diffcore-rotate.c

   1 /*
   2  * Copyright (C) 2021, Google LLC.
   3  * Based on diffcore-order.c, which is Copyright (C) 2005, Junio C Hamano
   4  */
   5 #include "cache.h"
   6 #include "diff.h"
   7 #include "diffcore.h"
   8
   9 void diffcore_rotate(struct diff_options *opt)
  10 {
  11         struct diff_queue_struct *q = &diff_queued_diff;
  12         struct diff_queue_struct outq;
  13         int rotate_to, i;
  14
  15         if (!q->nr)
  16                 return;
  17
  18         for (i = 0; i < q->nr; i++) {
  19                 int cmp = strcmp(opt->rotate_to, q->queue[i]->two->path);
  20                 if (!cmp)
  21                         break; /* exact match */
  22                 if (!opt->rotate_to_strict && cmp < 0)
  23                         break; /* q->queue[i] is now past the target pathname */
  24         }
  25
  26         if (q->nr <= i) {
  27                 /* we did not find the specified path */
  28                 if (opt->rotate_to_strict)
  29                         die(_("No such path '%s' in the diff"), opt->rotate_to);
  30                 return;
  31         }
  32
  33         DIFF_QUEUE_CLEAR(&outq);
  34         rotate_to = i;
  35
  36         for (i = rotate_to; i < q->nr; i++)
  37                 diff_q(&outq, q->queue[i]);
  38         for (i = 0; i < rotate_to; i++) {
  39                 if (opt->skip_instead_of_rotate)
  40                         diff_free_filepair(q->queue[i]);
  41                 else
  42                         diff_q(&outq, q->queue[i]);
  43         }
  44         free(q->queue);
  45         *q = outq;
  46 }