builtin-checkout.c: check error return from read_cache()

diff --git a/refs.c b/refs.c
index 293389e7641a8d4ec948f21407de3f69eacbdddd..33ced65a7801f8653d608a9580e237ce8df39ae2 100644 (file)
--- a/refs.c
+++ b/refs.c
@@ -390,6 +390,18 @@ int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *re
        return retval;
 }
 
+/*
+ * If the "reading" argument is set, this function finds out what _object_
+ * the ref points at by "reading" the ref.  The ref, if it is not symbolic,
+ * has to exist, and if it is symbolic, it has to point at an existing ref,
+ * because the "read" goes through the symref to the ref it points at.
+ *
+ * The access that is not "reading" may often be "writing", but does not
+ * have to; it can be merely checking _where it leads to_. If it is a
+ * prelude to "writing" to the ref, a write to a symref that points at
+ * yet-to-be-born ref will create the real ref pointed by the symref.
+ * reading=0 allows the caller to check where such a symref leads to.
+ */
 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
 {
        int depth = MAXDEPTH;
@@ -410,13 +422,7 @@ const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *
                        return NULL;
 
                git_snpath(path, sizeof(path), "%s", ref);
-               /* Special case: non-existing file.
-                * Not having the refs/heads/new-branch is OK
-                * if we are writing into it, so is .git/HEAD
-                * that points at refs/heads/master still to be
-                * born.  It is NOT OK if we are resolving for
-                * reading.
-                */
+               /* Special case: non-existing file. */
                if (lstat(path, &st) < 0) {
                        struct ref_list *list = get_packed_refs();
                        while (list) {
@@ -934,7 +940,7 @@ int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
                        lock->lk->filename[i] = 0;
                        path = lock->lk->filename;
                } else {
-                       path = git_path(refname);
+                       path = git_path("%s", refname);
                }
                err = unlink(path);
                if (err && errno != ENOENT) {