qtest: add in-process incoming command handler

The handler allows a qtest client to send commands to the server by
directly calling a function, rather than using a file/CharBackend
Signed-off-by: NAlexander Bulekov <alxndr@bu.edu>
Reviewed-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NDarren Kenny <darren.kenny@oracle.com>
Message-id: 20200220041118.23264-9-alxndr@bu.edu
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

include/sysemu/qtest.h

@@ -28,5 +28,6 @@ void qtest_server_init(const char *qtest_chrdev, const char *qtest_log, Error **
 
 void qtest_server_set_send_handler(void (*send)(void *, const char *),
                                  void *opaque);
+void qtest_server_inproc_recv(void *opaque, const char *buf);
 
 #endif

qtest.c

@@ -804,3 +804,16 @@ bool qtest_driver(void)
 {
     return qtest_chr.chr != NULL;
 }
+
+void qtest_server_inproc_recv(void *dummy, const char *buf)
+{
+    static GString *gstr;
+    if (!gstr) {
+        gstr = g_string_new(NULL);
+    }
+    g_string_append(gstr, buf);
+    if (gstr->str[gstr->len - 1] == '\n') {
+        qtest_process_inbuf(NULL, gstr);
+        g_string_truncate(gstr, 0);
+    }
+}