Merge pull request #427 from haneefmubarak/c-examples

C example

examples/Makefile

@@ -2,7 +2,7 @@ include ../build_config.mk
 
 .PHONY: clean
 
-all: simple_example column_families_example compact_files_example
+all: simple_example column_families_example compact_files_example simple_example-c
 
 simple_example: simple_example.cc
 	$(CXX) $(CXXFLAGS) $@.cc -o$@ ../librocksdb.a -I../include -O2 -std=c++11 $(PLATFORM_LDFLAGS) $(PLATFORM_CXXFLAGS) $(EXEC_LDFLAGS)
@@ -13,5 +13,8 @@ column_families_example: column_families_example.cc
 compact_files_example: compact_files_example.cc
 	$(CXX) $(CXXFLAGS) $@.cc -o$@ ../librocksdb.a -I../include -O2 -std=c++11 $(PLATFORM_LDFLAGS) $(PLATFORM_CXXFLAGS) $(EXEC_LDFLAGS)
 
-clean: simple_example column_families_example compact_files_example
-	rm -rf ./simple_example ./column_families_example ./compact_files_example
+simple_example-c: simple_example.c
+	$(CXX) -xc -I../include simple_example.c -o$@ -L.. -lrocksdb -pthread -lsnappy -lbz2 -lz -lrt
+
+clean:
+	rm -rf ./simple_example ./column_families_example ./compact_files_example ./simple_example-c

examples/simple_example.c

@@ -0,0 +1,50 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <assert.h>
+
+#include "rocksdb/c.h"
+
+#include <unistd.h>	// sysconf() - get CPU count
+
+const char DBPath[] = "/tmp/rocksdb_simple_example";
+
+int main(int argc, char **argv) {
+	rocksdb_t *db;
+	rocksdb_options_t *options = rocksdb_options_create();
+	// Optimize RocksDB. This is the easiest way to
+	// get RocksDB to perform well
+	int cpus = sysconf(_SC_NPROCESSORS_ONLN);	// get # of online cores
+	rocksdb_options_increase_parallelism(options, 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);
+
+	// Put key-value
+	rocksdb_writeoptions_t *writeoptions = rocksdb_writeoptions_create();
+	const char key[] = "key";
+	char *value = "value";
+	rocksdb_put(db, writeoptions, key, strlen (key), value,	\
+			strlen (value), &err);
+	assert(!err);
+	// Get value
+	rocksdb_readoptions_t *readoptions = rocksdb_readoptions_create();
+	size_t len;
+	value = rocksdb_get(db, readoptions, key, strlen (key), &len, &err);
+	assert(!err);
+	assert(strcmp(value, "value") == 0);
+	free(value);
+
+	// cleanup
+	rocksdb_writeoptions_destroy(writeoptions);
+	rocksdb_readoptions_destroy(readoptions);
+	rocksdb_options_destroy(options);
+	rocksdb_close(db);
+
+	return 0;
+}