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non-macro array, use _locate in _insert

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Gregory Burd 2024-03-20 12:18:46 -04:00
parent 66b2dda55c
commit 448aa42e6c
3 changed files with 529 additions and 484 deletions
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8
.clang-format
View file

@ -99,10 +99,10 @@ IndentPPDirectives: None
Language: Cpp Language: Cpp
NamespaceIndentation: None NamespaceIndentation: None
PointerAlignment: Right PointerAlignment: Right
ContinuationIndentWidth: 2 ContinuationIndentWidth: 4
IndentWidth: 2 IndentWidth: 4
TabWidth: 2 TabWidth: 4
ColumnLimit: 80 ColumnLimit: 160
UseTab: Never UseTab: Never
SpaceAfterCStyleCast: false SpaceAfterCStyleCast: false
IncludeBlocks: Regroup IncludeBlocks: Regroup

5
examples/slm.c
View file

@ -4,7 +4,10 @@
#include <stdint.h> #include <stdint.h>
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
#include <time.h>
#include <unistd.h>
#define SKIPLIST_MAX_HEIGHT 12
#include "../include/sl.h" #include "../include/sl.h"
/* /*
@ -99,7 +102,7 @@ main()
rc = ENOMEM; rc = ENOMEM;
goto fail; goto fail;
} }
rc = api_skip_init_slex(list, 12, 4, __slm_key_compare); rc = api_skip_init_slex(list, 12, __slm_key_compare);
if (rc) if (rc)
return rc; return rc;

340
include/sl.h
View file

@ -35,44 +35,69 @@
/* /*
* This file defines a skiplist data structure. * This file defines a skiplist data structure.
* *
* In 1990 William Pugh published: * A skiplist is a way of storing sorted elements in such a way that they can be
* accessed, inserted and removed, all in O(log(n)) on average.
*
* Conceptually, a skiplist is arranged as follows:
*
* <head> ----------> [2] --------------------------------------------------> [9] ---------->
* <head> ----------> [2] ------------------------------------[7] ----------> [9] ---------->
* <head> ----------> [2] ----------> [4] ------------------> [7] ----------> [9] --> [10] ->
* <head> --> [1] --> [2] --> [3] --> [4] --> [5] --> [6] --> [7] --> [8] --> [9] --> [10] ->
*
* Each node contains at the very least a link to the next element in the list
* (corresponding to the lowest level in the above diagram), but it can randomly
* contain more links which skip further down the list (the towers in the above
* diagram). This allows for the algorithm to move down the list faster than
* having to visit every element.
*
* Conceptually, the skiplist can be thought of as a stack of linked lists. At
* the very bottom is the full linked list with every element, and each layer
* above corresponds to a linked list containing a random subset of the elements
* from the layer immediately below it. The probability distribution that
* determines this random subset can be customized, but typically a layer will
* contain half the nodes from the layer below.
*
* This implementation maintains a doubly-linked list at the bottom layer to
* support efficient iteration in either direction. There is also a guard
* node at the tail rather than simply pointing to NULL.
*
* <head> <-> [1] <-> [2] <-> [3] <-> [4] <-> [5] <-> [6] <-> [7] <-> <tail>
*
* Safety:
*
* The ordered skiplist relies on a well-behaved comparison
* function. Specifically, given some ordering function f(a, b), it must satisfy
* the following properties:
*
* 1) Be well defined: f(a, b) should always return the same value
* 2) Be anti-symmetric: f(a, b) == Greater if and only if f(b, a) == Less, and
* f(a, b) == Equal == f(b, a).
* 3) Be transitive: If f(a, b) == Greater and f(b, c) == Greater then f(a, c)
* == Greater.
*
* Failure to satisfy these properties can result in unexpected behavior at
* best, and at worst will cause a segfault, null deref, or some other bad
* behavior.
*
* References for this implementation include, but are not limited to:
*
* - Skiplists: a probabilistic alternative to balanced trees. * - Skiplists: a probabilistic alternative to balanced trees.
