Adding upstream version 8.4.4.upstream/8.4.4upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 297 insertions, 0 deletions

diff --git a/lib/zlog.h b/lib/zlog.h
new file mode 100644
index 0000000..dcc0bf1
--- /dev/null
+++ b/lib/zlog.h
@@ -0,0 +1,297 @@
+/*
+ * Copyright (c) 2015-19  David Lamparter, for NetDEF, Inc.
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#ifndef _FRR_ZLOG_H
+#define _FRR_ZLOG_H
+
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <string.h>
+#include <syslog.h>
+#include <unistd.h>
+#include <sys/uio.h>
+
+#include <assert.h>
+
+#include "atomlist.h"
+#include "frrcu.h"
+#include "memory.h"
+#include "hook.h"
+#include "printfrr.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+DECLARE_MGROUP(LOG);
+
+extern char zlog_prefix[];
+extern size_t zlog_prefixsz;
+extern int zlog_tmpdirfd;
+extern int zlog_instance;
+extern const char *zlog_progname;
+
+struct xref_logmsg {
+	struct xref xref;
+
+	const char *fmtstring;
+	uint32_t priority;
+	uint32_t ec;
+	const char *args;
+};
+
+/* whether flag was added in config mode or enable mode */
+#define LOGMSG_FLAG_EPHEMERAL	(1 << 0)
+#define LOGMSG_FLAG_PERSISTENT	(1 << 1)
+
+struct xrefdata_logmsg {
+	struct xrefdata xrefdata;
+
+	uint8_t fl_print_bt;
+};
+
+/* These functions are set up to write to stdout/stderr without explicit
+ * initialization and/or before config load.  There is no need to call e.g.
+ * fprintf(stderr, ...) just because it's "too early" at startup.  Depending
+ * on context, it may still be the right thing to use fprintf though -- try to
+ * determine whether something is a log message or something else.
+ */
+
+extern void vzlogx(const struct xref_logmsg *xref, int prio,
+		   const char *fmt, va_list ap);
+#define vzlog(prio, ...) vzlogx(NULL, prio, __VA_ARGS__)
+
+PRINTFRR(2, 3)
+static inline void zlog(int prio, const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	vzlog(prio, fmt, ap);
+	va_end(ap);
+}
+
+PRINTFRR(2, 3)
+static inline void zlog_ref(const struct xref_logmsg *xref,
+			    const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	vzlogx(xref, xref->priority, fmt, ap);
+	va_end(ap);
+}
+
+#define _zlog_ecref(ec_, prio, msg, ...)                                       \
+	do {                                                                   \
+		static struct xrefdata_logmsg _xrefdata = {                    \
+			.xrefdata =                                            \
+				{                                              \
+					.xref = NULL,                          \
+					.uid = {},                             \
+					.hashstr = (msg),                      \
+					.hashu32 = {(prio), (ec_)},            \
+				},                                             \
+		};                                                             \
+		static const struct xref_logmsg _xref __attribute__(           \
+			(used)) = {                                            \
+			.xref = XREF_INIT(XREFT_LOGMSG, &_xrefdata.xrefdata,   \
+					  __func__),                           \
+			.fmtstring = (msg),                                    \
+			.priority = (prio),                                    \
+			.ec = (ec_),                                           \
+			.args = (#__VA_ARGS__),                                \
+		};                                                             \
+		XREF_LINK(_xref.xref);                                         \
+		zlog_ref(&_xref, (msg), ##__VA_ARGS__);                        \
+	} while (0)
+
+#define zlog_err(...)    _zlog_ecref(0, LOG_ERR, __VA_ARGS__)
+#define zlog_warn(...)   _zlog_ecref(0, LOG_WARNING, __VA_ARGS__)
+#define zlog_info(...)   _zlog_ecref(0, LOG_INFO, __VA_ARGS__)
+#define zlog_notice(...) _zlog_ecref(0, LOG_NOTICE, __VA_ARGS__)
+#define zlog_debug(...)  _zlog_ecref(0, LOG_DEBUG, __VA_ARGS__)
+
+#define flog_err(ferr_id, format, ...)                                         \
+	_zlog_ecref(ferr_id, LOG_ERR, format, ## __VA_ARGS__)
+#define flog_warn(ferr_id, format, ...)                                        \
+	_zlog_ecref(ferr_id, LOG_WARNING, format, ## __VA_ARGS__)
+
+#define flog_err_sys(ferr_id, format, ...)                                     \
+	_zlog_ecref(ferr_id, LOG_ERR, format, ## __VA_ARGS__)
+
+extern void zlog_sigsafe(const char *text, size_t len);
+
+/* extra priority value to disable a target without deleting it */
+#define ZLOG_DISABLED	(LOG_EMERG-1)
+
+/* zlog_msg encapsulates a particular logging call from somewhere in the code.
+ * The same struct is passed around to all zlog_targets.
+ *
+ * This is used to defer formatting the log message until it is actually
+ * requested by one of the targets.  If none of the targets needs the message
+ * formatted, the formatting call is avoided entirely.
+ *
+ * This struct is opaque / private to the core zlog code.  Logging targets
+ * should use zlog_msg_* functions to get text / timestamps / ... for a
+ * message.
+ */
+
+struct zlog_msg;
+
+extern int zlog_msg_prio(struct zlog_msg *msg);
+extern const struct xref_logmsg *zlog_msg_xref(struct zlog_msg *msg);
+
+/* text is NOT \0 terminated; instead there is a \n after textlen since the
+ * logging targets would jump extra hoops otherwise for a single byte.  (the
+ * \n is not included in textlen)
+ *
+ * calling this with NULL textlen is likely wrong.
