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-rw-r--r--third_party/abseil-cpp/absl/strings/cord.h186
1 files changed, 145 insertions, 41 deletions
diff --git a/third_party/abseil-cpp/absl/strings/cord.h b/third_party/abseil-cpp/absl/strings/cord.h
index fa9cb913fd..e758f1cdfb 100644
--- a/third_party/abseil-cpp/absl/strings/cord.h
+++ b/third_party/abseil-cpp/absl/strings/cord.h
@@ -70,6 +70,7 @@
#include <string>
#include <type_traits>
+#include "absl/base/config.h"
#include "absl/base/internal/endian.h"
#include "absl/base/internal/per_thread_tls.h"
#include "absl/base/macros.h"
@@ -80,6 +81,11 @@
#include "absl/strings/internal/cord_internal.h"
#include "absl/strings/internal/cord_rep_ring.h"
#include "absl/strings/internal/cord_rep_ring_reader.h"
+#include "absl/strings/internal/cordz_functions.h"
+#include "absl/strings/internal/cordz_info.h"
+#include "absl/strings/internal/cordz_statistics.h"
+#include "absl/strings/internal/cordz_update_scope.h"
+#include "absl/strings/internal/cordz_update_tracker.h"
#include "absl/strings/internal/resize_uninitialized.h"
#include "absl/strings/internal/string_constant.h"
#include "absl/strings/string_view.h"
@@ -664,10 +670,24 @@ class Cord {
explicit constexpr Cord(strings_internal::StringConstant<T>);
private:
+ using CordRep = absl::cord_internal::CordRep;
+ using CordRepFlat = absl::cord_internal::CordRepFlat;
+ using CordzInfo = cord_internal::CordzInfo;
+ using CordzUpdateScope = cord_internal::CordzUpdateScope;
+ using CordzUpdateTracker = cord_internal::CordzUpdateTracker;
+ using InlineData = cord_internal::InlineData;
+ using MethodIdentifier = CordzUpdateTracker::MethodIdentifier;
+
+ // Creates a cord instance with `method` representing the originating
+ // public API call causing the cord to be created.
+ explicit Cord(absl::string_view src, MethodIdentifier method);
+
friend class CordTestPeer;
friend bool operator==(const Cord& lhs, const Cord& rhs);
friend bool operator==(const Cord& lhs, absl::string_view rhs);
+ friend const CordzInfo* GetCordzInfoForTesting(const Cord& cord);
+
// 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;
@@ -687,6 +707,7 @@ class Cord {
static_assert(kMaxInline >= sizeof(absl::cord_internal::CordRep*), "");
constexpr InlineRep() : data_() {}
+ explicit InlineRep(InlineData::DefaultInitType init) : data_(init) {}
InlineRep(const InlineRep& src);
InlineRep(InlineRep&& src);
InlineRep& operator=(const InlineRep& src);
@@ -704,23 +725,56 @@ class Cord {
// Returns nullptr if holding bytes
absl::cord_internal::CordRep* tree() const;
absl::cord_internal::CordRep* as_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);
+ void AppendArray(absl::string_view src, MethodIdentifier method);
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);
+
+ // Creates a CordRepFlat instance from the current inlined data with `extra'
+ // bytes of desired additional capacity.
+ CordRepFlat* MakeFlatWithExtraCapacity(size_t extra);
+
+ // Sets the tree value for this instance. `rep` must not be null.
+ // Requires the current instance to hold a tree, and a lock to be held on
+ // any CordzInfo referenced by this instance. The latter is enforced through
+ // the CordzUpdateScope argument. If the current instance is sampled, then
+ // the CordzInfo instance is updated to reference the new `rep` value.
+ void SetTree(CordRep* rep, const CordzUpdateScope& scope);
+
+ // Identical to SetTree(), except that `rep` is allowed to be null, in
+ // which case the current instance is reset to an empty value.
+ void SetTreeOrEmpty(CordRep* rep, const CordzUpdateScope& scope);
+
+ // Sets the tree value for this instance, and randomly samples this cord.
+ // This function disregards existing contents in `data_`, and should be
+ // called when a Cord is 'promoted' from an 'uninitialized' or 'inlined'
+ // value to a non-inlined (tree / ring) value.
