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- #include "DoubleBuffer.h"
- void DoubleBuffer::flip()
- {
- InterruptDisabler disabler;
- ASSERT(m_read_buffer_index == m_read_buffer->size());
- swap(m_read_buffer, m_write_buffer);
- if (m_write_buffer->capacity() < 32)
- m_write_buffer->clear_with_capacity();
- else
- m_write_buffer->clear();
- m_read_buffer_index = 0;
- }
- ssize_t DoubleBuffer::write(const byte* data, size_t size)
- {
- m_write_buffer->append(data, size);
- return size;
- }
- ssize_t DoubleBuffer::read(byte* data, size_t size)
- {
- if (m_read_buffer_index >= m_read_buffer->size() && !m_write_buffer->is_empty())
- flip();
- if (m_read_buffer_index >= m_read_buffer->size())
- return 0;
- ssize_t nread = min(m_read_buffer->size() - m_read_buffer_index, size);
- memcpy(data, m_read_buffer->data() + m_read_buffer_index, nread);
- m_read_buffer_index += nread;
- return nread;
- }
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