diff options
Diffstat (limited to 'flow/pipebuffer.cpp')
-rw-r--r-- | flow/pipebuffer.cpp | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/flow/pipebuffer.cpp b/flow/pipebuffer.cpp new file mode 100644 index 0000000..5fb81fb --- /dev/null +++ b/flow/pipebuffer.cpp @@ -0,0 +1,166 @@ + /* + + Copyright (C) 2000 Stefan Westerfeld + + This library is free software; you can redistribute it and/or + modify it under the terms of the GNU Library General Public + License as published by the Free Software Foundation; either + version 2 of the License, or (at your option) any later version. + + This library 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 + Library General Public License for more details. + + You should have received a copy of the GNU Library General Public License + along with this library; see the file COPYING.LIB. If not, write to + the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, + Boston, MA 02110-1301, USA. + + */ + +#include "pipebuffer.h" +#include <assert.h> +#include <cstring> + +using namespace std; +using namespace Arts; + +PipeSegment::PipeSegment(long size, void *buffer) +{ + this->buffer = new char[size]; + this->currentpos = this->buffer; + memcpy(this->buffer,buffer,size); + + _remaining = size; +} + +PipeSegment::~PipeSegment() +{ + delete[] buffer; +} + +void *PipeSegment::data() +{ + return currentpos; +} + +long PipeSegment::remaining() +{ + return _remaining; +} + +void PipeSegment::skip(long count) +{ + _remaining -= count; + currentpos += count; + assert(_remaining >= 0); +} + +PipeBuffer::PipeBuffer() +{ + _size = 0; +} + +PipeBuffer::~PipeBuffer() +{ + clear(); +} + +void PipeBuffer::clear() +{ + while(segments.size() != 0) + { + PipeSegment *first = *segments.begin(); + delete first; + + segments.pop_front(); + } + _size = 0; +} + +void *PipeBuffer::peek(long size) +{ + while(!segments.empty()) + { + PipeSegment *first = *segments.begin(); + if(size <= first->remaining()) + return first->data(); + } + return 0; +} + +void PipeBuffer::skip(long size) +{ + while(!segments.empty() && size > 0) + { + PipeSegment *first = *segments.begin(); + + // if we have less data to skip than the first segment contains + if(size < first->remaining()) + { + // skip the data inside the segment + + _size -= size; + first->skip(size); + return; + } + else + { + // otherwise erase the first segment + + _size -= first->remaining(); + size -= first->remaining(); + + delete first; + segments.pop_front(); + } + } +} + +long PipeBuffer::read(long size, void *buffer) +{ + long readbytes = 0; + char *bptr = (char *)buffer; + + while(!segments.empty() && size > 0) + { + PipeSegment *first = *segments.begin(); + long readCnt = size; + if(readCnt > first->remaining()) readCnt = first->remaining(); + + memcpy(bptr,first->data(),readCnt); + + first->skip(readCnt); + size -= readCnt; + bptr += readCnt; + readbytes += readCnt; + + if(first->remaining() == 0) + { + delete first; + segments.pop_front(); + } + } + + _size -= readbytes; + return readbytes; +} + +long PipeBuffer::size() +{ + return _size; +} + +void PipeBuffer::write(long size, void *buffer) +{ + segments.push_back(new PipeSegment(size,buffer)); + _size += size; +} + +void PipeBuffer::unRead(long size, void *buffer) +{ + segments.push_front(new PipeSegment(size,buffer)); + _size += size; +} |