[PATCH 01/15] sha1-file: allow hashing objects literally with any algorithm

From

brian m. carlson <sandals@crustytoothpaste.net>

Date

Apr 10, 2021, 15:21 UTC

Message-ID

<20210410152140.3525040-2-sandals@crustytoothpaste.net>

In-Reply-To

<20210410152140.3525040-1-sandals@crustytoothpaste.net>

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
---
 object-file.c  | 16 ++++++++++++++--
 object-store.h |  3 +++
 2 files changed, 17 insertions(+), 2 deletions(-)

diff --git a/object-file.c b/object-file.c
index 624af408cd..f5847ee20f 100644
--- a/object-file.c
+++ b/object-file.c
@@ -1957,6 +1957,15 @@ int write_object_file(const void *buf, unsigned long len, const char *type,
 int hash_object_file_literally(const void *buf, unsigned long len,
 			       const char *type, struct object_id *oid,
 			       unsigned flags)
+{
+	return hash_object_file_literally_algop(buf, len, type, oid, flags,
+						the_hash_algo);
+}
+
+int hash_object_file_literally_algop(const void *buf, unsigned long len,
+				     const char *type, struct object_id *oid,
+				     unsigned flags,
+				     const struct git_hash_algo *algo)
 {
 	char *header;
 	int hdrlen, status = 0;
@@ -1964,11 +1973,14 @@ int hash_object_file_literally(const void *buf, unsigned long len,
 	/* type string, SP, %lu of the length plus NUL must fit this */
 	hdrlen = strlen(type) + MAX_HEADER_LEN;
 	header = xmalloc(hdrlen);
-	write_object_file_prepare(the_hash_algo, buf, len, type, oid, header,
-				  &hdrlen);
+	write_object_file_prepare(algo, buf, len, type, oid, header, &hdrlen);
 
 	if (!(flags & HASH_WRITE_OBJECT))
 		goto cleanup;
+	if (algo->format_id != the_hash_algo->format_id) {
+		status = -1;
+		goto cleanup;
+	}
 	if (freshen_packed_object(oid) || freshen_loose_object(oid))
 		goto cleanup;
 	status = write_loose_object(oid, header, hdrlen, buf, len, 0);
diff --git a/object-store.h b/object-store.h
index ec32c23dcb..f95d03a7f5 100644
--- a/object-store.h
+++ b/object-store.h
@@ -221,6 +221,9 @@ int hash_object_file_literally(const void *buf, unsigned long len,
 			       const char *type, struct object_id *oid,
 			       unsigned flags);
 
+int hash_object_file_literally_algop(const void *buf, unsigned long len,
+				     const char *type, struct object_id *oid,
+				     unsigned flags, const struct git_hash_algo *algo);
 /*
  * Add an object file to the in-memory object store, without writing it
  * to disk.