object-file-convert: stop depending on `the_repository`

There are multiple sites in "object-file-convert.c" where we use the
global `the_repository` variable, either explicitly or implicitly by
using `the_hash_algo`. All of these callsites are transitively called
from `convert_object_file()`, which indeed has no repo as input.

Refactor the function so that it receives a repository as a parameter
and pass it through to all internal functions to get rid of the
dependency. Remove the `USE_THE_REPOSITORY_VARIABLE` define.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

builtin/tag.c

@@ -172,7 +172,7 @@ static int do_sign(struct strbuf *buffer, struct object_id **compat_oid,
 	if (compat) {
 		const struct git_hash_algo *algo = the_repository->hash_algo;
 
-		if (convert_object_file(&compat_buf, algo, compat,
+		if (convert_object_file(the_repository ,&compat_buf, algo, compat,
 					buffer->buf, buffer->len, OBJ_TAG, 1))
 			goto out;
 		if (sign_buffer(&compat_buf, &compat_sig, keyid))

commit.c

@@ -1380,7 +1380,7 @@ static int convert_commit_extra_headers(const struct commit_extra_header *orig,
 		struct commit_extra_header *new;
 		CALLOC_ARRAY(new, 1);
 		if (!strcmp(orig->key, "mergetag")) {
-			if (convert_object_file(&out, algo, compat,
+			if (convert_object_file(the_repository, &out, algo, compat,
 						orig->value, orig->len,
 						OBJ_TAG, 1)) {
 				free(new);

object-file-convert.c

@@ -1,4 +1,3 @@
-#define USE_THE_REPOSITORY_VARIABLE
 #define DISABLE_SIGN_COMPARE_WARNINGS
 
 #include "git-compat-util.h"
@@ -63,7 +62,8 @@ static int decode_tree_entry_raw(struct object_id *oid, const char **path,
 	return 0;
 }
 
-static int convert_tree_object(struct strbuf *out,
+static int convert_tree_object(struct repository *repo,
+			       struct strbuf *out,
 			       const struct git_hash_algo *from,
 			       const struct git_hash_algo *to,
 			       const char *buffer, size_t size)
@@ -78,7 +78,7 @@ static int convert_tree_object(struct strbuf *out,
 		if (decode_tree_entry_raw(&entry_oid, &path, &pathlen, from, p,
 					  end - p))
 			return error(_("failed to decode tree entry"));
-		if (repo_oid_to_algop(the_repository, &entry_oid, to, &mapped_oid))
+		if (repo_oid_to_algop(repo, &entry_oid, to, &mapped_oid))
 			return error(_("failed to map tree entry for %s"), oid_to_hex(&entry_oid));
 		strbuf_add(out, p, path - p);
 		strbuf_add(out, path, pathlen);
@@ -88,7 +88,8 @@ static int convert_tree_object(struct strbuf *out,
 	return 0;
 }
 
-static int convert_tag_object(struct strbuf *out,
+static int convert_tag_object(struct repository *repo,
+			      struct strbuf *out,
 			      const struct git_hash_algo *from,
 			      const struct git_hash_algo *to,
 			      const char *buffer, size_t size)
@@ -105,7 +106,7 @@ static int convert_tag_object(struct strbuf *out,
 		return error("bogus tag object");
 	if (parse_oid_hex_algop(buffer + 7, &oid, &p, from) < 0)
 		return error("bad tag object ID");
-	if (repo_oid_to_algop(the_repository, &oid, to, &mapped_oid))
+	if (repo_oid_to_algop(repo, &oid, to, &mapped_oid))
 		return error("unable to map tree %s in tag object",
 			     oid_to_hex(&oid));
 	size -= ((p + 1) - buffer);
@@ -139,7 +140,8 @@ static int convert_tag_object(struct strbuf *out,
 	return 0;
 }
 
-static int convert_commit_object(struct strbuf *out,
+static int convert_commit_object(struct repository *repo,
+				 struct strbuf *out,
 				 const struct git_hash_algo *from,
 				 const struct git_hash_algo *to,
 				 const char *buffer, size_t size)
@@ -165,7 +167,7 @@ static int convert_commit_object(struct strbuf *out,
 			    (p != eol))
 				return error(_("bad %s in commit"), "tree");
 
