Squashed 'third_party/abseil/' changes from ddf8e52a2..384af0e91
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9f8b87b71 Add missing word 'library' in the 'status' description (#868)
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6df644c56 Include the status library into the main README. (#863)
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6b03bf543 fix build dll (#797)
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731852f10 Fix stacktrace on aarch64 architecture. Fixes #805 (#827)
2e5f2bcfd moved deleted functions to public for better compiler errors. (#828)
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e493d6acb fix compile fails with asan and -Wredundant-decls (#801)
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40fdb59d3 btree: fix sign-compare warnings (#800)
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7680a5f8e Added missing asserts for seq.index() < capacity_ and unified their usage based on has_element(). (#781)
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ea8a689cf fix build on P9 (#739)
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302b250e1 Disable pthread for standalone wasm build support (#721)
61d8bc057 Merge branch 'master' of https://github.com/abseil/abseil-cpp into master
4b5b25a28 cmake: remove unneeded enable_testing() cmd (#736)
63f2c695e cmake: flag conformance_testing as TESTONLY (#737)
d5269a8b6 Export of internal Abseil changes
23f1f9cf6 Typo in comment (#733)
259301a52 Fix CMake path for INSTALL_INCLUDEDIR (#723)
dc464c1dc Allow overriding Abseil IDE folder (#724)
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8faf20461 Exclude empty directories (#697)
2069dc796 Export of internal Abseil changes
4832bf6bf Added a BUILD file in root to expose license. (#695)
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3f347c462 Fix build on riscv32 (#675)
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f2bc9d11e Fix public target name of the random library (#684)
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b11574465 fix MSVC warning 4245: conversion signed => unsigned during initialization (#678)
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3f48ce1c4 init (#673)
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68494aae9 Fix CMake Threads dependency issue
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1a02b7a20 Use "-lrt" instead of the resolved find_library result when linking librt (#665)
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2946ac0de Use base_internal::AtomicHook instead of std::atomic (#661)
567bee2f7 Fix ABSL_RANDOM_RANDEN_COPTS setting on FreeBSD (#664)
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c01b9916e Add option to use an externally provided GoogleTest target (for usage of abseil as add_subdirectory target) (#647)
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132d791b4 bazel: Add missing load statements for cc_binary (#645)
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b92f35f65 Fix CompressedTuple move constructor on MSVC (#637)
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238b9a59c Skip the .exe suffix in the helpshort filter on Windows (#629)
417ea99cb UWP doesn't allow reading regkeys (#594)
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06f0e767d BuildBreak: UWP apps can't call GetModuleHandle (#596)
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0033c9ea9 Fix build on FreeBSD/powerpc (#616)
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2a5633fc0 Merge "Export of internal Abseil changes"
f9b3d6e49 Add RISCV support to GetProgramCounter() (#621)
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0232c87f2 Add missing ABSL_HAVE_VDSO_SUPPORT conditional (#622)
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36bcd9599 Fix pointer format specifier in documentation (#614)
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444277026 fix: Add support for more ARM processors detection (#608)
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7bd1935dc cmake: Fix x86_64 check on Windows for random copts (#518)
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85092b4b6 Fix Conan builds (#400)
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83880e3d8 Merge branch 'master' of https://github.com/abseil/abseil-cpp
8207907f4 Export of internal Abseil changes
39d68a422 docs: fix typo (#397)
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ecc0033b5 Always enable proper symbolize implementation on Windows (#257)
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e9f9000c7 Fix ABSL_WAITER_MODE detection for mingw (#342)
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882b3501a Fix spelling errors (#384)
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Change-Id: I59864a0053f6e03d88cc9d5e2a92757039a05484
git-subtree-dir: third_party/abseil
git-subtree-split: 384af0e9141283172e2bff3210dae79fb7130d9c
diff --git a/absl/strings/cord.h b/absl/strings/cord.h
new file mode 100644
index 0000000..7136f03
--- /dev/null
+++ b/absl/strings/cord.h
@@ -0,0 +1,1322 @@
+// Copyright 2020 The Abseil Authors.
+//
+// Licensed 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
+//
+// https://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.
+//
+// -----------------------------------------------------------------------------
+// File: cord.h
+// -----------------------------------------------------------------------------
+//
+// This file defines the `absl::Cord` data structure and operations on that data
+// structure. A Cord is a string-like sequence of characters optimized for
+// specific use cases. Unlike a `std::string`, which stores an array of
+// contiguous characters, Cord data is stored in a structure consisting of
+// separate, reference-counted "chunks." (Currently, this implementation is a
+// tree structure, though that implementation may change.)
+//
+// Because a Cord consists of these chunks, data can be added to or removed from
+// a Cord during its lifetime. Chunks may also be shared between Cords. Unlike a
+// `std::string`, a Cord can therefore accomodate data that changes over its
+// lifetime, though it's not quite "mutable"; it can change only in the
+// attachment, detachment, or rearrangement of chunks of its constituent data.
+//
+// A Cord provides some benefit over `std::string` under the following (albeit
+// narrow) circumstances:
+//
+// * Cord data is designed to grow and shrink over a Cord's lifetime. Cord
+// provides efficient insertions and deletions at the start and end of the
+// character sequences, avoiding copies in those cases. Static data should
+// generally be stored as strings.
+// * External memory consisting of string-like data can be directly added to
+// a Cord without requiring copies or allocations.
+// * Cord data may be shared and copied cheaply. Cord provides a copy-on-write
+// implementation and cheap sub-Cord operations. Copying a Cord is an O(1)
+// operation.
+//
+// As a consequence to the above, Cord data is generally large. Small data
+// should generally use strings, as construction of a Cord requires some
+// overhead. Small Cords (<= 15 bytes) are represented inline, but most small
+// Cords are expected to grow over their lifetimes.
+//
+// Note that because a Cord is made up of separate chunked data, random access
+// to character data within a Cord is slower than within a `std::string`.
+//
+// Thread Safety
+//
+// Cord has the same thread-safety properties as many other types like
+// std::string, std::vector<>, int, etc -- it is thread-compatible. In
+// particular, if threads do not call non-const methods, then it is safe to call
+// const methods without synchronization. Copying a Cord produces a new instance
+// that can be used concurrently with the original in arbitrary ways.
