* Author : Maxim Mamontov <faust@stargazer.dp.ua>
*/
-/*
- $Revision: 1.33 $
- $Date: 2010/04/16 12:30:37 $
- $Author: faust $
-*/
-
#include <sys/time.h>
#include <csignal>
#include <cassert>
+#include <cstdlib>
+#include <cerrno>
+#include <cstring>
#include <algorithm>
#include "stg/common.h"
-#include "stg/stg_locker.h"
+#include "stg/locker.h"
+#include "stg/users.h"
#include "stg/user_property.h"
+#include "stg/plugin_creator.h"
+#include "stg/logger.h"
#include "rscript.h"
#include "ur_functor.h"
#include "send_functor.h"
-extern volatile const time_t stgTime;
+extern volatile time_t stgTime;
-#define RS_MAX_ROUTERS (100)
+using RS::REMOTE_SCRIPT;
-//-----------------------------------------------------------------------------
-//-----------------------------------------------------------------------------
-//-----------------------------------------------------------------------------
-class RS_CREATOR
-{
-private:
- REMOTE_SCRIPT * rs;
+namespace {
-public:
- RS_CREATOR()
- : rs(new REMOTE_SCRIPT())
- {
- };
- ~RS_CREATOR()
- {
- delete rs;
- };
+template<typename T>
+struct USER_IS
+{
+ USER_IS(USER_PTR u) : user(u) {}
+ bool operator()(const T & notifier) { return notifier.GetUser() == user; }
- REMOTE_SCRIPT * GetPlugin()
- {
- return rs;
- };
+ USER_PTR user;
};
+
+PLUGIN_CREATOR<REMOTE_SCRIPT> rsc;
+
+} // namespace anonymous
+
+extern "C" PLUGIN * GetPlugin();
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
-RS_CREATOR rsc;
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
-RS_USER::RS_USER()
- : lastSentTime(0),
- user(NULL),
- shortPacketsCount(0)
-{
-}
-//-----------------------------------------------------------------------------
-RS_USER::RS_USER(const std::vector<uint32_t> & r, USER_PTR it)
- : lastSentTime(0),
- user(it),
- routers(r),
- shortPacketsCount(0)
-{
-}
-//-----------------------------------------------------------------------------
-RS_SETTINGS::RS_SETTINGS()
+RS::SETTINGS::SETTINGS()
: sendPeriod(0),
- port(0)
+ port(0),
+ errorStr(),
+ netRouters(),
+ userParams(),
+ password(),
+ subnetFile()
{
}
//-----------------------------------------------------------------------------
-int RS_SETTINGS::ParseIntInRange(const string & str, int min, int max, int * val)
-{
-if (str2x(str.c_str(), *val))
- {
- errorStr = "Incorrect value \'" + str + "\'.";
- return -1;
- }
-if (*val < min || *val > max)
- {
- errorStr = "Value \'" + str + "\' out of range.";
- return -1;
- }
-return 0;
-}
-//-----------------------------------------------------------------------------
-int RS_SETTINGS::ParseSettings(const MODULE_SETTINGS & s)
+int RS::SETTINGS::ParseSettings(const MODULE_SETTINGS & s)
{
int p;
PARAM_VALUE pv;
-vector<PARAM_VALUE>::const_iterator pvi;
+
std::vector<PARAM_VALUE>::const_iterator pvi;
netRouters.clear();
///////////////////////////
pv.param = "Port";
printfd(__FILE__, "Cannot parse parameter 'Port'\n");
return -1;
}
-port = p;
+port = static_cast<uint16_t>(p);
///////////////////////////
pv.param = "SendPeriod";
pvi = find(s.moduleParams.begin(), s.moduleParams.end(), pv);
NRMapParser nrMapParser;
-if (nrMapParser.ReadFile(subnetFile))
+if (!nrMapParser.ReadFile(subnetFile))
{
- errorStr = nrMapParser.GetErrorStr();
- return -1;
