%2), %b3\n\t"
"xchgb (%1,%2), %b3\n\t"
"movb %b3, (%0,%2)\n\t"
"jmp 1b\n\t"
"2:\n\t"
: "=r" ( src ), "=r" ( dest ),
"=&c" ( discard_c ), "=&q" ( discard )
: "0" ( src ), "1" ( dest ), "2" ( len )
: "memory" );
return dest;
}
/**
* Calculate length of string
*
* @v string String
* @ret len Length (excluding NUL)
*/
size_t strlen ( const char *string ) {
const char *discard_D;
size_t len_plus_one;
__asm__ __volatile__ ( "repne scasb\n\t"
"not %1\n\t"
: "=&D" ( discard_D ), "=&c" ( len_plus_one )
: "0" ( string ), "1" ( -1UL ), "a" ( 0 ) );
return ( len_plus_one - 1 );
}
/**
* Compare strings (up to a specified length)
*
* @v str1 First string
* @v str2 Second string
* @v len Maximum length
* @ret diff Difference
*/
int strncmp ( const char *str1, const char *str2, size_t len ) {
const void *discard_S;
const void *discard_D;
size_t discard_c;
int diff;
__asm__ __volatile__ ( "\n1:\n\t"
"dec %2\n\t"
"js 2f\n\t"
"lodsb\n\t"
"scasb\n\t"
"jne 3f\n\t"
"testb %b3, %b3\n\t"
"jnz 1b\n\t"
/* Equal */
"\n2:\n\t"
"xor %3, %3\n\t"
"jmp 4f\n\t"
/* Not equal; CF indicates difference */
"\n3:\n\t"
"sbb %3, %3\n\t"
"orb $1, %b3\n\t"
"\n4:\n\t"
: "=&S" ( discard_S ), "=&D" ( discard_D ),
"=&c" ( discard_c ), "=&a" ( diff )
: "0" ( str1 ), "1" ( str2 ), "2" ( len ) );
return diff;
}

View File

@ -28,8 +28,6 @@ FILE_LICENCE ( GPL2_OR_LATER );
*
*/
#define __HAVE_ARCH_MEMCPY
extern void * __memcpy ( void *dest, const void *src, size_t len );
extern void * __memcpy_reverse ( void *dest, const void *src, size_t len );
@ -169,8 +167,6 @@ memcpy ( void *dest, const void *src, size_t len ) {
}
}
#define __HAVE_ARCH_MEMMOVE
extern void * __memmove ( void *dest, const void *src, size_t len );
/**
@ -196,8 +192,6 @@ memmove ( void *dest, const void *src, size_t len ) {
}
}
#define __HAVE_ARCH_MEMSET
/**
* Fill memory region
*
@ -217,16 +211,4 @@ static inline void * memset ( void *dest, int fill, size_t len ) {
return dest;
}
#define __HAVE_ARCH_MEMSWAP
extern void * memswap ( void *dest, void *src, size_t len );
#define __HAVE_ARCH_STRNCMP
extern int strncmp ( const char *str1, const char *str2, size_t len );
#define __HAVE_ARCH_STRLEN
extern size_t strlen ( const char *string );
#endif /* X86_BITS_STRING_H */

View File

@ -1,353 +1,368 @@
/*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 2004 Tobias Lorenz
* Copyright (C) 2015 Michael Brown <mbrown@fensystems.co.uk>.
*
* string handling functions
* based on linux/lib/string.c
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301, USA.
*/
FILE_LICENCE ( GPL2_ONLY );
FILE_LICENCE ( GPL2_OR_LATER );
/*
* stupid library routines.. The optimized versions should generally be found
* as inline code in <asm-xx/string.h>
*
* These are buggy as well..
*
* * Fri Jun 25 1999, Ingo Oeser <ioe@informatik.tu-chemnitz.de>
* - Added strsep() which will replace strtok() soon (because strsep() is
* reentrant and should be faster). Use only strsep() in new code, please.
