Re: [PATCH v2 06/53] hw/core: introduce 'format_state' callback to replace 'dump_state'

[Greg Kurz <groug@kaod.org>]

On Tue, 14 Sep 2021 15:19:55 +0100
Daniel P. Berrangé <berrange@redhat.com> wrote:

> The 'dump_state' callback assumes it will be outputting to a FILE
> object. This is fine for HMP, but not so useful for QMP. Introduce
> a new 'format_state' callback that returns a formatted GString
> instead.
> 
> Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
> ---

Reviewed-by: Greg Kurz <groug@kaod.org>

>  hw/core/cpu-common.c  | 15 +++++++++++++++
>  include/hw/core/cpu.h | 13 ++++++++++++-
>  2 files changed, 27 insertions(+), 1 deletion(-)
> 
> diff --git a/hw/core/cpu-common.c b/hw/core/cpu-common.c
> index e2f5a64604..c2cd33a817 100644
> --- a/hw/core/cpu-common.c
> +++ b/hw/core/cpu-common.c
> @@ -106,6 +106,21 @@ void cpu_dump_state(CPUState *cpu, FILE *f, int flags)
>      if (cc->dump_state) {
>          cpu_synchronize_state(cpu);
>          cc->dump_state(cpu, f, flags);
> +    } else if (cc->format_state) {
> +        g_autoptr(GString) buf = g_string_new("");
> +        cpu_synchronize_state(cpu);
> +        cc->format_state(cpu, buf, flags);
> +        qemu_fprintf(f, "%s", buf->str);
> +    }
> +}
> +
> +void cpu_format_state(CPUState *cpu, GString *buf, int flags)
> +{
> +    CPUClass *cc = CPU_GET_CLASS(cpu);
> +
> +    if (cc->format_state) {
> +        cpu_synchronize_state(cpu);
> +        cc->format_state(cpu, buf, flags);
>      }
>  }
>  
> diff --git a/include/hw/core/cpu.h b/include/hw/core/cpu.h
> index bc864564ce..1599ef9df3 100644
> --- a/include/hw/core/cpu.h
> +++ b/include/hw/core/cpu.h
> @@ -91,7 +91,8 @@ struct SysemuCPUOps;
>   * @reset_dump_flags: #CPUDumpFlags to use for reset logging.
>   * @has_work: Callback for checking if there is work to do.
>   * @memory_rw_debug: Callback for GDB memory access.
> - * @dump_state: Callback for dumping state.
> + * @dump_state: Callback for dumping state. Deprecated, use @format_state.
> + * @format_state: Callback for formatting state.
>   * @get_arch_id: Callback for getting architecture-dependent CPU ID.
>   * @set_pc: Callback for setting the Program Counter register. This
>   *       should have the semantics used by the target architecture when
> @@ -136,6 +137,7 @@ struct CPUClass {
>      int (*memory_rw_debug)(CPUState *cpu, vaddr addr,
>                             uint8_t *buf, int len, bool is_write);
>      void (*dump_state)(CPUState *cpu, FILE *, int flags);
> +    void (*format_state)(CPUState *cpu, GString *buf, int flags);
>      int64_t (*get_arch_id)(CPUState *cpu);
>      void (*set_pc)(CPUState *cpu, vaddr value);
>      int (*gdb_read_register)(CPUState *cpu, GByteArray *buf, int reg);
> @@ -537,6 +539,15 @@ enum CPUDumpFlags {
>   */
>  void cpu_dump_state(CPUState *cpu, FILE *f, int flags);
>  
> +/**
> + * cpu_format_state:
> + * @cpu: The CPU whose state is to be formatted.
> + * @buf: buffer to format state into
> + *
> + * Formats the CPU state.
> + */
> +void cpu_format_state(CPUState *cpu, GString *buf, int flags);
> +
>  #ifndef CONFIG_USER_ONLY
>  /**
>   * cpu_get_phys_page_attrs_debug: