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added memrchr and dirname

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git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@24985 a95241bf-73f2-0310-859d-f6bbb57e9c96
This commit is contained in:
Jérôme Duval 2008-04-16 18:49:23 +00:00
parent b9f23a3497
commit 6112fe9a8d
6 changed files with 483 additions and 0 deletions
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210
src/system/libroot/posix/glibc/arch/generic/memrchr.c Normal file
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/* memrchr -- find the last occurrence of a byte in a memory block
Copyright (C) 1991, 93, 96, 97, 99, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Based on strlen implementation by Torbjorn Granlund (tege@sics.se),
with help from Dan Sahlin (dan@sics.se) and
commentary by Jim Blandy (jimb@ai.mit.edu);
adaptation to memchr suggested by Dick Karpinski (dick@cca.ucsf.edu),
and implemented by Roland McGrath (roland@ai.mit.edu).
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <stdlib.h>
#ifdef HAVE_CONFIG_H
# include <config.h>
#endif
#undef __ptr_t
#if defined __cplusplus || (defined __STDC__ && __STDC__)
# define __ptr_t void *
#else /* Not C++ or ANSI C. */
# define __ptr_t char *
#endif /* C++ or ANSI C. */
#if defined _LIBC
# include <string.h>
# include <memcopy.h>
#else
# define reg_char char
#endif
#if defined HAVE_LIMITS_H || defined _LIBC
# include <limits.h>
#endif
#define LONG_MAX_32_BITS 2147483647
#ifndef LONG_MAX
# define LONG_MAX LONG_MAX_32_BITS
#endif
#include <sys/types.h>
#undef __memrchr
#undef memrchr
#ifndef weak_alias
# define __memrchr memrchr
#endif
/* Search no more than N bytes of S for C. */
__ptr_t
__memrchr (s, c_in, n)
const __ptr_t s;
int c_in;
size_t n;
{
const unsigned char *char_ptr;
const unsigned long int *longword_ptr;
unsigned long int longword, magic_bits, charmask;
unsigned reg_char c;
c = (unsigned char) c_in;
/* Handle the last few characters by reading one character at a time.
Do this until CHAR_PTR is aligned on a longword boundary. */
for (char_ptr = (const unsigned char *) s + n;
n > 0 && ((unsigned long int) char_ptr
& (sizeof (longword) - 1)) != 0;
--n)
if (*--char_ptr == c)
return (__ptr_t) char_ptr;
/* All these elucidatory comments refer to 4-byte longwords,
but the theory applies equally well to 8-byte longwords. */
longword_ptr = (const unsigned long int *) char_ptr;
/* Bits 31, 24, 16, and 8 of this number are zero. Call these bits
the "holes." Note that there is a hole just to the left of
each byte, with an extra at the end:
bits: 01111110 11111110 11111110 11111111
bytes: AAAAAAAA BBBBBBBB CCCCCCCC DDDDDDDD
The 1-bits make sure that carries propagate to the next 0-bit.
The 0-bits provide holes for carries to fall into. */
if (sizeof (longword) != 4 && sizeof (longword) != 8)
abort ();
#if LONG_MAX <= LONG_MAX_32_BITS
magic_bits = 0x7efefeff;
#else
magic_bits = ((unsigned long int) 0x7efefefe << 32) | 0xfefefeff;
#endif
/* Set up a longword, each of whose bytes is C. */
charmask = c | (c << 8);
charmask |= charmask << 16;
#if LONG_MAX > LONG_MAX_32_BITS
charmask |= charmask << 32;
#endif
/* Instead of the traditional loop which tests each character,
we will test a longword at a time. The tricky part is testing
if *any of the four* bytes in the longword in question are zero. */
while (n >= sizeof (longword))
{
/* We tentatively exit the loop if adding MAGIC_BITS to
LONGWORD fails to change any of the hole bits of LONGWORD.
1) Is this safe? Will it catch all the zero bytes?
Suppose there is a byte with all zeros. Any carry bits
propagating from its left will fall into the hole at its
least significant bit and stop. Since there will be no
carry from its most significant bit, the LSB of the
byte to the left will be unchanged, and the zero will be
detected.
2) Is this worthwhile? Will it ignore everything except
zero bytes? Suppose every byte of LONGWORD has a bit set
somewhere. There will be a carry into bit 8. If bit 8
is set, this will carry into bit 16. If bit 8 is clear,
one of bits 9-15 must be set, so there will be a carry
into bit 16. Similarly, there will be a carry into bit
24. If one of bits 24-30 is set, there will be a carry
into bit 31, so all of the hole bits will be changed.
The one misfire occurs when bits 24-30 are clear and bit
31 is set; in this case, the hole at bit 31 is not
changed. If we had access to the processor carry flag,
we could close this loophole by putting the fourth hole
at bit 32!
So it ignores everything except 128's, when they're aligned
properly.
3) But wait! Aren't we looking for C, not zero?
Good point. So what we do is XOR LONGWORD with a longword,
each of whose bytes is C. This turns each byte that is C
into a zero. */
longword = *--longword_ptr ^ charmask;
/* Add MAGIC_BITS to LONGWORD. */
if ((((longword + magic_bits)
/* Set those bits that were unchanged by the addition. */
^ ~longword)
/* Look at only the hole bits. If any of the hole bits
are unchanged, most likely one of the bytes was a
zero. */
& ~magic_bits) != 0)
{
/* Which of the bytes was C? If none of them were, it was
a misfire; continue the search. */
const unsigned char *cp = (const unsigned char *) longword_ptr;
#if LONG_MAX > 2147483647
if (cp[7] == c)
return (__ptr_t) &cp[7];
if (cp[6] == c)
return (__ptr_t) &cp[6];
if (cp[5] == c)
return (__ptr_t) &cp[5];
if (cp[4] == c)
return (__ptr_t) &cp[4];
#endif
if (cp[3] == c)
return (__ptr_t) &cp[3];
if (cp[2] == c)
return (__ptr_t) &cp[2];
if (cp[1] == c)
return (__ptr_t) &cp[1];
if (cp[0] == c)
return (__ptr_t) cp;
}
n -= sizeof (longword);
}
char_ptr = (const unsigned char *) longword_ptr;
while (n-- > 0)
{
if (*--char_ptr == c)
return (__ptr_t) char_ptr;
}
return 0;
}
#ifdef weak_alias
weak_alias (__memrchr, memrchr)
#endif