+
+#ifndef ABSL_STRINGS_CORD_H_
+#define ABSL_STRINGS_CORD_H_
+
+#include <algorithm>
+#include <cstddef>
+#include <cstdint>
+#include <cstring>
+#include <iosfwd>
+#include <iterator>
+#include <string>
+#include <type_traits>
+
+#include "absl/base/internal/endian.h"
+#include "absl/base/internal/per_thread_tls.h"
+#include "absl/base/macros.h"
+#include "absl/base/port.h"
+#include "absl/container/inlined_vector.h"
+#include "absl/functional/function_ref.h"
+#include "absl/meta/type_traits.h"
+#include "absl/strings/internal/cord_internal.h"
+#include "absl/strings/internal/resize_uninitialized.h"
+#include "absl/strings/internal/string_constant.h"
+#include "absl/strings/string_view.h"
+#include "absl/types/optional.h"
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+class Cord;
+class CordTestPeer;
+template <typename Releaser>
+Cord MakeCordFromExternal(absl::string_view, Releaser&&);
+void CopyCordToString(const Cord& src, std::string* dst);
+
+// Cord
+//
+// A Cord is a sequence of characters, designed to be more efficient than a
+// `std::string` in certain circumstances: namely, large string data that needs
+// to change over its lifetime or shared, especially when such data is shared
+// across API boundaries.
+//
+// A Cord stores its character data in a structure that allows efficient prepend
+// and append operations. This makes a Cord useful for large string data sent
+// over in a wire format that may need to be prepended or appended at some point
+// during the data exchange (e.g. HTTP, protocol buffers). For example, a
+// Cord is useful for storing an HTTP request, and prepending an HTTP header to
+// such a request.
+//
+// Cords should not be used for storing general string data, however. They
+// require overhead to construct and are slower than strings for random access.
+//
+// The Cord API provides the following common API operations:
+//
+// * Create or assign Cords out of existing string data, memory, or other Cords
+// * Append and prepend data to an existing Cord
+// * Create new Sub-Cords from existing Cord data
+// * Swap Cord data and compare Cord equality
+// * Write out Cord data by constructing a `std::string`
+//
+// Additionally, the API provides iterator utilities to iterate through Cord
+// data via chunks or character bytes.
+//
+class Cord {
+ private:
+ template <typename T>
+ using EnableIfString =
+ absl::enable_if_t<std::is_same<T, std::string>::value, int>;
+
+ public:
+ // Cord::Cord() Constructors.
+
+ // Creates an empty Cord.
+ constexpr Cord() noexcept;
+
+ // Creates a Cord from an existing Cord. Cord is copyable and efficiently
+ // movable. The moved-from state is valid but unspecified.
+ Cord(const Cord& src);
+ Cord(Cord&& src) noexcept;
+ Cord& operator=(const Cord& x);
+ Cord& operator=(Cord&& x) noexcept;
+
+ // Creates a Cord from a `src` string. This constructor is marked explicit to
+ // prevent implicit Cord constructions from arguments convertible to an
+ // `absl::string_view`.
+ explicit Cord(absl::string_view src);
+ Cord& operator=(absl::string_view src);
+
+ // Creates a Cord from a `std::string&&` rvalue. These constructors are
+ // templated to avoid ambiguities for types that are convertible to both
+ // `absl::string_view` and `std::string`, such as `const char*`.
+ template <typename T, EnableIfString<T> = 0>
+ explicit Cord(T&& src);
+ template <typename T, EnableIfString<T> = 0>
+ Cord& operator=(T&& src);
+
+ // Cord::~Cord()
+ //
+ // Destructs the Cord.
+ ~Cord() {
+ if (contents_.is_tree()) DestroyCordSlow();
+ }
+
+ // MakeCordFromExternal()
+ //
+ // Creates a Cord that takes ownership of external string memory. The
+ // contents of `data` are not copied to the Cord; instead, the external
+ // memory is added to the Cord and reference-counted. This data may not be
+ // changed for the life of the Cord, though it may be prepended or appended
+ // to.
+ //
+ // `MakeCordFromExternal()` takes a callable "releaser" that is invoked when
+ // the reference count for `data` reaches zero. As noted above, this data must
+ // remain live until the releaser is invoked. The callable releaser also must:
+ //
+ // * be move constructible
+ // * support `void operator()(absl::string_view) const` or `void operator()`
+ //
+ // Example:
+ //
+ // Cord MakeCord(BlockPool* pool) {
+ // Block* block = pool->NewBlock();
+ // FillBlock(block);
+ // return absl::MakeCordFromExternal(
+ // block->ToStringView(),
+ // [pool, block](absl::string_view v) {
+ // pool->FreeBlock(block, v);
+ // });
+ // }
+ //
+ // WARNING: Because a Cord can be reference-counted, it's likely a bug if your
+ // releaser doesn't do anything. For example, consider the following:
+ //
+ // void Foo(const char* buffer, int len) {
+ // auto c = absl::MakeCordFromExternal(absl::string_view(buffer, len),
+ // [](absl::string_view) {});
+ //
+ // // BUG: If Bar() copies its cord for any reason, including keeping a
+ // // substring of it, the lifetime of buffer might be extended beyond
+ // // when Foo() returns.
+ // Bar(c);
+ // }
+ template <typename Releaser>
+ friend Cord MakeCordFromExternal(absl::string_view data, Releaser&& releaser);
+
+ // Cord::Clear()
+ //
+ // Releases the Cord data. Any nodes that share data with other Cords, if
+ // applicable, will have their reference counts reduced by 1.
+ void Clear();
+
+ // Cord::Append()
+ //
+ // Appends data to the Cord, which may come from another Cord or other string
+ // data.
+ void Append(const Cord& src);
+ void Append(Cord&& src);
+ void Append(absl::string_view src);
+ template <typename T, EnableIfString<T> = 0>
+ void Append(T&& src);
+
+ // Cord::Prepend()
+ //
+ // Prepends data to the Cord, which may come from another Cord or other string
+ // data.
+ void Prepend(const Cord& src);
+ void Prepend(absl::string_view src);
+ template <typename T, EnableIfString<T> = 0>
+ void Prepend(T&& src);
+
+ // Cord::RemovePrefix()
+ //
+ // Removes the first `n` bytes of a Cord.
+ void RemovePrefix(size_t n);
+ void RemoveSuffix(size_t n);
+
+ // Cord::Subcord()
+ //
+ // Returns a new Cord representing the subrange [pos, pos + new_size) of
+ // *this. If pos >= size(), the result is empty(). If
+ // (pos + new_size) >= size(), the result is the subrange [pos, size()).
+ Cord Subcord(size_t pos, size_t new_size) const;
+
+ // Cord::swap()
+ //
+ // Swaps the contents of the Cord with `other`.
+ void swap(Cord& other) noexcept;
+
+ // swap()
+ //
+ // Swaps the contents of two Cords.
+ friend void swap(Cord& x, Cord& y) noexcept {
+ x.swap(y);
+ }
+
+ // Cord::size()
+ //
+ // Returns the size of the Cord.
+ size_t size() const;
+
+ // Cord::empty()
+ //
+ // Determines whether the given Cord is empty, returning `true` is so.
+ bool empty() const;
+
+ // Cord::EstimatedMemoryUsage()
+ //
+ // Returns the *approximate* number of bytes held in full or in part by this
+ // Cord (which may not remain the same between invocations). Note that Cords
+ // that share memory could each be "charged" independently for the same shared
+ // memory.
