array-omap: New module.

* lib/gl_array_omap.h: New file.
* lib/gl_array_omap.c: New file.
* modules/array-omap: New file.

1 files changed, 392 insertions, 0 deletions

diff --git a/lib/gl_array_omap.c b/lib/gl_array_omap.c
new file mode 100644
index 0000000000..d643fbac14
--- /dev/null
+++ b/lib/gl_array_omap.c
@@ -0,0 +1,392 @@
+/* Ordered map data type implemented by an array.
+   Copyright (C) 2006-2007, 2009-2018 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2018.
+
+   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 <https://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include "gl_array_omap.h"
+
+#include <stdlib.h>
+
+/* Checked size_t computations.  */
+#include "xsize.h"
+
+/* -------------------------- gl_omap_t Data Type -------------------------- */
+
+struct pair
+{
+  const void *key;
+  const void *value;
+};
+
+/* Concrete gl_omap_impl type, valid for this file only.  */
+struct gl_omap_impl
+{
+  struct gl_omap_impl_base base;
+  /* An array of ALLOCATED pairs, of which the first COUNT are used.
+     0 <= COUNT <= ALLOCATED.  */
+  struct pair *pairs;
+  size_t count;
+  size_t allocated;
+};
+
+static gl_omap_t
+gl_array_nx_create_empty (gl_omap_implementation_t implementation,
+                          gl_mapkey_compar_fn compar_fn,
+                          gl_mapkey_dispose_fn kdispose_fn,
+                          gl_mapvalue_dispose_fn vdispose_fn)
+{
+  struct gl_omap_impl *map =
+    (struct gl_omap_impl *) malloc (sizeof (struct gl_omap_impl));
+
+  if (map == NULL)
+    return NULL;
+
+  map->base.vtable = implementation;
+  map->base.compar_fn = compar_fn;
+  map->base.kdispose_fn = kdispose_fn;
+  map->base.vdispose_fn = vdispose_fn;
+  map->pairs = NULL;
+  map->count = 0;
+  map->allocated = 0;
+
+  return map;
+}
+
+static size_t
+gl_array_size (gl_omap_t map)
+{
+  return map->count;
+}
+
+static size_t
+gl_array_indexof (gl_omap_t map, const void *key)
+{
+  size_t count = map->count;
+
+  if (count > 0)
+    {
+      gl_mapkey_compar_fn compar = map->base.compar_fn;
+      size_t low = 0;
+      size_t high = count;
+
+      /* At each loop iteration, low < high; for indices < low the values
+         are smaller than KEY; for indices >= high the values are greater
+         than KEY.  So, if the key occurs in the map, it is at
+         low <= position < high.  */
+      do
+        {
+          size_t mid = low + (high - low) / 2; /* low <= mid < high */
+          int cmp = (compar != NULL
+                     ? compar (map->pairs[mid].key, key)
+                     : (map->pairs[mid].key > key ? 1 :
+                        map->pairs[mid].key < key ? -1 : 0));
+
+          if (cmp < 0)
+            low = mid + 1;
+          else if (cmp > 0)
+            high = mid;
+          else /* cmp == 0 */
+            /* We have a key equal to KEY at index MID.  */
+            return mid;
+        }
+      while (low < high);
+    }
+  return (size_t)(-1);
+}
+
+static bool
+gl_array_search (gl_omap_t map, const void *key, const void **valuep)
+{
+  size_t index = gl_array_indexof (map, key);
+  if (index != (size_t)(-1))
+    {
+      *valuep = map->pairs[index].value;
+      return true;
+    }
+  else
+    return false;
+}
+
+static bool
+gl_array_search_atleast (gl_omap_t map,
+                         gl_mapkey_threshold_fn threshold_fn,
+                         const void *threshold,
+                         const void **keyp, const void **valuep)
+{
+  size_t count = map->count;
+
+  if (count > 0)
+    {
+      size_t low = 0;
+      size_t high = count;
+
+      /* At each loop iteration, low < high; for indices < low the values are
+         smaller than THRESHOLD; for indices >= high the values are nonexistent.