*/
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
/* *** FROM string.c *** */
#ifndef __HAVE_ARCH_STRCPY
/**
* strcpy - Copy a %NUL terminated string
* @dest: Where to copy the string to
* @src: Where to copy the string from
*/
char * strcpy(char * dest,const char *src)
{
char *tmp = dest;
while ((*dest++ = *src++) != '\0')
/* nothing */;
return tmp;
}
#endif
#ifndef __HAVE_ARCH_STRNCPY
/**
* strncpy - Copy a length-limited, %NUL-terminated string
* @dest: Where to copy the string to
* @src: Where to copy the string from
* @count: The maximum number of bytes to copy
/** @file
*
* String functions
*
* Note that unlike userspace strncpy, this does not %NUL-pad the buffer.
* However, the result is not %NUL-terminated if the source exceeds
* @count bytes.
*/
char * strncpy(char * dest,const char *src,size_t count)
{
char *tmp = dest;
while (count-- && (*dest++ = *src++) != '\0')
/* nothing */;
return tmp;
}
#endif
#ifndef __HAVE_ARCH_STRCAT
/**
* strcat - Append one %NUL-terminated string to another
* @dest: The string to be appended to
* @src: The string to append to it
* Fill memory region
*
* @v dest Destination region
* @v character Fill character
* @v len Length
* @ret dest Destination region
*/
char * strcat(char * dest, const char * src)
{
char *tmp = dest;
void * generic_memset ( void *dest, int character, size_t len ) {
uint8_t *dest_bytes = dest;
while (*dest)
dest++;
while ((*dest++ = *src++) != '\0')
;
return tmp;
while ( len-- )
*(dest_bytes++) = character;
return dest;
}
#endif
#ifndef __HAVE_ARCH_STRCMP
/**
* strcmp - Compare two strings
* @cs: One string
* @ct: Another string
* Copy memory region
*
* @v dest Destination region
* @v src Source region
* @v len Length
* @ret dest Destination region
*/
int strcmp(const char * cs,const char * ct)
{
register signed char __res;
void * generic_memcpy ( void *dest, const void *src, size_t len ) {
const uint8_t *src_bytes = src;
uint8_t *dest_bytes = dest;
while (1) {
if ((__res = *cs - *ct++) != 0 || !*cs++)
break;
while ( len-- )
*(dest_bytes++) = *(src_bytes++);
return dest;
}
/**
* Copy (possibly overlapping) memory region
*
* @v dest Destination region
* @v src Source region
* @v len Length
* @ret dest Destination region
*/
void * generic_memmove ( void *dest, const void *src, size_t len ) {
const uint8_t *src_bytes = ( src + len );
uint8_t *dest_bytes = ( dest + len );
if ( dest < src )
return memcpy ( dest, src, len );
while ( len-- )
*(--dest_bytes) = *(--src_bytes);
return dest;
}
/**
* Compare memory regions
*
* @v first First region
* @v second Second region
* @v len Length
* @ret diff Difference
*/
int memcmp ( const void *first, const void *second, size_t len ) {
const uint8_t *first_bytes = first;
const uint8_t *second_bytes = second;
int diff;
while ( len-- ) {
diff = ( *(second_bytes++) - *(first_bytes++) );
if ( diff )
return diff;
}
return __res;
return 0;
}
#endif
#ifndef __HAVE_ARCH_STRNCMP
/**
* strncmp - Compare two length-limited strings
* @cs: One string
* @ct: Another string
* @count: The maximum number of bytes to compare
* Find character within a memory region
*
* @v src Source region
* @v character Character to find
* @v len Length
* @ret found Found character, or NULL if not found
*/
int strncmp(const char * cs,const char * ct,size_t count)
{
register signed char __res = 0;
void * memchr ( const void *src, int character, size_t len ) {
const uint8_t *src_bytes = src;
while (count) {
if ((__res = *cs - *ct++) != 0 || !*cs++)
break;
count--;
for ( ; len-- ; src_bytes++ ) {
if ( *src_bytes == character )
return ( ( void * ) src_bytes );
}
return __res;
return NULL;
}
#endif
#ifndef __HAVE_ARCH_STRCASECMP
int strcasecmp(const char *a, const char *b)
{
