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code police: fix indents, < 80 columns, reflowed comments

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pull/9/head
Daniel Stenberg 13 years ago
parent 8283fb15e6
commit e447bc5c60
1 changed files with 73 additions and 78 deletions
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  1. 151
      ares_process.c

151
ares_process.c
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@ -268,7 +268,7 @@ static void write_tcp_data(ares_channel channel,
if (wcount < 0) if (wcount < 0)
{ {
if (!try_again(SOCKERRNO)) if (!try_again(SOCKERRNO))
handle_error(channel, i, now); handle_error(channel, i, now);
continue; continue;
} }
@ -284,7 +284,7 @@ static void write_tcp_data(ares_channel channel,
if (scount < 0) if (scount < 0)
{ {
if (!try_again(SOCKERRNO)) if (!try_again(SOCKERRNO))
handle_error(channel, i, now); handle_error(channel, i, now);
continue; continue;
} }
@ -356,11 +356,11 @@ static void read_tcp_data(ares_channel channel, fd_set *read_fds,
} }
if(read_fds) if(read_fds)
/* If there's an error and we close this socket, then open /* If there's an error and we close this socket, then open another
* another with the same fd to talk to another server, then we * with the same fd to talk to another server, then we don't want to
* don't want to think that it was the new socket that was * think that it was the new socket that was ready. This is not
* ready. This is not disastrous, but is likely to result in * disastrous, but is likely to result in extra system calls and
* extra system calls and confusion. */ * confusion. */
FD_CLR(server->tcp_socket, read_fds); FD_CLR(server->tcp_socket, read_fds);
if (server->tcp_lenbuf_pos != 2) if (server->tcp_lenbuf_pos != 2)
@ -374,7 +374,7 @@ static void read_tcp_data(ares_channel channel, fd_set *read_fds,
if (count <= 0) if (count <= 0)
{ {
if (!(count == -1 && try_again(SOCKERRNO))) if (!(count == -1 && try_again(SOCKERRNO)))
handle_error(channel, i, now); handle_error(channel, i, now);
continue; continue;
} }
@ -401,7 +401,7 @@ static void read_tcp_data(ares_channel channel, fd_set *read_fds,
if (count <= 0) if (count <= 0)
{ {
if (!(count == -1 && try_again(SOCKERRNO))) if (!(count == -1 && try_again(SOCKERRNO)))
handle_error(channel, i, now); handle_error(channel, i, now);
continue; continue;
} }
@ -481,8 +481,8 @@ static void read_udp_packets(ares_channel channel, fd_set *read_fds,
fromlen = sizeof(from.sa4); fromlen = sizeof(from.sa4);
else else
fromlen = sizeof(from.sa6); fromlen = sizeof(from.sa6);
count = (ssize_t)recvfrom(server->udp_socket, (void *)buf, sizeof(buf), count = (ssize_t)recvfrom(server->udp_socket, (void *)buf,
0, &from.sa, &fromlen); sizeof(buf), 0, &from.sa, &fromlen);
#else #else
count = sread(server->udp_socket, buf, sizeof(buf)); count = sread(server->udp_socket, buf, sizeof(buf));
#endif #endif
@ -494,9 +494,9 @@ static void read_udp_packets(ares_channel channel, fd_set *read_fds,
handle_error(channel, i, now); handle_error(channel, i, now);
#ifdef HAVE_RECVFROM #ifdef HAVE_RECVFROM
else if (!same_address(&from.sa, &server->addr)) else if (!same_address(&from.sa, &server->addr))
/* The address the response comes from does not match /* The address the response comes from does not match the address we
* the address we sent the request to. Someone may be * sent the request to. Someone may be attempting to perform a cache
* attempting to perform a cache poisoning attack. */ * poisoning attack. */
break; break;
#endif #endif
else else
@ -513,11 +513,10 @@ static void process_timeouts(ares_channel channel, struct timeval *now)
struct list_node* list_head; struct list_node* list_head;
struct list_node* list_node; struct list_node* list_node;
/* Process all the timeouts that have fired since the last time we /* Process all the timeouts that have fired since the last time we processed
* processed timeouts. If things are going well, then we'll have * timeouts. If things are going well, then we'll have hundreds/thousands of
* hundreds/thousands of queries that fall into future buckets, and * queries that fall into future buckets, and only a handful of requests
* only a handful of requests that fall into the "now" bucket, so * that fall into the "now" bucket, so this should be quite quick.
* this should be quite quick.
