src/lj_lib.c

   1 /*
   2 ** Library function support.
   3 ** Copyright (C) 2005-2009 Mike Pall. See Copyright Notice in luajit.h
   4 */
   5
   6 #define lj_lib_c
   7 #define LUA_CORE
   8
   9 #include "lauxlib.h"
  10
  11 #include "lj_obj.h"
  12 #include "lj_gc.h"
  13 #include "lj_err.h"
  14 #include "lj_str.h"
  15 #include "lj_tab.h"
  16 #include "lj_func.h"
  17 #include "lj_vm.h"
  18 #include "lj_lib.h"
  19
  20 /* -- Library initialization ---------------------------------------------- */
  21
  22 static GCtab *lib_create_table(lua_State *L, const char *libname, int hsize)
  23 {
  24   if (libname) {
  25     luaL_findtable(L, LUA_REGISTRYINDEX, "_LOADED", 16);
  26     lua_getfield(L, -1, libname);
  27     if (!tvistab(L->top-1)) {
  28       L->top--;
  29       if (luaL_findtable(L, LUA_GLOBALSINDEX, libname, hsize) != NULL)
  30         lj_err_callerv(L, LJ_ERR_BADMODN, libname);
  31       settabV(L, L->top, tabV(L->top-1));
  32       L->top++;
  33       lua_setfield(L, -3, libname);  /* _LOADED[libname] = new table */
  34     }
  35     L->top--;
  36     settabV(L, L->top-1, tabV(L->top));
  37   } else {
  38     lua_createtable(L, 0, hsize);
  39   }
  40   return tabV(L->top-1);
  41 }
  42
  43 void lj_lib_register(lua_State *L, const char *libname,
  44                      const uint8_t *p, const lua_CFunction *cf)
  45 {
  46   GCtab *env = tabref(L->env);
  47   GCfunc *ofn = NULL;
  48   int ffid = *p++;
  49   GCtab *tab = lib_create_table(L, libname, *p++);
  50   ptrdiff_t tpos = L->top - L->base;
  51
  52   /* Avoid barriers further down. */
  53   if (isblack(obj2gco(tab))) lj_gc_barrierback(G(L), tab);
  54   tab->nomm = 0;
  55
  56   for (;;) {
  57     uint32_t tag = *p++;
  58     MSize len = tag & LIBINIT_LENMASK;
  59     tag &= LIBINIT_TAGMASK;
  60     if (tag != LIBINIT_STRING) {
  61       const char *name;
  62       MSize nuv = (MSize)(L->top - L->base - tpos);
  63       GCfunc *fn = lj_func_newC(L, nuv, env);
  64       if (nuv) {
  65         L->top = L->base + tpos;
  66         memcpy(fn->c.upvalue, L->top, sizeof(TValue)*nuv);
  67       }
  68       fn->c.ffid = (uint8_t)(ffid++);
  69       name = (const char *)p;
  70       p += len;
  71       if (tag != LIBINIT_CF) {
  72         fn->c.gate = makeasmfunc(p[0] + (p[1] << 8));
  73         p += 2;
  74       }
  75       if (tag == LIBINIT_ASM_)
  76         fn->c.f = ofn->c.f;  /* Copy handler from previous function. */
  77       else
  78         fn->c.f = *cf++;  /* Get cf or handler from C function table. */
  79       if (len) {
  80         /* NOBARRIER: See above for common barrier. */
  81         setfuncV(L, lj_tab_setstr(L, tab, lj_str_new(L, name, len)), fn);
  82       }
  83       ofn = fn;
  84     } else {
  85       switch (tag | len) {
  86       case LIBINIT_SET:
  87         L->top -= 2;
  88         if (tvisstr(L->top+1) && strV(L->top+1)->len == 0)
  89           env = tabV(L->top);
  90         else  /* NOBARRIER: See above for common barrier. */
  91           copyTV(L, lj_tab_set(L, tab, L->top+1), L->top);
  92         break;
  93       case LIBINIT_NUMBER:
  94         memcpy(&L->top->n, p, sizeof(double));
  95         L->top++;
  96         p += sizeof(double);
  97         break;
  98       case LIBINIT_COPY:
  99         copyTV(L, L->top, L->top - *p++);
 100         L->top++;
 101         break;
 102       case LIBINIT_LASTCL:
 103         setfuncV(L, L->top++, ofn);
 104         break;
 105       case LIBINIT_FFID:
 106         ffid++;
 107         break;
 108       case LIBINIT_END:
 109         return;
 110       default:
 111         setstrV(L, L->top++, lj_str_new(L, (const char *)p, len));
 112         p += len;
 113         break;
 114       }
 115     }
 116   }
 117 }
 118
 119 /* -- Type checks --------------------------------------------------------- */
 120
 121 TValue *lj_lib_checkany(lua_State *L, int narg)
 122 {
 123   TValue *o = L->base + narg-1;
 124   if (o >= L->top)
 125     lj_err_arg(L, narg, LJ_ERR_NOVAL);
 126   return o;
 127 }
 128
 129 GCstr *lj_lib_checkstr(lua_State *L, int narg)
 130 {
 131   TValue *o = L->base + narg-1;
 132   if (o < L->top) {
 133     if (LJ_LIKELY(tvisstr(o))) {
 134       return strV(o);
 135     } else if (tvisnum(o)) {
 136       GCstr *s = lj_str_fromnum(L, &o->n);
 137       setstrV(L, o, s);
 138       return s;
 139     }
 140   }
 141   lj_err_argt(L, narg, LUA_TSTRING);
 142   return NULL;  /* unreachable */
 143 }
 144
 145 GCstr *lj_lib_optstr(lua_State *L, int narg)
 146 {
 147   TValue *o = L->base + narg-1;
 148   return (o < L->top && !tvisnil(o)) ? lj_lib_checkstr(L, narg) : NULL;
 149 }
 150
 151 lua_Number lj_lib_checknum(lua_State *L, int narg)
 152 {
 153   TValue *o = L->base + narg-1;
 154   if (!(o < L->top &&
 155         (tvisnum(o) || (tvisstr(o) && lj_str_tonum(strV(o), o)))))
 156     lj_err_argt(L, narg, LUA_TNUMBER);
 157   return numV(o);
 158 }
 159
 160 int32_t lj_lib_checkint(lua_State *L, int narg)
 161 {
 162   return lj_num2int(lj_lib_checknum(L, narg));
 163 }
 164
 165 int32_t lj_lib_optint(lua_State *L, int narg, int32_t def)
 166 {
 167   TValue *o = L->base + narg-1;
 168   return (o < L->top && !tvisnil(o)) ? lj_lib_checkint(L, narg) : def;
 169 }
 170
 171 GCfunc *lj_lib_checkfunc(lua_State *L, int narg)
 172 {
 173   TValue *o = L->base + narg-1;
 174   if (!(o < L->top && tvisfunc(o)))
 175     lj_err_argt(L, narg, LUA_TFUNCTION);
 176   return funcV(o);
 177 }
 178
 179 GCtab *lj_lib_checktab(lua_State *L, int narg)
 180 {
 181   TValue *o = L->base + narg-1;
 182   if (!(o < L->top && tvistab(o)))
 183     lj_err_argt(L, narg, LUA_TTABLE);
 184   return tabV(o);
 185 }
 186
 187 GCtab *lj_lib_checktabornil(lua_State *L, int narg)
 188 {
 189   TValue *o = L->base + narg-1;
 190   if (o < L->top) {
 191     if (tvistab(o))
 192       return tabV(o);
 193     else if (tvisnil(o))
 194       return NULL;
 195   }
 196   lj_err_arg(L, narg, LJ_ERR_NOTABN);
 197   return NULL;  /* unreachable */
 198 }
 199
 200 int lj_lib_checkopt(lua_State *L, int narg, int def, const char *lst)
 201 {
 202   GCstr *s = def >= 0 ? lj_lib_optstr(L, narg) : lj_lib_checkstr(L, narg);
 203   if (s) {
 204     const char *opt = strdata(s);
 205     MSize len = s->len;
 206     int i;
 207     for (i = 0; *(const uint8_t *)lst; i++) {
 208       if (*(const uint8_t *)lst == len && memcmp(opt, lst+1, len) == 0)
 209         return i;
 210       lst += 1+*(const uint8_t *)lst;
 211     }
 212     lj_err_argv(L, narg, LJ_ERR_INVOPTM, opt);
 213   }
 214   return def;
 215 }
 216