* https://www.cl.cam.ac.uk/teaching/2005/Algorithms/skiplists.pdf * https://www.cl.cam.ac.uk/teaching/2005/Algorithms/skiplists.pdf
* A Skiplist is an ordered data structure providing expected O(Log(n)) lookup, * 1990 William Pugh published:
* insertion, and deletion complexity.
*/ */
/*
* Private, internal API.
*/
/* NOTE:
* This array is a bit unusual, while values are 0-based the array is allocated
* with space for two more pointers which are used to store max size the array
* can grow to (`array[-2]`) and the length, or number of elements used in the
* array so far (`array[-1]`).
*/
#define ARRAY_ALLOC(var, type, size) \
do { \
(size) = (size == 0 ? 254 : size); \
(var) = (type **)calloc(sizeof(type *), size + 2); \
if ((var) != NULL) { \
*(var)++ = (void *)(uintptr_t)size; \
*(var)++ = (void *)(uintptr_t)0; \
} \
} while (0)
#define ARRAY_FREE(list) free((list)-2)
#define ARRAY_SIZE(list) (unsigned int)(uintptr_t)(list)[-2]
#define ARRAY_SET_SIZE(list, size) (list)[-2] = (void *)(uintptr_t)(size)
#define ARRAY_LENGTH(list) (unsigned int)(uintptr_t)(list)[-1]
#define ARRAY_SET_LENGTH(list, len) (list)[-1] = (void *)(uintptr_t)(len)
/* /*
* Skiplist declarations. * Skiplist declarations.
*/ */
#ifndef SKIPLIST_MAX_HEIGHT
#define SKIPLIST_MAX_HEIGHT 1
#endif
#define SKIP_HEAD(name, type) \ #define SKIP_HEAD(name, type) \
struct name { \ struct name { \
size_t level, length, max, fanout; \ size_t level, length, max; \
int (*cmp)(struct name *, struct type *, struct type *, void *); \ int (*cmp)(struct name *, struct type *, struct type *, void *); \
void *aux; \ void *aux; \
struct type *slh_head; \ struct type *slh_head; \
@ -81,7 +106,11 @@
#define SKIP_ENTRY(type) \ #define SKIP_ENTRY(type) \
struct { \ struct { \
struct type **sle_next; \ struct __sle { \
struct type **next; \
size_t cap; \
size_t len; \
} sle; \
struct type *sle_prev; \ struct type *sle_prev; \
} }
@ -90,7 +119,7 @@
*/ */
#define SKIP_FIRST(head) ((head)->slh_head) #define SKIP_FIRST(head) ((head)->slh_head)
#define SKIP_LAST(head) ((head)->slh_tail) #define SKIP_LAST(head) ((head)->slh_tail)
#define SKIP_NEXT(elm, field) ((elm)->field.sle_next[0]) #define SKIP_NEXT(elm, field) ((elm)->field.sle.next[0])
#define SKIP_PREV(elm, field) ((elm)->field.sle_prev) #define SKIP_PREV(elm, field) ((elm)->field.sle_prev)
#define SKIP_EMPTY(head) ((head)->length == 0) #define SKIP_EMPTY(head) ((head)->length == 0)
@ -112,12 +141,18 @@
#define SKIPLIST_DECL(decl, prefix, field, free_node_blk, update_node_blk) \ #define SKIPLIST_DECL(decl, prefix, field, free_node_blk, update_node_blk) \
\ \
struct __##decl##_path { \
size_t cap; \
size_t len; \
struct decl##_node **nodes; \
}; \
\
/* Skiplist node type */ \ /* Skiplist node type */ \
typedef struct decl##_node decl##_node_t; \ typedef struct decl##_node decl##_node_t; \
\ \
/* Skiplist type */ \ /* Skiplist type */ \
typedef struct decl { \ typedef struct decl { \
size_t level, length, max, fanout; \ size_t level, length, max; \
