#!/bin/sh
#
# Check effectiveness of umovestr memory caching.
#
# Copyright (c) 2017-2020 Dmitry V. Levin <ldv@strace.io>
# All rights reserved.
#
# SPDX-License-Identifier: GPL-2.0-or-later

. "${srcdir=.}/init.sh"

expected_count="${1:-2}"

check_prog grep
$STRACE -d -enone / > /dev/null 2> "$LOG" ||:
grep -x "[^:]*strace: PTRACE_GET_SYSCALL_INFO works" "$LOG" > /dev/null || {
	# PTRACE_GET_SYSCALL_INFO does not work
	case "$STRACE_ARCH:$MIPS_ABI" in
		ia64:|mips:o32)
		# ia64 invokes extra process_vm_readv syscalls to obtain syscall
		# arguments, see linux/ia64/get_syscall_args.c for details.
		# mips o32 obtains the first four syscalls arguments from registers
		# and invokes extra process_vm_readv syscalls to obtain remaining
		# syscall arguments, see linux/mips/get_syscall_args.c for details.
		skip_ "the test is not supported on $STRACE_ARCH yet"
		;;
	esac
}

run_strace_match_diff -e trace=writev

run_strace -qq -esignal=none -eprocess_vm_readv -z \
	-o '|grep -c ^process_vm_readv > count' \
	-- "$STRACE_EXE" -o "$LOG" $args > /dev/null

count="$(cat count)"
case "$count" in
	0) skip_ "$STRACE $args made no process_vm_readv syscall invocations" ;;
	$expected_count) ;;
	*) fail_ "$STRACE $args made $count != $expected_count process_vm_readv syscall invocations" ;;
esac