Rework xbt_dynar_three_way_partition.

[simgrid.git] / src / xbt / dynar.c

diff --git a/src/xbt/dynar.c b/src/xbt/dynar.c
index 6bf067c..2b6a287 100644 (file)
--- a/src/xbt/dynar.c
+++ b/src/xbt/dynar.c
@@ -238,6 +238,28 @@ XBT_INLINE void xbt_dynar_reset(xbt_dynar_t const dynar)
   _dynar_unlock(dynar);
 }
 
+/** @brief Merge dynar d2 into d1
+ *
+ * \param d1 dynar to keep
+ * \param d2 dynar to merge into d1. This dynar is free at end.
+ */
+void xbt_dynar_merge(xbt_dynar_t *d1, xbt_dynar_t *d2)
+{
+  if((*d1)->elmsize != (*d2)->elmsize)
+    xbt_die("Element size must are not equal");
+
+  const unsigned long elmsize = (*d1)->elmsize;
+
+  void *ptr = _xbt_dynar_elm((*d2), 0);
+  _xbt_dynar_resize(*d1, (*d1)->size + (*d2)->size);
+  void *elm = _xbt_dynar_elm((*d1), (*d1)->used);
+
+  memcpy(elm, ptr, ((*d2)->size)*elmsize);
+  (*d1)->used += (*d2)->used;
+  (*d2)->used = 0;
+  xbt_dynar_free(d2);
+}
+
 /**
  * \brief Shrink the dynar by removing empty slots at the end of the internal array
  * \param dynar a dynar
@@ -698,6 +720,53 @@ XBT_INLINE void xbt_dynar_sort(xbt_dynar_t dynar,
   _dynar_unlock(dynar);
 }
 
+/** @brief Sorts a dynar according to their color assuming elements can have only three colors.
+ * Since there are only three colors, it is linear and much faster than a classical sort.
+ * See for example http://en.wikipedia.org/wiki/Dutch_national_flag_problem
+ *
+ * \param dynar the dynar to sort
+ * \param color the color function of type (int (compar_fn*) (void*) (void*)). The return value of color is assumed to be 0, 1, or 2.
+ *
+ * At the end of the call, elements with color 0 are at the beginning of the dynar, elements with color 2 are at the end and elements with color 1 are in the middle.
+ *
+ * Remark: if the elements stored in the dynar are structures, the color
+ * function has to retrieve the field to sort first.
+ */
+XBT_PUBLIC(void) xbt_dynar_three_way_partition(xbt_dynar_t const dynar,
+                                               int_f_pvoid_t color)
+{
+  _dynar_lock(dynar);
+  unsigned long int i;
+  unsigned long int p = -1;
+  unsigned long int q = dynar->used;
+  const unsigned long elmsize = dynar->elmsize;
+  void *tmp = xbt_malloc(elmsize);
+  void *elm;
+
+  for (i = 0; i < q;) {
+    void *elmi = _xbt_dynar_elm(dynar, i);
+    int colori = color(elmi);
+
+    if (colori == 1) {
+      ++i;
+    } else {
+      if (colori == 0) {
+        elm = _xbt_dynar_elm(dynar, ++p);
+        ++i;
+      } else {                  /* colori == 2 */
+        elm = _xbt_dynar_elm(dynar, --q);
+      }
+      if (elm != elmi) {
+        memcpy(tmp,  elm,  elmsize);
+        memcpy(elm,  elmi, elmsize);
+        memcpy(elmi, tmp,  elmsize);
+      }
+    }
+  }
+  _dynar_unlock(dynar);
+  xbt_free(tmp);
+}
+
 /** @brief Transform a dynar into a NULL terminated array
  *
  * \param dynar the dynar to transform
@@ -762,8 +831,7 @@ XBT_INLINE int xbt_dynar_compare(xbt_dynar_t d1, xbt_dynar_t d2,
 #define NB_ELEM 5000
 
 XBT_TEST_SUITE("dynar", "Dynar data container");
-XBT_LOG_EXTERNAL_CATEGORY(xbt_dyn);
-XBT_LOG_DEFAULT_CATEGORY(xbt_dyn);
+XBT_LOG_EXTERNAL_DEFAULT_CATEGORY(xbt_dyn);
 
 XBT_TEST_UNIT("int", test_dynar_int, "Dynars of integers")
 {