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authorUlrich Drepper <drepper@redhat.com>1999-04-28 23:13:52 +0000
committerUlrich Drepper <drepper@redhat.com>1999-04-28 23:13:52 +0000
commitc4563d2d668675c2d5083f6ad01c801d6ccbe013 (patch)
tree1e6af86f8c33743c81080dffb17a8e8209825c06 /sysdeps/generic/strchrnul.c
parent89afc233db58d3de7669332d141113ec2ca4991d (diff)
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Update.
1999-04-28  Ulrich Drepper  <drepper@cygnus.com>

	* argp/argp-ba.c (argp_program_bug_address): Don't initialize with 0.
	* argp/argp-parse.c (_argp_hang): Likewise.
	* argp/argp-pv.c (argp_program_version): Likewise.
	* argp/argp-pvh.c (argp_program_version_hook): Likewise.
	* inet/ether_hton.c (ether_hton, startp): Likewise.
	* inet/ether_ntoh.c (ether_ntoh, startp): Likewise.
	* inet/getnetgrent_r.c (setup, startp): Likewise.
	* intl/loadmsgcat.c (_nl_msg_cat_cntr): Likewise.
	* intl/localealias.c (string_space, string_space_act, string_space_max,
	nmap, maxmap): Likewise.
	* libio/iopopen.c (proc_file_chain): Likewise.
	* libio/oldiopopen.c (old_proc_file_chain): Likewise.
	* locale/lc-collate.c (__collate_table, __collate_extra,
	__collate_element_hash, __collate_element_strings,
	__collate_element_values): Likewise.
	* malloc/mcheck.c (mcheck_used): Likewise.
	* malloc/mtrace.c (added_atexit_handler): Likewise.
	* malloc/set-freeres.c (already_called): Likewise.
	* misc/getpass.c (getpass) [buf, bufsize]: Likewise.
	* misc/syslog.c (LogStat, LogTag): Likewise.
	* nss/XXX-lookup.c (DATABASE_NAME_SYMBOL): Likewise.
	* nss/getXXbyYY_r.c (startp): Likewise.
	* posix/getopt.c (optarg, __getopt_initialized): Likewise.
	* posix/regex.c (init_syntax_once) [done]: Likewise.
	(debug): Likewise.
	* string/strfry.c (init): Likewise.
	* sunrpc/svc_run.c (svc_top): Likewise.
	* posix/euidaccess.c (have_ids): Likewise.
	* sysdeps/unix/sysv/linux/poll.c (must_emulate): Likewise.
	* sysdeps/unix/sysv/linux/ttyname.c (__ttyname, namelen): Likewise.
	* time/getdate.c (getdate_err): Likewise.
	* time/tzfile.c (transitions, type_idxs, types, zone_names, leaps):
	Likewise.
	* time/tzset.c (old_tz, is_initialized): Likewise.

	* inet/getnameinfo.c (nrl_domainname): Rewrite to allow initialization
	of static data with zero.
	* signal/allocrtsig.c (init): Likewise.

	* string/Makefile (routines): Add strchrnul.
	* string/Versions [GLIBC_2.1.1]: Add strchrnul.
	* string/string.c: Add strchrnul prototype.
	* include/string.h: Add __strchrnul prototype.
	* sysdeps/generic/strchrnul.c: New file.
	* sysdeps/i386/strchrnul.S: New file.
	* sysdeps/i386/bits/string.c: Add strchrnul optimization.
	* sysdeps/i386/i486/bits/string.c: Likewise.
	* argp/argp-help.c (argp_args_usage): Use __strchrnul.
	* inet/ether_line.c (ether_line): Likewise.
	* nscd/nscd_conf.c (nscd_parse_file): Likewise.
	* nss/nsswitch.c (nss_parse_file): Likewise.
	* posix/execvp.c (execvp): Likewise.
	* posix/fnmatch.c (internal_fnmatch): Likewise.
	* resolv/res_hconf.c (_res_hconv_init): Likewise.
	* resolv/res_init.c (res_init): Likewise.
	* stdlib/fmtmsg.c (init): Likewise.
	* stdlib/getsubopt.c (getsubopt): Likewise.

	* catgets/catgets.c (catopen): Only allocate one memory block.
	(catclose): Only one free call necessary.

	* catgets/open_catalog.c (__open_catalog): Simplify handling of
	file descriptor.

