gbox-walk.c

   1 /* walk through gbox
   2  * Copyright (C) 2011  Kirill Smelkov <kirr@navytux.spb.ru>
   3  *
   4  * This program is free software: you can Use, Study, Modify and Redistribute it
   5  * under the terms of the GNU General Public License version 2. This program is
   6  * distributed WITHOUT ANY WARRANTY. See COPYING file for full License terms.
   7  */
   8
   9
  10 #include "navymail/gbox-walk.h"
  11
  12
  13 /* TODO die -> error codes */
  14 void prepare_gbox_walk(struct gbox_walk *w)
  15 {
  16         /* TODO convert to argv_array */
  17         const char *rev_argv[3];
  18         int rev_argc=0;
  19
  20         rev_argv[rev_argc++] = NULL;
  21         if (w->original_order)
  22                 rev_argv[rev_argc++] = "--reverse";
  23         rev_argv[rev_argc++] = w->gbox;
  24
  25
  26         init_revisions(&w->revs, NULL/*prefix - ok?*/);
  27         if (setup_revisions(rev_argc, rev_argv, &w->revs, NULL) != 1)
  28                 die("gbox-walk: setup revision failed");
  29
  30         if (prepare_revision_walk(&w->revs))
  31                 die("gbox-walk: revision walk setup failed");
  32
  33         w->tree = NULL;
  34         w->tree_entries.sha1 = NULL;    /* = SHA1_ARRAY_INIT */
  35         w->entry_idx = -1;
  36 }
  37
  38
  39 const unsigned char * /*sha1*/ next_gbox_entry(struct gbox_walk *w)
  40 {
  41         struct name_entry entry;
  42
  43 start:
  44         /* see, if we need to fetch next commit */
  45         if (!w->tree) {
  46                 struct commit *commit;
  47
  48                 commit = get_revision(&w->revs);
  49                 if (!commit)
  50                         return NULL;
  51
  52                 /* printf("%s\n", sha1_to_hex(commit->object.sha1)); */
  53                 w->tree = commit->tree;
  54                 if (parse_tree(w->tree))
  55                         die("gbox-walk: parse_tree failed");
  56
  57                 init_tree_desc(&w->tree_desc, w->tree->buffer, w->tree->size);
  58
  59
  60                 /* preload the tree for original order */
  61                 if (w->original_order) {
  62                         while (tree_entry(&w->tree_desc, &entry))
  63                                 sha1_array_append(&w->tree_entries, entry.sha1);
  64
  65                         w->entry_idx = w->tree_entries.nr - 1;
  66                 }
  67         }
  68
  69
  70         /* fast case - walking gbox in reverse order */
  71         if (!w->original_order) {
  72                 if (tree_entry(&w->tree_desc, &entry))
  73                         return entry.sha1;
  74         }
  75
  76         /* slow case - exporting mbox in original order */
  77         else {
  78                 if (w->entry_idx >= 0)
  79                         return w->tree_entries.sha1[w->entry_idx--];
  80
  81                 sha1_array_clear(&w->tree_entries);
  82         }
  83
  84
  85         /* restart from next commit */
  86         w->tree = NULL;
  87         goto start;
  88 }