*/ */
for (t = channel->last_timeout_processed; t <= now->tv_sec; t++) for (t = channel->last_timeout_processed; t <= now->tv_sec; t++)
{ {
@ -559,11 +558,10 @@ static void process_answer(ares_channel channel, unsigned char *abuf,
rcode = DNS_HEADER_RCODE(abuf); rcode = DNS_HEADER_RCODE(abuf);
/* Find the query corresponding to this packet. The queries are /* Find the query corresponding to this packet. The queries are
* hashed/bucketed by query id, so this lookup should be quick. * hashed/bucketed by query id, so this lookup should be quick. Note that
* Note that both the query id and the questions must be the same; * both the query id and the questions must be the same; when the query id
* when the query id wraps around we can have multiple outstanding * wraps around we can have multiple outstanding queries with the same query
* queries with the same query id, so we need to check both the id and * id, so we need to check both the id and question.
* question.
*/ */
query = NULL; query = NULL;
list_head = &(channel->queries_by_qid[id % ARES_QID_TABLE_SIZE]); list_head = &(channel->queries_by_qid[id % ARES_QID_TABLE_SIZE]);
@ -645,12 +643,11 @@ static void handle_error(ares_channel channel, int whichserver,
/* Reset communications with this server. */ /* Reset communications with this server. */
ares__close_sockets(channel, server); ares__close_sockets(channel, server);
/* Tell all queries talking to this server to move on and not try /* Tell all queries talking to this server to move on and not try this
* this server again. We steal the current list of queries that were * server again. We steal the current list of queries that were in-flight to
* in-flight to this server, since when we call next_server this can * this server, since when we call next_server this can cause the queries to
* cause the queries to be re-sent to this server, which will * be re-sent to this server, which will re-insert these queries in that
* re-insert these queries in that same server->queries_to_server * same server->queries_to_server list.
* list.
*/ */
ares__init_list_head(&list_head); ares__init_list_head(&list_head);
ares__swap_lists(&list_head, &(server->queries_to_server)); ares__swap_lists(&list_head, &(server->queries_to_server));
@ -669,14 +666,15 @@ static void handle_error(ares_channel channel, int whichserver,
} }
static void skip_server(ares_channel channel, struct query *query, static void skip_server(ares_channel channel, struct query *query,
int whichserver) { int whichserver)
/* The given server gave us problems with this query, so if we have {
* the luxury of using other servers, then let's skip the /* The given server gave us problems with this query, so if we have the
* potentially broken server and just use the others. If we only * luxury of using other servers, then let's skip the potentially broken
* have one server and we need to retry then we should just go ahead * server and just use the others. If we only have one server and we need to
* and re-use that server, since it's our only hope; perhaps we * retry then we should just go ahead and re-use that server, since it's our
* just got unlucky, and retrying will work (eg, the server timed * only hope; perhaps we just got unlucky, and retrying will work (eg, the
* out our TCP connection just as we were sending another request). * server timed out our TCP connection just as we were sending another
* request).
*/ */
if (channel->nservers > 1) if (channel->nservers > 1)
{ {
@ -699,11 +697,10 @@ static void next_server(ares_channel channel, struct query *query,
query->server = (query->server + 1) % channel->nservers; query->server = (query->server + 1) % channel->nservers;
server = &channel->servers[query->server]; server = &channel->servers[query->server];
/* We don't want to use this server if (1) we decided this /* We don't want to use this server if (1) we decided this connection is
* connection is broken, and thus about to be closed, (2) * broken, and thus about to be closed, (2) we've decided to skip this
* we've decided to skip this server because of earlier * server because of earlier errors we encountered, or (3) we already
* errors we encountered, or (3) we already sent this query * sent this query over this exact connection.
* over this exact connection.
*/ */
if (!server->is_broken && if (!server->is_broken &&
!query->server_info[query->server].skip_server && !query->server_info[query->server].skip_server &&
@ -715,11 +712,11 @@ static void next_server(ares_channel channel, struct query *query,
return; return;
} }
/* You might think that with TCP we only need one try. However, /* You might think that with TCP we only need one try. However, even
* even when using TCP, servers can time-out our connection just * when using TCP, servers can time-out our connection just as we're
* as we're sending a request, or close our connection because * sending a request, or close our connection because they die, or never
* they die, or never send us a reply because they get wedged or * send us a reply because they get wedged or tickle a bug that drops
* tickle a bug that drops our request. * our request.
*/ */
} }
@ -755,11 +752,11 @@ void ares__send_query(ares_channel channel, struct query *query,
end_query(channel, query, ARES_ENOMEM, NULL, 0); end_query(channel, query, ARES_ENOMEM, NULL, 0);
return; return;
} }
/* To make the common case fast, we avoid copies by using the /* To make the common case fast, we avoid copies by using the query's
* query's tcpbuf for as long as the query is alive. In the rare * tcpbuf for as long as the query is alive. In the rare case where the
* case where the query ends while it's queued for transmission, * query ends while it's queued for transmission, then we give the
* then we give the sendreq its own copy of the request packet * sendreq its own copy of the request packet and put it in
* and put it in sendreq->data_storage. * sendreq->data_storage.