-			if (repo_oid_to_algop(the_repository, &oid, to, &mapped_oid))
+			if (repo_oid_to_algop(repo, &oid, to, &mapped_oid))
 				return error(_("unable to map %s %s in commit object"),
 					     "tree", oid_to_hex(&oid));
 			strbuf_addf(out, "tree %s\n", oid_to_hex(&mapped_oid));
@@ -177,7 +179,7 @@ static int convert_commit_object(struct strbuf *out,
 			    (p != eol))
 				return error(_("bad %s in commit"), "parent");
 
-			if (repo_oid_to_algop(the_repository, &oid, to, &mapped_oid))
+			if (repo_oid_to_algop(repo, &oid, to, &mapped_oid))
 				return error(_("unable to map %s %s in commit object"),
 					     "parent", oid_to_hex(&oid));
 
@@ -202,7 +204,7 @@ static int convert_commit_object(struct strbuf *out,
 			}
 
 			/* Compute the new tag object */
-			if (convert_tag_object(&new_tag, from, to, tag.buf, tag.len)) {
+			if (convert_tag_object(repo, &new_tag, from, to, tag.buf, tag.len)) {
 				strbuf_release(&tag);
 				strbuf_release(&new_tag);
 				return -1;
@@ -241,7 +243,8 @@ static int convert_commit_object(struct strbuf *out,
 	return 0;
 }
 
-int convert_object_file(struct strbuf *outbuf,
+int convert_object_file(struct repository *repo,
+			struct strbuf *outbuf,
 			const struct git_hash_algo *from,
 			const struct git_hash_algo *to,
 			const void *buf, size_t len,
@@ -256,13 +259,13 @@ int convert_object_file(struct strbuf *outbuf,
 
 	switch (type) {
 	case OBJ_COMMIT:
-		ret = convert_commit_object(outbuf, from, to, buf, len);
+		ret = convert_commit_object(repo, outbuf, from, to, buf, len);
 		break;
 	case OBJ_TREE:
-		ret = convert_tree_object(outbuf, from, to, buf, len);
+		ret = convert_tree_object(repo, outbuf, from, to, buf, len);
 		break;
 	case OBJ_TAG:
-		ret = convert_tag_object(outbuf, from, to, buf, len);
+		ret = convert_tag_object(repo, outbuf, from, to, buf, len);
 		break;
 	default:
 		/* Not implemented yet, so fail. */

object-file-convert.h

@@ -14,7 +14,8 @@ int repo_oid_to_algop(struct repository *repo, const struct object_id *src,
  * Convert an object file from one hash algorithm to another algorithm.
  * Return -1 on failure, 0 on success.
  */
-int convert_object_file(struct strbuf *outbuf,
+int convert_object_file(struct repository *repo,
+			struct strbuf *outbuf,
 			const struct git_hash_algo *from,
 			const struct git_hash_algo *to,
 			const void *buf, size_t len,

object-file.c

@@ -1793,7 +1793,7 @@ static int oid_object_info_convert(struct repository *r,
 		if (type == -1)
 			return -1;
 		if (type != OBJ_BLOB) {
-			ret = convert_object_file(&outbuf,
+			ret = convert_object_file(the_repository, &outbuf,
 						  the_hash_algo, input_algo,
 						  content, size, type, !do_die);
 			free(content);
@@ -2510,7 +2510,7 @@ int write_object_file_flags(const void *buf, unsigned long len,
 			hash_object_file(compat, buf, len, type, &compat_oid);
 		else {
 			struct strbuf converted = STRBUF_INIT;
-			convert_object_file(&converted, algo, compat,
+			convert_object_file(the_repository, &converted, algo, compat,
 					    buf, len, type, 0);
 			hash_object_file(compat, converted.buf, converted.len,
 					 type, &compat_oid);
@@ -2550,7 +2550,8 @@ int write_object_file_literally(const void *buf, unsigned long len,
 					 &compat_oid);
 		else if (compat_type != -1) {
 			struct strbuf converted = STRBUF_INIT;
-			convert_object_file(&converted, algo, compat,
+			convert_object_file(the_repository,
+					    &converted, algo, compat,
 					    buf, len, compat_type, 0);
 			hash_object_file(compat, converted.buf, converted.len,
 					 compat_type, &compat_oid);