/*------------------------------------------------------------
* Vport Getb
*/
static int vport_getb(ScmPort *p)
{
vport *data = (vport*)p->src.vt.data;
SCM_ASSERT(data != NULL);
if (SCM_FALSEP(data->getb_proc)) {
/* If the port doesn't have get-byte method, use get-char
if possible. */
ScmObj ch;
ScmChar c;
char buf[SCM_CHAR_MAX_BYTES];
int nb, i;
if (SCM_FALSEP(data->getc_proc)) return EOF;
ch = Scm_ApplyRec(data->getc_proc, SCM_NIL);
if (!SCM_CHARP(ch)) return EOF;
c = SCM_CHAR_VALUE(ch);
nb = SCM_CHAR_NBYTES(c);
SCM_CHAR_PUT(buf, c);
for (i=1; i<nb; i++) {
/* pushback for later use. this isn't very efficient;
if efficiency becomes a problem, we need another API
to pushback multiple bytes. */
Scm_UngetbUnsafe(buf[i], p);
}
return buf[0];
} else {
ScmObj b = Scm_ApplyRec(data->getb_proc, SCM_NIL);
if (!SCM_INTP(b)) return EOF;
return (SCM_INT_VALUE(b) & 0xff);
}
}
void Scm_UngetbUnsafe(int b, ScmPort *p)
#endif
{
VMDECL;
SHORTCUT(p, Scm_UngetbUnsafe(b, p); return);
LOCK(p);
if (p->ungotten != SCM_CHAR_INVALID
|| p->scrcnt >= SCM_CHAR_MAX_BYTES) {
Scm_PortError(p, SCM_PORT_ERROR_INPUT,
"pushback buffer overflow on port %S", p);
}
p->scratch[p->scrcnt++] = b;
UNLOCK(p);
}
/* NB: this routine reads bytes, not chars. It allows to readline
from a port in unknown character encoding (e.g. reading the first
line of xml doc to find out charset parameter). */
ScmObj readline_body(ScmPort *p)
{
ScmDString ds;
Scm_DStringInit(&ds);
int b1 = Scm_GetbUnsafe(p);
if (b1 == EOF) return SCM_EOF;
for (;;) {
if (b1 == EOF) return Scm_DStringGet(&ds, 0);
if (b1 == '\n') break;
if (b1 == '\r') {
int b2 = Scm_GetbUnsafe(p);
if (b2 == EOF || b2 == '\n') break;
Scm_UngetbUnsafe(b2, p);
break;
}
SCM_DSTRING_PUTB(&ds, b1);
b1 = Scm_GetbUnsafe(p);
}
p->line++;
return Scm_DStringGet(&ds, 0);
}