+ * use  "%.*s", (int)textlen, text  when passing to printf-like functions
+ */
+extern const char *zlog_msg_text(struct zlog_msg *msg, size_t *textlen);
+
+extern void zlog_msg_args(struct zlog_msg *msg, size_t *hdrlen,
+			  size_t *n_argpos, const struct fmt_outpos **argpos);
+
+/* timestamp formatting control flags */
+
+/* sub-second digit count */
+#define ZLOG_TS_PREC		0xfU
+
+/* 8601:   0000-00-00T00:00:00Z      (if used with ZLOG_TS_UTC)
+ *         0000-00-00T00:00:00+00:00 (otherwise)
+ * Legacy: 0000/00/00 00:00:00       (no TZ indicated!)
+ */
+#define ZLOG_TS_ISO8601		(1 << 8)
+#define ZLOG_TS_LEGACY		(1 << 9)
+
+/* default is local time zone */
+#define ZLOG_TS_UTC		(1 << 10)
+
+struct timespec;
+
+extern size_t zlog_msg_ts(struct zlog_msg *msg, struct fbuf *out,
+			  uint32_t flags);
+extern void zlog_msg_tsraw(struct zlog_msg *msg, struct timespec *ts);
+
+/* "mmm dd hh:mm:ss" for RFC3164 syslog.  Only ZLOG_TS_UTC for flags. */
+extern size_t zlog_msg_ts_3164(struct zlog_msg *msg, struct fbuf *out,
+			       uint32_t flags);
+
+/* currently just returns the current PID/TID since we never write another
+ * thread's messages
+ */
+extern void zlog_msg_pid(struct zlog_msg *msg, intmax_t *pid, intmax_t *tid);
+
+/* This list & struct implements the actual logging targets.  It is accessed
+ * lock-free from all threads, and thus MUST only be changed atomically, i.e.
+ * RCU.
+ *
+ * Since there's no atomic replace, the replacement action is an add followed
+ * by a delete.  This means that during logging config changes, log messages
+ * may be duplicated in the log target that is being changed.  The old entry
+ * being changed MUST also at the very least not crash or do other stupid
+ * things.
+ *
+ * This list and struct are NOT related to config.  Logging config is kept
+ * separately, and results in creating appropriate zlog_target(s) to realize
+ * the config.  Log targets may also be created from varying sources, e.g.
+ * command line options, or VTY commands ("log monitor").
+ *
+ * struct zlog_target is intended to be embedded into a larger structure that
+ * contains additional field for the specific logging target, e.g. an fd or
+ * additional options.  It MUST be the first field in that larger struct.
+ */
+
+PREDECL_ATOMLIST(zlog_targets);
+struct zlog_target {
+	struct zlog_targets_item head;
+
+	int prio_min;
+
+	void (*logfn)(struct zlog_target *zt, struct zlog_msg *msg[],
+		      size_t nmsgs);
+
+	/* for crash handlers, set to NULL if log target can't write crash logs
+	 * without possibly deadlocking (AS-Safe)
+	 *
+	 * text is not \0 terminated & split up into lines (e.g. no \n)
+	 */
+	void (*logfn_sigsafe)(struct zlog_target *zt, const char *text,
+			      size_t len);
+
+	struct rcu_head rcu_head;
+};
+
+/* make a copy for RCUpdating.  oldzt may be NULL to allocate a fresh one. */
+extern struct zlog_target *zlog_target_clone(struct memtype *mt,
+					     struct zlog_target *oldzt,
+					     size_t size);
+
+/* update the zlog_targets list;  both oldzt and newzt may be NULL.  You
+ * still need to zlog_target_free() the old target afterwards if it wasn't
+ * NULL.
+ *
+ * Returns oldzt so you can zlog_target_free(zlog_target_replace(old, new));
+ * (Some log targets may need extra cleanup inbetween, but remember the old
+ * target MUST remain functional until the end of the current RCU cycle.)
+ */
+extern struct zlog_target *zlog_target_replace(struct zlog_target *oldzt,
+					       struct zlog_target *newzt);
+
+/* Mostly for symmetry for zlog_target_clone(), just rcu_free() internally. */
+#define zlog_target_free(mt, zt) \
+	rcu_free(mt, zt, rcu_head)
+
+extern void zlog_init(const char *progname, const char *protoname,
+		      unsigned short instance, uid_t uid, gid_t gid);
+DECLARE_HOOK(zlog_init, (const char *progname, const char *protoname,
+			 unsigned short instance, uid_t uid, gid_t gid),
+			(progname, protoname, instance, uid, gid));
+
+extern void zlog_fini(void);
+DECLARE_KOOH(zlog_fini, (), ());
+
+extern void zlog_set_prefix_ec(bool enable);
+extern bool zlog_get_prefix_ec(void);
+extern void zlog_set_prefix_xid(bool enable);
+extern bool zlog_get_prefix_xid(void);
+
+/* for tools & test programs, i.e. anything not a daemon.
+ * (no cleanup needed at exit)
+ */
+extern void zlog_aux_init(const char *prefix, int prio_min);
+DECLARE_HOOK(zlog_aux_init, (const char *prefix, int prio_min),
+			    (prefix, prio_min));
+
+extern void zlog_startup_end(void);
+
+extern void zlog_tls_buffer_init(void);
+extern void zlog_tls_buffer_flush(void);
+extern void zlog_tls_buffer_fini(void);
+
+/* Enable or disable 'immediate' output - default is to buffer messages. */
+extern void zlog_set_immediate(bool set_p);
+
+extern const char *zlog_priority_str(int priority);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _FRR_ZLOG_H */