Merge pull request #216 from glesserd/development

git_tag_create{,_o,_frombuffer} correction and improvement

include/git2/tag.h

@@ -152,7 +152,9 @@ GIT_EXTERN(const char *) git_tag_message(git_tag *t);
  * Create a new tag in the repository from an OID
  *
  * @param oid Pointer where to store the OID of the
- *	newly created tag
+ * newly created tag. If the tag already exists, this parameter
+ * will be the oid of the existed tag, and the function will
+ * return a GIT_EEXISTS error code.
  *
  * @param repo Repository where to store the tag
  *

src/tag.c

@@ -180,45 +180,30 @@ static int retreive_tag_reference(git_reference **tag_reference_out, char *ref_n
 	return GIT_SUCCESS;
 }
 
-static int tag_create(
-		git_oid *oid,
-		git_repository *repo,
-		const char *tag_name,
+/* tag_reference_out will contain the reference of the tag if exists, otherwise NULL */
+static int tag_valid_in_odb(
+	git_reference **tag_reference_out,
+	char *ref_name_out,
 	const git_oid *target,
 	git_otype target_type,
-		const git_signature *tagger,
-		const char *message,
-		int allow_ref_overwrite)
-{
-	size_t final_size = 0;
-	git_odb_stream *stream;
+	git_repository *repo,
+	const char *tag_name) {
 	
-	const char *type_str;
-	char *tagger_str;
-	git_reference *new_ref;
+	int error;
 	
-	char ref_name[MAX_GITDIR_TREE_STRUCTURE_PATH_LENGTH];
+	*tag_reference_out = NULL;
 	
-	int type_str_len, tag_name_len, tagger_str_len, message_len;
-	int error, should_update_ref = 0;
 	
-	/** Ensure the tag name doesn't conflict with an already existing 
-	    reference unless overwriting has explictly been requested **/
-	error = retreive_tag_reference(&new_ref, ref_name, repo, tag_name);
+	error = retreive_tag_reference(tag_reference_out, ref_name_out, repo, tag_name);
 	
 	switch (error) {
 		case GIT_SUCCESS:
-		if (!allow_ref_overwrite)
-			return GIT_EEXISTS;	
-		should_update_ref = 1;
-		
 		/* Fall trough */
-
 		case GIT_ENOTFOUND: 
 			break;
 		
 		default:
-		return error == GIT_SUCCESS ? GIT_SUCCESS : git__rethrow(error, "Failed to create tag");
+			return git__rethrow(error, "Failed to create tag");
 	}
 	
 	if (!git_odb_exists(repo->db, target))
@@ -232,6 +217,45 @@ static int tag_create(
 			return git__rethrow(error, "Failed to create tag");
 	}
 	
+	return GIT_SUCCESS;
+}
+
+static int tag_create(
+		git_oid *oid,
+		git_repository *repo,
+		const char *tag_name,
+		const git_oid *target,
+		git_otype target_type,
+		const git_signature *tagger,
+		const char *message,
+		int allow_ref_overwrite)
+{
+	size_t final_size = 0;
+	git_odb_stream *stream;
+
+	const char *type_str;
+	char *tagger_str;
+	git_reference *new_ref;
+
+	char ref_name[MAX_GITDIR_TREE_STRUCTURE_PATH_LENGTH];
+
+	int type_str_len, tag_name_len, tagger_str_len, message_len;
+	int error, should_update_ref = 0;
+
+	if ((error = tag_valid_in_odb(&new_ref, ref_name, target, target_type, repo, tag_name)) < GIT_SUCCESS)
+		return git__rethrow(error, "Failed to create tag");
+	
+	/** Ensure the tag name doesn't conflict with an already existing 
+	 *   reference unless overwriting has explictly been requested **/
+	if(new_ref != NULL) {
+		if(!allow_ref_overwrite) {
+			git_oid_cpy(oid, git_reference_oid(new_ref));
+			return git__throw(GIT_EEXISTS, "Tag already exists");
+		} else {
+			should_update_ref = 1;
+		}
+	}
+
 	type_str = git_object_type2string(target_type);
 
 	tagger_str_len = git_signature__write(&tagger_str, "tagger", tagger);
@@ -283,15 +307,44 @@ int git_tag_create_frombuffer(git_oid *oid, git_repository *repo, const char *bu
 {
 	git_tag tag;
 	int error;
+	git_odb_stream *stream;
+	
+	git_reference *new_ref;
+	char ref_name[MAX_GITDIR_TREE_STRUCTURE_PATH_LENGTH];
 	
 	assert(oid && buffer);
 	
 	memset(&tag, 0, sizeof(tag));
 	
+	/* validate the buffer */
+	
 	if ((error = parse_tag_buffer(&tag, buffer, buffer + strlen(buffer))) < GIT_SUCCESS)
 		return git__rethrow(error, "Failed to create tag");
 	
-	error = git_tag_create(oid, repo, tag.tag_name, &tag.target, tag.type, tag.tagger, tag.message);
+	if ((error = tag_valid_in_odb(&new_ref, ref_name, &tag.target, tag.type, repo, tag.tag_name)) < GIT_SUCCESS)
+		return git__rethrow(error, "Failed to create tag");
+	
+	if(new_ref != NULL) {
+		git_oid_cpy(oid, git_reference_oid(new_ref));
+		return git__throw(GIT_EEXISTS, "Tag already exists");
+	}
+	
+	
+	/* write the buffer */
+	
+	if ((error = git_odb_open_wstream(&stream, repo->db, strlen(buffer), GIT_OBJ_TAG)) < GIT_SUCCESS)
+		return git__rethrow(error, "Failed to create tag");
+	
+	stream->write(stream, buffer, strlen(buffer));
+	
+	error = stream->finalize_write(oid, stream);
+	stream->free(stream);
+	
+	if (error < GIT_SUCCESS)
+		return git__rethrow(error, "Failed to create tag");
+	
+	
+	error = git_reference_create_oid(&new_ref, repo, ref_name, oid);
 	
 	git_signature_free(tag.tagger);
 	free(tag.tag_name);