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- /* Copyright (C) 2002-2005 RealVNC Ltd. All Rights Reserved.
- * Copyright 2011 Pierre Ossman for Cendio AB
- * Copyright 2017 Peter Astrand <astrand@cendio.se> for Cendio AB
- *
- * 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.
- */
-
- #ifdef HAVE_CONFIG_H
- #include <config.h>
- #endif
-
- #include <stdio.h>
- #include <string.h>
- #include <errno.h>
- #ifdef _WIN32
- #include <winsock2.h>
- #undef errno
- #define errno WSAGetLastError()
- #include <os/winerrno.h>
- #else
- #include <sys/types.h>
- #include <unistd.h>
- #include <sys/time.h>
- #include <sys/socket.h>
- #endif
-
- /* Old systems have select() in sys/time.h */
- #ifdef HAVE_SYS_SELECT_H
- #include <sys/select.h>
- #endif
-
- #include <rdr/FdOutStream.h>
- #include <rdr/Exception.h>
- #include <rfb/util.h>
-
-
- using namespace rdr;
-
- enum { DEFAULT_BUF_SIZE = 16384 };
-
- FdOutStream::FdOutStream(int fd_, bool blocking_, int timeoutms_, size_t bufSize_)
- : fd(fd_), blocking(blocking_), timeoutms(timeoutms_),
- bufSize(bufSize_ ? bufSize_ : DEFAULT_BUF_SIZE), offset(0)
- {
- ptr = start = sentUpTo = new U8[bufSize];
- end = start + bufSize;
-
- gettimeofday(&lastWrite, NULL);
- }
-
- FdOutStream::~FdOutStream()
- {
- try {
- blocking = true;
- flush();
- } catch (Exception&) {
- }
- delete [] start;
- }
-
- void FdOutStream::setTimeout(int timeoutms_) {
- timeoutms = timeoutms_;
- }
-
- void FdOutStream::setBlocking(bool blocking_) {
- blocking = blocking_;
- }
-
- size_t FdOutStream::length()
- {
- return offset + ptr - sentUpTo;
- }
-
- int FdOutStream::bufferUsage()
- {
- return ptr - sentUpTo;
- }
-
- unsigned FdOutStream::getIdleTime()
- {
- return rfb::msSince(&lastWrite);
- }
-
- void FdOutStream::flush()
- {
- while (sentUpTo < ptr) {
- size_t n = writeWithTimeout((const void*) sentUpTo,
- ptr - sentUpTo,
- blocking? timeoutms : 0);
-
- // Timeout?
- if (n == 0) {
- // If non-blocking then we're done here
- if (!blocking)
- break;
-
- throw TimedOut();
- }
-
- sentUpTo += n;
- offset += n;
- }
-
- // Managed to flush everything?
- if (sentUpTo == ptr)
- ptr = sentUpTo = start;
- }
-
-
- size_t FdOutStream::overrun(size_t itemSize, size_t nItems)
- {
- if (itemSize > bufSize)
- throw Exception("FdOutStream overrun: max itemSize exceeded");
-
- // First try to get rid of the data we have
- flush();
-
- // Still not enough space?
- if (itemSize > (size_t)(end - ptr)) {
- // Can we shuffle things around?
- // (don't do this if it gains us less than 25%)
- if (((size_t)(sentUpTo - start) > bufSize / 4) &&
- (itemSize < bufSize - (ptr - sentUpTo))) {
- memmove(start, sentUpTo, ptr - sentUpTo);
- ptr = start + (ptr - sentUpTo);
- sentUpTo = start;
- } else {
- // Have to get rid of more data, so turn off non-blocking
- // for a bit...
- bool realBlocking;
-
- realBlocking = blocking;
- blocking = true;
- flush();
- blocking = realBlocking;
- }
- }
-
- // Can we fit all the items asked for?
- if (itemSize * nItems > (size_t)(end - ptr))
- nItems = (end - ptr) / itemSize;
-
- return nItems;
- }
-
- //
- // writeWithTimeout() writes up to the given length in bytes from the given
- // buffer to the file descriptor. If there is a timeout set and that timeout
- // expires, it throws a TimedOut exception. Otherwise it returns the number of
- // bytes written. It never attempts to send() unless select() indicates that
- // the fd is writable - this means it can be used on an fd which has been set
- // non-blocking. It also has to cope with the annoying possibility of both
- // select() and send() returning EINTR.
- //
-
- size_t FdOutStream::writeWithTimeout(const void* data, size_t length, int timeoutms)
- {
- int n;
-
- do {
- fd_set fds;
- struct timeval tv;
- struct timeval* tvp = &tv;
-
- if (timeoutms != -1) {
- tv.tv_sec = timeoutms / 1000;
- tv.tv_usec = (timeoutms % 1000) * 1000;
- } else {
- tvp = NULL;
- }
-
- FD_ZERO(&fds);
- FD_SET(fd, &fds);
- n = select(fd+1, 0, &fds, 0, tvp);
- } while (n < 0 && errno == EINTR);
-
- if (n < 0)
- throw SystemException("select", errno);
-
- if (n == 0)
- return 0;
-
- do {
- // select only guarantees that you can write SO_SNDLOWAT without
- // blocking, which is normally 1. Use MSG_DONTWAIT to avoid
- // blocking, when possible.
- #ifndef MSG_DONTWAIT
- n = ::send(fd, (const char*)data, length, 0);
- #else
- n = ::send(fd, (const char*)data, length, MSG_DONTWAIT);
- #endif
- } while (n < 0 && (errno == EINTR));
-
- if (n < 0)
- throw SystemException("write", errno);
-
- gettimeofday(&lastWrite, NULL);
-
- return n;
- }
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