+ size_t EstimatedMemoryUsage() const;
+
+ // Cord::Compare()
+ //
+ // Compares 'this' Cord with rhs. This function and its relatives treat Cords
+ // as sequences of unsigned bytes. The comparison is a straightforward
+ // lexicographic comparison. `Cord::Compare()` returns values as follows:
+ //
+ // -1 'this' Cord is smaller
+ // 0 two Cords are equal
+ // 1 'this' Cord is larger
+ int Compare(absl::string_view rhs) const;
+ int Compare(const Cord& rhs) const;
+
+ // Cord::StartsWith()
+ //
+ // Determines whether the Cord starts with the passed string data `rhs`.
+ bool StartsWith(const Cord& rhs) const;
+ bool StartsWith(absl::string_view rhs) const;
+
+ // Cord::EndsWidth()
+ //
+ // Determines whether the Cord ends with the passed string data `rhs`.
+ bool EndsWith(absl::string_view rhs) const;
+ bool EndsWith(const Cord& rhs) const;
+
+ // Cord::operator std::string()
+ //
+ // Converts a Cord into a `std::string()`. This operator is marked explicit to
+ // prevent unintended Cord usage in functions that take a string.
+ explicit operator std::string() const;
+
+ // CopyCordToString()
+ //
+ // Copies the contents of a `src` Cord into a `*dst` string.
+ //
+ // This function optimizes the case of reusing the destination string since it
+ // can reuse previously allocated capacity. However, this function does not
+ // guarantee that pointers previously returned by `dst->data()` remain valid
+ // even if `*dst` had enough capacity to hold `src`. If `*dst` is a new
+ // object, prefer to simply use the conversion operator to `std::string`.
+ friend void CopyCordToString(const Cord& src, std::string* dst);
+
+ class CharIterator;
+
+ //----------------------------------------------------------------------------
+ // Cord::ChunkIterator
+ //----------------------------------------------------------------------------
+ //
+ // A `Cord::ChunkIterator` allows iteration over the constituent chunks of its
+ // Cord. Such iteration allows you to perform non-const operatons on the data
+ // of a Cord without modifying it.
+ //
+ // Generally, you do not instantiate a `Cord::ChunkIterator` directly;
+ // instead, you create one implicitly through use of the `Cord::Chunks()`
+ // member function.
+ //
+ // The `Cord::ChunkIterator` has the following properties:
+ //
+ // * The iterator is invalidated after any non-const operation on the
+ // Cord object over which it iterates.
+ // * The `string_view` returned by dereferencing a valid, non-`end()`
+ // iterator is guaranteed to be non-empty.
+ // * Two `ChunkIterator` objects can be compared equal if and only if they
+ // remain valid and iterate over the same Cord.
+ // * The iterator in this case is a proxy iterator; the `string_view`
+ // returned by the iterator does not live inside the Cord, and its
+ // lifetime is limited to the lifetime of the iterator itself. To help
+ // prevent lifetime issues, `ChunkIterator::reference` is not a true
+ // reference type and is equivalent to `value_type`.
+ // * The iterator keeps state that can grow for Cords that contain many
+ // nodes and are imbalanced due to sharing. Prefer to pass this type by
+ // const reference instead of by value.
+ class ChunkIterator {
+ public:
+ using iterator_category = std::input_iterator_tag;
+ using value_type = absl::string_view;
+ using difference_type = ptrdiff_t;
+ using pointer = const value_type*;
+ using reference = value_type;
+
+ ChunkIterator() = default;
+
+ ChunkIterator& operator++();
+ ChunkIterator operator++(int);
+ bool operator==(const ChunkIterator& other) const;
+ bool operator!=(const ChunkIterator& other) const;
+ reference operator*() const;
+ pointer operator->() const;
+
+ friend class Cord;
+ friend class CharIterator;
+
+ private:
+ // Stack of right children of concat nodes that we have to visit.
+ // Keep this at the end of the structure to avoid cache-thrashing.
+ // TODO(jgm): Benchmark to see if there's a more optimal value than 47 for
+ // the inlined vector size (47 exists for backward compatibility).
+ using Stack = absl::InlinedVector<absl::cord_internal::CordRep*, 47>;
+
+ // Constructs a `begin()` iterator from `cord`.
+ explicit ChunkIterator(const Cord* cord);
+
+ // Removes `n` bytes from `current_chunk_`. Expects `n` to be smaller than
+ // `current_chunk_.size()`.
+ void RemoveChunkPrefix(size_t n);
+ Cord AdvanceAndReadBytes(size_t n);
+ void AdvanceBytes(size_t n);
+
+ // Stack specific operator++
+ ChunkIterator& AdvanceStack();
+
+ // Iterates `n` bytes, where `n` is expected to be greater than or equal to
+ // `current_chunk_.size()`.
+ void AdvanceBytesSlowPath(size_t n);
+
+ // A view into bytes of the current `CordRep`. It may only be a view to a
+ // suffix of bytes if this is being used by `CharIterator`.
+ absl::string_view current_chunk_;
+ // The current leaf, or `nullptr` if the iterator points to short data.
+ // If the current chunk is a substring node, current_leaf_ points to the
+ // underlying flat or external node.
+ absl::cord_internal::CordRep* current_leaf_ = nullptr;
+ // The number of bytes left in the `Cord` over which we are iterating.
+ size_t bytes_remaining_ = 0;
+ // See 'Stack' alias definition.
+ Stack stack_of_right_children_;
+ };
+
+ // Cord::ChunkIterator::chunk_begin()
+ //
+ // Returns an iterator to the first chunk of the `Cord`.
+ //
+ // Generally, prefer using `Cord::Chunks()` within a range-based for loop for
+ // iterating over the chunks of a Cord. This method may be useful for getting
+ // a `ChunkIterator` where range-based for-loops are not useful.
+ //
+ // Example:
+ //
+ // absl::Cord::ChunkIterator FindAsChunk(const absl::Cord& c,
+ // absl::string_view s) {
+ // return std::find(c.chunk_begin(), c.chunk_end(), s);
+ // }
+ ChunkIterator chunk_begin() const;
+
+ // Cord::ChunkItertator::chunk_end()
+ //
+ // Returns an iterator one increment past the last chunk of the `Cord`.
+ //
+ // Generally, prefer using `Cord::Chunks()` within a range-based for loop for
+ // iterating over the chunks of a Cord. This method may be useful for getting
+ // a `ChunkIterator` where range-based for-loops may not be available.
+ ChunkIterator chunk_end() const;
+
+ //----------------------------------------------------------------------------
+ // Cord::ChunkIterator::ChunkRange
+ //----------------------------------------------------------------------------
+ //
+ // `ChunkRange` is a helper class for iterating over the chunks of the `Cord`,
+ // producing an iterator which can be used within a range-based for loop.