while (*a && *b && (*a & ~0x20) == (*b & ~0x20)) {a++; b++; }
return((*a & ~0x20) - (*b & ~0x20));
}
#endif
#ifndef __HAVE_ARCH_STRCHR
/**
* strchr - Find the first occurrence of a character in a string
* @s: The string to be searched
* @c: The character to search for
* Swap memory regions
*
* @v first First region
* @v second Second region
* @v len Length
* @ret first First region
*/
char * strchr(const char * s, int c)
{
for(; *s != (char) c; ++s)
if (*s == '\0')
void * memswap ( void *first, void *second, size_t len ) {
uint8_t *first_bytes = first;
uint8_t *second_bytes = second;
uint8_t temp;
for ( ; len-- ; first_bytes++, second_bytes++ ) {
temp = *first_bytes;
*first_bytes = *second_bytes;
*second_bytes = temp;
}
return first;
}
/**
* Compare strings
*
* @v first First string
* @v second Second string
* @ret diff Difference
*/
int strcmp ( const char *first, const char *second ) {
return strncmp ( first, second, ~( ( size_t ) 0 ) );
}
/**
* Compare strings
*
* @v first First string
* @v second Second string
* @v max Maximum length to compare
* @ret diff Difference
*/
int strncmp ( const char *first, const char *second, size_t max ) {
const uint8_t *first_bytes = ( ( const uint8_t * ) first );
const uint8_t *second_bytes = ( ( const uint8_t * ) second );
int diff;
for ( ; max-- ; first_bytes++, second_bytes++ ) {
diff = ( *second_bytes - *first_bytes );
if ( diff )
return diff;
if ( ! *first_bytes )
return 0;
}
return 0;
}
/**
* Compare case-insensitive strings
*
* @v first First string
* @v second Second string
* @ret diff Difference
*/
int strcasecmp ( const char *first, const char *second ) {
const uint8_t *first_bytes = ( ( const uint8_t * ) first );
const uint8_t *second_bytes = ( ( const uint8_t * ) second );
int diff;
for ( ; ; first_bytes++, second_bytes++ ) {
diff = ( toupper ( *second_bytes ) -
toupper ( *first_bytes ) );
if ( diff )
return diff;
if ( ! *first_bytes )
return 0;
}
}
/**
* Get length of string
*
* @v src String
* @ret len Length
*/
size_t strlen ( const char *src ) {
return strnlen ( src, ~( ( size_t ) 0 ) );
}
/**
* Get length of string
*
* @v src String
* @v max Maximum length
* @ret len Length
*/
size_t strnlen ( const char *src, size_t max ) {
const uint8_t *src_bytes = ( ( const uint8_t * ) src );
size_t len = 0;
while ( max-- && *(src_bytes++) )
len++;
return len;
}
/**
* Find character within a string
*
* @v src String
* @v character Character to find
* @ret found Found character, or NULL if not found
*/
char * strchr ( const char *src, int character ) {
const uint8_t *src_bytes = ( ( const uint8_t * ) src );
for ( ; ; src_bytes++ ) {
if ( *src_bytes == character )
return ( ( char * ) src_bytes );
if ( ! *src_bytes )
return NULL;
return (char *) s;
}
}
#endif
#ifndef __HAVE_ARCH_STRRCHR
/**
* strrchr - Find the last occurrence of a character in a string
* @s: The string to be searched
* @c: The character to search for
*/
char * strrchr(const char * s, int c)
{
const char *p = s + strlen(s);
do {
if (*p == (char)c)
return (char *)p;
} while (--p >= s);
return NULL;
}
#endif
#ifndef __HAVE_ARCH_STRLEN
/**
* strlen - Find the length of a string
* @s: The string to be sized
*/
size_t strlen(const char * s)
{
const char *sc;
for (sc = s; *sc != '\0'; ++sc)
/* nothing */;
return sc - s;
}
#endif
#ifndef __HAVE_ARCH_STRNLEN
/**
* strnlen - Find the length of a length-limited string
* @s: The string to be sized
* @count: The maximum number of bytes to search
*/
size_t strnlen(const char * s, size_t count)
{
const char *sc;
for (sc = s; count-- && *sc != '\0'; ++sc)
/* nothing */;
return sc - s;
}
#endif
#ifndef __HAVE_ARCH_MEMSET
/**
* memset - Fill a region of memory with the given value
* @s: Pointer to the start of the area.
