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//
// Copyright (C) 2004-2008 Maciej Sobczak, Stephen Hutton
// Distributed under the Boost Software License, Version 1.0.
// (See accompanying file LICENSE_1_0.txt or copy at
// https://www.boost.org/LICENSE_1_0.txt)
//
#ifndef SOCI_BLOB_H_INCLUDED
#define SOCI_BLOB_H_INCLUDED
#include "soci/soci-platform.h"
// std
#include <cstddef>
#include <memory>
namespace soci
{
// basic blob operations
class session;
namespace details
{
class blob_backend;
} // namespace details
class SOCI_DECL blob
{
public:
// Creates an invalid blob object
blob() = default;
explicit blob(session & s);
~blob();
blob(blob &&other) = default;
blob &operator=(blob &&other) = default;
// Checks whether this blob is in a valid state
bool is_valid() const;
// (Re)initializes this blob
void initialize(session &s);
void initialize(details::blob_backend *backend);
std::size_t get_len();
// offset is backend-specific
[[deprecated("Use read_from_start instead")]]
std::size_t read(std::size_t offset, void * buf, std::size_t toRead);
// Extracts data from this blob into the given buffer.
// At most toRead bytes are extracted (and copied into buf).
// The amount of actually read bytes is returned.
//
// Note: Using an offset > 0 on a blob whose size is less than
// or equal to offset, will throw an exception.
std::size_t read_from_start(void * buf, std::size_t toRead,
std::size_t offset = 0);
// offset is backend-specific
[[deprecated("Use write_from_start instead")]]
std::size_t write(std::size_t offset, const void * buf,
std::size_t toWrite);
// offset starts from 0
std::size_t write_from_start(const void * buf, std::size_t toWrite,
std::size_t offset = 0);
std::size_t append(const void * buf, std::size_t toWrite);
void trim(std::size_t newLen);
details::blob_backend * get_backend() { return backEnd_.get(); }
private:
SOCI_NOT_COPYABLE(blob)
std::unique_ptr<details::blob_backend> backEnd_;
void ensure_initialized();
};
} // namespace soci
#endif
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