vcs-svn: drop treap

This reverts commit 951f316470
(Add treap implementation, 2010-08-09).  The string_pool was
trp.h's last user.

Signed-off-by: David Barr <david.barr@cordelta.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
This commit is contained in:
David Barr 2010-12-13 21:23:17 +11:00 committed by Jonathan Nieder
parent 28c5d9ed2a
commit 5db348dbd5
7 changed files with 2 additions and 445 deletions

1
.gitignore vendored
View File

@ -179,7 +179,6 @@
/test-sigchain
/test-subprocess
/test-svn-fe
/test-treap
/common-cmds.h
*.tar.gz
*.dsc

View File

@ -432,7 +432,6 @@ TEST_PROGRAMS_NEED_X += test-sha1
TEST_PROGRAMS_NEED_X += test-sigchain
TEST_PROGRAMS_NEED_X += test-subprocess
TEST_PROGRAMS_NEED_X += test-svn-fe
TEST_PROGRAMS_NEED_X += test-treap
TEST_PROGRAMS_NEED_X += test-index-version
TEST_PROGRAMS_NEED_X += test-mktemp
@ -1839,7 +1838,7 @@ XDIFF_OBJS = xdiff/xdiffi.o xdiff/xprepare.o xdiff/xutils.o xdiff/xemit.o \
xdiff/xmerge.o xdiff/xpatience.o
VCSSVN_OBJS = vcs-svn/line_buffer.o vcs-svn/repo_tree.o \
vcs-svn/fast_export.o vcs-svn/svndump.o
VCSSVN_TEST_OBJS = test-obj-pool.o test-line-buffer.o test-treap.o
VCSSVN_TEST_OBJS = test-obj-pool.o test-line-buffer.o
OBJECTS := $(GIT_OBJS) $(XDIFF_OBJS) $(VCSSVN_OBJS)
dep_files := $(foreach f,$(OBJECTS),$(dir $f).depend/$(notdir $f).d)
@ -1963,7 +1962,7 @@ xdiff-interface.o $(XDIFF_OBJS): \
xdiff/xutils.h xdiff/xprepare.h xdiff/xdiffi.h xdiff/xemit.h
$(VCSSVN_OBJS) $(VCSSVN_TEST_OBJS): $(LIB_H) \
vcs-svn/obj_pool.h vcs-svn/trp.h \
vcs-svn/obj_pool.h \
vcs-svn/line_buffer.h vcs-svn/repo_tree.h vcs-svn/fast_export.h \
vcs-svn/svndump.h

View File

@ -76,26 +76,4 @@ test_expect_success 'obj pool: high-water mark' '
test_cmp expected actual
'
test_expect_success 'treap sort' '
cat <<-\EOF >unsorted &&
68
12
13
13
68
13
13
21
10
11
12
13
13
EOF
sort unsorted >expected &&
test-treap <unsorted >actual &&
test_cmp expected actual
'
test_done

View File

@ -1,70 +0,0 @@
/*
* 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) {
struct int_node *node = node_pointer(node_alloc(1));
item = node_offset(node);
strtonode(node, sb.buf);
node = treap_insert(&root, node_pointer(item));
if (node_offset(node) != item)
die("inserted %"PRIu32" in place of %"PRIu32"",
node_offset(node), 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;
}

View File

@ -1,9 +1,6 @@
Copyright (C) 2010 David Barr <david.barr@cordelta.com>.
All rights reserved.
Copyright (C) 2008 Jason Evans <jasone@canonware.com>.
All rights reserved.
Copyright (C) 2005 Stefan Hegny, hydrografix Consulting GmbH,
Frankfurt/Main, Germany
and others, see http://svn2cc.sarovar.org

