tests: Add qemucapsprobe helper

Adding new *.replies files for qemucapabilitiestest or updating the
files when libvirt adds an additional QMP command into the probing
process is quite painful. The goal of the new qemucapsprobe command is
to make this process as easy as

    tests/qemucapsprobe /path/to/qemu/binary >caps.replies

Signed-off-by: Jiri Denemark <jdenemar@redhat.com>

tests/Makefile.am

@@ -261,6 +261,7 @@ test_programs += qemuxml2argvtest qemuxml2xmltest \
 	qemumonitortest qemumonitorjsontest qemuhotplugtest \
 	qemuagenttest qemucapabilitiestest qemucaps2xmltest \
 	qemucommandutiltest
+test_helpers += qemucapsprobe
 endif WITH_QEMU
 
 if WITH_LXC
@@ -426,6 +427,7 @@ test_libraries += libqemumonitortestutils.la \
 		libqemutestdriver.la \
 		qemuxml2argvmock.la \
 		qemucaps2xmlmock.la \
+		qemucapsprobemock.la \
 		$(NULL)
 endif WITH_QEMU
 
@@ -603,6 +605,17 @@ qemucapabilitiestest_SOURCES = \
 qemucapabilitiestest_LDADD = libqemumonitortestutils.la \
 	$(qemu_LDADDS) $(LDADDS)
 
+qemucapsprobe_SOURCES = \
+	qemucapsprobe.c
+qemucapsprobe_LDADD = \
+	libqemutestdriver.la $(LDADDS)
+
+qemucapsprobemock_la_SOURCES = \
+	qemucapsprobemock.c
+qemucapsprobemock_la_CFLAGS = $(AM_CFLAGS)
+qemucapsprobemock_la_LDFLAGS = $(MOCKLIBS_LDFLAGS)
+qemucapsprobemock_la_LIBADD = $(MOCKLIBS_LIBS)
+
 qemucommandutiltest_SOURCES = \
 	qemucommandutiltest.c \
 	testutils.c testutils.h \

tests/qemucapabilitiestest.c

@@ -194,6 +194,11 @@ mymain(void)
     DO_TEST("caps_2.5.0-1");
     DO_TEST("caps_2.6.0-1");
 
+    /*
+     * Run "tests/qemucapsprobe /path/to/qemu/binary >foo.replies"
+     * to generate updated or new *.replies data files.
+     */
+
     qemuTestDriverFree(&driver);
 
     return (ret == 0) ? EXIT_SUCCESS : EXIT_FAILURE;

tests/qemucapsprobe.c

@@ -0,0 +1,82 @@
+/*
+ * Copyright (C) 2016 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Author: Jiri Denemark <jdenemar@redhat.com>
+ */
+
+#include <config.h>
+
+#include "testutils.h"
+#include "internal.h"
+#include "virthread.h"
+#include "qemu/qemu_capabilities.h"
+#define __QEMU_CAPSRIV_H_ALLOW__ 1
+#include "qemu/qemu_capspriv.h"
+
+#define VIR_FROM_THIS VIR_FROM_NONE
+
+
+static void
+eventLoop(void *opaque ATTRIBUTE_UNUSED)
+{
+    while (1) {
+        if (virEventRunDefaultImpl() < 0) {
+            virErrorPtr err = virGetLastError();
+            fprintf(stderr, "Failed to run event loop: %s\n",
+                    err && err->message ? err->message : "Unknown error");
+        }
+    }
+}
+
+
+int
+main(int argc, char **argv)
+{
+    virThread thread;
+    virQEMUCapsPtr caps;
+
+    VIRT_TEST_PRELOAD(abs_builddir "/.libs/qemucapsprobemock.so");
+
+    if (argc != 2) {
+        fprintf(stderr, "%s QEMU_binary\n", argv[0]);
+        return EXIT_FAILURE;
+    }
+
+    if (virThreadInitialize() < 0 ||
+        virInitialize() < 0) {
+        fprintf(stderr, "Failed to initialize libvirt");
+        return EXIT_FAILURE;
+    }
+
+    if (virEventRegisterDefaultImpl() < 0) {
+        virErrorPtr err = virGetLastError();
+        fprintf(stderr, "Failed to register event implementation: %s\n",
+                err && err->message ? err->message: "Unknown error");
+        return EXIT_FAILURE;
+    }
+
+    if (virThreadCreate(&thread, false, eventLoop, NULL) < 0)
+        return EXIT_FAILURE;
+
+    if (!(caps = virQEMUCapsNewForBinaryInternal(argv[1], "/tmp", NULL,
+                                                 -1, -1, true)))
+        return EXIT_FAILURE;
+
+    virObjectUnref(caps);
+
+    return EXIT_SUCCESS;
+}

tests/qemucapsprobemock.c

@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2016 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library.  If not, see
+ * <http://www.gnu.org/licenses/>.
+ *
+ * Author: Jiri Denemark <jdenemar@redhat.com>
+ */
+
+#include <config.h>
+#include <stdio.h>
+#include <dlfcn.h>
+
+#include "internal.h"
+#include "viralloc.h"
+#include "virjson.h"
+#include "qemu/qemu_monitor.h"
+#include "qemu/qemu_monitor_json.h"
+
+#define REAL_SYM(realFunc)                                                  \
+    do {                                                                    \
+        if (!realFunc && !(realFunc = dlsym(RTLD_NEXT, __FUNCTION__))) {    \
+            fprintf(stderr, "Cannot find real '%s' symbol\n",               \
+                    __FUNCTION__);                                          \
+            abort();                                                        \
+        }                                                                   \
+    } while (0)
+
+
+static int (*realQemuMonitorSend)(qemuMonitorPtr mon,
+                                  qemuMonitorMessagePtr msg);
+
+int
+qemuMonitorSend(qemuMonitorPtr mon,
+                qemuMonitorMessagePtr msg)
+{
+    REAL_SYM(realQemuMonitorSend);
+
+    fprintf(stderr, "%s", msg->txBuffer);
+
+    return realQemuMonitorSend(mon, msg);
+}
+
+
+static int (*realQemuMonitorJSONIOProcessLine)(qemuMonitorPtr mon,
+                                               const char *line,
+                                               qemuMonitorMessagePtr msg);
+
+int
+qemuMonitorJSONIOProcessLine(qemuMonitorPtr mon,
+                             const char *line,
+                             qemuMonitorMessagePtr msg)
+{
+    virJSONValuePtr value = NULL;
+    char *json = NULL;
+    int ret;
+
+    REAL_SYM(realQemuMonitorJSONIOProcessLine);
+
+    ret = realQemuMonitorJSONIOProcessLine(mon, line, msg);
+
+    if (ret == 0 &&
+        (value = virJSONValueFromString(line)) &&
+        (json = virJSONValueToString(value, 1))) {
+        char *p;
+        bool skip = false;
+
+        for (p = json; *p; p++) {
+            if (skip && *p == '\n') {
+                continue;
+            } else {
+                skip = *p == '\n';
+                putchar(*p);
+            }
+        }
+        putchar('\n');
+    }
+
+    VIR_FREE(json);
+    virJSONValueFree(value);
+    return ret;
+}