Improve GIT_EUSER handling

This adds giterr_user_cancel to return GIT_EUSER and clear any
error message that is sitting around.  As a result of using that
in places, we need to be more thorough with capturing errors that
happen inside a callback when used internally.  To help with that,
this also adds giterr_capture and giterr_restore so that when we
internally use a foreach-type function that clears errors and
converts them to GIT_EUSER, it is easier to restore not just the
return value, but the actual error message text.

1 files changed, 24 insertions, 8 deletions

diff --git a/src/status.c b/src/status.c
index 07fdcb5c3..fb99fb4e4 100644
--- a/src/status.c
+++ b/src/status.c
@@ -152,25 +152,32 @@ static git_status_t status_compute(
 	return st;
 }
 
+struct status_data {
+	git_status_list *status;
+	git_error_state err;
+};
+
 static int status_collect(
 	git_diff_delta *head2idx,
 	git_diff_delta *idx2wd,
 	void *payload)
 {
-	git_status_list *status = payload;
+	struct status_data *data = payload;
 	git_status_entry *status_entry;
 
-	if (!status_is_included(status, head2idx, idx2wd))
+	if (!status_is_included(data->status, head2idx, idx2wd))
 		return 0;
 
 	status_entry = git__malloc(sizeof(git_status_entry));
-	GITERR_CHECK_ALLOC(status_entry);
+	if (!status_entry)
+		return giterr_capture(&data->err, -1);
 
-	status_entry->status = status_compute(status, head2idx, idx2wd);
+	status_entry->status = status_compute(data->status, head2idx, idx2wd);
 	status_entry->head_to_index = head2idx;
 	status_entry->index_to_workdir = idx2wd;
 
-	return git_vector_insert(&status->paired, status_entry);
+	return giterr_capture(
+		&data->err, git_vector_insert(&data->status->paired, status_entry));
 }
 
 GIT_INLINE(int) status_entry_cmp_base(
@@ -314,9 +321,18 @@ int git_status_list_new(
 			goto done;
 	}
 
-	if ((error = git_diff__paired_foreach(
-			status->head2idx, status->idx2wd, status_collect, status)) < 0)
-		goto done;
+	{
+		struct status_data data = { 0 };
+		data.status = status;
+
+		error = git_diff__paired_foreach(
+			status->head2idx, status->idx2wd, status_collect, &data);
+
+		if (error == GIT_EUSER)
+			error = giterr_restore(&data.err);
+		if (error < 0)
+			goto done;
+	}
 
 	if (flags & GIT_STATUS_OPT_SORT_CASE_SENSITIVELY)
 		git_vector_set_cmp(&status->paired, status_entry_cmp);