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Yeah – this really should be implemented as Rohan suggested – by
loading the hosts file into the RR cache (and re-reading if a cache flush is
invoked). Sounds like this is a problem to tackle another day. : ) From: resiprocate-devel-bounces@xxxxxxxxxxxxxxxxxxx
[mailto:resiprocate-devel-bounces@xxxxxxxxxxxxxxxxxxx] On Behalf Of Robert
Sparks (trimming the discussion back to just the list - the
"also copy" was getting out of control) There is (very poor) code in ares to read /etc/hosts. There is (broken) code in ares to configure ares to use
/etc/hosts first then fail over to being a DNS client Off and on, a little over a year ago, we had a round of
patches that tried to keep ares from failing to /etc/hosts when it didn't find a record working as a DNS client
(because the very poor code mentioned above can be murderously slow). I don't remember whether we ended up with
a default where we look in DNS then in the hosts file, or a default where we look in DNS and then stop. It's clear from this conversation that we don't have a good
collective picture of what this particular subsystem is doing. We need to look at the tests carefully and make
sure they are meaningful, and we should put some real effort into documenting how to configure it, and
what the user should expect to have happen. RjS ps. Just to put it down somewhere again, what "very
poor" means is that for every lookup, ares will open the hosts file, scan/parse each row, doing string
comparisons for what you're looking for. Here's the code: static int file_lookup(const char *name, struct hostent
**host) { FILE *fp; char **alias; int status; #ifdef WIN32 fp = fopen(w32hostspath, "r"); #else fp = fopen(PATH_HOSTS, "r"); #endif if (!fp) return ARES_ENOTFOUND; while ((status = ares__get_hostent(fp, host)) ==
ARES_SUCCESS) { if (strcasecmp((*host)->h_name,
name) == 0) break; for (alias = (*host)->h_aliases;
*alias; alias++) { if (strcasecmp(*alias,
name) == 0) break; } if (*alias) break; ares_free_hostent(*host); } fclose(fp); if (status == ARES_EOF) status = ARES_ENOTFOUND; if (status != ARES_SUCCESS) *host = NULL; return status; } On Aug 14, 2006, at 7:31 PM, Scott Godin wrote:
Ares does have support for reading the local hosts file, and it
did used to work before the DNS caching stuff was added. A list member
has already noted this and has posted a fix that re-enables the host file
lookup, but I haven’t had a chance to examine it closely. From: Rohan Mahy [mailto:rohan.mahy@xxxxxxxxxxxxxxx]
Hi,
Not tested - I looked at code (this is all in ares) and on windows
it uses the registry to find the path - this probably needs be
tested separately on each OS and on each major version of
windows.
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