vtest: expect explicit initialisation with name

this gets the cmdline passes to us

vtest/vtest.h

@@ -2,7 +2,7 @@
 #define VTEST_H
 
 #include <errno.h>
-int vtest_create_renderer(int fd);
+int vtest_create_renderer(int fd, uint32_t length);
 
 int vtest_send_caps(void);
 

vtest/vtest_protocol.h

@@ -24,6 +24,8 @@
 
 #define VCMD_RESOURCE_BUSY_WAIT 7
 
+/* pass the process cmd line for debugging */
+#define VCMD_CREATE_RENDERER 8
 /* get caps */
 /* 0 length cmd */
 /* resp VCMD_GET_CAPS + caps */

vtest/vtest_renderer.c

@@ -65,14 +65,25 @@ int vtest_block_read(int fd, void *buf, int size)
    return size;
 }
 
-int vtest_create_renderer(int fd)
+int vtest_create_renderer(int fd, uint32_t length)
 {
-    const char *vtestname = "vtestname";
+    char *vtestname;
     int ret;
 
     renderer.remote_fd = fd;
+
     virgl_renderer_init(&renderer, VIRGL_RENDERER_USE_EGL, &vtest_cbs);
 
+    vtestname = malloc(length);
+    if (!vtestname)
+      return -1;
+
+    ret = vtest_block_read(renderer.remote_fd, vtestname, length);
+    if (ret != length)
+	return -1;
+
+    fprintf(stderr, "string len is %d: %s\n", length, vtestname);
+
     ret = virgl_renderer_context_create(ctx_id, strlen(vtestname), vtestname);
     return ret;
 }

vtest/vtest_server.c

@@ -84,7 +84,7 @@ int run_renderer(int new_fd)
     int ret;
     uint32_t header[VTEST_HDR_SIZE];
     bool do_fence;
-    vtest_create_renderer(new_fd);
+    bool inited = false;
 again:
     ret = wait_for_socket_read(new_fd);
     if (ret < 0)
@@ -93,6 +93,12 @@ again:
     ret = vtest_block_read(new_fd, &header, sizeof(header));
 
     if (ret == 8) {
+      if (!inited) {
+	if (header[1] != VCMD_CREATE_RENDERER)
+	  goto fail;
+	ret = vtest_create_renderer(new_fd, header[0]);
+	inited = true;
+      }
       vtest_poll();
       do_fence = false;
       switch (header[1]) {
@@ -118,6 +124,7 @@ again:
 	break;
       case VCMD_RESOURCE_BUSY_WAIT:
 	ret = vtest_resource_busy_wait();
+	break;
       default:
 	break;
       }