+         So, if a key >= THRESHOLD occurs in the map, it is at
+         low <= position < high.  */
+      do
+        {
+          size_t mid = low + (high - low) / 2; /* low <= mid < high */
+
+          if (! threshold_fn (map->pairs[mid].key, threshold))
+            low = mid + 1;
+          else
+            {
+              /* We have a key >= THRESHOLD at index MID.  But we need the
+                 minimal such index.  */
+              high = mid;
+              /* At each loop iteration, low <= high and
+                   compar (map->pairs[high].key, value) >= 0,
+                 and we know that the first occurrence of the key is at
+                 low <= position <= high.  */
+              while (low < high)
+                {
+                  size_t mid2 = low + (high - low) / 2; /* low <= mid2 < high */
+
+                  if (! threshold_fn (map->pairs[mid2].key, threshold))
+                    low = mid2 + 1;
+                  else
+                    high = mid2;
+                }
+              *keyp = map->pairs[low].key;
+              *valuep = map->pairs[low].value;
+              return true;
+            }
+        }
+      while (low < high);
+    }
+  return false;
+}
+
+/* Ensure that map->allocated > map->count.
+   Return 0 upon success, -1 upon out-of-memory.  */
+static int
+grow (gl_omap_t map)
+{
+  size_t new_allocated;
+  size_t memory_size;
+  struct pair *memory;
+
+  new_allocated = xtimes (map->allocated, 2);
+  new_allocated = xsum (new_allocated, 1);
+  memory_size = xtimes (new_allocated, sizeof (struct pair));
+  if (size_overflow_p (memory_size))
+    /* Overflow, would lead to out of memory.  */
+    return -1;
+  memory = (struct pair *) realloc (map->pairs, memory_size);
+  if (memory == NULL)
+    /* Out of memory.  */
+    return -1;
+  map->pairs = memory;
+  map->allocated = new_allocated;
+  return 0;
+}
+
+/* Add the given pair (KEY, VALUE) at the given position,
+   0 <= position <= gl_omap_size (map).
+   Return 1 upon success, -1 upon out-of-memory.  */
+static int
+gl_array_nx_add_at (gl_omap_t map, size_t position,
+                    const void *key, const void *value)
+{
+  size_t count = map->count;
+  struct pair *pairs;
+  size_t i;
+
+  if (count == map->allocated)
+    if (grow (map) < 0)
+      return -1;
+  pairs = map->pairs;
+  for (i = count; i > position; i--)
+    pairs[i] = pairs[i - 1];
+  pairs[position].key = key;
+  pairs[position].value = value;
+  map->count = count + 1;
+  return 1;
+}
+
+/* Remove the pair at the given position,
+   0 <= position < gl_omap_size (map).  */
+static void
+gl_array_remove_at (gl_omap_t map, size_t position)
+{
+  size_t count = map->count;
+  struct pair *pairs;
+  size_t i;
+
+  pairs = map->pairs;
+  if (map->base.vdispose_fn != NULL)
+    map->base.vdispose_fn (pairs[position].value);
+  if (map->base.kdispose_fn != NULL)
+    map->base.kdispose_fn (pairs[position].key);
+  for (i = position + 1; i < count; i++)
+    pairs[i - 1] = pairs[i];
+  map->count = count - 1;
+}
+
+static int
+gl_array_nx_getput (gl_omap_t map, const void *key, const void *value,
+                    const void **oldvaluep)
+{
+  size_t count = map->count;
+  size_t low = 0;
+
+  if (count > 0)
+    {
+      gl_mapkey_compar_fn compar = map->base.compar_fn;
+      size_t high = count;
+
+      /* At each loop iteration, low < high; for indices < low the keys
+         are smaller than KEY; for indices >= high the keys are greater
