Andrew's git / gitweb.git /
082412aca66be6ce826034c5177e2f7f4b3bda58
   1#include "cache.h"
   2#include "diff.h"
   3#include "commit.h"
   4#include "sha1-lookup.h"
   5#include "patch-ids.h"
   6
   7int commit_patch_id(struct commit *commit, struct diff_options *options,
   8                    unsigned char *sha1, int diff_header_only)
   9{
  10        if (commit->parents)
  11                diff_tree_sha1(commit->parents->item->object.oid.hash,
  12                               commit->object.oid.hash, "", options);
  13        else
  14                diff_root_tree_sha1(commit->object.oid.hash, "", options);
  15        diffcore_std(options);
  16        return diff_flush_patch_id(options, sha1, diff_header_only);
  17}
  18
  19/*
  20 * When we cannot load the full patch-id for both commits for whatever
  21 * reason, the function returns -1 (i.e. return error(...)). Despite
  22 * the "cmp" in the name of this function, the caller only cares about
  23 * the return value being zero (a and b are equivalent) or non-zero (a
  24 * and b are different), and returning non-zero would keep both in the
  25 * result, even if they actually were equivalent, in order to err on
  26 * the side of safety.  The actual value being negative does not have
  27 * any significance; only that it is non-zero matters.
  28 */
  29static int patch_id_cmp(struct patch_id *a,
  30                        struct patch_id *b,
  31                        struct diff_options *opt)
  32{
  33        if (is_null_sha1(a->patch_id) &&
  34            commit_patch_id(a->commit, opt, a->patch_id, 0))
  35                return error("Could not get patch ID for %s",
  36                        oid_to_hex(&a->commit->object.oid));
  37        if (is_null_sha1(b->patch_id) &&
  38            commit_patch_id(b->commit, opt, b->patch_id, 0))
  39                return error("Could not get patch ID for %s",
  40                        oid_to_hex(&b->commit->object.oid));
  41        return hashcmp(a->patch_id, b->patch_id);
  42}
  43
  44int init_patch_ids(struct patch_ids *ids)
  45{
  46        memset(ids, 0, sizeof(*ids));
  47        diff_setup(&ids->diffopts);
  48        DIFF_OPT_SET(&ids->diffopts, RECURSIVE);
  49        diff_setup_done(&ids->diffopts);
  50        hashmap_init(&ids->patches, (hashmap_cmp_fn)patch_id_cmp, 256);
  51        return 0;
  52}
  53
  54int free_patch_ids(struct patch_ids *ids)
  55{
  56        hashmap_free(&ids->patches, 1);
  57        return 0;
  58}
  59
  60static int init_patch_id_entry(struct patch_id *patch,
  61                               struct commit *commit,
  62                               struct patch_ids *ids)
  63{
  64        unsigned char header_only_patch_id[GIT_SHA1_RAWSZ];
  65
  66        patch->commit = commit;
  67        if (commit_patch_id(commit, &ids->diffopts, header_only_patch_id, 1))
  68                return -1;
  69
  70        hashmap_entry_init(patch, sha1hash(header_only_patch_id));
  71        return 0;
  72}
  73
  74struct patch_id *has_commit_patch_id(struct commit *commit,
  75                                     struct patch_ids *ids)
  76{
  77        struct patch_id patch;
  78
  79        memset(&patch, 0, sizeof(patch));
  80        if (init_patch_id_entry(&patch, commit, ids))
  81                return NULL;
  82
  83        return hashmap_get(&ids->patches, &patch, &ids->diffopts);
  84}
  85
  86struct patch_id *add_commit_patch_id(struct commit *commit,
  87                                     struct patch_ids *ids)
  88{
  89        struct patch_id *key = xcalloc(1, sizeof(*key));
  90
  91        if (init_patch_id_entry(key, commit, ids)) {
  92                free(key);
  93                return NULL;
  94        }
  95
  96        hashmap_add(&ids->patches, key);
  97        return key;
  98}