From 33f7405bf554e75bfc7fa245d51f1b45020fb843 Mon Sep 17 00:00:00 2001 From: Robert James Kaes Date: Tue, 3 May 2005 20:34:54 +0000 Subject: [PATCH] * [1118363] Proxy reverse order of headers Changed the internal implementation of the hashmap to maintain the insert order if the same key is repeated. The insertion is still constant since we keep track of the head and tail of the bucket chain. Signed-off-by: Michael Adam --- src/hashmap.c | 80 ++++++++++++++++++++++++++------------------------- 1 file changed, 41 insertions(+), 39 deletions(-) diff --git a/src/hashmap.c b/src/hashmap.c index 4f7773d..0ce1073 100644 --- a/src/hashmap.c +++ b/src/hashmap.c @@ -44,11 +44,16 @@ struct hashentry_s { struct hashentry_s *prev, *next; }; + +struct hashbucket_s { + struct hashentry_s *head, *tail; +}; + struct hashmap_s { unsigned int size; hashmap_iter end_iterator; - struct hashentry_s **buckets; + struct hashbucket_s *buckets; }; /* @@ -102,7 +107,7 @@ hashmap_create(unsigned int nbuckets) return NULL; ptr->size = nbuckets; - ptr->buckets = safecalloc(nbuckets, sizeof(struct hashentry_s *)); + ptr->buckets = safecalloc(nbuckets, sizeof(struct hashbucket_s)); if (!ptr->buckets) { safefree(ptr); return NULL; @@ -122,15 +127,15 @@ hashmap_create(unsigned int nbuckets) * negative number is returned if "entry" was NULL */ static inline int -delete_hashbucket(struct hashentry_s* entry) +delete_hashbucket(struct hashbucket_s* bucket) { struct hashentry_s *nextptr; struct hashentry_s *ptr; - if (entry == NULL) + if (bucket == NULL || bucket->head == NULL) return -EINVAL; - ptr = entry; + ptr = bucket->head; while (ptr) { nextptr = ptr->next; @@ -159,9 +164,8 @@ hashmap_delete(hashmap_t map) return -EINVAL; for (i = 0; i != map->size; i++) { - if (map->buckets[i] != NULL) { - delete_hashbucket(map->buckets[i]); - map->buckets[i] = NULL; + if (map->buckets[i].head != NULL) { + delete_hashbucket(&map->buckets[i]); } } @@ -234,15 +238,17 @@ hashmap_insert(hashmap_t map, const char *key, ptr->data = data_copy; ptr->len = len; - /* - * Put the entry at the beginning of the chain. This is a constant - * time insert. Thanks to Justin Guyett for the code. - */ - ptr->prev = NULL; - ptr->next = map->buckets[hash]; - map->buckets[hash] = ptr; - if (ptr->next) - ptr->next->prev = ptr; + /* + * Now add the entry to the end of the bucket chain. + */ + ptr->next = NULL; + ptr->prev = map->buckets[hash].tail; + if (map->buckets[hash].tail) + map->buckets[hash].tail->next = ptr; + + map->buckets[hash].tail = ptr; + if (!map->buckets[hash].head) + map->buckets[hash].head = ptr; map->end_iterator++; return 0; @@ -314,7 +320,7 @@ hashmap_find(hashmap_t map, const char* key) * of a particular key. */ for (i = 0; i != map->size; i++) { - ptr = map->buckets[i]; + ptr = map->buckets[i].head; while (ptr) { if (strcasecmp(ptr->key, key) == 0) { @@ -354,7 +360,7 @@ hashmap_return_entry(hashmap_t map, hashmap_iter iter, return -EINVAL; for (i = 0; i != map->size; i++) { - ptr = map->buckets[i]; + ptr = map->buckets[i].head; while (ptr) { if (count == iter) { /* This is the data so return it */ @@ -392,7 +398,7 @@ hashmap_search(hashmap_t map, const char *key) if (hash < 0) return hash; - ptr = map->buckets[hash]; + ptr = map->buckets[hash].head; /* All right, there is an entry here, now see if it's the one we want */ while (ptr) { @@ -427,7 +433,7 @@ hashmap_entry_by_key(hashmap_t map, const char* key, void** data) if (hash < 0) return hash; - ptr = map->buckets[hash]; + ptr = map->buckets[hash].head; while (ptr) { if (strcasecmp(ptr->key, key) == 0) { @@ -453,7 +459,7 @@ ssize_t hashmap_remove(hashmap_t map, const char *key) { int hash; - struct hashentry_s* ptr; + struct hashentry_s *ptr, *next; short int deleted = 0; if (map == NULL || key == NULL) @@ -463,25 +469,25 @@ hashmap_remove(hashmap_t map, const char *key) if (hash < 0) return hash; - ptr = map->buckets[hash]; + ptr = map->buckets[hash].head; while (ptr) { if (strcasecmp(ptr->key, key) == 0) { /* * Found the data, now need to remove everything * and update the hashmap. */ - struct hashentry_s* prevptr = ptr->prev; - if (prevptr != NULL) { - prevptr->next = ptr->next; - if (ptr->next) - ptr->next->prev = prevptr; - } else { - /* Entry was first in map */ - map->buckets[hash] = ptr->next; - if (ptr->next) - ptr->next->prev = NULL; - } + next = ptr->next; + + if (ptr->prev) + ptr->prev->next = ptr->next; + if (ptr->next) + ptr->next->prev = ptr->prev; + if (map->buckets[hash].head == ptr) + map->buckets[hash].head = ptr->next; + if (map->buckets[hash].tail == ptr) + map->buckets[hash].tail = ptr->prev; + safefree(ptr->key); safefree(ptr->data); safefree(ptr); @@ -489,11 +495,7 @@ hashmap_remove(hashmap_t map, const char *key) ++deleted; --map->end_iterator; - if (prevptr) - ptr = prevptr; - else - ptr = map->buckets[hash]; - + ptr = next; continue; }