MSG_DONTWAIT (since Linux 2.2)
Enables nonblocking operation; if the operation would block, the
call fails with the error EAGAIN or EWOULDBLOCK. This provides
similar behavior to setting the O_NONBLOCK flag (via the fcntl(2)
F_SETFL operation), but differs in that MSG_DONTWAIT is a per-call
option, whereas O_NONBLOCK is a setting on the open file description
(see open(2)), which will affect all threads in the calling process
and as well as other processes that hold file descriptors referring
to the same open file description.
NuttX follows OpenGroup.org: https://pubs.opengroup.org/onlinepubs/009695399/functions/recv.html :
[EAGAIN] or [EWOULDBLOCK]
The socket's file descriptor is marked O_NONBLOCK and no data is waiting to be received; or MSG_OOB is set and no out-of-band data is available and either the socket's file descriptor is marked O_NONBLOCK or the socket does not support blocking to await out-of-band data.
ETIMEDOUT is not a valid error to be returned from recv() or recvfrom().
Author: chao.an <anchao@xiaomi.com>
net/udp: break the network lock to avoid deadlock
network deadlock when udp sendto() storm is coming
net/close: force wait tx drain to complete
atomic send() and close() will causes data to be discarded directly
Signed-off-by: chao.an <anchao@xiaomi.com>
1.Consolidate absolute to relative timeout conversion into one place(_net_timedwait)
2.Drive the wait timeout logic by net_timedwait instead of devif_timer
This patch help us remove devif_timer(period tick) to save the power in the future.
Change-Id: I534748a5d767ca6da8a7843c3c2f993ed9ea77d4
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
Here is the email loop talk about why it is better to remove the option:
https://groups.google.com/forum/#!topic/nuttx/AaNkS7oU6R0
Change-Id: Ib66c037752149ad4b2787ef447f966c77aa12aad
Signed-off-by: Xiang Xiao <xiaoxiang@xiaomi.com>
* Simplify EINTR/ECANCEL error handling
1. Add semaphore uninterruptible wait function
2 .Replace semaphore wait loop with a single uninterruptible wait
3. Replace all sem_xxx to nxsem_xxx
* Unify the void cast usage
1. Remove void cast for function because many place ignore the returned value witout cast
2. Replace void cast for variable with UNUSED macro
Author: Gregory Nutt <gnutt@nuttx.org>
Run all .h and .c files modified in last PR through nxstyle.
Author: Xiang Xiao <xiaoxiang@xiaomi.com>
Net cleanup (#17)
* Fix the semaphore usage issue found in tcp/udp
1. The count semaphore need disable priority inheritance
2. Loop again if net_lockedwait return -EINTR
3. Call nxsem_trywait to avoid the race condition
4. Call nxsem_post instead of sem_post
* Put the work notifier into free list to avoid the heap fragment in the long run. Since the allocation strategy is encapsulated internally, we can even refine the implementation later.
* Network stack shouldn't allocate memory in the poll implementation to avoid the heap fragment in the long run, other modification include:
1. Select MM_IOB automatically since ICMP[v6] socket can't work without the read ahead buffer
2. Remove the net lock since xxx_callback_free already do the same thing
3. TCP/UDP poll should work even the read ahead buffer isn't enabled at all
* Add NET_ prefix for UDP_NOTIFIER and TCP_NOTIFIER option to align with other UDP/TCP option convention
* Remove the unused _SF_[IDLE|ACCEPT|SEND|RECV|MASK] flags since there are code to set/clear these flags, but nobody check them.
Squashed commit of the following:
net/tmp: Rename the unacked field of the tcp connection structure to tx_unacked. Too confusing with the implementation of delayed RX ACKs.
net/tcp: Initial implementation of TCP delayed ACKs.
net/tcp: Add delayed ACK configuration selection. Rename tcp_ack() to tcp_synack(). It may or may not send a ACK. It will always send SYN or SYN/ACK.
1) The change of commit ed9fe70024 left some dangling logic and incorrect, confusing comments. Prior to that commit the 'pstate' variable was non-NULL only when doing a lingering close. Comments to this effect as well as tests of pstate should also have been updated. These are confusing and inappropriate, but do not lead to incorrect behavior.
2) Eliminate an incomplete test when a disconnection event. When a disconnection event occurs, the close logic MUST always terminate the wait. The conditional test was not incorrect, however, it lacked 'else' logic and would simply ignore that disconnection event in some cases. That is bad because there may not be another disconnection event and that can lead to hangs (or at least very, very long delays).
Iobinstrumentation
* mm/iob: Introduces producer/consumer id to every iob call. This is so that the calls can be instrumented to monitor the IOB resources.
* iob instrumentation - Merges producer/consumer enumeration for simpler IOB user.
