[Buildroot] [PATCH v5 4/5] support/scripts/boot-qemu-image.py: boot Qemu images with Qemu-system.

[Romain Naour <romain.naour@gmail.com>]

Hi Yann, All,

Le 13/04/2020 ? 09:15, Yann E. MORIN a ?crit?:
> Romain, Jugurtha, All,
> 
> On 2020-02-17 21:50 +0100, Romain Naour spake thusly:
>> From: Jugurtha BELKALEM <jugurtha.belkalem@smile.fr>
>> This script is intended to be used by gitlab CI to test
>> at runtime Qemu images generated by Buildroot's Qemu defconfigs.
> [--SNIP--]
>> diff --git a/support/scripts/boot-qemu-image.py b/support/scripts/boot-qemu-image.py
>> new file mode 100755
>> index 0000000000..abaf88d446
>> --- /dev/null
>> +++ b/support/scripts/boot-qemu-image.py
>> @@ -0,0 +1,105 @@
>> +#!/usr/bin/env python3
>> +
>> +# This script expect to run from the Buildroot top directory.
>> +
>> +import pexpect
>> +import sys
>> +import os
>> +import re
>> +import shlex
>> +import shutil
>> +import subprocess
>> +
>> +argc = len(sys.argv)
>> +if not (argc == 2):
>> +    print("Error: incorrect number of arguments")
>> +    print("""Usage: boot-qemu-image.py <qemu_arch_defconfig>""")
>> +    sys.exit(1)
>> +
>> +defconfig_filename = sys.argv[1]
>> +
>> +# Ignore non Qemu defconfig
>> +if defconfig_filename.startswith('qemu_') is False:
>> +    sys.exit(0)
>> +
>> +qemu_start_script_filepath = os.path.join(os.getcwd(), 'output/images/start-qemu.sh')
>> +
>> +# Ignore if start-qemu.sh is missing, we can't test.
>> +if not os.path.exists(qemu_start_script_filepath):
>> +    print("Error: " + qemu_start_script_filepath) + " file is missing."
>> +    sys.exit(1)
>> +
>> +qemu_cmd = ""
>> +
>> +with open(qemu_start_script_filepath, 'r') as script_file:
>> +    for line in script_file:
>> +        if re.search("qemu-system", line):
>> +            qemu_cmd = line
>> +            break
>> +
>> +if not qemu_cmd:
>> +    print("Error: No QEMU command line found in " + qemu_start_script_filepath)
>> +    sys.exit(1)
> 
> Why do you extract the command line, and can't directly run the script?
> 
>> +# Replace bashism
>> +qemu_cmd = line.replace("${IMAGE_DIR}", "output/images")
> 
> This would avoid this dance...
> 
>> +# pexpect needs a list, convert a sting to a list and escape quoted substring.
>> +qemu_cmd = shlex.split(qemu_cmd)
> 
> ... as well as this one.
> 
>> +# Use host Qemu if provided by Buildroot.
>> +os.environ["PATH"] = os.getcwd() + "/output/host/bin" + os.pathsep + os.environ["PATH"]
> 
> And this one can be avoided too if the script is called with PATH
> properly set to include ${HOST_DIR}/bin. This should be easy, as this
> script is only expected to run from the gitlab-ci pipelines.
> 
>> +# Ignore when no Qemu emulation is available
>> +if not shutil.which(qemu_cmd[0]):
>> +    print("No " + qemu_cmd[0] + " binary available, THIS DEFCONFIG CAN NOT BE TESTED!")
>> +    sys.exit(0)

Extracting the qemu command line in the boot-qemu-image.py allowed to test if at
least one qemu-systemd-<arch> binary is present. Starting start-qemu.sh directly
crash the python script.

https://gitlab.com/kubu93/buildroot/-/jobs/509053135/artifacts/file/runtime-test.log

csky and or1k defconfig doesn't select any host-qemu and there is none installed
in the Buildroot Docker image used by gitlab CI.

It seems we need to catch the exception while calling pexpect.spawn(qemu_start...)

https://git.buildroot.net/buildroot/tree/support/scripts/boot-qemu-image.py#n22

Or just add this test in start-qemu.sh

Best regards,
Romain