int (*cmp)(struct decl *, decl##_node_t *, decl##_node_t *, void *); \ int (*cmp)(struct decl *, decl##_node_t *, decl##_node_t *, void *); \
void *aux; \ void *aux; \
decl##_node_t *slh_head; \ decl##_node_t *slh_head; \
@ -146,15 +181,20 @@
return slist->cmp(slist, a, b, aux); \ return slist->cmp(slist, a, b, aux); \
} \ } \
\ \
/* -- __skip_toss_ */ \ /* -- __skip_toss_ \
static int __skip_toss_##decl(size_t max, size_t fanout) \ * A "coin toss" function that is critical to the proper operation of the \
* Skiplist. For example, when `max = 6` this function returns 0 with \
* probability 0.5, 1 with 0.25, 2 with 0.125, etc. until 6 with 0.5^7. \
*/ \
static int __skip_toss_##decl(size_t max) \
{ \ { \
size_t level = 0; \ size_t level = 0; \
while (level + 1 < max) { \ double probability = 0.5; \
if (rand() % fanout == 0) /* NOLINT(*-msc50-cpp) */ \ \
double random_value = (double)rand() / RAND_MAX; \
while (random_value < probability && level < max) { /* NOLINT(*-msc50-cpp) */ \
level++; \ level++; \
else \ probability *= 0.5; \
break; \
} \ } \
return level; \ return level; \
} \ } \
@ -163,27 +203,29 @@
int prefix##skip_alloc_node_##decl(decl##_t *slist, decl##_node_t **node) \ int prefix##skip_alloc_node_##decl(decl##_t *slist, decl##_node_t **node) \
{ \ { \
decl##_node_t *n; \ decl##_node_t *n; \
n = (decl##_node_t *)calloc(1, sizeof(decl##_node_t)); \ /* Calculate the size of the struct sle within decl##_node_t, multiply \
ARRAY_ALLOC(n->field.sle_next, struct decl##_node, slist->max); \ by array size. */ \
if (n && n->field.sle_next) { \ size_t sle_arr_sz = (sizeof(size_t) + offsetof(struct __sle, len)) * slist->max; \
ARRAY_SET_SIZE(n->field.sle_next, slist->max); \ n = (decl##_node_t *)calloc(1, sizeof(decl##_node_t) + sle_arr_sz); \
ARRAY_SET_LENGTH(n->field.sle_next, 0); \ if (n == NULL) \
return ENOMEM; \
n->field.sle.cap = slist->max; \
n->field.sle.len = 0; \
n->field.sle.next = (decl##_node_t **)((uintptr_t)n + sizeof(decl##_node_t)); \
*node = n; \ *node = n; \
return 0; \ return 0; \
} \
return ENOMEM; \
} \ } \
\ \
/* -- skip_init_ \ /* -- skip_init_ \
* max: 12, fanout: 4 are good defaults. \ * \
*/ \ */ \
int prefix##skip_init_##decl(decl##_t *slist, size_t max, size_t fanout, int (*cmp)(struct decl *, decl##_node_t *, decl##_node_t *, void *)) \ int prefix##skip_init_##decl(decl##_t *slist, int max, int (*cmp)(struct decl *, decl##_node_t *, decl##_node_t *, void *)) \
{ \ { \
int rc = 0; \ int rc = 0; \
size_t i; \
slist->level = 0; \ slist->level = 0; \
slist->length = 0; \ slist->length = 0; \
slist->max = max; \ slist->max = (size_t)(max < 0 ? -max : max); \
slist->fanout = fanout; \
slist->cmp = cmp; \ slist->cmp = cmp; \
rc = prefix##skip_alloc_node_##decl(slist, &slist->slh_head); \ rc = prefix##skip_alloc_node_##decl(slist, &slist->slh_head); \
if (rc) \ if (rc) \
@ -191,14 +233,20 @@
rc = prefix##skip_alloc_node_##decl(slist, &slist->slh_tail); \ rc = prefix##skip_alloc_node_##decl(slist, &slist->slh_tail); \