View File

@ -1,237 +0,0 @@
/*
* C macro implementation of treaps.
*
* Usage:
* #include <stdint.h>
* #include "trp.h"
* trp_gen(...)
*
* Licensed under a two-clause BSD-style license.
* See LICENSE for details.
*/
#ifndef TRP_H_
#define TRP_H_
#define MAYBE_UNUSED __attribute__((__unused__))
/* Node structure. */
struct trp_node {
uint32_t trpn_left;
uint32_t trpn_right;
};
/* Root structure. */
struct trp_root {
uint32_t trp_root;
};
/* Pointer/Offset conversion. */
#define trpn_pointer(a_base, a_offset) (a_base##_pointer(a_offset))
#define trpn_offset(a_base, a_pointer) (a_base##_offset(a_pointer))
#define trpn_modify(a_base, a_offset) \
do { \
if ((a_offset) < a_base##_pool.committed) { \
uint32_t old_offset = (a_offset);\
(a_offset) = a_base##_alloc(1); \
*trpn_pointer(a_base, a_offset) = \
*trpn_pointer(a_base, old_offset); \
} \
} while (0)
/* Left accessors. */
#define trp_left_get(a_base, a_field, a_node) \
(trpn_pointer(a_base, a_node)->a_field.trpn_left)
#define trp_left_set(a_base, a_field, a_node, a_left) \
do { \
trpn_modify(a_base, a_node); \
trp_left_get(a_base, a_field, a_node) = (a_left); \
} while (0)
/* Right accessors. */
#define trp_right_get(a_base, a_field, a_node) \
(trpn_pointer(a_base, a_node)->a_field.trpn_right)
#define trp_right_set(a_base, a_field, a_node, a_right) \
do { \
trpn_modify(a_base, a_node); \
trp_right_get(a_base, a_field, a_node) = (a_right); \
} while (0)
/*
* Fibonacci hash function.
* The multiplier is the nearest prime to (2^32 times (5 - 1)/2).
* See Knuth §6.4: volume 3, 3rd ed, p518.
*/
#define trpn_hash(a_node) (uint32_t) (2654435761u * (a_node))
/* Priority accessors. */
#define trp_prio_get(a_node) trpn_hash(a_node)
/* Node initializer. */
#define trp_node_new(a_base, a_field, a_node) \
do { \
trp_left_set(a_base, a_field, (a_node), ~0); \
trp_right_set(a_base, a_field, (a_node), ~0); \
} while (0)
/* Internal utility macros. */
#define trpn_first(a_base, a_field, a_root, r_node) \
do { \
(r_node) = (a_root); \
if ((r_node) == ~0) \
return NULL; \
while (~trp_left_get(a_base, a_field, (r_node))) \
(r_node) = trp_left_get(a_base, a_field, (r_node)); \
} while (0)
#define trpn_rotate_left(a_base, a_field, a_node, r_node) \
do { \
(r_node) = trp_right_get(a_base, a_field, (a_node)); \
trp_right_set(a_base, a_field, (a_node), \
trp_left_get(a_base, a_field, (r_node))); \
trp_left_set(a_base, a_field, (r_node), (a_node)); \
} while (0)
#define trpn_rotate_right(a_base, a_field, a_node, r_node) \
do { \
(r_node) = trp_left_get(a_base, a_field, (a_node)); \
trp_left_set(a_base, a_field, (a_node), \
trp_right_get(a_base, a_field, (r_node))); \
trp_right_set(a_base, a_field, (r_node), (a_node)); \
} while (0)
#define trp_gen(a_attr, a_pre, a_type, a_field, a_base, a_cmp) \
a_attr a_type MAYBE_UNUSED *a_pre##first(struct trp_root *treap) \
{ \
uint32_t ret; \
trpn_first(a_base, a_field, treap->trp_root, ret); \
return trpn_pointer(a_base, ret); \
} \
a_attr a_type MAYBE_UNUSED *a_pre##next(struct trp_root *treap, a_type *node) \
{ \
uint32_t ret; \
uint32_t offset = trpn_offset(a_base, node); \
if (~trp_right_get(a_base, a_field, offset)) { \
trpn_first(a_base, a_field, \
trp_right_get(a_base, a_field, offset), ret); \
} else { \
uint32_t tnode = treap->trp_root; \
ret = ~0; \
while (1) { \
int cmp = (a_cmp)(trpn_pointer(a_base, offset), \
trpn_pointer(a_base, tnode)); \
if (cmp < 0) { \
ret = tnode; \
tnode = trp_left_get(a_base, a_field, tnode); \
