mirror of
https://github.com/qgis/QGIS.git
synced 2025-02-23 00:02:38 -05:00
320 lines
7.9 KiB
C++
320 lines
7.9 KiB
C++
/******************************************************************************
|
|
* Copyright (c) 2014, Hobu Inc., hobu@hobu.co
|
|
*
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following
|
|
* conditions are met:
|
|
*
|
|
* * Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* * Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in
|
|
* the documentation and/or other materials provided
|
|
* with the distribution.
|
|
* * Neither the name of Hobu, Inc. or Flaxen Geo Consulting nor the
|
|
* names of its contributors may be used to endorse or promote
|
|
* products derived from this software without specific prior
|
|
* written permission.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
|
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
|
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
|
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
|
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
|
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
|
|
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
|
|
* OF SUCH DAMAGE.
|
|
****************************************************************************/
|
|
|
|
#pragma once
|
|
|
|
#include <cstring>
|
|
#include <vector>
|
|
|
|
#include "portable_endian.hpp"
|
|
|
|
namespace lazperf
|
|
{
|
|
|
|
/**
|
|
Buffer wrapper for input of binary data from a buffer.
|
|
*/
|
|
class LeExtractor
|
|
{
|
|
public:
|
|
/**
|
|
Construct an extractor to operate on a buffer.
|
|
|
|
\param buf Buffer to extract from.
|
|
\param size Buffer size.
|
|
*/
|
|
LeExtractor(const char *buf, std::size_t size) : m_eback(buf),
|
|
m_egptr(buf + size), m_gptr(buf)
|
|
{}
|
|
|
|
private:
|
|
const char *m_eback; ///< Start of the buffer (name from std::streambuf)
|
|
const char *m_egptr; ///< End of the buffer.
|
|
const char *m_gptr; ///< Current get position.
|
|
|
|
public:
|
|
/**
|
|
Determine if the buffer is good.
|
|
|
|
\return Whether the buffer is good.
|
|
*/
|
|
operator bool ()
|
|
{ return good(); }
|
|
|
|
/**
|
|
Seek to a position in the buffer.
|
|
|
|
\param pos Position to seek in buffer.
|
|
*/
|
|
void seek(std::size_t pos)
|
|
{ m_gptr = m_eback + pos; }
|
|
|
|
/**
|
|
Advance buffer position.
|
|
|
|
\param cnt Number of bytes to skip in buffer.
|
|
*/
|
|
void skip(std::size_t cnt)
|
|
{ m_gptr += cnt; }
|
|
|
|
/**
|
|
Return the get position of buffer.
|
|
|
|
\return Get position.
|
|
*/
|
|
size_t position() const
|
|
{ return m_gptr - m_eback; }
|
|
|
|
/**
|
|
Determine whether the extractor is good (the get pointer is in the
|
|
buffer).
|
|
|
|
\return Whether the get pointer is valid.
|
|
*/
|
|
bool good() const
|
|
{ return m_gptr < m_egptr; }
|
|
|
|
/**
|
|
Extract a string of a particular size from the buffer. Trim trailing
|
|
null bytes.
|
|
|
|
\param s String to extract to.
|
|
\param size Number of bytes to extract from buffer into string.
|
|
*/
|
|
void get(std::string& s, size_t size)
|
|
{
|
|
s = std::string(m_gptr, size);
|
|
m_gptr += size;
|
|
while (size)
|
|
{
|
|
size--;
|
|
if (s[size] != '\0')
|
|
{
|
|
s.resize(size + 1);
|
|
return;
|
|
}
|
|
}
|
|
s.clear();
|
|
}
|
|
|
|
/**
|
|
Extract data to char vector. Vector must be sized to indicate
|
|
number of bytes to extract.
|
|
|
|
\param buf Vector to which bytes should be extracted.
|
|
*/
|
|
void get(std::vector<char>& buf)
|
|
{
|
|
memcpy((char *)buf.data(), m_gptr, buf.size());
|
|
m_gptr += buf.size();
|
|
}
|
|
|
|
/**
|
|
Extract data to unsigned char vector. Vector must be sized to
|
|
indicate number of bytes to extract.
|
|
|
|
\param buf Vector to which bytes should be extracted.
|
|
*/
|
|
void get(std::vector<unsigned char>& buf)
|
|
{
|
|
memcpy((char *)buf.data(), m_gptr, buf.size());
|
|
m_gptr += buf.size();
|
|
}
|
|
|
|
/**
|
|
Extract data into a provided buffer.
|
|
|
|
\param buf Pointer to buffer to which bytes should be extracted.
|
|
\param size Number of bytes to extract.
|
|
*/
|
|
void get(char *buf, size_t size)
|
|
{
|
|
memcpy(buf, m_gptr, size);
|
|
m_gptr += size;
|
|
}
|
|
|
|
/**
|
|
Extract data into a provided unsigned buffer.
