Generate DOT Graph Description Language Based on a Tree Data Structure

generate_dots.c

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>
#include <dllist.h>

#define MAX_CHILDREN 32

typedef struct node {
  int val;
  char id;
  struct node *parent;
  struct node *children[MAX_CHILDREN];
} node;

typedef struct tree {
  int size;
  char gid;
  struct node *root;
} tree;

node *new_node(tree *t, node *parent, int val);

tree *new_tree();

void gen_graph(tree *t, char *name);

int main(int argc, char **argv)
{
  int i;
  tree *t;
  node *tmp;

  t = new_tree();

  srand48(time(0));

  t->root->val = lrand48() % 10;

  tmp = new_node(t, t->root, lrand48() % 10);

  new_node(t, tmp, lrand48() % 10);
  new_node(t, tmp, lrand48() % 10);

  tmp = new_node(t, t->root, lrand48() % 10);

  new_node(t, tmp, lrand48() % 10);
  new_node(t, tmp, lrand48() % 10);

  gen_graph(t, "muh_graph");

  return 0;
}

node *new_node(tree *t, node *parent, int val)
{
  int i;
  node *n;

  n = (node *) malloc(sizeof(node));

  n->parent = parent;
  n->val = val;
  n->id = (t->gid)++;

  for (i = 0; i < MAX_CHILDREN; i++) {
    n->children[i] = NULL;
  }

  if (parent != NULL) {
    for (i = 0; i < MAX_CHILDREN; i++) {
      if (parent->children[i] == NULL) {
        parent->children[i] = n;
        break;
      }

      if (i == MAX_CHILDREN - 1) {
        free(n);
        return NULL;
      }
    }
  }

  (t->size)++;

  return n;
}

tree *new_tree()
{
  tree *t;

  t = (tree *) malloc(sizeof(tree));
  t->gid = 'a';
  t->size += 1;
  t->root = new_node(t, NULL, 0);

  return t;
}

void gen_graph(tree *t, char *name)
{
  int i;
  Dllist q;
  node *n;

  printf("graph %s {\n", name);

  q = new_dllist();

  dll_append(q, new_jval_v(t->root));

  while (!dll_empty(q)) {
    n = jval_v(dll_first(q)->val);
    dll_delete_node(dll_first(q));

    printf("%c [label=\"%d\"];\n", n->id, n->val);

    if (n->children[0] != NULL) {

      /* Print route to children. */

     for (i = 0; i < MAX_CHILDREN; i++) {
        if (n->children[i] != NULL) {
          printf("%c -- %c;\n", n->id, n->children[i]->id);
        }
      }

      for (i = 0; i < MAX_CHILDREN; i++) {
        if (n->children[i] != NULL) {
          dll_append(q, new_jval_v(n->children[i]));
        }
      }
    }
  }

  printf("}");

  free_dllist(q);
}