git/patch-ids.c
Stefan Beller 3da492f808 patch-ids.c: use hashmap correctly
As alluded to in the previous patch, the code in patch-ids.c is
using the hashmaps API wrong.

Luckily we do not have a bug, as all hashmap functionality that we use
here (hashmap_get) passes through the keydata.  If hashmap_get_next were
to be used, a bug would occur as that passes NULL for the key_data.

So instead use the hashmap API correctly and provide the caller required
data in the compare function via the first argument that always gets
passed and was setup via the hashmap_init function.

Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-06-30 13:11:54 -07:00

118 lines
3.1 KiB
C

#include "cache.h"
#include "diff.h"
#include "commit.h"
#include "sha1-lookup.h"
#include "patch-ids.h"
static int patch_id_defined(struct commit *commit)
{
/* must be 0 or 1 parents */
return !commit->parents || !commit->parents->next;
}
int commit_patch_id(struct commit *commit, struct diff_options *options,
struct object_id *oid, int diff_header_only)
{
if (!patch_id_defined(commit))
return -1;
if (commit->parents)
diff_tree_oid(&commit->parents->item->object.oid,
&commit->object.oid, "", options);
else
diff_root_tree_oid(&commit->object.oid, "", options);
diffcore_std(options);
return diff_flush_patch_id(options, oid, diff_header_only);
}
/*
* When we cannot load the full patch-id for both commits for whatever
* reason, the function returns -1 (i.e. return error(...)). Despite
* the "cmp" in the name of this function, the caller only cares about
* the return value being zero (a and b are equivalent) or non-zero (a
* and b are different), and returning non-zero would keep both in the
* result, even if they actually were equivalent, in order to err on
* the side of safety. The actual value being negative does not have
* any significance; only that it is non-zero matters.
*/
static int patch_id_cmp(struct diff_options *opt,
struct patch_id *a,
struct patch_id *b,
const void *unused_keydata)
{
if (is_null_oid(&a->patch_id) &&
commit_patch_id(a->commit, opt, &a->patch_id, 0))
return error("Could not get patch ID for %s",
oid_to_hex(&a->commit->object.oid));
if (is_null_oid(&b->patch_id) &&
commit_patch_id(b->commit, opt, &b->patch_id, 0))
return error("Could not get patch ID for %s",
oid_to_hex(&b->commit->object.oid));
return oidcmp(&a->patch_id, &b->patch_id);
}
int init_patch_ids(struct patch_ids *ids)
{
memset(ids, 0, sizeof(*ids));
diff_setup(&ids->diffopts);
ids->diffopts.detect_rename = 0;
DIFF_OPT_SET(&ids->diffopts, RECURSIVE);
diff_setup_done(&ids->diffopts);
hashmap_init(&ids->patches, (hashmap_cmp_fn)patch_id_cmp,
&ids->diffopts, 256);
return 0;
}
int free_patch_ids(struct patch_ids *ids)
{
hashmap_free(&ids->patches, 1);
return 0;
}
static int init_patch_id_entry(struct patch_id *patch,
struct commit *commit,
struct patch_ids *ids)
{
struct object_id header_only_patch_id;
patch->commit = commit;
if (commit_patch_id(commit, &ids->diffopts, &header_only_patch_id, 1))
return -1;
hashmap_entry_init(patch, sha1hash(header_only_patch_id.hash));
return 0;
}
struct patch_id *has_commit_patch_id(struct commit *commit,
struct patch_ids *ids)
{
struct patch_id patch;
if (!patch_id_defined(commit))
return NULL;
memset(&patch, 0, sizeof(patch));
if (init_patch_id_entry(&patch, commit, ids))
return NULL;
return hashmap_get(&ids->patches, &patch, NULL);
}
struct patch_id *add_commit_patch_id(struct commit *commit,
struct patch_ids *ids)
{
struct patch_id *key;
if (!patch_id_defined(commit))
return NULL;
key = xcalloc(1, sizeof(*key));
if (init_patch_id_entry(key, commit, ids)) {
free(key);
return NULL;
}
hashmap_add(&ids->patches, key);
return key;
}