[RFC PATCH 20/24] gdbstub: Expose functions to read registers

[Akihiko Odaki]

gdb_foreach_feature() enumerates features that are useful to identify
registers. gdb_read_register() actually reads registers.

Signed-off-by: Akihiko Odaki <akihiko.odaki@daynix.com>
---
 include/exec/gdbstub.h |  6 ++++++
 gdbstub/gdbstub.c      | 38 ++++++++++++++++++++++++++++++--------
 2 files changed, 36 insertions(+), 8 deletions(-)

diff --git a/include/exec/gdbstub.h b/include/exec/gdbstub.h
index cbd1e6ead4..5e5789f7bb 100644
--- a/include/exec/gdbstub.h
+++ b/include/exec/gdbstub.h
@@ -38,6 +38,12 @@ int gdbserver_start(const char *port_or_device);
 
 const GDBFeature *gdb_find_static_feature(const char *xmlname);
 
+void gdb_foreach_feature(CPUState *cpu,
+                         void (* callback)(void *, const GDBFeature *, int),
+                         void *opaque);
+
+int gdb_read_register(CPUState *cpu, GByteArray *buf, int reg, bool has_xml);
+
 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 caef6aabab..5f76ff7271 100644
--- a/gdbstub/gdbstub.c
+++ b/gdbstub/gdbstub.c
@@ -416,14 +416,32 @@ const GDBFeature *gdb_find_static_feature(const char 
*xmlname)
     return NULL;
 }
 
-static int gdb_read_register(CPUState *cpu, GByteArray *buf, int reg)
+void gdb_foreach_feature(CPUState *cpu,
+                         void (* callback)(void *, const GDBFeature *, int),
+                         void *opaque)
+{
+    CPUClass *cc = CPU_GET_CLASS(cpu);
+    GDBRegisterState *r;
+
+    if (!cc->gdb_core_feature) {
+        return;
+    }
+
+    callback(opaque, cc->gdb_core_feature, 0);
+
+    for (r = cpu->gdb_regs; r; r = r->next) {
+        callback(opaque, r->feature, r->base_reg);
+    }
+}
+
+int gdb_read_register(CPUState *cpu, GByteArray *buf, int reg, bool has_xml)
 {
     CPUClass *cc = CPU_GET_CLASS(cpu);
     CPUArchState *env = cpu->env_ptr;
     GDBRegisterState *r;
 
     if (reg < cc->gdb_num_core_regs) {
-        return cc->gdb_read_register(cpu, buf, reg, gdb_has_xml);
+        return cc->gdb_read_register(cpu, buf, reg, has_xml);
     }
 
     for (r = cpu->gdb_regs; r; r = r->next) {
@@ -434,14 +452,15 @@ static int gdb_read_register(CPUState *cpu, GByteArray 
*buf, int reg)
     return 0;
 }
 
-static int gdb_write_register(CPUState *cpu, uint8_t *mem_buf, int reg)
+static int gdb_write_register(CPUState *cpu, uint8_t *mem_buf, int reg,
+                              bool has_xml)
 {
     CPUClass *cc = CPU_GET_CLASS(cpu);
     CPUArchState *env = cpu->env_ptr;
     GDBRegisterState *r;
 
     if (reg < cc->gdb_num_core_regs) {
-        return cc->gdb_write_register(cpu, mem_buf, reg, gdb_has_xml);
+        return cc->gdb_write_register(cpu, mem_buf, reg, has_xml);
     }
 
     for (r = cpu->gdb_regs; r; r = r->next) {
@@ -1067,7 +1086,7 @@ static void handle_set_reg(GArray *params, void *user_ctx)
     reg_size = strlen(get_param(params, 1)->data) / 2;
     gdb_hextomem(gdbserver_state.mem_buf, get_param(params, 1)->data, 
reg_size);
     gdb_write_register(gdbserver_state.g_cpu, gdbserver_state.mem_buf->data,
-                       get_param(params, 0)->val_ull);
+                       get_param(params, 0)->val_ull, gdb_has_xml);
     gdb_put_packet("OK");
 }
 
@@ -1087,7 +1106,8 @@ static void handle_get_reg(GArray *params, void *user_ctx)
 
     reg_size = gdb_read_register(gdbserver_state.g_cpu,
                                  gdbserver_state.mem_buf,
-                                 get_param(params, 0)->val_ull);
+                                 get_param(params, 0)->val_ull,
+                                 gdb_has_xml);
     if (!reg_size) {
         gdb_put_packet("E14");
         return;
@@ -1174,7 +1194,8 @@ static void handle_write_all_regs(GArray *params, void 
*user_ctx)
     for (reg_id = 0;
          reg_id < gdbserver_state.g_cpu->gdb_num_g_regs && len > 0;
          reg_id++) {
-        reg_size = gdb_write_register(gdbserver_state.g_cpu, registers, 
reg_id);
+        reg_size = gdb_write_register(gdbserver_state.g_cpu, registers, reg_id,
+                                      gdb_has_xml);
         len -= reg_size;
         registers += reg_size;
     }
@@ -1192,7 +1213,8 @@ static void handle_read_all_regs(GArray *params, void 
*user_ctx)
     for (reg_id = 0; reg_id < gdbserver_state.g_cpu->gdb_num_g_regs; reg_id++) 
{
         len += gdb_read_register(gdbserver_state.g_cpu,
                                  gdbserver_state.mem_buf,
-                                 reg_id);
+                                 reg_id,
+                                 gdb_has_xml);
     }
     g_assert(len == gdbserver_state.mem_buf->len);
 
-- 
2.41.0