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import of dnsmasq-2.34.tar.gz

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This commit is contained in:
Simon Kelley
2006-10-16 20:04:18 +01:00
parent 208b65c5cf
commit 1697269ce7
33 changed files with 3660 additions and 2711 deletions
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127
src/forward.c
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@@ -14,7 +14,6 @@
static struct frec *frec_list = NULL;
static struct frec *get_new_frec(struct daemon *daemon, time_t now);
static struct frec *lookup_frec(unsigned short id);
static struct frec *lookup_frec_by_sender(unsigned short id,
union mysockaddr *addr,
@@ -232,7 +231,7 @@ static void forward_query(struct daemon *daemon, int udpfd, union mysockaddr *ud
if (gotname)
flags = search_servers(daemon, now, &addrp, gotname, daemon->namebuff, &type, &domain);
if (!flags && !(forward = get_new_frec(daemon, now)))
if (!flags && !(forward = get_new_frec(daemon, now, NULL)))
/* table full - server failure. */
flags = F_NEG;
@@ -459,7 +458,6 @@ void reply_query(struct serverfd *sfd, struct daemon *daemon, time_t now)
header->arcount = htons(0);
if ((nn = resize_packet(header, (size_t)n, pheader, plen)))
{
forward->forwardall = 1;
header->qr = 0;
header->tc = 0;
forward_query(daemon, -1, NULL, NULL, 0, header, nn, now, forward);
@@ -657,31 +655,6 @@ void receive_query(struct listener *listen, struct daemon *daemon, time_t now)
header, (size_t)n, now, NULL);
}
static int read_write(int fd, unsigned char *packet, int size, int rw)
{
ssize_t n, done;
for (done = 0; done < size; done += n)
{
retry:
if (rw)
n = read(fd, &packet[done], (size_t)(size - done));
else
n = write(fd, &packet[done], (size_t)(size - done));
if (n == 0)
return 0;
else if (n == -1)
{
if (errno == EINTR)
goto retry;
else
return 0;
}
}
return 1;
}
/* The daemon forks before calling this: it should deal with one connection,
blocking as neccessary, and then return. Note, need to be a bit careful
about resources for debug mode, when the fork is suppressed: that's
@@ -837,49 +810,10 @@ unsigned char *tcp_request(struct daemon *daemon, int confd, time_t now,
}
}
static struct frec *get_new_frec(struct daemon *daemon, time_t now)
static struct frec *allocate_frec(time_t now)
{
struct frec *f = frec_list, *oldest = NULL;
time_t oldtime = now;
int count = 0;
static time_t warntime = 0;
while (f)
{
if (f->new_id == 0)
{
f->time = now;
return f;
}
if (difftime(f->time, oldtime) <= 0)
{
oldtime = f->time;
oldest = f;
}
count++;
f = f->next;
}
struct frec *f;
/* can't find empty one, use oldest if there is one
and it's older than timeout */
if (oldest && difftime(now, oldtime) > TIMEOUT)
{
oldest->time = now;
return oldest;
}
if (count > daemon->ftabsize)
{ /* limit logging rate so syslog isn't DOSed either */
if (!warntime || difftime(now, warntime) > LOGRATE)
{
warntime = now;
syslog(LOG_WARNING, _("forwarding table overflow: check for server loops."));
}
return NULL;
}
if ((f = (struct frec *)malloc(sizeof(struct frec))))
{
f->next = frec_list;
@@ -887,6 +821,61 @@ static struct frec *get_new_frec(struct daemon *daemon, time_t now)
f->new_id = 0;
frec_list = f;
}
return f;
}
/* if wait==NULL return a free or older than TIMEOUT record.
else return *wait zero if one available, or *wait is delay to
when the oldest in-use record will expire. */
struct frec *get_new_frec(struct daemon *daemon, time_t now, int *wait)
{
struct frec *f, *oldest;
int count;
if (wait)
*wait = 0;
for (f = frec_list, oldest = NULL, count = 0; f; f = f->next, count++)
if (f->new_id == 0)
{
f->time = now;
return f;
}
else if (!oldest || difftime(f->time, oldest->time) <= 0)
oldest = f;
/* can't find empty one, use oldest if there is one
and it's older than timeout */
if (oldest && ((int)difftime(now, oldest->time)) >= TIMEOUT)
{
/* keep stuff for twice timeout if we can by allocating a new
record instead */
if (difftime(now, oldest->time) < 2*TIMEOUT &&
count <= daemon->ftabsize &&
(f = allocate_frec(now)))
return f;
if (!wait)
{
oldest->new_id = 0;
oldest->time = now;
}
return oldest;
}
/* none available, calculate time 'till oldest record expires */
if (count > daemon->ftabsize)
{
if (oldest && wait)
*wait = oldest->time + (time_t)TIMEOUT - now;
return NULL;
}
if (!(f = allocate_frec(now)) && wait)
/* wait one second on malloc failure */
*wait = 1;
return f; /* OK if malloc fails and this is NULL */
}