No2:luacom中文内容输出BUG及修正

使 用cell.Value2输出中文内容时总是乱码。怀疑是utf-8的原因，转换后结果仍然是乱码。自己再写个转换的再测试，依然是乱码，莫非有BUG！？ 下个LUACOM的源码，查看函数 tLuaCOMTypeHandler::com2lua 和 tStringBuffer tUtil::bstr2string 。整个过程看起来

    使用cell.Value2输出中文内容时总是乱码。怀疑是utf-8的原因，转换后结果仍然是乱码。自己再写个转换的再测试，依然是乱码，莫非有BUG！？

下个LUACOM的源码，查看函数tLuaCOMTypeHandler::com2lua和tStringBuffer tUtil::bstr2string。整个过程看起来都OK，但再测试发现，结果字符串少了一个bytes。

    在tLuaCOMTypeHandler::com2lua VT_BSTR分支中返回结果恰好是减去1，将其修改

lua_pushlstring(L, str, str.getSize()-1);修改为lua_pushlstring(L, str, str.getSize());

    重新编译LUACOM，再看cell.Value2输出结果，终于正确了。由于没进行全面测试，不知道其此修改会不会引入错误。资源里有个已经编译好的。

--lc是从网上抄来的unicode utf-8 ansi相互转换的函数

package.cpath=[[C:\Program Files\Lua\5.1\clibs\?.dll;d:\loonlib\sample\lc\?.dll]]
require "luacom"
require "lc"

function print_table(t) for k,v in pairs(t) do print(k,v) end end
excel = luacom.CreateObject("Excel.Application")
excel.Visible = true
excel.Workbooks:Add();
--luacom.ViewTypeLib(excel);
sheet=excel.Sheets(1);
local r=sheet:Range("E6");

local s = "严中";
ws, s2=lc.a2w(s); --0x25 0x4e 0x2d 0x4e 0x00 0x00 6
print("unicode : " .. lc.bstr(ws, s2));
us, s2=lc.w2u(ws, s2); --0xe4 0xb8 0xa5 0xe4 0xb8 0xad 0x00 0x00 8
print("utf8 : " .. lc.bstr(us, s2));

r.Value2=us;
ws, s2=lc.u2w(r.Value2, s2);
print("unicode : " .. lc.bstr(ws, s2));
as, s2=lc.w2a(ws, s2);
print("ansi : " .. lc.bstr(as, s2));
print(as);

lc.def

LIBRARY	"lc"

EXPORTS
	luaopen_lc

lc.h

extern "C" {
#include "lua.h"
#include "lualib.h" 
#include "lauxlib.h"
int luaopen_local(lua_State* L);
}

#include 
#include 
#ifdef WIN32
#include 
#include 
#else
#include 
#endif


#define LN_lc "lc"
int lua_a2w(lua_State* L);
int lua_u2w(lua_State* L);
int lua_w2a(lua_State* L);
int lua_w2u(lua_State* L);
int lua_u2a(lua_State* L);
int lua_a2u(lua_State* L);
int lua_bstr(lua_State* L);

int lua_help(lua_State* L);
wchar_t* mb2wc(const char* mbstr, int& s2, int cp);
char* wc2mb(const wchar_t* wcstr, int& s2, int cp);

lc.cpp

#include "lc.h"
//g++ -shared -s -o lc.dll -O3 lc.cpp lc.def -llua5.1 -DWIN32 -I%loon%/lua/src -L%loon%/lib/gcc_dll/debug -Wl,--out-implib,liblc.a 

int lua_bstr(lua_State* L) {
	const char* s = luaL_optstring(L, 1, "");
	int len = luaL_optnumber(L, 2, 0);
	if (strcmp(s, "")==0 || 0==len) {
		lua_pushstring(L, s);
	} else {
		luaL_Buffer b;
		luaL_buffinit(L, &b);
		char* byte = (char*)malloc(64);
		for (int i=0; i0) {
		int s2 = 0;
		wchar_t* wcstr = mb2wc(mbstr, s2, CP_UTF8);
		if (wcstr) {
			lua_pushlstring(L, (const char*)wcstr, s2);
			lua_pushnumber(L, s2);
			delete[] wcstr;
			result = 2;
		}
	}
	return result;
}

int lua_a2w(lua_State* L) {
	int result = 0;
	size_t len = 0;
	const char* mbstr = lua_tolstring(L, 1, &len);
	if (mbstr && len>0) {
		int s2 = 0;
		wchar_t* wcstr = mb2wc(mbstr, s2, CP_ACP);
		if (wcstr) {
			lua_pushlstring(L, (const char*)wcstr, s2);
			lua_pushnumber(L, s2);
			delete[] wcstr;
			result = 2;
		}
	}
	return result;
}

int lua_w2a(lua_State* L) {
	int result = 0;
	size_t len = 0;
	const char* wcstr = lua_tolstring(L, 1, &len);
	if (wcstr && len>0) {
		int s2 = 0;
		char* mbstr = wc2mb((wchar_t*)wcstr, s2, CP_ACP);
		if (mbstr) {
			lua_pushlstring(L, mbstr, s2);
			lua_pushnumber(L, s2);
			delete[] mbstr;
			result = 2;
		}
	}
	return result;
}

