rdr

1 files changed, 247 insertions, 0 deletions

diff --git a/rdr/FdInStream.cxx b/rdr/FdInStream.cxx
new file mode 100644
index 0000000..b5c4984
--- /dev/null
+++ b/rdr/FdInStream.cxx
@@ -0,0 +1,247 @@
+//
+// Copyright (C) 2002 RealVNC Ltd.  All Rights Reserved.
+//
+// This 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 2 of the License, or
+// (at your option) any later version.
+//
+// This software 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 software; if not, write to the Free Software
+// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307,
+// USA.
+
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <sys/types.h>
+#ifdef _WIN32
+#include <winsock.h>
+#include <sys/timeb.h>
+#define read(s,b,l) recv(s,(char*)b,l,0)
+#undef errno
+#define errno WSAGetLastError()
+#else
+#include <unistd.h>
+#include <sys/time.h>
+#endif
+
+// XXX should use autoconf HAVE_SYS_SELECT_H
+#ifdef _AIX
+#include <sys/select.h>
+#endif
+
+#include <rdr/FdInStream.h>
+#include <rdr/Exception.h>
+
+using namespace rdr;
+
+enum { DEFAULT_BUF_SIZE = 8192,
+       MIN_BULK_SIZE = 1024 };
+
+FdInStream::FdInStream(int fd_, int timeout_, int bufSize_)
+  : fd(fd_), timeout(timeout_), blockCallback(0), blockCallbackArg(0),
+    timing(false), timeWaitedIn100us(5), timedKbits(0),
+    bufSize(bufSize_ ? bufSize_ : DEFAULT_BUF_SIZE), offset(0)
+{
+  ptr = end = start = new U8[bufSize];
+}
+
+FdInStream::FdInStream(int fd_, void (*blockCallback_)(void*),
+                       void* blockCallbackArg_, int bufSize_)
+  : fd(fd_), timeout(0), blockCallback(blockCallback_),
+    blockCallbackArg(blockCallbackArg_),
+    timing(false), timeWaitedIn100us(5), timedKbits(0),
+    bufSize(bufSize_ ? bufSize_ : DEFAULT_BUF_SIZE), offset(0)
+{
+  ptr = end = start = new U8[bufSize];
+}
+
+FdInStream::~FdInStream()
+{
+  delete [] start;
+}
+
+
+int FdInStream::pos()
+{
+  return offset + ptr - start;
+}
+
+void FdInStream::readBytes(void* data, int length)
+{
+  if (length < MIN_BULK_SIZE) {
+    InStream::readBytes(data, length);
+    return;
+  }
+
+  U8* dataPtr = (U8*)data;
+
+  int n = end - ptr;
+  if (n > length) n = length;
+
+  memcpy(dataPtr, ptr, n);
+  dataPtr += n;
+  length -= n;
+  ptr += n;
+
+  while (length > 0) {
+    n = readWithTimeoutOrCallback(dataPtr, length);
+    dataPtr += n;
+    length -= n;
+    offset += n;
+  }
+}
+
+
+int FdInStream::overrun(int itemSize, int nItems)
+{
+  if (itemSize > bufSize)
+    throw Exception("FdInStream overrun: max itemSize exceeded");
+
+  if (end - ptr != 0)
+    memmove(start, ptr, end - ptr);
+
+  offset += ptr - start;
+  end -= ptr - start;
+  ptr = start;
+
+  while (end < start + itemSize) {
+    int n = readWithTimeoutOrCallback((U8*)end, start + bufSize - end);
+    end += n;
+  }
+
+  if (itemSize * nItems > end - ptr)
+    nItems = (end - ptr) / itemSize;
+
+  return nItems;
+}
+
+int FdInStream::checkReadable(int fd, int timeout)
+{
+  while (true) {
+    fd_set rfds;
+    struct timeval tv;
+    
+    tv.tv_sec = timeout / 1000;
+    tv.tv_usec = (timeout % 1000) * 1000;