if (rc) \ if (rc) \
goto fail; \ goto fail; \
ARRAY_SET_LENGTH(slist->slh_head->field.sle_next, max); \ slist->slh_head->field.sle.len = slist->max; \
for (size_t __i = 0; __i < max; __i++) \ for (i = 0; i < slist->max; i++) \
slist->slh_head->field.sle_next[__i] = slist->slh_tail; \ slist->slh_head->field.sle.next[i] = slist->slh_tail; \
slist->slh_head->field.sle_prev = NULL; \ slist->slh_head->field.sle_prev = NULL; \
ARRAY_SET_LENGTH(slist->slh_tail->field.sle_next, max); \ slist->slh_tail->field.sle.len = slist->max; \
for (size_t __i = 0; __i < max; __i++) \ for (i = 0; i < slist->max; i++) \
slist->slh_tail->field.sle_next[__i] = NULL; \ slist->slh_tail->field.sle.next[i] = NULL; \
slist->slh_head->field.sle_prev = slist->slh_tail; \ slist->slh_head->field.sle_prev = slist->slh_tail; \
/* Testing aid: set `max` to a negative number to seed the PRNG in a \
predictable way and have reproducible numbers. */ \
if (max < 0) \
srand(-max); \
else \
srand(((unsigned int)time(NULL) ^ getpid())); \
fail:; \ fail:; \
return rc; \ return rc; \
} \ } \
@ -207,7 +255,6 @@
void prefix##skip_free_node_##decl(decl##_node_t *node) \ void prefix##skip_free_node_##decl(decl##_node_t *node) \
{ \ { \
free_node_blk; \ free_node_blk; \
ARRAY_FREE(node->field.sle_next); \
free(node); \ free(node); \
} \ } \
\ \
@ -226,7 +273,7 @@
/* -- skip_head_ */ \ /* -- skip_head_ */ \
decl##_node_t *prefix##skip_head_##decl(decl##_t *slist) \ decl##_node_t *prefix##skip_head_##decl(decl##_t *slist) \
{ \ { \
return slist->slh_head->field.sle_next[0]; \ return slist->slh_head->field.sle.next[0]; \
} \ } \
\ \
/* -- skip_tail_ */ \ /* -- skip_tail_ */ \
@ -235,92 +282,80 @@
return slist->slh_tail->field.sle_prev; \ return slist->slh_tail->field.sle_prev; \
} \ } \
\ \
/* -- skip_locate_ \ /* -- __skip_locate_ \
* Locates a node that matches another node returning the path to that \ * Locates a node that matches another node updating `path` and then \
* node and the match in path[0]. \ * returning the length of that path + 1 to the node and the matching \
* node in path[0], or NULL at path[0] where there wasn't a match. \
* sizeof(path) should be `slist->max + 1` \
*/ \ */ \
decl##_node_t **prefix##skip_locate_##decl(decl##_t *slist, decl##_node_t *n) \ static size_t __skip_locate_##decl(decl##_t *slist, decl##_node_t *n, decl##_node_t **path) \
{ \ { \
unsigned int i; \ unsigned int i; \
decl##_node_t **path; \ size_t len = 0; \
decl##_node_t *elm = slist->slh_head; \ decl##_node_t *elm = slist->slh_head; \
\ \
if (slist == NULL || n == NULL) \ if (slist == NULL || n == NULL) \
return NULL; \ return 0; \
\
i = slist->max + 1; \
ARRAY_ALLOC(path, decl##_node_t, i); \
ARRAY_SET_LENGTH(path, 1); \
i = slist->level; \
if (path == NULL) \
return NULL; \
\ \
/* Find the node that matches `node` or NULL. */ \ /* Find the node that matches `node` or NULL. */ \
i = slist->level; \
do { \ do { \