* @c: The byte to fill the area with
* @count: The size of the area.
* Find rightmost character within a string
*
* Do not use memset() to access IO space, use memset_io() instead.
* @v src String
* @v character Character to find
* @ret found Found character, or NULL if not found
*/
void * memset(void * s,int c,size_t count)
{
char *xs = (char *) s;
char * strrchr ( const char *src, int character ) {
const uint8_t *src_bytes = ( ( const uint8_t * ) src );
const uint8_t *start = src_bytes;
while (count--)
*xs++ = c;
return s;
while ( *src_bytes )
src_bytes++;
for ( src_bytes-- ; src_bytes >= start ; src_bytes-- ) {
if ( *src_bytes == character )
return ( ( char * ) src_bytes );
}
return NULL;
}
#endif
#ifndef __HAVE_ARCH_MEMCPY
/**
* memcpy - Copy one area of memory to another
* @dest: Where to copy to
* @src: Where to copy from
* @count: The size of the area.
* Find substring
*
* You should not use this function to access IO space, use memcpy_toio()
* or memcpy_fromio() instead.
* @v haystack String
* @v needle Substring
* @ret found Found substring, or NULL if not found
*/
void * memcpy(void * dest,const void *src,size_t count)
{
char *tmp = (char *) dest, *s = (char *) src;
char * strstr ( const char *haystack, const char *needle ) {
size_t len = strlen ( needle );
while (count--)
*tmp++ = *s++;
return dest;
for ( ; *haystack ; haystack++ ) {
if ( memcmp ( haystack, needle, len ) == 0 )
return ( ( char * ) haystack );
}
return NULL;
}
#endif
#ifndef __HAVE_ARCH_MEMMOVE
/**
* memmove - Copy one area of memory to another
* @dest: Where to copy to
* @src: Where to copy from
* @count: The size of the area.
* Copy string
*
* Unlike memcpy(), memmove() copes with overlapping areas.
* @v dest Destination string
* @v src Source string
* @ret dest Destination string
*/
void * memmove(void * dest,const void *src,size_t count)
{
char *tmp, *s;
char * strcpy ( char *dest, const char *src ) {
const uint8_t *src_bytes = ( ( const uint8_t * ) src );
uint8_t *dest_bytes = ( ( uint8_t * ) dest );
if (dest <= src) {
tmp = (char *) dest;
s = (char *) src;
while (count--)
*tmp++ = *s++;
}
else {
tmp = (char *) dest + count;
s = (char *) src + count;
while (count--)
*--tmp = *--s;
}
return dest;
}
#endif
#ifndef __HAVE_ARCH_MEMCMP
/**
* memcmp - Compare two areas of memory
* @cs: One area of memory
* @ct: Another area of memory
* @count: The size of the area.
