eDVBResourceManager *eDVBResourceManager::instance;
+RESULT eDVBResourceManager::getInstance(ePtr<eDVBResourceManager> &ptr)
+{
+ if (instance)
+ {
+ ptr = instance;
+ return 0;
+ }
+ return -1;
+}
+
+ePtr<eDVBResourceManager> NewResourceManagerPtr(void)
+{
+ ePtr<eDVBResourceManager> ptr;
+ eDVBResourceManager::getInstance(ptr);
+ return ptr;
+}
+
eDVBResourceManager::eDVBResourceManager()
:m_releaseCachedChannelTimer(eApp)
{
CONNECT(m_releaseCachedChannelTimer.timeout, eDVBResourceManager::releaseCachedChannel);
}
+void eDVBResourceManager::feStateChanged()
+{
+ int mask=0;
+ for (eSmartPtrList<eDVBRegisteredFrontend>::iterator i(m_frontend.begin()); i != m_frontend.end(); ++i)
+ if (i->m_inuse)
+ mask |= ( 1 << i->m_frontend->getID() );
+ /* emit */ frontendUseMaskChanged(mask);
+}
DEFINE_REF(eDVBAdapterLinux);
eDVBAdapterLinux::eDVBAdapterLinux(int nr): m_nr(nr)
m_demux.push_back(new eDVBRegisteredDemux(demux, adapter));
}
+ ePtr<eDVBRegisteredFrontend> prev_dvbt_frontend;
for (i=0; i<num_fe; ++i)
{
ePtr<eDVBFrontend> frontend;
-
if (!adapter->getFrontend(frontend, i))
{
+ int frontendType=0;
+ frontend->getFrontendType(frontendType);
+ eDVBRegisteredFrontend *new_fe = new eDVBRegisteredFrontend(frontend, adapter);
+ CONNECT(new_fe->stateChanged, eDVBResourceManager::feStateChanged);
+ m_frontend.push_back(new_fe);
frontend->setSEC(m_sec);
- m_frontend.push_back(new eDVBRegisteredFrontend(frontend, adapter));
+ // we must link all dvb-t frontends ( for active antenna voltage )
+ if (frontendType == iDVBFrontend::feTerrestrial)
+ {
+ if (prev_dvbt_frontend)
+ {
+ prev_dvbt_frontend->m_frontend->setData(eDVBFrontend::LINKED_NEXT_PTR, (int)new_fe);
+ frontend->setData(eDVBFrontend::LINKED_PREV_PTR, (int)&(*prev_dvbt_frontend));
+ }
+ prev_dvbt_frontend = new_fe;
+ }
}
}
}
int n=0;
/* FIXME: hardware demux policy */
if (!(cap & iDVBChannel::capDecode))
- ++i, ++n;
+ {
+ if (m_demux.size() > 2) /* assumed to be true, otherwise we have lost anyway */
+ {
+ ++i, ++n;
+ ++i, ++n;
+ }
+ }
for (; i != m_demux.end(); ++i, ++n)
- if ((!i->m_inuse) && ((!fe) || (i->m_adapter == fe->m_adapter)))
+ {
+ int is_decode = n < 2;
+
+ int in_use = is_decode ? (i->m_demux->getRefCount() != 2) : i->m_inuse;
+
+ if ((!in_use) && ((!fe) || (i->m_adapter == fe->m_adapter)))
{
- if ((cap & iDVBChannel::capDecode) && n)
+ if ((cap & iDVBChannel::capDecode) && !is_decode)
continue;
demux = new eDVBAllocatedDemux(i);
demux->get().setSourcePVR(0);
return 0;
}
+ }
eDebug("demux not found");
return -1;
}
channel = m_cached_channel;
return 0;
}
+ m_cached_channel_state_changed_conn.disconnect();
m_cached_channel=0;
+ m_releaseCachedChannelTimer.stop();
}
// eDebug("allocate channel.. %04x:%04x", channelid.transport_stream_id.get(), channelid.original_network_id.get());
return errChidNotFound;
}
m_cached_channel = channel = ch;
- CONNECT(ch->m_stateChanged,eDVBResourceManager::DVBChannelStateChanged);
+ m_cached_channel_state_changed_conn =
+ CONNECT(ch->m_stateChanged,eDVBResourceManager::DVBChannelStateChanged);
return 0;
}
void eDVBResourceManager::releaseCachedChannel()
{
- eDebug("release cached channel");
+ eDebug("release cached channel (timer timeout)");
m_cached_channel=0;
}
ePtr<eDVBAllocatedFrontend> fe;
if (m_cached_channel)
+ {
+ m_cached_channel_state_changed_conn.disconnect();
