--- /dev/null
+// -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
+// vim: ts=8 sw=2 smarttab
+/*
+ * Ceph - scalable distributed file system
+ *
+ * This is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License version 2.1, as published by the Free Software
+ * Foundation. See file COPYING.
+ */
+
+// install the librados-dev and librbd package to get this
+#include <rados/librados.hpp>
+#include <rbd/librbd.hpp>
+#include <iostream>
+#include <string>
+#include <sstream>
+
+int main(int argc, const char **argv)
+{
+ int ret = 0;
+
+ // we will use all of these below
+ const char *pool_name = "hello_world_pool";
+ std::string hello("hello world!");
+ std::string object_name("hello_object");
+ librados::IoCtx io_ctx;
+
+ // first, we create a Rados object and initialize it
+ librados::Rados rados;
+ {
+ ret = rados.init("admin"); // just use the client.admin keyring
+ if (ret < 0) { // let's handle any error that might have come back
+ std::cerr << "couldn't initialize rados! error " << ret << std::endl;
+ ret = EXIT_FAILURE;
+ goto out;
+ } else {
+ std::cout << "we just set up a rados cluster object" << std::endl;
+ }
+ }
+
+ /*
+ * Now we need to get the rados object its config info. It can
+ * parse argv for us to find the id, monitors, etc, so let's just
+ * use that.
+ */
+ {
+ ret = rados.conf_parse_argv(argc, argv);
+ if (ret < 0) {
+ // This really can't happen, but we need to check to be a good citizen.
+ std::cerr << "failed to parse config options! error " << ret << std::endl;
+ ret = EXIT_FAILURE;
+ goto out;
+ } else {
+ std::cout << "we just parsed our config options" << std::endl;
+ // We also want to apply the config file if the user specified
+ // one, and conf_parse_argv won't do that for us.
+ for (int i = 0; i < argc; ++i) {
+ if ((strcmp(argv[i], "-c") == 0) || (strcmp(argv[i], "--conf") == 0)) {
+ ret = rados.conf_read_file(argv[i+1]);
+ if (ret < 0) {
+ // This could fail if the config file is malformed, but it'd be hard.
+ std::cerr << "failed to parse config file " << argv[i+1]
+ << "! error" << ret << std::endl;
+ ret = EXIT_FAILURE;
+ goto out;
+ }
+ break;
+ }
+ }
+ }
+ }
+
+ /*
+ * next, we actually connect to the cluster
+ */
+ {
+ ret = rados.connect();
+ if (ret < 0) {
+ std::cerr << "couldn't connect to cluster! error " << ret << std::endl;
+ ret = EXIT_FAILURE;
+ goto out;
+ } else {
+ std::cout << "we just connected to the rados cluster" << std::endl;
+ }
+ }
+
+ /*
+ * let's create our own pool instead of scribbling over real data.
+ * Note that this command creates pools with default PG counts specified
+ * by the monitors, which may not be appropriate for real use -- it's fine
+ * for testing, though.
+ */
+ {
+ ret = rados.pool_create(pool_name);
+ if (ret < 0) {
+ std::cerr << "couldn't create pool! error " << ret << std::endl;
+ return EXIT_FAILURE;
+ } else {
+ std::cout << "we just created a new pool named " << pool_name << std::endl;
+ }
+ }
+
+ /*
+ * create an "IoCtx" which is used to do IO to a pool
+ */
+ {
+ ret = rados.ioctx_create(pool_name, io_ctx);
+ if (ret < 0) {
+ std::cerr << "couldn't set up ioctx! error " << ret << std::endl;
+ ret = EXIT_FAILURE;
+ goto out;
+ } else {
+ std::cout << "we just created an ioctx for our pool" << std::endl;
+ }
+ }
+
+ /*
+ * create an rbd image and write data to it
+ */
+ {
+ std::string name = "librbd_test";
+ uint64_t size = 2 << 20;
+ int order = 0;
+ librbd::RBD rbd;
+ librbd::Image image;
+
+ ret = rbd.create(io_ctx, name.c_str(), size, &order);
+ if (ret < 0) {
+ std::cerr << "couldn't create an rbd image! error " << ret << std::endl;
+ ret = EXIT_FAILURE;
+ goto out;
+ } else {
+ std::cout << "we just created an rbd image" << std::endl;
+ }
+
+ ret = rbd.open(io_ctx, image, name.c_str(), NULL);
+ if (ret < 0) {
+ std::cerr << "couldn't open the rbd image! error " << ret << std::endl;
+ ret = EXIT_FAILURE;
+ goto out;
+ } else {
+ std::cout << "we just opened the rbd image" << std::endl;
+ }
+
+ int TEST_IO_SIZE = 512;
+ char test_data[TEST_IO_SIZE + 1];
+ int i;
+
+ for (i = 0; i < TEST_IO_SIZE; ++i) {
+ test_data[i] = (char) (rand() % (126 - 33) + 33);
+ }
+ test_data[TEST_IO_SIZE] = '\0';
+
+ size_t len = strlen(test_data);
+ ceph::bufferlist bl;
+ bl.append(test_data, len);
+
+ ret = image.write(0, len, bl);
+ if (ret < 0) {
+ std::cerr << "couldn't write to the rbd image! error " << ret << std::endl;
+ ret = EXIT_FAILURE;
+ goto out;
+ } else {
+ std::cout << "we just wrote data to our rbd image " << std::endl;
+ }
+
+ /*
+ * let's read the image and compare it to the data we wrote
+ */
+ ceph::bufferlist bl_r;
+ int read;
+ read = image.read(0, TEST_IO_SIZE, bl_r);
+ if (read < 0) {
+ std::cerr << "we couldn't read data from the image! error" << std::endl;
+ ret = EXIT_FAILURE;
+ goto out;
+ }
+
+ std::string bl_res(bl_r.c_str(), read);
+
+ int res = memcmp(bl_res.c_str(), test_data, TEST_IO_SIZE);
+ if (res != 0) {
+ std::cerr << "what we read didn't match expected! error" << std::endl;
+ } else {
+ std::cout << "we read our data on the image successfully" << std::endl;
+ }
+
+ image.close();
+
+ /*
+ *let's now delete the image
+ */
+ ret = rbd.remove(io_ctx, name.c_str());
+ if (ret < 0) {
+ std::cerr << "failed to delete rbd image! error " << ret << std::endl;
+ ret = EXIT_FAILURE;
+ goto out;
+ } else {
+ std::cout << "we just deleted our rbd image " << std::endl;
+ }
+ }
+
+ ret = EXIT_SUCCESS;
+ out:
+ /*
+ * And now we're done, so let's remove our pool and then
+ * shut down the connection gracefully.
+ */
+ int delete_ret = rados.pool_delete(pool_name);
+ if (delete_ret < 0) {
+ // be careful not to
+ std::cerr << "We failed to delete our test pool!" << std::endl;
+ ret = EXIT_FAILURE;
+ }
+
+ rados.shutdown();
+
+ return ret;
+}
projects / ceph.git / commitdiff