format-patch: make --base patch-id output stable
We weren't flushing the context each time we processed a hunk in the
patch-id generation code in diff.c, but we were doing that when we
generated "stable" patch-ids with the 'patch-id' tool. Let's port that
similar logic over from patch-id.c into diff.c so we can get the same
hash when we're generating patch-ids for 'format-patch --base=' types of
command invocations.
Cc: Xiaolong Ye <xiaolong.ye@intel.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/diff.c b/diff.c
index 4d3cf83..8e3675b 100644
--- a/diff.c
+++ b/diff.c
@@ -5988,6 +5988,22 @@ static int remove_space(char *line, int len)
return dst - line;
}
+void flush_one_hunk(struct object_id *result, git_SHA_CTX *ctx)
+{
+ unsigned char hash[GIT_MAX_RAWSZ];
+ unsigned short carry = 0;
+ int i;
+
+ git_SHA1_Final(hash, ctx);
+ git_SHA1_Init(ctx);
+ /* 20-byte sum, with carry */
+ for (i = 0; i < GIT_SHA1_RAWSZ; ++i) {
+ carry += result->hash[i] + hash[i];
+ result->hash[i] = carry;
+ carry >>= 8;
+ }
+}
+
static void patch_id_consume(void *priv, char *line, unsigned long len)
{
struct patch_id_t *data = priv;
@@ -6012,8 +6028,8 @@ static void patch_id_add_mode(git_SHA_CTX *ctx, unsigned mode)
git_SHA1_Update(ctx, buf, len);
}
-/* returns 0 upon success, and writes result into sha1 */
-static int diff_get_patch_id(struct diff_options *options, struct object_id *oid, int diff_header_only)
+/* returns 0 upon success, and writes result into oid */
+static int diff_get_patch_id(struct diff_options *options, struct object_id *oid, int diff_header_only, int stable)
{
struct diff_queue_struct *q = &diff_queued_diff;
int i;
@@ -6023,6 +6039,7 @@ static int diff_get_patch_id(struct diff_options *options, struct object_id *oid
git_SHA1_Init(&ctx);
memset(&data, 0, sizeof(struct patch_id_t));
data.ctx = &ctx;
+ oidclr(oid);
for (i = 0; i < q->nr; i++) {
xpparam_t xpp;
@@ -6098,17 +6115,22 @@ static int diff_get_patch_id(struct diff_options *options, struct object_id *oid
patch_id_consume, &data, &xpp, &xecfg))
return error("unable to generate patch-id diff for %s",
p->one->path);
+
+ if (stable)
+ flush_one_hunk(oid, &ctx);
}
- git_SHA1_Final(oid->hash, &ctx);
+ if (!stable)
+ git_SHA1_Final(oid->hash, &ctx);
+
return 0;
}
-int diff_flush_patch_id(struct diff_options *options, struct object_id *oid, int diff_header_only)
+int diff_flush_patch_id(struct diff_options *options, struct object_id *oid, int diff_header_only, int stable)
{
struct diff_queue_struct *q = &diff_queued_diff;
int i;
- int result = diff_get_patch_id(options, oid, diff_header_only);
+ int result = diff_get_patch_id(options, oid, diff_header_only, stable);
for (i = 0; i < q->nr; i++)
diff_free_filepair(q->queue[i]);