+ netRouters = nrMapParser.GetMap();
}
-
-netRouters = nrMapParser.GetMap();
-
-if (netRouters.empty())
+else
{
- errorStr = "Parameter(s) \'Subnet*\' not found.";
- printfd(__FILE__, "Parameter(s) 'Subnet*' not found\n");
- return -1;
+ GetStgLogger()("mod_rscript: error opening subnets file '%s'", subnetFile.c_str());
}
return 0;
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
REMOTE_SCRIPT::REMOTE_SCRIPT()
- : sendPeriod(15),
+ : ctx(),
+ ipNotifierList(),
+ connNotifierList(),
+ authorizedUsers(),
+ errorStr(),
+ rsSettings(),
+ settings(),
+ sendPeriod(15),
halfPeriod(8),
nonstop(false),
isRunning(false),
users(NULL),
+ netRouters(),
+ thread(),
+ mutex(),
sock(0),
onAddUserNotifier(*this),
- onDelUserNotifier(*this)
+ onDelUserNotifier(*this),
+ logger(GetPluginLogger(GetStgLogger(), "rscript"))
{
pthread_mutex_init(&mutex, NULL);
}
//-----------------------------------------------------------------------------
void * REMOTE_SCRIPT::Run(void * d)
{
+sigset_t signalSet;
+sigfillset(&signalSet);
+pthread_sigmask(SIG_BLOCK, &signalSet, NULL);
+
REMOTE_SCRIPT * rs = static_cast<REMOTE_SCRIPT *>(d);
rs->isRunning = true;
InitEncrypt(&ctx, rsSettings.GetPassword());
-//onAddUserNotifier.SetRemoteScript(this);
-//onDelUserNotifier.SetRemoteScript(this);
-
users->AddNotifierUserAdd(&onAddUserNotifier);
users->AddNotifierUserDel(&onDelUserNotifier);
if (pthread_create(&thread, NULL, Run, this))
{
errorStr = "Cannot create thread.";
+ logger("Cannot create thread.");
printfd(__FILE__, "Cannot create thread\n");
return -1;
}
//5 seconds to thread stops itself
for (int i = 0; i < 25 && isRunning; i++)
{
- usleep(200000);
- }
-
- //after 5 seconds waiting thread still running. now killing it
- if (isRunning)
- {
- if (pthread_kill(thread, SIGINT))
- {
- errorStr = "Cannot kill thread.";
- printfd(__FILE__, "Cannot kill thread\n");
- return -1;
- }
- printfd(__FILE__, "REMOTE_SCRIPT killed Run\n");
+ struct timespec ts = {0, 200000000};
+ nanosleep(&ts, NULL);
}
}
users->DelNotifierUserDel(&onDelUserNotifier);
users->DelNotifierUserAdd(&onAddUserNotifier);
+if (isRunning)
+ {
+ logger("Cannot stop thread.");
+ return -1;
+ }
+
return 0;
}
//-----------------------------------------------------------------------------
if (nrMapParser.ReadFile(rsSettings.GetMapFileName()))
{
errorStr = nrMapParser.GetErrorStr();
+ logger("Map file reading error: %s", errorStr.c_str());
return -1;
}
{
- STG_LOCKER lock(&mutex, __FILE__, __LINE__);
+ STG_LOCKER lock(&mutex);
printfd(__FILE__, "REMOTE_SCRIPT::Reload()\n");
authorizedUsers.end(),
UpdateRouter(*this));
+logger("%s reloaded successfully.", rsSettings.GetMapFileName().c_str());
+printfd(__FILE__, "REMOTE_SCRIPT::Reload() %s reloaded successfully.\n");
+
return 0;
}
//-----------------------------------------------------------------------------
if (sock < 0)
{
errorStr = "Cannot create socket.";
+ logger("Canot create a socket: %s", strerror(errno));
printfd(__FILE__, "Cannot create socket\n");
return true;
}
//-----------------------------------------------------------------------------
void REMOTE_SCRIPT::PeriodicSend()
{
-STG_LOCKER lock(&mutex, __FILE__, __LINE__);
+STG_LOCKER lock(&mutex);
-map<uint32_t, RS_USER>::iterator it(authorizedUsers.begin());