} else if (cmp > 0) { \
tnode = trp_right_get(a_base, a_field, tnode); \
} else { \
break; \
} \
} \
} \
return trpn_pointer(a_base, ret); \
} \
a_attr a_type MAYBE_UNUSED *a_pre##search(struct trp_root *treap, a_type *key) \
{ \
int cmp; \
uint32_t ret = treap->trp_root; \
while (~ret && (cmp = (a_cmp)(key, trpn_pointer(a_base, ret)))) { \
if (cmp < 0) { \
ret = trp_left_get(a_base, a_field, ret); \
} else { \
ret = trp_right_get(a_base, a_field, ret); \
} \
} \
return trpn_pointer(a_base, ret); \
} \
a_attr a_type MAYBE_UNUSED *a_pre##nsearch(struct trp_root *treap, a_type *key) \
{ \
int cmp; \
uint32_t ret = treap->trp_root; \
while (~ret && (cmp = (a_cmp)(key, trpn_pointer(a_base, ret)))) { \
if (cmp < 0) { \
if (!~trp_left_get(a_base, a_field, ret)) \
break; \
ret = trp_left_get(a_base, a_field, ret); \
} else { \
ret = trp_right_get(a_base, a_field, ret); \
} \
} \
return trpn_pointer(a_base, ret); \
} \
a_attr uint32_t MAYBE_UNUSED a_pre##insert_recurse(uint32_t cur_node, uint32_t ins_node) \
{ \
if (cur_node == ~0) { \
return ins_node; \
} else { \
uint32_t ret; \
int cmp = (a_cmp)(trpn_pointer(a_base, ins_node), \
trpn_pointer(a_base, cur_node)); \
if (cmp < 0) { \
uint32_t left = a_pre##insert_recurse( \
trp_left_get(a_base, a_field, cur_node), ins_node); \
trp_left_set(a_base, a_field, cur_node, left); \
if (trp_prio_get(left) < trp_prio_get(cur_node)) \
trpn_rotate_right(a_base, a_field, cur_node, ret); \
else \
ret = cur_node; \
} else { \
uint32_t right = a_pre##insert_recurse( \
trp_right_get(a_base, a_field, cur_node), ins_node); \
trp_right_set(a_base, a_field, cur_node, right); \
if (trp_prio_get(right) < trp_prio_get(cur_node)) \
trpn_rotate_left(a_base, a_field, cur_node, ret); \
else \
ret = cur_node; \
} \
return ret; \
} \
} \
a_attr a_type *MAYBE_UNUSED a_pre##insert(struct trp_root *treap, a_type *node) \
{ \
uint32_t offset = trpn_offset(a_base, node); \
trp_node_new(a_base, a_field, offset); \
treap->trp_root = a_pre##insert_recurse(treap->trp_root, offset); \
return trpn_pointer(a_base, offset); \
} \
a_attr uint32_t MAYBE_UNUSED a_pre##remove_recurse(uint32_t cur_node, uint32_t rem_node) \
{ \
int cmp = a_cmp(trpn_pointer(a_base, rem_node), \
trpn_pointer(a_base, cur_node)); \
if (cmp == 0) { \
uint32_t ret; \
uint32_t left = trp_left_get(a_base, a_field, cur_node); \
uint32_t right = trp_right_get(a_base, a_field, cur_node); \
if (left == ~0) { \
if (right == ~0) \
return ~0; \
} else if (right == ~0 || trp_prio_get(left) < trp_prio_get(right)) { \
trpn_rotate_right(a_base, a_field, cur_node, ret); \
right = a_pre##remove_recurse(cur_node, rem_node); \
trp_right_set(a_base, a_field, ret, right); \
return ret; \
} \
trpn_rotate_left(a_base, a_field, cur_node, ret); \
left = a_pre##remove_recurse(cur_node, rem_node); \
trp_left_set(a_base, a_field, ret, left); \
return ret; \
} else if (cmp < 0) { \
uint32_t left = a_pre##remove_recurse( \
trp_left_get(a_base, a_field, cur_node), rem_node); \
trp_left_set(a_base, a_field, cur_node, left); \
return cur_node; \
} else { \
uint32_t right = a_pre##remove_recurse( \
trp_right_get(a_base, a_field, cur_node), rem_node); \
trp_right_set(a_base, a_field, cur_node, right); \
return cur_node; \
} \
} \
a_attr void MAYBE_UNUSED a_pre##remove(struct trp_root *treap, a_type *node) \
{ \
treap->trp_root = a_pre##remove_recurse(treap->trp_root, \
trpn_offset(a_base, node)); \
} \
#endif

