| Elliott Hughes | d35df49 | 2017-02-15 15:19:05 -0800 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2016 Dmitry V. Levin <ldv@altlinux.org> |
| 3 | * All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
| 13 | * 3. The name of the author may not be used to endorse or promote products |
| 14 | * derived from this software without specific prior written permission. |
| 15 | * |
| 16 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 17 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 18 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 19 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 20 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 21 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 22 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 23 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 24 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 25 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 26 | */ |
| 27 | |
| 28 | #include "tests.h" |
| 29 | #include <limits.h> |
| 30 | #include <unistd.h> |
| 31 | #include <sys/resource.h> |
| 32 | |
| 33 | static void |
| 34 | move_fd(int *from, int *to) |
| 35 | { |
| 36 | for (; *to > *from; --*to) { |
| 37 | if (dup2(*from, *to) != *to) |
| 38 | continue; |
| 39 | close(*from); |
| 40 | *from = *to; |
| 41 | break; |
| 42 | } |
| 43 | } |
| 44 | |
| 45 | void |
| 46 | pipe_maxfd(int pipefd[2]) |
| 47 | { |
| 48 | struct rlimit rlim; |
| 49 | if (getrlimit(RLIMIT_NOFILE, &rlim)) |
| 50 | perror_msg_and_fail("getrlimit"); |
| 51 | if (rlim.rlim_cur < rlim.rlim_max) { |
| 52 | struct rlimit rlim_new; |
| 53 | rlim_new.rlim_cur = rlim_new.rlim_max = rlim.rlim_max; |
| 54 | if (!setrlimit(RLIMIT_NOFILE, &rlim_new)) |
| 55 | rlim.rlim_cur = rlim.rlim_max; |
| 56 | } |
| 57 | |
| 58 | if (pipe(pipefd)) |
| 59 | perror_msg_and_fail("pipe"); |
| 60 | |
| 61 | int max_fd = (rlim.rlim_cur > 0 && rlim.rlim_cur < INT_MAX) |
| 62 | ? rlim.rlim_cur - 1 : INT_MAX; |
| 63 | |
| 64 | move_fd(&pipefd[1], &max_fd); |
| 65 | --max_fd; |
| 66 | move_fd(&pipefd[0], &max_fd); |
| 67 | } |