X-Git-Url: https://pd.if.org/git/?p=nbds;a=blobdiff_plain;f=map%2Flist.c;h=f2e9c82c0e65fe85888721bed1145947af79ef73;hp=ac6b6a570feebffd751b5795e588b3903269747b;hb=329b5ab58cde015f4faec1879d3106f635294dd6;hpb=9d72edf41ce3a2ddbbe2d44afc23ef5ec53339c3 diff --git a/map/list.c b/map/list.c index ac6b6a5..f2e9c82 100644 --- a/map/list.c +++ b/map/list.c @@ -13,11 +13,13 @@ #include "list.h" #include "mem.h" -typedef struct node { +typedef struct ll_iter node_t; + +struct ll_iter { void *key; uint64_t val; - struct node *next; -} node_t; + node_t *next; +}; struct ll { node_t *head; @@ -42,7 +44,7 @@ list_t *ll_alloc (const datatype_t *key_type) { void ll_free (list_t *ll) { node_t *item = ll->head->next; while (item) { - node_t *next = (node_t *)STRIP_TAG(item->next); + node_t *next = (node_t *)STRIP_TAG(item->next, TAG1); nbd_free(item); item = next; } @@ -52,8 +54,10 @@ uint64_t ll_count (list_t *ll) { uint64_t count = 0; node_t *item = ll->head->next; while (item) { - count++; - item = (node_t *)STRIP_TAG(item->next); + if (!IS_TAGGED(item->next, TAG1)) { + count++; + } + item = (node_t *)STRIP_TAG(item->next, TAG1); } return count; } @@ -67,11 +71,11 @@ static int find_pred (node_t **pred_ptr, node_t **item_ptr, list_t *ll, void *ke node_t *next = item->next; // A tag means an item is logically removed but not physically unlinked yet. - while (EXPECT_FALSE(IS_TAGGED(next))) { + while (EXPECT_FALSE(IS_TAGGED(next, TAG1))) { // Skip over logically removed items. if (!help_remove) { - item = (node_t *)STRIP_TAG(item->next); + item = (node_t *)STRIP_TAG(item->next, TAG1); if (EXPECT_FALSE(item == NULL)) break; TRACE("l3", "find_pred: skipping marked item %p (next is %p)", item, next); @@ -82,9 +86,9 @@ static int find_pred (node_t **pred_ptr, node_t **item_ptr, list_t *ll, void *ke // Unlink logically removed items. node_t *other; TRACE("l3", "find_pred: unlinking marked item %p next is %p", item, next); - if ((other = SYNC_CAS(&pred->next, item, STRIP_TAG(next))) == item) { + if ((other = SYNC_CAS(&pred->next, item, STRIP_TAG(next, TAG1))) == item) { TRACE("l2", "find_pred: unlinked item %p from pred %p", item, pred); - item = (node_t *)STRIP_TAG(next); + item = (node_t *)STRIP_TAG(next, TAG1); if (EXPECT_FALSE(item == NULL)) break; next = item->next; @@ -98,7 +102,7 @@ static int find_pred (node_t **pred_ptr, node_t **item_ptr, list_t *ll, void *ke } else { TRACE("l2", "find_pred: lost a race to unlink item %p from pred %p", item, pred); TRACE("l2", "find_pred: pred's link changed to %p", other, 0); - if (IS_TAGGED(other)) + if (IS_TAGGED(other, TAG1)) return find_pred(pred_ptr, item_ptr, ll, key, help_remove); // retry item = other; if (EXPECT_FALSE(item == NULL)) @@ -250,14 +254,14 @@ uint64_t ll_remove (list_t *ll, void *key) { node_t *old_next = item->next; do { next = old_next; - old_next = SYNC_CAS(&item->next, next, TAG_VALUE(next)); - if (IS_TAGGED(old_next)) { + old_next = SYNC_CAS(&item->next, next, TAG_VALUE(next, TAG1)); + if (IS_TAGGED(old_next, TAG1)) { TRACE("l1", "ll_remove: lost a race -- %p is already marked for removal by another thread", item, 0); return DOES_NOT_EXIST; } } while (next != old_next); TRACE("l2", "ll_remove: logically removed item %p", item, 0); - ASSERT(IS_TAGGED(item->next)); + ASSERT(IS_TAGGED(item->next, TAG1)); // Atomically swap out the item's value in case another thread is updating the item while we are // removing it. This establishes which operation occurs first logically, the update or the remove. @@ -289,12 +293,12 @@ void ll_print (list_t *ll) { int i = 0; while (item) { node_t *next = item->next; - if (IS_TAGGED(item)) { + if (IS_TAGGED(item, TAG1)) { printf("*"); } printf("%p:%p ", item, item->key); fflush(stdout); - item = (node_t *)STRIP_TAG(next); + item = (node_t *)STRIP_TAG(next, TAG1); if (i++ > 30) { printf("..."); break; @@ -302,3 +306,30 @@ void ll_print (list_t *ll) { } printf("\n"); } + +ll_iter_t *ll_iter_begin (list_t *ll, void *key) { + node_t *iter = node_alloc(0,0); + find_pred(NULL, &iter->next, ll, key, FALSE); + return iter; +} + +uint64_t ll_iter_next (ll_iter_t *iter, void **key_ptr) { + assert(iter); + node_t *item = iter->next; + while (item != NULL && IS_TAGGED(item->next, TAG1)) { + item = (node_t *)STRIP_TAG(item->next, TAG1); + } + if (item == NULL) { + iter->next = NULL; + return DOES_NOT_EXIST; + } + iter->next = item->next; + if (key_ptr != NULL) { + *key_ptr = item->key; + } + return item->val; +} + +void ll_iter_free (ll_iter_t *iter) { + nbd_free(iter); +}