path: root/src/server/rpc.c

#include "rpc.h"
#include "helper.h"
#include "net.h"
#include "uplink.h"
#include "locks.h"
#include "image.h"
#include "../shared/sockhelper.h"

static void clientsToJson(json_t *jsonClients);

void rpc_sendStatsJson(int sock)
{
	json_t *jsonClients = json_array();
	clientsToJson( jsonClients );
	const uint64_t bytesReceived = uplink_getTotalBytesReceived();
	const uint64_t bytesSent = net_getTotalBytesSent();
	const int uptime = dnbd3_serverUptime();

	json_t *statisticsJson = json_pack( "{sIsI}",
			"bytesReceived", (json_int_t) bytesReceived,
			"bytesSent", (json_int_t) bytesSent );
	json_object_set_new( statisticsJson, "clients", jsonClients );
	json_object_set_new( statisticsJson, "images", image_getListAsJson() );
	json_object_set_new( statisticsJson, "uptime", json_integer( uptime ) );
	char *jsonString = json_dumps( statisticsJson, 0 );
	json_decref( statisticsJson );

	char buffer[500];
	snprintf(buffer, sizeof buffer , "HTTP/1.1 200 OK\r\n"
			"Connection: Close\r\n"
			"Content-Length: %d\r\n"
			"Content-Type: application/json\r\n"
			"\r\n",
			(int) strlen( jsonString ) );
	write( sock, buffer, strlen( buffer ) );
	sock_sendAll( sock, jsonString, strlen( jsonString ), 10 );
	// Wait for flush
	shutdown( sock, SHUT_WR );
	while ( read( sock, buffer, sizeof buffer ) > 0 );
	free( jsonString );
}

static void clientsToJson(json_t *jsonClients)
{
	json_t *clientStats;
	int i;
	int imgId;
	uint64_t bytesSent;
	char host[HOSTNAMELEN];
	host[HOSTNAMELEN-1] = '\0';

	spin_lock( &_clients_lock );
	for ( i = 0; i < _num_clients; ++i ) {
		if ( _clients[i] == NULL ) {
			continue;
		}
		dnbd3_client_t * const client = _clients[i];
		spin_lock( &client->lock );
		spin_unlock( &_clients_lock );
		// Unlock so we give other threads a chance to access the client list.
		// We might not get an atomic snapshot of the currently connected clients,
		// but that doesn't really make a difference anyways.
		if ( client->image == NULL ) {
			spin_unlock( &client->lock );
			imgId = -1;
		} else {
			strncpy( host, client->hostName, HOSTNAMELEN - 1 );
			imgId = client->image->id;
			spin_lock( &client->statsLock );
			spin_unlock( &client->lock );
			bytesSent = client->bytesSent;
			net_updateGlobalSentStatsFromClient( client ); // Do this since we read the totalBytesSent counter later
			spin_unlock( &client->statsLock );
		}
		if ( imgId != -1 ) {
			clientStats = json_pack( "{sssisI}",
					"address", host,
					"imageId", imgId,
					"bytesSent", (json_int_t)bytesSent );
			json_array_append_new( jsonClients, clientStats );
		}
		spin_lock( &_clients_lock );
	}
	spin_unlock( &_clients_lock );
}