t/helper/test-mergesort.c

   1 #include "test-tool.h"
   2 #include "cache.h"
   3 #include "mergesort.h"
   4
   5 struct line {
   6         char *text;
   7         struct line *next;
   8 };
   9
  10 static void *get_next(const void *a)
  11 {
  12         return ((const struct line *)a)->next;
  13 }
  14
  15 static void set_next(void *a, void *b)
  16 {
  17         ((struct line *)a)->next = b;
  18 }
  19
  20 static int compare_strings(const void *a, const void *b)
  21 {
  22         const struct line *x = a, *y = b;
  23         return strcmp(x->text, y->text);
  24 }
  25
  26 int cmd__mergesort(int argc, const char **argv)
  27 {
  28         struct line *line, *p = NULL, *lines = NULL;
  29         struct strbuf sb = STRBUF_INIT;
  30
  31         for (;;) {
  32                 if (strbuf_getwholeline(&sb, stdin, '\n'))
  33                         break;
  34                 line = xmalloc(sizeof(struct line));
  35                 line->text = strbuf_detach(&sb, NULL);
  36                 if (p) {
  37                         line->next = p->next;
  38                         p->next = line;
  39                 } else {
  40                         line->next = NULL;
  41                         lines = line;
  42                 }
  43                 p = line;
  44         }
  45
  46         lines = llist_mergesort(lines, get_next, set_next, compare_strings);
  47
  48         while (lines) {
  49                 printf("%s", lines->text);
  50                 lines = lines->next;
  51         }
  52         return 0;
  53 }