static IOFileUD *io_file_open(lua_State *L, const char *mode)
{
const char *fname = strdata(lj_lib_checkstr(L, 1));
IOFileUD *iof = io_file_new(L);
iof->fp = fopen(fname, mode);
if (iof->fp == NULL)
luaL_argerror(L, 1, lj_str_pushf(L, "%s: %s", fname, strerror(errno)));
return iof;
}
/* Helper for ISTYPE and ISNUM. Implicit coercion or error. */
void lj_meta_istype(lua_State *L, BCReg ra, BCReg tp)
{
L->top = curr_topL(L);
ra++; tp--;
lua_assert(LJ_DUALNUM || tp != ~LJ_TNUMX); /* ISTYPE -> ISNUM broken. */
if (LJ_DUALNUM && tp == ~LJ_TNUMX) lj_lib_checkint(L, ra);
else if (tp == ~LJ_TNUMX+1) lj_lib_checknum(L, ra);
else if (tp == ~LJ_TSTR) lj_lib_checkstr(L, ra);
else lj_err_argtype(L, ra, lj_obj_itypename[tp]);
}
int lj_lib_checkopt(lua_State *L, int narg, int def, const char *lst)
{
GCstr *s = def >= 0 ? lj_lib_optstr(L, narg) : lj_lib_checkstr(L, narg);
if (s) {
const char *opt = strdata(s);
MSize len = s->len;
int i;
for (i = 0; *(const uint8_t *)lst; i++) {
if (*(const uint8_t *)lst == len && memcmp(opt, lst+1, len) == 0)
return i;
lst += 1+*(const uint8_t *)lst;
}
lj_err_argv(L, narg, LJ_ERR_INVOPTM, opt);
}
return def;
}
#include "lj_lib.h"
/* ------------------------------------------------------------------------ */
#define LJLIB_MODULE_string
LJLIB_LUA(string_len) /*
function(s)
CHECK_str(s)
return #s
end
*/
LJLIB_ASM(string_byte) LJLIB_REC(string_range 0)
{
GCstr *s = lj_lib_checkstr(L, 1);
int32_t len = (int32_t)s->len;
int32_t start = lj_lib_optint(L, 2, 1);
int32_t stop = lj_lib_optint(L, 3, start);
int32_t n, i;
const unsigned char *p;
if (stop < 0) stop += len+1;
if (start < 0) start += len+1;
if (start <= 0) start = 1;
if (stop > len) stop = len;
if (start > stop) return FFH_RES(0); /* Empty interval: return no results. */
start--;
n = stop - start;
if ((uint32_t)n > LUAI_MAXCSTACK)
lj_err_caller(L, LJ_ERR_STRSLC);
lj_state_checkstack(L, (MSize)n);
GCstr *lj_lib_optstr(lua_State *L, int narg)
{
TValue *o = L->base + narg-1;
return (o < L->top && !tvisnil(o)) ? lj_lib_checkstr(L, narg) : NULL;
}
