[PATCH 2/5] hw/core: introduce 'format_state' callback to replace 'dump_state'

["Daniel P. Berrangé" <berrange@redhat.com>]

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>
---
 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:
-- 
2.31.1