stats-json: fixes and improvements

Use proper LogFileCtx and MemBuffer handling so we can have multiple
loggers active at the same time.

Change 'date' field to timestamp, and use ISO notation to make it
the same as the other JSON outputs.

src/output-json-stats.c

@@ -56,14 +56,11 @@ typedef struct OutputStatsCtx_ {
     uint32_t flags; /** Store mode */
 } OutputStatsCtx;
 
-
 typedef struct JsonStatsLogThread_ {
     OutputStatsCtx *statslog_ctx;
+    MemBuffer *buffer;
 } JsonStatsLogThread;
 
-static void *eve_file_ctx = NULL;
-static void *eve_buffer = NULL;
-
 static
 json_t *SCPerfLookupJson(json_t *js, char *key)
 {
@@ -85,17 +82,14 @@ json_t *SCPerfLookupJson(json_t *js, char *key)
     return value;
 }
 
-static int JsonStatsLogger(ThreadVars *tv, void *thread_data, StatsTable *st)
+static int JsonStatsLogger(ThreadVars *tv, void *thread_data, const StatsTable *st)
 {
     SCEnter();
-    /*JsonStatsLogThread *aft = (JsonStatsLogThread *)thread_data; */
+    JsonStatsLogThread *aft = (JsonStatsLogThread *)thread_data;
+    MemBuffer *buffer = (MemBuffer *)aft->buffer;
 
     struct timeval tval;
-    struct tm *tms;
-
     gettimeofday(&tval, NULL);
-    struct tm local_tm;
-    tms = SCLocalTime(tval.tv_sec, &local_tm);
 
     /* Calculate the Engine uptime */
     int up_time = (int)difftime(tval.tv_sec, st->start_time);
@@ -110,19 +104,16 @@ static int JsonStatsLogger(ThreadVars *tv, void *thread_data, StatsTable *st)
     if (unlikely(js == NULL))
         return 0;
 
+    char timebuf[64];
+    CreateIsoTimeString(&tval, timebuf, sizeof(timebuf));
+    json_object_set_new(js, "timestamp", json_string(timebuf));
+
     json_object_set_new(js, "event_type", json_string("stats"));
     json_t *js_stats = json_object();
     if (unlikely(js_stats == NULL)) {
         json_decref(js);
         return 0;
     }
-    char date[128];
-    snprintf(date, sizeof(date),
-             "%" PRId32 "/%" PRId32 "/%04d -- %02d:%02d:%02d",
-             tms->tm_mon + 1, tms->tm_mday, tms->tm_year + 1900, tms->tm_hour,
-             tms->tm_min, tms->tm_sec);
-
-    json_object_set_new(js_stats, "date", json_string(date));
 
     char uptime[128];
     snprintf(uptime, sizeof(uptime),
@@ -144,9 +135,9 @@ static int JsonStatsLogger(ThreadVars *tv, void *thread_data, StatsTable *st)
     }
     json_object_set_new(js, "stats", js_stats);
 
-    if (eve_file_ctx != NULL && eve_buffer != NULL) {
-        OutputJSONBuffer(js, eve_file_ctx, eve_buffer);
-    }
+    OutputJSONBuffer(js, aft->statslog_ctx->file_ctx, buffer);
+    MemBufferReset(buffer);
+
     json_object_clear(js);
     json_decref(js);
 
@@ -171,6 +162,12 @@ static TmEcode JsonStatsLogThreadInit(ThreadVars *t, void *initdata, void **data
     /* Use the Ouptut Context (file pointer and mutex) */
     aft->statslog_ctx = ((OutputCtx *)initdata)->data;
 
+    aft->buffer = MemBufferCreateNew(OUTPUT_BUFFER_SIZE);
+    if (aft->buffer == NULL) {
+        SCFree(aft);
+        return TM_ECODE_FAILED;
+    }
+
     *data = (void *)aft;
     return TM_ECODE_OK;
 }
@@ -182,6 +179,8 @@ static TmEcode JsonStatsLogThreadDeinit(ThreadVars *t, void *data)
         return TM_ECODE_OK;
     }
 
+    MemBufferFree(aft->buffer);
+
     /* clear memory */
     memset(aft, 0, sizeof(JsonStatsLogThread));
 
@@ -236,7 +235,6 @@ OutputCtx *OutputStatsLogInit(ConfNode *conf)
 
 static void OutputStatsLogDeinitSub(OutputCtx *output_ctx)
 {
-
     OutputStatsCtx *stats_ctx = output_ctx->data;
     SCFree(stats_ctx);
     SCFree(output_ctx);
@@ -245,7 +243,6 @@ static void OutputStatsLogDeinitSub(OutputCtx *output_ctx)
 OutputCtx *OutputStatsLogInitSub(ConfNode *conf, OutputCtx *parent_ctx)
 {
     AlertJsonThread *ajt = parent_ctx->data;
-    MemBuffer *buffer;
 
     OutputStatsCtx *stats_ctx = SCMalloc(sizeof(OutputStatsCtx));
     if (unlikely(stats_ctx == NULL))
@@ -262,16 +259,6 @@ OutputCtx *OutputStatsLogInitSub(ConfNode *conf, OutputCtx *parent_ctx)
     output_ctx->data = stats_ctx;
     output_ctx->DeInit = OutputStatsLogDeinitSub;
 
-    buffer = MemBufferCreateNew(OUTPUT_BUFFER_SIZE);
-    if (buffer == NULL) {
-        SCFree(stats_ctx);
-        SCFree(output_ctx);
-        return NULL;
-    }
-
-    eve_file_ctx = stats_ctx->file_ctx;
-    eve_buffer = buffer;
-
     return output_ctx;
 }
 
@@ -284,7 +271,7 @@ void TmModuleJsonStatsLogRegister (void) {
     tmm_modules[TMM_JSONSTATSLOG].flags = TM_FLAG_LOGAPI_TM;
 
     /* register as separate module */
-    OutputRegisterStatsModule(MODULE_NAME, "stats", OutputStatsLogInit,
+    OutputRegisterStatsModule(MODULE_NAME, "stats-json", OutputStatsLogInit,
                               JsonStatsLogger);
 
     /* also register as child of eve-log */