while (elm && __skip_key_compare_##decl(slist, elm->field.sle_next[i], n, slist->aux) < 0) \ while (elm && __skip_key_compare_##decl(slist, elm->field.sle.next[i], n, slist->aux) < 0) \
elm = elm->field.sle_next[i]; \ elm = elm->field.sle.next[i]; \
path[i + 1] = elm; \ path[i + 1] = elm; \
ARRAY_SET_LENGTH(path, ARRAY_LENGTH(path) + 1); \ len++; \
} while (i--); \ } while (i--); \
elm = elm->field.sle_next[0]; \ elm = elm->field.sle.next[0]; \
if (__skip_key_compare_##decl(slist, elm, n, slist->aux) == 0) { \ if (__skip_key_compare_##decl(slist, elm, n, slist->aux) == 0) { \
path[0] = elm; \ path[0] = elm; \
return path; \
} \ } \
ARRAY_FREE(path); \ return len; \
return NULL; \
} \ } \
\ \
/* -- __skip_insert_ */ \ /* -- __skip_insert_ */ \
static int __skip_insert_##decl(decl##_t *slist, decl##_node_t *n, int flags) \ static int __skip_insert_##decl(decl##_t *slist, decl##_node_t *n, int flags) \
{ \ { \
unsigned int i; \ static decl##_node_t apath[SKIPLIST_MAX_HEIGHT]; \
decl##_node_t *prev, *elm = slist->slh_head; \ size_t i, len, level; \
decl##_node_t **path; \ decl##_node_t *node, **path = (decl##_node_t **)&apath; \
\ \
if (n == NULL) \ if (slist == NULL || n == NULL) \
return ENOENT; \ return ENOENT; \
\ \
i = slist->level; \ /* Allocate a buffer */ \
ARRAY_ALLOC(path, decl##_node_t, slist->max); \ if (SKIPLIST_MAX_HEIGHT == 1) { \
path = malloc(sizeof(decl##_node_t *) * slist->max + 1); \
if (path == NULL) \ if (path == NULL) \
return ENOMEM; \ return ENOMEM; \
} \
\ \
/* Find the position in the list where this element belongs. */ \ len = __skip_locate_##decl(slist, n, path); \
do { \ node = path[0]; \
while (elm && __skip_key_compare_##decl(slist, elm->field.sle_next[i], n, slist->aux) < 0) \ if (len > 0) { \
elm = elm->field.sle_next[i]; \ if ((node != NULL) && (flags == 0)) { \
path[i] = elm; \ /* Don't insert, duplicate flag not set. */ \
ARRAY_SET_LENGTH(path, ARRAY_LENGTH(path) + 1); \
} while (i--); \
i = 0; \
prev = elm; \
elm = elm->field.sle_next[0]; \
if (__skip_key_compare_##decl(slist, elm, n, slist->aux) == 0) { \
if (flags == 0) { \
/* Don't overwrite, to do that use _REPLACE not _INSERT */ \
ARRAY_FREE(path); \
return -1; \ return -1; \
} \ } \
} \ level = __skip_toss_##decl(slist->max); \
size_t level = __skip_toss_##decl(slist->max, slist->fanout); \ n->field.sle.len = level + 1; \
ARRAY_SET_LENGTH(n->field.sle_next, level + 1); \
if (level > slist->level) { \
for (i = slist->level + 1; i <= level; i++) { \
path[i] = slist->slh_tail; \
} \
slist->level = level; \
} \
for (i = 0; i <= level; i++) { \ for (i = 0; i <= level; i++) { \
n->field.sle_next[i] = path[i]->field.sle_next[i]; \ if (i <= slist->level) { \
path[i]->field.sle_next[i] = n; \ n->field.sle.next[i] = path[i + 1]->field.sle.next[i]; \
path[i + 1]->field.sle.next[i] = n; \
} else { \
n->field.sle.next[i] = slist->slh_tail; \
slist->level++; \
} \ } \
n->field.sle_prev = prev; \ } \
if (n->field.sle_next[0] == slist->slh_tail) { \ n->field.sle_prev = path[1]; \
if (n->field.sle.next[0] == slist->slh_tail) { \
