imapc: Fix prefetching specific headers

FETCH BODY[HEADER.FIELDS ...] shouldn't be used if imapc_features doesn't
include fetch-headers. Also neither this nor BODY[HEADER] should be sent
if we already have header/body stream.

diff --git a/src/lib-storage/index/imapc/imapc-mail-fetch.c b/src/lib-storage/index/imapc/imapc-mail-fetch.c
index 4ca4e09ce447c308e4a5b0a65715d70cc27181ae..8651483615fbcdbc80f02851b3d308fb1f8dad15 100644 (file)
--- a/src/lib-storage/index/imapc/imapc-mail-fetch.c
+++ b/src/lib-storage/index/imapc/imapc-mail-fetch.c
@@ -213,6 +213,9 @@ imapc_mail_send_fetch(struct mail *_mail, enum mail_fetch_field fields,
        uint32_t seq;
        unsigned int i;
 
+       i_assert(headers == NULL ||
+                IMAPC_BOX_HAS_FEATURE(mbox, IMAPC_FEATURE_FETCH_HEADERS));
+
        if (_mail->lookup_abort != MAIL_LOOKUP_ABORT_NEVER) {
                mail_set_aborted(_mail);
                return -1;
@@ -371,6 +374,7 @@ bool imapc_mail_prefetch(struct mail *_mail)
        struct imapc_mailbox *mbox = (struct imapc_mailbox *)_mail->box;
        struct index_mail_data *data = &mail->imail.data;
        enum mail_fetch_field fields;
+       const char *const *headers = NULL;
 
        if (mbox->prev_mail_cache.uid == _mail->uid)
                imapc_mail_cache_get(mail, &mbox->prev_mail_cache);
@@ -378,12 +382,17 @@ bool imapc_mail_prefetch(struct mail *_mail)
        imapc_mail_update_access_parts(&mail->imail);
 
        fields = imapc_mail_get_wanted_fetch_fields(mail);
-       if (fields != 0 ||
-           (data->wanted_headers != NULL &&
-            !imapc_mail_has_headers_in_cache(&mail->imail, data->wanted_headers))) T_BEGIN {
-               if (imapc_mail_send_fetch(_mail, fields,
-                                         data->wanted_headers == NULL ? NULL :
-                                         data->wanted_headers->name) > 0)
+       if (data->wanted_headers != NULL && data->stream == NULL &&
+           (fields & MAIL_FETCH_STREAM_HEADER) == 0 &&
+           !imapc_mail_has_headers_in_cache(&mail->imail, data->wanted_headers)) {
+               /* fetch specific headers */
+               if (IMAPC_BOX_HAS_FEATURE(mbox, IMAPC_FEATURE_FETCH_HEADERS))
+                       headers = data->wanted_headers->name;
+               else
+                       fields |= MAIL_FETCH_STREAM_HEADER;
+       }
+       if (fields != 0 || headers != NULL) T_BEGIN {
+               if (imapc_mail_send_fetch(_mail, fields, headers) > 0)
                        mail->imail.data.prefetch_sent = TRUE;
        } T_END;
        return !mail->imail.data.prefetch_sent;