static void io_file_readall(lua_State *L, FILE *fp)
{
MSize m, n;
for (m = LUAL_BUFFERSIZE, n = 0; ; m += m) {
char *buf = lj_buf_tmp(L, m);
n += (MSize)fread(buf+n, 1, m-n, fp);
if (n != m) {
setstrV(L, L->top++, lj_str_new(L, buf, (size_t)n));
lj_gc_check(L);
return;
}
}
}
static int io_file_readlen(lua_State *L, FILE *fp, MSize m)
{
if (m) {
char *buf = lj_buf_tmp(L, m);
MSize n = (MSize)fread(buf, 1, m, fp);
setstrV(L, L->top++, lj_str_new(L, buf, (size_t)n));
lj_gc_check(L);
return (n > 0 || m == 0);
} else {
int c = getc(fp);
ungetc(c, fp);
setstrV(L, L->top++, &G(L)->strempty);
return (c != EOF);
}
}
static int io_file_readline(lua_State *L, FILE *fp, MSize chop)
{
MSize m = LUAL_BUFFERSIZE, n = 0, ok = 0;
char *buf;
for (;;) {
buf = lj_buf_tmp(L, m);
if (fgets(buf+n, m-n, fp) == NULL) break;
n += (MSize)strlen(buf+n);
ok |= n;
if (n && buf[n-1] == '\n') { n -= chop; break; }
if (n >= m - 64) m += m;
}
setstrV(L, L->top++, lj_str_new(L, buf, (size_t)n));
lj_gc_check(L);
return (int)ok;
}
/* Helper for CAT. Coercion, iterative concat, __concat metamethod. */
TValue *lj_meta_cat(lua_State *L, TValue *top, int left)
{
int fromc = 0;
if (left < 0) { left = -left; fromc = 1; }
do {
if (!(tvisstr(top) || tvisnumber(top)) ||
!(tvisstr(top-1) || tvisnumber(top-1))) {
cTValue *mo = lj_meta_lookup(L, top-1, MM_concat);
if (tvisnil(mo)) {
mo = lj_meta_lookup(L, top, MM_concat);
if (tvisnil(mo)) {
if (tvisstr(top-1) || tvisnumber(top-1)) top++;
lj_err_optype(L, top-1, LJ_ERR_OPCAT);
return NULL; /* unreachable */
}
}
/* One of the top two elements is not a string, call __cat metamethod:
**
** before: [...][CAT stack .........................]
** top-1 top top+1 top+2
** pick two: [...][CAT stack ...] [o1] [o2]
** setup mm: [...][CAT stack ...] [cont|?] [mo|tmtype] [o1] [o2]
** in asm: [...][CAT stack ...] [cont|PC] [mo|delta] [o1] [o2]
** ^-- func base ^-- mm base
** after mm: [...][CAT stack ...] <--push-- [result]
** next step: [...][CAT stack .............]
*/
copyTV(L, top+2*LJ_FR2+2, top); /* Carefully ordered stack copies! */
copyTV(L, top+2*LJ_FR2+1, top-1);
copyTV(L, top+LJ_FR2, mo);
setcont(top-1, lj_cont_cat);
if (LJ_FR2) { setnilV(top); setnilV(top+2); top += 2; }
return top+1; /* Trigger metamethod call. */
} else {
/* Pick as many strings as possible from the top and concatenate them:
**
** before: [...][CAT stack ...........................]
** pick str: [...][CAT stack ...] [...... strings ......]
** concat: [...][CAT stack ...] [result]
** next step: [...][CAT stack ............]
*/
TValue *e, *o = top;
uint64_t tlen = tvisstr(o) ? strV(o)->len : STRFMT_MAXBUF_NUM;
char *p, *buf;
do {
o--; tlen += tvisstr(o) ? strV(o)->len : STRFMT_MAXBUF_NUM;
} while (--left > 0 && (tvisstr(o-1) || tvisnumber(o-1)));
if (tlen >= LJ_MAX_STR) lj_err_msg(L, LJ_ERR_STROV);
p = buf = lj_buf_tmp(L, (MSize)tlen);
for (e = top, top = o; o <= e; o++) {
if (tvisstr(o)) {
GCstr *s = strV(o);
MSize len = s->len;
p = lj_buf_wmem(p, strdata(s), len);
} else if (tvisint(o)) {
p = lj_strfmt_wint(p, intV(o));
} else {
lua_assert(tvisnum(o));
p = lj_strfmt_wnum(p, o);
}
}
setstrV(L, top, lj_str_new(L, buf, (size_t)(p-buf)));
}
} while (left >= 1);
if (LJ_UNLIKELY(G(L)->gc.total >= G(L)->gc.threshold)) {
if (!fromc) L->top = curr_topL(L);
lj_gc_step(L);
}
return NULL;
}
