lib/str-two-way.h


Log

Author Commit Date CI Message
Paul Eggert 341111f6 2012-02-09T21:39:05 maint: replace FSF snail-mail addresses with URLs * config/argz.mk, lib/accept4.c, lib/alignof.h, lib/alloca.in.h: * lib/alphasort.c, lib/arcfour.c, lib/arcfour.h, lib/arctwo.c: * lib/arctwo.h, lib/argz.c, lib/arpa_inet.in.h, lib/asnprintf.c: * lib/asprintf.c, lib/assert.in.h, lib/base32.c, lib/base32.h: * lib/base64.c, lib/base64.h, lib/c-ctype.c, lib/c-ctype.h: * lib/c-strcase.h, lib/c-strcasecmp.c, lib/c-strncasecmp.c: * lib/check-version.c, lib/check-version.h, lib/config.charset: * lib/ctype.in.h, lib/des.c, lib/des.h, lib/dup3.c, lib/errno.in.h: * lib/float+.h, lib/fnmatch.c, lib/fnmatch.in.h, lib/fnmatch_loop.c: * lib/fseeko.c, lib/gai_strerror.c, lib/gc-gnulib.c: * lib/gc-libgcrypt.c, lib/gc-pbkdf2-sha1.c, lib/gc.h: * lib/getaddrinfo.c, lib/getdelim.c, lib/getfilecon.c, lib/getline.c: * lib/getlogin_r.c, lib/getpass.c, lib/getpass.h, lib/gettext.h: * lib/gettimeofday.c, lib/glob.in.h, lib/glthread/cond.c: * lib/glthread/cond.h, lib/glthread/lock.c, lib/glthread/lock.h: * lib/glthread/thread.c, lib/glthread/thread.h: * lib/glthread/threadlib.c, lib/glthread/yield.h, lib/hmac-md5.c: * lib/hmac-sha1.c, lib/hmac.h, lib/iconv.c, lib/iconv.in.h: * lib/iconv_close.c, lib/iconv_open.c, lib/inet_ntop.c, lib/isfinite.c: * lib/isinf.c, lib/iswblank.c, lib/langinfo.in.h, lib/link.c: * lib/localcharset.c, lib/localcharset.h, lib/lseek.c, lib/malloc.c: * lib/malloca.c, lib/malloca.h, lib/md2.c, lib/md2.h, lib/md4.c: * lib/md4.h, lib/md5.c, lib/md5.h, lib/memmem.c, lib/mempcpy.c: * lib/memset.c, lib/memxor.c, lib/memxor.h, lib/minmax.h, lib/mktime.c: * lib/msvc-inval.c, lib/msvc-inval.h, lib/msvc-nothrow.c: * lib/msvc-nothrow.h, lib/netdb.in.h, lib/netinet_in.in.h, lib/nproc.c: * lib/nproc.h, lib/obstack_printf.c, lib/pathmax.h, lib/pipe.c: * lib/pipe2.c, lib/poll.c, lib/poll.in.h, lib/printf-args.c: * lib/printf-args.h, lib/printf-parse.c, lib/printf-parse.h: * lib/pselect.c, lib/pthread.in.h, lib/pty-private.h, lib/pty.in.h: * lib/read-file.c, lib/read-file.h, lib/ref-add.sin, lib/ref-del.sin: * lib/regcomp.c, lib/regex.c, lib/regex.h, lib/regex_internal.c: * lib/regex_internal.h, lib/regexec.c, lib/rijndael-alg-fst.c: * lib/rijndael-alg-fst.h, lib/rijndael-api-fst.c: * lib/rijndael-api-fst.h, lib/rint.c, lib/rintf.c, lib/rintl.c: * lib/round.c, lib/roundf.c, lib/roundl.c, lib/scandir.c, lib/select.c: * lib/sha1.c, lib/sha1.h, lib/size_max.h, lib/snprintf.c: * lib/stdalign.in.h, lib/stdarg.in.h, lib/stdbool.in.h: * lib/stddef.in.h, lib/stdint.in.h, lib/stdio.in.h, lib/str-kmp.h: * lib/str-two-way.h, lib/strcasecmp.c, lib/strcasestr.c, lib/strdup.c: * lib/striconv.c, lib/striconv.h, lib/string.in.h, lib/strings.in.h: * lib/strncasecmp.c, lib/strndup.c, lib/strnlen.c, lib/strpbrk.c: * lib/strptime.c, lib/strsep.c, lib/strstr.c, lib/strverscmp.c: * lib/sys_file.in.h, lib/sys_ioctl.in.h, lib/sys_select.in.h: * lib/sys_socket.in.h, lib/sys_stat.in.h, lib/sys_time.in.h: * lib/sys_times.in.h, lib/sys_types.in.h, lib/sys_uio.in.h: * lib/sys_utsname.in.h, lib/sys_wait.in.h, lib/tcgetsid.c: * lib/termios.in.h, lib/time.in.h, lib/time_r.c, lib/timegm.c: * lib/times.c, lib/unictype/3level.h, lib/unictype/3levelbit.h: * lib/unistd.in.h, lib/vasnprintf.c, lib/vasnprintf.h, lib/vasprintf.c: * lib/vsnprintf.c, lib/waitpid.c, lib/wchar.in.h, lib/wctype.in.h: * lib/xsize.h, tests/test-closein.c, tests/test-des.c: * tests/test-fclose.c, tests/test-fgetc.c, tests/test-filevercmp.c: * tests/test-fputc.c, tests/test-fread.c, tests/test-fwrite.c: * tests/test-gc-arcfour.c, tests/test-gc-arctwo.c, tests/test-gc-des.c: * tests/test-gc-hmac-md5.c, tests/test-gc-hmac-sha1.c: * tests/test-gc-md2.c, tests/test-gc-md4.c, tests/test-gc-md5.c: * tests/test-gc-pbkdf2-sha1.c, tests/test-gc-rijndael.c: * tests/test-gc-sha1.c, tests/test-gc.c, tests/test-getdelim.c: * tests/test-getline.c, tests/test-getndelim2.c, tests/test-md2.c: * tests/test-md4.c, tests/test-parse-datetime.c, tests/test-perror.c: * tests/test-perror2.c, tests/test-pipe.c, tests/test-pipe2.c: * tests/test-poll.c, tests/test-quotearg-simple.c: * tests/test-quotearg.c, tests/test-quotearg.h: * tests/test-round-ieee.c, tests/test-round1.c: * tests/test-roundf-ieee.c, tests/test-roundf1.c: * tests/test-roundl-ieee.c, tests/test-roundl.c: * tests/test-safe-alloc.c, tests/test-sigpipe.c: * tests/test-spawn-pipe-child.c, tests/test-spawn-pipe-main.c: * tests/test-strerror.c, tests/test-strerror_r.c: * tests/test-strsignal.c, tests/test-strverscmp.c: * tests/test-xmemdup0.c: Replace FSF snail mail addresses with URLs, as per GNU coding standards. See glibc bug <http://sourceware.org/bugzilla/show_bug.cgi?id=13673>.
Jim Meyering 1602f0af 2012-01-01T10:04:58 maint: update all copyright year number ranges Run "make update-copyright".
Eric Blake 034c875d 2011-02-25T09:10:57 strstr: revert patches that introduced bug and pessimization Jim's one-liner solved the bug by pessimizing speed, making the algorithm shift less per iteration and thus perform more repeated comparisons. The real reason for the bug is that my supposed "optimizations" actually resulted in cases on certain periodic needles where critical_factorization returned a factorization that was equal to, rather than less than the period of the needle. This makes the CMP_FUNC choose the wrong branch, since a periodic needle must be handled differently than one where the left half of the needle does not overlap the right half. Thankfully, the flawed "optimization" was only present in gnulib, and was never ported to glibc or cygwin (the only two known implementations that use the two-way algorithm), so no additional m4 check is needed to detect the bug in the wild. * lib/str-two-way.h: Add another reference. (two_way_short_needle, two_way_long_needle): Revert changes from 2011-02-24; they pessimize search speed. (critical_factorization): Partially revert changes from 2010-06-22; they violate the requirement that the left half of the needle be smaller than the period of the needle. Signed-off-by: Eric Blake <eblake@redhat.com>
Jim Meyering 98d62d70 2011-02-24T10:57:22 strstr: fix a bug whereby strstr would mistakenly return NULL * lib/str-two-way.h (two_way_short_needle): Correct off-by-one error in period calculation. (two_way_long_needle): Likewise. Reported by Ralf Wildenhues, with the short needle and haystack. * tests/test-strstr.c: Add Ralf's test case to trigger the bug. Add a more involved test to trigger the bug in two_way_long_needle.
Jim Meyering d60f3b0c 2011-01-01T20:17:23 maint: update almost all copyright ranges to include 2011 Run the new "make update-copyright" rule.
