From bc425b339b067bebe3d49907e63b0e81eb261bd2 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Sat, 15 Jan 2011 11:10:11 -0500 Subject: Signal temporary host lookup errors in nscd as such to the requester. --- nscd/hstcache.c | 27 +++++++++++++++++++++++---- 1 file changed, 23 insertions(+), 4 deletions(-) (limited to 'nscd') diff --git a/nscd/hstcache.c b/nscd/hstcache.c index 228f6fd..a6055cf 100644 --- a/nscd/hstcache.c +++ b/nscd/hstcache.c @@ -1,5 +1,5 @@ /* Cache handling for host lookup. - Copyright (C) 1998-2008, 2009 Free Software Foundation, Inc. + Copyright (C) 1998-2008, 2009, 2011 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper , 1998. @@ -77,6 +77,20 @@ static const hst_response_header notfound = }; +/* This is the standard reply in case there are temporary problems. */ +static const hst_response_header tryagain = +{ + .version = NSCD_VERSION, + .found = 0, + .h_name_len = 0, + .h_aliases_cnt = 0, + .h_addrtype = -1, + .h_length = -1, + .h_addr_list_cnt = 0, + .error = TRY_AGAIN +}; + + static void cache_addhst (struct database_dyn *db, int fd, request_header *req, const void *key, struct hostent *hst, uid_t owner, @@ -111,11 +125,15 @@ cache_addhst (struct database_dyn *db, int fd, request_header *req, else { /* We have no data. This means we send the standard reply for this - case. */ + case. Possibly this is only temporary. */ ssize_t total = sizeof (notfound); + assert (sizeof (notfound) == sizeof (tryagain)); + + const hst_response_header *resp = (errval == EAGAIN + ? &tryagain : ¬found); if (fd != -1 && - TEMP_FAILURE_RETRY (send (fd, ¬found, total, + TEMP_FAILURE_RETRY (send (fd, resp, total, MSG_NOSIGNAL)) != total) all_written = false; @@ -135,7 +153,7 @@ cache_addhst (struct database_dyn *db, int fd, request_header *req, ? db->negtimeout : ttl); /* This is the reply. */ - memcpy (&dataset->resp, ¬found, total); + memcpy (&dataset->resp, resp, total); /* Copy the key data. */ memcpy (dataset->strdata, key, req->key_len); @@ -490,6 +508,7 @@ addhstbyX (struct database_dyn *db, int fd, request_header *req, /* We set the error to indicate this is (possibly) a temporary error and that it does not mean the entry is not available at all. */ + h_errno = TRY_AGAIN; errval = EAGAIN; break; } -- cgit v1.1