*/
int memcmp(const void * cs,const void * ct,size_t count)
{
const unsigned char *su1, *su2;
int res = 0;
for( su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
if ((res = *su1 - *su2) != 0)
/* We cannot use strncpy(), since that would pad the destination */
for ( ; ; src_bytes++, dest_bytes++ ) {
*dest_bytes = *src_bytes;
if ( ! *dest_bytes )
break;
return res;
}
#endif
#ifndef __HAVE_ARCH_STRSTR
/**
* strstr - Find the first substring in a %NUL terminated string
* @s1: The string to be searched
* @s2: The string to search for
*/
char * strstr(const char * s1,const char * s2)
{
int l1, l2;
l2 = strlen(s2);
if (!l2)
return (char *) s1;
l1 = strlen(s1);
while (l1 >= l2) {
l1--;
if (!memcmp(s1,s2,l2))
return (char *) s1;
s1++;
}
return NULL;
return dest;
}
#endif
#ifndef __HAVE_ARCH_MEMCHR
/**
* memchr - Find a character in an area of memory.
* @s: The memory area
* @c: The byte to search for
* @n: The size of the area.
* Copy string
*
* returns the address of the first occurrence of @c, or %NULL
* if @c is not found
* @v dest Destination string
* @v src Source string
* @v max Maximum length
* @ret dest Destination string
*/
void * memchr(const void *s, int c, size_t n)
{
const unsigned char *p = s;
while (n-- != 0) {
if ((unsigned char)c == *p++) {
return (void *)(p-1);
}
char * strncpy ( char *dest, const char *src, size_t max ) {
const uint8_t *src_bytes = ( ( const uint8_t * ) src );
uint8_t *dest_bytes = ( ( uint8_t * ) dest );
for ( ; max ; max--, src_bytes++, dest_bytes++ ) {
*dest_bytes = *src_bytes;
if ( ! *dest_bytes )
break;
}
return NULL;
while ( max-- )
*(dest_bytes++) = '\0';
return dest;
}
#endif
/**
* Concatenate string
*
* @v dest Destination string
* @v src Source string
* @ret dest Destination string
*/
char * strcat ( char *dest, const char *src ) {
char * strndup(const char *s, size_t n)
{
size_t len = strnlen(s,n);
char *new;
strcpy ( ( dest + strlen ( dest ) ), src );
return dest;
}
new = malloc(len+1);
if (new) {
new[len] = '\0';
memcpy(new,s,len);
/**
* Duplicate string
*
* @v src Source string
* @ret dup Duplicated string, or NULL if allocation failed
*/
char * strdup ( const char *src ) {
return strndup ( src, ~( ( size_t ) 0 ) );
}
/**
* Duplicate string
*
* @v src Source string
* @v max Maximum length
* @ret dup Duplicated string, or NULL if allocation failed
*/
char * strndup ( const char *src, size_t max ) {
size_t len = strnlen ( src, max );
char *dup;
dup = malloc ( len + 1 /* NUL */ );
if ( dup ) {
memcpy ( dup, src, len );
dup[len] = '\0';
}
return new;
}
char * strdup(const char *s) {
return strndup(s, ~((size_t)0));
return dup;
}

View File

@ -75,7 +75,7 @@ static struct errortab * find_closest_error ( int errno ) {
* call to strerror().
*
*/
const char * strerror ( int errno ) {
char * strerror ( int errno ) {
static char errbuf[64];
struct errortab *errortab;

View File

@ -1,46 +1,53 @@
/*
* Copyright (C) 1991, 1992 Linus Torvalds
* Copyright (C) 2004 Tobias Lorenz
#ifndef _STRING_H
#define _STRING_H
/** @file
*
* string handling functions
* based on linux/include/linux/ctype.h
* and linux/include/linux/string.h
* String functions
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
FILE_LICENCE ( GPL2_ONLY );
#ifndef ETHERBOOT_STRING_H
#define ETHERBOOT_STRING_H
FILE_LICENCE ( GPL2_OR_LATER );
#include <stddef.h>
#include <bits/string.h>
char * strcpy(char * dest,const char *src) __nonnull;
char * strncpy(char * dest,const char *src,size_t count) __nonnull;
char * strcat(char * dest, const char * src) __nonnull;
int __pure strcmp(const char * cs,const char * ct) __nonnull;
int __pure strncmp(const char * cs,const char * ct,
size_t count) __nonnull;
char * __pure strchr(const char * s, int c) __nonnull;
char * __pure strrchr(const char * s, int c) __nonnull;
size_t __pure strlen(const char * s) __nonnull;
size_t __pure strnlen(const char * s, size_t count) __nonnull;
char * __pure strpbrk(const char * cs,const char * ct) __nonnull;
char * strsep(char **s, const char *ct) __nonnull;
void * memset(void * s,int c,size_t count) __nonnull;
/* Architecture-specific code is expected to provide these functions,
* but may instead explicitly choose to use the generic versions.