+
+    FD_ZERO(&rfds);
+    FD_SET(fd, &rfds);
+    int n = select(fd+1, &rfds, 0, 0, &tv);
+    if (n != -1 || errno != EINTR)
+      return n;
+    fprintf(stderr,"select returned EINTR\n");
+  }
+}
+
+#ifdef _WIN32
+static void gettimeofday(struct timeval* tv, void*)
+{
+  LARGE_INTEGER counts, countsPerSec;
+  static double usecPerCount = 0.0;
+
+  if (QueryPerformanceCounter(&counts)) {
+    if (usecPerCount == 0.0) {
+      QueryPerformanceFrequency(&countsPerSec);
+      usecPerCount = 1000000.0 / countsPerSec.QuadPart;
+    }
+
+    LONGLONG usecs = (LONGLONG)(counts.QuadPart * usecPerCount);
+    tv->tv_usec = (long)(usecs % 1000000);
+    tv->tv_sec = (long)(usecs / 1000000);
+
+  } else {
+    struct timeb tb;
+    ftime(&tb);
+    tv->tv_sec = tb.time;
+    tv->tv_usec = tb.millitm * 1000;
+  }
+}
+#endif
+
+int FdInStream::readWithTimeoutOrCallback(void* buf, int len)
+{
+  struct timeval before, after;
+  if (timing)
+    gettimeofday(&before, 0);
+
+  int n = checkReadable(fd, timeout);
+
+  if (n < 0) throw SystemException("select",errno);
+
+  if (n == 0) {
+    if (timeout) throw TimedOut();
+    if (blockCallback) (*blockCallback)(blockCallbackArg);
+  }
+
+  while (true) {
+    n = ::read(fd, buf, len);
+    if (n != -1 || errno != EINTR)
+      break;
+    fprintf(stderr,"read returned EINTR\n");
+  }
+
+  if (n < 0) throw SystemException("read",errno);
+  if (n == 0) throw EndOfStream();
+
+  if (timing) {
+    gettimeofday(&after, 0);
+//      fprintf(stderr,"%d.%06d\n",(after.tv_sec - before.tv_sec),
+//              (after.tv_usec - before.tv_usec));
+    int newTimeWaited = ((after.tv_sec - before.tv_sec) * 10000 +
+                         (after.tv_usec - before.tv_usec) / 100);
+    int newKbits = n * 8 / 1000;
+
+//      if (newTimeWaited == 0) {
+//        fprintf(stderr,"new kbps infinite t %d k %d\n",
+//                newTimeWaited, newKbits);
+//      } else {
+//        fprintf(stderr,"new kbps %d t %d k %d\n",
+//                newKbits * 10000 / newTimeWaited, newTimeWaited, newKbits);
+//      }
+
+    // limit rate to between 10kbit/s and 40Mbit/s
+
+    if (newTimeWaited > newKbits*1000) newTimeWaited = newKbits*1000;
+    if (newTimeWaited < newKbits/4)    newTimeWaited = newKbits/4;
+
+    timeWaitedIn100us += newTimeWaited;
+    timedKbits += newKbits;
+  }
+
+  return n;
+}
+
+void FdInStream::startTiming()
+{
+  timing = true;
+
+  // Carry over up to 1s worth of previous rate for smoothing.
+
+  if (timeWaitedIn100us > 10000) {
+    timedKbits = timedKbits * 10000 / timeWaitedIn100us;
+    timeWaitedIn100us = 10000;
+  }
+}
+
+void FdInStream::stopTiming()
+{
+  timing = false; 
+  if (timeWaitedIn100us < timedKbits/2)
+    timeWaitedIn100us = timedKbits/2; // upper limit 20Mbit/s
+}
+
+unsigned int FdInStream::kbitsPerSecond()
+{
+  // The following calculation will overflow 32-bit arithmetic if we have
+  // received more than about 50Mbytes (400Mbits) since we started timing, so
+  // it should be OK for a single RFB update.
+
+  return timedKbits * 10000 / timeWaitedIn100us;
+}