Once 3proxy runs (after the first configuration is in force, so after a
daemon's fork), each logger has a thread of its own writing from a
queue, and a client never waits for a log: ODBC, RADIUS, a full disk or
a pipe nobody reads hold up only that log's thread.
A queued line is fixed size: the part of struct clientparam logging
reads (everything before the filters: addresses, counters, names and
credentials, which hold no pointer it follows but srv), the time it was
logged, and its text, 256 bytes inline or a copy of its own if longer.
The thread formats it: struct tm is per call now, timechanged() and
dologname() included, and the type's format() takes the time.
minlogqueue (64) slots are allocated as the thread starts and kept,
maxlogqueue (4096) lines are queued at most. A line which finds the
queue full is dropped and counted on the last one queued; once that is
written, "Log X has its queue full, N records dropped" goes to where
errors go. A log which fails is no longer written to the error log
instead: its lines are dropped and counted while it is retried every
minute, and the count is told when it is open again, or when it was
reopened after failed writes.
A service which ended is stopped at once (srvstop(): sockets, listener,
its clients gone), but freed (srvrelease()) through its log's queue,
behind the lines which refer to it and to its configuration: the event
is part of struct srvparam, so a full queue never drops it. logfinish()
writes what is queued, 10 seconds at most, also as 3proxy exits on Unix.
Standalone services write as before, as each line comes.
LOGQUEUEMIN, LOGQUEUEMAX, DEFAULT_MAXCHILD, DEFAULT_POOLMAX,
DEFAULT_POOLTIMEOUT and POOLPERSERVICE (the automatic thread pool cap
for each service, which was 32 in the code) can be set with -D at build
time.
Tests: a log nobody reads (a FIFO) holds no client up, drops past its
queue and says so, and lines queued for a service a reload removed are
written as it formatted them; /dev/full says what it dropped.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A logger (struct logger) is identified by the string log or -l gives it:
"" stdout, "/dev/null" none, "@IDENT" syslog, "&DSN" ODBC, "radius",
anything else a file. Each type (struct logtype) has init, formatting of
a connection into a buffer, writing, close, and a periodic tick for
rotation and flushing; ODBC and RADIUS register their types from 3proxy,
which alone has them. Services and configurations hold the logger they
use; the last to let go closes it, except the standard ones (none,
stdout, stderr, syslog), which are opened at startup and kept.
-l takes every log type now, and a file named by several services or by
both log and -l is opened once. rotate and archiver are bound to the
logger of the last log command when its configuration comes into force,
and every file logger is rotated by the main loop.
Errors with no connection go to a new stderr logger; after daemon, or as
a Windows service, stdout logging writes nothing and errors go to the
last log configured. A log whose writes keep failing is closed and
reopened; while it cannot be, its lines go to stderr and it is retried
every minute. ODBC's own reconnection throttle gives way to this.
Formatting (logbuf) is separate from counting traffic and clearing the
statistics, done once by logdo(), the services' log function, so a later
step can format or copy a connection's line and write it from a thread
of its own. dologname() and timechanged() move to log.c, which the
standalone services link as well.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
