code_twain/sane/scanned_img.h

#pragma once
#include "s2t_api.h"
#include <vector>
#include <mutex>

class refer : public IRef
{
	volatile long ref_;

protected:
	refer();
	virtual ~refer();

	// IRef
public:
	COM_API_OVERRIDE(long, add_ref(void));
	COM_API_OVERRIDE(long, release(void));
};

class mapping_buf
{
	unsigned long long	bytes_;
	unsigned long long	offset_;
	unsigned int		page_size_;
	unsigned int		map_unit_;
	unsigned int		mapped_bytes_;
	HANDLE				map_;
	bool				is_mem_;
	unsigned char*		buf_;
	std::string			file_;
	bool				rmv_file_;

	void init_map(const char* file, unsigned long long size);
	void close(void);
	void map(void);
	void set_buffer(unsigned char*& buf, unsigned long long off, unsigned int* bytes);

public:
	mapping_buf();
	~mapping_buf();

public:
	unsigned char* allocate(const wchar_t* file, unsigned long long size = 0, bool force_file = false);
	unsigned char* buffer(unsigned long long off, unsigned int* bytes);
	bool save(const void* data, size_t* bytes, unsigned long long off);
	bool save(unsigned long long off, mapping_buf* mbuf, unsigned long long src_off = 0);
	int read(void* buf, size_t* bytes, unsigned long long off);
	void unmap();
	void set_remove_file_when_destroyed(bool rmv);
	const char* file(void);
	unsigned long long bytes(void);
	unsigned long long offset(void);
	unsigned int mapped_bytes(void);
};
class scanned_img : public IScanImg, virtual public refer
{
	SANE_Parameters head_;
	mapping_buf*	data_;
	int				dpi_;
	SANE_Handle		dev_;
	std::wstring	file_;
	unsigned int	header_size_;
	SANE_FinalImgFormat	fmt_;
	size_t				pal_size_;

	SANE_Image_Statu	status_;

	// 部分APP不会通过XferMech来设置传输模式，原来预先准备数据的方法不适合该场合
	// 为适应该场景，增加prepare_data_for_transfer接口，在真实读取数据之前调用，以准备恰当的数据
	bool				data_done_ = false;

	std::string file_header(SANE_ImageType type, float resolution);
	void do_result(twain_xfer xfer);
	void swap_rgb(void);

public:
	scanned_img(SANE_Handle dev, SANE_Parameters head, void* data, unsigned int len, int dpi, const wchar_t* tmp_file
				, twain_xfer xfer = TWAIN_XFER_Native, SANE_FinalImgFormat *fmt = NULL);

	void set_image_status(SANE_Image_Statu status);

protected:
	~scanned_img();

	// IRef
public:
	COM_API_OVERRIDE(long, add_ref(void));
	COM_API_OVERRIDE(long, release(void));

	// IScanImg
public:
	COM_API_OVERRIDE(int, width(void));
	COM_API_OVERRIDE(int, line_bytes(void));
	COM_API_OVERRIDE(int, height(void));
	COM_API_OVERRIDE(int, depth(void));
	COM_API_OVERRIDE(int, channel(void));
	COM_API_OVERRIDE(int, dpi(void));
	COM_API_OVERRIDE(SANE_Frame, type(void));
	COM_API_OVERRIDE(unsigned int, bytes(void));
	COM_API_OVERRIDE(unsigned int, header_size(void));
	COM_API_OVERRIDE(unsigned char*, data(unsigned long long off, unsigned int* bytes));
	COM_API_OVERRIDE(int, read(void* buf, size_t* bytes, unsigned long long off = 0));
	COM_API_OVERRIDE(const char*, file(void));
	COM_API_OVERRIDE(void, keep_file(bool keep));
	COM_API_OVERRIDE(void, copy_header(SANE_Parameters* head));
	COM_API_OVERRIDE(int, image_status(void));
	COM_API_OVERRIDE(size_t, get_bits_offset(void));

public:
	void prepare_data_for_transfer(twain_xfer xfer);
};

template<class T>
class safe_queue
{
	typedef struct _t_and_size
	{
		size_t		bytes;
		T			t;
	}TNS;
	std::mutex			lock_;
	std::vector<TNS>	queue_;
	size_t				bytes_;
	T					empty_;

public:
	safe_queue() : bytes_(0)
	{}
	virtual ~safe_queue()
	{}

public:
	size_t count(size_t* bytes = NULL)
	{
		std::lock_guard<std::mutex>	lock(lock_);

		if (bytes)
			*bytes = bytes_;

		return queue_.size();
	}
	bool save(T v, size_t bytes)
	{
		std::lock_guard<std::mutex>	lock(lock_);
		TNS	tns = { bytes, v };

		queue_.push_back(tns);
		bytes_ += bytes;

		return true;
	}
	T take(bool remove = true, void(__stdcall* first)(T) = NULL)
	{
		std::lock_guard<std::mutex>	lock(lock_);
		TNS t;

		if (queue_.size())
		{
			t = queue_[0];
			if (remove)
			{
				queue_.erase(queue_.begin());
				bytes_ -= t.bytes;
			}
			if (first)
				first(t.t);
		}
		else
			t.t = empty_;

		return t.t;
	}
	void clear(void(__stdcall* tfree)(T) = NULL)
	{
		std::lock_guard<std::mutex>	lock(lock_);

		if (tfree)
		{
			for (auto& v : queue_)
				tfree(v.t);
		}
		queue_.clear();
		bytes_ = 0;
	}
};

class safe_img_queue : public safe_queue<scanned_img*>
{
	static void __stdcall access_image(scanned_img* img);
	static void __stdcall free_image(scanned_img* img);

public:
	safe_img_queue();
	~safe_img_queue();

public:
	bool get_header(SANE_Parameters* header, size_t* bytes = NULL, int *dpi = NULL);
	void clear();
};

namespace local_trans
{
	std::string u2a(const wchar_t* unic, UINT cp = CP_ACP);
	std::wstring a2u(const char* asc, UINT cp = CP_ACP);

	std::wstring lang_trans_between_hz936(const wchar_t* in, bool from_hz = true);
	const char* __stdcall lang_trans_between_hz936(const char* in, bool from_hz, void* param);
}