m_cached_channel=0;
+ m_releaseCachedChannelTimer.stop();
+ }
if (allocateFrontendByIndex(fe, frontend_index))
return errNoFrontend;
{
ePtr<eDVBAllocatedDemux> demux;
- if (m_cached_channel)
+ if (m_cached_channel && m_releaseCachedChannelTimer.isActive())
+ {
+ m_cached_channel_state_changed_conn.disconnect();
m_cached_channel=0;
+ m_releaseCachedChannelTimer.stop();
+ }
eDVBChannel *ch;
ch = new eDVBChannel(this, 0);
-
+
channel = ch;
return 0;
}
return 0;
}
-bool eDVBResourceManager::canAllocateFrontend(ePtr<iDVBFrontendParameters> &feparm)
+int eDVBResourceManager::canAllocateFrontend(ePtr<iDVBFrontendParameters> &feparm)
{
ePtr<eDVBRegisteredFrontend> best;
int bestval = 0;
bestval = c;
}
- return bestval>0;
+ return bestval;
}
-bool eDVBResourceManager::canAllocateChannel(const eDVBChannelID &channelid, const eDVBChannelID& ignore)
+int eDVBResourceManager::canAllocateChannel(const eDVBChannelID &channelid, const eDVBChannelID& ignore)
{
- bool ret=true;
+ int ret=30000;
if (m_cached_channel)
{
eDVBChannel *cache_chan = (eDVBChannel*)&(*m_cached_channel);
if (i->m_channel_id == ignore)
{
eDVBChannel *channel = (eDVBChannel*) &(*i->m_channel);
- if (channel == &(*m_cached_channel) ? channel->getUseCount() == 2 : channel->getUseCount() == 1) // channel only used once..
+ // one eUsePtr<iDVBChannel> is used in eDVBServicePMTHandler
+ // another on eUsePtr<iDVBChannel> is used in the eDVBScan instance used in eDVBServicePMTHandler (for SDT scan)
+ // so we must check here if usecount is 3 (when the channel is equal to the cached channel)
+ // or 2 when the cached channel is not equal to the compared channel
+ if (channel == &(*m_cached_channel) ? channel->getUseCount() == 3 : channel->getUseCount() == 2) // channel only used once..
{
ePtr<iDVBFrontend> fe;
if (!i->m_channel->getFrontend(fe))
if (!m_list)
{
eDebug("no channel list set!");
- ret = false;
+ ret = 0;
goto error;
}
if (m_list->getChannelFrontendData(channelid, feparm))
{
eDebug("channel not found!");
- ret = false;
+ ret = 0;
goto error;
}
return ret;
}
+class eDVBChannelFilePush: public eFilePushThread
+{
+public:
+ void setIFrameSearch(int enabled) { m_iframe_search = enabled; m_iframe_state = 0; }
+protected:
+ int m_iframe_search, m_iframe_state, m_pid;
+ int filterRecordData(const unsigned char *data, int len, size_t ¤t_span_remaining);
+};
+
+int eDVBChannelFilePush::filterRecordData(const unsigned char *_data, int len, size_t ¤t_span_remaining)
+{
+#if 0 /* not yet */
+ if (!m_iframe_search)
+ return len;
+
+ unsigned char *data = (unsigned char*)_data; /* remove that const. we know what we are doing. */
+
+ eDebug("filterRecordData, size=%d (mod 188=%d), first byte is %02x", len, len %188, data[0]);
+
+ unsigned char *d = data;
+ while ((d = (unsigned char*)memmem(d, data + len - d, "\x00\x00\x01", 3)))
+ {
+ int offset = d - data;
+ int ts_offset = offset - offset % 188; /* offset to the start of TS packet */
+ unsigned char *ts = data + ts_offset;
+ int pid = ((ts[1] << 8) | ts[2]) & 0x1FFF;
+
+ if ((d[3] == 0) && (m_pid == pid)) /* picture start */
+ {
+ int picture_type = (d[5] >> 3) & 7;
+ d += 4;
+
+ eDebug("%d-frame at %d, offset in TS packet: %d, pid=%04x", picture_type, offset, offset % 188, pid);
+
+ if (m_iframe_state == 1)
+ {
+ /* we are allowing data, and stop allowing data on the next frame.
