Add structured JSON event stream and exit codes

New --json-events flag emits JSON on stderr for GUI integration.
exit_codes.h defines specific codes for each failure type.

Author: hkirste

src/event.c

@@ -0,0 +1,120 @@
+/*
+ *  Copyright (c) 2015 Adrien Vergé
+ *
+ *  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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "event.h"
+
+#include <pthread.h>
+
+#include <stdarg.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+#include <time.h>
+
+static int events_enabled;
+static int64_t seq_counter;
+static pthread_mutex_t event_mutex = PTHREAD_MUTEX_INITIALIZER;
+
+void event_init(int enabled)
+{
+	events_enabled = enabled;
+}
+
+void event_emit(const char *type, const char *json_fields_fmt, ...)
+{
+	va_list ap;
+	char fields_buf[2048];
+
+	if (!events_enabled)
+		return;
+
+	pthread_mutex_lock(&event_mutex);
+
+	fprintf(stderr, "{\"event\":\"%s\",\"ts\":%lld,\"seq\":%lld",
+	        type, (long long)time(NULL), (long long)seq_counter++);
+
+	if (json_fields_fmt && json_fields_fmt[0] != '\0') {
+		va_start(ap, json_fields_fmt);
+		vsnprintf(fields_buf, sizeof(fields_buf), json_fields_fmt, ap);
+		va_end(ap);
+		fprintf(stderr, ",%s", fields_buf);
+	}
+
+	fprintf(stderr, "}\n");
+	fflush(stderr);
+
+	pthread_mutex_unlock(&event_mutex);
+}
+
+char *json_escape(char *buf, size_t buf_size, const char *input)
+{
+	size_t i = 0;
+	size_t o = 0;
+
+	if (!buf || buf_size == 0)
+		return buf;
+
+	/* Reserve space for NUL terminator */
+	buf_size--;
+
+	if (!input) {
+		buf[0] = '\0';
+		return buf;
+	}
+
+	while (input[i] != '\0' && o < buf_size) {
+		unsigned char c = (unsigned char)input[i];
+
+		if (c == '"') {
+			if (o + 2 > buf_size)
+				break;
+			buf[o++] = '\\';
+			buf[o++] = '"';
+		} else if (c == '\\') {
+			if (o + 2 > buf_size)
+				break;
+			buf[o++] = '\\';
+			buf[o++] = '\\';
+		} else if (c == '\n') {
+			if (o + 2 > buf_size)
+				break;
+			buf[o++] = '\\';
+			buf[o++] = 'n';
+		} else if (c == '\r') {
+			if (o + 2 > buf_size)
+				break;
+			buf[o++] = '\\';
+			buf[o++] = 'r';
+		} else if (c == '\t') {
+			if (o + 2 > buf_size)
+				break;
+			buf[o++] = '\\';
+			buf[o++] = 't';
+		} else if (c < 0x20) {
+			if (o + 6 > buf_size)
+				break;
+			snprintf(buf + o, 7, "\\u%04x", c);
+			o += 6;
+		} else {
+			buf[o++] = c;
+		}
+		i++;
+	}
+
+	buf[o] = '\0';
+	return buf;
+}

src/event.h

@@ -0,0 +1,35 @@
+/*
+ *  Copyright (c) 2015 Adrien Vergé
+ *
+ *  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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef OPENFORTIVPN_EVENT_H
+#define OPENFORTIVPN_EVENT_H
+
+#include <stddef.h>
+
+/* Initialize the event system. enabled=1 turns on JSON output to stderr. */
+void event_init(int enabled);
+
+/* Emit a JSON event line to stderr. fmt contains key:value pairs in JSON. */
+void event_emit(const char *type, const char *json_fields_fmt, ...);
+
+/*
+ * Helper: escape a string for JSON (handles quotes, backslashes, control chars).
+ * Writes to buf, returns buf. Truncates if output exceeds buf_size.
+ */
+char *json_escape(char *buf, size_t buf_size, const char *input);
+
+#endif /* OPENFORTIVPN_EVENT_H */

src/exit_codes.h

@@ -0,0 +1,39 @@
+/*
+ *  Copyright (c) 2015 Adrien Vergé
+ *
+ *  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 3 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, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef OPENFORTIVPN_EXIT_CODES_H
+#define OPENFORTIVPN_EXIT_CODES_H
+
+enum ofv_exit_code {
+	OFV_EXIT_OK             = 0,
+	OFV_EXIT_GENERIC        = 1,   /* legacy fallback */
+	OFV_EXIT_DNS_FAILED     = 10,
+	OFV_EXIT_TCP_FAILED     = 11,
+	OFV_EXIT_TLS_FAILED     = 12,
+	OFV_EXIT_CERT_FAILED    = 13,
+	OFV_EXIT_AUTH_FAILED    = 20,
+	OFV_EXIT_OTP_MISSING    = 21,
+	OFV_EXIT_SAML_FAILED    = 22,
+	OFV_EXIT_ALLOC_DENIED   = 23,
+	OFV_EXIT_CONFIG_FAILED  = 30,
+	OFV_EXIT_ADAPTER_FAILED = 40,
+	OFV_EXIT_TUNNEL_FAILED  = 41,
+	OFV_EXIT_PERMISSION     = 50,
+	OFV_EXIT_SIGNAL         = 60
+};
+
+#endif /* OPENFORTIVPN_EXIT_CODES_H */