dsync: Fix hierarchical mailbox name parts individually

For example with filesystem-based mailbox formats it's not allowed to create
"box/../child" mailbox. With previous code dsync just gave up and created
the mailbox name based on its GUID. This is now improved to instead try to
insert '_' character after each hierarchy separator so the newly fixed
mailbox name is "box/_../child".

diff --git a/src/doveadm/dsync/dsync-brain-mailbox-tree.c b/src/doveadm/dsync/dsync-brain-mailbox-tree.c
index 0e520ae2f0acfd09a3f4522d9dab2121251947dc..3c05873d80a0c082288ac8ba1b2a863893266b51 100644 (file)
--- a/src/doveadm/dsync/dsync-brain-mailbox-tree.c
+++ b/src/doveadm/dsync/dsync-brain-mailbox-tree.c
@@ -218,12 +218,70 @@ dsync_is_valid_name(struct mail_namespace *ns, const char *vname)
        return ret;
 }
 
+static bool
+dsync_is_valid_name_until(struct mail_namespace *ns, string_t *vname_full,
+                         unsigned int end_pos)
+{
+       const char *vname;
+       if (end_pos == str_len(vname_full))
+               vname = str_c(vname_full);
+       else
+               vname = t_strndup(str_c(vname_full), end_pos);
+       return dsync_is_valid_name(ns, vname);
+}
+
+static bool
+dsync_fix_mailbox_name_until(struct mail_namespace *ns, string_t *vname_full,
+                            char alt_char, unsigned int start_pos,
+                            unsigned int *_end_pos)
+{
+       unsigned int end_pos = *_end_pos;
+       unsigned int i;
+
+       if (dsync_is_valid_name_until(ns, vname_full, end_pos))
+               return TRUE;
+
+       /* 1) change any real separators to alt separators (this
+          wouldn't be necessary with listescape, but don't bother
+          detecting it) */
+       char list_sep = mailbox_list_get_hierarchy_sep(ns->list);
+       char ns_sep = mail_namespace_get_sep(ns);
+       if (list_sep != ns_sep) {
+               char *v = str_c_modifiable(vname_full);
+               for (i = start_pos; i < end_pos; i++) {
+                       if (v[i] == list_sep)
+                               v[i] = alt_char;
+               }
+               if (dsync_is_valid_name_until(ns, vname_full, end_pos))
+                       return TRUE;
+       }
+
+       /* 2) '/' characters aren't valid without listescape */
+       if (ns_sep != '/' && list_sep != '/') {
+               char *v = str_c_modifiable(vname_full);
+               for (i = start_pos; i < end_pos; i++) {
+                       if (v[i] == '/')
+                               v[i] = alt_char;
+               }
+               if (dsync_is_valid_name_until(ns, vname_full, end_pos))
+                       return TRUE;
+       }
+
+       /* 3) probably some reserved name (e.g. dbox-Mails or ..) */
+       str_insert(vname_full, start_pos, "_"); end_pos++; *_end_pos += 1;
+       if (dsync_is_valid_name_until(ns, vname_full, end_pos))
+               return TRUE;
+
+       return FALSE;
+}
+
 static void
 dsync_fix_mailbox_name(struct mail_namespace *ns, string_t *vname_str,
                       char alt_char)
 {
        const char *old_vname;
-       char *vname, list_sep = mailbox_list_get_hierarchy_sep(ns->list);
+       char *vname;
+       char ns_sep = mail_namespace_get_sep(ns);
        guid_128_t guid;
        unsigned int i, start_pos;
 
@@ -250,36 +308,30 @@ dsync_fix_mailbox_name(struct mail_namespace *ns, string_t *vname_str,
        if (dsync_is_valid_name(ns, vname))
                return;
 
-       /* 1) change any real separators to alt separators (this wouldn't
-          be necessary with listescape, but don't bother detecting it) */
-       if (list_sep != mail_namespace_get_sep(ns)) {
-               for (i = start_pos; vname[i] != '\0'; i++) {
-                       if (vname[i] == list_sep)
-                               vname[i] = alt_char;
-               }
-               if (dsync_is_valid_name(ns, vname))
-                       return;
-       }
-       /* 2) '/' characters aren't valid without listescape */
-       if (mail_namespace_get_sep(ns) != '/' && list_sep != '/') {
-               for (i = start_pos; vname[i] != '\0'; i++) {
-                       if (vname[i] == '/')
-                               vname[i] = alt_char;
+       /* Check/fix each hierarchical name separately */
+       const char *p;
+       do {
+               i_assert(start_pos <= str_len(vname_str));
+               p = strchr(str_c(vname_str) + start_pos, ns_sep);
+               unsigned int end_pos;
+               if (p == NULL)
+                       end_pos = str_len(vname_str);
+               else
+                       end_pos = p - str_c(vname_str);
+
+               if (!dsync_fix_mailbox_name_until(ns, vname_str, alt_char,
+                                                 start_pos, &end_pos)) {
+                       /* Couldn't fix it. Name is too long? Just give up and
+                          generate a unique name. */
+                       guid_128_generate(guid);
+                       str_truncate(vname_str, 0);
+                       str_append(vname_str, ns->prefix);
+                       str_append(vname_str, guid_128_to_string(guid));
+                       i_assert(dsync_is_valid_name(ns, str_c(vname_str)));
+                       break;
                }
-               if (dsync_is_valid_name(ns, vname))
-                       return;
-       }
-       /* 3) probably some reserved name (e.g. dbox-Mails) */
-       str_insert(vname_str, ns->prefix_len, "_");
-       if (dsync_is_valid_name(ns, str_c(vname_str)))
-               return;
-
-       /* 4) name is too long? just give up and generate a unique name */
-       guid_128_generate(guid);
-       str_truncate(vname_str, 0);
-       str_append(vname_str, ns->prefix);
-       str_append(vname_str, guid_128_to_string(guid));
-       i_assert(dsync_is_valid_name(ns, str_c(vname_str)));
+               start_pos = end_pos + 1;
+       } while (p != NULL);
 }
 
 static int