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adding dot and integrity

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This commit is contained in:
Gregory Burd 2024-03-18 14:58:35 -04:00
parent 7a15b70530
commit f6de9cb321
2 changed files with 211 additions and 23 deletions
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39
examples/slm.c
View file

@ -1,7 +1,9 @@
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <stddef.h>
#include <stdint.h>
#include <errno.h>
#include <string.h>
#include "../include/sl.h"
/*
@ -11,16 +13,43 @@
* 'slex' - meaning: SkipList EXample
*/
/* Create a type of Skiplist that maps int -> int. */
/*
* To start, you must create a type node that will contain the
* fields you'd like to maintain in your Skiplist. In this case
* we map int -> int, but what you put here is up to you. You
* don't even need a "key", just a way to compare one node against
* another, logic you'll provide in SKIP_DECL as a block below.
*/
struct slex_node {
int key;
int value;
SKIP_ENTRY(slex_node) entries;
};
SKIP_HEAD(slex, slex_node);
/* Generate all the access functions for our type of Skiplist. */
SKIP_DECL(slex, api_, entries, {
/*
* Generate all the access functions for our type of Skiplist.
* The last argument to this macro is a block of code used to
* compare the nodes you defined above.
* This block can expect four arguments:
* - a reference to the Skiplist, `slist`
* - the two nodes to compare, `a` and `b`
* - and `aux`, which you can use to pass into this function
* any additional information required to compare objects.
* `aux` is passed from the value in the Skiplist, you can
* modify that value at any time to suit your needs.
*
* Your block should result in a return statement:
* a < b : return -1
* a == b : return 0
* a > b : return 1
*
* This result provides the ordering within the Skiplist. Sometimes
* your block of code will not be used when comparing nodes. This
* happens when `a` or `b` are references to the head or tail of the
* list or when `a == b`. In those cases the comparison function
* returns before using the code in your block, don't panic. :)
*/
SKIPLIST_DECL(slex, api_, entries, {
(void)aux;
if (a->key < b->key)
return -1;

195
include/sl.h
View file

@ -122,15 +122,10 @@ struct sl_trace {
} \
} while(0)
#define ARRAY_FREE(var) free((var)-2)
#define ARRAY_SIZE(list) (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) (list)[-1]
#define ARRAY_LENGTH(list) (unsigned int)(uintptr_t)((list)-1)
#define ARRAY_SET_LENGTH(list, len) (list)[-1] = (void *)(uintptr_t)(len)
#define ARRAY_FOREACH(var, list) \
for(unsigned int (var) = 0; (var) < (unsigned int)(uintptr_t)ARRAY_LENGTH(list); (var)++)
#define ARRAY_FORALL(var, list) \
for(unsigned int (var) = 0; (var) < (unsigned int)(uintptr_t)ARRAY_SIZE(list); (var)++)
/*
* Skiplist declarations.
@ -213,12 +208,12 @@ struct sl_trace {
SKIP_ALLOC_NODE(head, (head)->slh_head, type, field); \
SKIP_ALLOC_NODE(head, (head)->slh_tail, type, field); \
ARRAY_SET_LENGTH((head)->slh_head->field.sle_next, max); \
ARRAY_FORALL(__i, (head)->slh_head->field.sle_next) { \
for(size_t __i = 0; __i < ARRAY_SIZE((head)->slh_head->field.sle_next); __i++) { \
(head)->slh_head->field.sle_next[__i] = (head)->slh_tail; \
} \
(head)->slh_head->field.sle_prev = NULL; \
ARRAY_SET_LENGTH((head)->slh_tail->field.sle_next, max); \
ARRAY_FORALL(__i, (head)->slh_tail->field.sle_next) { \
for(size_t __i = 0; __i < ARRAY_SIZE((head)->slh_tail->field.sle_next); __i++) { \