+ we now found a frame. so stop here. */
+ memset(data + offset, 0, 188 - (offset%188)); /* zero out rest of TS packet */
+ current_span_remaining = 0;
+ m_iframe_state = 0;
+ unsigned char *fts = ts + 188;
+ while (fts < (data + len))
+ {
+ fts[1] |= 0x1f;
+ fts[2] |= 0xff; /* drop packet */
+ fts += 188;
+ }
+
+ return len; // ts_offset + 188; /* deliver this packet, but not more. */
+ } else
+ {
+ if (picture_type != 1) /* we are only interested in I frames */
+ continue;
+
+ unsigned char *fts = data;
+ while (fts < ts)
+ {
+ fts[1] |= 0x1f;
+ fts[2] |= 0xff; /* drop packet */
+
+ fts += 188;
+ }
+ /* force payload only */
+ ts[3] &= ~0x30;
+ ts[3] |= 0x10;
+
+// memset(ts + 4, 0xFF, (offset % 188) - 4);
+
+ m_iframe_state = 1;
+ }
+ } else if ((d[3] & 0xF0) == 0xE0) /* video stream */
+ {
+ if (m_pid != pid)
+ {
+ eDebug("now locked to pid %04x", pid);
+ m_pid = pid;
+ }
+// m_pid = 0x6e;
+ d += 4;
+ } else
+ d += 4; /* ignore */
+
+ }
+
+ if (m_iframe_state == 1)
+ return len;
+ else
+ return 0; /* we need find an iframe first */
+#else
+ return len;
+#endif
+}
+
DEFINE_REF(eDVBChannel);
eDVBChannel::eDVBChannel(eDVBResourceManager *mgr, eDVBAllocatedFrontend *frontend): m_state(state_idle), m_mgr(mgr)
} else if (state == iDVBFrontend::stateLostLock)
{
/* on managed channels, we try to retune in order to re-acquire lock. */
- if (m_feparm)
+ if (m_current_frontend_parameters)
{
eDebug("OURSTATE: lost lock, trying to retune");
ourstate = state_tuning;
- m_frontend->get().tune(*m_feparm);
+ m_frontend->get().tune(*m_current_frontend_parameters);
} else
/* on unmanaged channels, we don't do this. the client will do this. */
{
eDebug("skipmode ratio is %lld:90000, bitrate is %d bit/s", m_cue->m_skipmode_ratio, bitrate);
/* i agree that this might look a bit like black magic. */
m_skipmode_n = 512*1024; /* must be 1 iframe at least. */
- m_skipmode_m = bitrate / 8 / 90000 * m_cue->m_skipmode_ratio;
+ m_skipmode_m = bitrate / 8 / 90000 * m_cue->m_skipmode_ratio / 8;
+
+ if (m_cue->m_skipmode_ratio < 0)
+ m_skipmode_m -= m_skipmode_n;
eDebug("resolved to: %d %d", m_skipmode_m, m_skipmode_n);
if (abs(m_skipmode_m) < abs(m_skipmode_n))
{
- eFatal("damn, something is wrong with this calculation");
+ eWarning("something is wrong with this calculation");
m_skipmode_n = m_skipmode_m = 0;
}
m_skipmode_n = m_skipmode_m = 0;
}
}
+ m_pvr_thread->setIFrameSearch(m_skipmode_n != 0);
+ eDebug("flush pvr");
flushPVR(m_cue->m_decoding_demux);
+ eDebug("done");
break;
}
case eCueSheet::evtSpanChanged:
- eDebug("source span translation not yet supported");
- // recheckCuesheetSpans();
+ {
+ m_source_span.clear();
+ for (std::list<std::pair<pts_t, pts_t> >::const_iterator i(m_cue->m_spans.begin()); i != m_cue->m_spans.end(); ++i)
+ {
+ off_t offset_in, offset_out;
+ pts_t pts_in = i->first, pts_out = i->second;
+ if (m_tstools.getOffset(offset_in, pts_in) || m_tstools.getOffset(offset_out, pts_out))
+ {
+ eDebug("span translation failed.\n");
+ continue;
+ }
+ eDebug("source span: %llx .. %llx, translated to %llx..%llx", pts_in, pts_out, offset_in, offset_out);
+ m_source_span.push_back(std::pair<off_t, off_t>(offset_in, offset_out));
