text: 
  #include "lprefix.h"
  
  
  #include <errno.h>
  #include <locale.h>
  #include <stdlib.h>
  #include <string.h>
  #include <time.h>
  
  #include "lua.h"
  
  #include "lauxlib.h"
  #include "lualib.h"
  
  static int lunar_month_days[] =
  {
    1887, 0x1694, 0x16aa, 0x4ad5, 0xab6, 0xc4b7, 0x4ae, 0xa56, 0xb52a,
    0x1d2a, 0xd54, 0x75aa, 0x156a, 0x1096d, 0x95c, 0x14ae, 0xaa4d, 0x1a4c, 0x1b2a, 0x8d55, 0xad4, 0x135a, 0x495d,
    0x95c, 0xd49b, 0x149a, 0x1a4a, 0xbaa5, 0x16a8, 0x1ad4, 0x52da, 0x12b6, 0xe937, 0x92e, 0x1496, 0xb64b, 0xd4a,
    0xda8, 0x95b5, 0x56c, 0x12ae, 0x492f, 0x92e, 0xcc96, 0x1a94, 0x1d4a, 0xada9, 0xb5a, 0x56c, 0x726e, 0x125c,
    0xf92d, 0x192a, 0x1a94, 0xdb4a, 0x16aa, 0xad4, 0x955b, 0x4ba, 0x125a, 0x592b, 0x152a, 0xf695, 0xd94, 0x16aa,
    0xaab5, 0x9b4, 0x14b6, 0x6a57, 0xa56, 0x1152a, 0x1d2a, 0xd54, 0xd5aa, 0x156a, 0x96c, 0x94ae, 0x14ae, 0xa4c,
    0x7d26, 0x1b2a, 0xeb55, 0xad4, 0x12da, 0xa95d, 0x95a, 0x149a, 0x9a4d, 0x1a4a, 0x11aa5, 0x16a8, 0x16d4,
    0xd2da, 0x12b6, 0x936, 0x9497, 0x1496, 0x1564b, 0xd4a, 0xda8, 0xd5b4, 0x156c, 0x12ae, 0xa92f, 0x92e, 0xc96,
    0x6d4a, 0x1d4a, 0x10d65, 0xb58, 0x156c, 0xb26d, 0x125c, 0x192c, 0x9a95, 0x1a94, 0x1b4a, 0x4b55, 0xad4,
    0xf55b, 0x4ba, 0x125a, 0xb92b, 0x152a, 0x1694, 0x96aa, 0x15aa, 0x12ab5, 0x974, 0x14b6, 0xca57, 0xa56, 0x1526,
    0x8e95, 0xd54, 0x15aa, 0x49b5, 0x96c, 0xd4ae, 0x149c, 0x1a4c, 0xbd26, 0x1aa6, 0xb54, 0x6d6a, 0x12da, 0x1695d,
    0x95a, 0x149a, 0xda4b, 0x1a4a, 0x1aa4, 0xbb54, 0x16b4, 0xada, 0x495b, 0x936, 0xf497, 0x1496, 0x154a, 0xb6a5,
    0xda4, 0x15b4, 0x6ab6, 0x126e, 0x1092f, 0x92e, 0xc96, 0xcd4a, 0x1d4a, 0xd64, 0x956c, 0x155c, 0x125c, 0x792e,
    0x192c, 0xfa95, 0x1a94, 0x1b4a, 0xab55, 0xad4, 0x14da, 0x8a5d, 0xa5a, 0x1152b, 0x152a, 0x1694, 0xd6aa,
    0x15aa, 0xab4, 0x94ba, 0x14b6, 0xa56, 0x7527, 0xd26, 0xee53, 0xd54, 0x15aa, 0xa9b5, 0x96c, 0x14ae, 0x8a4e,
    0x1a4c, 0x11d26, 0x1aa4, 0x1b54, 0xcd6a, 0xada, 0x95c, 0x949d, 0x149a, 0x1a2a, 0x5b25, 0x1aa4, 0xfb52,
    0x16b4, 0xaba, 0xa95b, 0x936, 0x1496, 0x9a4b, 0x154a, 0x136a5, 0xda4, 0x15ac
  };
  
