用C為L(zhǎng)UA寫一個(gè)超迷你的模板引擎.
中午在做HTTP服務(wù)器,內(nèi)嵌了LUA引擎作為業(yè)務(wù)邏輯部分. 但考慮到LUA輸出HTML的性能不高,況且 MVC 模式開發(fā)網(wǎng)頁(yè)已經(jīng)習(xí)慣了,何不用C給lua寫個(gè)最簡(jiǎn)單的模板引擎呢?說(shuō)做就做, 項(xiàng)目時(shí)間很緊張,所以必須確定目標(biāo),想了會(huì)兒。定了幾個(gè)目標(biāo):
我要的是編譯型的模板,要支持緩存。
不需要強(qiáng)大的模板邏輯方面的指令。將HTML模板文件編譯成LUA源代碼即可。LUA 還是比較容易擴(kuò)展的,除了那棧用起來(lái)比較變態(tài)之外,經(jīng)過(guò)了幾個(gè)小時(shí)的奮斗,C+LUA代碼。算是大功告成了。
#include#include#include#include#include#include#include#include?"lib/automem.h" #include?"lua.h" #include?"lauxlib.h" #include?"lua-tpl.h" /* LUA?最簡(jiǎn)單的模板引擎. */ const?char?LUAFMT_TPL_META[]="LUAFMT_TPL"; void?lua_cfmt_createmetatable?(lua_State?*L); void?lua_register_class(lua_State?*?L,const?luaL_Reg?*?methods,const?char?*?name,lua_CFunction?has_index); #if?defined(_WIN32)?||?defined(_WIN64) #define?open _open #define?close _close #define?read _read #define?stat(?x?,?y?) _stat(?x?,?y?) #endif static?char?*?file_get_contents(const?char?*?file,int?*?sz){ char?*?ret?=?NULL; struct?stat?st; int?fd; *sz?=?0; if?((fd?=?open(file,?O_RDONLY|O_BINARY))?!=?-1) { if?(fstat(fd,?&st)?!=?-1) { ret?=?(char?*)malloc(st.st_size); if(NULL?!=?ret){ while(?*sz?<?st.st_size){ *sz?+=?read(fd,?ret?+?*sz,?st.st_size?-?(*sz)); _lseek(fd,?*sz,?SEEK_SET); } } close(fd); } } return?ret; } int?file_put_contents(const?char*?file_name,?automem_t*?mem) { FILE?*?fp?=?fopen(file_name,"wb+"); if(NULL?!=?fp) { fwrite(mem->pdata,?mem->size,?1,?fp); fclose(fp); return?1; } return?0; } enum{ tpl_state_normal, tpl_state_scode_1, tpl_state_code, tpl_state_ecode_1, tpl_state_escape, }; #define?append_end_stringfield(a,b,c)? automem_append_voidp(?(a)?,?cmd,?lcmd);? automem_append_voidp(?(a),?(b)?,?(c));? automem_append_voidp(?(a)?,?ecmd,?lecmd);? automem_append_voidp(?(a),?")n",?2); static?void?lua_tpl_compile_local(lua_State?*?L,?automem_t?*?mem,?const?char?*?buf,int?lbuf){ int?state?=?tpl_state_normal,?i?=?0; const?char?*?sbuf;?char?c; size_t?lcmd?=?sizeof("request.print([[")?-1, lecmd?=?sizeof("]])")?-1, lpre?=?0; const?char?*?cmd?=?"request.print([[", *?ecmd?=?"]])", *pre?=?NULL; if(lua_isstring(L,?3)) cmd?=luaL_checklstring(L,?3,?&lcmd); if(lua_isstring(L,?4)) ecmd?=luaL_checklstring(L,?4,?&lecmd); if(lua_isstring(L,?5)) pre?=luaL_checklstring(L,?5,?&lpre); if(NULL?!=?pre){ automem_append_voidp(mem,?pre,?lpre); automem_append_byte(mem,'n'); } sbuf?=?buf; while(i?<?lbuf){ c?=?buf[i]; switch?(state) { case?tpl_state_normal: switch(c){ case?'{': state?=?tpl_state_scode_1; break; } break; case?tpl_state_scode_1: switch(c){ case?'#': state?=tpl_state_code; append_end_stringfield(mem,sbuf,?&buf[i]?-?sbuf-1); sbuf?=?&buf[i+1]; break; default: state?=?tpl_state_normal; break; } break; case?tpl_state_code: switch(c){ case?'#': state?=?tpl_state_ecode_1; break; } case?tpl_state_ecode_1: switch(c){ case?'}': automem_append_voidp(mem,sbuf,?&buf[i]?-?sbuf-1); automem_append_byte(mem,'n'); sbuf?=?&buf[i+1]; state?=?tpl_state_normal; break; default: state=tpl_state_code; } default: break; } i++; } if(tpl_state_normal?==?state){ append_end_stringfield(mem,sbuf,?&buf[i]?-?sbuf); } } /*?對(duì)模板文件進(jìn)行編譯.*/ static?int?lua_tpl_compile(lua_State?*?L) { int?cache?=?0,i?=?0,?lbuf?=?0; size_t?lfile; const?char?