+         than KEY.  So, if the key occurs in the map, it is at
+         low <= position < high.  */
+      do
+        {
+          size_t mid = low + (high - low) / 2; /* low <= mid < high */
+          int cmp = (compar != NULL
+                     ? compar (map->pairs[mid].key, key)
+                     : (map->pairs[mid].key > key ? 1 :
+                        map->pairs[mid].key < key ? -1 : 0));
+
+          if (cmp < 0)
+            low = mid + 1;
+          else if (cmp > 0)
+            high = mid;
+          else /* cmp == 0 */
+            {
+              *oldvaluep = map->pairs[mid].value;
+              map->pairs[mid].value = value;
+              return false;
+            }
+        }
+      while (low < high);
+    }
+  return gl_array_nx_add_at (map, low, key, value);
+}
+
+static bool
+gl_array_getremove (gl_omap_t map, const void *key, const void **oldvaluep)
+{
+  size_t index = gl_array_indexof (map, key);
+  if (index != (size_t)(-1))
+    {
+      *oldvaluep = map->pairs[index].value;
+      gl_array_remove_at (map, index);
+      return true;
+    }
+  else
+    return false;
+}
+
+static void
+gl_array_free (gl_omap_t map)
+{
+  if (map->pairs != NULL)
+    {
+      if (map->base.kdispose_fn != NULL || map->base.vdispose_fn != NULL)
+        {
+          size_t count = map->count;
+
+          if (count > 0)
+            {
+              gl_mapkey_dispose_fn kdispose = map->base.kdispose_fn;
+              gl_mapvalue_dispose_fn vdispose = map->base.vdispose_fn;
+              struct pair *pairs = map->pairs;
+
+              do
+                {
+                  if (vdispose)
+                    vdispose (pairs->value);
+                  if (kdispose)
+                    kdispose (pairs->key);
+                  pairs++;
+                }
+              while (--count > 0);
+            }
+        }
+      free (map->pairs);
+    }
+  free (map);
+}
+
+/* ---------------------- gl_omap_iterator_t Data Type ---------------------- */
+
+static gl_omap_iterator_t
+gl_array_iterator (gl_omap_t map)
+{
+  gl_omap_iterator_t result;
+
+  result.vtable = map->base.vtable;
+  result.map = map;
+  result.count = map->count;
+  result.p = map->pairs + 0;
+  result.q = map->pairs + map->count;
+#if defined GCC_LINT || defined lint
+  result.i = 0;
+  result.j = 0;
+#endif
+
+  return result;
+}
+
+static bool
+gl_array_iterator_next (gl_omap_iterator_t *iterator,
+                        const void **keyp, const void **valuep)
+{
+  gl_omap_t map = iterator->map;
+  if (iterator->count != map->count)
+    {
+      if (iterator->count != map->count + 1)
+        /* Concurrent modifications were done on the map.  */
+        abort ();
+      /* The last returned pair was removed.  */
+      iterator->count--;
+      iterator->p = (struct pair *) iterator->p - 1;
+      iterator->q = (struct pair *) iterator->q - 1;
+    }
+  if (iterator->p < iterator->q)
+    {
+      struct pair *p = (struct pair *) iterator->p;
+      *keyp = p->key;
+      *valuep = p->value;
+      iterator->p = p + 1;
+      return true;
+    }
+  else
+    return false;
+}
+
+static void
+gl_array_iterator_free (gl_omap_iterator_t *iterator)
+{
+}
+
+
+const struct gl_omap_implementation gl_array_omap_implementation =
+  {
+    gl_array_nx_create_empty,
+    gl_array_size,
+    gl_array_search,
+    gl_array_search_atleast,
+    gl_array_nx_getput,
+    gl_array_getremove,
+    gl_array_free,
+    gl_array_iterator,
+    gl_array_iterator_next,
+    gl_array_iterator_free
+  };