gdbstub: Implement write memory (M pkt) with new infra

Signed-off-by: Jon Doron <arilou@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Message-Id: <20190529064148.19856-11-arilou@gmail.com>
Signed-off-by: Alex Bennée <alex.bennee@linaro.org>

gdbstub.c

@@ -1706,6 +1706,31 @@ static void handle_get_reg(GdbCmdContext *gdb_ctx, void *user_ctx)
     put_packet(gdb_ctx->s, gdb_ctx->str_buf);
 }
 
+static void handle_write_mem(GdbCmdContext *gdb_ctx, void *user_ctx)
+{
+    if (gdb_ctx->num_params != 3) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    /* hextomem() reads 2*len bytes */
+    if (gdb_ctx->params[1].val_ull > strlen(gdb_ctx->params[2].data) / 2) {
+        put_packet(gdb_ctx->s, "E22");
+        return;
+    }
+
+    hextomem(gdb_ctx->mem_buf, gdb_ctx->params[2].data,
+             gdb_ctx->params[1].val_ull);
+    if (target_memory_rw_debug(gdb_ctx->s->g_cpu, gdb_ctx->params[0].val_ull,
+                               gdb_ctx->mem_buf,
+                               gdb_ctx->params[1].val_ull, true)) {
+        put_packet(gdb_ctx->s, "E14");
+        return;
+    }
+
+    put_packet(gdb_ctx->s, "OK");
+}
+
 static int gdb_handle_packet(GDBState *s, const char *line_buf)
 {
     CPUState *cpu;
@@ -1914,24 +1939,14 @@ static int gdb_handle_packet(GDBState *s, const char *line_buf)
         }
         break;
     case 'M':
-        addr = strtoull(p, (char **)&p, 16);
-        if (*p == ',')
-            p++;
-        len = strtoull(p, (char **)&p, 16);
-        if (*p == ':')
-            p++;
-
-        /* hextomem() reads 2*len bytes */
-        if (len > strlen(p) / 2) {
-            put_packet (s, "E22");
-            break;
-        }
-        hextomem(mem_buf, p, len);
-        if (target_memory_rw_debug(s->g_cpu, addr, mem_buf, len,
-                                   true) != 0) {
-            put_packet(s, "E14");
-        } else {
-            put_packet(s, "OK");
+        {
+            static const GdbCmdParseEntry write_mem_cmd_desc = {
+                .handler = handle_write_mem,
+                .cmd = "M",
+                .cmd_startswith = 1,
+                .schema = "L,L:s0"
+            };
+            cmd_parser = &write_mem_cmd_desc;
         }
         break;
     case 'p':