SEXP dybuf_collect(SEXP s) {
dybuf_info_t *d = (dybuf_info_t*) RAW(VECTOR_ELT(s, 1));
unsigned long total = 0;
char *dst;
SEXP head = VECTOR_ELT(s, 0), res;
if (d->con) {
long wr;
/* FIXME: should we try partial sends as well ? */
if ((wr = R_WriteConnection(d->con, d->data, d->pos)) != d->pos)
Rf_error("write failed, expected %lu, got %ld", d->pos, wr);
d->pos = 0;
return R_NilValue;
}
while (d->tail != head) {
total += LENGTH(CAR(head));
head = CDR(head);
}
total += d->pos;
dst = (char*) RAW(res = PROTECT(allocVector(RAWSXP, total)));
head = VECTOR_ELT(s, 0);
while (d->tail != head) {
int l = LENGTH(CAR(head));
memcpy(dst, RAW(CAR(head)), l);
dst += l;
head = CDR(head);
}
if (d->pos) memcpy(dst, RAW(CAR(head)), d->pos);
UNPROTECT(1);
return res;
}
std::streamsize connection_sink::write(const char* s, std::streamsize n) {
size_t write_size;
if ((write_size = R_WriteConnection(con_, (void*)s, n)) !=
static_cast<size_t>(n)) {
Rcpp::stop("write failed, expected %l, got %l", n, write_size);
}
return write_size;
}
void dybuf_add(SEXP s, const char *data, unsigned long len) {
dybuf_info_t *d = (dybuf_info_t*) RAW(VECTOR_ELT(s, 1));
unsigned long n = (d->pos + len > d->size) ? (d->size - d->pos) : len;
if (!len) return;
/* printf("[%lu/%lu] %lu\n", d->pos, d->size, len); */
if (n) {
memcpy(d->data + d->pos, data, n);
d->pos += n;
if (len == n) return;
data += n;
len -= n;
}
/* printf("[%lu/%lu] filled, need %lu more", d->pos, d->size, len); */
/* if the output is connection-based, flush */
if (d->con) {
long wr;
/* FIXME: should we try partial sends as well ? */
if ((wr = R_WriteConnection(d->con, d->data, d->pos)) != d->pos)
Rf_error("write failed, expected %lu, got %ld", d->pos, wr);
d->pos = 0;
/* if the extra content is substantially big, don't even
bother storing it and send right away */
if (len > (d->size / 2)) {
/* FIXME: (actually FIX R): WriteConnection should be using const void* */
if ((wr = R_WriteConnection(d->con, (void*) data, len)) != len)
Rf_error("write failed, expected %lu, got %ld", len, wr);
} else { /* otherwise copy into the buffer */
memcpy(d->data, data, len);
d->pos = len;
}
} else { /* need more buffers */
SEXP nb;
while (len > d->size) d->size *= 2;
/* printf(", creating %lu more\n", d->size); */
d->tail = SETCDR(d->tail, list1(nb = allocVector(RAWSXP, d->size)));
memcpy(d->data = (char*) RAW(nb), data, len);
d->pos = len;
}
}
