From patchwork Sat Mar 17 23:49:02 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Simon Marchi X-Patchwork-Id: 26358 Received: (qmail 84433 invoked by alias); 17 Mar 2018 23:49:22 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Delivered-To: mailing list gdb-patches@sourceware.org Received: (qmail 84322 invoked by uid 89); 17 Mar 2018 23:49:21 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-26.2 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_SOFTFAIL autolearn=ham version=3.3.2 spammy=UD:access, seamlessly X-HELO: barracuda.ebox.ca Received: from barracuda.ebox.ca (HELO barracuda.ebox.ca) (96.127.255.19) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Sat, 17 Mar 2018 23:49:17 +0000 X-ASG-Debug-ID: 1521330546-0c856e618a4b1c80001-fS2M51 Received: from smtp.ebox.ca (smtp.electronicbox.net [96.127.255.82]) by barracuda.ebox.ca with ESMTP id t4PE43GjQ8Rl58cX (version=TLSv1 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Sat, 17 Mar 2018 19:49:06 -0400 (EDT) X-Barracuda-Envelope-From: simon.marchi@polymtl.ca X-Barracuda-RBL-Trusted-Forwarder: 96.127.255.82 Received: from simark.lan (unknown [192.222.164.54]) by smtp.ebox.ca (Postfix) with ESMTP id EB865441D64; Sat, 17 Mar 2018 19:49:05 -0400 (EDT) From: Simon Marchi X-Barracuda-Effective-Source-IP: 192-222-164-54.qc.cable.ebox.net[192.222.164.54] X-Barracuda-Apparent-Source-IP: 192.222.164.54 X-Barracuda-RBL-IP: 192.222.164.54 To: gdb-patches@sourceware.org Cc: Simon Marchi Subject: [PATCH 2/2] Add gdb::string_view Date: Sat, 17 Mar 2018 19:49:02 -0400 X-ASG-Orig-Subj: [PATCH 2/2] Add gdb::string_view Message-Id: <20180317234902.18278-2-simon.marchi@polymtl.ca> In-Reply-To: <20180317234902.18278-1-simon.marchi@polymtl.ca> References: <20180317234902.18278-1-simon.marchi@polymtl.ca> X-Barracuda-Connect: smtp.electronicbox.net[96.127.255.82] X-Barracuda-Start-Time: 1521330546 X-Barracuda-Encrypted: DHE-RSA-AES256-SHA X-Barracuda-URL: https://96.127.255.19:443/cgi-mod/mark.cgi X-Barracuda-Scan-Msg-Size: 23455 X-Barracuda-BRTS-Status: 1 X-Barracuda-Spam-Score: 0.00 X-Barracuda-Spam-Status: No, SCORE=0.00 using global scores of TAG_LEVEL=1000.0 QUARANTINE_LEVEL=1000.0 KILL_LEVEL=8.0 tests= X-Barracuda-Spam-Report: Code version 3.2, rules version 3.2.3.49056 Rule breakdown below pts rule name description ---- ---------------------- -------------------------------------------------- X-IsSubscribed: yes We had a few times the need for a data structure that does essentially what C++17's std::string_view does, which is to give an std::string-like interface (only the read-only operations) to an arbitrary character buffer. I first copied the string_view file from today's gcc master (b427286632d7) and adapted it (I don't think there should be any legal issues since the copyright should already belong to the FSF): - I removed things related to wstring_view, u16string_view and u32string_view (I don't think we need them, but we can always add them later). - I removed usages of _GLIBCXX_BEGIN_NAMESPACE_VERSION and _GLIBCXX_END_NAMESPACE_VERSION. - I put the code in the gdb namespace. I had to add a few "std::" in front of std type usages. - I added a constructor that builds a string_view from an std::string, so that we can pass strings to string_view parameters seamlessly. Normally, that's handled by "operator __sv_type" in the std::string declaration, but it only exists when building with c++17. - When building with >= c++17, gdb::string_view is an alias of std::string_view. The result is close enough to the original file that if we ever need to update it, it should be easy enough to compare it with the new version in a diff editor and merge the new changes in. gdb/ChangeLog: * common/string_view.h: New file. * cli/cli-script.c (user_args) : Change element type to gdb::string_view. --- gdb/cli/cli-script.c | 17 +- gdb/common/string_view.h | 594 +++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 597 insertions(+), 14 deletions(-) create mode 100644 gdb/common/string_view.h diff --git a/gdb/cli/cli-script.c b/gdb/cli/cli-script.c index 366c42227c62..e705b7a8da70 100644 --- a/gdb/cli/cli-script.c +++ b/gdb/cli/cli-script.c @@ -32,6 +32,7 @@ #include "extension.h" #include "interps.h" #include "compile/compile.h" +#include "common/string_view.h" #include @@ -54,18 +55,6 @@ static int command_nest_depth = 1; /* This is to prevent certain commands being printed twice. */ static int suppress_next_print_command_trace = 