  static int solar_1_1[] =
  {
    1887, 0xec04c, 0xec23f, 0xec435, 0xec649, 0xec83e, 0xeca51, 0xecc46, 0xece3a,
    0xed04d, 0xed242, 0xed436, 0xed64a, 0xed83f, 0xeda53, 0xedc48, 0xede3d, 0xee050, 0xee244, 0xee439, 0xee64d,
    0xee842, 0xeea36, 0xeec4a, 0xeee3e, 0xef052, 0xef246, 0xef43a, 0xef64e, 0xef843, 0xefa37, 0xefc4b, 0xefe41,
    0xf0054, 0xf0248, 0xf043c, 0xf0650, 0xf0845, 0xf0a38, 0xf0c4d, 0xf0e42, 0xf1037, 0xf124a, 0xf143e, 0xf1651,
    0xf1846, 0xf1a3a, 0xf1c4e, 0xf1e44, 0xf2038, 0xf224b, 0xf243f, 0xf2653, 0xf2848, 0xf2a3b, 0xf2c4f, 0xf2e45,
    0xf3039, 0xf324d, 0xf3442, 0xf3636, 0xf384a, 0xf3a3d, 0xf3c51, 0xf3e46, 0xf403b, 0xf424e, 0xf4443, 0xf4638,
    0xf484c, 0xf4a3f, 0xf4c52, 0xf4e48, 0xf503c, 0xf524f, 0xf5445, 0xf5639, 0xf584d, 0xf5a42, 0xf5c35, 0xf5e49,
    0xf603e, 0xf6251, 0xf6446, 0xf663b, 0xf684f, 0xf6a43, 0xf6c37, 0xf6e4b, 0xf703f, 0xf7252, 0xf7447, 0xf763c,
    0xf7850, 0xf7a45, 0xf7c39, 0xf7e4d, 0xf8042, 0xf8254, 0xf8449, 0xf863d, 0xf8851, 0xf8a46, 0xf8c3b, 0xf8e4f,
    0xf9044, 0xf9237, 0xf944a, 0xf963f, 0xf9853, 0xf9a47, 0xf9c3c, 0xf9e50, 0xfa045, 0xfa238, 0xfa44c, 0xfa641,
    0xfa836, 0xfaa49, 0xfac3d, 0xfae52, 0xfb047, 0xfb23a, 0xfb44e, 0xfb643, 0xfb837, 0xfba4a, 0xfbc3f, 0xfbe53,
    0xfc048, 0xfc23c, 0xfc450, 0xfc645, 0xfc839, 0xfca4c, 0xfcc41, 0xfce36, 0xfd04a, 0xfd23d, 0xfd451, 0xfd646,
    0xfd83a, 0xfda4d, 0xfdc43, 0xfde37, 0xfe04b, 0xfe23f, 0xfe453, 0xfe648, 0xfe83c, 0xfea4f, 0xfec44, 0xfee38,
    0xff04c, 0xff241, 0xff436, 0xff64a, 0xff83e, 0xffa51, 0xffc46, 0xffe3a, 0x10004e, 0x100242, 0x100437,
    0x10064b, 0x100841, 0x100a53, 0x100c48, 0x100e3c, 0x10104f, 0x101244, 0x101438, 0x10164c, 0x101842, 0x101a35,
    0x101c49, 0x101e3d, 0x102051, 0x102245, 0x10243a, 0x10264e, 0x102843, 0x102a37, 0x102c4b, 0x102e3f, 0x103053,
    0x103247, 0x10343b, 0x10364f, 0x103845, 0x103a38, 0x103c4c, 0x103e42, 0x104036, 0x104249, 0x10443d, 0x104651,
    0x104846, 0x104a3a, 0x104c4e, 0x104e43, 0x105038, 0x10524a, 0x10543e, 0x105652, 0x105847, 0x105a3b, 0x105c4f,
    0x105e45, 0x106039, 0x10624c, 0x106441, 0x106635, 0x106849, 0x106a3d, 0x106c51, 0x106e47, 0x10703c, 0x10724f,
    0x107444, 0x107638, 0x10784c, 0x107a3f, 0x107c53, 0x107e48
  };
  
  static int getfieldfromcalender(lua_State *L, const char *key, int defaultV){
    int isnum;
    int t = lua_getfield(L, -1, key);  /* get field and its type */
    lua_Integer res = lua_tointegerx(L, -1, &isnum);
    if (!isnum) {  /* field is not an integer? */
      if (t != LUA_TNIL)  /* some other value? */
        return luaL_error(L, "field '%s' is not an integer", key);
      else if (defaultV < 0)  /* absent field; no default? */
        return luaL_error(L, "field '%s' missing in date table", key);
      res = defaultV;
    }
    else {
      if (!(-10000 <= res && res <= 10000))
        return luaL_error(L, "field '%s' is out-of-bound", key);
      //res -= delta;
    }
    lua_pop(L, 1);
    return (int)res;
  }
  
  static int getbitint(int data, int length, int shift){
    return (data & (((1 << length) - 1) << shift)) >> shift;
  }
  
  static int solartoint(int y, int m, int d){
    m = (m + 9) % 12;
    y = y - m / 10;
    return 365 * y + y / 4 - y / 100 + y / 400 + (m * 306 + 5) / 10 + (d - 1);
  }
  
