files: new dup_fdinfo() and dup_fle() helpers introduced

This helpers will be used by autofs restore to create temporary pipe
descriptors.
Signed-off-by: Stanislav Kinsburskiy <skinsbursky@virtuozzo.com>
Signed-off-by: Pavel Emelyanov <xemul@virtuozzo.com>

criu/files.c

@@ -661,6 +661,35 @@ static int collect_fd(int pid, FdinfoEntry *e, struct rst_info *rst_info)
 	return 0;
 }
 
+FdinfoEntry *dup_fdinfo(FdinfoEntry *old, int fd, unsigned flags)
+{
+	FdinfoEntry *e;
+
+	e = shmalloc(sizeof(*e));
+	if (!e)
+		return NULL;
+
+	fdinfo_entry__init(e);
+
+	e->id		= old->id;
+	e->type		= old->type;
+	e->fd		= fd;
+	e->flags	= flags;
+	return e;
+}
+
+int dup_fle(struct pstree_item *task, struct fdinfo_list_entry *ple,
+		   int fd, unsigned flags)
+{
+	FdinfoEntry *e;
+
+	e = dup_fdinfo(ple->fe, fd, flags);
+	if (!e)
+		return -1;
+
+	return collect_fd(task->pid.virt, e, rsti(task));
+}
+
 int prepare_ctl_tty(int pid, struct rst_info *rst_info, u32 ctl_tty_id)
 {
 	FdinfoEntry *e;

criu/include/files.h

@@ -212,4 +212,8 @@ extern char *external_lookup_by_key(char *id);
 
 extern bool inherited_fd(struct file_desc *, int *fdp);
 
+extern FdinfoEntry *dup_fdinfo(FdinfoEntry *old, int fd, unsigned flags);
+int dup_fle(struct pstree_item *task, struct fdinfo_list_entry *ple,
+	    int fd, unsigned flags);
+
 #endif /* __CR_FILES_H__ */