File: invalidate-before-swap-iterators.cpp

package info (click to toggle)
chromium 139.0.7258.127-1
  • links: PTS, VCS
  • area: main
  • in suites:
  • size: 6,122,068 kB
  • sloc: cpp: 35,100,771; ansic: 7,163,530; javascript: 4,103,002; python: 1,436,920; asm: 946,517; xml: 746,709; pascal: 187,653; perl: 88,691; sh: 88,436; objc: 79,953; sql: 51,488; cs: 44,583; fortran: 24,137; makefile: 22,147; tcl: 15,277; php: 13,980; yacc: 8,984; ruby: 7,485; awk: 3,720; lisp: 3,096; lex: 1,327; ada: 727; jsp: 228; sed: 36
file content (26 lines) | stat: -rw-r--r-- 626 bytes parent folder | download | duplicates (6)
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
// Copyright 2024 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <algorithm>
#include <vector>

void InvalidateBeforeSwapIterators(std::vector<int> v1, std::vector<int> v2) {
  auto it1 = std::begin(v1);
  auto it2 = std::begin(v2);
  if (it1 == std::end(v1) || it2 == std::end(v2)) {
    return;
  }
  // Both iterators are valid before the swap.
  *it1 = 0;
  *it2 = 0;

  // This invalidates `it1`.
  v1.clear();
  *it1 = 0;

  std::swap(it1, it2);

  // After the swap, `it2` is not valid and `it1` is valid.
  *it1 = 0;
  *it2 = 0;
}