epee::net_utils::buffer Class Reference

#include <buffer.h>

Public Member Functions
	buffer (size_t reserve=0)
void	append (const void *data, size_t sz)
void	erase (size_t sz)
epee::span< const uint8_t >	span (size_t sz) const
epee::span< const uint8_t >	carve (size_t sz)
size_t	size () const

Detailed Description

Definition at line 45 of file buffer.h.

Constructor & Destructor Documentation

buffer()

epee::net_utils::buffer::buffer ( size_t reserve = 0 )

inline

Definition at line 48 of file buffer.h.

: offset(0) { storage.reserve(reserve); }

Member Function Documentation

append()

void epee::net_utils::buffer::append	(	const void *	data,
		size_t	sz )

Definition at line 40 of file buffer.cpp.

{
  const size_t capacity = storage.capacity();
  const size_t avail = capacity - storage.size();
 
  CHECK_AND_ASSERT_THROW_MES(storage.size() < std::numeric_limits<size_t>::max() - sz, "Too much data to append");
 
  // decide when to move
  if (sz > avail)
  {
    // we have to reallocate or move
    const bool move = size() + sz <= capacity;
    if (move)
    {
      const size_t bytes = storage.size() - offset;
      NET_BUFFER_LOG("appending " << sz << " from " << size() << " by moving " << bytes << " from offset " << offset << " first (forced)");
      memmove(storage.data(), storage.data() + offset, bytes);
      storage.resize(bytes);
      offset = 0;
    }
    else
    {
      NET_BUFFER_LOG("appending " << sz << " from " << size() << " by reallocating");
      std::vector<uint8_t> new_storage;
      size_t reserve = (((size() + sz) * 3 / 2) + 4095) & ~4095;
      new_storage.reserve(reserve);
      new_storage.resize(size());
      if (size() > 0)
        memcpy(new_storage.data(), storage.data() + offset, storage.size() - offset);
      offset = 0;
      std::swap(storage, new_storage);
    }
  }
  else
  {
    // we have space already
    if (size() <= 4096 && offset > 4096 * 16 && offset >= capacity / 2)
    {
      // we have little to move, and we're far enough into the buffer that it's probably a win to move anyway
      const size_t pos = storage.size() - offset;
      NET_BUFFER_LOG("appending " << sz << " from " << size() << " by moving " << pos << " from offset " << offset << " first (unforced)");
      memmove(storage.data(), storage.data() + offset, storage.size() - offset);
      storage.resize(pos);
      offset = 0;
    }
    else
    {
      NET_BUFFER_LOG("appending " << sz << " from " << size() << " by writing to existing capacity");
    }
  }
 
  // add the new data
  storage.insert(storage.end(), (const uint8_t*)data, (const uint8_t*)data + sz);
 
  NET_BUFFER_LOG("storage now " << offset << "/" << storage.size() << "/" << storage.capacity());
}

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carve()

epee::span< const uint8_t > epee::net_utils::buffer::carve ( size_t sz )

inline

Definition at line 54 of file buffer.h.

{ CHECK_AND_ASSERT_THROW_MES(sz <= size(), "span is too large"); offset += sz; return epee::span<const uint8_t>(storage.data() + offset - sz, sz); }

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erase()

void epee::net_utils::buffer::erase ( size_t sz )

inline

Definition at line 51 of file buffer.h.

{ NET_BUFFER_LOG("erasing " << sz << "/" << size()); CHECK_AND_ASSERT_THROW_MES(offset + sz <= storage.size(), "erase: sz too large"); offset += sz; if (offset == storage.size()) { storage.resize(0); offset = 0; } }

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size()

size_t epee::net_utils::buffer::size ( ) const

inline

Definition at line 55 of file buffer.h.

{ return storage.size() - offset; }

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span()

epee::span< const uint8_t > epee::net_utils::buffer::span ( size_t sz ) const

inline

Definition at line 52 of file buffer.h.

{ CHECK_AND_ASSERT_THROW_MES(sz <= size(), "span is too large"); return epee::span<const uint8_t>(storage.data() + offset, sz); }

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The documentation for this class was generated from the following files:

• /home/abuild/rpmbuild/BUILD/electroneum-5.1.3.1-build/electroneum-5.1.3.1/contrib/epee/include/net/buffer.h
• /home/abuild/rpmbuild/BUILD/electroneum-5.1.3.1-build/electroneum-5.1.3.1/contrib/epee/src/buffer.cpp