:nick used to swap client->username unconditionally, so two clients
could both end up named "alice" — and the subsequent :msg / :w
disambiguation would just hit whichever came first in g_room->clients.
Now the rename happens under wrlock with an explicit scan: if any
*other* client already owns that username, the change is refused with
Nickname 'alice' is already taken
If the requested name equals the current one, return a short
"Nickname unchanged" instead of broadcasting a no-op system message.
The room-lock-held scan is O(n) over current clients (n ≤ 64 by
default) and folds naturally into the existing wrlock, so there's no
new lock acquisition.
Move client_t I/O and lifecycle out of ssh_server.c into a dedicated
module. ssh_server.c is now down to the listening socket, host key
setup, ssh_server_init / ssh_server_start, and the accept loop.
Migrated to client.{c,h}:
- client_send, client_printf
- client_addref, client_release (and the ssh_session / ssh_channel /
channel_cb teardown that fires on the final release)
- client_install_channel_callbacks
- client_channel_window_change / _eof / _close (the post-bootstrap
callbacks that target the client_t)
The client_t struct definition stays in ssh_server.h so we don't have
to revisit every existing #include chain. bootstrap, commands, exec,
input, and tui pick up the new client.h alongside their existing
ssh_server.h include.
ssh_server.c shrinks from 402 to 249 lines (-153).
Final per-module size after PR2:
ssh_server.c 249 accept loop + ssh_server_init/start + host key
bootstrap.c 493 per-connection SSH handshake / auth / channel
client.c 162 client_t I/O + lifecycle + channel callbacks
input.c 637 username read + handle_key + main loop +
notify_mentions + idle timeout
commands.c 269 vim ':' command dispatcher
exec.c 453 SSH exec subcommand dispatcher
ratelimit.c 197 IP rate limit + connection counters
tui.c 614 screen rendering
chat_room.c 151 room + client list
message.c 350 message log load/save/search
utf8.c 250 UTF-8 width / validation
common.c 133 buffer_*, env_int, is_valid_username,
sanitize_terminal_size, tnt_state_*
main.c 109 process entry
Total: ~4 000 lines of C across 13 files, no file over 650 lines, every
file is single-purpose. Behaviour is preserved: the migrated code is
byte-for-byte identical.
Move the vim-mode `:` command dispatcher (`:list`, `:nick`, `:msg`,
`:last`, `:search`, `:mute-joins`, `:help`, `:clear`, `:q`, …) out of
ssh_server.c into a dedicated module.
New API (include/commands.h):
- commands_dispatch(client_t *) -- single entry point invoked from
handle_key when Enter is pressed in MODE_COMMAND.
ssh_server.c shrinks from 1769 to 1513 lines (-256).
Behaviour preserved: implementation is byte-for-byte the same.