	* ctype/ctype-extn.c: Make __toascii_l and __isascii_l alias instead
	of real functions.  Simplify _tolower and _toupper.

	* grp/initgroups.c (compat_call): Remove unnecessary use of pointer
	variable.

	* iconv/gconv.h (struct gconv_info): Change data element from pointer
	to array of size 0.
	* iconv/gconv_open.c (__gconv_open): Allocate structures accordingly.
	* iconv/gconv_close.c (__gconv_close): Don't free data.

	* iconv/gconv_conf.c (add_alias): Avoid searching in tree twice to
	insert new alias.

	* iconv/gconv_db.c (add_derivation): More efficient copying.  Check
	for error while inserting in tree.

	* include/time.h: Pretty print.

	* inet/ruserpass.c: Rewrite use of toktab to avoid string pointers
	in table and lots of relocations.
	* posix/regex.c (regerror): Rewrite use of re_error_msgid to avoid
	string pointers in table and lots of relocations.

	* intl/finddomain.c: Remove definition of strchr macro.

	* io/ftw.c (nftw_arr, ftw_arr): Make const.

	* locale/loadlocale.c (_nl_load_locale): Optimize string copying.

	* locale/localeinfo.h (_nl_category_names): Change into an array with
	fixed width char string elements.
	* locale/setlocale.c (_nl_category_names): Likewise.
	(_nl_current): Make global.
	* locale/nl_langinfo.c (nldata): Removed.  Use _nl_current now.

	* malloc/Makefile (distribute): Add stackinfo.h.
	* sysdeps/generic/stackinfo.h: New file.
	* sysdeps/i386/stackinfo.h: New file.
	* posix/execl.c: Use stackinfo.h in optimizing alloca use.
	* posix/execle.c: Likewise.
	* posix/execlp.c: Likewise.

	* nis/nis_table.c (__create_ib_request): Always use realloc.

	* posix/execvp.c (execute): Rename to script_execute and keep only
	code to execute using shell.
	(execvp): Call execv directly and only fall back on script_execute.

	* resolv/inet_net_pton.c (inet_net_pton_ipv4): Remove digits define
	and always use xdigits instead.

	* resolv/res_init.c (res_init): Use rawmemchr instead of strchr
	where appropriate.

	* stdlib/fpioconst.h (__tens): New declaration.
	(struct mp_power): Remove array, add arrayoff element.
	* stdlib/fpioconst.c: Replace definitions of _ten_p* arrays by one
	__tens array and add in _fpioconst_pow10 offsets into __tens.
	* stdio-common/printf_fp.c: Rewrite to use new __tens array.
	* stdlib/strtod.c: Likewise.

	* stdlib/a64l.c (a64l_table): Avoid unnecessary elements.

	* stdlib/exit.c: Rewrite to use __exit_funcs being as sign for end
	of the list.
	* stdlib/atexit.c (__exit_funcs): Don't initialize.

	* stdlib/fmtmsg.c (keywords): Make name element fixed width array.

	* sunrpc/clnt_perr.c: Rewrite clnt_sperrno and auth_errmsg to use
	a single and an array with offsets.

	* sunrpc/des_soft.c (partab): Make it const.

	* sunrpc/key_call.c (trytimeout, tottimeout): Make const.
	(__key_encryptsession_pk_LOCAL): Don't initialize with 0.
	(__key_decryptsession_pk_LOCAL): Likewise.
	(__key_gendes_LOCAL): Likewise.
	(MESSENGER): Mark const.
	(key_call_private_main): Don't initialize with 0.
	(use_keyenvoy): Don't initialize with 0.
	(key_call): Rewrite to reverse logic of use_doors variable.

	* sunrpc/netname.c (OPSYS): Define as array, not pointer.
	(startp): Don't initialize with zero.

	* sunrpc/openchild.c (_openchild): Make first argument const.

	* sunrpc/pmap_rmt.c (timeout): Mark const.
	* sunrpc/xcrypt.c (hex): Likewise.

	* sysdeps/unix/sysv/linux/getcwd.c: Rewrite to allow omitting
	initialization of global variables.
	* sysdeps/unix/sysv/linux/getpt.c: Likewise.
	* sysdeps/unix/sysv/linux/if_index.c: Likewise.
	* termios/tcgetsid.c: Likewise.

