patch-ids.c

   1 #include "cache.h"
   2 #include "diff.h"
   3 #include "commit.h"
   4 #include "sha1-lookup.h"
   5 #include "patch-ids.h"
   6
   7 static int commit_patch_id(struct commit *commit, struct diff_options *options,
   8                     unsigned char *sha1)
   9 {
  10         if (commit->parents)
  11                 diff_tree_sha1(commit->parents->item->object.sha1,
  12                                commit->object.sha1, "", options);
  13         else
  14                 diff_root_tree_sha1(commit->object.sha1, "", options);
  15         diffcore_std(options);
  16         return diff_flush_patch_id(options, sha1);
  17 }
  18
  19 static const unsigned char *patch_id_access(size_t index, void *table)
  20 {
  21         struct patch_id **id_table = table;
  22         return id_table[index]->patch_id;
  23 }
  24
  25 static int patch_pos(struct patch_id **table, int nr, const unsigned char *id)
  26 {
  27         return sha1_pos(id, table, nr, patch_id_access);
  28 }
  29
  30 #define BUCKET_SIZE 190 /* 190 * 21 = 3990, with slop close enough to 4K */
  31 struct patch_id_bucket {
  32         struct patch_id_bucket *next;
  33         int nr;
  34         struct patch_id bucket[BUCKET_SIZE];
  35 };
  36
  37 int init_patch_ids(struct patch_ids *ids)
  38 {
  39         memset(ids, 0, sizeof(*ids));
  40         diff_setup(&ids->diffopts);
  41         DIFF_OPT_SET(&ids->diffopts, RECURSIVE);
  42         if (diff_setup_done(&ids->diffopts) < 0)
  43                 return error("diff_setup_done failed");
  44         return 0;
  45 }
  46
  47 int free_patch_ids(struct patch_ids *ids)
  48 {
  49         struct patch_id_bucket *next, *patches;
  50
  51         free(ids->table);
  52         for (patches = ids->patches; patches; patches = next) {
  53                 next = patches->next;
  54                 free(patches);
  55         }
  56         return 0;
  57 }
  58
  59 static struct patch_id *add_commit(struct commit *commit,
  60                                    struct patch_ids *ids,
  61                                    int no_add)
  62 {
  63         struct patch_id_bucket *bucket;
  64         struct patch_id *ent;
  65         unsigned char sha1[20];
  66         int pos;
  67
  68         if (commit_patch_id(commit, &ids->diffopts, sha1))
  69                 return NULL;
  70         pos = patch_pos(ids->table, ids->nr, sha1);
  71         if (0 <= pos)
  72                 return ids->table[pos];
  73         if (no_add)
  74                 return NULL;
  75
  76         pos = -1 - pos;
  77
  78         bucket = ids->patches;
  79         if (!bucket || (BUCKET_SIZE <= bucket->nr)) {
  80                 bucket = xcalloc(1, sizeof(*bucket));
  81                 bucket->next = ids->patches;
  82                 ids->patches = bucket;
  83         }
  84         ent = &bucket->bucket[bucket->nr++];
  85         hashcpy(ent->patch_id, sha1);
  86
  87         if (ids->alloc <= ids->nr) {
  88                 ids->alloc = alloc_nr(ids->nr);
  89                 ids->table = xrealloc(ids->table, sizeof(ent) * ids->alloc);
  90         }
  91         if (pos < ids->nr)
  92                 memmove(ids->table + pos + 1, ids->table + pos,
  93                         sizeof(ent) * (ids->nr - pos));
  94         ids->nr++;
  95         ids->table[pos] = ent;
  96         return ids->table[pos];
  97 }
  98
  99 struct patch_id *has_commit_patch_id(struct commit *commit,
 100                                      struct patch_ids *ids)
 101 {
 102         return add_commit(commit, ids, 1);
 103 }
 104
 105 struct patch_id *add_commit_patch_id(struct commit *commit,
 106                                      struct patch_ids *ids)
 107 {
 108         return add_commit(commit, ids, 0);
 109 }