+ // Construction of a `ChunkRange` will return an iterator pointing to the
+ // first chunk of the Cord. Generally, do not construct a `ChunkRange`
+ // directly; instead, prefer to use the `Cord::Chunks()` method.
+ //
+ // Implementation note: `ChunkRange` is simply a convenience wrapper over
+ // `Cord::chunk_begin()` and `Cord::chunk_end()`.
+ class ChunkRange {
+ public:
+ explicit ChunkRange(const Cord* cord) : cord_(cord) {}
+
+ ChunkIterator begin() const;
+ ChunkIterator end() const;
+
+ private:
+ const Cord* cord_;
+ };
+
+ // Cord::Chunks()
+ //
+ // Returns a `Cord::ChunkIterator::ChunkRange` for iterating over the chunks
+ // of a `Cord` with a range-based for-loop. For most iteration tasks on a
+ // Cord, use `Cord::Chunks()` to retrieve this iterator.
+ //
+ // Example:
+ //
+ // void ProcessChunks(const Cord& cord) {
+ // for (absl::string_view chunk : cord.Chunks()) { ... }
+ // }
+ //
+ // Note that the ordinary caveats of temporary lifetime extension apply:
+ //
+ // void Process() {
+ // for (absl::string_view chunk : CordFactory().Chunks()) {
+ // // The temporary Cord returned by CordFactory has been destroyed!
+ // }
+ // }
+ ChunkRange Chunks() const;
+
+ //----------------------------------------------------------------------------
+ // Cord::CharIterator
+ //----------------------------------------------------------------------------
+ //
+ // A `Cord::CharIterator` allows iteration over the constituent characters of
+ // a `Cord`.
+ //
+ // Generally, you do not instantiate a `Cord::CharIterator` directly; instead,
+ // you create one implicitly through use of the `Cord::Chars()` member
+ // function.
+ //
+ // A `Cord::CharIterator` has the following properties:
+ //
+ // * The iterator is invalidated after any non-const operation on the
+ // Cord object over which it iterates.
+ // * Two `CharIterator` objects can be compared equal if and only if they
+ // remain valid and iterate over the same Cord.
+ // * The iterator keeps state that can grow for Cords that contain many
+ // nodes and are imbalanced due to sharing. Prefer to pass this type by
+ // const reference instead of by value.
+ // * This type cannot act as a forward iterator because a `Cord` can reuse
+ // sections of memory. This fact violates the requirement for forward
+ // iterators to compare equal if dereferencing them returns the same
+ // object.
+ class CharIterator {
+ public:
+ using iterator_category = std::input_iterator_tag;
+ using value_type = char;
+ using difference_type = ptrdiff_t;
+ using pointer = const char*;
+ using reference = const char&;
+
+ CharIterator() = default;
+
+ CharIterator& operator++();
+ CharIterator operator++(int);
+ bool operator==(const CharIterator& other) const;
+ bool operator!=(const CharIterator& other) const;
+ reference operator*() const;
+ pointer operator->() const;
+
+ friend Cord;
+
+ private:
+ explicit CharIterator(const Cord* cord) : chunk_iterator_(cord) {}
+
+ ChunkIterator chunk_iterator_;
+ };
+
+ // Cord::CharIterator::AdvanceAndRead()
+ //
+ // Advances the `Cord::CharIterator` by `n_bytes` and returns the bytes
+ // advanced as a separate `Cord`. `n_bytes` must be less than or equal to the
+ // number of bytes within the Cord; otherwise, behavior is undefined. It is
+ // valid to pass `char_end()` and `0`.
+ static Cord AdvanceAndRead(CharIterator* it, size_t n_bytes);
+
+ // Cord::CharIterator::Advance()
+ //
+ // Advances the `Cord::CharIterator` by `n_bytes`. `n_bytes` must be less than
+ // or equal to the number of bytes remaining within the Cord; otherwise,
+ // behavior is undefined. It is valid to pass `char_end()` and `0`.
+ static void Advance(CharIterator* it, size_t n_bytes);
+
+ // Cord::CharIterator::ChunkRemaining()
+ //
+ // Returns the longest contiguous view starting at the iterator's position.
+ //
+ // `it` must be dereferenceable.
+ static absl::string_view ChunkRemaining(const CharIterator& it);
+
+ // Cord::CharIterator::char_begin()
+ //
+ // Returns an iterator to the first character of the `Cord`.
+ //
+ // Generally, prefer using `Cord::Chars()` within a range-based for loop for
+ // iterating over the chunks of a Cord. This method may be useful for getting
+ // a `CharIterator` where range-based for-loops may not be available.
+ CharIterator char_begin() const;
+
+ // Cord::CharIterator::char_end()
+ //
+ // Returns an iterator to one past the last character of the `Cord`.
+ //
+ // Generally, prefer using `Cord::Chars()` within a range-based for loop for
+ // iterating over the chunks of a Cord. This method may be useful for getting
+ // a `CharIterator` where range-based for-loops are not useful.
+ CharIterator char_end() const;
+
+ // Cord::CharIterator::CharRange
+ //
+ // `CharRange` is a helper class for iterating over the characters of a
+ // producing an iterator which can be used within a range-based for loop.
+ // Construction of a `CharRange` will return an iterator pointing to the first
+ // character of the Cord. Generally, do not construct a `CharRange` directly;
+ // instead, prefer to use the `Cord::Chars()` method show below.
+ //
+ // Implementation note: `CharRange` is simply a convenience wrapper over
+ // `Cord::char_begin()` and `Cord::char_end()`.
+ class CharRange {
+ public:
+ explicit CharRange(const Cord* cord) : cord_(cord) {}
+
+ CharIterator begin() const;
+ CharIterator end() const;
+
+ private:
+ const Cord* cord_;
+ };
+
+ // Cord::CharIterator::Chars()
+ //
+ // Returns a `Cord::CharIterator` for iterating over the characters of a
+ // `Cord` with a range-based for-loop. For most character-based iteration
+ // tasks on a Cord, use `Cord::Chars()` to retrieve this iterator.
+ //
+ // Example:
+ //
+ // void ProcessCord(const Cord& cord) {
+ // for (char c : cord.Chars()) { ... }
+ // }
+ //
+ // Note that the ordinary caveats of temporary lifetime extension apply:
+ //
+ // void Process() {
+ // for (char c : CordFactory().Chars()) {
+ // // The temporary Cord returned by CordFactory has been destroyed!
+ // }
+ // }
+ CharRange Chars() const;
+
+ // Cord::operator[]
+ //
+ // Gets the "i"th character of the Cord and returns it, provided that
+ // 0 <= i < Cord.size().
+ //
+ // NOTE: This routine is reasonably efficient. It is roughly
+ // logarithmic based on the number of chunks that make up the cord. Still,
+ // if you need to iterate over the contents of a cord, you should
+ // use a CharIterator/ChunkIterator rather than call operator[] or Get()
+ // repeatedly in a loop.
