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 "git-compat-util.h"
   6 #include "gettext.h"
   7 #include "diff.h"
   8 #include "diffcore.h"
   9
  10 void diffcore_rotate(struct diff_options *opt)
  11 {
  12         struct diff_queue_struct *q = &diff_queued_diff;
  13         struct diff_queue_struct outq = DIFF_QUEUE_INIT;
  14         int rotate_to, i;
  15
  16         if (!q->nr)
  17                 return;
  18
  19         for (i = 0; i < q->nr; i++) {
  20                 int cmp = strcmp(opt->rotate_to, q->queue[i]->two->path);
  21                 if (!cmp)
  22                         break; /* exact match */
  23                 if (!opt->rotate_to_strict && cmp < 0)
  24                         break; /* q->queue[i] is now past the target pathname */
  25         }
  26
  27         if (q->nr <= i) {
  28                 /* we did not find the specified path */
  29                 if (opt->rotate_to_strict)
  30                         die(_("No such path '%s' in the diff"), opt->rotate_to);
  31                 return;
  32         }
  33
  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 }