*cfile?=?NULL,?*?file=?luaL_checklstring(L,?1,&lfile),*?buf; automem_t?mem; if(lua_isboolean(L,?2)) cache?=lua_toboolean(L,?2); if(0?!=?cache){ struct?stat?st1,st2; cfile=(char?*)malloc(lfile+5); memcpy((char?*)cfile,file,lfile); strcpy((char?*)cfile+lfile,".tpl"); if((0?==?stat(file,&st1))?&&?(0?==?stat(cfile,?&st2))) { if(st1.st_mtime?<=?st2.st_mtime) { if(NULL?!=?(buf?=?file_get_contents(cfile,?&lbuf))) { free((void?*)cfile); lua_pushlstring(L,buf,?lbuf); goto?lua_tpl_compile_final; } } } } if(NULL?!=?(buf?=?file_get_contents(file,?&lbuf))) { automem_init(&mem,lbuf?+?1024); lua_tpl_compile_local(L,?&mem,?buf,?lbuf); free((void*)buf); lua_pushlstring(L,(char?*)mem.pdata,mem.size); if(0?!=?cache?&&?NULL?!=cfile) file_put_contents(cfile,&mem); automem_uninit(&mem); } if(NULL?!=?cfile) free((void?*)cfile); lua_tpl_compile_final: return?1; } static?luaL_Reg?fmt_tpl_reg[]?=?{ {"compile",lua_tpl_compile}, {NULL,NULL} }; int?luaopen_cfmt_tpl(lua_State?*?L) { luaL_newlib(L,?fmt_tpl_reg); lua_cfmt_createmetatable(L); return?1; }
整個(gè)LUA模塊擴(kuò)展就1個(gè)函數(shù) compile()。在LUA中的原型如下:
string??compile(filePath,cached,?write,?prefix,suffix,init)
功能: 將html模板編譯為lua代碼.
參數(shù):
filePath: html源文件的路徑.cached: 是否需要緩存.writer: 內(nèi)容輸出函數(shù)名.prefix: 文件分界符前綴.init:初始代碼,用于做參數(shù)展開之類的工作.
當(dāng)然,光有C的接口還不夠,為了使它變得簡(jiǎn)單易用,還需要用LUA對(duì)其包裝一下^_^, 包裝代碼如下:
function?util.tpl(writer) local?t?=??require?"cfmt.tpl" local?tpl?=?{} local?args?=?{} local?_prefix='[=[' local?_suffix=']=]' --?創(chuàng)建的時(shí)候指定?writer if?nil?~=?writer?then?args['_']=writer?end function?tpl:assign(name,value) args[name]=value end function?tpl:boundary(prefix,?suffix)?--修改字符串邊界符 if?nil?~=?prefix?then?_prefix=prefix?end if?nil?~=?suffix?then?_suffix=suffix?end end function?tpl:display(tpl,cache,writer)?--?tpl?模板文件位置,?cache?是否需要緩存?writer?可選,如果創(chuàng)建對(duì)象的時(shí)候指定了的話. local?i=1 if?nil~=writer?then?args['_']=writer?end local?init?=?{'local?args?=?...'} for?key,val?in?pairs(args)?do init[#init+1]='local?'..key..'=args["'..key..'"]' i=i+1 end init?=?table.concat(init,'n') local?code?=t.compile(tpl,cache,'_('.._prefix,?_suffix,init) load(code)(args) end return?tpl; end
接下來(lái)用起來(lái)就簡(jiǎn)單多了,上測(cè)試代碼.
---外部進(jìn)來(lái)的數(shù)據(jù)在這里做檢測(cè) function?login:request(r) local?tpl?=?(require?"util").tpl(r.print) local?users?={ {['ID']=1,['username']='bywayboy',['age']=31}, {['ID']=1,['username']='liigo',['age']=31}, {['ID']=1,['username']='sunwei',['age']=8}, } local?b={['a']=12} tpl:assign('users',users); tpl:assign('title',"測(cè)試模板變量.") tpl:assign('name',"某某童鞋") tpl:display("D:\VC\CmdChannel\win32\Debug\test.html",true) end
再來(lái)一個(gè)模板文件示例:
{#_(title)#}--方121212法ID姓名年齡{#?for?key,val?in?pairs(users)?do#}{#_(val['ID'])?#}{#_(val['username'])#}{#_(val['age'])#}{#end#}{#_(name)#}
該文件最終生成的緩存文件為:
local?args?=?... local?_=args["_"] local?name=args["name"] local?users=args["users"] local?title=args["title"] _([=[]=]) _(title) _([=[--方121212法ID姓名年齡]=]) ?for?key,val?in?pairs(users)?do _([=[]=]) _(val['ID'])? _([=[]=]) _(val['username']) _([=[]=]) _(val['age']) _([=[]=]) end _([=[]=]) _(name) _([=[]=])
輸出結(jié)果如圖:
最終生成的HTML代碼如下:
測(cè)試模板變量.--方121212法ID姓名年齡1bywayboy311liigo311sunwei8某某童鞋