Current Path : /usr/src/libexec/mknetid/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
Current File : //usr/src/libexec/mknetid/hash.c |
/* * Copyright (c) 1995 * Bill Paul <wpaul@ctr.columbia.edu>. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Bill Paul. * 4. Neither the name of the author nor the names of any co-contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY Bill Paul AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL Bill Paul OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <sys/types.h> #include "hash.h" #ifndef lint static const char rcsid[] = "$FreeBSD: release/9.1.0/libexec/mknetid/hash.c 108470 2002-12-30 21:18:15Z schweikh $"; #endif /* not lint */ /* * This hash function is stolen directly from the * Berkeley DB package. It already exists inside libc, but * it's declared static which prevents us from calling it * from here. */ /* * OZ's original sdbm hash */ u_int32_t hash(const void *keyarg, size_t len) { const u_char *key; size_t loop; u_int32_t h; #define HASHC h = *key++ + 65599 * h h = 0; key = keyarg; if (len > 0) { loop = (len + 8 - 1) >> 3; switch (len & (8 - 1)) { case 0: do { HASHC; /* FALLTHROUGH */ case 7: HASHC; /* FALLTHROUGH */ case 6: HASHC; /* FALLTHROUGH */ case 5: HASHC; /* FALLTHROUGH */ case 4: HASHC; /* FALLTHROUGH */ case 3: HASHC; /* FALLTHROUGH */ case 2: HASHC; /* FALLTHROUGH */ case 1: HASHC; } while (--loop); } } return (h); } /* * Generate a hash value for a given key (character string). * We mask off all but the lower 8 bits since our table array * can only hole 256 elements. */ u_int32_t hashkey(char *key) { if (key == NULL) return (-1); return(hash((void *)key, strlen(key)) & HASH_MASK); } /* Find an entry in the hash table (may be hanging off a linked list). */ struct grouplist *lookup(struct member_entry *table[], char *key) { struct member_entry *cur; cur = table[hashkey(key)]; while (cur) { if (!strcmp(cur->key, key)) return(cur->groups); cur = cur->next; } return(NULL); } struct grouplist dummy = { 99999, NULL }; /* * Store a group member entry and/or update its grouplist. */ void mstore (struct member_entry *table[], char *key, int gid, int dup) { struct member_entry *cur, *new; struct grouplist *tmp; u_int32_t i; i = hashkey(key); cur = table[i]; if (!dup) { tmp = (struct grouplist *)malloc(sizeof(struct grouplist)); tmp->groupid = gid; tmp->next = NULL; } /* Check if all we have to do is insert a new groupname. */ while (cur) { if (!dup && !strcmp(cur->key, key)) { tmp->next = cur->groups; cur->groups = tmp; return; } cur = cur->next; } /* Didn't find a match -- add the whole mess to the table. */ new = (struct member_entry *)malloc(sizeof(struct member_entry)); new->key = strdup(key); if (!dup) new->groups = tmp; else new->groups = (struct grouplist *)&dummy; new->next = table[i]; table[i] = new; return; }