Re: [PATCH v4 20/23] util: add support for formatting a workload name in messages

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 25/9/25 11:44, Daniel P. Berrangé wrote:
> The error_report function can include the guest name in any
> messages it prints. The qemu_log function has no equivalent
> behaviour.
> 
> This introduces support for a "workload name" in the new
> messages API, which in the case of system emulators will
> be the guest name. The possibility of defining a workload
> name for other binaries is left as an exercise for the
> future.
> 
> This change has no impact on the output of the error_report
> function, but will change the qemu_log function. This can
> be easily seen with the 'log' trace backend, and how it is
> now more closely matching error_report output.
> 
> Before:
> 
>    # qemu-system-x86_64 -msg guest-name=on -name blah -object tls-creds-x509,id=t0,dir=fish -d 'trace:qcrypto*'
>    qcrypto_tls_creds_x509_load TLS creds x509 load creds=0x55b3af3fd870 dir=fish
>    qcrypto_tls_creds_get_path TLS creds path creds=0x55b3af3fd870 filename=ca-cert.pem path=<none>
>    blah qemu-system-x86_64: Unable to access credentials fish/ca-cert.pem: No such file or directory
> 
> After:
> 
>    # qemu-system-x86_64 -msg guest-name=on -name blah -object tls-creds-x509,id=t0,dir=fish -d 'trace:qcrypto*'
>    blah qcrypto_tls_creds_x509_load TLS creds x509 load creds=0x55b3af3fd870 dir=fish
>    blah qcrypto_tls_creds_get_path TLS creds path creds=0x55b3af3fd870 filename=ca-cert.pem path=<none>
>    blah qemu-system-x86_64: Unable to access credentials fish/ca-cert.pem: No such file or directory
> 
> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
> ---
>   include/qemu/error-report.h |  3 ---
>   include/qemu/message.h      | 10 ++++++++++
>   system/vl.c                 |  6 ++++--
>   util/error-report.c         |  7 -------
>   util/message.c              | 11 +++++++++++
>   5 files changed, 25 insertions(+), 12 deletions(-)


>   void qmessage_context_print(FILE *fp)
>   {
>       if (message_format & QMESSAGE_FORMAT_TIMESTAMP) {
> @@ -19,4 +25,9 @@ void qmessage_context_print(FILE *fp)
>           g_autofree char *timestr = g_date_time_format_iso8601(dt);
>           fprintf(fp, "%s ", timestr);
>       }
> +
> +    if ((message_format & QMESSAGE_FORMAT_WORKLOAD_NAME) &&
> +        message_workloadname) {
> +        fprintf(fp, "%s ", message_workloadname);

Here also no formatting used; use fputs + fputc?

> +    }
>   }