+ char operator[](size_t i) const;
+
+ // Cord::TryFlat()
+ //
+ // If this cord's representation is a single flat array, returns a
+ // string_view referencing that array. Otherwise returns nullopt.
+ absl::optional<absl::string_view> TryFlat() const;
+
+ // Cord::Flatten()
+ //
+ // Flattens the cord into a single array and returns a view of the data.
+ //
+ // If the cord was already flat, the contents are not modified.
+ absl::string_view Flatten();
+
+ // Supports absl::Cord as a sink object for absl::Format().
+ friend void AbslFormatFlush(absl::Cord* cord, absl::string_view part) {
+ cord->Append(part);
+ }
+
+ template <typename H>
+ friend H AbslHashValue(H hash_state, const absl::Cord& c) {
+ absl::optional<absl::string_view> maybe_flat = c.TryFlat();
+ if (maybe_flat.has_value()) {
+ return H::combine(std::move(hash_state), *maybe_flat);
+ }
+ return c.HashFragmented(std::move(hash_state));
+ }
+
+ // Create a Cord with the contents of StringConstant<T>::value.
+ // No allocations will be done and no data will be copied.
+ // This is an INTERNAL API and subject to change or removal. This API can only
+ // be used by spelling absl::strings_internal::MakeStringConstant, which is
+ // also an internal API.
+ template <typename T>
+ explicit constexpr Cord(strings_internal::StringConstant<T>);
+
+ private:
+ friend class CordTestPeer;
+ friend bool operator==(const Cord& lhs, const Cord& rhs);
+ friend bool operator==(const Cord& lhs, absl::string_view rhs);
+
+ // Calls the provided function once for each cord chunk, in order. Unlike
+ // Chunks(), this API will not allocate memory.
+ void ForEachChunk(absl::FunctionRef<void(absl::string_view)>) const;
+
+ // Allocates new contiguous storage for the contents of the cord. This is
+ // called by Flatten() when the cord was not already flat.
+ absl::string_view FlattenSlowPath();
+
+ // Actual cord contents are hidden inside the following simple
+ // class so that we can isolate the bulk of cord.cc from changes
+ // to the representation.
+ //
+ // InlineRep holds either a tree pointer, or an array of kMaxInline bytes.
+ class InlineRep {
+ public:
+ static constexpr unsigned char kMaxInline = cord_internal::kMaxInline;
+ static_assert(kMaxInline >= sizeof(absl::cord_internal::CordRep*), "");
+ static constexpr unsigned char kTreeFlag = cord_internal::kTreeFlag;
+ static constexpr unsigned char kProfiledFlag = cord_internal::kProfiledFlag;
+
+ constexpr InlineRep() : data_() {}
+ InlineRep(const InlineRep& src);
+ InlineRep(InlineRep&& src);
+ InlineRep& operator=(const InlineRep& src);
+ InlineRep& operator=(InlineRep&& src) noexcept;
+
+ explicit constexpr InlineRep(cord_internal::InlineData data);
+
+ void Swap(InlineRep* rhs);
+ bool empty() const;
+ size_t size() const;
+ const char* data() const; // Returns nullptr if holding pointer
+ void set_data(const char* data, size_t n,
+ bool nullify_tail); // Discards pointer, if any
+ char* set_data(size_t n); // Write data to the result
+ // Returns nullptr if holding bytes
+ absl::cord_internal::CordRep* tree() const;
+ // Discards old pointer, if any
+ void set_tree(absl::cord_internal::CordRep* rep);
+ // Replaces a tree with a new root. This is faster than set_tree, but it
+ // should only be used when it's clear that the old rep was a tree.
+ void replace_tree(absl::cord_internal::CordRep* rep);
+ // Returns non-null iff was holding a pointer
+ absl::cord_internal::CordRep* clear();
+ // Converts to pointer if necessary.
+ absl::cord_internal::CordRep* force_tree(size_t extra_hint);
+ void reduce_size(size_t n); // REQUIRES: holding data
+ void remove_prefix(size_t n); // REQUIRES: holding data
+ void AppendArray(const char* src_data, size_t src_size);
+ absl::string_view FindFlatStartPiece() const;
+ void AppendTree(absl::cord_internal::CordRep* tree);
+ void PrependTree(absl::cord_internal::CordRep* tree);
+ void GetAppendRegion(char** region, size_t* size, size_t max_length);
+ void GetAppendRegion(char** region, size_t* size);
+ bool IsSame(const InlineRep& other) const {
+ return memcmp(&data_, &other.data_, sizeof(data_)) == 0;
+ }
+ int BitwiseCompare(const InlineRep& other) const {
+ uint64_t x, y;
+ // Use memcpy to avoid aliasing issues.
+ memcpy(&x, &data_, sizeof(x));
+ memcpy(&y, &other.data_, sizeof(y));
+ if (x == y) {
+ memcpy(&x, reinterpret_cast<const char*>(&data_) + 8, sizeof(x));
+ memcpy(&y, reinterpret_cast<const char*>(&other.data_) + 8, sizeof(y));
+ if (x == y) return 0;
+ }
+ return absl::big_endian::FromHost64(x) < absl::big_endian::FromHost64(y)
+ ? -1
+ : 1;
+ }
+ void CopyTo(std::string* dst) const {
+ // memcpy is much faster when operating on a known size. On most supported
+ // platforms, the small string optimization is large enough that resizing
+ // to 15 bytes does not cause a memory allocation.
+ absl::strings_internal::STLStringResizeUninitialized(dst,
+ sizeof(data_) - 1);
+ memcpy(&(*dst)[0], &data_, sizeof(data_) - 1);
+ // erase is faster than resize because the logic for memory allocation is
+ // not needed.
+ dst->erase(tagged_size());
+ }
+
+ // Copies the inline contents into `dst`. Assumes the cord is not empty.
+ void CopyToArray(char* dst) const;
+
+ bool is_tree() const { return tagged_size() > kMaxInline; }
+
+ private:
+ friend class Cord;
+
+ void AssignSlow(const InlineRep& src);
+ // Unrefs the tree, stops profiling, and zeroes the contents
+ void ClearSlow();
+
+ void ResetToEmpty() { data_ = {}; }
+
+ // This uses reinterpret_cast instead of the union to avoid accessing the
+ // inactive union element. The tagged size is not a common prefix.
+ void set_tagged_size(char new_tag) {
+ reinterpret_cast<char*>(&data_)[kMaxInline] = new_tag;
+ }
+ char tagged_size() const {
+ return reinterpret_cast<const char*>(&data_)[kMaxInline];
+ }
+
+ cord_internal::InlineData data_;
+ };
+ InlineRep contents_;
+
+ // Helper for MemoryUsage().
+ static size_t MemoryUsageAux(const absl::cord_internal::CordRep* rep);
+
+ // Helper for GetFlat() and TryFlat().
