hell

# Changelog

## Hell 0.1.2

- Preserve the listening socket when the acceptor pool restarts, so supervision
  can recover without taking down the server.
- Clean up handlers whose acceptor exits before completing socket handoff,
  preserving connection capacity across suspension and acceptor failures.
- Apply `handshake_timeout` to TCP-to-TLS upgrades. Add an optional transport
  `upgrade/3` callback while retaining support for existing `upgrade/2` transports.
- Honor one-shot and persistent read timeout overrides after transport upgrades,
  independently of GenServer mailbox timeouts.
- Accept raw socket options without merging distinct native options.
- Enforce the documented binary mode for bare `:list` and `:binary` aliases as
  well as `mode` tuples on TCP and TLS listeners.

Existing handler callbacks, startup/readiness messages and required transport
callbacks remain compatible. Stalled TLS upgrades now close after the configured
handshake deadline; `handshake_timeout: :infinity` restores unbounded waiting.
Callers relying on the unintended `:list` override now receive binary data.

## Hell 0.1.1

- Add copyright (c) 2026 GSMLG Limited for Hell fork contributions while retaining
  Mat Trudel's original copyright notice and every MIT permission and warranty term.
- Publish updates to the existing `hell` package through the manual release
  workflow, validating repository/package identity and unpublished release versions.
- Refresh CI cache identity for the resolved toolchain to prevent reuse of
  incompatible Dialyzer PLTs.
- Synchronize the synchronous receive-timeout fixture with a handler-entry
  acknowledgment and use an elapsed-time send schedule and absolute ping deadlines
  in handler tests on macOS; start timer-reset log capture before connection and
  traffic.
- Correct an inherited shutdown telemetry race by waiting for acceptor cleanup
  before pool teardown, using the existing stop-event emission and retaining the
  5000ms shutdown-listener child bound.

This intentionally adds orderly shutdown waiting within that existing child
bound and can affect shutdown latency. Dependency versions, socket options,
connection ownership, configured connection shutdown timeouts and the Elixir
`>= 1.18.0` requirement are unchanged. Publication requires workflow validation
and the explicit gates described in [RELEASE.md](https://github.com/gsmlg-dev/hell/blob/main/RELEASE.md).

## Hell 0.1.0 (14 Oct 2026)

Hell is derived from [Thousand Island](https://github.com/mtrudel/thousand_island)
at commit `e3eb2a7a05f98d79436abcefd8c954da2f8b05c0`. The project, Elixir
namespace, OTP application and intended Hex package have been renamed to Hell,
`Hell` and `hell`. See [MIGRATION.md](MIGRATION.md) for consumer changes.
That initial identity migration preserved runtime behavior and dependency
versions.

The upstream baseline version is `1.5.0`; `0.1.0` is the first Hell release
version. Hell requires Elixir `>= 1.18.0` instead of the upstream `~> 1.13`
requirement. The fork maintainer published this first Hell package locally to
Hex; its documentation is available at https://hexdocs.pm/hell/0.1.0/.

## Upstream Thousand Island history

All entries below describe releases of Thousand Island, not Hell. Module names,
telemetry names, issue numbers and contributor credits retain their historical
meaning; issue numbers refer to the upstream repository. The history is preserved
as received, including references to APIs subsequently removed upstream.

## 1.5.0 (1 Jun 2026)

### Changes

* **Not-strictly-breaking-but-still-important-change**: We've improved the
isolation between network-related timeouts and GenServer-related timeouts.
Specifically, local GenServer callbacks (handle_info et al) no longer affect
network-related timeouts; a 30s network timeout will be enforced after 30
seconds, regardless of how many local messages arrive in the process' mailbox.
See #202 for more details.

## 1.4.3 (12 Dec 2025)

### Enhancements

* Add support for setting process labels for better observer visibility (#188, thanks @NelsonVides and @nathanl!)
* Improve memory usage and performance (#181 & #182, thanks @NelsonVides!)

## 1.4.2 (19 Oct 2025)

### Changes

* Resolve compiler warnings in Elixir 1.19 (#171, thanks @psantos10!)

