98 lines
2.2 KiB
C
98 lines
2.2 KiB
C
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/* This testcase is part of GDB, the GNU debugger.
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Copyright 2016 Free Software Foundation, Inc.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <assert.h>
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int fds[2] = { -1, -1 };
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static void
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grandparent_done (void)
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{
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}
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/* The exp file overrides this in order to test both fork and
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vfork. */
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#ifndef FORK
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#define FORK fork
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#endif
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int
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main (void)
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{
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int pid;
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int nbytes;
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const char string[] = "Hello, world!\n";
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char readbuffer[80];
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/* Don't run forever. */
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alarm (300);
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/* Create a pipe. The write side will be inherited all the way to
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the grandchild. The grandparent will read this, expecting to see
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EOF (meaning the grandchild closed the pipe). */
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pipe (fds);
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pid = FORK ();
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if (pid < 0)
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{
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perror ("fork");
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exit (1);
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}
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else if (pid == 0)
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{
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/* Close input side of pipe. */
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close (fds[0]);
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pid = FORK ();
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if (pid == 0)
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{
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printf ("I'm the grandchild!\n");
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/* Don't explicitly close the pipe. If GDB fails to kill
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this process, then the grandparent will hang in the pipe
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read below. */
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#if 0
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close (fds[1]);
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#endif
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while (1)
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sleep (1);
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}
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else
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{
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close (fds[1]);
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printf ("I'm the proud parent of child #%d!\n", pid);
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wait (NULL);
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}
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}
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else if (pid > 0)
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{
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close (fds[1]);
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printf ("I'm the proud parent of child #%d!\n", pid);
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nbytes = read (fds[0], readbuffer, sizeof (readbuffer));
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assert (nbytes == 0);
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printf ("read returned nbytes=%d\n", nbytes);
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wait (NULL);
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grandparent_done ();
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}
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return 0;
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}
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