Eric Blake c823199d 2010-10-05T16:39:32 memmem, strstr, strcasestr: fix bug with long periodic needle * lib/str-two-way.h (two_way_long_needle): Avoid bug with long periodic needle having false positive. * m4/memmem.m4 (gl_FUNC_MEMMEM_SIMPLE): Detect bug in glibc 2.12 and cygwin 1.7.7. (gl_FUNC_MEMMEM): Be more pessimistic when cross-compiling. * m4/strcasestr.m4 (gl_FUNC_STRCASESTR_SIMPLE) (gl_FUNC_STRCASESTR): Likewise. * m4/strstr.m4 (gl_FUNC_STRSTR_SIMPLE, gl_FUNC_STRSTR): Likewise. * tests/test-memmem.c (main): Expose the bug. * tests/test-strcasestr.c (main): Likewise. * tests/test-strstr.c (main): Likewise. * tests/test-c-strcasestr.c (main): Likewise. * doc/glibc-functions/memmem.texi (memmem): Document the bug. * doc/posix-functions/strstr.texi (strstr): Likewise. * doc/glibc-functions/strcasestr.texi (strcasestr): Likewise. Reported via http://sourceware.org/bugzilla/show_bug.cgi?id=12092 Signed-off-by: Eric Blake <eblake@redhat.com>
Eric Blake fffd5fac 2010-06-21T16:16:44 memmem: slight optimization For any needle, the factorization 0/n has a local period of 1, so it is a critical factorization iff the entire needle consists only of a single repeated byte, in which case 1/n-1 would also be critical. Starting with a comparison of x[0] and x[1] in the maximal suffix check will either find the 0/n case or move on to something else, so we can optimize and start with the x[1] vs. x[2] case to begin with. To avoid out-of-bounds references, we must then special case needles of length two or less. However, for these cases, we can determine a critical factorization without any probes of the needle (we already require a non-empty needle; a 1-byte needle can factor as either 0/1 or 1/0 but the rest of our code assumes a non-empty suffix; and of the two 2-byte needle patterns, "aa" can factor as either 0/2 or 1/1 but with best performance for 1/1, and "ab" must be factored as 1/1). * lib/str-two-way.h (critical_factorization): Update comments. Reduce work during factorization phase. Reported by Carlos Bueno <carlos@bueno.org>. Signed-off-by: Eric Blake <eblake@redhat.com>
Jim Meyering b2e2010c 2010-01-01T10:31:12 update nearly all FSF copyright year lists to include 2010 Use the same procedure as for 2009, outlined in http://thread.gmane.org/gmane.comp.lib.gnulib.bugs/20081
Jim Meyering 3030c5b5 2009-12-28T10:50:36 update nearly all FSF copyright year lists to include 2009 The files named by the following are exempted: grep -v '^#' config/srclist.txt|grep -v '^$' \ | while read src dst; do test -f "$dst" && { echo "$dst"; continue; } test -d "$dst" || continue echo "$dst"/$(basename "$src") done > exempt git ls-files tests/unictype >> exempt In the remaining files, convert to all-interval notation if - there is already at least one year interval like 2000-2003 - the file is maintained by me - the file is in lib/uni*/, where that style already prevails Otherwise, use update-copyright's default.
Bruno Haible 441aa304 2009-12-10T20:28:30 Use spaces for indentation, not tabs.
Eric Blake a3721792 2008-05-15T06:16:11 Glibc finally accepted the memmem speedup code, bugzilla #5514. * doc/glibc-functions/memmem.texi (memmem): Mention last broken glibc version. * doc/glibc-functions/strcasestr.texi (strcasestr): Likewise. * doc/posix-functions/strstr.texi (strstr): Likewise. * lib/str-two-way.h (MAX): Sychronize with glibc. Signed-off-by: Eric Blake <ebb9@byu.net>
Eric Blake 9c063a2a 2008-01-10T22:22:51 Convert strcasestr module to use Two-Way algorithm. * modules/strcasestr-simple: New module, based on the old strcasestr, but with Two-Way rather than KMP. * modules/strcasestr (Depends-on): Change to strcasestr-simple. * lib/string.in.h (rpl_strcasestr): Declare. * m4/strcasestr.m4 (gl_FUNC_STRCASESTR): Check for linear performance. * lib/strcasestr.c (strcasestr): Simplify, and avoid malloc. * modules/string (Makefile.am): Support strcasestr. * m4/string_h.m4 (gl_HEADER_STRING_H_DEFAULTS): Likewise. * modules/strcasestr-tests (Depends-on): Check for alarm. * tests/test-strcasestr.c: Augment test. * lib/str-two-way.h: Clean up stray macro. * NEWS: Document new module. * MODULES.html.sh (string handling): Likewise. * doc/functions/strcasestr.texi: New file. * doc/gnulib.texi (Function Substitutes): New node. Move memmem here, since it is not a POSIX function. Signed-off-by: Eric Blake <ebb9@byu.net>
Eric Blake c358da1e 2008-01-10T12:06:35 Share two-way algorithm. * lib/str-two-way.h: New file, merged from... * lib/memmem.c: ...here... * lib/strstr.c: ...and here. * modules/memmem (Files): Use it. * modules/strstr (Files): Likewise. Signed-off-by: Eric Blake <ebb9@byu.net>