aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/tools/m4/lib/gl_anytree_oset.h
blob: e1f90a99a220fd2b6cf38ca043a4e397a3ace59d (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
/* Ordered set data type implemented by a binary tree.
   Copyright (C) 2006-2007, 2009-2013 Free Software Foundation, Inc.
   Written by Bruno Haible <bruno@clisp.org>, 2006.

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

/* Common code of gl_avltree_oset.c and gl_rbtree_oset.c.  */

/* An item on the stack used for iterating across the elements.  */
typedef struct
{
  gl_oset_node_t node;
  bool rightp;
} iterstack_item_t;

/* A stack used for iterating across the elements.  */
typedef iterstack_item_t iterstack_t[MAXHEIGHT];

static gl_oset_t
gl_tree_nx_create_empty (gl_oset_implementation_t implementation,
                         gl_setelement_compar_fn compar_fn,
                         gl_setelement_dispose_fn dispose_fn)
{
  struct gl_oset_impl *set =
    (struct gl_oset_impl *) malloc (sizeof (struct gl_oset_impl));

  if (set == NULL)
    return NULL;

  set->base.vtable = implementation;
  set->base.compar_fn = compar_fn;
  set->base.dispose_fn = dispose_fn;
  set->root = NULL;
  set->count = 0;

  return set;
}

static size_t
gl_tree_size (gl_oset_t set)
{
  return set->count;
}

static bool
gl_tree_search (gl_oset_t set, const void *elt)
{
  gl_setelement_compar_fn compar = set->base.compar_fn;
  gl_oset_node_t node;

  for (node = set->root; node != NULL; )
    {
      int cmp = (compar != NULL
                 ? compar (node->value, elt)
                 : (node->value > elt ? 1 :
                    node->value < elt ? -1 : 0));

      if (cmp < 0)
        node = node->right;
      else if (cmp > 0)
        node = node->left;
      else /* cmp == 0 */
        /* We have an element equal to ELT.  */
        return true;
    }
  return false;
}

static bool
gl_tree_search_atleast (gl_oset_t set,
                        gl_setelement_threshold_fn threshold_fn,
                        const void *threshold,
                        const void **eltp)
{
  gl_oset_node_t node;

  for (node = set->root; node != NULL; )
    {
      if (! threshold_fn (node->value, threshold))
        node = node->right;
      else
        {
          /* We have an element >= VALUE.  But we need the leftmost such
             element.  */
          gl_oset_node_t found = node;
          node = node->left;
          for (; node != NULL; )
            {
              if (! threshold_fn (node->value, threshold))
                node = node->right;
              else
                {
                  found = node;
                  node = node->left;
                }
            }
          *eltp = found->value;
          return true;
        }
    }
  return false;
}

static gl_oset_node_t
gl_tree_search_node (gl_oset_t set, const void *elt)
{
  gl_setelement_compar_fn compar = set->base.compar_fn;
  gl_oset_node_t node;

  for (node = set->root; node != NULL; )
    {
      int cmp = (compar != NULL
                 ? compar (node->value, elt)
                 : (node->value > elt ? 1 :
                    node->value < elt ? -1 : 0));

      if (cmp < 0)
        node = node->right;
      else if (cmp > 0)
        node = node->left;
      else /* cmp == 0 */
        /* We have an element equal to ELT.  */
        return node;
    }
  return NULL;
}

static int
gl_tree_nx_add (gl_oset_t set, const void *elt)
{
  gl_setelement_compar_fn compar;
  gl_oset_node_t node = set->root;

  if (node == NULL)
    {
      if (gl_tree_nx_add_first (set, elt) == NULL)
        return -1;
      return true;
    }

  compar = set->base.compar_fn;

  for (;;)
    {
      int cmp = (compar != NULL
                 ? compar (node->value, elt)
                 : (node->value > elt ? 1 :
                    node->value < elt ? -1 : 0));

      if (cmp < 0)
        {
          if (node->right == NULL)
            {
              if (gl_tree_nx_add_after (set, node, elt) == NULL)
                return -1;
              return true;
            }
          node = node->right;
        }
      else if (cmp > 0)
        {
          if (node->left == NULL)
            {
              if (gl_tree_nx_add_before (set, node, elt) == NULL)
                return -1;
              return true;
            }
          node = node->left;
        }
      else /* cmp == 0 */
        return false;
    }
}

static bool
gl_tree_remove (gl_oset_t set, const void *elt)
{
  gl_oset_node_t node = gl_tree_search_node (set, elt);

  if (node != NULL)
    return gl_tree_remove_node (set, node);
  else
    return false;
}

static void
gl_tree_oset_free (gl_oset_t set)
{
  /* Iterate across all elements in post-order.  */
  gl_oset_node_t node = set->root;
  iterstack_t stack;
  iterstack_item_t *stack_ptr = &stack[0];

  for (;;)
    {
      /* Descend on left branch.  */
      for (;;)
        {
          if (node == NULL)
            break;
          stack_ptr->node = node;
          stack_ptr->rightp = false;
          node = node->left;
          stack_ptr++;
        }
      /* Climb up again.  */
      for (;;)
        {
          if (stack_ptr == &stack[0])
            goto done_iterate;
          stack_ptr--;
          node = stack_ptr->node;
          if (!stack_ptr->rightp)
            break;
          /* Free the current node.  */
          if (set->base.dispose_fn != NULL)
            set->base.dispose_fn (node->value);
          free (node);
        }
      /* Descend on right branch.  */
      stack_ptr->rightp = true;
      node = node->right;
      stack_ptr++;
    }
 done_iterate:
  free (set);
}

/* --------------------- gl_oset_iterator_t Data Type --------------------- */

static gl_oset_iterator_t
gl_tree_iterator (gl_oset_t set)
{
  gl_oset_iterator_t result;
  gl_oset_node_t node;

  result.vtable = set->base.vtable;
  result.set = set;
  /* Start node is the leftmost node.  */
  node = set->root;
  if (node != NULL)
    while (node->left != NULL)
      node = node->left;
  result.p = node;
  /* End point is past the rightmost node.  */
  result.q = NULL;
#ifdef lint
  result.i = 0;
  result.j = 0;
  result.count = 0;
#endif

  return result;
}

static bool
gl_tree_iterator_next (gl_oset_iterator_t *iterator, const void **eltp)
{
  if (iterator->p != iterator->q)
    {
      gl_oset_node_t node = (gl_oset_node_t) iterator->p;
      *eltp = node->value;
      /* Advance to the next node.  */
      if (node->right != NULL)
        {
          node = node->right;
          while (node->left != NULL)
            node = node->left;
        }
      else
        {
          while (node->parent != NULL && node->parent->right == node)
            node = node->parent;
          node = node->parent;
        }
      iterator->p = node;
      return true;
    }
  else
    return false;
}

static void
gl_tree_iterator_free (gl_oset_iterator_t *iterator)
{
}