*/
void * memset ( void *dest, int character, size_t len ) __nonnull;
void * memcpy ( void *dest, const void *src, size_t len ) __nonnull;
void * memmove(void * dest,const void *src,size_t count) __nonnull;
int __pure memcmp(const void * cs,const void * ct,
size_t count) __nonnull;
char * __pure strstr(const char * s1,const char * s2) __nonnull;
void * __pure memchr(const void *s, int c, size_t n) __nonnull;
char * __malloc strdup(const char *s) __nonnull;
char * __malloc strndup(const char *s, size_t n) __nonnull;
void * memmove ( void *dest, const void *src, size_t len ) __nonnull;
extern void * generic_memset ( void *dest, int character,
size_t len ) __nonnull;
extern void * generic_memcpy ( void *dest, const void *src,
size_t len ) __nonnull;
extern void * generic_memmove ( void *dest, const void *src,
size_t len ) __nonnull;
extern const char * __pure strerror ( int errno );
extern int __pure memcmp ( const void *first, const void *second,
size_t len ) __nonnull;
extern void * __pure memchr ( const void *src, int character,
size_t len ) __nonnull;
extern void * memswap ( void *dest, void *src, size_t len ) __nonnull;
extern int __pure strcmp ( const char *first, const char *second ) __nonnull;
extern int __pure strncmp ( const char *first, const char *second,
size_t max ) __nonnull;
extern size_t __pure strlen ( const char *src ) __nonnull;
extern size_t __pure strnlen ( const char *src, size_t max ) __nonnull;
extern char * __pure strchr ( const char *src, int character ) __nonnull;
extern char * __pure strrchr ( const char *src, int character ) __nonnull;
extern char * __pure strstr ( const char *haystack,
const char *needle ) __nonnull;
extern char * strcpy ( char *dest, const char *src ) __nonnull;
extern char * strncpy ( char *dest, const char *src, size_t max ) __nonnull;
extern char * strcat ( char *dest, const char *src ) __nonnull;
extern char * __malloc strdup ( const char *src ) __nonnull;
extern char * __malloc strndup ( const char *src, size_t max ) __nonnull;
extern char * __pure strpbrk ( const char *string,
const char *delim ) __nonnull;
extern char * strsep ( char **string, const char *delim ) __nonnull;
#endif /* ETHERBOOT_STRING */
extern char * __pure strerror ( int errno );
#endif /* _STRING_H */

View File

@ -1,12 +1,23 @@
#ifndef _STRINGS_H
#define _STRINGS_H
/** @file
*
* String functions
*
*/
FILE_LICENCE ( GPL2_OR_LATER );
#include <limits.h>
#include <string.h>
#include <bits/strings.h>
/**
* 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;
@ -41,6 +52,12 @@ __constant_flsll ( unsigned long long x ) {
return r;
}
/**
* 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 );
@ -49,24 +66,55 @@ __constant_flsl ( unsigned long x ) {
int __flsll ( long long x );
int __flsl ( long 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 )
extern int strcasecmp ( const char *s1, const char *s2 );
/**
* 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 n ) {
memmove ( dest, src, n );
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 *s, size_t n ) {
memset ( s, 0, n );
bzero ( void *dest, size_t len ) {
memset ( dest, 0, len );
}
int __pure strcasecmp ( const char *first, const char *second ) __nonnull;
#endif /* _STRINGS_H */