static void
core_close(struct context *ctx, struct conn *conn)
{
rstatus_t status;
char type, *addrstr;
ASSERT(conn->sd > 0);
if (conn->client) {
type = 'c';
addrstr = nc_unresolve_peer_desc(conn->sd);
} else {
type = conn->proxy ? 'p' : 's';
addrstr = nc_unresolve_addr(conn->addr, conn->addrlen);
}
log_debug(LOG_NOTICE, "close %c %d '%s' on event %04"PRIX32" eof %d done "
"%d rb %zu sb %zu%c %s", type, conn->sd, addrstr, conn->events,
conn->eof, conn->done, conn->recv_bytes, conn->send_bytes,
conn->err ? ':' : ' ', conn->err ? strerror(conn->err) : "");
status = event_del_conn(ctx->ep, conn);
if (status < 0) {
log_warn("event del conn e %d %c %d failed, ignored: %s", ctx->ep,
type, conn->sd, strerror(errno));
}
conn->close(ctx, conn);
}
static void
req_log(struct msg *req)
{
struct msg *rsp; /* peer message (response) */
int64_t req_time; /* time cost for this request */
char *peer_str; /* peer client ip:port */
uint32_t req_len, rsp_len; /* request and response length */
struct string *req_type; /* request type string */
if (log_loggable(LOG_NOTICE) == 0) {
return;
}
/* a fragment? */
if (req->frag_id != 0 && req->frag_owner != req) {
return;
}
/* conn close normally? */
if (req->mlen == 0) {
return;
}
req_time = nc_usec_now() - req->start_ts;
rsp = req->peer;
req_len = req->mlen;
rsp_len = (rsp != NULL) ? rsp->mlen : 0;
if (req->key_end) {
req->key_end[0] = '\0';
}
/*
* FIXME: add backend addr here
* Maybe we can store addrstr just like server_pool in conn struct
* when connections are resolved
*/
peer_str = nc_unresolve_peer_desc(req->owner->sd);
req_type = msg_type_string(req->type);
log_debug(LOG_NOTICE, "req %"PRIu64" done on c %d req_time %"PRIi64".%03"PRIi64
" msec type %.*s narg %"PRIu32" req_len %"PRIu32" rsp_len %"PRIu32
" key0 '%s' peer '%s' done %d error %d",
req->id, req->owner->sd, req_time / 1000, req_time % 1000,
req_type->len, req_type->data, req->narg, req_len, rsp_len,
req->key_start, peer_str, req->done, req->error);
}
static void
req_log(struct msg *req)
{
struct msg *rsp; /* peer message (response) */
int64_t req_time; /* time cost for this request */
char *peer_str; /* peer client ip:port */
uint32_t req_len, rsp_len; /* request and response length */
struct string *req_type; /* request type string */
struct keypos *kpos;
if (log_loggable(LOG_NOTICE) == 0) {
return;
}
/* a fake request? */
if (req->owner == NULL) {
return;
}
/* a fragment? */
if (req->frag_id != 0 && req->frag_owner != req) {
return;
}
/* conn close normally? */
if (req->mlen == 0) {
return;
}
/*
* there is a race scenario where a requests comes in, the log level is not LOG_NOTICE,
* and before the response arrives you modify the log level to LOG_NOTICE
* using SIGTTIN OR SIGTTOU, then req_log() wouldn't have msg->start_ts set
*/
if (req->start_ts == 0) {
return;
}
req_time = nc_usec_now() - req->start_ts;
rsp = req->peer;
req_len = req->mlen;
rsp_len = (rsp != NULL) ? rsp->mlen : 0;
if (array_n(req->keys) < 1) {
return;
}
kpos = array_get(req->keys, 0);
if (kpos->end != NULL) {
*(kpos->end) = '\0';
}
/*
* FIXME: add backend addr here
* Maybe we can store addrstr just like server_pool in conn struct
* when connections are resolved
*/
peer_str = nc_unresolve_peer_desc(req->owner->sd);
req_type = msg_type_string(req->type);
log_debug(LOG_NOTICE, "req %"PRIu64" done on c %d req_time %"PRIi64".%03"PRIi64
" msec type %.*s narg %"PRIu32" req_len %"PRIu32" rsp_len %"PRIu32
" key0 '%s' peer '%s' done %d error %d",
req->id, req->owner->sd, req_time / 1000, req_time % 1000,
req_type->len, req_type->data, req->narg, req_len, rsp_len,
kpos->start, peer_str, req->done, req->error);
}
static rstatus_t
proxy_accept(struct context *ctx, struct conn *p)
{
rstatus_t status;
struct conn *c;
int sd;
ASSERT(p->proxy && !p->client);
ASSERT(p->sd > 0);
ASSERT(p->recv_active && p->recv_ready);