View File

@ -1,109 +0,0 @@
Motivation
==========
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.
API
===
The trp API generates a data structure and functions to handle a
large growing set of objects stored in a pool.
The caller:
. Specifies parameters for the generated functions with the
trp_gen(static, foo_, ...) macro.
. Allocates a `struct trp_root` variable and sets it to {~0}.
. Adds new nodes to the set using `foo_insert`. Any pointers
to existing nodes cannot be relied upon any more, so the caller
might retrieve them anew with `foo_pointer`.
. Can find a specific item in the set using `foo_search`.
. Can iterate over items in the set using `foo_first` and `foo_next`.
. Can remove an item from the set using `foo_remove`.
Example:
----
struct ex_node {
const char *s;
struct trp_node ex_link;
};
static struct trp_root ex_base = {~0};
obj_pool_gen(ex, struct ex_node, 4096);
trp_gen(static, ex_, struct ex_node, ex_link, ex, strcmp)
struct ex_node *item;
item = ex_pointer(ex_alloc(1));
item->s = "hello";
ex_insert(&ex_base, item);
item = ex_pointer(ex_alloc(1));
item->s = "goodbye";
ex_insert(&ex_base, item);
for (item = ex_first(&ex_base); item; item = ex_next(&ex_base, item))
printf("%s\n", item->s);
----
Functions
---------
trp_gen(attr, foo_, node_type, link_field, pool, cmp)::
Generate a type-specific treap implementation.
+
. The storage class for generated functions will be 'attr' (e.g., `static`).
. Generated function names are prefixed with 'foo_' (e.g., `treap_`).
. Treap nodes will be of type 'node_type' (e.g., `struct treap_node`).
This type must be a struct with at least one `struct trp_node` field
to point to its children.
. The field used to access child nodes will be 'link_field'.
. All treap nodes must lie in the 'pool' object pool.
. Treap nodes must be totally ordered by the 'cmp' relation, with the
following prototype:
+
int (*cmp)(node_type \*a, node_type \*b)
+
and returning a value less than, equal to, or greater than zero
according to the result of comparison.
node_type {asterisk}foo_insert(struct trp_root *treap, node_type \*node)::
Insert node into treap. If inserted multiple times,
a node will appear in the treap multiple times.
+
The return value is the address of the node within the treap,
which might differ from `node` if `pool_alloc` had to call
`realloc` to expand the pool.
void foo_remove(struct trp_root *treap, node_type \*node)::
Remove node from treap. Caller must ensure node is
present in treap before using this function.
node_type *foo_search(struct trp_root \*treap, node_type \*key)::
Search for a node that matches key. If no match is found,
result is NULL.
node_type *foo_nsearch(struct trp_root \*treap, node_type \*key)::
Like `foo_search`, but if if the key is missing return what
would be key's successor, were key in treap (NULL if no
successor).
node_type *foo_first(struct trp_root \*treap)::
Find the first item from the treap, in sorted order.
node_type *foo_next(struct trp_root \*treap, node_type \*node)::
Find the next item.