int lua_w2u(lua_State* L) {
	int result = 0;
	size_t len = 0;
	const char* wcstr = lua_tolstring(L, 1, &len);
	if (wcstr && len>0) {
		int s2 = 0;
		char* mbstr = wc2mb((wchar_t*)wcstr, s2, CP_UTF8);
		if (mbstr) {
			lua_pushlstring(L, mbstr, s2);
			lua_pushnumber(L, s2);
			delete[] mbstr;
			result = 2;
		}
	}
	return result;
}

int lua_u2a(lua_State* L) {
	int result = 0;
	size_t len = 0;
	const char* mbstr = lua_tolstring(L, 1, &len);
	if (mbstr && len>0) {
		int s2 = 0;
		wchar_t* wcstr = mb2wc(mbstr, s2, CP_UTF8);
		if (wcstr) {
			char* nmbstr = wc2mb(wcstr, s2, CP_ACP);
			if (nmbstr) {
				lua_pushlstring(L, nmbstr, s2);
				lua_pushnumber(L, s2);
				result = 2;
				delete[] nmbstr;
			}
			delete[] wcstr;
		}
	}
	return result;
}

int lua_a2u(lua_State* L) {
	int result = 0;
	size_t len = 0;
	const char* mbstr = lua_tolstring(L, 1, &len);
	if (mbstr && len>0) {
		int s2 = 0;
		wchar_t* wcstr = mb2wc(mbstr, s2, CP_ACP);
		if (wcstr) {
			char* nmbstr = wc2mb(wcstr, s2, CP_UTF8);
			if (nmbstr) {
				lua_pushlstring(L, nmbstr, s2);
				lua_pushnumber(L, s2);
				result = 2;
				delete[] nmbstr;
			}
			delete[] wcstr;
		}
	}
	return result;
}

wchar_t* mb2wc(const char* mbstr, int& s2, int cp) {
	wchar_t* wcstr = NULL;
#ifdef WIN32
	int size = MultiByteToWideChar(cp, 0, mbstr, -1, NULL, 0);
#else
	size_t size = mbstowcs(NULL, mbstr, 0);
#endif
	wcstr = new wchar_t[size];
	if (wcstr) {
		memset(wcstr, 0, size * sizeof(wchar_t));
#ifdef WIN32
		int ret = MultiByteToWideChar(cp, 0, mbstr, -1, wcstr, size);
		if (ret == 0) { // MultiByteToWideChar returns 0 if it does not succeed.
#else
		size_t ret = mbstowcs(wcstr, mbstr, size+1);
		if (ret == -1) {
#endif
			delete[] wcstr;
			wcstr = NULL;
		}
		s2 = 2*size;
	}
	return wcstr;
}

char* wc2mb(const wchar_t* wcstr, int& s2, int cp) {
	char* mbstr = NULL;
#ifdef WIN32
	int size = WideCharToMultiByte(cp, 0, wcstr, -1, NULL, 0, NULL, NULL);
#else
	size_t size = wcstombs(NULL, wcstr, 0);
#endif
	mbstr = new char[size];
	if (mbstr) {
		memset(mbstr, 0, size * sizeof(char));
#ifdef WIN32
		int ret = WideCharToMultiByte(cp, 0, wcstr, -1, mbstr, size, NULL, NULL);
		if (ret == 0) { // MultiByteToWideChar returns 0 if it does not succeed.
#else
		size_t ret = wcstombs(mbstr, wcstr, size+1);
		if (ret == -1) {
#endif
			delete[] mbstr;
			mbstr = NULL;
		}
		s2 = size;
	}
	return mbstr;
}

int lua_help(lua_State* L) {
	const char* s= 
		"Simple Characters Transformation\n"
		"  a2w(ansi to unicode)\n"
		"  u2w(utf8 to unicode)\n"
		"  w2a(unicode to ansi)\n"
		"  w2u(unicode to utf8)\n"
		"  u2a(utf8 to ansi)\n"
		"  a2u(ansi to utf8)\n"
		"  bstr(bytes of str)\n"
		"  help(show this)\n\n"
		"  example :\n"
		"    local s = \"I like lua\"\n"
		"    print(lc.bstr(s, string.len(s)+1))\n"
		"    local ws, s2 = lc.a2w(s)\n"
		"wunoman@qq.com 2012/03/06\n"
		;
	lua_pushstring(L, s);

	return 1;
}

luaL_reg lrg_lc[] = {
	{"a2w", lua_a2w},
	{"u2w", lua_u2w},
	{"w2a", lua_w2a},
	{"w2u", lua_w2u},
	{"u2a", lua_u2a},
	{"a2u", lua_a2u},
	{"bstr", lua_bstr},
	{"help", lua_help},
    {NULL, NULL}
};

extern "C" int luaopen_lc(lua_State* L) {
    luaL_register(L, LN_lc, lrg_lc);
	return 1;
}