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, 1 insertions, 2 deletions

diff --git a/bgpd/rfapi/rfapi_vty.c b/bgpd/rfapi/rfapi_vty.c
index 5a84d14bd..0d4868fa5 100644
--- a/bgpd/rfapi/rfapi_vty.c
+++ b/bgpd/rfapi/rfapi_vty.c
@@ -25,7 +25,6 @@
 #include "lib/memory.h"
 #include "lib/routemap.h"
 #include "lib/log.h"
-#include "lib/log_int.h"
 #include "lib/linklist.h"
 #include "lib/command.h"
 
@@ -371,7 +370,7 @@ int rfapiStream2Vty(void *stream,			   /* input */
 		*fp = (int (*)(void *, const char *, ...))rfapiDebugPrintf;
 		*outstream = NULL;
 		*vty_newline = str_vty_newline(*vty);
-		return (vzlog_test(LOG_DEBUG));
+		return 1;
 	}
 
 	if (((uintptr_t)stream == (uintptr_t)1)