for (;;) {
sd = accept(p->sd, NULL, NULL);
if (sd < 0) {
if (errno == EINTR) {
log_debug(LOG_VERB, "accept on p %d not ready - eintr", p->sd);
continue;
}
if (errno == EAGAIN || errno == EWOULDBLOCK) {
log_debug(LOG_VERB, "accept on p %d not ready - eagain", p->sd);
p->recv_ready = 0;
return NC_OK;
}
/*
* FIXME: On EMFILE or ENFILE mask out IN event on the proxy; mask
* it back in when some existing connection gets closed
*/
log_error("accept on p %d failed: %s", p->sd, strerror(errno));
return NC_ERROR;
}
break;
}
c = conn_get(p->owner, true, p->redis);
if (c == NULL) {
log_error("get conn for c %d from p %d failed: %s", sd, p->sd,
strerror(errno));
status = close(sd);
if (status < 0) {
log_error("close c %d failed, ignored: %s", sd, strerror(errno));
}
return NC_ENOMEM;
}
c->sd = sd;
stats_pool_incr(ctx, c->owner, client_connections);
status = nc_set_nonblocking(c->sd);
if (status < 0) {
log_error("set nonblock on c %d from p %d failed: %s", c->sd, p->sd,
strerror(errno));
c->close(ctx, c);
return status;
}
if (p->family == AF_INET || p->family == AF_INET6) {
status = nc_set_tcpnodelay(c->sd);
if (status < 0) {
log_warn("set tcpnodelay on c %d from p %d failed, ignored: %s",
c->sd, p->sd, strerror(errno));
}
}
status = event_add_conn(ctx->center->ep, c);
if (status < 0) {
log_error("event add conn of c %d from p %d failed: %s", c->sd, p->sd,
strerror(errno));
c->close(ctx, c);
return status;
}
log_debug(LOG_NOTICE, "accepted c %d on p %d from '%s'", c->sd, p->sd,
nc_unresolve_peer_desc(c->sd));
return NC_OK;
}
//接收到客户端连接后，返回新的fd，为该fd创建新的conn来读取数据
static rstatus_t
proxy_accept(struct context *ctx, struct conn *p) //p对应的是proxy conn 也就是用于监听客户端的conn信息
{
rstatus_t status;
struct conn *c;
int sd;
struct server_pool *pool = p->owner;
ASSERT(p->proxy && !p->client);
ASSERT(p->sd > 0);
ASSERT(p->recv_active && p->recv_ready);
for (;;) {
sd = accept(p->sd, NULL, NULL); //获取到新的客户端连接，产生新的fd
if (sd < 0) {
if (errno == EINTR) {
log_debug(LOG_VERB, "accept on p %d not ready - eintr", p->sd);
continue;
}
if (errno == EAGAIN || errno == EWOULDBLOCK || errno == ECONNABORTED) {
log_debug(LOG_VERB, "accept on p %d not ready - eagain", p->sd);
p->recv_ready = 0;
return NC_OK;
}
/*
* Workaround of https://github.com/twitter/twemproxy/issues/97
*
* We should never reach here because the check for conn_ncurr_cconn()
* against ctx->max_ncconn should catch this earlier in the cycle.
* If we reach here ignore EMFILE/ENFILE, return NC_OK will enable
* the server continue to run instead of close the server socket
*
* The right solution however, is on EMFILE/ENFILE to mask out IN
* event on the proxy and mask it back in when some existing
* connections gets closed
*/
if (errno == EMFILE || errno == ENFILE) {
log_debug(LOG_CRIT, "accept on p %d with max fds %"PRIu32" "
"used connections %"PRIu32" max client connections %"PRIu32" "
"curr client connections %"PRIu32" failed: %s",
p->sd, ctx->max_nfd, conn_ncurr_conn(),
ctx->max_ncconn, conn_ncurr_cconn(), strerror(errno));
p->recv_ready = 0;
return NC_OK;
}
log_error("accept on p %d failed: %s", p->sd, strerror(errno));
return NC_ERROR;
}
break;
}
if (conn_ncurr_cconn() >= ctx->max_ncconn) {
log_debug(LOG_CRIT, "client connections %"PRIu32" exceed limit %"PRIu32,
conn_ncurr_cconn(), ctx->max_ncconn);
status = close(sd);
if (status < 0) {
log_error("close c %d failed, ignored: %s", sd, strerror(errno));
}
return NC_OK;
}
c = conn_get(p->owner, true, p->redis);
if (c == NULL) {
log_error("get conn for c %d from p %d failed: %s", sd, p->sd,
strerror(errno));
status = close(sd);
if (status < 0) {
log_error("close c %d failed, ignored: %s", sd, strerror(errno));
}
return NC_ENOMEM;
}
c->sd = sd;
stats_pool_incr(ctx, c->owner, client_connections);
status = nc_set_nonblocking(c->sd);
if (status < 0) {
log_error("set nonblock on c %d from p %d failed: %s", c->sd, p->sd,
