lib: rewrite zlog lock-free & TLS-buffered

This is a full rewrite of the "back end" logging code.  It now uses a
lock-free list to iterate over logging targets, and the targets
themselves are as lock-free as possible.  (syslog() may have a hidden
internal mutex in the C library;  the file/fd targets use a single
write() call which should ensure atomicity kernel-side.)

Note that some functionality is lost in this patch:
- Solaris printstack() backtraces are ditched (unlikely to come back)
- the `log-filter` machinery is gone (re-added in followup commit)
- `terminal monitor` is temporarily stubbed out.  The old code had a
  race condition with VTYs going away.  It'll likely come back rewritten
  and with vtysh support.
- The `zebra_ext_log` hook is gone.  Instead, it's now much easier to
  add a "proper" logging target.

v2: TLS buffer to get some actual performance

Signed-off-by: David Lamparter <equinox@diac24.net>

1 files changed, 0 insertions, 59 deletions

diff --git a/lib/log_int.h b/lib/log_int.h
deleted file mode 100644
index 287e626eab..0000000000
--- a/lib/log_int.h
+++ /dev/null
@@ -1,59 +0,0 @@
-/*
- * Zebra logging funcions.
- * Copyright (C) 1997, 1998, 1999 Kunihiro Ishiguro
- *
- * This file is part of GNU Zebra.
- *
- * GNU Zebra is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the
- * Free Software Foundation; either version 2, or (at your option) any
- * later version.
- *
- * GNU Zebra is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; see the file COPYING; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
- */
-
-#ifndef _ZEBRA_LOG_PRIVATE_H
-#define _ZEBRA_LOG_PRIVATE_H
-
-#include "log.h"
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-struct zlog {
-	const char *ident; /* daemon name (first arg to openlog) */
-	const char *protoname;
-	unsigned short instance;
-	int maxlvl[ZLOG_NUM_DESTS]; /* maximum priority to send to associated
-				       logging destination */
-	int default_lvl;	    /* maxlvl to use if none is specified */
-	FILE *fp;
-	char *filename;
-	int facility;	/* as per syslog facility */
-	int record_priority; /* should messages logged through stdio include the
-				priority of the message? */
-	int syslog_options;  /* 2nd arg to openlog */
-	int timestamp_precision; /* # of digits of subsecond precision */
-};
-
-/* Default logging strucutre. */
-extern struct zlog *zlog_default;
-
-extern const char *zlog_priority[];
-
-/* Generic function for zlog. */
-extern void vzlog(int priority, const char *format, va_list args);
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif /* _ZEBRA_LOG_PRIVATE_H */