+ static bool GetFlatAux(absl::cord_internal::CordRep* rep,
+ absl::string_view* fragment);
+
+ // Helper for ForEachChunk().
+ static void ForEachChunkAux(
+ absl::cord_internal::CordRep* rep,
+ absl::FunctionRef<void(absl::string_view)> callback);
+
+ // The destructor for non-empty Cords.
+ void DestroyCordSlow();
+
+ // Out-of-line implementation of slower parts of logic.
+ void CopyToArraySlowPath(char* dst) const;
+ int CompareSlowPath(absl::string_view rhs, size_t compared_size,
+ size_t size_to_compare) const;
+ int CompareSlowPath(const Cord& rhs, size_t compared_size,
+ size_t size_to_compare) const;
+ bool EqualsImpl(absl::string_view rhs, size_t size_to_compare) const;
+ bool EqualsImpl(const Cord& rhs, size_t size_to_compare) const;
+ int CompareImpl(const Cord& rhs) const;
+
+ template <typename ResultType, typename RHS>
+ friend ResultType GenericCompare(const Cord& lhs, const RHS& rhs,
+ size_t size_to_compare);
+ static absl::string_view GetFirstChunk(const Cord& c);
+ static absl::string_view GetFirstChunk(absl::string_view sv);
+
+ // Returns a new reference to contents_.tree(), or steals an existing
+ // reference if called on an rvalue.
+ absl::cord_internal::CordRep* TakeRep() const&;
+ absl::cord_internal::CordRep* TakeRep() &&;
+
+ // Helper for Append().
+ template <typename C>
+ void AppendImpl(C&& src);
+
+ // Helper for AbslHashValue().
+ template <typename H>
+ H HashFragmented(H hash_state) const {
+ typename H::AbslInternalPiecewiseCombiner combiner;
+ ForEachChunk([&combiner, &hash_state](absl::string_view chunk) {
+ hash_state = combiner.add_buffer(std::move(hash_state), chunk.data(),
+ chunk.size());
+ });
+ return H::combine(combiner.finalize(std::move(hash_state)), size());
+ }
+};
+
+ABSL_NAMESPACE_END
+} // namespace absl
+
+namespace absl {
+ABSL_NAMESPACE_BEGIN
+
+// allow a Cord to be logged
+extern std::ostream& operator<<(std::ostream& out, const Cord& cord);
+
+// ------------------------------------------------------------------
+// Internal details follow. Clients should ignore.
+
+namespace cord_internal {
+
+// Fast implementation of memmove for up to 15 bytes. This implementation is
+// safe for overlapping regions. If nullify_tail is true, the destination is
+// padded with '\0' up to 16 bytes.
+inline void SmallMemmove(char* dst, const char* src, size_t n,
+ bool nullify_tail = false) {
+ if (n >= 8) {
+ assert(n <= 16);
+ uint64_t buf1;
+ uint64_t buf2;
+ memcpy(&buf1, src, 8);
+ memcpy(&buf2, src + n - 8, 8);
+ if (nullify_tail) {
+ memset(dst + 8, 0, 8);
+ }
+ memcpy(dst, &buf1, 8);
+ memcpy(dst + n - 8, &buf2, 8);
+ } else if (n >= 4) {
+ uint32_t buf1;
+ uint32_t buf2;
+ memcpy(&buf1, src, 4);
+ memcpy(&buf2, src + n - 4, 4);
+ if (nullify_tail) {
+ memset(dst + 4, 0, 4);
+ memset(dst + 8, 0, 8);
+ }
+ memcpy(dst, &buf1, 4);
+ memcpy(dst + n - 4, &buf2, 4);
+ } else {
+ if (n != 0) {
+ dst[0] = src[0];
+ dst[n / 2] = src[n / 2];
+ dst[n - 1] = src[n - 1];
+ }
+ if (nullify_tail) {
+ memset(dst + 8, 0, 8);
+ memset(dst + n, 0, 8);
+ }
+ }
+}
+
+// Does non-template-specific `CordRepExternal` initialization.
+// Expects `data` to be non-empty.
+void InitializeCordRepExternal(absl::string_view data, CordRepExternal* rep);
+
+// Creates a new `CordRep` that owns `data` and `releaser` and returns a pointer
+// to it, or `nullptr` if `data` was empty.
+template <typename Releaser>
+// NOLINTNEXTLINE - suppress clang-tidy raw pointer return.
+CordRep* NewExternalRep(absl::string_view data, Releaser&& releaser) {
+ using ReleaserType = absl::decay_t<Releaser>;
+ if (data.empty()) {
+ // Never create empty external nodes.
+ InvokeReleaser(Rank0{}, ReleaserType(std::forward<Releaser>(releaser)),
+ data);
+ return nullptr;
+ }
+
+ CordRepExternal* rep = new CordRepExternalImpl<ReleaserType>(
+ std::forward<Releaser>(releaser), 0);
+ InitializeCordRepExternal(data, rep);
+ return rep;
+}
+
+// Overload for function reference types that dispatches using a function
+// pointer because there are no `alignof()` or `sizeof()` a function reference.
+// NOLINTNEXTLINE - suppress clang-tidy raw pointer return.
+inline CordRep* NewExternalRep(absl::string_view data,
+ void (&releaser)(absl::string_view)) {
+ return NewExternalRep(data, &releaser);
+}
+
+} // namespace cord_internal
+
+template <typename Releaser>
+Cord MakeCordFromExternal(absl::string_view data, Releaser&& releaser) {
+ Cord cord;
+ cord.contents_.set_tree(::absl::cord_internal::NewExternalRep(
+ data, std::forward<Releaser>(releaser)));
+ return cord;
+}
+
+constexpr Cord::InlineRep::InlineRep(cord_internal::InlineData data)
+ : data_(data) {}
+
+inline Cord::InlineRep::InlineRep(const Cord::InlineRep& src) {
+ data_ = src.data_;
+}
+
+inline Cord::InlineRep::InlineRep(Cord::InlineRep&& src) {
+ data_ = src.data_;
+ src.ResetToEmpty();
+}
+
+inline Cord::InlineRep& Cord::InlineRep::operator=(const Cord::InlineRep& src) {
+ if (this == &src) {
+ return *this;
+ }
+ if (!is_tree() && !src.is_tree()) {
+ data_ = src.data_;
+ return *this;
+ }
+ AssignSlow(src);
+ return *this;
+}
+
+inline Cord::InlineRep& Cord::InlineRep::operator=(
+ Cord::InlineRep&& src) noexcept {
+ if (is_tree()) {
+ ClearSlow();
+ }
+ data_ = src.data_;
+ src.ResetToEmpty();
+ return *this;
+}
+
+inline void Cord::InlineRep::Swap(Cord::InlineRep* rhs) {
+ if (rhs == this) {
+ return;
+ }
+
+ std::swap(data_, rhs->data_);
+}
+
+inline const char* Cord::InlineRep::data() const {
+ return is_tree() ? nullptr : data_.as_chars;
+}
+
+inline absl::cord_internal::CordRep* Cord::InlineRep::tree() const {
+ if (is_tree()) {
+ return data_.as_tree.rep;
+ } else {
+ return nullptr;
+ }
+}
+
+inline bool Cord::InlineRep::empty() const { return tagged_size() == 0; }
+
+inline size_t Cord::InlineRep::size() const {
+ const char tag = tagged_size();
+ if (tag <= kMaxInline) return tag;
+ return static_cast<size_t>(tree()->length);
+}
+
+inline void Cord::InlineRep::set_tree(absl::cord_internal::CordRep* rep) {
+ if (rep == nullptr) {
+ ResetToEmpty();
+ } else {
+ bool was_tree = is_tree();
+ data_.as_tree = {rep, {}, tagged_size()};
+ if (!was_tree) {
+ // If we were not a tree already, set the tag.