+ void EmplaceTree(CordRep* rep, MethodIdentifier method);
+
+ // Identical to EmplaceTree, except that it copies the parent stack from
+ // the provided `parent` data if the parent is sampled.
+ void EmplaceTree(CordRep* rep, const InlineData& parent,
+ MethodIdentifier method);
+
+ // Commits the change of a newly created, or updated `rep` root value into
+ // this cord. `old_rep` indicates the old (inlined or tree) value of the
+ // cord, and determines if the commit invokes SetTree() or EmplaceTree().
+ void CommitTree(const CordRep* old_rep, CordRep* rep,
+ const CordzUpdateScope& scope, MethodIdentifier method);
+
+ void AppendTreeToInlined(CordRep* tree, MethodIdentifier method);
+ void AppendTreeToTree(CordRep* tree, MethodIdentifier method);
+ void AppendTree(CordRep* tree, MethodIdentifier method);
+ void PrependTreeToInlined(CordRep* tree, MethodIdentifier method);
+ void PrependTreeToTree(CordRep* tree, MethodIdentifier method);
+ void PrependTree(CordRep* tree, MethodIdentifier method);
+
+ template <bool has_length>
+ void GetAppendRegion(char** region, size_t* size, size_t length);
+
bool IsSame(const InlineRep& other) const {
return memcmp(&data_, &other.data_, sizeof(data_)) == 0;
}
@@ -776,8 +830,8 @@ class Cord {
friend class Cord;
void AssignSlow(const InlineRep& src);
- // Unrefs the tree, stops profiling, and zeroes the contents
- void ClearSlow();
+ // Unrefs the tree and stops profiling.
+ void UnrefTree();
void ResetToEmpty() { data_ = {}; }
@@ -828,6 +882,10 @@ class Cord {
template <typename C>
void AppendImpl(C&& src);
+ // Assigns the value in 'src' to this instance, 'stealing' its contents.
+ // Requires src.length() > kMaxBytesToCopy.
+ Cord& AssignLargeString(std::string&& src);
+
// Helper for AbslHashValue().
template <typename H>
H HashFragmented(H hash_state) const {
@@ -930,8 +988,11 @@ inline CordRep* NewExternalRep(absl::string_view data,
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)));
+ if (auto* rep = ::absl::cord_internal::NewExternalRep(
+ data, std::forward<Releaser>(releaser))) {
+ cord.contents_.EmplaceTree(rep,
+ Cord::MethodIdentifier::kMakeCordFromExternal);
+ }
return cord;
}
@@ -939,15 +1000,16 @@ constexpr Cord::InlineRep::InlineRep(cord_internal::InlineData data)
: data_(data) {}
inline Cord::InlineRep::InlineRep(const Cord::InlineRep& src)
- : data_(src.data_) {
- if (is_tree()) {
- data_.clear_cordz_info();
- absl::cord_internal::CordRep::Ref(as_tree());
+ : data_(InlineData::kDefaultInit) {
+ if (CordRep* tree = src.tree()) {
+ EmplaceTree(CordRep::Ref(tree), src.data_,
+ CordzUpdateTracker::kConstructorCord);
+ } else {
+ data_ = src.data_;
}
}
-inline Cord::InlineRep::InlineRep(Cord::InlineRep&& src) {
- data_ = src.data_;
+inline Cord::InlineRep::InlineRep(Cord::InlineRep&& src) : data_(src.data_) {
src.ResetToEmpty();
}
@@ -966,7 +1028,7 @@ inline Cord::InlineRep& Cord::InlineRep::operator=(const Cord::InlineRep& src) {
inline Cord::InlineRep& Cord::InlineRep::operator=(
Cord::InlineRep&& src) noexcept {
if (is_tree()) {
- ClearSlow();
+ UnrefTree();
}
data_ = src.data_;
src.ResetToEmpty();
@@ -1003,31 +1065,62 @@ inline size_t Cord::InlineRep::size() const {
return is_tree() ? as_tree()->length : inline_size();
}
-inline void Cord::InlineRep::set_tree(absl::cord_internal::CordRep* rep) {
