aboutsummaryrefslogtreecommitdiffstats
path: root/erts
diff options
context:
space:
mode:
authorSteve Vinoski <[email protected]>2013-08-27 11:42:00 -0400
committerLukas Larsson <[email protected]>2013-09-23 17:23:14 +0200
commit7fbf2c26ac063988818230a0e18a9df48c2fbf2d (patch)
tree8ee574a718eb61d7d99133e47a2a37bc1d94e115 /erts
parentcc3c34fce28062afcaadc288b69939ced8fd8cde (diff)
downloadotp-7fbf2c26ac063988818230a0e18a9df48c2fbf2d.tar.gz
otp-7fbf2c26ac063988818230a0e18a9df48c2fbf2d.tar.bz2
otp-7fbf2c26ac063988818230a0e18a9df48c2fbf2d.zip
add {active,N} socket option for TCP, UDP, and SCTP
Add the {active,N} socket option, where N is an integer in the range -32768..32767, to allow a caller to specify the number of data messages to be delivered to the controlling process. Once the socket's delivered message count either reaches 0 or is explicitly set to 0 with inet:setopts/2 or by including {active,0} as an option when the socket is created, the socket transitions to passive ({active, false}) mode and the socket's controlling process receives a message to inform it of the transition. TCP sockets receive {tcp_passive,Socket}, UDP sockets receive {udp_passive,Socket} and SCTP sockets receive {sctp_passive,Socket}. The socket's delivered message counter defaults to 0, but it can be set using {active,N} via any gen_tcp, gen_udp, or gen_sctp function that takes socket options as arguments, or via inet:setopts/2. New N values are added to the socket's current counter value, and negative numbers can be used to reduce the counter value. Specifying a number that would cause the socket's counter value to go above 32767 causes an einval error. If a negative number is specified such that the counter value would become negative, the socket's counter value is set to 0 and the socket transitions to passive mode. If the counter value is already 0 and inet:setopts(Socket, [{active,0}]) is specified, the counter value remains at 0 but the appropriate passive mode transition message is generated for the socket. This commit contains a modified preloaded prim_inet.beam due to changes in prim_inet.erl. Add tests for {active,N} mode for TCP, UDP, and SCTP sockets. Add documentation for {active,N} mode for inet, gen_tcp, gen_udp, and gen_sctp.
Diffstat (limited to 'erts')
-rw-r--r--erts/emulator/drivers/common/inet_drv.c119
-rw-r--r--erts/preloaded/src/prim_inet.erl20
2 files changed, 125 insertions, 14 deletions
diff --git a/erts/emulator/drivers/common/inet_drv.c b/erts/emulator/drivers/common/inet_drv.c
index 60db50e80a..7dcb191a83 100644
--- a/erts/emulator/drivers/common/inet_drv.c
+++ b/erts/emulator/drivers/common/inet_drv.c
@@ -86,6 +86,13 @@
#endif
typedef unsigned long long llu_t;
+#ifndef INT16_MIN
+#define INT16_MIN (-32768)
+#endif
+#ifndef INT16_MAX
+#define INT16_MAX (32767)
+#endif
+
#ifdef __WIN32__
#define STRNCASECMP strncasecmp
@@ -581,6 +588,7 @@ static int my_strncasecmp(const char *s1, const char *s2, size_t n)
#define INET_PASSIVE 0 /* false */
#define INET_ACTIVE 1 /* true */
#define INET_ONCE 2 /* true; active once then passive */
+#define INET_MULTI 3 /* true; active N then passive */
/* INET_REQ_GETSTATUS enumeration */
