/strigi-0.7.7/libstreams/lib/subinputstream.cpp
C++ | 125 lines | 94 code | 2 blank | 29 comment | 34 complexity | f4043f57a0b1df8f7181160bc77e98d7 MD5 | raw file
Possible License(s): LGPL-2.0
- /* This file is part of Strigi Desktop Search
- *
- * Copyright (C) 2006 Jos van den Oever <jos@vandenoever.info>
- *
- * 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 <strigi/subinputstream.h>
- #include <strigi/strigiconfig.h>
- #include <iostream>
- #include <cassert>
- using namespace std;
- using namespace Strigi;
- SubInputStream::SubInputStream(InputStream *i, int64_t length)
- : m_offset(i->position()), m_input(i) {
- assert(length >= -1);
- // fprintf(stderr, "substream m_offset: %li\n", m_offset);
- m_size = length;
- }
- int32_t
- SubInputStream::read(const char*& start, int32_t min, int32_t max) {
- if (m_size != -1) {
- const int64_t left = m_size - m_position;
- if (left == 0) {
- m_status = Eof;
- return -1;
- }
- // restrict the amount of data that can be read
- if (min > left) min = (int32_t)left;
- if (max < min || max > left) {
- max = (int32_t)left;
- }
- }
- int32_t nread = m_input->read(start, min, max);
- assert(max < min || nread <= max);
- if (nread < -1) {
- fprintf(stderr, "substream too short.\n");
- m_status = Error;
- m_error = m_input->error();
- } else if (nread < min) {
- if (m_size == -1) {
- m_status = Eof;
- if (nread > 0) {
- m_position += nread;
- m_size = m_position;
- }
- } else {
- // fprintf(stderr, "!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! nread %i min %i max %i m_size %li\n", nread, min, max, m_size);
- // fprintf(stderr, "pos %li parentpos %li\n", m_position, m_input->position());
- // fprintf(stderr, "status: %i error: %s\n", m_input->status(), m_input->error());
- // we expected data but didn't get enough so that's an error
- m_status = Error;
- m_error = "Premature end of stream\n";
- nread = -2;
- }
- } else {
- m_position += nread;
- if (m_position == m_size) {
- m_status = Eof;
- }
- }
- return nread;
- }
- int64_t
- SubInputStream::reset(int64_t newpos) {
- assert(newpos >= 0);
- // fprintf(stderr, "subreset pos: %li newpos: %li m_offset: %li m_size: %li\n",
- // m_position, newpos, m_offset, m_size);
- m_position = m_input->reset(newpos + m_offset);
- if (m_position < m_offset) {
- cerr << "########### m_position " << m_position << " newpos " << newpos
- << endl;
- m_status = Error;
- m_error = m_input->error();
- } else {
- m_position -= m_offset;
- m_status = m_input->status();
- }
- return m_position;
- }
- int64_t
- SubInputStream::skip(int64_t ntoskip) {
- // fprintf(stderr, "subskip pos: %li ntoskip: %li m_offset: %li m_size: %li\n", m_position, ntoskip, m_offset, m_size);
- if (m_size == m_position) {
- m_status = Eof;
- return -1;
- }
- if (ntoskip == 0) return 0;
- if (m_size != -1) {
- const int64_t left = m_size - m_position;
- // restrict the amount of data that can be skipped
- if (ntoskip > left) {
- ntoskip = left;
- }
- }
- int64_t skipped = m_input->skip(ntoskip);
- if (m_input->status() == Error) {
- m_status = Error;
- m_error = m_input->error();
- } else {
- m_position += skipped;
- if (m_position == m_size) {
- m_status = Eof;
- } else if (skipped <= 0) {
- m_status = Error;
- m_error = "Premature end of stream\n";
- skipped = -2;
- }
- }
- return skipped;
- }