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2018-12-12Add empty 'since' attribute for old modules and functionsSverker Eriksson
2018-09-04Implement socket option recvtos and friendsRaimo Niskanen
Implement socket options recvtclass, recvtos, recvttl and pktoptions. Document the implemented socket options, new types and message formats. The options recvtclass, recvtos and recvttl are boolean options that when activated (true) for a socket will cause ancillary data to be received through recvmsg(). That is for packet oriented sockets (UDP and SCTP). The required options for this feature were recvtclass and recvtos, and recvttl was only added to test that the ancillary data parsing handled multiple data items in one message correctly. These options does not work on Windows since ancillary data is not handled by the Winsock2 API. For stream sockets (TCP) there is no clear connection between a received packet and what is returned when reading data from the socket, so recvmsg() is not useful. It is possible to get the same ancillary data through a getsockopt() call with the IPv6 socket option IPV6_PKTOPTIONS, on Linux named IPV6_2292PKTOPTIONS after the now obsoleted RFC where it originated. (unfortunately RFC 3542 that obsoletes it explicitly undefines this way to get packet ancillary data from a stream socket) Linux also has got a way to get packet ancillary data for IPv4 TCP sockets through a getsockopt() call with IP_PKTOPTIONS, which appears to be Linux specific. This implementation uses a flag field in the inet_drv.c socket internal data that records if any setsockopt() call with recvtclass, recvtos or recvttl (IPV6_RECVTCLASS, IP_RECVTOS or IP_RECVTTL) has been activated. If so recvmsg() is used instead of recvfrom(). Ancillary data is delivered to the application by a new return tuple format from gen_udp:recv/2,3 containing a list of ancillary data tuples [{tclass,TCLASS} | {tos,TOS} | {ttl,TTL}], as returned by recvmsg(). For a socket in active mode a new message format, containing the ancillary data list, delivers the data in the same way. For gen_sctp the ancillary data is delivered in the same way, except that the gen_sctp return tuple format already contained an ancillary data list so there are just more possible elements when using these socket options. Note that the active mode message format has got an extra tuple level for the ancillary data compared to what is now implemented gen_udp. The gen_sctp active mode format was considered to be the odd one - now all tuples containing ancillary data are flat, except for gen_sctp active mode. Note that testing has not shown that Linux SCTP sockets deliver any ancillary data for these socket options, so it is probably not implemented yet. Remains to be seen what FreeBSD does... For gen_tcp inet:getopts([pktoptions]) will deliver the latest received ancillary data for any activated socket option recvtclass, recvtos or recvttl, on platforms where IP_PKTOPTIONS is defined for an IPv4 socket, or where IPV6_PKTOPTIONS or IPV6_2292PKTOPTIONS is defined for an IPv6 socket. It will be delivered as a list of ancillary data items in the same way as for gen_udp (and gen_sctp). On some platforms, e.g the BSD:s, when you activate IP_RECVTOS you get ancillary data tagged IP_RECVTOS with the TOS value, but on Linux you get ancillary data tagged IP_TOS with the TOS value. Linux follows the style of RFC 2292, and the BSD:s use an older notion. For RFC 2292 that defines the IP_PKTOPTIONS socket option it is more logical to tag the items with the tag that is the item's, than with the tag that defines that you want the item. Therefore this implementation translates all BSD style ancillary data tags to the corresponding Linux style data tags, so the application will only see the tags 'tclass', 'tos' and 'ttl' on all platforms.
2016-10-27controlling_process can return {error, badarg}Péter Gömöri
For gen_tcp, gen_udp and gen_sctp controlling_process/2 can return badarg if erlang:port_connect/2 fails with badarg. This can easily happen if the new owner is not alive but in some race condition also when the socket is closed right before port_connect/2 (and after the previous socket function) This commit documents this behaviour.