(head)->slh_tail->field.sle_next[__i] = NULL; \
} \
(head)->slh_head->field.sle_prev = (head)->slh_tail; \
@ -234,12 +229,12 @@ struct sl_trace {
SKIP_ALLOC_NODE(head, (head)->slh_head, type, field); \
SKIP_ALLOC_NODE(head, (head)->slh_tail, type, field); \
ARRAY_SET_LENGTH((head)->slh_head->field.sle_next, (head)->max); \
ARRAY_FORALL(__i, (head)->slh_head->field.sle_next) { \
for(size_t __i = 0; __i < ARRAY_SIZE((head)->slh_head->field.sle_next); __i++) { \
(head)->slh_head->field.sle_next[__i] = (head)->slh_tail; \
} \
(head)->slh_head->field.sle_prev = NULL; \
ARRAY_SET_LENGTH((head)->slh_tail->field.sle_next, (head)->max); \
ARRAY_FORALL(__i, (head)->slh_tail->field.sle_next) { \
ARRAY_SET_LENGTH((head)->slh_tail->field.sle_next, (head)->max); \
for(size_t __i = 0; __i < ARRAY_SIZE((head)->slh_tail->field.sle_next); __i++) { \
(head)->slh_tail->field.sle_next[__i] = NULL; \
} \
(head)->slh_head->field.sle_prev = (head)->slh_tail; \
@ -261,14 +256,22 @@ struct sl_trace {
free((node)); \
} while (0)
#define SKIP_DECL(decl, prefix, field, key_cmp_logic) \
/* Skiplist type */ \
typedef struct decl decl##_t; \
#define SKIPLIST_DECL(decl, prefix, field, key_cmp_logic) \
\
/* Skiplist node type */ \
typedef struct decl##_node decl##_node_t; \
\
/* -- __skip_key_compare_decl \
/* Skiplist type */ \
typedef struct decl { \
size_t level, length, max, fanout; \
int (*cmp)(struct decl *, decl##_node_t *, decl##_node_t *, void *); \
void *aux; \
decl##_node_t *slh_head; \
decl##_node_t *slh_tail; \
TRACEBUF \
}decl##_t; \
\
/* -- __skip_key_compare_ \
* \
* This function takes four arguments: \
* - a reference to the Skiplist \
@ -289,7 +292,7 @@ struct sl_trace {
do { key_cmp_logic } while(0); \
} \
\
/* -- __skip_toss_decl */ \
/* -- __skip_toss_ */ \
static int __skip_toss_##decl(size_t max, size_t fanout) { \
size_t level = 0; \
while (level + 1 < max) { \
@ -301,7 +304,7 @@ struct sl_trace {
return level; \
} \
\
/* -- prefixskip_insert_decl */ \
/* -- skip_insert_ */ \
int prefix##skip_insert_##decl(decl##_t *slist, decl##_node_t *n) { \
if (n == NULL) \
return ENOMEM; \
@ -346,6 +349,162 @@ struct sl_trace {
slist->length++; \
ARRAY_FREE(path); \
return 0; \
} \
\
/* -- __skip_integrity_check_ */ \
static int __skip_integrity_check_##decl() { \
return 0; \
} \
\
/* A type for a function that writes into a char[2048] buffer \
* a description of the value within the node. */ \
typedef void (*skip_sprintf_node_##decl##_t)(decl##_node_t *, char *); \
\
/* -- __skip_dot_node_ \
* Writes out a fragment of a DOT file representing a node. \
*/ \
static void __skip_dot_node_##decl(FILE *os, decl##_t *slist, decl##_node_t *node, size_t suffix, skip_sprintf_node_##decl##_t fn) { \
fprintf(os, "\"node%zu%p\"", suffix, (void*)node); \
fprintf(os, " [label = \""); \
size_t level = ARRAY_LENGTH(node->field.sle_next); \
do { \
fprintf(os, " { <w%zu> | <f%zu> %p }", level, level, (void*)node->field.sle_next[level]); \
if (level != 0) fprintf(os, " | "); \
} while (level--); \
if (fn) { \
char buf[2048]; \
fn(node, buf); \
fprintf(os, " <f0> %s\"\n", buf); \
} else { \
fprintf(os, " <f0> ?\"\n"); \
} \
fprintf(os, "shape = \"record\"\n"); \
fprintf(os, "];\n"); \
\
/* Now edges */ \
level = 0; \
size_t size = ARRAY_LENGTH(node->field.sle_next); \
for (size_t level = 0; level <= size; level++) { \
fprintf(os, "\"node%zu%p\"", suffix, (void*)node); \
fprintf(os, ":f%zu -> SomeNode [style=solid];\n", level); \
} \
\
if (node->field.sle_next[0]) \
