Implement GSMTAP log target
This target wraps the to-be-logged string (With metadata) into a GSMTAP
packet and sends it to the configured destination address.
Change-Id: I9a7e72b8c9c6f6f2d76d1ea2332dcdee12394625
diff --git a/src/logging_gsmtap.c b/src/logging_gsmtap.c
new file mode 100644
index 0000000..85f8c28
--- /dev/null
+++ b/src/logging_gsmtap.c
@@ -0,0 +1,134 @@
+/* GSMTAP network logging support code */
+
+/* (C) 2016 by Harald Welte <laforge@gnumonks.org>
+ * All Rights Reserved
+ *
+ * This program 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 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ */
+
+/*! \addtogroup logging
+ * @{
+ */
+
+/*! \file logging_gsmtap.c */
+
+#include "../config.h"
+
+#include <stdarg.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdbool.h>
+#include <arpa/inet.h>
+
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
+
+#include <osmocom/core/talloc.h>
+#include <osmocom/core/utils.h>
+#include <osmocom/core/gsmtap.h>
+#include <osmocom/core/gsmtap_util.h>
+#include <osmocom/core/logging.h>
+#include <osmocom/core/timer.h>
+
+#define GSMTAP_LOG_MAX_SIZE 4096
+
+static void _gsmtap_raw_output(struct log_target *target, int subsys,
+ unsigned int level, const char *file,
+ int line, int cont, const char *format,
+ va_list ap)
+{
+ struct msgb *msg;
+ struct gsmtap_hdr *gh;
+ struct gsmtap_osmocore_log_hdr *golh;
+ const char *subsys_name = log_category_name(subsys);
+ struct timeval tv;
+ int rc;
+
+ /* get timestamp ASAP */
+ osmo_gettimeofday(&tv, NULL);
+
+ msg = msgb_alloc(sizeof(*gh)+sizeof(*golh)+GSMTAP_LOG_MAX_SIZE,
+ "GSMTAP logging");
+
+ /* GSMTAP header */
+ gh = (struct gsmtap_hdr *) msgb_put(msg, sizeof(*gh));
+ memset(gh, 0, sizeof(*gh));
+ gh->version = GSMTAP_VERSION;
+ gh->hdr_len = sizeof(*gh)/4;
+ gh->type = GSMTAP_TYPE_OSMOCORE_LOG;
+
+ /* Logging header */
+ golh = (struct gsmtap_osmocore_log_hdr *) msgb_put(msg, sizeof(*golh));
+ osmo_strlcpy(golh->proc_name, target->tgt_gsmtap.ident,
+ sizeof(golh->proc_name));
+ if (subsys_name)
+ osmo_strlcpy(golh->subsys, subsys_name+1, sizeof(golh->subsys));
+ else
+ golh->subsys[0] = '\0';
+ osmo_strlcpy(golh->src_file.name, file, sizeof(golh->src_file.name));
+ golh->src_file.line_nr = htonl(line);
+ golh->level = level;
+ /* we always store the timestamp in the message, irrespective
+ * of hat prrint_[ext_]timestamp say */
+ golh->ts.sec = htonl(tv.tv_sec);
+ golh->ts.usec = htonl(tv.tv_usec);
+
+ rc = vsnprintf((char *) msg->tail, msgb_tailroom(msg), format, ap);
+ if (rc < 0)
+ return;
+ msgb_put(msg, rc);
+
+ gsmtap_sendmsg(target->tgt_gsmtap.gsmtap_inst, msg);
+}
+
+/*! \brief Create a new logging target for GSMTAP logging
+ * \param[in] ident string identifier
+ * \returns Log target in case of success, NULL in case of error
+ */
+struct log_target *log_target_create_gsmtap(const char *host, uint16_t port,
+ const char *ident,
+ bool ofd_wq_mode,
+ bool add_sink)
+{
+ struct log_target *target;
+ struct gsmtap_inst *gti;
+
+ target = log_target_create();
+ if (!target)
+ return NULL;
+
+ gti = gsmtap_source_init(host, port, ofd_wq_mode);
+ if (!gti) {
+ log_target_destroy(target);
+ return NULL;
+ }
+
+ if (add_sink)
+ gsmtap_source_add_sink(gti);
+
+ target->tgt_gsmtap.gsmtap_inst = gti;
+ target->tgt_gsmtap.ident = talloc_strdup(target, ident);
+ target->tgt_gsmtap.hostname = talloc_strdup(target, host);
+
+ target->type = LOG_TGT_TYPE_GSMTAP;
+ target->raw_output = _gsmtap_raw_output;
+
+ return target;
+}
+
+/* @} */