JL_DLLEXPORT uint64_t jl_ios_get_nbyte_int(ios_t *s, const size_t n)
{
assert(n <= 8);
size_t space, ret;
do {
space = (size_t)(s->size - s->bpos);
ret = ios_readprep(s, n);
if (space == ret && ret < n)
jl_eof_error();
} while(ret < n);
uint64_t x = 0;
uint8_t *buf = (uint8_t*)&s->buf[s->bpos];
if (n == 8) {
// expecting loop unrolling optimization
for (size_t i = 0; i < 8; i++)
x |= (uint64_t)buf[i] << (i << 3);
}
else if (n >= 4) {
// expecting loop unrolling optimization
for (size_t i = 0; i < 4; i++)
x |= (uint64_t)buf[i] << (i << 3);
for (size_t i = 4; i < n; i++)
x |= (uint64_t)buf[i] << (i << 3);
}
else {
for (size_t i = 0; i < n; i++)
x |= (uint64_t)buf[i] << (i << 3);
}
s->bpos += n;
return x;
}
JL_DLLEXPORT int jl_fs_read_byte(int handle)
{
uv_fs_t req;
char c;
uv_buf_t buf[1];
buf[0].base = &c;
buf[0].len = 1;
int ret = uv_fs_read(jl_io_loop, &req, handle, buf, 1, -1, NULL);
uv_fs_req_cleanup(&req);
switch (ret) {
case -1: return ret;
case 0: jl_eof_error();
case 1: return (int)c;
default:
assert(0 && "jl_fs_read_byte: Invalid return value from uv_fs_read");
return -1;
}
}
