File: rand_util_fuchsia.cc

package info (click to toggle)
qtwebengine-opensource-src 5.11.3%2Bdfsg-2%2Bdeb10u1
  • links: PTS, VCS
  • area: main
  • in suites: buster
  • size: 1,551,988 kB
  • sloc: cpp: 10,064,061; ansic: 3,832,841; asm: 590,489; python: 455,759; xml: 261,729; sh: 90,157; objc: 77,089; perl: 71,296; makefile: 27,041; cs: 23,492; yacc: 14,360; tcl: 12,756; php: 4,714; lex: 4,028; pascal: 3,741; ml: 3,543; ruby: 1,497; lisp: 1,490; awk: 183; csh: 117; sed: 54
file content (33 lines) | stat: -rw-r--r-- 881 bytes parent folder | download 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
 
// Copyright 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/rand_util.h"

#include <zircon/syscalls.h>

#include <algorithm>

#include "base/logging.h"

namespace base {

void RandBytes(void* output, size_t output_length) {
  size_t remaining = output_length;
  unsigned char* cur = reinterpret_cast<unsigned char*>(output);
  while (remaining > 0) {
    // The syscall has a maximum number of bytes that can be read at once.
    size_t read_len =
        std::min(remaining, static_cast<size_t>(ZX_CPRNG_DRAW_MAX_LEN));

    size_t actual;
    zx_status_t status = zx_cprng_draw(cur, read_len, &actual);
    CHECK(status == ZX_OK && read_len == actual);

    CHECK(remaining >= actual);
    remaining -= actual;
    cur += actual;
  }
}

}  // namespace base