Re: [libvirt] [PATCH 2/3] virsh: qemu-monitor-command: Don't print extra newline with --pretty
On Mon, Aug 01, 2016 at 06:30:07AM +0200, Peter Krempa wrote:
The prettified JSON string already contains a newline so don't
print
another one. This allows to pipe the json output (in conjunction with
the --quiet option) to files without having to truncate them afterwards.
---
tools/virsh-domain.c | 19 +++++++++----------
1 file changed, 9 insertions(+), 10 deletions(-)
diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c
index 6c1bc2f..45fce76 100644
--- a/tools/virsh-domain.c
+++ b/tools/virsh-domain.c
@@ -8944,6 +8944,7 @@ cmdQemuMonitorCommand(vshControl *ctl, const vshCmd *cmd)
virBuffer buf = VIR_BUFFER_INITIALIZER;
bool pad = false;
virJSONValuePtr pretty = NULL;
+ char *prettystr = NULL;
VSH_EXCLUSIVE_OPTIONS("hmp", "pretty");
@@ -8969,22 +8970,20 @@ cmdQemuMonitorCommand(vshControl *ctl, const vshCmd *cmd)
if (virDomainQemuMonitorCommand(dom, monitor_cmd, &result, flags) < 0)
goto cleanup;
- if (vshCommandOptBool(cmd, "pretty")) {
- char *tmp;
- pretty = virJSONValueFromString(result);
- if (pretty && (tmp = virJSONValueToString(pretty, true))) {
- VIR_FREE(result);
- result = tmp;
- } else {
- vshResetLibvirtError();
- }
+ if (vshCommandOptBool(cmd, "pretty") &&
+ (pretty = virJSONValueFromString(result)) &&
I find naming the variable pretty pretty confusing. virJSONValuePtr is
in machine-friendly format and while it has the potential to be
formatted as pretty, it is not pretty right now.
+ (prettystr = virJSONValueToString(pretty, true))) {
+ vshPrint(ctl, "%s", prettystr);
+ } else {
+ vshResetLibvirtError();
Resetting it even when --pretty was not specified feels strange.
Also, grouping the if (--pretty) condition with the virJSONValue error
checks makes the flow hard to read.
Do we need the fallback? AFAIK there are only two issues possible when
prettifying the string:
* the system is out of memory
possibly impossible, erroring out or even aborting virsh are
acceptable here
* virDomainQemuMonitorCommand did not return a JSON output
For a domain with JSON monitor, the remote side calls virJSONValueToString,
so this could only reasonably happen with a domain that only has HMP.
If we error out on the --hmp --pretty combination, we can error out
here too and do not need to fall back to raw output.
+ vshPrint(ctl, "%s\n", result);
}
- vshPrint(ctl, "%s\n", result);
There is also the option of keeping the \n in vshPrint and calling
virTrimSpaces on the prettyfied output.
Jan