*/ */
sendreq->data_storage = NULL; sendreq->data_storage = NULL;
sendreq->data = query->tcpbuf; sendreq->data = query->tcpbuf;
@ -922,10 +919,12 @@ static int configure_socket(ares_socket_t s, int family, ares_channel channel)
} }
} }
else if (family == AF_INET6) { else if (family == AF_INET6) {
if (memcmp(channel->local_ip6, &ares_in6addr_any, sizeof(channel->local_ip6)) != 0) { if (memcmp(channel->local_ip6, &ares_in6addr_any,
sizeof(channel->local_ip6)) != 0) {
memset(&local.sa6, 0, sizeof(local.sa6)); memset(&local.sa6, 0, sizeof(local.sa6));
local.sa6.sin6_family = AF_INET6; local.sa6.sin6_family = AF_INET6;
memcpy(&local.sa6.sin6_addr, channel->local_ip6, sizeof(channel->local_ip6)); memcpy(&local.sa6.sin6_addr, channel->local_ip6,
sizeof(channel->local_ip6));
if (bind(s, &local.sa, sizeof(local.sa6)) < 0) if (bind(s, &local.sa, sizeof(local.sa6)) < 0)
return -1; return -1;
} }
@ -1228,19 +1227,17 @@ static void end_query (ares_channel channel, struct query *query, int status,
assert(sendreq->data_storage == NULL); assert(sendreq->data_storage == NULL);
if (status == ARES_SUCCESS) if (status == ARES_SUCCESS)
{ {
/* We got a reply for this query, but this queued /* We got a reply for this query, but this queued sendreq
* sendreq points into this soon-to-be-gone query's * points into this soon-to-be-gone query's tcpbuf. Probably
* tcpbuf. Probably this means we timed out and queued * this means we timed out and queued the query for
* the query for retransmission, then received a * retransmission, then received a response before actually
* response before actually retransmitting. This is * retransmitting. This is perfectly fine, so we want to keep
* perfectly fine, so we want to keep the connection * the connection running smoothly if we can. But in the worst
* running smoothly if we can. But in the worst case * case we may have sent only some prefix of the query, with
* we may have sent only some prefix of the query, * some suffix of the query left to send. Also, the buffer may
* with some suffix of the query left to send. Also, * be queued on multiple queues. To prevent dangling pointers
* the buffer may be queued on multiple queues. To * to the query's tcpbuf and handle these cases, we just give
* prevent dangling pointers to the query's tcpbuf and * such sendreqs their own copy of the query packet.
* handle these cases, we just give such sendreqs
* their own copy of the query packet.
*/ */
sendreq->data_storage = malloc(sendreq->len); sendreq->data_storage = malloc(sendreq->len);
if (sendreq->data_storage != NULL) if (sendreq->data_storage != NULL)
@ -1251,14 +1248,12 @@ static void end_query (ares_channel channel, struct query *query, int status,
} }
if ((status != ARES_SUCCESS) || (sendreq->data_storage == NULL)) if ((status != ARES_SUCCESS) || (sendreq->data_storage == NULL))
{ {
/* We encountered an error (probably a timeout, /* We encountered an error (probably a timeout, suggesting the
* suggesting the DNS server we're talking to is * DNS server we're talking to is probably unreachable,
* probably unreachable, wedged, or severely * wedged, or severely overloaded) or we couldn't copy the
* overloaded) or we couldn't copy the request, so * request, so mark the connection as broken. When we get to
* mark the connection as broken. When we get to * process_broken_connections() we'll close the connection and
* process_broken_connections() we'll close the * try to re-send requests to another server.
* connection and try to re-send requests to another
* server.
*/ */
server->is_broken = 1; server->is_broken = 1;
/* Just to be paranoid, zero out this sendreq... */ /* Just to be paranoid, zero out this sendreq... */
@ -1272,8 +1267,8 @@ static void end_query (ares_channel channel, struct query *query, int status,
query->callback(query->arg, status, query->timeouts, abuf, alen); query->callback(query->arg, status, query->timeouts, abuf, alen);
ares__free_query(query); ares__free_query(query);
/* Simple cleanup policy: if no queries are remaining, close all /* Simple cleanup policy: if no queries are remaining, close all network
* network sockets unless STAYOPEN is set. * sockets unless STAYOPEN is set.
*/ */
if (!(channel->flags & ARES_FLAG_STAYOPEN) && if (!(channel->flags & ARES_FLAG_STAYOPEN) &&
ares__is_list_empty(&(channel->all_queries))) ares__is_list_empty(&(channel->all_queries)))

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