+std::map<uint32_t, RS::USER>::iterator it(authorizedUsers.begin());
while (it != authorizedUsers.end())
{
if (difftime(stgTime, it->second.lastSentTime) - (rand() % halfPeriod) > sendPeriod)
- //if (stgTime - it->second.lastSentTime > sendPeriod)
{
- Send(it->first, it->second);
+ Send(it->second);
}
++it;
}
}
//-----------------------------------------------------------------------------
-bool REMOTE_SCRIPT::PreparePacket(char * buf, size_t bufSize, uint32_t ip, RS_USER & rsu, bool forceDisconnect) const
+#ifdef NDEBUG
+bool REMOTE_SCRIPT::PreparePacket(char * buf, size_t, RS::USER & rsu, bool forceDisconnect) const
+#else
+bool REMOTE_SCRIPT::PreparePacket(char * buf, size_t bufSize, RS::USER & rsu, bool forceDisconnect) const
+#endif
{
-RS_PACKET_HEADER packetHead;
+RS::PACKET_HEADER packetHead;
memset(packetHead.padding, 0, sizeof(packetHead.padding));
strcpy((char*)packetHead.magic, RS_ID);
if (forceDisconnect)
{
packetHead.packetType = RS_DISCONNECT_PACKET;
+ printfd(__FILE__, "RSCRIPT: force disconnect for '%s'\n", rsu.user->GetLogin().c_str());
}
else
{
{
//SendLong
packetHead.packetType = rsu.user->IsInetable() ? RS_CONNECT_PACKET : RS_DISCONNECT_PACKET;
+ if (rsu.user->IsInetable())
+ printfd(__FILE__, "RSCRIPT: connect for '%s'\n", rsu.user->GetLogin().c_str());
+ else
+ printfd(__FILE__, "RSCRIPT: disconnect for '%s'\n", rsu.user->GetLogin().c_str());
}
else
{
//SendShort
packetHead.packetType = rsu.user->IsInetable() ? RS_ALIVE_PACKET : RS_DISCONNECT_PACKET;
+ if (rsu.user->IsInetable())
+ printfd(__FILE__, "RSCRIPT: alive for '%s'\n", rsu.user->GetLogin().c_str());
+ else
+ printfd(__FILE__, "RSCRIPT: disconnect for '%s'\n", rsu.user->GetLogin().c_str());
}
}
rsu.shortPacketsCount++;
rsu.lastSentTime = stgTime;
-packetHead.ip = htonl(ip);
+packetHead.ip = htonl(rsu.ip);
packetHead.id = htonl(rsu.user->GetID());
strncpy((char*)packetHead.login, rsu.user->GetLogin().c_str(), RS_LOGIN_LEN);
packetHead.login[RS_LOGIN_LEN - 1] = 0;
return false;
}
-RS_PACKET_TAIL packetTail;
+RS::PACKET_TAIL packetTail;
memset(packetTail.padding, 0, sizeof(packetTail.padding));
strcpy((char*)packetTail.magic, RS_ID);
-vector<string>::const_iterator it;
+std::vector<std::string>::const_iterator it;
std::string params;
for(it = rsSettings.GetUserParams().begin();
it != rsSettings.GetUserParams().end();
++it)
{
- std::string parameter(GetUserParam(rsu.user, *it));
+ std::string parameter(rsu.user->GetParamValue(it->c_str()));
if (params.length() + parameter.length() > RS_PARAMS_LEN - 1)
+ {
+ logger("Script params string length %d exceeds the limit of %d symbols.", params.length() + parameter.length(), RS_PARAMS_LEN);
break;
+ }
params += parameter + " ";
}
strncpy((char *)packetTail.params, params.c_str(), RS_PARAMS_LEN);
return false;
}
//-----------------------------------------------------------------------------
-bool REMOTE_SCRIPT::Send(uint32_t ip, RS_USER & rsu, bool forceDisconnect) const
+bool REMOTE_SCRIPT::Send(RS::USER & rsu, bool forceDisconnect) const
{
char buffer[RS_MAX_PACKET_LEN];
memset(buffer, 0, sizeof(buffer));
-if (PreparePacket(buffer, sizeof(buffer), ip, rsu, forceDisconnect))
+if (PreparePacket(buffer, sizeof(buffer), rsu, forceDisconnect))
{
