improve error handling in post-STORE UIDNEXT fallback

that's mostly hypothetical, but let's not make assumptions.

this also adds EXPUNGE response handling to make total_msgs reliable. in
principle, this affects the post-SELECT UIDNEXT fallback as well, but
there the racing window is so short that this barely improves anything.

amends 94022a67.
This commit is contained in:
Oswald Buddenhagen 2020-08-05 20:58:53 +02:00
parent 42f165ecf7
commit 23513564df

View File

@ -122,7 +122,7 @@ struct imap_store {
string_list_t *boxes; // _list results
char listed; // was _list already run with these flags?
// note that the message counts do _not_ reflect stats from msgs,
// but mailbox totals. also, don't trust them beyond the initial load.
// but mailbox totals.
int total_msgs, recent_msgs;
uint uidvalidity, uidnext;
message_t *msgs;
@ -1514,6 +1514,8 @@ imap_socket_read( void *aux )
} else if ((arg1 = next_arg( &cmd ))) {
if (!strcmp( "EXISTS", arg1 ))
ctx->total_msgs = atoi( arg );
else if (!strcmp( "EXPUNGE", arg1 ))
ctx->total_msgs--;
else if (!strcmp( "RECENT", arg1 ))
ctx->recent_msgs = atoi( arg );
else if(!strcmp ( "FETCH", arg1 )) {
@ -3157,10 +3159,18 @@ imap_find_new_msgs_p3( imap_store_t *ctx, imap_cmd_t *gcmd, int response )
imap_find_new_msgs_p4( ctx, gcmd, response );
return;
}
if (!ctx->uidnext) {
// We are assuming that the new messages were not in fact instantly deleted.
if (ctx->uidnext <= cmdp->uid) {
if (!ctx->uidnext && ctx->total_msgs) {
error( "IMAP error: re-querying server for highest UID failed\n" );
imap_find_new_msgs_p4( ctx, gcmd, RESP_NO );
} else {
// The messages evaporated, or the server just didn't register them -
// we'll catch that later (via lost TUIDs).
// This case is why we do the extra roundtrip instead of simply passing
// '*' as the end of the range below - IMAP ranges are unordered, so we
// would potentially re-fetch an already loaded message.
imap_find_new_msgs_p4( ctx, gcmd, RESP_OK );
}
return;
}
INIT_IMAP_CMD(imap_cmd_find_new_t, cmd, cmdp->callback, cmdp->callback_aux)