strerror(errno));
c->close(ctx, c);
return status;
}
if (pool->tcpkeepalive) {
status = nc_set_tcpkeepalive(c->sd);
if (status < 0) {
log_warn("set tcpkeepalive on c %d from p %d failed, ignored: %s",
c->sd, p->sd, strerror(errno));
}
}
if (p->family == AF_INET || p->family == AF_INET6) {
status = nc_set_tcpnodelay(c->sd);
if (status < 0) {
log_warn("set tcpnodelay on c %d from p %d failed, ignored: %s",
c->sd, p->sd, strerror(errno));
}
}
status = event_add_conn(ctx->evb, c);
if (status < 0) {
log_error("event add conn from p %d failed: %s", p->sd,
strerror(errno));
c->close(ctx, c);
return status;
}
log_debug(LOG_INFO, "accepted c %d on p %d from '%s'", c->sd, p->sd,
nc_unresolve_peer_desc(c->sd));
return NC_OK;
}
static rstatus_t
proxy_accept(struct context *ctx, struct conn *p)
{
rstatus_t status;
struct conn *c;
int sd;
struct sockaddr_storage addr;
socklen_t addr_len;
ASSERT(p->proxy && !p->client);
ASSERT(p->sd > 0);
ASSERT(p->recv_active && p->recv_ready);
for (;;) {
sd = accept(p->sd, NULL, NULL);
if (sd < 0) {
if (errno == EINTR) {
log_debug(LOG_VERB, "accept on p %d not ready - eintr", p->sd);
continue;
}
if (errno == EAGAIN || errno == EWOULDBLOCK || errno == ECONNABORTED) {
log_debug(LOG_VERB, "accept on p %d not ready - eagain", p->sd);
p->recv_ready = 0;
return NC_OK;
}
/*
* FIXME: On EMFILE or ENFILE mask out IN event on the proxy; mask
* it back in when some existing connection gets closed
*/
/*
* Workaround of https://github.com/twitter/twemproxy/issues/97
* Just ignore EMFILE/ENFILE, return NC_OK will enable the server
* continue to run instead of close the server socket
*/
if (errno == EMFILE || errno == ENFILE) {
log_crit("accept on p %d failed: %s", p->sd,
strerror(errno));
p->recv_ready = 0;
log_crit("connections status: rlimit nofile %d, "
"used connections: %d, max client connections %d, "
"curr client connections %d", ctx->rlimit_nofile,
conn_ncurr(), ctx->max_ncconn, conn_ncurr_cconn());
/* Since we maintain a safe max_ncconn and check
* it after every accept, we should not reach here.
* So we will panic after this log */
log_panic("HIT MAX OPEN FILES, IT SHOULD NOT HAPPEN. ABORT.");
return NC_OK;
}
log_error("accept on p %d failed: %s", p->sd, strerror(errno));
return NC_ERROR;
}
addr_len = sizeof(addr);
if (getsockname(sd, (struct sockaddr *)&addr, &addr_len)) {
log_error("getsockname on p %d failed: %s", p->sd, strerror(errno));
close(sd);
continue;
}
break;
}
if (conn_ncurr_cconn() >= ctx->max_ncconn) {
stats_pool_incr(ctx, p->owner, rejected_connections);
log_crit("client connections %d exceed limit %d",
conn_ncurr_cconn(), ctx->max_ncconn);
status = close(sd);
if (status < 0) {
log_error("close c %d failed, ignored: %s", sd, strerror(errno));
}
return NC_OK;
}
c = conn_get(p->owner, true, p->redis);
if (c == NULL) {
log_error("get conn for c %d from p %d failed: %s", sd, p->sd,
strerror(errno));
status = close(sd);
if (status < 0) {
log_error("close c %d failed, ignored: %s", sd, strerror(errno));
}
return NC_ENOMEM;
}
c->sd = sd;
c->family = addr.ss_family;
c->addrlen = addr_len;
c->ss = addr;
c->addr = (struct sockaddr *)&c->ss;
stats_pool_incr(ctx, c->owner, client_connections);
status = nc_set_nonblocking(c->sd);
if (status < 0) {
log_error("set nonblock on c %d from p %d failed: %s", c->sd, p->sd,
strerror(errno));
c->close(ctx, c);
return status;
}
if (p->family == AF_INET || p->family == AF_INET6) {
status = nc_set_tcpnodelay(c->sd);
if (status < 0) {
log_warn("set tcpnodelay on c %d from p %d failed, ignored: %s",
c->sd, p->sd, strerror(errno));
}
}
status = event_add_conn(ctx->evb, c);
if (status < 0) {
log_error("event add conn from p %d failed: %s", p->sd,
strerror(errno));
c->close(ctx, c);
return status;
}
log_notice("accepted c %d on p %d from '%s'", c->sd, p->sd,
nc_unresolve_peer_desc(c->sd));
return NC_OK;
}