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snapshot v2/p4; _insert done

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Gregory Burd 2024-03-23 11:00:49 -04:00
parent d5b5599c5d
commit 1b97e7b8d9
1 changed files with 42 additions and 2 deletions
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44
include/sl.h
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@ -463,9 +463,49 @@
level = __skip_toss_##decl(slist->max - 1); \
n->field.sle.gen = slist->gen; \
n->field.sle.height = level; \
/* preserve nodes for snapshots if necessary */ \
\
/* preserve nodes for snapshots if necessary \
* \
* ALGORITHM: \
* Foreach node in `path`, if the generation in that element \
* is less than the current generation for the list then \
* that node must be preserved before being mutated for this \
* insert. So we: \
* a) allocate a new node and copy this node into it without \
* copying the user-supplied additional memory (that will \
* happen iff an _update() is called on the node). \
* b) zero out the next sle.prev/next[] pointers \
* c) determine if this is a duplicate, if so we set the \
* sle.next[1] field to 0x1 as a reminder to re-insert \
* this element as a duplicate in the restore function. \
* d) ignore the head and the tail nodes in path[] \
*/ \
for (i = 0; i < len; i++) { \
if (path[i]->field.sle.gen >= slist->max_gen) { \
if (path[i]->field.sle.gen < slist->gen) { \
if (path[i] == slist->slh_head || path[i] == slist->slh_tail) \
continue; \
int rc; \
decl##_node_t *src = node, *dest, *this; \
size_t amt = sizeof(src); \
char *d = NULL; \
const char *s = (const char *)src; \
rc = prefix##skip_alloc_node_##decl(slist, &dest); \
if (rc) \
return rc; \
d = (char *)dest; \
for (size_t i = 0; i < amt; i++) \
d[i] = s[i]; \
\
this = dest; \
this->field.sle.prev = NULL; \
__SKIP_NEXT_ENTRIES_B2T(field, this) \
{ \
this->field.sle.next[lvl] = NULL; \
} \
\
if (__skip_key_compare_##decl(slist, dest, dest->field.sle.next[0], slist->aux) == 0 || \
__skip_key_compare_##decl(slist, dest, dest->field.sle.prev, slist->aux) == 0) \
dest->field.sle.next[0] = (decl##_node_t *)0x1; \
} \
} \
\