/*
- * 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.
* limitations under the License.
*/
-#ifndef FOLLY_IO_IOBUF_QUEUE_H
-#define FOLLY_IO_IOBUF_QUEUE_H
+#pragma once
-#include "folly/io/IOBuf.h"
+#include <folly/io/IOBuf.h>
#include <stdexcept>
#include <string>
/**
* Return a space to prepend bytes and the amount of headroom available.
*/
- std::pair<void*, uint32_t> headroom();
+ std::pair<void*, uint64_t> headroom();
/**
* Indicate that n bytes from the headroom have been used.
*/
- void markPrepended(uint32_t n);
+ void markPrepended(uint64_t n);
/**
* Prepend an existing range; throws std::overflow_error if not enough
* room.
*/
- void prepend(const void* buf, uint32_t n);
+ void prepend(const void* buf, uint64_t n);
/**
* Add a buffer or buffer chain to the end of this queue. The
* Copy a string to the end of this queue.
* The caller retains ownership of the source data.
*/
- void append(const std::string& buf) {
- append(buf.data(), buf.length());
+ void append(StringPiece sp) {
+ append(sp.data(), sp.size());
}
/**
* Importantly, this method may be used to wrap buffers larger than 4GB.
*/
void wrapBuffer(const void* buf, size_t len,
- uint32_t blockSize=(1U << 31)); // default block size: 2GB
+ uint64_t blockSize=(1U << 31)); // default block size: 2GB
/**
* Obtain a writable block of contiguous bytes at the end of this
* callback, tell the application how much of the buffer they've
* filled with data.
*/
- std::pair<void*,uint32_t> preallocate(
- uint32_t min, uint32_t newAllocationSize,
- uint32_t max = std::numeric_limits<uint32_t>::max()) {
+ std::pair<void*,uint64_t> preallocate(
+ uint64_t min, uint64_t newAllocationSize,
+ uint64_t max = std::numeric_limits<uint64_t>::max()) {
auto buf = tailBuf();
if (LIKELY(buf && buf->tailroom() >= min)) {
return std::make_pair(buf->writableTail(),
* invoke any other non-const methods on this IOBufQueue between
* the call to preallocate and the call to postallocate().
*/
- void postallocate(uint32_t n) {
+ void postallocate(uint64_t n) {
head_->prev()->append(n);
chainLength_ += n;
}
* Obtain a writable block of n contiguous bytes, allocating more space
* if necessary, and mark it as used. The caller can fill it later.
*/
- void* allocate(uint32_t n) {
+ void* allocate(uint64_t n) {
void* p = preallocate(n, n).first;
postallocate(n);
return p;
* @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
*/
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.
*/
*/
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&&);
+ 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*,uint32_t> preallocateSlow(
- uint32_t min, uint32_t newAllocationSize, uint32_t max);
+ 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 */
std::unique_ptr<folly::IOBuf> head_;
};
-} // folly
-
-#endif // FOLLY_IO_IOBUF_QUEUE_H
+} // namespace folly
projects / folly.git / blobdiff