* fs/procfs: Starts adding support for /proc/iobinfo
* fs/procfs: Finishes first pass of simple IOB user stastics and /proc/iobinfo entry
Approved-by: Gregory Nutt <gnutt@nuttx.org>
Squashed commit of the following:
net/: Fix some naming inconsistencies, Fix final compilation issies.
net/inet/inet_close(): Now that we have logic to drain the buffered TX data, we can implement a proper lingering close.
net/inet,tcp,udp: Add functions to wait for write buffers to drain.
net/udp: Add support for notification when the UDP write buffer becomes empty.
net/tcp: Add support for notification when the TCP write buffer becomes empty.
net/inet: Fix tcp active close in inet_close.c
In previous implementation, FIN packet was not sent when a socket
is actively closed (e.g. telnetd or webserver) without SO_LINGER.
This issue happens because the socket closing sequence waits for
the status.cl_sem only if lingering timeout is set. However,
in many server use-cases, SO_LINGER is not usually set and even
in these cases, FIN packet must be sent correctly.
This PR changes the logic in inet_close.c so that it can wait
for status.cl_sem regardless of SO_LINGER. Instead, if SO_LINGER
is set, it waits for the semaphore with timeout option.
Signed-off-by: Masayuki Ishikawa <Masayuki.Ishikawa@jp.sony.com>
Approved-by: Gregory Nutt <gnutt@nuttx.org>
arch/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
sched/ audio/ crypto/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
Documentation/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
fs/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
graphics/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
net/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
drivers/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
include/, syscall/, wireless/: Removed all references to CONFIG_DISABLE_POLL. The standard POSIX poll() can not longer be disabled.
configs/: Remove all references to CONFIG_DISABLE_POLL. Standard POSIX poll can no longer be disabled.
include/nuttx/net/ipv6ext.h: Fix some terminology: Hop-by-hop, not Hop-to-hop or Hop2hop.
net/devif/ipv6_input.c and net/icmpv6/icmpv6_input.c: Add logic to skiip over the variable number of IPv6 extension headers that may be present between the IPv6 header and the transport layer header. The extension headers are simply ignored. This is necessary because with MLD, certain incoming messages may have, at a mimimum, a Router Alert Hop-by-hop extension header.
net/inet/ipv6_setsockopt.c: Implement the IPV6_JOIN_GROUP and IPV6_LEAVE_GROUP socket options.
net/mld: The MLD logic now compiles and is much less toxic. It still is not a proper MLD implementation: (1) It is basically a port of IGMP, tweaked to work with IPv6 and ICMPv6 MLD messages, (2) it needs a proper analysis and comparison with RFC 3810, and (3) it is completely untested. For this reason, it will remain EXPERIMENTAL for some time.
net/mld: Add some missing macros, more fixes related to IPv6 vs IPv4 types,
net/mld: More compilation cleaning. Most fixups for IPv6 vs IPv4 types.
net/mld: Hook crudely converted .c files into build system and resolve a few of the many, many compilation/design problems.
net/mld: Add support for MLD statistics.
net/mld: Hook in MLD poll and packet transmission logic.
net/mld: Change references to IPv4 definitions to IPv6 definitions; Remove mld_input() since MLD piggybacks on ICMPv6 input. Add functions to catch MLD messages dispatched by ICMPv6 input logic.
net/mld: As a starting point, copy all net/igmp/*.c files to net/mld/. and change all occurrences of igmp (or IGMP) to mld (or MLD).
net/mld: More compilation cleaning. Most fixups for IPv6 vs IPv4 types.
net/mld: Hook crudely converted .c files into build system and resolve a few of the many, many compilation/design problems.
net/mld: Add support for MLD statistics.
net/mld: Hook in MLD poll and packet transmission logic.
net/mld: Change references to IPv4 definitions to IPv6 definitions; Remove mld_input() since MLD piggybacks on ICMPv6 input. Add functions to catch MLD messages dispatched by ICMPv6 input logic.
net/mld: As a starting point, copy all net/igmp/*.c files to net/mld/. and change all occurrences of igmp (or IGMP) to mld (or MLD).
Squashed commit of the following:
sched: Rename all use of system_t to clock_t.
syscall: Rename all use of system_t to clock_t.
net: Rename all use of system_t to clock_t.
libs: Rename all use of system_t to clock_t.
fs: Rename all use of system_t to clock_t.
drivers: Rename all use of system_t to clock_t.
arch: Rename all use of system_t to clock_t.
include: Remove definition of systime_t; rename all use of system_t to clock_t.
This commit adds logic to first check for UDP connection mode. If the UDP socket is connected, then the NULL 'to' address is ignored and saved connection address is used instead.
In connection-mode UDP sockets, a remote address is retained in the UDP connection structure. This determines both there send() will send the packets and which packets recv() will accept.