+ }
break;
}
+ }
+}
+
+ /* align toward zero */
+static inline long long align(long long x, int align)
+{
+ int sign = x < 0;
+
+ if (sign)
+ x = -x;
+
+ x -= x % align;
+
+ if (sign)
+ x = -x;
+
+ return x;
}
/* remember, this gets called from another thread. */
void eDVBChannel::getNextSourceSpan(off_t current_offset, size_t bytes_read, off_t &start, size_t &size)
{
- unsigned int max = 10*1024*1024;
+ const int blocksize = 188;
+ unsigned int max = align(10*1024*1024, blocksize);
+ current_offset = align(current_offset, blocksize);
if (!m_cue)
{
eDebug("getNextSourceSpan, no decoding demux. forcing normal play");
return;
}
-
+
if (m_skipmode_n)
{
eDebug("skipmode %d:%d", m_skipmode_m, m_skipmode_n);
- max = m_skipmode_n;
+ max = align(m_skipmode_n, blocksize);
}
-
+
eDebug("getNextSourceSpan, current offset is %08llx!", current_offset);
-
- if ((current_offset < -m_skipmode_m) && (m_skipmode_m < 0))
- {
- eDebug("reached SOF");
- m_skipmode_m = 0;
- m_pvr_thread->sendEvent(eFilePushThread::evtUser);
- }
-
- current_offset += m_skipmode_m;
-
+
+ current_offset += align(m_skipmode_m, blocksize);
+
while (!m_cue->m_seek_requests.empty())
{
std::pair<int, pts_t> seek = m_cue->m_seek_requests.front();
int relative = seek.first;
pts_t pts = seek.second;
- int bitrate = m_tstools.calcBitrate(); /* in bits/s */
-
- if (bitrate == -1)
- continue;
-
+ pts_t now = 0;
if (relative)
{
- pts_t now;
- /* we're using the decoder's timestamp here. this
- won't work for radio (ouch). */
+ if (!m_cue->m_decoder)
+ {
+ eDebug("no decoder - can't seek relative");
+ continue;
+ }
+ if (m_cue->m_decoder->getPTS(0, now))
+ {
+ eDebug("decoder getPTS failed, can't seek relative");
+ continue;
+ }
if (getCurrentPosition(m_cue->m_decoding_demux, now, 1))
{
eDebug("seekTo: getCurrentPosition failed!");
continue;
}
+ } else if (pts < 0) /* seek relative to end */
+ {
+ pts_t len;
+ if (!getLength(len))
+ {
+ eDebug("seeking relative to end. len=%lld, seek = %lld", len, pts);
+ pts += len;
+ } else
+ {
+ eWarning("getLength failed - can't seek relative to end!");
+ continue;
+ }
+ }
+
+ if (relative == 1) /* pts relative */
+ {
pts += now;
+ if (pts < 0)
+ pts = 0;
+ }
+
+ if (relative != 2)
+ if (pts < 0)
+ pts = 0;
+
+ if (relative == 2) /* AP relative */
+ {
+ eDebug("AP relative seeking: %lld, at %lld", pts, now);
+ pts_t nextap;
+ if (m_tstools.getNextAccessPoint(nextap, now, pts))
+ {
+ pts = now;
+ eDebug("AP relative seeking failed!");
+ } else
+ {
+ eDebug("next ap is %llx\n", pts);
+ pts = nextap;
+ }
}
-
- if (pts < 0)
- pts = 0;
-
- off_t offset = (pts * (pts_t)bitrate) / 8ULL / 90000ULL;
+ off_t offset = 0;
+ if (m_tstools.getOffset(offset, pts))
+ {
+ eDebug("get offset for pts=%lld failed!", pts);
+ continue;
+ }
+
eDebug("ok, resolved skip (rel: %d, diff %lld), now at %08llx", relative, pts, offset);
current_offset = offset;
}
-
+
for (std::list<std::pair<off_t, off_t> >::const_iterator i(m_source_span.begin()); i != m_source_span.end(); ++i)
{
- if ((current_offset >= i->first) && (current_offset < i->second))
+ int aligned_start = align(i->first, blocksize);
