#!/usr/bin/env bash
# Copyright (C) 2003-2024 Free Software Foundation, Inc.
# 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/>.
#
# Script to generate a core file of a running program.
# It starts up gdb, attaches to the given PID and invokes the gcore command.
#
# Need to check for -o option, but set default basename to "core".
prefix=core
# When the -a option is present, this may hold additional commands
# to ensure gdb dumps all mappings (OS dependent).
dump_all_cmds=()
while getopts :ao: opt; do
case "$opt" in
a)
case "$OSTYPE" in
linux*)
dump_all_cmds=("-ex" "set use-coredump-filter off")
dump_all_cmds+=("-ex" "set dump-excluded-mappings on")
;;
esac
;;
o)
prefix=$OPTARG
;;
*)
echo "usage: gcore [-a] [-o prefix] pid1 [pid2...pidN]"
exit 2
;;
esac
done
shift $((OPTIND-1))
if [ "$#" -eq "0" ]
then
echo "usage: gcore [-a] [-o prefix] pid1 [pid2...pidN]"
exit 2
fi
# Attempt to fetch the absolute path to the gcore script that was
# called.
binary_path=`dirname "$0"`
if test "x$binary_path" = x. ; then
# We got "." back as a path. This means the user executed
# the gcore script locally (i.e. ./gcore) or called the
# script via a shell interpreter (i.e. sh gcore).
binary_basename=`basename "$0"`
# If the gcore script was called like "sh gcore" and the script
# lives in the current directory, "which" will not give us "gcore".
# So first we check if the script is in the current directory
# before using the output of "which".
if test -f "$binary_basename" ; then
# We have a local gcore script in ".". This covers the case of
# doing "./gcore" or "sh gcore".
binary_path="."
else
# The gcore script was not found in ".", which means the script
# was called from somewhere else in $PATH by "sh gcore".
# Extract the correct path now.
binary_path_from_env=`which "$0"`
binary_path=`dirname "$binary_path_from_env"`
fi
fi
# Check if the GDB binary is in the expected path. If not, just
# quit with a message.
if [ ! -f "$binary_path/gdb" ]; then
echo "gcore: GDB binary (${binary_path}/gdb) not found"
exit 1
fi
# Initialise return code.
rc=0
# Loop through pids
for pid in "$@"
do
# `</dev/null' to avoid touching interactive terminal if it is
# available but not accessible as GDB would get stopped on SIGTTIN.
"$binary_path/gdb" </dev/null \
--nx --batch --readnever -iex 'set debuginfod enabled off' \
-ex "set pagination off" -ex "set height 0" -ex "set width 0" \
"${dump_all_cmds[@]}" \
-ex "attach $pid" -ex "gcore $prefix.$pid" -ex detach -ex quit
if [ -r "$prefix.$pid" ] ; then
rc=0
else
echo "gcore: failed to create $prefix.$pid"
rc=1
break
fi
done
exit $rc
Mini Shell