v/vlib/crypto/rand/rand_solaris.c.v

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1.1 KiB
V

// Copyright (c) 2019-2021 Alexander Medvednikov. All rights reserved.
// Use of this source code is governed by an MIT license
// that can be found in the LICENSE file.
module rand
#include <sys/random.h>
fn C.getrandom(p byteptr, n size_t, flags u32) int
const (
read_batch_size = 256
)
pub fn read(bytes_needed int) ?[]byte {
mut buffer := &byte(0)
unsafe {
buffer = malloc(bytes_needed)
}
mut bstart := buffer
mut bytes_read := 0
mut remaining_bytes := bytes_needed
// getrandom syscall wont block if requesting <= 256 bytes
for bytes_read < bytes_needed {
batch_size := if remaining_bytes > read_batch_size { read_batch_size } else { remaining_bytes }
unsafe {
bstart = buffer + bytes_read
}
rbytes := getrandom(batch_size, bstart)
if rbytes == -1 {
free(buffer)
return read_error
}
bytes_read += rbytes
}
return c_array_to_bytes_tmp(bytes_needed, buffer)
}
fn v_getrandom(bytes_needed int, buffer voidptr) int {
if bytes_needed > read_batch_size {
panic('getrandom() dont request more than $read_batch_size bytes at once.')
}
return C.getrandom(buffer, bytes_needed, 0)
}