gdb_find_feature() and gdb_find_feature_register() find registers.
gdb_read_register() actually reads registers.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
---
 include/exec/gdbstub.h |  5 +++++
 gdbstub/gdbstub.c      | 50 +++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 54 insertions(+), 1 deletion(-)

diff --git a/include/exec/gdbstub.h b/include/exec/gdbstub.h
index 340ab35d74..e6ba2a2886 100644
--- a/include/exec/gdbstub.h
+++ b/include/exec/gdbstub.h
@@ -69,6 +69,11 @@ void gdb_feature_builder_end(const GDBFeatureBuilder *builder);
 
 const GDBFeature *gdb_find_static_feature(const char *xmlname);
 
+int gdb_find_feature(CPUState *cpu, const char *name);
+int gdb_find_feature_register(CPUState *cpu, int feature, const char *name);
+
+int gdb_read_register(CPUState *cpu, GByteArray *buf, int reg);
+
 void gdb_set_stop_cpu(CPUState *cpu);
 
 /* in gdbstub-xml.c, generated by scripts/feature_to_c.py */
diff --git a/gdbstub/gdbstub.c b/gdbstub/gdbstub.c
index 60faae8b2b..fc780ae6fe 100644
--- a/gdbstub/gdbstub.c
+++ b/gdbstub/gdbstub.c
@@ -492,7 +492,55 @@ const GDBFeature *gdb_find_static_feature(const char *xmlname)
     g_assert_not_reached();
 }
 
-static int gdb_read_register(CPUState *cpu, GByteArray *buf, int reg)
+int gdb_find_feature(CPUState *cpu, const char *name)
+{
+    CPUClass *cc = CPU_GET_CLASS(cpu);
+    GDBRegisterState *r;
+
+    if (!cc->gdb_core_feature) {
+        return -1;
+    }
+
+    if (!strcmp(name, cc->gdb_core_feature->name)) {
+        return 0;
+    }
+
+    for (guint i = 0; i < cpu->gdb_regs->len; i++) {
+        r = &g_array_index(cpu->gdb_regs, GDBRegisterState, i);
+        if (!strcmp(name, r->feature->name)) {
+            return i + 1;
+        }
+    }
+
+    return -1;
+}
+
+int gdb_find_feature_register(CPUState *cpu, int feature, const char *name)
+{
+    CPUClass *cc = CPU_GET_CLASS(cpu);
+    const GDBFeature *p;
+    int base_reg;
+
+    if (feature) {
+        GDBRegisterState *r =
+            &g_array_index(cpu->gdb_regs, GDBRegisterState, feature - 1);
+        p = r->feature;
+        base_reg = r->base_reg;
+    } else {
+        p = cc->gdb_core_feature;
+        base_reg = 0;
+    }
+
+    for (int i = 0; i < p->num_regs; i++) {
+        if (p->regs[i] && !strcmp(name, p->regs[i])) {
+            return base_reg + i;
+        }
+    }
+
+    return -1;
+}
+
+int gdb_read_register(CPUState *cpu, GByteArray *buf, int reg)
 {
     CPUClass *cc = CPU_GET_CLASS(cpu);
     CPUArchState *env = cpu->env_ptr;
-- 
2.42.0