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/* Copyright 1992-2020 Free Software Foundation, Inc.
This file is part of GDB.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
/* Simple little program that just generates a core dump from inside some
nested function calls. */
#include <stdio.h>
#include <sys/types.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <signal.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#ifndef __STDC__
#define const /**/
#endif
#define MAPSIZE (8 * 1024)
/* Don't make these automatic vars or we will have to walk back up the
stack to access them. */
char *buf1;
char *buf2;
int coremaker_data = 1; /* In Data section */
int coremaker_bss; /* In BSS section */
/* Place a chunk of memory before coremaker_ro to improve the chances
that coremaker_ro will end up on it's own page. See:
https://sourceware.org/pipermail/gdb-patches/2020-May/168168.html
https://sourceware.org/pipermail/gdb-patches/2020-May/168170.html */
const unsigned char filler_ro[MAPSIZE] = {1, 2, 3, 4, 5, 6, 7, 8};
const int coremaker_ro = 201; /* In Read-Only Data section */
/* Note that if the mapping fails for any reason, we set buf2
to -1 and the testsuite notices this and reports it as
a failure due to a mapping error. This way we don't have
to test for specific errors when running the core maker. */
void
mmapdata ()
{
int j, fd;
/* Allocate and initialize a buffer that will be used to write
the file that is later mapped in. */
buf1 = (char *) malloc (MAPSIZE);
for (j = 0; j < MAPSIZE; ++j)
{
buf1[j] = j;
}
/* Write the file to map in */
fd = open ("coremmap.data", O_CREAT | O_RDWR, 0666);
if (fd == -1)
{
perror ("coremmap.data open failed");
buf2 = (char *) -1;
return;
}
write (fd, buf1, MAPSIZE);
/* Now map the file into our address space as buf2 */
buf2 = (char *) mmap (0, MAPSIZE, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
if (buf2 == (char *) MAP_FAILED)
{
perror ("mmap failed");
return;
}
/* Verify that the original data and the mapped data are identical.
If not, we'd rather fail now than when trying to access the mapped
data from the core file. */
for (j = 0; j < MAPSIZE; ++j)
{
if (buf1[j] != buf2[j])
{
fprintf (stderr, "mapped data is incorrect");
buf2 = (char *) -1;
return;
}
}
/* Touch buf2 so kernel writes it out into 'core'. */
buf2[0] = buf1[0];
}
void
func2 ()
{
int coremaker_local[5];
int i;
#ifdef SA_FULLDUMP
/* Force a corefile that includes the data section for AIX. */
{
struct sigaction sa;
sigaction (SIGABRT, (struct sigaction *)0, &sa);
sa.sa_flags |= SA_FULLDUMP;
sigaction (SIGABRT, &sa, (struct sigaction *)0);
}
#endif
/* Make sure that coremaker_local doesn't get optimized away. */
for (i = 0; i < 5; i++)
coremaker_local[i] = i;
coremaker_bss = 0;
for (i = 0; i < 5; i++)
coremaker_bss += coremaker_local[i];
coremaker_data = coremaker_ro + 1;
abort ();
}
void
func1 ()
{
func2 ();
}
int
main (int argc, char **argv)
{
if (argc == 2 && strcmp (argv[1], "sleep") == 0)
{
sleep (60);
return 0;
}
mmapdata ();
func1 ();
return 0;
}
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