  static void setcalenderfield (lua_State *L, const char *key, int value) {
    lua_pushinteger(L, value);
    lua_setfield(L, -2, key);
  }
  
  static void setcalenderboolfield (lua_State *L, const char *key, int value) {
    if (value < 0)  /* undefined? */
      return;  /* does not set field */
    lua_pushboolean(L, value);
    lua_setfield(L, -2, key);
  }
  
  
  static void setcalenderallfields (lua_State *L, int year, int mon, int day, int isLeap) {
    setcalenderfield(L, "day", day);
    setcalenderfield(L, "month", mon);
    setcalenderfield(L, "year", year);
    setcalenderboolfield(L, "isLeap", isLeap);
  }
  
  static int calender_lunartosolar(lua_State *L){
    int lunarYear = getfieldfromcalender(L, "year", 0);
    int lunarMonth = getfieldfromcalender(L, "month", 0);
    int lunarDay = getfieldfromcalender(L, "day", 0);
    int isLeap = getfieldfromcalender(L, "isLeap", 0);
  
    int days = lunar_month_days[lunarYear - lunar_month_days[0]];
    int leap = getbitint(days, 4, 13);
    int offset = 0;
    int loopend = leap;
    if (isLeap != 1){
      if(lunarMonth <= leap || leap == 0){
        loopend = lunarMonth - 1;
      }
      else{
        loopend = lunarMonth;
      }
    }
  
    for (int i = 0; i < loopend; i++) {
      offset += getbitint(days, 1, 12 - i) == 1 ? 30 : 29;
    }
  
    offset += lunarDay;
  
    int solar11 = solar_1_1[lunarYear - solar_1_1[0]];
    int y = getbitint(solar11, 12, 9);
    int m = getbitint(solar11, 4, 5);
    int d = getbitint(solar11, 5, 0);
  
    int intFromSolar = solartoint(y, m, d) + offset - 1;
  
    long yy = (10000LL * intFromSolar + 14780) / 3652425;
    long ddd = intFromSolar - (365 * yy + yy / 4 - yy / 100 + yy / 400);
  
    if (ddd < 0){
      yy --;
      ddd = intFromSolar - (365 * yy + yy / 4 - yy / 100 + yy / 400);
    }
  
    long mi = (100 * ddd + 52) / 3060;
    long mm = (mi + 2) % 12 + 1;
    yy = yy + (mi + 2) / 12;
    long dd = ddd - (mi * 306 + 5) / 10 + 1;
  
    setcalenderallfields(L, (int)yy, (int)mm, (int)dd, 0);
    return 1;
  }
  
  static int calender_solartolunar(lua_State *L){
  	
    int solarYear = getfieldfromcalender(L, "year", 0);
    int solarMonth = getfieldfromcalender(L, "month", 0);
    int solarDay = getfieldfromcalender(L, "day", 0);
  
    //int days = lunar_month_days[lunarYear - lunar_month_days[0]];
    int index = solarYear - solar_1_1[0];
    int data = (solarYear << 9) | (solarMonth << 5) | (solarDay);
    int solar11 = 0;
    if (solar_1_1[index] > data) {
      index--;
    }
  
    solar11 = solar_1_1[index];
    int y = getbitint(solar11, 12, 9);
    int m = getbitint(solar11, 4, 5);
    int d = getbitint(solar11, 5, 0);
  
    long offset = solartoint(solarYear, solarMonth, solarDay) - solartoint(y, m, d);
  
    int days = lunar_month_days[index];
    int leap = getbitint(days, 4, 13);
  
    int lunarY = index + solar_1_1[0];
    int lunarM = 1;
    int lunarD;
    offset += 1;
  
    for (int i = 0; i < 13; i++) {
      int dm = getbitint(days, 1, 12 - i) == 1 ? 30 : 29;
      if (offset > dm) {
        lunarM++;
        offset -= dm;
      }
      else {
        break;
      }
    }
  
    lunarD = (int) (offset);
    int lunarYear = lunarY;
    int lunarMonth = lunarM;
    int isleap = 0;
  
    if (leap != 0 && lunarM > leap) {
      lunarMonth = lunarM - 1;
      if (lunarM == leap + 1) {
        isleap = 1;
      }
    }
  
    int lunarDay = lunarD;
  
    lua_createtable(L, 0, 4);  /* 4 = number of fields */
    setcalenderallfields(L, lunarYear, lunarMonth, lunarDay, isleap);
  
    return 1;
  
  }
  
  static const luaL_Reg syslib[] = {
    {"lunartosolar",     calender_lunartosolar},
    {"solartolunar",     calender_solartolunar},
    {NULL, NULL}
  };
  
  /* }====================================================== */
  
  
  
  LUAMOD_API int luaopen_calender (lua_State *L) {
    luaL_newlib(L, syslib);
    return 1;
  }
  
  
  