slist->slh_tail->field.sle_prev = n; \ slist->slh_tail->field.sle_prev = n; \
} \ } \
slist->length++; \ slist->length++; \
ARRAY_FREE(path); \ \
if (SKIPLIST_MAX_HEIGHT == 1) \
free(path); \
} \
return 0; \ return 0; \
} \ } \
\ \
@ -352,10 +387,10 @@
i = slist->level; \ i = slist->level; \
\ \
do { \ do { \
while (elm && __skip_key_compare_##decl(slist, elm->field.sle_next[i], n, slist->aux) < 0) \ while (elm && __skip_key_compare_##decl(slist, elm->field.sle.next[i], n, slist->aux) < 0) \
elm = elm->field.sle_next[i]; \ elm = elm->field.sle.next[i]; \
} while (i--); \ } while (i--); \
elm = elm->field.sle_next[0]; \ elm = elm->field.sle.next[0]; \
if (__skip_key_compare_##decl(slist, elm, n, slist->aux) == 0) { \ if (__skip_key_compare_##decl(slist, elm, n, slist->aux) == 0) { \
return elm; \ return elm; \
} \ } \
@ -377,11 +412,11 @@
i = slist->level; \ i = slist->level; \
\ \
do { \ do { \
while (elm && __skip_key_compare_##decl(slist, elm->field.sle_next[i], n, slist->aux) < 0) \ while (elm && __skip_key_compare_##decl(slist, elm->field.sle.next[i], n, slist->aux) < 0) \
elm = elm->field.sle_next[i]; \ elm = elm->field.sle.next[i]; \
} while (i--); \ } while (i--); \
do { \ do { \
elm = elm->field.sle_next[0]; \ elm = elm->field.sle.next[0]; \
cmp = __skip_key_compare_##decl(slist, elm, n, slist->aux); \ cmp = __skip_key_compare_##decl(slist, elm, n, slist->aux); \
} while (cmp < 0); \ } while (cmp < 0); \
return elm; \ return elm; \
@ -402,10 +437,10 @@
i = slist->level; \ i = slist->level; \
\ \
do { \ do { \
while (elm && __skip_key_compare_##decl(slist, elm->field.sle_next[i], n, slist->aux) < 0) \ while (elm && __skip_key_compare_##decl(slist, elm->field.sle.next[i], n, slist->aux) < 0) \
elm = elm->field.sle_next[i]; \ elm = elm->field.sle.next[i]; \
} while (i--); \ } while (i--); \
elm = elm->field.sle_next[0]; \ elm = elm->field.sle.next[0]; \
if (__skip_key_compare_##decl(slist, elm, n, slist->aux) == 0) { \ if (__skip_key_compare_##decl(slist, elm, n, slist->aux) == 0) { \
return elm; \ return elm; \
} else { \ } else { \
@ -441,33 +476,42 @@
/* -- skip_remove_ */ \ /* -- skip_remove_ */ \
int prefix##skip_remove_##decl(decl##_t *slist, decl##_node_t *n) \ int prefix##skip_remove_##decl(decl##_t *slist, decl##_node_t *n) \
{ \ { \
size_t i, s; \ static decl##_node_t apath[SKIPLIST_MAX_HEIGHT]; \
decl##_node_t **path, *node; \ size_t i, len, level; \
decl##_node_t *node, **path = (decl##_node_t **)&apath; \
\ \
if (slist == NULL || n == NULL) \ if (slist == NULL || n == NULL) \
return -1; \ return -1; \
if (slist->length == 0) \ if (slist->length == 0) \
return 0; \ return 0; \
\ \
path = prefix##skip_locate_##decl(slist, n); \ /* Allocate a buffer */ \
s = ARRAY_LENGTH(path); \ if (SKIPLIST_MAX_HEIGHT == 1) { \
path = malloc(sizeof(decl##_node_t *) * slist->max + 1); \
if (path == NULL) \
return ENOMEM; \
} \
\
len = __skip_locate_##decl(slist, n, path); \
node = path[0]; \ node = path[0]; \
if (s > 0) { \ if (node) { \