__skip_dot_node_##decl(os, slist, node->field.sle_next[0], suffix, fn); \
} \
\
/* -- __skip_dot_finish_ \
* Finalise the DOT file of the internal representation. \
*/ \
static void __skip_dot_finish_##decl(FILE *os, size_t nsg) { \
if (nsg > 0) { \
/* Link the nodes together with an invisible node. */ \
fprintf(os, "node0 [shape=record, label = \""); \
for (size_t i = 0; i < nsg; ++i) { \
fprintf(os, "<f%zu> | ", i); \
} \
fprintf(os, "\", style=invis, width=0.01];\n"); \
\
/* Now connect nodes with invisible edges */ \
for (size_t i = 0; i < nsg; ++i) { \
fprintf(os, "node0:f%zu -> HeadNode%zu [style=invis];\n", i, i);\
} \
nsg = 0; \
} \
fprintf(os, "}\n"); \
} \
\
/* -- skip_dot_start_ */ \
static int __skip_dot_start_##decl(FILE *os, decl##_t *slist, size_t nsg) { \
if (nsg == 0) { \
fprintf(os, "digraph Skiplist {\n"); \
fprintf(os, "label = \"Skiplist.\"\n"); \
fprintf(os, "graph [rankdir = \"LR\"];\n"); \
fprintf(os, "node [fontsize = \"12\" shape = \"ellipse\"];\n"); \
fprintf(os, "edge [];\n\n"); \
} \
fprintf(os, "subgraph cluster%zu {\n", nsg); \
fprintf(os, "style=dashed\n"); \
fprintf(os, "label=\"Skip list iteration %zu\"\n\n", nsg); \
fprintf(os, "\"HeadNode%zu\" [\n", nsg); \
fprintf(os, "label = \""); \
\
/* Write out the head node fields */ \
decl##_node_t *head = slist->slh_head; \
size_t level; \
if (SKIP_EMPTY(slist)) fprintf(os, "Empty HeadNode"); else { \
level = ARRAY_LENGTH(head->field.sle_next); \
do { \
decl##_node_t *node = head->field.sle_next[level]; \
fprintf(os, "{ <f%zu> %p }", level + 1, (void *)node); \
if (level != 0) fprintf(os, " | "); \
} while(level--); \
} \
fprintf(os, "\"\n"); \
fprintf(os, "shape = \"record\"\n"); \
fprintf(os, "];\n"); \
\
/* Edges for head node */ \
level = 0; \
do { \
fprintf(os, "\"HeadNode%zu\":f%zu -> ", nsg, level); \
/* Write logic to handle edge connections */ \
fprintf(os, "SomeNode [style=solid];\n"); \
} while(level++ < ARRAY_LENGTH(slist)); \
fprintf(os, "}\n\n"); \
\
/* Now all nodes via level 0, if non-empty */ \
decl##_node_t *node = slist->slh_head; \
if (ARRAY_LENGTH(node->field.sle_next)) \
__skip_dot_node_##decl(os, slist, node, nsg, NULL); \
fprintf(os, "\n"); \
\
/* The tail, sentinal node */ \
if (!SKIP_EMPTY(slist)) { \
fprintf(os,"\"node%zu0x0\" [label = \"", nsg); \
size_t level = slist->level; \
do { \
fprintf(os, "<w%zu> NULL", level); \
if (level != 0) \
fprintf(os, " | "); \
} while(level-- > 0); \
fprintf(os, "\" shape = \"record\"];\n"); \
} \
\
/* End: "subgraph cluster1 {" */ \
fprintf(os, "}\n\n"); \
nsg += 1; \
\
return 0; \
} \
\
/* -- skip_dot_ \
* Create a DOT file of the internal representation of the \
* Skiplist on the provided file descriptor (default: STDOUT). \
* \
* To view the output: \
* $ dot -Tps filename.dot -o outfile.ps \
* You can change the output format by varying the value after -T and \
* choosing an appropriate filename extension after -o. \
* See: https://graphviz.org/docs/outputs/ for the format options. \
* \
* https://en.wikipedia.org/wiki/DOT_(graph_description_language) \
*/ \
int prefix##skip_dot_##decl(FILE *os, decl##_t *slist) { \
size_t nsg = 0; \
if (__skip_integrity_check_##decl(slist) != 0) { \
perror("Skiplist failed integrity checks, impossible to diagram.");\
return -1; \
} \
if (os == NULL) \
os = stdout; \
if (!os) { \
perror("Failed to open output file, unable to write DOT file.");\
return -1; \
} \
__skip_dot_start_##decl(os, slist, nsg); \
__skip_dot_finish_##decl(os, nsg); \
return 0; \
} \
/* END */