printfd(__FILE__, "REMOTE_SCRIPT::Send() - Invalid packet length!\n");
return true;
std::for_each(
rsu.routers.begin(),
rsu.routers.end(),
- PacketSender(sock, buffer, sizeof(buffer), htons(rsSettings.GetPort()))
+ PacketSender(sock, buffer, sizeof(buffer), static_cast<uint16_t>(htons(rsSettings.GetPort())))
);
return false;
}
//-----------------------------------------------------------------------------
-bool REMOTE_SCRIPT::SendDirect(uint32_t ip, RS_USER & rsu, uint32_t routerIP, bool forceDisconnect) const
+bool REMOTE_SCRIPT::SendDirect(RS::USER & rsu, uint32_t routerIP, bool forceDisconnect) const
{
char buffer[RS_MAX_PACKET_LEN];
-if (PreparePacket(buffer, sizeof(buffer), ip, rsu, forceDisconnect))
+if (PreparePacket(buffer, sizeof(buffer), rsu, forceDisconnect))
{
printfd(__FILE__, "REMOTE_SCRIPT::SendDirect() - Invalid packet length!\n");
return true;
struct sockaddr_in sendAddr;
sendAddr.sin_family = AF_INET;
-sendAddr.sin_port = htons(rsSettings.GetPort());
+sendAddr.sin_port = static_cast<uint16_t>(htons(rsSettings.GetPort()));
sendAddr.sin_addr.s_addr = routerIP;
-int res = sendto(sock, buffer, sizeof(buffer), 0, (struct sockaddr *)&sendAddr, sizeof(sendAddr));
+ssize_t res = sendto(sock, buffer, sizeof(buffer), 0, (struct sockaddr *)&sendAddr, sizeof(sendAddr));
+
+if (res < 0)
+ logger("sendto error: %s", strerror(errno));
return (res != sizeof(buffer));
}
USER_PTR u;
int h = users->OpenSearch();
-if (!h)
- {
- errorStr = "users->OpenSearch() error.";
- printfd(__FILE__, "OpenSearch() error\n");
- return true;
- }
+assert(h && "USERS::OpenSearch is always correct");
while (!users->SearchNext(h, &u))
{
- SetUserNotifier(u);
+ SetUserNotifiers(u);
}
users->CloseSearch(h);
return false;
}
//-----------------------------------------------------------------------------
-void REMOTE_SCRIPT::ChangedIP(USER_PTR u, uint32_t oldIP, uint32_t newIP)
-{
-/*
- * When ip changes process looks like:
- * old => 0, 0 => new
- *
- */
-if (newIP)
- {
- RS_USER rsu(IP2Routers(newIP), u);
- Send(newIP, rsu);
-
- STG_LOCKER lock(&mutex, __FILE__, __LINE__);
- authorizedUsers[newIP] = rsu;
- }
-else
- {
- STG_LOCKER lock(&mutex, __FILE__, __LINE__);
- const map<uint32_t, RS_USER>::iterator it(
- authorizedUsers.find(oldIP)
- );
- if (it != authorizedUsers.end())
- {
- Send(oldIP, it->second, true);
- authorizedUsers.erase(it);
- }
- }
-}
-//-----------------------------------------------------------------------------
std::vector<uint32_t> REMOTE_SCRIPT::IP2Routers(uint32_t ip)
{
-STG_LOCKER lock(&mutex, __FILE__, __LINE__);
+STG_LOCKER lock(&mutex);
for (size_t i = 0; i < netRouters.size(); ++i)
{
if ((ip & netRouters[i].subnetMask) == (netRouters[i].subnetIP & netRouters[i].subnetMask))
return std::vector<uint32_t>();
}
//-----------------------------------------------------------------------------
-string REMOTE_SCRIPT::GetUserParam(USER_PTR u, const string & paramName) const
+void REMOTE_SCRIPT::SetUserNotifiers(USER_PTR u)
{
-string value = "";
-if (strcasecmp(paramName.c_str(), "cash") == 0)
- strprintf(&value, "%f", u->GetProperty().cash.Get());
-else
-if (strcasecmp(paramName.c_str(), "freeMb") == 0)
- strprintf(&value, "%f", u->GetProperty().freeMb.Get());
-else
-if (strcasecmp(paramName.c_str(), "passive") == 0)
