Re: [libvirt] [PATCH] qemu: use line breaks in command line args written to log

On 12/14/18 2:07 PM, Daniel P. Berrangé wrote: > The QEMU command line arguments are very long and currently all written > on a single line to /var/log/libvirt/qemu/$GUEST.log. This introduces > logic to add line breaks after every env variable and "-" optional > argument, and every positional argument. This will create a clearer log > file, which will in turn present better in bug reports when people cut + > paste from the log into a bug comment. > > An example log file entry now looks like this: > > 2018-12-14 12:57:03.677+0000: starting up libvirt version: 5.0.0, qemu version: 3.0.0qemu-3.0.0-1.fc29, kernel: 4.19.5-300.fc29.x86_64, hostname: localhost.localdomain > LC_ALL=C \ > PATH=/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin \ > HOME=/home/berrange \ > USER=berrange \ > LOGNAME=berrange \ > QEMU_AUDIO_DRV=none \ > /usr/bin/qemu-system-ppc64 \ > -name guest=guest,debug-threads=on \ > -S \ > -object secret,id=masterKey0,format=raw,file=/home/berrange/.config/libvirt/qemu/lib/domain-33-guest/master-key.aes \ > -machine pseries-2.10,accel=tcg,usb=off,dump-guest-core=off \ > -m 1024 \ > -realtime mlock=off \ > -smp 1,sockets=1,cores=1,threads=1 \ > -uuid c8a74977-ab18-41d0-ae3b-4041c7fffbcd \ > -display none \ > -no-user-config \ > -nodefaults \ > -chardev socket,id=charmonitor,fd=23,server,nowait \ > -mon chardev=charmonitor,id=monitor,mode=control \ > -rtc base=utc \ > -no-shutdown \ > -boot strict=on \ > -device qemu-xhci,id=usb,bus=pci.0,addr=0x1 \ > -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x2 \ > -sandbox on,obsolete=deny,elevateprivileges=deny,spawn=deny,resourcecontrol=deny \ > -msg timestamp=on > 2018-12-14 12:57:03.730+0000: shutting down, reason=failed > > Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com&gt; > --- > docs/internals/command.html.in | 2 +- > src/bhyve/bhyve_driver.c | 4 +- > src/qemu/qemu_driver.c | 2 +- > src/qemu/qemu_interface.c | 2 +- > src/qemu/qemu_process.c | 2 +- > src/security/security_apparmor.c | 2 +- > src/util/vircommand.c | 19 ++++++++-- > src/util/vircommand.h | 2 +- > src/util/virfirewall.c | 2 +- > tests/bhyvexml2argvtest.c | 4 +- > tests/commanddata/test26.log | 1 + > tests/commandtest.c | 64 +++++++++++++++++++++++++++++++- > tests/qemuxml2argvtest.c | 2 +- > tests/storagepoolxml2argvtest.c | 2 +- > tests/storagevolxml2argvtest.c | 4 +- > 15 files changed, 95 insertions(+), 19 deletions(-) > create mode 100644 tests/commanddata/test26.log > > @@ -1991,11 +1993,22 @@ virCommandToString(virCommandPtr cmd) > virBufferAdd(&buf, cmd->env[i], eq - cmd->env[i]); > virBufferEscapeShell(&buf, eq); > virBufferAddChar(&buf, ' '); > + if (linebreaks) > + virBufferAddLit(&buf, "\\\n"); > } > virBufferEscapeShell(&buf, cmd->args[0]); > for (i = 1; i < cmd->nargs; i++) { > virBufferAddChar(&buf, ' '); > + if (linebreaks) { > + /* Line break if this is a --arg or if > + * the previous arg was a positional option > + */ > + if (cmd->args[i][0] == '-' || > + !prevopt) > + virBufferAddLit(&buf, "\\\n"); > + } > virBufferEscapeShell(&buf, cmd->args[i]); > + prevopt = (cmd->args[i][0] == '-'); Unfortunately, cmd->args[i] can be NULL here. So I guess this needs to look slightly different:

for (i = 1; i < cmd->nargs; i++) { virBufferAddChar(&buf, ' '); if (!cmd->args[i]) continue; if (linebreaks) { /* Line break if this is a --arg or if * the previous arg was a positional option */ if (cmd->args[i][0] == '-' || !prevopt) virBufferAddLit(&buf, "\\\n"); } virBufferEscapeShell(&buf, cmd->args[i]); prevopt = (cmd->args[i][0] == '-'); } ACK if you fix this. Michal