[ghex] direct: Error on attempts to save to a path other than originating

[Logan Rathbone <larathbone src gnome org>]

commit 434d4f92a4768d9b5f57c8b4c74258d9b2012fbd
Author: Logan Rathbone <poprocks gmail com>
Date:   Thu Jun 16 15:08:40 2022 -0400

    direct: Error on attempts to save to a path other than originating

 src/hex-buffer-direct.c | 10 ++++++++++
 1 file changed, 10 insertions(+)
---
diff --git a/src/hex-buffer-direct.c b/src/hex-buffer-direct.c
index 6fa8f3b..e5d6aff 100644
--- a/src/hex-buffer-direct.c
+++ b/src/hex-buffer-direct.c
@@ -62,6 +62,7 @@ struct _HexBufferDirect
        GError *error;          /* no custom codes; use codes from errno */
        int last_errno;         /* cache in case we need to re-report errno error. */
 
+       char *path;
        int fd;                         /* file descriptor for direct read/write */
        gint64 payload;         /* size of the payload */
 
@@ -272,6 +273,7 @@ hex_buffer_direct_finalize (GObject *gobject)
        {
                close (self->fd);
        }
+       g_free (self->path);
 
        /* chain up */
        G_OBJECT_CLASS(hex_buffer_direct_parent_class)->finalize (gobject);
@@ -374,6 +376,7 @@ hex_buffer_direct_set_file (HexBuffer *buf, GFile *file)
        }
 
        self->file = file;
+       self->path = g_strdup (file_path);
        g_object_notify (G_OBJECT(self), "file");
        return TRUE;
 }
@@ -518,6 +521,13 @@ hex_buffer_direct_write_to_file (HexBuffer *buf,
        g_return_val_if_fail (self->fd != -1, FALSE);
        g_return_val_if_fail (G_IS_FILE (file), FALSE);
 
+       if (g_strcmp0 (self->path, g_file_peek_path (file)) != 0)
+       {
+               set_error (self, _("With direct-write mode, you cannot save a file "
+                                       "to a path other than its originating path"));
+               return FALSE;
+       }
+
        keys = (gint64 **)g_hash_table_get_keys_as_array (self->changes, &len);
 
        /* FIXME - very inefficient - we should at least implement a sorter