etc/min.c

   1 /*
   2 * min.c -- a minimal Lua interpreter
   3 * loads stdin only with minimal error handling.
   4 * no interaction, and no standard library, only a "print" function.
   5 */
   6
   7 #include <stdio.h>
   8 #include "lua.h"
   9
  10 static int print(lua_State *L)
  11 {
  12  int n=lua_gettop(L);
  13  int i;
  14  for (i=1; i<=n; i++)
  15  {
  16   if (i>1) printf("\t");
  17   if (lua_isstring(L,i))
  18    printf("%s",lua_tostring(L,i));
  19   else if (lua_isnil(L,i))
  20    printf("%s","nil");
  21   else if (lua_isboolean(L,i))
  22    printf("%s",lua_toboolean(L,i) ? "true" : "false");
  23   else
  24    printf("%s:%p",lua_typename(L,lua_type(L,i)),lua_topointer(L,i));
  25  }
  26  printf("\n");
  27  return 0;
  28 }
  29
  30 static const char *getF(lua_State *L, void *ud, size_t *size)
  31 {
  32  FILE *f=(FILE *)ud;
  33  static char buff[512];
  34  if (feof(f)) return NULL;
  35  *size=fread(buff,1,sizeof(buff),f);
  36  return (*size>0) ? buff : NULL;
  37 }
  38
  39 int main(void)
  40 {
  41  lua_State *L=lua_open();
  42  lua_register(L,"print",print);
  43  if (lua_load(L,getF,stdin,"=stdin") || lua_pcall(L,0,0,0))
  44   fprintf(stderr,"%s\n",lua_tostring(L,-1));
  45  return 0;
  46 }