# Copyright 2020-2021 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/>.

# Tests of core file memory accesses when mmap() has been used to
# create a "hole" of zeroes over pre-existing memory regions.  See
# coremaker2.c for details.

# are we on a target board
if ![isnative] then {
    return
}

# Some of these tests will only work on GNU/Linux due to the
# fact that Linux core files includes a section describing
# memory address to file mappings.  We'll use set_up_xfail for the
# affected tests.  As other targets become supported, the condition
# can be changed accordingly.

set xfail 0
if { ![istarget *-linux*] } {
    set xfail 1
}

standard_testfile coremaker2.c

if {[build_executable $testfile.exp $testfile $srcfile debug] == -1} {
    untested "failed to compile"
    return -1
}

set corefile [core_find $binfile {}]
if {$corefile == ""} {
    return 0
}

gdb_start
gdb_reinitialize_dir $srcdir/$subdir
gdb_load ${binfile}

# Attempt to load the core file.

gdb_test_multiple "core-file $corefile" "core-file command" {
    -re ".* program is being debugged already.*y or n. $" {
	# gdb_load may connect us to a gdbserver.
	send_gdb "y\n"
	exp_continue
    }
    -re "Core was generated by .*corefile.*\r\n\#0  .*\(\).*\r\n$gdb_prompt $" {
	pass "core-file command"
    }
    -re "Core was generated by .*\r\n\#0  .*\(\).*\r\n$gdb_prompt $" {
	pass "core-file command (with bad program name)"
    }
    -re ".*registers from core file: File in wrong format.* $" {
	fail "core-file command (could not read registers from core file)"
    }
}

# Perform the "interesting" tests which check the contents of certain
# memory regions.

proc do_tests { } {
    global xfail

    # Check contents of beginning of buf_rw and buf_ro.

    gdb_test {print/x buf_rw[0]@4} {\{0x6b, 0x6b, 0x6b, 0x6b\}}
    gdb_test {print/x buf_ro[0]@4} {\{0xc5, 0xc5, 0xc5, 0xc5\}}

    # Check for correct contents at beginning of mbuf_rw and mbuf_ro.

    gdb_test {print/x mbuf_rw[0]@4} {\{0x0, 0x0, 0x0, 0x0\}}

    if { $xfail } { setup_xfail "*-*-*" }
    gdb_test {print/x mbuf_ro[0]@4} {\{0x0, 0x0, 0x0, 0x0\}}

    # Check contents of mbuf_rw and mbuf_ro at the end of these regions.

    gdb_test {print/x mbuf_rw[pagesize-4]@4} {\{0x0, 0x0, 0x0, 0x0\}}

    if { $xfail } { setup_xfail "*-*-*" }
    gdb_test {print/x mbuf_ro[pagesize-4]@4} {\{0x0, 0x0, 0x0, 0x0\}}

    # Check contents of mbuf_rw and mbuf_ro, right before the hole,
    # overlapping into the beginning of these mmap'd regions.

    gdb_test {print/x mbuf_rw[-3]@6} {\{0x6b, 0x6b, 0x6b, 0x0, 0x0, 0x0\}}

    if { $xfail } { setup_xfail "*-*-*" }
    gdb_test {print/x mbuf_ro[-3]@6} {\{0xc5, 0xc5, 0xc5, 0x0, 0x0, 0x0\}}

    # Likewise, at the end of the mbuf_rw and mbuf_ro, with overlap.

    # If this test FAILs, it's probably a genuine bug unrelated to whether
    # the core file includes a section describing memory address to file
    # mappings or not.  (So don't xfail it!)
    gdb_test {print/x mbuf_rw[pagesize-3]@6} {\{0x0, 0x0, 0x0, 0x6b, 0x6b, 0x6b\}}

    if { $xfail } { setup_xfail "*-*-*" }
    gdb_test {print/x mbuf_ro[pagesize-3]@6} {\{0x0, 0x0, 0x0, 0xc5, 0xc5, 0xc5\}}

    # Check contents of (what should be) buf_rw and buf_ro immediately after
    # mbuf_rw and mbuf_ro holes.

    gdb_test {print/x mbuf_rw[pagesize]@4} {\{0x6b, 0x6b, 0x6b, 0x6b\}}
    gdb_test {print/x mbuf_ro[pagesize]@4} {\{0xc5, 0xc5, 0xc5, 0xc5\}}

    # Check contents at ends of buf_rw and buf_rw.

    gdb_test {print/x buf_rw[sizeof(buf_rw)-4]@4} {\{0x6b, 0x6b, 0x6b, 0x6b\}}
    gdb_test {print/x buf_ro[sizeof(buf_ro)-4]@4} {\{0xc5, 0xc5, 0xc5, 0xc5\}}
}

# Run tests with kernel-produced core file.

with_test_prefix "kernel core" {
    do_tests
}

# Verify that "maint print core-file-backed-mappings" exists and does
# not crash GDB.  If it produces any output at all, make sure that
# that output at least mentions binfile.

set test "maint print core-file-backed-mappings"
gdb_test_multiple $test "" {
    -re ".*$binfile.*$gdb_prompt $" {
	pass $test
    }
    -re "^$test\[\r\n\]*$gdb_prompt $" {
	pass "$test (no output)"
    }
}

# Test again with executable renamed during loading of core file.

with_test_prefix "renamed binfile" {
    # Don't load $binfile in this call to clean_restart.  (BFD will
    # complain that $binfile has disappeared after the rename if it's
    # loaded first.)
    clean_restart

    # Rename $binfile so that it won't be found during loading of
    # the core file.
    set hide_binfile [standard_output_file "${testfile}.hide"]
    remote_exec host "mv -f $binfile $hide_binfile"

    # Load core file - check that a warning is printed.
    global xfail
    if { $xfail } { setup_xfail "*-*-*" }
    gdb_test "core-file $corefile" \
	"warning: Can't open file.*during.* note processing.*Core was generated by .*\#0  .*\(\)" \
	"load core file without having first loaded binfile"

    # Restore $binfile and then load it.
    remote_exec host "mv -f $hide_binfile $binfile"
    gdb_load ${binfile}

    do_tests
}

# Restart and run to the abort call.

clean_restart $binfile

if ![runto_main] then {
    return
}

gdb_breakpoint [gdb_get_line_number "abort"]
gdb_continue_to_breakpoint "at abort"

# Do not execute abort call; instead, invoke gcore command to make a
# gdb-produced core file.

set corefile [standard_output_file gcore.test]
set core_supported [gdb_gcore_cmd "$corefile" "save a corefile"]
if {!$core_supported} {
  return
}

# maint print-core-file-backed-mappings shouldn't produce any output
# when not debugging a core file.

gdb_test_no_output "maint print core-file-backed-mappings" \
    "maint print core-file-backed-mapping with no core file"

clean_restart $binfile

set core_loaded [gdb_core_cmd "$corefile" "re-load generated corefile"]
if { $core_loaded == -1 } {
    # No use proceeding from here.
    return
}

# Run tests using gcore-produced core file.

with_test_prefix "gcore core" {
    do_tests
}