X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;ds=sidebyside;f=folly%2Fio%2FIOBufQueue.h;h=c801920d34f793cd9e60608af254207652657564;hb=7ebe7c2a249de44209e8bcc453e1a70bafd4ed19;hp=cbc11376a993e731533c7c13e969963141079dbc;hpb=75c6adfae4a1842511e8b62150cc18ffb391efa7;p=folly.git

diff --git a/folly/io/IOBufQueue.h b/folly/io/IOBufQueue.h
index cbc11376..c801920d 100644
--- a/folly/io/IOBufQueue.h
+++ b/folly/io/IOBufQueue.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2014 Facebook, Inc.
+ * Copyright 2017 Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -14,8 +14,7 @@
  * limitations under the License.
  */
 
-#ifndef FOLLY_IO_IOBUF_QUEUE_H
-#define FOLLY_IO_IOBUF_QUEUE_H
+#pragma once
 
 #include <folly/io/IOBuf.h>
 
@@ -196,7 +195,17 @@ class IOBufQueue {
    * @throws std::underflow_error if n exceeds the number of bytes
    *         in the queue.
    */
-  std::unique_ptr<folly::IOBuf> split(size_t n);
+  std::unique_ptr<folly::IOBuf> split(size_t n) {
+    return split(n, true);
+  }
+
+  /**
+   * Similar to split, but will return the entire queue instead of throwing
+   * if n exceeds the number of bytes in the queue.
+   */
+  std::unique_ptr<folly::IOBuf> splitAtMost(size_t n) {
+    return split(n, false);
+  }
 
   /**
    * Similar to IOBuf::trimStart, but works on the whole queue.  Will
@@ -204,12 +213,24 @@ class IOBufQueue {
    */
   void trimStart(size_t amount);
 
+  /**
+   * Similar to trimStart, but will trim at most amount bytes and returns
+   * the number of bytes trimmed.
+   */
+  size_t trimStartAtMost(size_t amount);
+
   /**
    * Similar to IOBuf::trimEnd, but works on the whole queue.  Will
    * pop off buffers that have been completely trimmed.
    */
   void trimEnd(size_t amount);
 
+  /**
+   * Similar to trimEnd, but will trim at most amount bytes and returns
+   * the number of bytes trimmed.
+   */
+  size_t trimEndAtMost(size_t amount);
+
   /**
    * Transfer ownership of the queue's entire IOBuf chain to the caller.
    */
@@ -261,19 +282,33 @@ class IOBufQueue {
    */
   void clear();
 
+  /**
+   * Append the queue to a std::string. Non-destructive.
+   */
+  void appendToString(std::string& out) const;
+
+  /**
+   * Calls IOBuf::gather() on the head of the queue, if it exists.
+   */
+  void gather(uint64_t maxLength);
+
   /** Movable */
   IOBufQueue(IOBufQueue&&) noexcept;
   IOBufQueue& operator=(IOBufQueue&&);
 
  private:
   IOBuf* tailBuf() const {
-    if (UNLIKELY(!head_)) return nullptr;
+    if (UNLIKELY(!head_)) {
+      return nullptr;
+    }
     IOBuf* buf = head_->prev();
     return LIKELY(!buf->isSharedOne()) ? buf : nullptr;
   }
   std::pair<void*,uint64_t> preallocateSlow(
     uint64_t min, uint64_t newAllocationSize, uint64_t max);
 
+  std::unique_ptr<folly::IOBuf> split(size_t n, bool throwOnUnderflow);
+
   static const size_t kChainLengthNotCached = (size_t)-1;
   /** Not copyable */
   IOBufQueue(const IOBufQueue&) = delete;
@@ -289,6 +324,4 @@ class IOBufQueue {
   std::unique_ptr<folly::IOBuf> head_;
 };
 
-} // folly
-
-#endif // FOLLY_IO_IOBUF_QUEUE_H
+} // namespace folly