#define INET_F_OPEN 0x0001
@@ -925,6 +933,7 @@ typedef struct {
inet_async_op op_queue[INET_MAX_ASYNC]; /* call queue */
int active; /* 0 = passive, 1 = active, 2 = active once */
+ Sint16 active_count; /* counter for {active,N} */
int stype; /* socket type:
SOCK_STREAM/SOCK_DGRAM/SOCK_SEQPACKET */
int sprotocol; /* socket protocol:
@@ -1160,22 +1169,36 @@ static int packet_inet_output(udp_descriptor* udesc, HANDLE event);
static int async_ref = 0; /* async reference id generator */
#define NEW_ASYNC_ID() ((async_ref++) & 0xffff)
+/* check for transition from active to passive */
+#define INET_CHECK_ACTIVE_TO_PASSIVE(inet) \
+ do { \
+ if ((inet)->active == INET_ONCE) \
+ (inet)->active = INET_PASSIVE; \
+ else if ((inet)->active == INET_MULTI && --((inet)->active_count) == 0) { \
+ (inet)->active = INET_PASSIVE; \
+ packet_passive_message(inet); \
+ } \
+ } while (0)
static ErlDrvTermData am_ok;
static ErlDrvTermData am_tcp;
static ErlDrvTermData am_udp;
static ErlDrvTermData am_error;
+static ErlDrvTermData am_einval;
static ErlDrvTermData am_inet_async;
static ErlDrvTermData am_inet_reply;
static ErlDrvTermData am_timeout;
static ErlDrvTermData am_closed;
+static ErlDrvTermData am_tcp_passive;
static ErlDrvTermData am_tcp_closed;
static ErlDrvTermData am_tcp_error;
+static ErlDrvTermData am_udp_passive;
static ErlDrvTermData am_udp_error;
static ErlDrvTermData am_empty_out_q;
static ErlDrvTermData am_ssl_tls;
#ifdef HAVE_SCTP
static ErlDrvTermData am_sctp;
+static ErlDrvTermData am_sctp_passive;
static ErlDrvTermData am_sctp_error;
static ErlDrvTermData am_true;
static ErlDrvTermData am_false;
@@ -1185,6 +1208,7 @@ static ErlDrvTermData am_list;
static ErlDrvTermData am_binary;
static ErlDrvTermData am_active;
static ErlDrvTermData am_once;
+static ErlDrvTermData am_multi;
static ErlDrvTermData am_buffer;
static ErlDrvTermData am_linger;
static ErlDrvTermData am_recbuf;
@@ -3337,6 +3361,34 @@ static int packet_binary_message
}
/*
+** active mode message: send active-to-passive transition message
+** {tcp_passive, S} or
+** {udp_passive, S} or
+** {sctp_passive, S}
+*/
+ static int packet_passive_message(inet_descriptor* desc)
+ {
+ ErlDrvTermData spec[6];
+ int i = 0;
+
+ DEBUGF(("packet_passive_message(%ld):\r\n", (long)desc->port));
+
+ if (desc->sprotocol == IPPROTO_TCP)
+ i = LOAD_ATOM(spec, i, am_tcp_passive);
+ else {
+#ifdef HAVE_SCTP
+ i = LOAD_ATOM(spec, i, IS_SCTP(desc) ? am_sctp_passive : am_udp_passive);
+#else
+ i = LOAD_ATOM(spec, i, am_udp_passive);
+#endif
+ }
+ i = LOAD_PORT(spec, i, desc->dport);
+ i = LOAD_TUPLE(spec, i, 2);
+ ASSERT(i <= 6);
+ return erl_drv_output_term(desc->dport, spec, i);
+ }
+
+/*
** send active message {udp_error|sctp_error, S, Error}
*/
static int packet_error_message(udp_descriptor* udesc, int err)
@@ -3378,7 +3430,7 @@ static int tcp_reply_data(tcp_descriptor* desc, char* buf, int len)
int code;
const char* body = buf;
int bodylen = len;
-
+
packet_get_body(desc->inet.htype, &body, &bodylen);
if (desc->inet.deliver == INET_DELIVER_PORT) {
@@ -3396,8 +3448,7 @@ static int tcp_reply_data(tcp_descriptor* desc, char* buf, int len)
if (code < 0)
return code;