- strprintf(&value, "%d", u->GetProperty().passive.Get());
-else
-if (strcasecmp(paramName.c_str(), "disabled") == 0)
- strprintf(&value, "%d", u->GetProperty().disabled.Get());
-else
-if (strcasecmp(paramName.c_str(), "alwaysOnline") == 0)
- strprintf(&value, "%d", u->GetProperty().alwaysOnline.Get());
-else
-if (strcasecmp(paramName.c_str(), "tariffName") == 0 ||
- strcasecmp(paramName.c_str(), "tariff") == 0)
- value = "\"" + u->GetProperty().tariffName.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "nextTariff") == 0)
- value = "\"" + u->GetProperty().nextTariff.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "address") == 0)
- value = "\"" + u->GetProperty().address.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "note") == 0)
- value = "\"" + u->GetProperty().note.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "group") == 0)
- value = "\"" + u->GetProperty().group.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "email") == 0)
- value = "\"" + u->GetProperty().email.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "realName") == 0)
- value = "\"" + u->GetProperty().realName.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "credit") == 0)
- strprintf(&value, "%f", u->GetProperty().credit.Get());
-else
-if (strcasecmp(paramName.c_str(), "userdata0") == 0)
- value = "\"" + u->GetProperty().userdata0.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "userdata1") == 0)
- value = "\"" + u->GetProperty().userdata1.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "userdata2") == 0)
- value = "\"" + u->GetProperty().userdata2.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "userdata3") == 0)
- value = "\"" + u->GetProperty().userdata3.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "userdata4") == 0)
- value = "\"" + u->GetProperty().userdata4.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "userdata5") == 0)
- value = "\"" + u->GetProperty().userdata5.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "userdata6") == 0)
- value = "\"" + u->GetProperty().userdata6.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "userdata7") == 0)
- value = "\"" + u->GetProperty().userdata7.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "userdata8") == 0)
- value = "\"" + u->GetProperty().userdata8.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "userdata9") == 0)
- value = "\"" + u->GetProperty().userdata9.Get() + "\"";
-else
-if (strcasecmp(paramName.c_str(), "enabledDirs") == 0)
- value = u->GetEnabledDirs();
-else
- printfd(__FILE__, "Unknown value name: %s\n", paramName.c_str());
-return value;
+ipNotifierList.push_front(RS::IP_NOTIFIER(*this, u));
+connNotifierList.push_front(RS::CONNECTED_NOTIFIER(*this, u));
}
//-----------------------------------------------------------------------------
-void REMOTE_SCRIPT::SetUserNotifier(USER_PTR u)
+void REMOTE_SCRIPT::UnSetUserNotifiers(USER_PTR u)
{
-RS_CHG_AFTER_NOTIFIER<uint32_t> afterChgIPNotifier(*this, u);
+ipNotifierList.erase(std::remove_if(ipNotifierList.begin(),
+ ipNotifierList.end(),
+ USER_IS<IP_NOTIFIER>(u)),
+ ipNotifierList.end());
+connNotifierList.erase(std::remove_if(connNotifierList.begin(),
+ connNotifierList.end(),
+ USER_IS<CONNECTED_NOTIFIER>(u)),
+ connNotifierList.end());
