Adding upstream version 18.2.2.upstream/18.2.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 96 insertions, 0 deletions

diff --git a/src/rocksdb/examples/c_simple_example.c b/src/rocksdb/examples/c_simple_example.c
new file mode 100644
index 000000000..fe2f917b4
--- /dev/null
+++ b/src/rocksdb/examples/c_simple_example.c
@@ -0,0 +1,96 @@
+//  Copyright (c) 2011-present, Facebook, Inc.  All rights reserved.
+//  This source code is licensed under both the GPLv2 (found in the
+//  COPYING file in the root directory) and Apache 2.0 License
+//  (found in the LICENSE.Apache file in the root directory).
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <assert.h>
+
+#include "rocksdb/c.h"
+
+#if defined(OS_WIN)
+#include <Windows.h>
+#else
+#include <unistd.h>  // sysconf() - get CPU count
+#endif
+
+#if defined(OS_WIN)
+const char DBPath[] = "C:\\Windows\\TEMP\\rocksdb_c_simple_example";
+const char DBBackupPath[] =
+    "C:\\Windows\\TEMP\\rocksdb_c_simple_example_backup";
+#else
+const char DBPath[] = "/tmp/rocksdb_c_simple_example";
+const char DBBackupPath[] = "/tmp/rocksdb_c_simple_example_backup";
+#endif
+
+int main(int argc, char **argv) {
+  rocksdb_t *db;
+  rocksdb_backup_engine_t *be;
+  rocksdb_options_t *options = rocksdb_options_create();
+  // Optimize RocksDB. This is the easiest way to
+  // get RocksDB to perform well.
+#if defined(OS_WIN)
+  SYSTEM_INFO system_info;
+  GetSystemInfo(&system_info);
+  long cpus = system_info.dwNumberOfProcessors;
+#else
+  long cpus = sysconf(_SC_NPROCESSORS_ONLN);
+#endif
+  // Set # of online cores
+  rocksdb_options_increase_parallelism(options, (int)(cpus));
+  rocksdb_options_optimize_level_style_compaction(options, 0);
+  // create the DB if it's not already present
+  rocksdb_options_set_create_if_missing(options, 1);
+
+  // open DB
+  char *err = NULL;
+  db = rocksdb_open(options, DBPath, &err);
+  assert(!err);
+
+  // open Backup Engine that we will use for backing up our database
+  be = rocksdb_backup_engine_open(options, DBBackupPath, &err);
+  assert(!err);
+
+  // Put key-value
+  rocksdb_writeoptions_t *writeoptions = rocksdb_writeoptions_create();
+  const char key[] = "key";
+  const char *value = "value";
+  rocksdb_put(db, writeoptions, key, strlen(key), value, strlen(value) + 1,
+              &err);
+  assert(!err);
+  // Get value
+  rocksdb_readoptions_t *readoptions = rocksdb_readoptions_create();
+  size_t len;
+  char *returned_value =
+      rocksdb_get(db, readoptions, key, strlen(key), &len, &err);
+  assert(!err);
+  assert(strcmp(returned_value, "value") == 0);
+  free(returned_value);
+
+  // create new backup in a directory specified by DBBackupPath
+  rocksdb_backup_engine_create_new_backup(be, db, &err);
+  assert(!err);
+
+  rocksdb_close(db);
+
+  // If something is wrong, you might want to restore data from last backup
+  rocksdb_restore_options_t *restore_options = rocksdb_restore_options_create();
+  rocksdb_backup_engine_restore_db_from_latest_backup(be, DBPath, DBPath,
+                                                      restore_options, &err);
+  assert(!err);
+  rocksdb_restore_options_destroy(restore_options);
+
+  db = rocksdb_open(options, DBPath, &err);
+  assert(!err);
+
+  // cleanup
+  rocksdb_writeoptions_destroy(writeoptions);
+  rocksdb_readoptions_destroy(readoptions);
+  rocksdb_options_destroy(options);
+  rocksdb_backup_engine_close(be);
+  rocksdb_close(db);
+
+  return 0;
+}