## 1.4.1 (4 Sept 2025)

### Enhancements

* Improve performance of SSL sendfile function on larger files (#176, thanks @NelsonVides!)

## 1.4.0 (22 Aug 2025)

### Enhancements

* Add `num_listen_sockets` parameter to allow for improved performance on
specific systems (#174, thanks @NelsonVides!)

## 1.3.14 (25 May 2025)

### Enhancements

* Add support for `ThousandIsland.Socket.connection_information/1` to get info
about the underlying SSL connection, if one is present.

## 1.3.13 (29 Apr 2025)

### Enhancements

* Allow `handle_connection` and `handle_data` callbacks to return tuples to call
  `handle_continue` per GenServer conventions (#166)

## 1.3.12 (21 Mar 2025)

### Fixes

* Do not kill off acceptors when encountering an `:einval` socket status (#162,
  thanks @marschro!)

## 1.3.11 (23 Feb 2025)

### Fixes

* Properly support `inet_backend` transport option for TCP connections (#155, thanks @paulswartz!)

## 1.3.10 (17 Feb 2025)

### Enhancements

* Add support for `certs_keys` TLS config option (#153, thanks @joshk!)

## 1.3.9 (6 Jan 2025)

### Fixes

* Explicitly ignore several Handler return values to silence Dialyzer in dependent libraries

## 1.3.8 (5 Jan 2025)

### Changes

* Refactor `ThousandIsland.Handler` implementation to facilitate partial reuse
by custom Handler authors (#146 thanks @mruoss!)

## 1.3.7 (29 Nov 2024)

### Fixes

* Use socket as returned from transport handshake (#142, thanks @danielspofford!)

## 1.3.6 (18 Nov 2024)

### Fixes

* Don't consider remote end closure as an error condition for telemetry
* Fix typo & clarify docs (#117)
* Update security policy (#138)

## 1.3.5 (24 Feb 2024)

### Fixes

* Fix regression on non-keyword options (such as `:inet6`) introduced in 1.3.4
  (#113, thanks @danschultzer!)

## 1.3.4 (23 Feb 2024)

### Fixes

* Fix the ability to override default options (and not override hardcoded
  options) for both TCP and SSL transports (#111, thanks @moogle19!)

## 1.3.3 (21 Feb 2024)

### Changes

* Do not set `:linger` as a default option on either TCP or SSL transports. This
  was causing oddball node hangs on larger instances (#110, thanks @jonjon &
  @pojiro!)

## 1.3.2 (31 Dec 2023)

### Changes

* Allow `sni_hosts` or `sni_fun` in place of `cert`/`certfile` and
  `key`/`keyfile`

### Fixes

* Move `handle_info` fallback clause to module compilation hook (#105)

## 1.3.1 (30 Dec 2023)

### Fixes

* Fix downstream dialyzer error introduced by #86

## 1.3.0 (30 Dec 2023)

### Fixes

* Fix issue with eventual acceptor starvation when handling certain network
  conditions (#103)

### Enhancements

* Add check (and logging) for cases where a Handler implementation does not
  return the expected state from GenServer handle_* calls (#96, thanks
  @elfenlaid!)
* Allow protocol upgrades within an active connection (#86, thanks @icehaunter!)

### Changes

* Improve file list for hex packaging (#98, thanks @patrickjaberg and
  @wojtekmach!)

## 1.2.0 (11 Nov 2023)

### Enhancements

* Add `supervisor_options` option to specify top-level supervisor options (#97)

## 1.1.0 (23 Oct 2023)

### Enhancements

* Add support for `silent_terminate_on_error` option to run quietly in case of
  error (#92)

## 1.0.0 (18 Oct 2023)

### Changes

* Do not consider `ECONNABORTED` errors to be exceptional at socket start time
  (#72, thanks @dch!)

