patch-ids.c

   1 #include "git-compat-util.h"
   2 #include "diff.h"
   3 #include "commit.h"
   4 #include "hash.h"
   5 #include "hash-lookup.h"
   6 #include "hex.h"
   7 #include "patch-ids.h"
   8
   9 static int patch_id_defined(struct commit *commit)
  10 {
  11         /* must be 0 or 1 parents */
  12         return !commit->parents || !commit->parents->next;
  13 }
  14
  15 int commit_patch_id(struct commit *commit, struct diff_options *options,
  16                     struct object_id *oid, int diff_header_only)
  17 {
  18         if (!patch_id_defined(commit))
  19                 return -1;
  20
  21         if (commit->parents)
  22                 diff_tree_oid(&commit->parents->item->object.oid,
  23                               &commit->object.oid, "", options);
  24         else
  25                 diff_root_tree_oid(&commit->object.oid, "", options);
  26         diffcore_std(options);
  27         return diff_flush_patch_id(options, oid, diff_header_only);
  28 }
  29
  30 /*
  31  * When we cannot load the full patch-id for both commits for whatever
  32  * reason, the function returns -1 (i.e. return error(...)). Despite
  33  * the "neq" in the name of this function, the caller only cares about
  34  * the return value being zero (a and b are equivalent) or non-zero (a
  35  * and b are different), and returning non-zero would keep both in the
  36  * result, even if they actually were equivalent, in order to err on
  37  * the side of safety.  The actual value being negative does not have
  38  * any significance; only that it is non-zero matters.
  39  */
  40 static int patch_id_neq(const void *cmpfn_data,
  41                         const struct hashmap_entry *eptr,
  42                         const struct hashmap_entry *entry_or_key,
  43                         const void *keydata UNUSED)
  44 {
  45         /* NEEDSWORK: const correctness? */
  46         struct diff_options *opt = (void *)cmpfn_data;
  47         struct patch_id *a, *b;
  48
  49         a = container_of(eptr, struct patch_id, ent);
  50         b = container_of(entry_or_key, struct patch_id, ent);
  51
  52         if (is_null_oid(&a->patch_id) &&
  53             commit_patch_id(a->commit, opt, &a->patch_id, 0))
  54                 return error("Could not get patch ID for %s",
  55                         oid_to_hex(&a->commit->object.oid));
  56         if (is_null_oid(&b->patch_id) &&
  57             commit_patch_id(b->commit, opt, &b->patch_id, 0))
  58                 return error("Could not get patch ID for %s",
  59                         oid_to_hex(&b->commit->object.oid));
  60         return !oideq(&a->patch_id, &b->patch_id);
  61 }
  62
  63 int init_patch_ids(struct repository *r, struct patch_ids *ids)
  64 {
  65         memset(ids, 0, sizeof(*ids));
  66         repo_diff_setup(r, &ids->diffopts);
  67         ids->diffopts.detect_rename = 0;
  68         ids->diffopts.flags.recursive = 1;
  69         diff_setup_done(&ids->diffopts);
  70         hashmap_init(&ids->patches, patch_id_neq, &ids->diffopts, 256);
  71         return 0;
  72 }
  73
  74 int free_patch_ids(struct patch_ids *ids)
  75 {
  76         hashmap_clear_and_free(&ids->patches, struct patch_id, ent);
  77         return 0;
  78 }
  79
  80 static int init_patch_id_entry(struct patch_id *patch,
  81                                struct commit *commit,
  82                                struct patch_ids *ids)
  83 {
  84         struct object_id header_only_patch_id;
  85
  86         patch->commit = commit;
  87         if (commit_patch_id(commit, &ids->diffopts, &header_only_patch_id, 1))
  88                 return -1;
  89
  90         hashmap_entry_init(&patch->ent, oidhash(&header_only_patch_id));
  91         return 0;
  92 }
  93
  94 struct patch_id *patch_id_iter_first(struct commit *commit,
  95                                      struct patch_ids *ids)
  96 {
  97         struct patch_id patch;
  98
  99         if (!patch_id_defined(commit))
 100                 return NULL;
 101
 102         memset(&patch, 0, sizeof(patch));
 103         if (init_patch_id_entry(&patch, commit, ids))
 104                 return NULL;
 105
 106         return hashmap_get_entry(&ids->patches, &patch, ent, NULL);
 107 }
 108
 109 struct patch_id *patch_id_iter_next(struct patch_id *cur,
 110                                     struct patch_ids *ids)
 111 {
 112         return hashmap_get_next_entry(&ids->patches, cur, ent);
 113 }
 114
 115 int has_commit_patch_id(struct commit *commit,
 116                         struct patch_ids *ids)
 117 {
 118         return !!patch_id_iter_first(commit, ids);
 119 }
 120
 121 struct patch_id *add_commit_patch_id(struct commit *commit,
 122                                      struct patch_ids *ids)
 123 {
 124         struct patch_id *key;
 125
 126         if (!patch_id_defined(commit))
 127                 return NULL;
 128
 129         CALLOC_ARRAY(key, 1);
 130         if (init_patch_id_entry(key, commit, ids)) {
 131                 free(key);
 132                 return NULL;
 133         }
 134
 135         hashmap_add(&ids->patches, &key->ent);
 136         return key;
 137 }