#!/bin/bash

# Install coredump handler which saves segfault data

# For debugging

dry_run=false

verbose=false

PATTERN_FILE="/proc/sys/kernel/core_pattern"

SAVED_PATTERN_DIR="@VAR_RUN@/abrt"

SAVED_PATTERN_FILE="@VAR_RUN@/abrt/saved_core_pattern"

HOOK_BIN="@libexecdir@/abrt-hook-ccpp"

# Must match percent_specifiers[] order in abrt-hook-ccpp.c:

PATTERN="|$HOOK_BIN %s %c %p %u %g %t %P %I %h %e"

# core_pipe_limit specifies how many dump_helpers can run at the same time

# 0 - means unlimited, but it's not guaranteed that /proc/<pid> of crashing

#     process will be available for dump_helper.

# 4 - means that 4 dump_helpers can run at the same time (the rest will also

#     run, but they will fail to read /proc/<pid>).

#

# This should be enough for ABRT, we can miss some crashes, but what are

# the odds that more processes crash at the same time? And moreover,

# do people want to save EVERY ONE of the crashes when they have

# a crash storm? I don't think so.

# The value of 4 has been recommended by nhorman.

#

CORE_PIPE_LIMIT_FILE="/proc/sys/kernel/core_pipe_limit"

CORE_PIPE_LIMIT="4"

start() {

	if ! $HOOK_BIN --test-config; then

		echo "Invalid configuration."

		exit 1

	fi

	cur=`cat "$PATTERN_FILE"`

	cur_first=`printf "%s" "$cur" | sed 's/ .*//'`

	$verbose && printf "cur:'%s'\n" "$cur"

	# Is it already installed?

	if test x"$cur_first" != x"|$HOOK_BIN"; then   # no

		# It is not installed

		mkdir -p -- "$SAVED_PATTERN_DIR"

		printf "%s\n" "$cur" >"$SAVED_PATTERN_FILE"

		# Install new handler

		$verbose && printf "Installing to %s:'%s'\n" "$PATTERN_FILE" "$PATTERN"

		$dry_run || echo "$PATTERN" >"$PATTERN_FILE"

		# Check core_pipe_limit and change it if it's 0,

		# otherwise the abrt-hook-ccpp won't be able to read /proc/<pid>

		# of the crashing process

		if test x"`cat "$CORE_PIPE_LIMIT_FILE"`" = x"0"; then

			echo "$CORE_PIPE_LIMIT" >"$CORE_PIPE_LIMIT_FILE"

		fi

	fi

}

stop() {

	if test -f "$SAVED_PATTERN_FILE"; then

		$verbose && printf "Restoring to %s:'%s'\n" "$PATTERN_FILE" "`cat "$SAVED_PATTERN_FILE"`"

		$dry_run || cat "$SAVED_PATTERN_FILE" >"$PATTERN_FILE"

	fi

}

status() {

	cur=`cat "$PATTERN_FILE"`

	cur_first=`printf "%s" "$cur" | sed 's/ .*//'`

	# Is it already installed?

	if test x"$cur_first" = x"|$HOOK_BIN"; then   # yes

		$verbose && printf "Installed\n"

		return 0

	else

		$verbose && printf "Not installed\n"

		return 1

	fi

}

case "$1" in

install)

	start

	;;

uninstall)

	stop

	;;

is-installed)

	status

	;;

*)

	echo $"Usage: $0 {install|uninstall|is-installed}"

	exit 2

esac