+ // Otherwise, leave it alone because it might have the profile bit on.
+ set_tagged_size(kTreeFlag);
+ }
+ }
+}
+
+inline void Cord::InlineRep::replace_tree(absl::cord_internal::CordRep* rep) {
+ ABSL_ASSERT(is_tree());
+ if (ABSL_PREDICT_FALSE(rep == nullptr)) {
+ set_tree(rep);
+ return;
+ }
+ data_.as_tree = {rep, {}, tagged_size()};
+}
+
+inline absl::cord_internal::CordRep* Cord::InlineRep::clear() {
+ absl::cord_internal::CordRep* result = tree();
+ ResetToEmpty();
+ return result;
+}
+
+inline void Cord::InlineRep::CopyToArray(char* dst) const {
+ assert(!is_tree());
+ size_t n = tagged_size();
+ assert(n != 0);
+ cord_internal::SmallMemmove(dst, data_.as_chars, n);
+}
+
+constexpr inline Cord::Cord() noexcept {}
+
+template <typename T>
+constexpr Cord::Cord(strings_internal::StringConstant<T>)
+ : contents_(strings_internal::StringConstant<T>::value.size() <=
+ cord_internal::kMaxInline
+ ? cord_internal::InlineData(
+ strings_internal::StringConstant<T>::value)
+ : cord_internal::InlineData(cord_internal::AsTree{
+ &cord_internal::ConstInitExternalStorage<
+ strings_internal::StringConstant<T>>::value,
+ {},
+ cord_internal::kTreeFlag})) {}
+
+inline Cord& Cord::operator=(const Cord& x) {
+ contents_ = x.contents_;
+ return *this;
+}
+
+inline Cord::Cord(Cord&& src) noexcept : contents_(std::move(src.contents_)) {}
+
+inline void Cord::swap(Cord& other) noexcept {
+ contents_.Swap(&other.contents_);
+}
+
+inline Cord& Cord::operator=(Cord&& x) noexcept {
+ contents_ = std::move(x.contents_);
+ return *this;
+}
+
+extern template Cord::Cord(std::string&& src);
+extern template Cord& Cord::operator=(std::string&& src);
+
+inline size_t Cord::size() const {
+ // Length is 1st field in str.rep_
+ return contents_.size();
+}
+
+inline bool Cord::empty() const { return contents_.empty(); }
+
+inline size_t Cord::EstimatedMemoryUsage() const {
+ size_t result = sizeof(Cord);
+ if (const absl::cord_internal::CordRep* rep = contents_.tree()) {
+ result += MemoryUsageAux(rep);
+ }
+ return result;
+}
+
+inline absl::optional<absl::string_view> Cord::TryFlat() const {
+ absl::cord_internal::CordRep* rep = contents_.tree();
+ if (rep == nullptr) {
+ return absl::string_view(contents_.data(), contents_.size());
+ }
+ absl::string_view fragment;
+ if (GetFlatAux(rep, &fragment)) {
+ return fragment;
+ }
+ return absl::nullopt;
+}
+
+inline absl::string_view Cord::Flatten() {
+ absl::cord_internal::CordRep* rep = contents_.tree();
+ if (rep == nullptr) {
+ return absl::string_view(contents_.data(), contents_.size());
+ } else {
+ absl::string_view already_flat_contents;
+ if (GetFlatAux(rep, &already_flat_contents)) {
+ return already_flat_contents;
+ }
+ }
+ return FlattenSlowPath();
+}
+
+inline void Cord::Append(absl::string_view src) {
+ contents_.AppendArray(src.data(), src.size());
+}
+
+extern template void Cord::Append(std::string&& src);
+extern template void Cord::Prepend(std::string&& src);
+
+inline int Cord::Compare(const Cord& rhs) const {
+ if (!contents_.is_tree() && !rhs.contents_.is_tree()) {
+ return contents_.BitwiseCompare(rhs.contents_);
+ }
+
+ return CompareImpl(rhs);
+}
+
+// Does 'this' cord start/end with rhs
+inline bool Cord::StartsWith(const Cord& rhs) const {
+ if (contents_.IsSame(rhs.contents_)) return true;
+ size_t rhs_size = rhs.size();
+ if (size() < rhs_size) return false;
+ return EqualsImpl(rhs, rhs_size);
+}
+
+inline bool Cord::StartsWith(absl::string_view rhs) const {
+ size_t rhs_size = rhs.size();
+ if (size() < rhs_size) return false;
+ return EqualsImpl(rhs, rhs_size);
+}
+
+inline Cord::ChunkIterator::ChunkIterator(const Cord* cord)
+ : bytes_remaining_(cord->size()) {
+ if (cord->empty()) return;
+ if (cord->contents_.is_tree()) {
+ stack_of_right_children_.push_back(cord->contents_.tree());
+ operator++();
+ } else {
+ current_chunk_ = absl::string_view(cord->contents_.data(), cord->size());
+ }
+}
+
+inline Cord::ChunkIterator& Cord::ChunkIterator::operator++() {
+ ABSL_HARDENING_ASSERT(bytes_remaining_ > 0 &&
+ "Attempted to iterate past `end()`");
+ assert(bytes_remaining_ >= current_chunk_.size());
+ bytes_remaining_ -= current_chunk_.size();
+ if (bytes_remaining_ > 0) {
+ return AdvanceStack();
+ } else {
+ current_chunk_ = {};
+ }
+ return *this;
+}
+
+inline Cord::ChunkIterator Cord::ChunkIterator::operator++(int) {
+ ChunkIterator tmp(*this);
+ operator++();
+ return tmp;
+}
+
+inline bool Cord::ChunkIterator::operator==(const ChunkIterator& other) const {
+ return bytes_remaining_ == other.bytes_remaining_;
+}
+
+inline bool Cord::ChunkIterator::operator!=(const ChunkIterator& other) const {
+ return !(*this == other);
+}
+
+inline Cord::ChunkIterator::reference Cord::ChunkIterator::operator*() const {
+ ABSL_HARDENING_ASSERT(bytes_remaining_ != 0);
+ return current_chunk_;
+}
+
+inline Cord::ChunkIterator::pointer Cord::ChunkIterator::operator->() const {
+ ABSL_HARDENING_ASSERT(bytes_remaining_ != 0);
+ return ¤t_chunk_;
+}
+
+inline void Cord::ChunkIterator::RemoveChunkPrefix(size_t n) {
+ assert(n < current_chunk_.size());
+ current_chunk_.remove_prefix(n);
+ bytes_remaining_ -= n;
