| 1 | /* This testcase is part of GDB, the GNU debugger. |
| 2 | |
| 3 | Copyright 2017-2021 Free Software Foundation, Inc. |
| 4 | |
| 5 | This program is free software; you can redistribute it and/or modify |
| 6 | it under the terms of the GNU General Public License as published by |
| 7 | the Free Software Foundation; either version 3 of the License, or |
| 8 | (at your option) any later version. |
| 9 | |
| 10 | This program is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | GNU General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU General Public License |
| 16 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 17 | |
| 18 | #include <unistd.h> |
| 19 | #include <stdlib.h> |
| 20 | #include <assert.h> |
| 21 | |
| 22 | static void |
| 23 | daemon_main (void) |
| 24 | { |
| 25 | } |
| 26 | |
| 27 | int |
| 28 | main () |
| 29 | { |
| 30 | pid_t child; |
| 31 | |
| 32 | alarm (60); |
| 33 | |
| 34 | /* Normally we're a progress group leader at this point, so can't |
| 35 | create a session. Fork so the child can create a new |
| 36 | session. */ |
| 37 | child = fork (); |
| 38 | if (child == -1) |
| 39 | return 1; |
| 40 | else if (child != 0) |
| 41 | return 0; |
| 42 | else |
| 43 | { |
| 44 | /* In child. Switch to a new session. */ |
| 45 | pid_t session = setsid (); |
| 46 | if (session == -1) |
| 47 | return 1; |
| 48 | |
| 49 | /* Fork again, so that the grand child (what we want to debug) |
| 50 | can't accidentally acquire a controlling terminal, because |
| 51 | it's not a session leader. We're not opening any file here, |
| 52 | but this is representative of what daemons do. */ |
| 53 | child = fork (); |
| 54 | if (child == -1) |
| 55 | return 1; |
| 56 | else if (child != 0) |
| 57 | return 0; |
| 58 | |
| 59 | /* In grandchild. */ |
| 60 | daemon_main (); |
| 61 | |
| 62 | while (1) |
| 63 | sleep (1); |
| 64 | } |
| 65 | |
| 66 | return 0; |
| 67 | } |