From eb8dd9dca1228af0cd132f515509051ecfabf6f6 Mon Sep 17 00:00:00 2001 From: cvs2svn Date: Mon, 14 Apr 2025 17:32:06 +0000 Subject: This commit was manufactured by cvs2git to create tag 'tb_20250414'. --- src/lib/libc/string/strstr.c | 189 ------------------------------------------- 1 file changed, 189 deletions(-) delete mode 100644 src/lib/libc/string/strstr.c (limited to 'src/lib/libc/string/strstr.c') diff --git a/src/lib/libc/string/strstr.c b/src/lib/libc/string/strstr.c deleted file mode 100644 index 241a080e7a..0000000000 --- a/src/lib/libc/string/strstr.c +++ /dev/null @@ -1,189 +0,0 @@ -/* $OpenBSD: strstr.c,v 1.9 2020/04/16 12:37:52 claudio Exp $ */ - -/* - * Copyright (c) 2005-2018 Rich Felker - * - * Permission is hereby granted, free of charge, to any person obtaining - * a copy of this software and associated documentation files (the - * "Software"), to deal in the Software without restriction, including - * without limitation the rights to use, copy, modify, merge, publish, - * distribute, sublicense, and/or sell copies of the Software, and to - * permit persons to whom the Software is furnished to do so, subject to - * the following conditions: - * - * The above copyright notice and this permission notice shall be - * included in all copies or substantial portions of the Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, - * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF - * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. - * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY - * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, - * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE - * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. - */ - -#include -#include - -static char * -twobyte_strstr(const unsigned char *h, const unsigned char *n) -{ - uint16_t nw = n[0]<<8 | n[1], hw = h[0]<<8 | h[1]; - for (h++; *h && hw != nw; hw = hw<<8 | *++h); - return *h ? (char *)h-1 : 0; -} - -static char * -threebyte_strstr(const unsigned char *h, const unsigned char *n) -{ - uint32_t nw = n[0]<<24 | n[1]<<16 | n[2]<<8; - uint32_t hw = h[0]<<24 | h[1]<<16 | h[2]<<8; - for (h+=2; *h && hw != nw; hw = (hw|*++h)<<8); - return *h ? (char *)h-2 : 0; -} - -static char * -fourbyte_strstr(const unsigned char *h, const unsigned char *n) -{ - uint32_t nw = n[0]<<24 | n[1]<<16 | n[2]<<8 | n[3]; - uint32_t hw = h[0]<<24 | h[1]<<16 | h[2]<<8 | h[3]; - for (h+=3; *h && hw != nw; hw = hw<<8 | *++h); - return *h ? (char *)h-3 : 0; -} - -#define MAX(a,b) ((a)>(b)?(a):(b)) -#define MIN(a,b) ((a)<(b)?(a):(b)) - -#define BITOP(a,b,op) \ - ((a)[(size_t)(b)/(8*sizeof *(a))] op (size_t)1<<((size_t)(b)%(8*sizeof *(a)))) - -/* - * Maxime Crochemore and Dominique Perrin, Two-way string-matching, - * Journal of the ACM, 38(3):651-675, July 1991. - */ -static char * -twoway_strstr(const unsigned char *h, const unsigned char *n) -{ - const unsigned char *z; - size_t l, ip, jp, k, p, ms, p0, mem, mem0; - size_t byteset[32 / sizeof(size_t)] = { 0 }; - size_t shift[256]; - - /* Computing length of needle and fill shift table */ - for (l=0; n[l] && h[l]; l++) - BITOP(byteset, n[l], |=), shift[n[l]] = l+1; - if (n[l]) return 0; /* hit the end of h */ - - /* Compute maximal suffix */ - ip = -1; jp = 0; k = p = 1; - while (jp+k n[jp+k]) { - jp += k; - k = 1; - p = jp - ip; - } else { - ip = jp++; - k = p = 1; - } - } - ms = ip; - p0 = p; - - /* And with the opposite comparison */ - ip = -1; jp = 0; k = p = 1; - while (jp+k ms+1) ms = ip; - else p = p0; - - /* Periodic needle? */ - if (memcmp(n, n+p, ms+1)) { - mem0 = 0; - p = MAX(ms, l-ms-1) + 1; - } else mem0 = l-p; - mem = 0; - - /* Initialize incremental end-of-haystack pointer */ - z = h; - - /* Search loop */ - for (;;) { - /* Update incremental end-of-haystack pointer */ - if (z-h < l) { - /* Fast estimate for MIN(l,63) */ - size_t grow = l | 63; - const unsigned char *z2 = memchr(z, 0, grow); - if (z2) { - z = z2; - if (z-h < l) return 0; - } else z += grow; - } - - /* Check last byte first; advance by shift on mismatch */ - if (BITOP(byteset, h[l-1], &)) { - k = l-shift[h[l-1]]; - if (k) { - if (k < mem) k = mem; - h += k; - mem = 0; - continue; - } - } else { - h += l; - mem = 0; - continue; - } - - /* Compare right half */ - for (k=MAX(ms+1,mem); n[k] && n[k] == h[k]; k++); - if (n[k]) { - h += k-ms; - mem = 0; - continue; - } - /* Compare left half */ - for (k=ms+1; k>mem && n[k-1] == h[k-1]; k--); - if (k <= mem) return (char *)h; - h += p; - mem = mem0; - } -} - -char * -strstr(const char *h, const char *n) -{ - /* Return immediately on empty needle */ - if (!n[0]) return (char *)h; - - /* Use faster algorithms for short needles */ - h = strchr(h, *n); - if (!h || !n[1]) return (char *)h; - if (!h[1]) return 0; - if (!n[2]) return twobyte_strstr((void *)h, (void *)n); - if (!h[2]) return 0; - if (!n[3]) return threebyte_strstr((void *)h, (void *)n); - if (!h[3]) return 0; - if (!n[4]) return fourbyte_strstr((void *)h, (void *)n); - - return twoway_strstr((void *)h, (void *)n); -} -DEF_STRONG(strstr); -- cgit v1.2.3-55-g6feb