+ int aligned_end = align(i->second, blocksize);
+
+ if ((current_offset >= aligned_start) && (current_offset < aligned_end))
{
start = current_offset;
- size = i->second - current_offset;
- if (size > max)
+ /* max can not exceed max(size_t). aligned_end - current_offset, however, can. */
+ if ((aligned_end - current_offset) > max)
size = max;
- eDebug("HIT, %lld < %lld < %lld", i->first, current_offset, i->second);
+ else
+ size = aligned_end - current_offset;
+ eDebug("HIT, %lld < %lld < %lld, size: %d", i->first, current_offset, i->second, size);
return;
}
- if (current_offset < i->first)
+ if (current_offset < aligned_start)
{
- start = i->first;
- size = i->second - i->first;
- if (size > max)
- size = max;
- eDebug("skip");
+ /* ok, our current offset is in an 'out' zone. */
+ if ((m_skipmode_m >= 0) || (i == m_source_span.begin()))
+ {
+ /* in normal playback, just start at the next zone. */
+ start = i->first;
+
+ /* size is not 64bit! */
+ if ((i->second - i->first) > max)
+ size = max;
+ else
+ size = aligned_end - aligned_start;
+
+ eDebug("skip");
+ if (m_skipmode_m < 0)
+ {
+ eDebug("reached SOF");
+ /* reached SOF */
+ m_skipmode_m = 0;
+ m_pvr_thread->sendEvent(eFilePushThread::evtUser);
+ }
+ } else
+ {
+ /* when skipping reverse, however, choose the zone before. */
+ --i;
+ eDebug("skip to previous block, which is %llx..%llx", i->first, i->second);
+ size_t len;
+
+ if ((i->second - i->first) > max)
+ len = max;
+ else
+ len = aligned_end - aligned_start;
+
+ start = aligned_end - len;
+ eDebug("skipping to %llx, %d", start, len);
+ }
return;
}
}
+ if ((current_offset < -m_skipmode_m) && (m_skipmode_m < 0))
+ {
+ eDebug("reached SOF");
+ m_skipmode_m = 0;
+ m_pvr_thread->sendEvent(eFilePushThread::evtUser);
+ }
+
start = current_offset;
size = max;
+
eDebug("END OF CUESHEET. (%08llx, %d)", start, size);
-
- if (size < 4096)
- eFatal("blub");
return;
}
/* if tuning fails, shutdown the channel immediately. */
int res;
res = m_frontend->get().tune(*feparm);
- m_feparm = feparm;
+ m_current_frontend_parameters = feparm;
if (res)
{
demux = *our_demux;
/* don't hold a reference to the decoding demux, we don't need it. */
+
+ /* FIXME: by dropping the 'allocated demux' in favour of the 'iDVBDemux',
+ the refcount is lost. thus, decoding demuxes are never allocated.
+
+ this poses a big problem for PiP. */
if (cap & capDecode)
our_demux = 0;
return 0;
RESULT eDVBChannel::getFrontend(ePtr<iDVBFrontend> &frontend)
{
+ frontend = 0;
+ if (!m_frontend)
+ return -ENODEV;
frontend = &m_frontend->get();
if (frontend)
return 0;
- else
- return -ENODEV;
+ return -ENODEV;
+}
+
+RESULT eDVBChannel::getCurrentFrontendParameters(ePtr<iDVBFrontendParameters> ¶m)
+{
+ param = m_current_frontend_parameters;
+ return 0;
}
RESULT eDVBChannel::playFile(const char *file)
THEN DO A REAL FIX HERE! */
/* (this codepath needs to be improved anyway.) */
+#if HAVE_DVB_API_VERSION < 3
+ m_pvr_fd_dst = open("/dev/pvr", O_WRONLY);
+#else
m_pvr_fd_dst = open("/dev/misc/pvr", O_WRONLY);
+#endif
if (m_pvr_fd_dst < 0)
{
eDebug("can't open /dev/misc/pvr - you need to buy the new(!) $$$ box! (%m)"); // or wait for the driver to be improved.
