Add filter options and ALLOW_UNSAFE

Diff and status do not want core.safecrlf to actually raise an
error regardless of the setting, so this extends the filter API
with an additional options flags parameter and adds a flag so that
filters can be applied with GIT_FILTER_OPT_ALLOW_UNSAFE, indicating
that unsafe filter application should be downgraded from a failure
to a warning.

1 files changed, 19 insertions, 4 deletions

diff --git a/src/crlf.c b/src/crlf.c
index 8be1b9a05..dad3ecebc 100644
--- a/src/crlf.c
+++ b/src/crlf.c
@@ -139,10 +139,19 @@ static int crlf_apply_to_odb(
 			return GIT_PASSTHROUGH;
 
 		/* If safecrlf is enabled, sanity-check the result. */
-		if (ca->safe_crlf && (stats.cr != stats.crlf || stats.lf != stats.crlf)) {
-			giterr_set(GITERR_FILTER, "LF would be replaced by CRLF in '%s'",
-				git_filter_source_path(src));
-			return -1;
+		if (stats.cr != stats.crlf || stats.lf != stats.crlf) {
+			switch (ca->safe_crlf) {
+			case GIT_SAFE_CRLF_FAIL:
+				giterr_set(
+					GITERR_FILTER, "LF would be replaced by CRLF in '%s'",
+					git_filter_source_path(src));
+				return -1;
+			case GIT_SAFE_CRLF_WARN:
+				/* TODO: issue warning when warning API is available */;
+				break;
+			default:
+				break;
+			}
 		}
 
 		/*
@@ -267,6 +276,7 @@ static int crlf_check(
 	if (ca.crlf_action == GIT_CRLF_GUESS ||
 		(ca.crlf_action == GIT_CRLF_AUTO &&
 		git_filter_source_mode(src) == GIT_FILTER_SMUDGE)) {
+
 		error = git_repository__cvar(
 			&ca.auto_crlf, git_filter_source_repo(src), GIT_CVAR_AUTO_CRLF);
 		if (error < 0)
@@ -285,6 +295,11 @@ static int crlf_check(
 			&ca.safe_crlf, git_filter_source_repo(src), GIT_CVAR_SAFE_CRLF);
 		if (error < 0)
 			return error;
+
+		/* downgrade FAIL to WARN if ALLOW_UNSAFE option is used */
+		if ((git_filter_source_options(src) & GIT_FILTER_OPT_ALLOW_UNSAFE) &&
+			ca.safe_crlf == GIT_SAFE_CRLF_FAIL)
+			ca.safe_crlf = GIT_SAFE_CRLF_WARN;
 	}
 
 	*payload = git__malloc(sizeof(ca));