-afterChgIPNotifierList.push_front(afterChgIPNotifier);
-
-u->AddCurrIPAfterNotifier(&(*afterChgIPNotifierList.begin()));
}
//-----------------------------------------------------------------------------
-void REMOTE_SCRIPT::UnSetUserNotifier(USER_PTR u)
+void REMOTE_SCRIPT::AddRSU(USER_PTR user)
{
-list<RS_CHG_AFTER_NOTIFIER<uint32_t> >::iterator ipAIter;
-std::list<list<RS_CHG_AFTER_NOTIFIER<uint32_t> >::iterator> toErase;
+RS::USER rsu(IP2Routers(user->GetCurrIP()), user);
+Send(rsu);
-for (ipAIter = afterChgIPNotifierList.begin(); ipAIter != afterChgIPNotifierList.end(); ++ipAIter)
+STG_LOCKER lock(&mutex);
+authorizedUsers.insert(std::make_pair(user->GetCurrIP(), rsu));
+}
+//-----------------------------------------------------------------------------
+void REMOTE_SCRIPT::DelRSU(USER_PTR user)
+{
+STG_LOCKER lock(&mutex);
+std::map<uint32_t, RS::USER>::iterator it(authorizedUsers.begin());
+while (it != authorizedUsers.end())
{
- if (ipAIter->GetUser() == u)
+ if (it->second.user == user)
{
- u->DelCurrIPAfterNotifier(&(*ipAIter));
- toErase.push_back(ipAIter);
+ Send(it->second, true);
+ authorizedUsers.erase(it);
+ return;
}
+ ++it;
}
-
-std::list<list<RS_CHG_AFTER_NOTIFIER<uint32_t> >::iterator>::iterator eIter;
-
-for (eIter = toErase.begin(); eIter != toErase.end(); ++eIter)
+/*const std::map<uint32_t, RS::USER>::iterator it(
+ authorizedUsers.find(user->GetCurrIP())
+ );
+if (it != authorizedUsers.end())
{
- afterChgIPNotifierList.erase(*eIter);
- }
+ Send(it->second, true);
+ authorizedUsers.erase(it);
+ }*/
+}
+//-----------------------------------------------------------------------------
+void RS::IP_NOTIFIER::Notify(const uint32_t & /*oldValue*/, const uint32_t & newValue)
+{
+if (newValue)
+ rs.AddRSU(user);
+else
+ rs.DelRSU(user);
}
//-----------------------------------------------------------------------------
-template <typename varParamType>
-void RS_CHG_AFTER_NOTIFIER<varParamType>::Notify(const varParamType & oldValue, const varParamType & newValue)
+void RS::CONNECTED_NOTIFIER::Notify(const bool & /*oldValue*/, const bool & newValue)
{
-rs.ChangedIP(user, oldValue, newValue);
+if (newValue)
+ rs.AddRSU(user);
+else
+ rs.DelRSU(user);
}
//-----------------------------------------------------------------------------
-void REMOTE_SCRIPT::InitEncrypt(BLOWFISH_CTX * ctx, const string & password) const
+void REMOTE_SCRIPT::InitEncrypt(BLOWFISH_CTX * ctx, const std::string & password) const
{
unsigned char keyL[PASSWD_LEN]; // Пароль для шифровки
memset(keyL, 0, PASSWD_LEN);
Blowfish_Init(ctx, keyL, PASSWD_LEN);
}
//-----------------------------------------------------------------------------
-void REMOTE_SCRIPT::Encrypt(BLOWFISH_CTX * ctx, char * dst, const char * src, size_t len8) const
+void REMOTE_SCRIPT::Encrypt(BLOWFISH_CTX * ctx, void * dst, const void * src, size_t len8) const
{
if (dst != src)
memcpy(dst, src, len8 * 8);
for (size_t i = 0; i < len8; ++i)
- Blowfish_Encrypt(ctx, (uint32_t *)(dst + i * 8), (uint32_t *)(dst + i * 8 + 4));
+ Blowfish_Encrypt(ctx, static_cast<uint32_t *>(dst) + i * 2, static_cast<uint32_t *>(dst) + i * 2 + 1);
}
//-----------------------------------------------------------------------------
git.stg.codes / stg.git / blobdiff