mirror of
https://github.com/git/git.git
synced 2024-10-31 06:17:56 +01:00
951f316470
Provide macros to generate a type-specific treap implementation and various functions to operate on it. It uses obj_pool.h to store memory nodes in a treap. Previously committed nodes are never removed from the pool; after any *_commit operation, it is assumed (correctly, in the case of svn-fast-export) that someone else must care about them. Treaps provide a memory-efficient binary search tree structure. Insertion/deletion/search are about as about as fast in the average case as red-black trees and the chances of worst-case behavior are vanishingly small, thanks to (pseudo-)randomness. The bad worst-case behavior is a small price to pay, given that treaps are much simpler to implement. >From http://www.canonware.com/download/trp/trp_hash/trp.h [db: Altered to reference nodes by offset from a common base pointer] [db: Bob Jenkins' hashing implementation dropped for Knuth's] [db: Methods unnecessary for search and insert dropped] [rr: Squelched compiler warnings] [db: Added support for immutable treap nodes] [jn: Reintroduced treap_nsearch(); with tests] Signed-off-by: David Barr <david.barr@cordelta.com> Signed-off-by: Ramkumar Ramachandra <artagnon@gmail.com> Signed-off-by: Jonathan Nieder <jrnieder@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
65 lines
1.5 KiB
C
65 lines
1.5 KiB
C
/*
|
|
* test-treap.c: code to exercise the svn importer's treap structure
|
|
*/
|
|
|
|
#include "cache.h"
|
|
#include "vcs-svn/obj_pool.h"
|
|
#include "vcs-svn/trp.h"
|
|
|
|
struct int_node {
|
|
uintmax_t n;
|
|
struct trp_node children;
|
|
};
|
|
|
|
obj_pool_gen(node, struct int_node, 3)
|
|
|
|
static int node_cmp(struct int_node *a, struct int_node *b)
|
|
{
|
|
return (a->n > b->n) - (a->n < b->n);
|
|
}
|
|
|
|
trp_gen(static, treap_, struct int_node, children, node, node_cmp)
|
|
|
|
static void strtonode(struct int_node *item, const char *s)
|
|
{
|
|
char *end;
|
|
item->n = strtoumax(s, &end, 10);
|
|
if (*s == '\0' || (*end != '\n' && *end != '\0'))
|
|
die("invalid integer: %s", s);
|
|
}
|
|
|
|
int main(int argc, char *argv[])
|
|
{
|
|
struct strbuf sb = STRBUF_INIT;
|
|
struct trp_root root = { ~0 };
|
|
uint32_t item;
|
|
|
|
if (argc != 1)
|
|
usage("test-treap < ints");
|
|
|
|
while (strbuf_getline(&sb, stdin, '\n') != EOF) {
|
|
item = node_alloc(1);
|
|
strtonode(node_pointer(item), sb.buf);
|
|
treap_insert(&root, node_pointer(item));
|
|
}
|
|
|
|
item = node_offset(treap_first(&root));
|
|
while (~item) {
|
|
uint32_t next;
|
|
struct int_node *tmp = node_pointer(node_alloc(1));
|
|
|
|
tmp->n = node_pointer(item)->n;
|
|
next = node_offset(treap_next(&root, node_pointer(item)));
|
|
|
|
treap_remove(&root, node_pointer(item));
|
|
item = node_offset(treap_nsearch(&root, tmp));
|
|
|
|
if (item != next && (!~item || node_pointer(item)->n != tmp->n))
|
|
die("found %"PRIuMAX" in place of %"PRIuMAX"",
|
|
~item ? node_pointer(item)->n : ~(uintmax_t) 0,
|
|
~next ? node_pointer(next)->n : ~(uintmax_t) 0);
|
|
printf("%"PRIuMAX"\n", tmp->n);
|
|
}
|
|
node_reset();
|
|
return 0;
|
|
}
|