commit: copy merged signed tags to headers of merge commit
Now MERGE_HEAD records the tag objects without peeling, we could record the result of manual conflict resolution via "git commit" without losing the tag information. Introduce a new "mergetag" multi-line header field to the commit object, and use it to store the entire contents of each signed tag merged. A commit header that has a multi-line payload begins with the header tag (e.g. "mergetag" in this case), SP, the first line of payload, LF, and all the remaining lines have a SP inserted at the beginning. In hindsight, it would have been better to make "merge --continue" as the way to continue from such an interrupted merge, not "commit", but this is a backward compatibility baggage we would need to carry around for now. Signed-off-by: Junio C Hamano <gitster@pobox.com>
Junio C Hamano committed
Nov 7, 2011 at 16:21 UTC
5231c633f2e54723d53a8cd928d9bc98b39dc35f
3 files changed
+116
-11
builtin/commit.c
+5
-5
@@ -1425,7 +1425,6 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
1425
pptr = &commit_list_insert(c->item, pptr)->next;
1426
} else if (whence == FROM_MERGE) {
1427
struct strbuf m = STRBUF_INIT;
1428
- struct commit *commit;
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FILE *fp;
1429
1430
if (!reflog_msg)
@@ -1436,11 +1435,12 @@ int cmd_commit(int argc, const char **argv, const char *prefix)
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die_errno(_("could not open '%s' for reading"),
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git_path("MERGE_HEAD"));
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while (strbuf_getline(&m, fp, '\n') != EOF) {
1439
- unsigned char sha1[20];
1440
- if (get_sha1_hex(m.buf, sha1) < 0)
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+ struct commit *parent;
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+
1440
+ parent = get_merge_parent(m.buf);
1441
+ if (!parent)
1442
die(_("Corrupt MERGE_HEAD file (%s)"), m.buf);
1442
- commit = lookup_commit_or_die(sha1, "MERGE_HEAD");
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- pptr = &commit_list_insert(commit, pptr)->next;
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+ pptr = &commit_list_insert(parent, pptr)->next;
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}
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fclose(fp);
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strbuf_release(&m);
commit.c
+92
-4
@@ -840,14 +840,95 @@ struct commit_list *reduce_heads(struct commit_list *heads)
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return result;
841
}
842
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+static void handle_signed_tag(struct commit *parent, struct commit_extra_header ***tail)
844
+{
845
+ struct merge_remote_desc *desc;
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+ struct commit_extra_header *mergetag;
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+ char *buf;
848
+ unsigned long size, len;
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+ enum object_type type;
850
+
851
+ desc = merge_remote_util(parent);
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+ if (!desc || !desc->obj)
853
+ return;
854
+ buf = read_sha1_file(desc->obj->sha1, &type, &size);
855
+ if (!buf || type != OBJ_TAG)
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+ goto free_return;
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+ len = parse_signature(buf, size);
858
+ if (size == len)
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+ goto free_return;
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+ /*
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+ * We could verify this signature and either omit the tag when
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+ * it does not validate, but the integrator may not have the
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+ * public key of the signer of the tag he is merging, while a
864
+ * later auditor may have it while auditing, so let's not run
865
+ * verify-signed-buffer here for now...
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+ *
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+ * if (verify_signed_buffer(buf, len, buf + len, size - len, ...))