return -ENODEV;
}
-
- m_pvr_fd_src = open(file, O_RDONLY|O_LARGEFILE);
- if (m_pvr_fd_src < 0)
+
+ m_pvr_thread = new eDVBChannelFilePush();
+ m_pvr_thread->enablePVRCommit(1);
+ m_pvr_thread->setStreamMode(1);
+ m_pvr_thread->setScatterGather(this);
+
+ if (m_pvr_thread->start(file, m_pvr_fd_dst))
{
- eDebug("can't open PVR m_pvr_fd_src file %s (%m)", file);
- close(m_pvr_fd_dst);
+ delete m_pvr_thread;
+ m_pvr_thread = 0;
+ eDebug("can't open PVR file %s (%m)", file);
return -ENOENT;
}
-
+ CONNECT(m_pvr_thread->m_event, eDVBChannel::pvrEvent);
+
m_state = state_ok;
m_stateChanged(this);
-
- m_pvr_thread = new eFilePushThread();
- m_pvr_thread->enablePVRCommit(1);
- m_pvr_thread->setScatterGather(this);
-
- m_pvr_thread->start(m_pvr_fd_src, m_pvr_fd_dst);
- CONNECT(m_pvr_thread->m_event, eDVBChannel::pvrEvent);
return 0;
}
if (m_pvr_thread)
{
m_pvr_thread->stop();
- ::close(m_pvr_fd_src);
::close(m_pvr_fd_dst);
delete m_pvr_thread;
m_pvr_thread = 0;
if (!decoding_demux)
return -1;
- off_t begin = 0;
- /* getPTS for offset 0 is cached, so it doesn't harm. */
- int r = m_tstools.getPTS(begin, pos);
- if (r)
- {
- eDebug("tstools getpts(0) failed!");
- return r;
- }
-
pts_t now;
- /* TODO: this is a gross hack. */
- r = decoding_demux->getSTC(now, mode ? 128 : 0);
-
- if (r)
+ int r;
+
+ if (mode == 0) /* demux */
{
- eDebug("demux getSTC failed");
- return -1;
- }
+ r = decoding_demux->getSTC(now, 0);
+ if (r)
+ {
+ eDebug("demux getSTC failed");
+ return -1;
+ }
+ } else
+ now = pos; /* fixup supplied */
-// eDebug("STC: %08llx PTS: %08llx, diff %lld", now, pos, now - pos);
- /* when we are less than 10 seconds before the start, return 0. */
- /* (we're just waiting for the timespam to start) */
- if ((now < pos) && ((pos - now) < 90000 * 10))
+ off_t off = 0; /* TODO: fixme */
+ r = m_tstools.fixupPTS(off, now);
+ if (r)
{
- pos = 0;
- return 0;
+ eDebug("fixup PTS failed");
+ return -1;
}
- if (now < pos) /* wrap around */
- pos = now + ((pts_t)1)<<33 - pos;
- else
- pos = now - pos;
+ pos = now;
return 0;
}
void eCueSheet::seekTo(int relative, const pts_t &pts)
{
{
- eSingleLock l(m_lock);
+ eSingleLocker l(m_lock);
m_seek_requests.push_back(std::pair<int, pts_t>(relative, pts));
}
m_event(evtSeek);
void eCueSheet::clear()
{
- eSingleLock l(m_lock);
+ eSingleLocker l(m_lock);
m_spans.clear();
}
void eCueSheet::addSourceSpan(const pts_t &begin, const pts_t &end)
{
{
- eSingleLock l(m_lock);
+ eSingleLocker l(m_lock);
m_spans.push_back(std::pair<pts_t, pts_t>(begin, end));
}
+}
+
+void eCueSheet::commitSpans()
+{
m_event(evtSpanChanged);
}
void eCueSheet::setSkipmode(const pts_t &ratio)
{
{
- eSingleLock l(m_lock);
+ eSingleLocker l(m_lock);
m_skipmode_ratio = ratio;
}
m_event(evtSkipmode);
}
-void eCueSheet::setDecodingDemux(iDVBDemux *demux)
+void eCueSheet::setDecodingDemux(iDVBDemux *demux, iTSMPEGDecoder *decoder)
{
m_decoding_demux = demux;
+ m_decoder = decoder;
}
RESULT eCueSheet::connectEvent(const Slot1<void,int> &event, ePtr<eConnection> &connection)
git.cweiske.de / enigma2.git / blobdiff