update source to Ceph Pacific 16.2.2

[ceph.git] / ceph / src / jaegertracing / thrift / lib / d / src / thrift / transport / range.d

diff --git a/ceph/src/jaegertracing/thrift/lib/d/src/thrift/transport/range.d b/ceph/src/jaegertracing/thrift/lib/d/src/thrift/transport/range.d
new file mode 100644 (file)
index 0000000..761cea1
--- /dev/null
+++ b/ceph/src/jaegertracing/thrift/lib/d/src/thrift/transport/range.d
@@ -0,0 +1,147 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+/**
+ * Transports which operate on generic D ranges.
+ */
+module thrift.transport.range;
+
+import std.array : empty;
+import std.range;
+import std.traits : Unqual;
+import thrift.transport.base;
+
+/**
+ * Adapts an ubyte input range for reading via the TTransport interface.
+ *
+ * The case where R is a plain ubyte[] is reasonably optimized, so a possible
+ * use case for TInputRangeTransport would be to deserialize some data held in
+ * a memory buffer.
+ */
+final class TInputRangeTransport(R) if (
+  isInputRange!(Unqual!R) && is(ElementType!R : const(ubyte))
+) : TBaseTransport {
+  /**
+   * Constructs a new instance.
+   *
+   * Params:
+   *   data = The input range to use as data.
+   */
+  this(R data) {
+    data_ = data;
+  }
+
+  /**
+   * An input range transport is always open.
+   */
+  override bool isOpen() @property {
+    return true;
+  }
+
+  override bool peek() {
+    return !data_.empty;
+  }
+
+  /**
+   * Opening is a no-op() for an input range transport.
+   */
+  override void open() {}
+
+  /**
+   * Closing is a no-op() for a memory buffer.
+   */
+  override void close() {}
+
+  override size_t read(ubyte[] buf) {
+    auto data = data_.take(buf.length);
+    auto bytes = data.length;
+
+    static if (is(typeof(R.init[1 .. 2]) : const(ubyte)[])) {
+      // put() is currently unnecessarily slow if both ranges are sliceable.
+      buf[0 .. bytes] = data[];
+      data_ = data_[bytes .. $];
+    } else {
+      buf.put(data);
+    }
+
+    return bytes;
+  }
+
+  /**
+   * Shortcut version of readAll() for slicable ranges.
+   *
+   * Because readAll() is typically a very hot path during deserialization,
+   * using this over TBaseTransport.readAll() gives us a nice increase in
+   * speed due to the reduced amount of indirections.
+   */
+  override void readAll(ubyte[] buf) {
+    static if (is(typeof(R.init[1 .. 2]) : const(ubyte)[])) {
+      if (buf.length <= data_.length) {
+        buf[] = data_[0 .. buf.length];
+        data_ = data_[buf.length .. $];
+        return;
+      }
+    }
+    super.readAll(buf);
+  }
+
+  override const(ubyte)[] borrow(ubyte* buf, size_t len) {
+    static if (is(R : const(ubyte)[])) {
+      // Can only borrow if our data type is actually an ubyte array.
+      if (len <= data_.length) {
+        return data_;
+      }
+    }
+    return null;
+  }
+
+  override void consume(size_t len) {
+    static if (is(R : const(ubyte)[])) {
+      if (len > data_.length) {
+        throw new TTransportException("Invalid consume length",
+          TTransportException.Type.BAD_ARGS);
+      }
+      data_ = data_[len .. $];
+    } else {
+      super.consume(len);
+    }
+  }
+
+  /**
+   * Sets a new data range to use.
+   */
+  void reset(R data) {
+    data_ = data;
+  }
+
+private:
+  R data_;
+}
+
+/**
+ * TInputRangeTransport construction helper to avoid having to explicitly
+ * specify the argument type, i.e. to allow the constructor being called using
+ * IFTI (see $(LINK2 http://d.puremagic.com/issues/show_bug.cgi?id=6082, D
+ * Bugzilla enhancement requet 6082)).
+ */
+TInputRangeTransport!R tInputRangeTransport(R)(R data) if (
+  is (TInputRangeTransport!R)
+) {
+  return new TInputRangeTransport!R(data);
+}