2016-06-09Document the local (unix) address familyRaimo Niskanen
2016-06-02Merge branch 'saleyn/uds/PR-612/OTP-13572'Raimo Niskanen
* saleyn/uds/PR-612/OTP-13572: Rewrite inet* for address family 'local' Rewrite inet_drv for AF_LOCAL Assign externally open fd to gen_tcp (UDS support) Conflicts: erts/preloaded/ebin/prim_inet.beam lib/kernel/doc/src/gen_tcp.xml lib/kernel/doc/src/gen_udp.xml lib/kernel/src/inet6_sctp.erl lib/kernel/test/inet_SUITE.erl
2016-05-17kernel: Remove no longer needed anchors in documentationHans Bolinder
2016-04-13Merge branch 'henrik/update-copyrightyear'Henrik Nord
* henrik/update-copyrightyear: update copyright-year
2016-03-31Update Kernel documentationBjörn Gustavsson
Language cleaned up by technical writers from Combitech. Proofreading and corrections by Björn Gustavsson and Hans Bolinder.
2016-03-15update copyright-yearHenrik Nord
2016-01-12Assign externally open fd to gen_tcp (UDS support)Serge Aleynikov
When a AF_LOCAL file descriptor is created externally (e.g. Unix Domain Socket) and passed to `gen_tcp:listen(0, [{fd, FD}])`, the implementation incorrectly assigned the address family to be equal to `inet`, which in the inet_drv driver translated to AF_INET instead of AF_LOCAL (or AF_UNIX), and an `einval` error code was returned. This patch fixes this problem such that the file descriptors of the `local` address family are supported in the inet:fdopen/5, gen_tcp:connect/3, gen_tcp:listen/2, gen_udp:open/2 calls
2015-11-04[kernel] Correct documentationHans Bolinder
Fix mistakes found by 'xmllint'.
2015-06-18Change license text to APLv2Bruce Yinhe
2014-08-06erts: Fix tc and docs after {fd,FD} bind changeLukas Larsson
The sha of the original change is 52810718b
2013-09-23add {active,N} socket option for TCP, UDP, and SCTPSteve Vinoski
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.
2013-04-19Convert XML files to UTF-8Hans Bolinder
2012-08-31Update copyright yearsBjörn-Egil Dahlberg
2012-05-23Merge branch 'lukas/kernel/fix-gen_udp_tcp-leak/OTP-10094' into maintLukas Larsson
* lukas/kernel/fix-gen_udp_tcp-leak/OTP-10094: Add testcase for controlling_process(P,self()) Fix port leaking after controlling_process(Port, self())
2012-04-17doc: Add 'is' to explanation of callback modulesBjörn-Egil Dahlberg
2012-04-16kernel: Document ifaddr optionBjörn-Egil Dahlberg
* same as ip option
2012-04-16kernel: Document tcp-, udp- and sctp_module optionBjörn-Egil Dahlberg
2012-04-12kernel: Initial doc of forgotten inet optionsBjörn-Egil Dahlberg
* UDP: ulticast_if, multicast_loop and multicast_ttl, add_membership and drop_membership * Inet: bit8, buffer, deliver, high_watermark, linger and low_watermark
2012-02-04Fix port leaking after controlling_process(Port, self())Ricardo
Add case to handle the situation when someone call {gen_tcp,gen_udp}:controlling_process(Port, self()). Also improve spec and doc from gen_udp and gen_sctp for controlling_process/2. To reproduce the issue, open an UDP port: 4> {ok,Port} = gen_udp:open(9000, [binary]). {ok,#Port<0.587>} 5> gen_udp:controlling_process(Port, self()). ok Simulate error: 6> 1=2. ** exception error: no match of right hand side value 2 Here is the leak: 7> inet:i(). Port Module Recv Sent Owner Local Address Foreign Address State Type 581 inet_udp 0 0 <0.31.0> *:cslistener *:* BOUND DGRAM ok
2011-08-25Improve types and specifications of the inet modulesHans Bolinder
2011-05-11Use Erlang specs and types for documentationHans Bolinder
2009-11-20The R13B03 release.OTP_R13B03Erlang/OTP