diff options
Diffstat (limited to 'busybox/libbb/inode_hash.c')
-rw-r--r-- | busybox/libbb/inode_hash.c | 111 |
1 files changed, 111 insertions, 0 deletions
diff --git a/busybox/libbb/inode_hash.c b/busybox/libbb/inode_hash.c new file mode 100644 index 0000000..fbcd813 --- /dev/null +++ b/busybox/libbb/inode_hash.c @@ -0,0 +1,111 @@ +/* vi: set sw=4 ts=4: */ +/* + * Utility routines. + * + * Copyright (C) many different people. + * If you wrote this, please acknowledge your work. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program 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 + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 + * USA + */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include "libbb.h" + +#define HASH_SIZE 311 /* Should be prime */ +#define hash_inode(i) ((i) % HASH_SIZE) + +typedef struct ino_dev_hash_bucket_struct { + struct ino_dev_hash_bucket_struct *next; + ino_t ino; + dev_t dev; + char name[1]; +} ino_dev_hashtable_bucket_t; + +static ino_dev_hashtable_bucket_t *ino_dev_hashtable[HASH_SIZE]; + +/* + * Return 1 if statbuf->st_ino && statbuf->st_dev are recorded in + * `ino_dev_hashtable', else return 0 + * + * If NAME is a non-NULL pointer to a character pointer, and there is + * a match, then set *NAME to the value of the name slot in that + * bucket. + */ +int is_in_ino_dev_hashtable(const struct stat *statbuf, char **name) +{ + ino_dev_hashtable_bucket_t *bucket; + + bucket = ino_dev_hashtable[hash_inode(statbuf->st_ino)]; + while (bucket != NULL) { + if ((bucket->ino == statbuf->st_ino) && + (bucket->dev == statbuf->st_dev)) + { + if (name) *name = bucket->name; + return 1; + } + bucket = bucket->next; + } + return 0; +} + +/* Add statbuf to statbuf hash table */ +void add_to_ino_dev_hashtable(const struct stat *statbuf, const char *name) +{ + int i; + size_t s; + ino_dev_hashtable_bucket_t *bucket; + + i = hash_inode(statbuf->st_ino); + s = name ? strlen(name) : 0; + bucket = xmalloc(sizeof(ino_dev_hashtable_bucket_t) + s); + bucket->ino = statbuf->st_ino; + bucket->dev = statbuf->st_dev; + if (name) + strcpy(bucket->name, name); + else + bucket->name[0] = '\0'; + bucket->next = ino_dev_hashtable[i]; + ino_dev_hashtable[i] = bucket; +} + +#ifdef CONFIG_FEATURE_CLEAN_UP +/* Clear statbuf hash table */ +void reset_ino_dev_hashtable(void) +{ + int i; + ino_dev_hashtable_bucket_t *bucket; + + for (i = 0; i < HASH_SIZE; i++) { + while (ino_dev_hashtable[i] != NULL) { + bucket = ino_dev_hashtable[i]->next; + free(ino_dev_hashtable[i]); + ino_dev_hashtable[i] = bucket; + } + } +} +#endif + + +/* END CODE */ +/* +Local Variables: +c-file-style: "linux" +c-basic-offset: 4 +tab-width: 4 +End: +*/ |