- if (desc->inet.active == INET_ONCE)
- desc->inet.active = INET_PASSIVE;
+ INET_CHECK_ACTIVE_TO_PASSIVE(INETP(desc));
return code;
}
@@ -3424,8 +3475,7 @@ tcp_reply_binary_data(tcp_descriptor* desc, ErlDrvBinary* bin, int offs, int len
}
if (code < 0)
return code;
- if (desc->inet.active == INET_ONCE)
- desc->inet.active = INET_PASSIVE;
+ INET_CHECK_ACTIVE_TO_PASSIVE(INETP(desc));
return code;
}
@@ -3448,8 +3498,7 @@ packet_reply_binary_data(inet_descriptor* desc, unsigned int hsz,
code = packet_binary_message(desc, bin, offs, len, extra);
if (code < 0)
return code;
- if (desc->active == INET_ONCE)
- desc->active = INET_PASSIVE;
+ INET_CHECK_ACTIVE_TO_PASSIVE(desc);
return code;
}
}
@@ -3494,6 +3543,7 @@ sock_init(void) /* May be called multiple times. */
#ifdef HAVE_SCTP
static void inet_init_sctp(void) {
INIT_ATOM(sctp);
+ INIT_ATOM(sctp_passive);
INIT_ATOM(sctp_error);
INIT_ATOM(true);
INIT_ATOM(false);
@@ -3503,6 +3553,7 @@ static void inet_init_sctp(void) {
INIT_ATOM(binary);
INIT_ATOM(active);
INIT_ATOM(once);
+ INIT_ATOM(multi);
INIT_ATOM(buffer);
INIT_ATOM(linger);
INIT_ATOM(recbuf);
@@ -3628,12 +3679,15 @@ static int inet_init()
INIT_ATOM(tcp);
INIT_ATOM(udp);
INIT_ATOM(error);
+ INIT_ATOM(einval);
INIT_ATOM(inet_async);
INIT_ATOM(inet_reply);
INIT_ATOM(timeout);
INIT_ATOM(closed);
+ INIT_ATOM(tcp_passive);
INIT_ATOM(tcp_closed);
INIT_ATOM(tcp_error);
+ INIT_ATOM(udp_passive);
INIT_ATOM(udp_error);
INIT_ATOM(empty_out_q);
INIT_ATOM(ssl_tls);
@@ -5508,8 +5562,25 @@ static int inet_set_opts(inet_descriptor* desc, char* ptr, int len)
case INET_LOPT_ACTIVE:
DEBUGF(("inet_set_opts(%ld): s=%d, ACTIVE=%d\r\n",
- (long)desc->port, desc->s,ival));
+ (long)desc->port, desc->s, ival));
desc->active = ival;
+ if (desc->active == INET_MULTI) {
+ long ac = desc->active_count;
+ Sint16 nval = get_int16(ptr);
+ ptr += 2;
+ len -= 2;
+ ac += nval;
+ if (ac > INT16_MAX || ac < INT16_MIN)
+ return -1;
+ desc->active_count += nval;
+ if (desc->active_count < 0)
+ desc->active_count = 0;
+ if (desc->active_count == 0) {
+ desc->active = INET_PASSIVE;
+ packet_passive_message(desc);
+ }
+ } else
+ desc->active_count = 0;
if ((desc->stype == SOCK_STREAM) && (desc->active != INET_PASSIVE) &&
(desc->state == INET_STATE_CLOSED)) {
tcp_closed_message((tcp_descriptor *) desc);
@@ -5820,7 +5891,8 @@ static int inet_set_opts(inet_descriptor* desc, char* ptr, int len)
/* XXX fprintf(stderr,"desc->htype == %d, old_htype == %d,
desc->active == %d, old_active == %d\r\n",(int)desc->htype,
(int) old_htype, (int) desc->active, (int) old_active );*/
- return 1+(desc->htype == old_htype && desc->active == INET_ONCE);
+ return 1+(desc->htype == old_htype &&
+ (desc->active == INET_ONCE || desc->active == INET_MULTI));
}
return 0;
}
@@ -5953,6 +6025,21 @@ static int sctp_set_opts(inet_descriptor* desc, char* ptr, int len)
case INET_LOPT_ACTIVE:
desc->active = get_int32(curr); curr += 4;
+ if (desc->active == INET_MULTI) {
+ long ac = desc->active_count;
+ Sint16 nval = get_int16(curr); curr += 2;
+ ac += nval;
+ if (ac > INT16_MAX || ac < INT16_MIN)
+ return -1;
+ desc->active_count += nval;
+ if (desc->active_count < 0)
+ desc->active_count = 0;