+}
+
+inline void Cord::ChunkIterator::AdvanceBytes(size_t n) {
+ if (ABSL_PREDICT_TRUE(n < current_chunk_.size())) {
+ RemoveChunkPrefix(n);
+ } else if (n != 0) {
+ AdvanceBytesSlowPath(n);
+ }
+}
+
+inline Cord::ChunkIterator Cord::chunk_begin() const {
+ return ChunkIterator(this);
+}
+
+inline Cord::ChunkIterator Cord::chunk_end() const { return ChunkIterator(); }
+
+inline Cord::ChunkIterator Cord::ChunkRange::begin() const {
+ return cord_->chunk_begin();
+}
+
+inline Cord::ChunkIterator Cord::ChunkRange::end() const {
+ return cord_->chunk_end();
+}
+
+inline Cord::ChunkRange Cord::Chunks() const { return ChunkRange(this); }
+
+inline Cord::CharIterator& Cord::CharIterator::operator++() {
+ if (ABSL_PREDICT_TRUE(chunk_iterator_->size() > 1)) {
+ chunk_iterator_.RemoveChunkPrefix(1);
+ } else {
+ ++chunk_iterator_;
+ }
+ return *this;
+}
+
+inline Cord::CharIterator Cord::CharIterator::operator++(int) {
+ CharIterator tmp(*this);
+ operator++();
+ return tmp;
+}
+
+inline bool Cord::CharIterator::operator==(const CharIterator& other) const {
+ return chunk_iterator_ == other.chunk_iterator_;
+}
+
+inline bool Cord::CharIterator::operator!=(const CharIterator& other) const {
+ return !(*this == other);
+}
+
+inline Cord::CharIterator::reference Cord::CharIterator::operator*() const {
+ return *chunk_iterator_->data();
+}
+
+inline Cord::CharIterator::pointer Cord::CharIterator::operator->() const {
+ return chunk_iterator_->data();
+}
+
+inline Cord Cord::AdvanceAndRead(CharIterator* it, size_t n_bytes) {
+ assert(it != nullptr);
+ return it->chunk_iterator_.AdvanceAndReadBytes(n_bytes);
+}
+
+inline void Cord::Advance(CharIterator* it, size_t n_bytes) {
+ assert(it != nullptr);
+ it->chunk_iterator_.AdvanceBytes(n_bytes);
+}
+
+inline absl::string_view Cord::ChunkRemaining(const CharIterator& it) {
+ return *it.chunk_iterator_;
+}
+
+inline Cord::CharIterator Cord::char_begin() const {
+ return CharIterator(this);
+}
+
+inline Cord::CharIterator Cord::char_end() const { return CharIterator(); }
+
+inline Cord::CharIterator Cord::CharRange::begin() const {
+ return cord_->char_begin();
+}
+
+inline Cord::CharIterator Cord::CharRange::end() const {
+ return cord_->char_end();
+}
+
+inline Cord::CharRange Cord::Chars() const { return CharRange(this); }
+
+inline void Cord::ForEachChunk(
+ absl::FunctionRef<void(absl::string_view)> callback) const {
+ absl::cord_internal::CordRep* rep = contents_.tree();
+ if (rep == nullptr) {
+ callback(absl::string_view(contents_.data(), contents_.size()));
+ } else {
+ return ForEachChunkAux(rep, callback);
+ }
+}
+
+// Nonmember Cord-to-Cord relational operarators.
+inline bool operator==(const Cord& lhs, const Cord& rhs) {
+ if (lhs.contents_.IsSame(rhs.contents_)) return true;
+ size_t rhs_size = rhs.size();
+ if (lhs.size() != rhs_size) return false;
+ return lhs.EqualsImpl(rhs, rhs_size);
+}
+
+inline bool operator!=(const Cord& x, const Cord& y) { return !(x == y); }
+inline bool operator<(const Cord& x, const Cord& y) {
+ return x.Compare(y) < 0;
+}
+inline bool operator>(const Cord& x, const Cord& y) {
+ return x.Compare(y) > 0;
+}
+inline bool operator<=(const Cord& x, const Cord& y) {
+ return x.Compare(y) <= 0;
+}
+inline bool operator>=(const Cord& x, const Cord& y) {
+ return x.Compare(y) >= 0;
+}
+
+// Nonmember Cord-to-absl::string_view relational operators.
+//
+// Due to implicit conversions, these also enable comparisons of Cord with
+// with std::string, ::string, and const char*.
+inline bool operator==(const Cord& lhs, absl::string_view rhs) {
+ size_t lhs_size = lhs.size();
+ size_t rhs_size = rhs.size();
+ if (lhs_size != rhs_size) return false;
+ return lhs.EqualsImpl(rhs, rhs_size);
+}
+
+inline bool operator==(absl::string_view x, const Cord& y) { return y == x; }
+inline bool operator!=(const Cord& x, absl::string_view y) { return !(x == y); }
+inline bool operator!=(absl::string_view x, const Cord& y) { return !(x == y); }
+inline bool operator<(const Cord& x, absl::string_view y) {
+ return x.Compare(y) < 0;
+}
+inline bool operator<(absl::string_view x, const Cord& y) {
+ return y.Compare(x) > 0;
+}
+inline bool operator>(const Cord& x, absl::string_view y) { return y < x; }
+inline bool operator>(absl::string_view x, const Cord& y) { return y < x; }
+inline bool operator<=(const Cord& x, absl::string_view y) { return !(y < x); }
+inline bool operator<=(absl::string_view x, const Cord& y) { return !(y < x); }
+inline bool operator>=(const Cord& x, absl::string_view y) { return !(x < y); }
+inline bool operator>=(absl::string_view x, const Cord& y) { return !(x < y); }
+
+// Some internals exposed to test code.
+namespace strings_internal {
+class CordTestAccess {
+ public:
+ static size_t FlatOverhead();
+ static size_t MaxFlatLength();
+ static size_t SizeofCordRepConcat();
+ static size_t SizeofCordRepExternal();
+ static size_t SizeofCordRepSubstring();
+ static size_t FlatTagToLength(uint8_t tag);
+ static uint8_t LengthToTag(size_t s);
+};
+} // namespace strings_internal
+ABSL_NAMESPACE_END
+} // namespace absl
+
+#endif // ABSL_STRINGS_CORD_H_