[libc++abi] Reuse libc++'s refstring.h header instead of copying it
This has been a long-standing TODO item, however we have now been requiring
a monorepo layout to build libc++ and libc++abi for a while now. Hence,
we can fix this code duplication issue now.
Note that it's still not super pretty to reach into libc++ to include
headers, but it's better than having duplicated code which can get out
of sync.
GitOrigin-RevId: a7b65741441556d295079fc4f2391d99fd1c1111
diff --git a/src/include/refstring.h b/src/include/refstring.h
deleted file mode 100644
index 5905b5c..0000000
--- a/src/include/refstring.h
+++ /dev/null
@@ -1,131 +0,0 @@
-//===------------------------ __refstring ---------------------------------===//
-//
-// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
-// See https://llvm.org/LICENSE.txt for license information.
-// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
-//
-//===----------------------------------------------------------------------===//
-
-// FIXME: This file is copied from libcxx/src/include/refstring.h. Instead of
-// duplicating the file in libc++abi we should require that the libc++ sources
-// are available when building libc++abi.
-
-#ifndef _LIBCPPABI_REFSTRING_H
-#define _LIBCPPABI_REFSTRING_H
-
-#include <__config>
-#include <stdexcept>
-#include <cstddef>
-#include <cstring>
-#ifdef __APPLE__
-#include <dlfcn.h>
-#include <mach-o/dyld.h>
-#endif
-#include "atomic_support.h"
-
-_LIBCPP_BEGIN_NAMESPACE_STD
-
-namespace __refstring_imp { namespace {
-typedef int count_t;
-
-struct _Rep_base {
- std::size_t len;
- std::size_t cap;
- count_t count;
-};
-
-inline _Rep_base* rep_from_data(const char *data_) noexcept {
- char *data = const_cast<char *>(data_);
- return reinterpret_cast<_Rep_base *>(data - sizeof(_Rep_base));
-}
-
-inline char * data_from_rep(_Rep_base *rep) noexcept {
- char *data = reinterpret_cast<char *>(rep);
- return data + sizeof(*rep);
-}
-
-#if defined(__APPLE__)
-inline
-const char* compute_gcc_empty_string_storage() _NOEXCEPT
-{
- void* handle = dlopen("/usr/lib/libstdc++.6.dylib", RTLD_NOLOAD);
- if (handle == nullptr)
- return nullptr;
- void* sym = dlsym(handle, "_ZNSs4_Rep20_S_empty_rep_storageE");
- if (sym == nullptr)
- return nullptr;
- return data_from_rep(reinterpret_cast<_Rep_base *>(sym));
-}
-
-inline
-const char*
-get_gcc_empty_string_storage() _NOEXCEPT
-{
- static const char* p = compute_gcc_empty_string_storage();
- return p;
-}
-#endif
-
-}} // namespace __refstring_imp
-
-using namespace __refstring_imp;
-
-inline
-__libcpp_refstring::__libcpp_refstring(const char* msg) {
- std::size_t len = strlen(msg);
- _Rep_base* rep = static_cast<_Rep_base *>(::operator new(sizeof(*rep) + len + 1));
- rep->len = len;
- rep->cap = len;
- rep->count = 0;
- char *data = data_from_rep(rep);
- std::memcpy(data, msg, len + 1);
- __imp_ = data;
-}
-
-inline
-__libcpp_refstring::__libcpp_refstring(const __libcpp_refstring &s) _NOEXCEPT
- : __imp_(s.__imp_)
-{
- if (__uses_refcount())
- __libcpp_atomic_add(&rep_from_data(__imp_)->count, 1);
-}
-
-inline
-__libcpp_refstring& __libcpp_refstring::operator=(__libcpp_refstring const& s) _NOEXCEPT {
- bool adjust_old_count = __uses_refcount();
- struct _Rep_base *old_rep = rep_from_data(__imp_);
- __imp_ = s.__imp_;
- if (__uses_refcount())
- __libcpp_atomic_add(&rep_from_data(__imp_)->count, 1);
- if (adjust_old_count)
- {
- if (__libcpp_atomic_add(&old_rep->count, count_t(-1)) < 0)
- {
- ::operator delete(old_rep);
- }
- }
- return *this;
-}
-
-inline
-__libcpp_refstring::~__libcpp_refstring() {
- if (__uses_refcount()) {
- _Rep_base* rep = rep_from_data(__imp_);
- if (__libcpp_atomic_add(&rep->count, count_t(-1)) < 0) {
- ::operator delete(rep);
- }
- }
-}
-
-inline
-bool __libcpp_refstring::__uses_refcount() const {
-#ifdef __APPLE__
- return __imp_ != get_gcc_empty_string_storage();
-#else
- return true;
-#endif
-}
-
-_LIBCPP_END_NAMESPACE_STD
-
-#endif //_LIBCPPABI_REFSTRING_H
diff --git a/src/stdlib_stdexcept.cpp b/src/stdlib_stdexcept.cpp
index 2cff8ee..4a464e4 100644
--- a/src/stdlib_stdexcept.cpp
+++ b/src/stdlib_stdexcept.cpp
@@ -6,7 +6,7 @@
//
//===----------------------------------------------------------------------===//
-#include "include/refstring.h"
+#include "../../libcxx/src/include/refstring.h"
#include "stdexcept"
#include "new"
#include <cstdlib>
