mylib.c
/// A sample C extension. // Demonstrates using ldoc's C/C++ support. Can either use /// or /*** */ etc. // @module mylib #include <string.h> #include <math.h> // includes for Lua #include <lua.h> #include <lauxlib.h> #include <lualib.h> /*** Create a table with given array and hash slots. @function createtable @param narr initial array slots, default 0 @param nrec initial hash slots, default 0 */ static int l_createtable (lua_State *L) { int narr = luaL_optint(L,1,0); int nrec = luaL_optint(L,2,0); lua_createtable(L,narr,nrec); return 1; } /*** Solve a quadratic equation. @function solve @tparam num a coefficient of x^2 @tparam num b coefficient of x @tparam num c constant @treturn num first root @treturn num second root */ static int l_solve (lua_State *L) { double a = lua_tonumber(L,1); // coeff of x*x double b = lua_tonumber(L,2); // coef of x double c = lua_tonumber(L,3); // constant double abc = b*b - 4*a*c; if (abc < 0.0) { lua_pushnil(L); lua_pushstring(L,"imaginary roots!"); return 2; } else { abc = sqrt(abc); a = 2*a; lua_pushnumber(L,(-b + abc)/a); lua_pushnumber(L,(+b - abc)/a); return 2; } } static const luaL_reg mylib[] = { {"createtable",l_createtable}, {"solve",l_solve}, {NULL,NULL} }; int luaopen_mylib(lua_State *L) { luaL_register (L, "mylib", mylib); return 1; }