| /* vi: set sw=4 ts=4: */ |
| /* |
| * Utility routines. |
| * |
| * Copyright (C) many different people. |
| * If you wrote this, please acknowledge your work. |
| * |
| * Licensed under GPLv2 or later, see file LICENSE in this source tree. |
| */ |
| |
| #include "libbb.h" |
| |
| typedef struct ino_dev_hash_bucket_struct { |
| ino_t ino; |
| dev_t dev; |
| /* |
| * Above fields can be 64-bit, while pointer may be 32-bit. |
| * Putting "next" field here may reduce size of this struct: |
| */ |
| struct ino_dev_hash_bucket_struct *next; |
| /* |
| * Reportedly, on cramfs a file and a dir can have same ino. |
| * Need to also remember "file/dir" bit: |
| */ |
| char isdir; /* bool */ |
| char name[1]; |
| } ino_dev_hashtable_bucket_t; |
| |
| #define HASH_SIZE 311u /* Should be prime */ |
| #define hash_inode(i) ((unsigned)(i) % HASH_SIZE) |
| |
| /* array of [HASH_SIZE] elements */ |
| static ino_dev_hashtable_bucket_t **ino_dev_hashtable; |
| |
| /* |
| * Return name if statbuf->st_ino && statbuf->st_dev are recorded in |
| * ino_dev_hashtable, else return NULL |
| */ |
| char* FAST_FUNC is_in_ino_dev_hashtable(const struct stat *statbuf) |
| { |
| ino_dev_hashtable_bucket_t *bucket; |
| |
| if (!ino_dev_hashtable) |
| return NULL; |
| |
| bucket = ino_dev_hashtable[hash_inode(statbuf->st_ino)]; |
| while (bucket != NULL) { |
| if ((bucket->ino == statbuf->st_ino) |
| && (bucket->dev == statbuf->st_dev) |
| && (bucket->isdir == !!S_ISDIR(statbuf->st_mode)) |
| ) { |
| return bucket->name; |
| } |
| bucket = bucket->next; |
| } |
| return NULL; |
| } |
| |
| /* Add statbuf to statbuf hash table */ |
| void FAST_FUNC add_to_ino_dev_hashtable(const struct stat *statbuf, const char *name) |
| { |
| int i; |
| ino_dev_hashtable_bucket_t *bucket; |
| |
| if (!name) |
| name = ""; |
| bucket = xmalloc(sizeof(ino_dev_hashtable_bucket_t) + strlen(name)); |
| bucket->ino = statbuf->st_ino; |
| bucket->dev = statbuf->st_dev; |
| bucket->isdir = !!S_ISDIR(statbuf->st_mode); |
| strcpy(bucket->name, name); |
| |
| if (!ino_dev_hashtable) |
| ino_dev_hashtable = xzalloc(HASH_SIZE * sizeof(*ino_dev_hashtable)); |
| |
| i = hash_inode(statbuf->st_ino); |
| bucket->next = ino_dev_hashtable[i]; |
| ino_dev_hashtable[i] = bucket; |
| } |
| |
| #if ENABLE_DU || ENABLE_FEATURE_CLEAN_UP |
| /* Clear statbuf hash table */ |
| void FAST_FUNC reset_ino_dev_hashtable(void) |
| { |
| int i; |
| ino_dev_hashtable_bucket_t *bucket, *next; |
| |
| if (!ino_dev_hashtable) |
| return; |
| |
| for (i = 0; i < HASH_SIZE; i++) { |
| bucket = ino_dev_hashtable[i]; |
| |
| while (bucket != NULL) { |
| next = bucket->next; |
| free(bucket); |
| bucket = next; |
| } |
| } |
| free(ino_dev_hashtable); |
| ino_dev_hashtable = NULL; |
| } |
| #endif |