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Signed-off-by: harmon25 <dougwright1@gmail.com>
Make socket:send/2 retry partial stream sends and wait for write readiness when the native send path reports eagain. This keeps gen_tcp callers on the OTP-like success path instead of leaking {ok, Rest} or transient backpressure.
Add write-select plumbing for BSD and lwIP, including distinct read/write select state and lwIP tcp_sent/tcp_poll wakeups. Use the same readiness wait for SSL WANT_WRITE and make distribution/EPMD send failures explicit instead of dropping data.
Signed-off-by: Peter M <petermm@gmail.com>
Signed-off-by: Peter M <petermm@gmail.com>
Blocking sends require read and write readiness to coexist on one socket. Sharing their owner lets a writer replace a reader, misroutes close notifications, and cancels both directions when one selector exits. Give each direction its own owner, monitor and reference, initialized for both opened and accepted sockets. Implement ERL_NIF_SELECT_CANCEL so selector death cancels only its direction, disposes its pending message, and leaves the other direction armed. Retain socket resources while lwIP write/error events are queued and detach callbacks on close. Notify established-socket waiters of terminal errors through direction-specific abort messages, independently of the connect trap. Keep distribution output event-driven so backpressure cannot block incoming traffic or ticks. Preserve pending frame suffixes and queue ticks behind them to maintain byte ordering. Send empty binaries through the native socket path so closed sockets still fail and connected UDP sockets transmit zero-length datagrams. Add regressions for accepted-socket close, writer death, both selector registration orders, exact-data backpressure recovery, cancellation cleanup, and empty UDP sends. Move the changelog entry to beta.1. See also: atomvm#2345 Signed-off-by: Peter M <petermm@gmail.com>
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A cancelled selection retains its event for reuse. If the operating system later assigns the same descriptor to another resource, dispatch can find the inactive registration first and silently lose readiness for the new socket. Match only registrations that are open and armed for a reported direction. Extend the cancellation regression to verify that another resource using the same event receives readiness and both resources are released. Evaluate the test heap reservations outside assert expressions so assert macro expansion does not introduce duplicate unevaluated calls into the allocation-budget analysis. Signed-off-by: Peter M <petermm@gmail.com>
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lwIP can free a TCP PCB before task-context error handling runs. Queuing raw PCBs or treating listeners as connections can therefore corrupt memory. Taking the VM socket lock from a callback would also invert the task-context lock order. A full wake queue must not turn an accepted payload into a failed enqueue and cause its resource reference to be released twice. Invalidate reset PCBs in the lwIP synchronization domain and retain socket resources for deferred work without resurrecting dying resources. Keep notification and monitor cleanup in task context. Use stable pending-accept slots to preserve pre-accept EOF and discard reset children without closing the listener. Retain critical work independently of the bounded payload queue. Leave refused TCP buffers with lwIP, make RP2 wakeups durable, and report payload acceptance independently of global wake hints. Share the RP2 CAS lock across translation units and protect reference updates from interrupts in single-scheduler builds as well. Detach callbacks according to the PCB type and guard PCB access with the lwIP lock. Preserve bytes accepted by tcp_write when tcp_output fails so callers cannot duplicate them on retry. Release replaced selector monitors and inactive BSD events on close, and provide read-only selection cancellation for the public receive wrappers. Signed-off-by: Peter M <petermm@gmail.com>
Receive and accept error cleanup currently stops both selections on a socket. A read-side EOF can consequently strand an independent writer that is waiting for its peer to drain buffered data. Cancel only the read selection in these cleanup paths. Keep the public send contract as ok or an error; document that sendto/3 is unchanged. Exercise the public receive path with a blocked public send in both selector registration orders. Fill the socket until backpressure is observed rather than relying on a fixed payload size, then verify that half-close preserves the writer and draining delivers every queued byte and the final marker. Keep close and writer-death coverage alongside this regression. The half-close case times out with the old socket wrapper and passes with read-only cleanup. Update the changelog with the user-visible half-close behavior. Signed-off-by: Peter M <petermm@gmail.com>
sendto/3 currently exposes transient backpressure instead of waiting for acceptance like the default OTP call. Retrying a partial result as a new datagram would also change packet boundaries. Wait for write readiness and retry the original payload and destination. Keep empty datagrams on the native path and return partial results without resending their tails. Back off retries for 10 ms because raw lwIP reports UDP write readiness immediately even after ERR_MEM. Reject oversized IPv4 UDP payloads before conversion to lwIP packet lengths, and preserve BSD sendto errors instead of reporting them as closed sockets. Extend the UDP tests for empty and iodata packets, oversized rejection, and sends on closed sockets. Signed-off-by: Peter M <petermm@gmail.com>
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little bit of mess with these PRs - so lets land a single one
fixes a plethora of issues with httpd etc.
this is the (original) work from #2345 (that PR was a git history rewrite of my work) progressed to PR readiness, also relates to #2416
These changes are made under both the "Apache 2.0" and the "GNU Lesser General
Public License 2.1 or later" license terms (dual license).
SPDX-License-Identifier: Apache-2.0 OR LGPL-2.1-or-later