node->field.sle_next[0]->field.sle_prev = node->field.sle_prev; \ node->field.sle.next[0]->field.sle_prev = node->field.sle_prev; \
for (i = 1; i < s; i++) { \ for (i = 1; i <= len; i++) { \
if (path[i]->field.sle_next[i - 1] != node) \ if (path[i]->field.sle.next[i - 1] != node) \
break; \ break; \
path[i]->field.sle_next[i - 1] = node->field.sle_next[i - 1]; \ path[i]->field.sle.next[i - 1] = node->field.sle.next[i - 1]; \
if (path[i]->field.sle_next[i - 1] == slist->slh_tail) { \ if (path[i]->field.sle.next[i - 1] == slist->slh_tail) { \
size_t h = ARRAY_LENGTH(path[i]->field.sle_next); \ level = path[i]->field.sle.len; \
ARRAY_SET_LENGTH(path[i]->field.sle_next, h - 1); \ path[i]->field.sle.len = level - 1; \
} \ } \
} \ } \
ARRAY_FREE(path); \ if (SKIPLIST_MAX_HEIGHT == 1) \
free(path); \
free_node_blk; \ free_node_blk; \
\
/* Find all levels in the first element in the list that point \ /* Find all levels in the first element in the list that point \
at the tail and shrink the level. */ \ at the tail and shrink the level. */ \
while (slist->level > 0 && slist->slh_head->field.sle_next[slist->level] == slist->slh_tail) { \ while (slist->level > 0 && slist->slh_head->field.sle.next[slist->level] == slist->slh_tail) { \
slist->level--; \ slist->level--; \
} \ } \
slist->length--; \ slist->length--; \
@ -480,9 +524,9 @@
{ \ { \
if (slist == NULL || n == NULL) \ if (slist == NULL || n == NULL) \
return NULL; \ return NULL; \
if (n->field.sle_next[0] == slist->slh_tail) \ if (n->field.sle.next[0] == slist->slh_tail) \
return NULL; \ return NULL; \
return n->field.sle_next[0]; \ return n->field.sle.next[0]; \
} \ } \
\ \
/* -- skip_prev_node_ */ \ /* -- skip_prev_node_ */ \
@ -510,9 +554,7 @@
node = next; \ node = next; \
} while (node != NULL); \ } while (node != NULL); \
\ \
ARRAY_FREE(slist->slh_head->field.sle_next); \
free(slist->slh_head); \ free(slist->slh_head); \
ARRAY_FREE(slist->slh_tail->field.sle_next); \
free(slist->slh_tail); \ free(slist->slh_tail); \
return 0; \ return 0; \
} \ } \
@ -596,14 +638,14 @@
static void __skip_dot_node_##decl(FILE *os, decl##_t *slist, decl##_node_t *node, size_t nsg, skip_sprintf_node_##decl##_t fn) \ static void __skip_dot_node_##decl(FILE *os, decl##_t *slist, decl##_node_t *node, size_t nsg, skip_sprintf_node_##decl##_t fn) \
{ \ { \
char buf[2048]; \ char buf[2048]; \
size_t level, height = ARRAY_LENGTH(node->field.sle_next); \ size_t level, height = node->field.sle.len; \
decl##_node_t *next; \ decl##_node_t *next; \
\ \
fprintf(os, "\"node%zu %p\"", nsg, (void *)node); \ fprintf(os, "\"node%zu %p\"", nsg, (void *)node); \
fprintf(os, " [label = \""); \ fprintf(os, " [label = \""); \
level = height; \ level = height; \
while (level--) { \ while (level--) { \
fprintf(os, " { <w%zu> | <f%zu> %p } |", level, level, (void *)node->field.sle_next[level]); \ fprintf(os, " { <w%zu> | <f%zu> %p } |", level, level, (void *)node->field.sle.next[level]); \
} \ } \
if (fn) { \ if (fn) { \
fn(node, buf); \ fn(node, buf); \