This same mechanism is used for connection-less UDP sendto: A temporary remote address is written into the connection structure to support the sendto() operation. That address persists until the next recvfrom() when it is reset to accept any address.
When UDP read-ahead buffering is enabled, however, that means that the old, invalid remote address can be left in the connection structure for some time. This can cause read-ahead buffer to fail, dropping UDP packets.
Shortening the time between when he remote address is reset (i.e., immediately after the sendto() completes) is not a solution, that does not eliminate the race condition; in only makes it smaller.
With this change, a flag was added to the connection structure to indicate if the UDP socket is in connection mode or if it is connection-less. This change effects only UDP receive operations: The remote address in the UDP connection is always ignored if the UDP socket is not in connection-mode.
No for connection-mode sockets, that remote address behaves as before. But for connection-less sockets, it is only used by sendto().
Squashed commit of the following:
net/udp: Address most of the issues with UDP write buffering. There is a remaining issue with handling one network going down in a multi-network environment. None of this has been test but it is certainly ready for test. Hence, the feature is marked EXPERIMENTAL.
net/udp: Some baby steps toward a corrected write buffering design.
net/udp: Remove pesky write buffer macros.
Eliminate trailing space at the end of lines.
net/udp: A little more UDP write buffering logic. Still at least on big gaping hole in the design.
net/udp: Undefined CONFIG_NET_SENDTO_TIMEOUT.
net/udp: Crude, naive port of the TCP write buffering logic into UDP. This commit is certainly non-functional and is simply a starting point for the implementatin of UDP write buffering.
net/udp: Rename udp/udp_psock_sendto.c udp/udp_psock_sendto_unbuffered.c.
Squashed commit of the following:
net/icmpv6: IPPROT_ICMP6 socket logic now builds without error.
net/icmpv6: Add support for read-ahead and poll(). Initial commit is just cloned from ICMP with the appropriate name changes.
configs/: All defconfig filess that include CONFIG_NET_ICMPv6_SOCKET=y need to select CONFIG_SYSTEM_PING6=y and deselect CONFIG_DISABLE_POLL.
Update NSH documention to show that ping6 is now a built in command.
net/icmpv6: Add icmpv6_sendto.c and icmpv6_recvfrom.c. Initial versions are just clones from icmp/ with appropriate name changes.
net/icmpv6: Clone some ICMP socket logic as the beginning of support for ICMPv6 socket support.
Rename CONFIG_NET_ICMPv6_PING to CONFIG_NET_ICMPv6_SOCKET. Move prototype for icmpv6_ping from include/nuttx/net/icmpv6 to net/icmpv6/icmpv6.h
Squashed commit of the following:
net/icmp: Finishes off icmp_recvfrom().
net/icmp: Add readahead support for IPPROTO_ICMP sockets.
net/icmp: Add poll() support for IPPROTO_ICMP sockets.
net/icmp: Add a connection structure for IPPROTO_ICMP sockets.
net/icmp: Implements sendto for the IPPROTO_ICMP socket.
net/icmp: Move icmp_sendto() and icmp_recvfrom() to separate files. They are likely to be complex (when they are implemented).
net/icmp: Hook IPPROTO_ICMP sockets into network. Fix some naming collisions. Still missing basic ICMP send/receive logic.
configs: apps/system/ping current need poll() enabled.
configs: All defconfig files that use to enable low-level support must now enabled CONFIG_SYSTEM_PING.
net/icmp: Adds basic build framework to support IPPROTO_ICMP sockets.
sched/semaphore: Add nxsem_post() which is identical to sem_post() except that it never modifies the errno variable. Changed all references to sem_post in the OS to nxsem_post().
sched/semaphore: Add nxsem_destroy() which is identical to sem_destroy() except that it never modifies the errno variable. Changed all references to sem_destroy() in the OS to nxsem_destroy().
libc/semaphore and sched/semaphore: Add nxsem_getprotocol() and nxsem_setprotocola which are identical to sem_getprotocol() and set_setprotocol() except that they never modifies the errno variable. Changed all references to sem_setprotocol in the OS to nxsem_setprotocol(). sem_getprotocol() was not used in the OS
libc/semaphore: Add nxsem_getvalue() which is identical to sem_getvalue() except that it never modifies the errno variable. Changed all references to sem_getvalue in the OS to nxsem_getvalue().
sched/semaphore: Rename all internal private functions from sem_xyz to nxsem_xyz. The sem_ prefix is (will be) reserved only for the application semaphore interfaces.
libc/semaphore: Add nxsem_init() which is identical to sem_init() except that it never modifies the errno variable. Changed all references to sem_init in the OS to nxsem_init().
sched/semaphore: Rename sem_tickwait() to nxsem_tickwait() so that it is clear this is an internal OS function.
sched/semaphoate: Rename sem_reset() to nxsem_reset() so that it is clear this is an internal OS function.