|
|
|
|
\param buf Pointer to buffer to which bytes should be extracted.
|
|
\param size Number of bytes to extract.
|
|
*/
|
|
void get(unsigned char *buf, size_t size)
|
|
{
|
|
memcpy(buf, m_gptr, size);
|
|
m_gptr += size;
|
|
}
|
|
|
|
/**
|
|
Extract an unsigned byte from a buffer.
|
|
|
|
\param v Unsigned byte to extract to.
|
|
\return This extractor.
|
|
*/
|
|
LeExtractor& operator >> (uint8_t& v)
|
|
{
|
|
v = *(const uint8_t *)m_gptr++;
|
|
return *this;
|
|
}
|
|
|
|
/**
|
|
Extract a byte from a buffer.
|
|
|
|
\param v Byte to extract to.
|
|
\return This extractor.
|
|
*/
|
|
LeExtractor& operator >> (int8_t& v)
|
|
{
|
|
v = *(const int8_t *)m_gptr++;
|
|
return *this;
|
|
}
|
|
|
|
/**
|
|
Extract an unsgined short from a buffer.
|
|
|
|
\param v Short to extract to.
|
|
\return This extractor.
|
|
*/
|
|
LeExtractor& operator >> (uint16_t& v)
|
|
{
|
|
memcpy(&v, m_gptr, sizeof(v));
|
|
v = le16toh(v);
|
|
m_gptr += sizeof(v);
|
|
return *this;
|
|
}
|
|
|
|
/**
|
|
Extract a short from a buffer.
|
|
|
|
\param v Short to extract to.
|
|
\return This extractor.
|
|
*/
|
|
LeExtractor& operator >> (int16_t& v)
|
|
{
|
|
memcpy(&v, m_gptr, sizeof(v));
|
|
v = (int16_t)le16toh((uint16_t)v);
|
|
m_gptr += sizeof(v);
|
|
return *this;
|
|
}
|
|
|
|
/**
|
|
Extract an unsigned int from a buffer.
|
|
|
|
\param v Unsigned int to extract to.
|
|
\return This extractor.
|
|
*/
|
|
LeExtractor& operator >> (uint32_t& v)
|
|
{
|
|
memcpy(&v, m_gptr, sizeof(v));
|
|
v = le32toh(v);
|
|
m_gptr += sizeof(v);
|
|
return *this;
|
|
}
|
|
|
|
/**
|
|
Extract an int from a buffer.
|
|
|
|
\param v int to extract to.
|
|
\return This extractor.
|
|
*/
|
|
LeExtractor& operator >> (int32_t& v)
|
|
{
|
|
memcpy(&v, m_gptr, sizeof(v));
|
|
v = (int32_t)le32toh((uint32_t)v);
|
|
m_gptr += sizeof(v);
|
|
return *this;
|
|
}
|
|
|
|
/**
|
|
Extract an unsigned long int from a buffer.
|
|
|
|
\param v unsigned long int to extract to.
|
|
\return This extractor.
|
|
*/
|
|
LeExtractor& operator >> (uint64_t& v)
|
|
{
|
|
memcpy(&v, m_gptr, sizeof(v));
|
|
v = le64toh(v);
|
|
m_gptr += sizeof(v);
|
|
return *this;
|
|
}
|
|
|
|
/**
|
|
Extract a long int from a buffer.
|
|
|
|
\param v long int to extract to.
|
|
\return This extractor.
|
|
*/
|
|
LeExtractor& operator >> (int64_t& v)
|
|
{
|
|
memcpy(&v, m_gptr, sizeof(v));
|
|
v = (int64_t)le64toh((uint64_t)v);
|
|
m_gptr += sizeof(v);
|
|
return *this;
|
|
}
|
|
|
|
/**
|
|
Extract a float from a buffer.
|
|
|
|
\param v float to extract to.
|
|
\return This extractor.
|
|
*/
|
|
LeExtractor& operator >> (float& v)
|
|
{
|
|
memcpy(&v, m_gptr, sizeof(v));
|
|
uint32_t tmp = le32toh(*(uint32_t *)(&v));
|
|
memcpy(&v, &tmp, sizeof(tmp));
|
|
m_gptr += sizeof(v);
|
|
return *this;
|
|
}
|
|
|
|
/**
|
|
Extract a double from a buffer.
|
|
|
|
\param v double to extract to.
|
|
\return This extractor.
|
|
*/
|
|
LeExtractor& operator >> (double& v)
|
|
{
|
|
memcpy(&v, m_gptr, sizeof(v));
|
|
uint64_t tmp = le64toh(*(uint64_t *)(&v));
|
|
memcpy(&v, &tmp, sizeof(tmp));
|
|
m_gptr += sizeof(v);
|
|
return *this;
|
|
}
|
|
};
|
|
|
|
} // namespace lazperf
|
|
|