src/commonlib/sort.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <commonlib/helpers.h>
   4 #include <commonlib/sort.h>
   5
   6 /* Implement a simple Bubble sort algorithm. Reduce the needed number of
   7    iterations by taking care of already sorted entries in the list. */
   8 void bubblesort(int *v, size_t num_entries, sort_order_t order)
   9 {
  10         size_t i, j;
  11         int swapped;
  12
  13         /* Make sure there are at least two entries to sort. */
  14         if (num_entries < 2)
  15                 return;
  16
  17         for (j = 0; j < num_entries - 1; j++) {
  18                 swapped = 0;
  19                 for (i = 0; i < num_entries - j - 1; i++) {
  20                         switch (order) {
  21                         case NUM_ASCENDING:
  22                                 if (v[i] > v[i + 1]) {
  23                                         SWAP(v[i], v[i + 1]);
  24                                         swapped = 1;
  25                                 }
  26                                 break;
  27                         case NUM_DESCENDING:
  28                                 if (v[i] < v[i + 1]) {
  29                                         SWAP(v[i], v[i + 1]);
  30                                         swapped = 1;
  31                                 }
  32                                 break;
  33                         default:
  34                                 return;
  35                         }
  36                 }
  37                 if (!swapped)
  38                         break;
  39         }
  40 }