## 1.0.0-pre.7 (12 Aug 2023)

### Fixes

* Fix file handle leak when calling `c:Socket.sendfile` (#78)

## 1.0.0-pre.6 (28 Jun 2023)

### Enhancements

* Add support for suspending the acceptance of new requests while continuing to
  process existing ones (#70)

### Changes

* Drop Elixir 1.12 as a supported target (it should continue to work, but is no
  longer covered by CI)

## 1.0.0-pre.5 (16 Jun 2023)

### Changes

* **BREAKING CHANGE** Refactor socket informational functions to mirror the
  underlying `:gen_tcp` and `:ssl` APIs (#76, thanks @asakura!). Details:
    * Add `ThousandIsland.Socket.sockname/1`
    * Add `ThousandIsland.Socket.peername/1`
    * Add `ThousandIsland.Socket.peercert/1`
    * Remove `ThousandIsland.Socket.local_info/1`
    * Remove `ThousandIsland.Socket.peer_info/1`
* Refactor telemetry (#65 thanks @asakura!)

## 1.0.0-pre.4 (13 Jun 2023)

### Enhancements

* Improve typespecs (thanks @asakura!)
* Clean up docs & various internal cleanups (thanks @asakura!)

## 1.0.0-pre.3 (2 Jun 2023)

### Enhancements

* Total overhaul of typespecs throughout the library (thanks @asakura!)
* Internal refactor of several ancillary functions (thanks @asakura!)

## 1.0.0-pre.2 (3 May 2023)

### Enhancements

* Doc improvements

## 1.0.0-pre.1 (19 Apr 2023)

### Changes

* None

## 0.6.7 (9 Apr 2023)

### Changes

* Thousand Island now sets its `id` field in its spec to be `{ThousandIsland, ref()}`
* `num_connections` defaults to 16384 connections per acceptor

### Enhancements

* Doc improvements

## 0.6.6 (7 Apr 2023)

### Enhancements

* Added `num_connections` parameter to specify the max number of concurrent
  connections allowed per acceptor
* Added `max_connections_retry_count` and `max_connections_retry_wait`
  parameters to configure how Thousand Island behaves when max connections are
  reached
* Added `[:thousand_island, :acceptor, :spawn_error]` telemetry event to track
  when max connections are reached
* Added max connection logging as part of the
  `ThousandIsland.Logger.attach_logger(:error)` level

### Changes

* Refactored connection startup logic to move some burden from acceptor to
  connection process

## 0.6.5 (27 Mar 2023)

### Changes

* Handshake errors no longer loudly crash the handler process
* `handle_error/3` documentation updated to explicitly mention handshake errors

## 0.6.4 (17 Mar 2023)

### Changes

* Modified telemetry event payloads to match the conventions espoused by
  `:telemetry.span/3`

## 0.6.3 (14 Mar 2023)

### Enhancements

* Added `shutdown_timeout` configuration parameter to configure how long to wait
  for existing connections to shutdown before forcibly killing them at shutdown

### Changes

* Default value for `num_acceptors` is now 100
* Default value for `read_timeout` is now 60000 ms

### Fixes

* Added missing documentation for read_timeout configuration parameter

## 0.6.2 (22 Feb 2023)

### Fixes

* Fixes a race condition at application shutdown that caused spurious acceptor
  crashes to litter the logs (#44). Thanks @danschultzer!


## 0.6.1 (19 Feb 2023)

### Changes

* Expose ThousandIsland.Telemetry.t() as a transparent type
* Pass telemetry errors in metadata rather than metrics
* Allow explicit passing of start times into telemetry spans

## 0.6.0 (4 Feb 2023)

### Enhancements

* (Re)introduce telemetry support as specified in the `ThousandIsland.Telemetry`
  module

# Changelog for 0.5.x

## 0.5.17 (31 Jan 2023)

### Enhancements

* Add `ThousandIsland.connection_pids/1` to enumerate connection processes

## 0.5.16 (21 Jan 2023)

### Enhancements

* Narrow internal pattern matches to enable Handlers to use their own socket calls (#39)

### Fixes

* Fix documentation typos

## 0.5.15 (10 Jan 2023)

### Enhancements

* Do not emit GenServer crash logs in connection timeout situations
* Doc updates