- if (rep == nullptr) {
- ResetToEmpty();
+inline cord_internal::CordRepFlat* Cord::InlineRep::MakeFlatWithExtraCapacity(
+ size_t extra) {
+ static_assert(cord_internal::kMinFlatLength >= sizeof(data_), "");
+ size_t len = data_.inline_size();
+ auto* result = CordRepFlat::New(len + extra);
+ result->length = len;
+ memcpy(result->Data(), data_.as_chars(), sizeof(data_));
+ return result;
+}
+
+inline void Cord::InlineRep::EmplaceTree(CordRep* rep,
+ MethodIdentifier method) {
+ assert(rep);
+ data_.make_tree(rep);
+ CordzInfo::MaybeTrackCord(data_, method);
+}
+
+inline void Cord::InlineRep::EmplaceTree(CordRep* rep, const InlineData& parent,
+ MethodIdentifier method) {
+ data_.make_tree(rep);
+ CordzInfo::MaybeTrackCord(data_, parent, method);
+}
+
+inline void Cord::InlineRep::SetTree(CordRep* rep,
+ const CordzUpdateScope& scope) {
+ assert(rep);
+ assert(data_.is_tree());
+ data_.set_tree(rep);
+ scope.SetCordRep(rep);
+}
+
+inline void Cord::InlineRep::SetTreeOrEmpty(CordRep* rep,
+ const CordzUpdateScope& scope) {
+ assert(data_.is_tree());
+ if (rep) {
+ data_.set_tree(rep);
} else {
- if (data_.is_tree()) {
- // `data_` already holds a 'tree' value and an optional cordz_info value.
- // Replace the tree value only, leaving the cordz_info value unchanged.
- data_.set_tree(rep);
- } else {
- // `data_` contains inlined data: initialize data_ to tree value `rep`.
- data_.make_tree(rep);
- }
+ data_ = {};
}
+ scope.SetCordRep(rep);
}
-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;
+inline void Cord::InlineRep::CommitTree(const CordRep* old_rep, CordRep* rep,
+ const CordzUpdateScope& scope,
+ MethodIdentifier method) {
+ if (old_rep) {
+ SetTree(rep, scope);
+ } else {
+ EmplaceTree(rep, method);
}
- data_.set_tree(rep);
}
inline absl::cord_internal::CordRep* Cord::InlineRep::clear() {
+ if (is_tree()) {
+ CordzInfo::MaybeUntrackCord(cordz_info());
+ }
absl::cord_internal::CordRep* result = tree();
ResetToEmpty();
return result;
@@ -1042,6 +1135,9 @@ inline void Cord::InlineRep::CopyToArray(char* dst) const {
constexpr inline Cord::Cord() noexcept {}
+inline Cord::Cord(absl::string_view src)
+ : Cord(src, CordzUpdateTracker::kConstructorString) {}
+
template <typename T>
constexpr Cord::Cord(strings_internal::StringConstant<T>)
: contents_(strings_internal::StringConstant<T>::value.size() <=
@@ -1057,6 +1153,15 @@ inline Cord& Cord::operator=(const Cord& x) {
return *this;
}
+template <typename T, Cord::EnableIfString<T>>
+Cord& Cord::operator=(T&& src) {
+ if (src.size() <= cord_internal::kMaxBytesToCopy) {
+ return operator=(absl::string_view(src));
+ } else {
+ return AssignLargeString(std::forward<T>(src));
+ }
+}
+
inline Cord::Cord(const Cord& src) : contents_(src.contents_) {}
inline Cord::Cord(Cord&& src) noexcept : contents_(std::move(src.contents_)) {}
@@ -1071,7 +1176,6 @@ inline Cord& Cord::operator=(Cord&& x) noexcept {
}
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_
@@ -1114,7 +1218,7 @@ inline absl::string_view Cord::Flatten() {
}
inline void Cord::Append(absl::string_view src) {
- contents_.AppendArray(src.data(), src.size());
+ contents_.AppendArray(src, CordzUpdateTracker::kAppendString);
}
extern template void Cord::Append(std::string&& src);
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-14 13:52:06 +0000