1
src/system/libroot/posix/glibc/arch/x86/Jamfile
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@ -21,6 +21,7 @@ SubDirCcFlags -D_GNU_SOURCE -D_IEEE_LIBM ;
local genericSources =
cmp.c dbl2mpn.c divrem.c
memrchr.c
mpn2dbl.c mpn2flt.c mpn2ldbl.c
mul.c mul_n.c
e_cosh.c e_coshf.c # e_coshl.c

150
src/system/libroot/posix/glibc/include/arch/generic/memcopy.h Normal file
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/* memcopy.h -- definitions for memory copy functions. Generic C version.
Copyright (C) 1991, 1992, 1993, 1997, 2004 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Torbjorn Granlund (tege@sics.se).
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
/* The strategy of the memory functions is:
1. Copy bytes until the destination pointer is aligned.
2. Copy words in unrolled loops. If the source and destination
are not aligned in the same way, use word memory operations,
but shift and merge two read words before writing.
3. Copy the few remaining bytes.
This is fast on processors that have at least 10 registers for
allocation by GCC, and that can access memory at reg+const in one
instruction.
I made an "exhaustive" test of this memmove when I wrote it,
exhaustive in the sense that I tried all alignment and length
combinations, with and without overlap. */
#include <sys/cdefs.h>
#include <endian.h>
/* The macros defined in this file are:
BYTE_COPY_FWD(dst_beg_ptr, src_beg_ptr, nbytes_to_copy)
BYTE_COPY_BWD(dst_end_ptr, src_end_ptr, nbytes_to_copy)
WORD_COPY_FWD(dst_beg_ptr, src_beg_ptr, nbytes_remaining, nbytes_to_copy)
WORD_COPY_BWD(dst_end_ptr, src_end_ptr, nbytes_remaining, nbytes_to_copy)
MERGE(old_word, sh_1, new_word, sh_2)
[I fail to understand. I feel stupid. --roland]
*/
/* Type to use for aligned memory operations.
This should normally be the biggest type supported by a single load
and store. */
#define op_t unsigned long int
#define OPSIZ (sizeof(op_t))
/* Type to use for unaligned operations. */
typedef unsigned char byte;
/* Optimal type for storing bytes in registers. */
#define reg_char char
#if __BYTE_ORDER == __LITTLE_ENDIAN
#define MERGE(w0, sh_1, w1, sh_2) (((w0) >> (sh_1)) | ((w1) << (sh_2)))
#endif
#if __BYTE_ORDER == __BIG_ENDIAN
#define MERGE(w0, sh_1, w1, sh_2) (((w0) << (sh_1)) | ((w1) >> (sh_2)))
#endif
/* Copy exactly NBYTES bytes from SRC_BP to DST_BP,
without any assumptions about alignment of the pointers. */
#define BYTE_COPY_FWD(dst_bp, src_bp, nbytes) \
do \
{ \
size_t __nbytes = (nbytes); \
while (__nbytes > 0) \
{ \
byte __x = ((byte *) src_bp)[0]; \
src_bp += 1; \
__nbytes -= 1; \
((byte *) dst_bp)[0] = __x; \
dst_bp += 1; \
} \
} while (0)
/* Copy exactly NBYTES_TO_COPY bytes from SRC_END_PTR to DST_END_PTR,
beginning at the bytes right before the pointers and continuing towards
smaller addresses. Don't assume anything about alignment of the
pointers. */
#define BYTE_COPY_BWD(dst_ep, src_ep, nbytes) \
do \
{ \
size_t __nbytes = (nbytes); \
while (__nbytes > 0) \
{ \
byte __x; \
src_ep -= 1; \
__x = ((byte *) src_ep)[0]; \
dst_ep -= 1; \
__nbytes -= 1; \
((byte *) dst_ep)[0] = __x; \
} \
} while (0)
/* Copy *up to* NBYTES bytes from SRC_BP to DST_BP, with
the assumption that DST_BP is aligned on an OPSIZ multiple. If
not all bytes could be easily copied, store remaining number of bytes
in NBYTES_LEFT, otherwise store 0. */
extern void _wordcopy_fwd_aligned (long int, long int, size_t) __THROW;
extern void _wordcopy_fwd_dest_aligned (long int, long int, size_t) __THROW;
#define WORD_COPY_FWD(dst_bp, src_bp, nbytes_left, nbytes) \
do \
{ \
if (src_bp % OPSIZ == 0) \
_wordcopy_fwd_aligned (dst_bp, src_bp, (nbytes) / OPSIZ); \
else \
_wordcopy_fwd_dest_aligned (dst_bp, src_bp, (nbytes) / OPSIZ); \
src_bp += (nbytes) & -OPSIZ; \
dst_bp += (nbytes) & -OPSIZ; \
(nbytes_left) = (nbytes) % OPSIZ; \
} while (0)
/* Copy *up to* NBYTES_TO_COPY bytes from SRC_END_PTR to DST_END_PTR,
beginning at the words (of type op_t) right before the pointers and
continuing towards smaller addresses. May take advantage of that
DST_END_PTR is aligned on an OPSIZ multiple. If not all bytes could be
easily copied, store remaining number of bytes in NBYTES_REMAINING,
otherwise store 0. */
extern void _wordcopy_bwd_aligned (long int, long int, size_t) __THROW;
extern void _wordcopy_bwd_dest_aligned (long int, long int, size_t) __THROW;
#define WORD_COPY_BWD(dst_ep, src_ep, nbytes_left, nbytes) \
do \
{ \
if (src_ep % OPSIZ == 0) \
_wordcopy_bwd_aligned (dst_ep, src_ep, (nbytes) / OPSIZ); \
else \
_wordcopy_bwd_dest_aligned (dst_ep, src_ep, (nbytes) / OPSIZ); \
src_ep -= (nbytes) & -OPSIZ; \
dst_ep -= (nbytes) & -OPSIZ; \
(nbytes_left) = (nbytes) % OPSIZ; \
} while (0)
/* Threshold value for when to enter the unrolled loops. */
#define OP_T_THRES 16

