What's the biggest message hotdog can handle?

[rtyler]

rsyslog has the maxMessageSize global variable, which defaults to 8K, after which a message will be truncated from the input socket.

I wonder how long of a message I could send to hotdog, which doesn't use the same primitive C-style buffer allocation.. 🤔

[rtyler]

Testing with the following script

#!/usr/bin/env ruby

require 'json'
require 'socket'
require 'openssl'

host = 'localhost'
tcp_client = TCPSocket.new(host, 6514)
ssl_client = OpenSSL::SSL::SSLSocket.new(tcp_client)
ssl_client.hostname = host
ssl_client.connect

def format_syslog(buffer)
  '<13>1 2020-04-18T15:16:09.956153-07:00 coconut tyler - - [timeQuality tzKnown="1" isSynced="1" syncAccuracy="505061"] ' + buffer + "\n"
end

ssl_client.write format_syslog("#{'0' * 1024} 1024")
ssl_client.write format_syslog("#{'0' * 8192} 8192")
ssl_client.write format_syslog("#{'0' * (2 ** 15)} 32k")
ssl_client.write format_syslog("#{'0' * (2 ** 16)} 64k")
ssl_client.write format_syslog("#{'0' * (2 ** 17)} 128k")

ssl_client.sysclose
tcp_client.close

32K works fine, but the 64K line crashes 🌭 with:

thread 'async-std/executor' panicked at 'assertion failed: `(left == right)`
  left: `49152`,
 right: `0`', <::std::macros::panic macros>:5:6
stack backtrace:
   0: backtrace::backtrace::libunwind::trace
             at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.44/src/backtrace/libunwind.rs:86
   1: backtrace::backtrace::trace_unsynchronized
             at /cargo/registry/src/github.com-1ecc6299db9ec823/backtrace-0.3.44/src/backtrace/mod.rs:66
   2: std::sys_common::backtrace::_print_fmt
             at src/libstd/sys_common/backtrace.rs:78
   3: <std::sys_common::backtrace::_print::DisplayBacktrace as core::fmt::Display>::fmt
             at src/libstd/sys_common/backtrace.rs:59
   4: core::fmt::write
             at src/libcore/fmt/mod.rs:1063
   5: std::io::Write::write_fmt
             at src/libstd/io/mod.rs:1426
   6: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:62
   7: std::sys_common::backtrace::print
             at src/libstd/sys_common/backtrace.rs:49
   8: std::panicking::default_hook::{{closure}}
             at src/libstd/panicking.rs:204
   9: std::panicking::default_hook
             at src/libstd/panicking.rs:224
  10: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:470
  11: rust_begin_unwind
             at src/libstd/panicking.rs:378
  12: std::panicking::begin_panic_fmt
             at src/libstd/panicking.rs:332
  13: async_std::io::buf_read::lines::read_line_internal
             at ./<::std::macros::panic macros>:5
  14: <async_std::io::buf_read::lines::Lines<R> as futures_core::stream::Stream>::poll_next
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-std-1.5.0/src/io/buf_read/lines.rs:37
  15: <async_std::stream::stream::next::NextFuture<T> as core::future::future::Future>::poll
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-std-1.5.0/src/stream/stream/next.rs:17
  16: std::future::poll_with_tls_context
             at /rustc/8d69840ab92ea7f4d323420088dd8c9775f180cd/src/libstd/future.rs:102
  17: hotdog::connection::Connection::read_logs::{{closure}}
             at src/connection.rs:76
  18: <std::future::GenFuture<T> as core::future::future::Future>::poll
             at /rustc/8d69840ab92ea7f4d323420088dd8c9775f180cd/src/libstd/future.rs:44
  19: std::future::poll_with_tls_context
             at /rustc/8d69840ab92ea7f4d323420088dd8c9775f180cd/src/libstd/future.rs:102
  20: <hotdog::serve_tls::TlsServer as hotdog::serve::Server>::handle_connection::{{closure}}
             at src/serve_tls.rs:61
  21: <std::future::GenFuture<T> as core::future::future::Future>::poll
             at /rustc/8d69840ab92ea7f4d323420088dd8c9775f180cd/src/libstd/future.rs:44
  22: std::future::poll_with_tls_context
             at /rustc/8d69840ab92ea7f4d323420088dd8c9775f180cd/src/libstd/future.rs:102
  23: async_std::task::builder::Builder::spawn::{{closure}}
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-std-1.5.0/src/task/builder.rs:64
  24: <std::future::GenFuture<T> as core::future::future::Future>::poll
             at /rustc/8d69840ab92ea7f4d323420088dd8c9775f180cd/src/libstd/future.rs:44
  25: async_task::raw::RawTask<F,R,S,T>::run
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-task-1.3.1/src/raw.rs:505
  26: async_task::task::Task<T>::run
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-task-1.3.1/src/task.rs:239
  27: async_std::task::builder::Runnable::run::{{closure}}::{{closure}}
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-std-1.5.0/src/task/builder.rs:81
  28: async_std::utils::abort_on_panic
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-std-1.5.0/src/utils.rs:16
  29: async_std::task::builder::Runnable::run::{{closure}}
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-std-1.5.0/src/task/builder.rs:81
  30: async_std::task::task::Task::set_current::{{closure}}
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-std-1.5.0/src/task/task.rs:129
  31: std::thread::local::LocalKey<T>::try_with
             at /rustc/8d69840ab92ea7f4d323420088dd8c9775f180cd/src/libstd/thread/local.rs:262
  32: std::thread::local::LocalKey<T>::with
             at /rustc/8d69840ab92ea7f4d323420088dd8c9775f180cd/src/libstd/thread/local.rs:239
  33: async_std::task::task::Task::set_current
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-std-1.5.0/src/task/task.rs:124
  34: async_std::task::builder::Runnable::run
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-std-1.5.0/src/task/builder.rs:81
  35: async_std::task::executor::pool::main_loop
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-std-1.5.0/src/task/executor/pool.rs:114
  36: core::ops::function::FnOnce::call_once
             at /rustc/8d69840ab92ea7f4d323420088dd8c9775f180cd/src/libcore/ops/function.rs:232
  37: async_std::utils::abort_on_panic
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-std-1.5.0/src/utils.rs:16
  38: async_std::task::executor::pool::POOL::{{closure}}::{{closure}}
             at /home/tyler/.cargo/registry/src/github.com-1ecc6299db9ec823/async-std-1.5.0/src/task/executor/pool.rs:46
note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.

[rtyler]

Looks like this crash is only on debug builds