rocksdb_get2.patch

commit ae15c5220e084ec88db6f500e19f4df36d213aa8
Author: Evgenii Gurianov <whats.eternal@gmail.com>
Date:   Tue Dec 26 16:02:27 2017 +0300

    add rocksdb_get2

diff --git a/db/c.cc b/db/c.cc
index b00f4a9..4c85950 100644
--- a/db/c.cc
+++ b/db/c.cc
@@ -817,6 +817,32 @@ char* rocksdb_get(
   return result;
 }
 
+// return the length of the value
+// if buflen is less then the value length
+// than nothing is copied
+
+size_t rocksdb_get2(
+    rocksdb_t* db,
+    const rocksdb_readoptions_t* options,
+    const char* key, size_t keylen,
+    char* buf, size_t buflen,
+    char** errptr) {
+  size_t vallen = 0;
+  std::string tmp;
+  Status s = db->rep->Get(options->rep, Slice(key, keylen), &tmp);
+  if (s.ok()) {
+    vallen = tmp.size();
+    if (buflen > vallen) {
+      memcpy(buf, tmp.data(), sizeof(char) * tmp.size());
+    }
+  } else {
+    if (!s.IsNotFound()) {
+      SaveError(errptr, s);
+    }
+  }
+  return vallen;
+}
+
 char* rocksdb_get_cf(
     rocksdb_t* db,
     const rocksdb_readoptions_t* options,
diff --git a/include/rocksdb/c.h b/include/rocksdb/c.h
index b4ed9b4..474a6f4 100644
--- a/include/rocksdb/c.h
+++ b/include/rocksdb/c.h
@@ -262,6 +262,16 @@ extern ROCKSDB_LIBRARY_API char* rocksdb_get(
     rocksdb_t* db, const rocksdb_readoptions_t* options, const char* key,
     size_t keylen, size_t* vallen, char** errptr);
 
+/* Returns the length of the value
+   If buflen is less then the value length
+   than nothing is copied */
+extern ROCKSDB_LIBRARY_API size_t rocksdb_get2(
+    rocksdb_t* db,
+    const rocksdb_readoptions_t* options,
+    const char* key, size_t keylen,
+    char* buf, size_t buflen,
+    char** errptr);
+
 extern ROCKSDB_LIBRARY_API char* rocksdb_get_cf(
     rocksdb_t* db, const rocksdb_readoptions_t* options,
     rocksdb_column_family_handle_t* column_family, const char* key,