+ if (desc->active_count == 0) {
+ desc->active = INET_PASSIVE;
+ packet_passive_message(desc);
+ }
+ } else
+ desc->active_count = 0;
res = 0;
continue;
@@ -6475,6 +6562,11 @@ static ErlDrvSSizeT inet_fill_opts(inet_descriptor* desc,
case INET_LOPT_ACTIVE:
*ptr++ = opt;
put_int32(desc->active, ptr);
+ if (desc->active == INET_MULTI) {
+ PLACE_FOR(2,ptr);
+ put_int16(desc->active_count, ptr);
+ ptr += 2;
+ }
continue;
case INET_LOPT_PACKET:
*ptr++ = opt;
@@ -6847,7 +6939,10 @@ static ErlDrvSSizeT sctp_fill_opts(inet_descriptor* desc,
}
case INET_LOPT_ACTIVE:
{
- PLACE_FOR(spec, i, 2*LOAD_ATOM_CNT + LOAD_TUPLE_CNT);
+ if (desc->active == INET_MULTI)
+ PLACE_FOR(spec, i, LOAD_ATOM_CNT + LOAD_INT_CNT + LOAD_TUPLE_CNT);
+ else
+ PLACE_FOR(spec, i, 2*LOAD_ATOM_CNT + LOAD_TUPLE_CNT);
i = LOAD_ATOM (spec, i, am_active);
switch (desc->active)
{
@@ -6860,6 +6955,9 @@ static ErlDrvSSizeT sctp_fill_opts(inet_descriptor* desc,
case INET_ONCE :
{ i = LOAD_ATOM (spec, i, am_once); break; }
+ case INET_MULTI :
+ { i = LOAD_INT(spec, i, desc->active_count); break; }
+
default: ASSERT (0);
}
i = LOAD_TUPLE (spec, i, 2);
@@ -7656,6 +7754,7 @@ static ErlDrvData inet_start(ErlDrvPort port, int size, int protocol)
socket */
desc->deliver = INET_DELIVER_TERM; /* standard term format */
desc->active = INET_PASSIVE; /* start passive */
+ desc->active_count = 0;
desc->oph = NULL;
desc->opt = NULL;
diff --git a/erts/preloaded/src/prim_inet.erl b/erts/preloaded/src/prim_inet.erl
index fa621681f3..69eed716ff 100644
--- a/erts/preloaded/src/prim_inet.erl
+++ b/erts/preloaded/src/prim_inet.erl
@@ -1237,7 +1237,8 @@ type_opt_1(buffer) -> int;
type_opt_1(active) ->
{enum,[{false, ?INET_PASSIVE},
{true, ?INET_ACTIVE},
- {once, ?INET_ONCE}]};
+ {once, ?INET_ONCE},
+ {multi, ?INET_MULTI}]};
type_opt_1(packet) ->
{enum,[{0, ?TCP_PB_RAW},
{1, ?TCP_PB_1},
@@ -1716,11 +1717,14 @@ encode_opt_val(Opts) ->
Reason -> {error,Reason}
end.
+%% {active, once} and {active, N} are specially optimized because they will
+%% be used for every packet or every N packets, not only once when
+%% initializing the socket. Measurements show that this optimization is
+%% worthwhile.
enc_opt_val([{active,once}|Opts], Acc) ->
- %% Specially optimized because {active,once} will be used for
- %% every packet, not only once when initializing the socket.
- %% Measurements show that this optimization is worthwhile.
enc_opt_val(Opts, [<<?INET_LOPT_ACTIVE:8,?INET_ONCE:32>>|Acc]);
+enc_opt_val([{active,N}|Opts], Acc) when is_integer(N), N < 32768, N >= -32768 ->
+ enc_opt_val(Opts, [<<?INET_LOPT_ACTIVE:8,?INET_MULTI:32,N:16>>|Acc]);
enc_opt_val([{raw,P,O,B}|Opts], Acc) ->
enc_opt_val(Opts, Acc, raw, {P,O,B});
enc_opt_val([{Opt,Val}|Opts], Acc) ->
@@ -1810,6 +1814,14 @@ dec_opt_val([]) -> [].
dec_opt_val(Buf, raw, Type) ->
{{P,O,B},T} = dec_value(Type, Buf),
[{raw,P,O,B}|dec_opt_val(T)];
+dec_opt_val(Buf, active, Type) ->
+ case dec_value(Type, Buf) of
+ {multi,[M0,M1|T]} ->
+ <<N:16>> = list_to_binary([M0,M1]),
+ [{active,N}|dec_opt_val(T)];
+ {Val,T} ->
+ [{active,Val}|dec_opt_val(T)]
+ end;
dec_opt_val(Buf, Opt, Type) ->
{Val,T} = dec_value(Type, Buf),
[{Opt,Val}|dec_opt_val(T)].