bubble-sort.c

   1 /*
   2  * bubble-sort: there's no reason to this for anything.
   3  *
   4  * Luiz Fernando N. Capitulino <lcapitulino@mandriva.com.br>
   5  */
   6 #include <stdio.h>
   7 #include <string.h>
   8 #include <stdlib.h>
   9
  10 int compare(const void *key1, const void *key2)
  11 {
  12         if (*((const long *) key1) > *((const long *) key2))
  13                 return 1;
  14         else if (*((const long *) key1) < *((const long *) key2))
  15                 return -1;
  16         else
  17                 return 0;
  18 }
  19
  20 int bubble_sort(void *data, int size, int esize,
  21                 int (*compare) (const void *key1, const void *key2))
  22 {
  23         void *tmp;
  24         char *a = data;
  25
  26         tmp = (char *) malloc(esize);
  27         if (!tmp)
  28                 return -1;
  29
  30         for (;;) {
  31                 int i, has_swapped = 0;
  32
  33                 for (i = 0; i < size-1; i++) {
  34                         if (compare(&a[i * esize], &a[(i + 1) * esize]) > 0) {
  35                                 memcpy(tmp, &a[i * esize], esize);
  36                                 memcpy(&a[i * esize], &a[(i + 1) * esize],
  37                                        esize);
  38                                 memcpy(&a[(i + 1) * esize], tmp, esize);
  39                                 has_swapped = 1;
  40                         }
  41                 }
  42
  43                 if (!has_swapped)
  44                         break;
  45         }
  46
  47         free(tmp);
  48         return 0;
  49 }
  50
  51 int main(int argc, char *argv[])
  52 {
  53         int ret;
  54         long *nums;
  55         size_t len;
  56         unsigned int i;
  57
  58         if (argc == 1) {
  59                 printf("Usage: bubble-sort <num1> <num2> ... <numN>\n");
  60                 exit(1);
  61         }
  62
  63         len = argc - 1;
  64         nums = calloc(len, sizeof(long));
  65         if (!nums) {
  66                 perror("calloc()");
  67                 exit(1);
  68         }
  69
  70         for (i = 0; i < len; i++) {
  71                 nums[i] = strtol(argv[i + 1], (char **)NULL, 10);
  72                 printf("%ld ", nums[i]);
  73         }
  74         printf("\n");
  75
  76         ret = bubble_sort((void *) nums, len, sizeof(long), compare);
  77         if (ret) {
  78                 perror("bubble_sort()");
  79                 exit(1);
  80         }
  81
  82         for (i = 0; i < len; i++)
  83                 printf("%ld ", nums[i]);
  84         printf("\n");
  85
  86         free(nums);
  87         return 0;
  88 }