1
src/system/libroot/posix/glibc/misc/Jamfile
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@ -13,6 +13,7 @@ SubDirSysHdrs $(HAIKU_TOP) src system libroot posix glibc ;
SubDirCcFlags -D_GNU_SOURCE -DUSE_IN_LIBIO ;
MergeObject posix_gnu_misc.o :
dirname.c
tsearch.c
efgcvt.c
efgcvt_r.c

81
src/system/libroot/posix/glibc/misc/dirname.c Normal file
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/* dirname - return directory part of PATH.
Copyright (C) 1996, 2000, 2001, 2002 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <libgen.h>
#include <string.h>
char *
dirname (char *path)
{
static const char dot[] = ".";
char *last_slash;
/* Find last '/'. */
last_slash = path != NULL ? strrchr (path, '/') : NULL;
if (last_slash != NULL && last_slash != path && last_slash[1] == '\0')
{
/* Determine whether all remaining characters are slashes. */
char *runp;
for (runp = last_slash; runp != path; --runp)
if (runp[-1] != '/')
break;
/* The '/' is the last character, we have to look further. */
if (runp != path)
last_slash = __memrchr (path, '/', runp - path);
}
if (last_slash != NULL)
{
/* Determine whether all remaining characters are slashes. */
char *runp;
for (runp = last_slash; runp != path; --runp)
if (runp[-1] != '/')
break;
/* Terminate the path. */
if (runp == path)
{
/* The last slash is the first character in the string. We have to
return "/". As a special case we have to return "//" if there
are exactly two slashes at the beginning of the string. See
XBD 4.10 Path Name Resolution for more information. */
if (last_slash == path + 1)
++last_slash;
else
last_slash = path + 1;
}
else
last_slash = runp;
last_slash[0] = '\0';
}
else
/* This assignment is ill-designed but the XPG specs require to
return a string containing "." in any case no directory part is
found and so a static and constant string is required. */
path = (char *) dot;
return path;
}

40
src/system/libroot/posix/glibc/misc/libgen.h Normal file
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@ -0,0 +1,40 @@
/* Copyright (C) 1996, 1997, 1999, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#ifndef _LIBGEN_H
#define _LIBGEN_H 1
#include <features.h>
__BEGIN_DECLS
/* Return directory part of PATH or "." if none is available. */
extern char *dirname (char *__path) __THROW;
/* Return final component of PATH.
This is the weird XPG version of this function. It sometimes will
modify its argument. Therefore we normally use the GNU version (in
<string.h>) and only if this header is included make the XPG
version available under the real name. */
extern char *__xpg_basename (char *__path) __THROW;
#define basename __xpg_basename
__END_DECLS
#endif /* libgen.h */