# Copyright 2017-2023 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/>.

# When debugging with "target remote |", the inferior's output is
# connected to a pipe, and if GDB doesn't flush the pipe while the
# inferior is running and the pipe becomes full, then the inferior
# deadlocks:
#
#  1. User sets breakpoint, and types "continue"
#
#  2. Inferior prints to stdout/stderr before reaching breakpoint
#     location.
#
#  3. The output pipe becomes full, so the inferior blocks forever in
#     the printf/write call.
#
#  4. The breakpoint is never reached.

require {!target_info exists gdb,noinferiorio}

standard_testfile

if [prepare_for_testing "failed to prepare" $testfile {} {debug}] {
    return -1
}

if {![runto_main]} {
    return
}

set printing_done_line [gdb_get_line_number "printing done"]
gdb_test "break $printing_done_line" ".*" "set breakpoint after printing"

send_gdb "continue\n"

set expected_lines 3000
set more 1
set i 0
while {$more} {
    set more 0
    gdb_expect {
	-i $inferior_spawn_id
	-ex "this is line number $i" {
	    incr i
           if {$i != $expected_lines} {
		set more 1
	    }
	}
    }
}

gdb_assert {$i == $expected_lines} "saw all lines"

set test "breakpoint reached"
gdb_test_multiple "" $test {
    -re "Breakpoint .* main .*$srcfile:$printing_done_line.*$gdb_prompt $" {
	pass $test
    }
}