	* sysdeps/unix/sysv/linux/i386/dl-procinfo.h (x86_cap_flags): Change
	fxsr to osfxsr.

	* time/tzfile.c (__tzfile_read): Rewrite to allocate only one memory
	block.  Add function to free memory if wanted.
	* time/tzset.c (tzset_internal): Pass extra argument to __tzfile_read.

	* wcsmbs/wcsmbsload.c (to_wc, to_mb): Correct initializers.

	* wcsmbs/wmemset.c: Little code optimization.
Diffstat (limited to 'sysdeps/generic/strchrnul.c')
-rw-r--r--sysdeps/generic/strchrnul.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/sysdeps/generic/strchrnul.c b/sysdeps/generic/strchrnul.c
new file mode 100644
index 0000000000..1d6ece5332
--- /dev/null
+++ b/sysdeps/generic/strchrnul.c
@@ -0,0 +1,166 @@
+/* Copyright (C) 1991, 93, 94, 95, 96, 97, 99 Free Software Foundation, Inc.
+   Based on strlen implementation by Torbjorn Granlund (tege@sics.se),
+   with help from Dan Sahlin (dan@sics.se) and
+   bug fix and commentary by Jim Blandy (jimb@ai.mit.edu);
+   adaptation to strchr 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 Library General Public License as
+   published by the Free Software Foundation; either version 2 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <string.h>
+
+#undef __strchrnul
+#undef strchrnul
+
+/* Find the first occurrence of C in S or the final NUL byte.  */
+char *
+__strchrnul (s, c)
+     const char *s;
+     int c;
+{
+  const unsigned char *char_ptr;
+  const unsigned long int *longword_ptr;
+  unsigned long int longword, magic_bits, charmask;
+
+  c = (unsigned char) c;
+
+  /* Handle the first few characters by reading one character at a time.
+     Do this until CHAR_PTR is aligned on a longword boundary.  */
+  for (char_ptr = s; ((unsigned long int) char_ptr
+		      & (sizeof (longword) - 1)) != 0;
+       ++char_ptr)
+    if (*char_ptr == c || *char_ptr == '\0')
+      return (void *) char_ptr;
+
+  /* All these elucidatory comments refer to 4-byte longwords,
+     but the theory applies equally well to 8-byte longwords.  */
+
+  longword_ptr = (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.  */
+  switch (sizeof (longword))
+    {
+    case 4: magic_bits = 0x7efefeffL; break;
+    case 8: magic_bits = ((0x7efefefeL << 16) << 16) | 0xfefefeffL; break;
+    default:
+      abort ();
+    }
+
+  /* Set up a longword, each of whose bytes is C.  */
+  charmask = c | (c << 8);
+  charmask |= charmask << 16;
+  if (sizeof (longword) > 4)
+    /* Do the shift in two steps to avoid a warning if long has 32 bits.  */
+    charmask |= (charmask << 16) << 16;
+  if (sizeof (longword) > 8)
+    abort ();
+
+  /* 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.  */
+  for (;;)
+    {
+      /* 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 as well as 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++;
+
+      /* 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 ||
+
+	  /* That caught zeroes.  Now test for C.  */
+	  ((((longword ^ charmask) + magic_bits) ^ ~(longword ^ charmask))
+	   & ~magic_bits) != 0)
+	{
+	  /* Which of the bytes was C or zero?
+	     If none of them were, it was a misfire; continue the search.  */
+
+	  const unsigned char *cp = (const unsigned char *) (longword_ptr - 1);
+
+	  if (*cp == c || *cp == '\0')
+	    return (char *) cp;
+	  if (*++cp == c || *cp == '\0')
+	    return (char *) cp;
+	  if (*++cp == c || *cp == '\0')
+	    return (char *) cp;
+	  if (*++cp == c || *cp == '\0')
+	    return (char *) cp;
+	  if (sizeof (longword) > 4)
+	    {
+	      if (*++cp == c || *cp == '\0')
+		return (char *) cp;
+	      if (*++cp == c || *cp == '\0')
+		return (char *) cp;
+	      if (*++cp == c || *cp == '\0')
+		return (char *) cp;
+	      if (*++cp == c || *cp == '\0')
+		return (char *) cp;
+	    }
+	}
+    }
+
+  /* This should never happen.  */
+  return NULL;
+}
+
+weak_alias (__strchrnul, strchrnul)