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+ * warn("warning: signed tag unverified.");
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+ */
870
+ mergetag = xcalloc(1, sizeof(*mergetag));
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+ mergetag->key = xstrdup("mergetag");
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+ mergetag->value = buf;
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+ mergetag->len = size;
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+
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+ **tail = mergetag;
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+ *tail = &mergetag->next;
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+ return;
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+
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+free_return:
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+ free(buf);
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+}
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+
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+void append_merge_tag_headers(struct commit_list *parents,
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+ struct commit_extra_header ***tail)
885
+{
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+ while (parents) {
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+ struct commit *parent = parents->item;
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+ handle_signed_tag(parent, tail);
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+ parents = parents->next;
890
+ }
891
+}
892
+
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+static void add_extra_header(struct strbuf *buffer,
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+ struct commit_extra_header *extra)
895
+{
896
+ strbuf_addstr(buffer, extra->key);
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+ strbuf_add_lines(buffer, " ", extra->value, extra->len);
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+}
899
+
900
+void free_commit_extra_headers(struct commit_extra_header *extra)
901
+{
902
+ while (extra) {
903
+ struct commit_extra_header *next = extra->next;
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+ free(extra->key);
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+ free(extra->value);
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+ free(extra);
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+ extra = next;
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+ }
909
+}
910
+
911
+int commit_tree(const char *msg, unsigned char *tree,
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+ struct commit_list *parents, unsigned char *ret,
913
+ const char *author)
914
+{
915
+ struct commit_extra_header *extra = NULL, **tail = &extra;
916
+ int result;
917
+
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+ append_merge_tag_headers(parents, &tail);
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+ result = commit_tree_extended(msg, tree, parents, ret, author, extra);
920
+ free_commit_extra_headers(extra);
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+ return result;
922
+}
923
+
924
static const char commit_utf8_warn[] =
925
"Warning: commit message does not conform to UTF-8.\n"
926
"You may want to amend it after fixing the message, or set the config\n"
927
"variable i18n.commitencoding to the encoding your project uses.\n";
928
848
-int commit_tree(const char *msg, unsigned char *tree,
849
- struct commit_list *parents, unsigned char *ret,
850
- const char *author)
929
+int commit_tree_extended(const char *msg, unsigned char *tree,
930
+ struct commit_list *parents, unsigned char *ret,
931
+ const char *author, struct commit_extra_header *extra)
932
{
933
int result;
934
int encoding_is_utf8;
@@ -868,8 +949,10 @@ int commit_tree(const char *msg, unsigned char *tree,
949
*/
950
while (parents) {
951
struct commit_list *next = parents->next;
952
+ struct commit *parent = parents->item;
953
+
954
strbuf_addf(&buffer, "parent %s\n",
872
- sha1_to_hex(parents->item->object.sha1));
955
+ sha1_to_hex(parent->object.sha1));
956
free(parents);
957
parents = next;
958
}
@@ -881,6 +964,11 @@ int commit_tree(const char *msg, unsigned char *tree,
964
strbuf_addf(&buffer, "committer %s\n", git_committer_info(IDENT_ERROR_ON_NO_NAME));
965
if (!encoding_is_utf8)
966
strbuf_addf(&buffer, "encoding %s\n", git_commit_encoding);
967
+
968
+ while (extra) {
969
+ add_extra_header(&buffer, extra);
970
+ extra = extra->next;
971
+ }
972
strbuf_addch(&buffer, '\n');
973
974
/* And add the comment */
commit.h
+19
-2
@@ -181,9 +181,26 @@ static inline int single_parent(struct commit *commit)
181
182
struct commit_list *reduce_heads(struct commit_list *heads);
183
184
+struct commit_extra_header {
185
+ struct commit_extra_header *next;
186
+ char *key;
187
+ char *value;
188
+ size_t len;
189
+};
190
+
191
+extern void append_merge_tag_headers(struct commit_list *parents,
192
+ struct commit_extra_header ***tail);
193
+
194
extern int commit_tree(const char *msg, unsigned char *tree,
185
- struct commit_list *parents, unsigned char *ret,
186
- const char *author);
195
+ struct commit_list *parents, unsigned char *ret,
196
+ const char *author);
197
+
198
+extern int commit_tree_extended(const char *msg, unsigned char *tree,
199
+ struct commit_list *parents, unsigned char *ret,
200
+ const char *author,
201
+ struct commit_extra_header *);
202
+
203
+extern void free_commit_extra_headers(struct commit_extra_header *extra);
204
205
struct merge_remote_desc {
206
struct object *obj; /* the named object, could be a tag */