@ -619,7 +661,7 @@
for (level = 0; level < height; level++) { \ for (level = 0; level < height; level++) { \
fprintf(os, "\"node%zu %p\"", nsg, (void *)node); \ fprintf(os, "\"node%zu %p\"", nsg, (void *)node); \
fprintf(os, ":f%zu -> ", level); \ fprintf(os, ":f%zu -> ", level); \
fprintf(os, "\"node%zu %p\"", nsg, (void *)node->field.sle_next[level]); \ fprintf(os, "\"node%zu %p\"", nsg, (void *)node->field.sle.next[level]); \
fprintf(os, ":w%zu [];\n", level); \ fprintf(os, ":w%zu [];\n", level); \
} \ } \
next = prefix##skip_next_node_##decl(slist, node); \ next = prefix##skip_next_node_##decl(slist, node); \
@ -680,13 +722,13 @@
if (SKIP_EMPTY(slist)) \ if (SKIP_EMPTY(slist)) \
fprintf(os, "Empty HeadNode"); \ fprintf(os, "Empty HeadNode"); \
else { \ else { \
level = ARRAY_LENGTH(head->field.sle_next) - 1; \ level = head->field.sle.len - 1; \
do { \ do { \
decl##_node_t *node = head->field.sle_next[level]; \ decl##_node_t *node = head->field.sle.next[level]; \
fprintf(os, "{ <f%zu> %p }", level, (void *)node); \ fprintf(os, "{ <f%zu> %p }", level, (void *)node); \
if (level && head->field.sle_next[level] != slist->slh_tail) \ if (level && head->field.sle.next[level] != slist->slh_tail) \
fprintf(os, " | "); \ fprintf(os, " | "); \
} while (level-- && head->field.sle_next[level] != slist->slh_tail); \ } while (level-- && head->field.sle.next[level] != slist->slh_tail); \
} \ } \
fprintf(os, "\"\n"); \ fprintf(os, "\"\n"); \
fprintf(os, "shape = \"record\"\n"); \ fprintf(os, "shape = \"record\"\n"); \
@ -694,11 +736,11 @@
\ \
/* Edges for head node */ \ /* Edges for head node */ \
decl##_node_t *node = slist->slh_head; \ decl##_node_t *node = slist->slh_head; \
for (level = 0; level < ARRAY_LENGTH(slist->slh_head->field.sle_next); level++) { \ for (level = 0; level < slist->slh_head->field.sle.len; level++) { \
if (node->field.sle_next[level] == slist->slh_tail) \ if (node->field.sle.next[level] == slist->slh_tail) \
break; \ break; \
fprintf(os, "\"HeadNode%zu\":f%zu -> ", nsg, level); \ fprintf(os, "\"HeadNode%zu\":f%zu -> ", nsg, level); \
fprintf(os, "\"node%zu %p\"", nsg, (void *)node->field.sle_next[level]); \ fprintf(os, "\"node%zu %p\"", nsg, (void *)node->field.sle.next[level]); \
fprintf(os, ":w%zu [];\n", level); \ fprintf(os, ":w%zu [];\n", level); \
} \ } \
fprintf(os, "\n"); \ fprintf(os, "\n"); \
@ -713,7 +755,7 @@
tail = slist->slh_tail; \ tail = slist->slh_tail; \
if (!SKIP_EMPTY(slist)) { \ if (!SKIP_EMPTY(slist)) { \
fprintf(os, "\"node%zu %p\" [label = \"", nsg, (void *)slist->slh_tail); \ fprintf(os, "\"node%zu %p\" [label = \"", nsg, (void *)slist->slh_tail); \
level = ARRAY_LENGTH(tail->field.sle_next) - 1; \ level = tail->field.sle.len - 1; \
do { \ do { \
fprintf(os, "<w%zu> %p", level, (void *)node->field.sle_prev); \ fprintf(os, "<w%zu> %p", level, (void *)node->field.sle_prev); \
if (level && node->field.sle_prev != slist->slh_head) \ if (level && node->field.sle_prev != slist->slh_head) \