0; -/* A non-owning slice of a string. */ - -struct string_view -{ - string_view (const char *str_, size_t len_) - : str (str_), len (len_) - {} - - const char *str; - size_t len; -}; - /* Structure for arguments to user defined functions. */ class user_args @@ -91,7 +80,7 @@ private: std::string m_command_line; /* The arguments. Each element points inside M_COMMAND_LINE. */ - std::vector m_args; + std::vector m_args; }; /* The stack of arguments passed to user defined functions. We need a @@ -827,7 +816,7 @@ user_args::insert_args (const char *line) const error (_("Missing argument %ld in user function."), i); else { - new_line.append (m_args[i].str, m_args[i].len); + new_line.append (m_args[i].data (), m_args[i].length ()); line = tmp; } } diff --git a/gdb/common/string_view.h b/gdb/common/string_view.h new file mode 100644 index 000000000000..710049dbf0eb --- /dev/null +++ b/gdb/common/string_view.h @@ -0,0 +1,594 @@ +// Components for manipulating non-owning sequences of characters -*- C++ -*- + +// Note: This file has been stolen from the gcc repo +// (libstdc++-v3/include/std/string_view) and has local modifications. + +// Copyright (C) 2013-2017 Free Software Foundation, Inc. +// +// This file is part of the GNU ISO C++ Library. This library is free +// software; you can redistribute it and/or modify it under the +// terms of the GNU General Public License as published by the +// Free Software Foundation; either version 3, or (at your option) +// any later version. + +// This library is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. + +// Under Section 7 of GPL version 3, you are granted additional +// permissions described in the GCC Runtime Library Exception, version +// 3.1, as published by the Free Software Foundation. + +// You should have received a copy of the GNU General Public License and +// a copy of the GCC Runtime Library Exception along with this program; +// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see +// . + + +// +// N3762 basic_string_view library +// + +#ifndef STRING_VIEW_H +#define STRING_VIEW_H 1 + +#if __cplusplus >= 201703L + +#include + +namespace gdb { + using string_view = std::string_view; +} /* namespace gdb */ + +#else /* __cplusplus >= 201703L */ + +#include +#include +#include +#include +#include + +namespace gdb { + /** + * @class basic_string_view + * @brief A non-owning reference to a string. + * + * @ingroup strings + * @ingroup sequences + * + * @tparam _CharT Type of character + * @tparam _Traits Traits for character type, defaults to + * char_traits<_CharT>. + * + * A basic_string_view looks like this: + * + * @code + * _CharT* _M_str + * size_t _M_len + * @endcode + */ + template> + class basic_string_view + { + public: + + // types + using traits_type = _Traits; + using value_type = _CharT; + using pointer = const _CharT*; + using const_pointer = const _CharT*; + using reference = const _CharT&; + using const_reference = const _CharT&; + using const_iterator = const _CharT*; + using iterator = const_iterator; + using const_reverse_iterator = std::reverse_iterator; + using reverse_iterator = const_reverse_iterator; + using size_type = size_t; + using difference_type = ptrdiff_t; + static constexpr size_type npos = size_type(-1); + + // [string.view.cons], construct/copy + + constexpr + basic_string_view() noexcept + : _M_len{0}, _M_str{nullptr} + { } + + constexpr basic_string_view(const basic_string_view&) noexcept = default; + + constexpr basic_string_view(const _CharT* __str) noexcept + : _M_len{__str == nullptr ? 0 : traits_type::length(__str)}, + _M_str{__str} + { } + + constexpr + basic_string_view(const _CharT* __str, size_type __len) noexcept + : _M_len{__len}, _M_str{__str} + { } + + constexpr + basic_string_view(const std::string &__str) noexcept + : _M_len{__str.length()}, _M_str{__str.c_str()} + { } + + constexpr basic_string_view& + operator=(const basic_string_view&) noexcept = default; + + // [string.view.iterators], iterators + + constexpr const_iterator + begin() const noexcept + { return this->_M_str; } + + constexpr const_iterator + end() const noexcept + { return this->_M_str + this->_M_len; } + + constexpr const_iterator + cbegin() const noexcept + { return this->_M_str; } + + constexpr const_iterator + cend() const noexcept + { return this->_M_str + this->_M_len; } + + constexpr const_reverse_iterator + rbegin() const noexcept + { return const_reverse_iterator(this->end()); } + + constexpr const_reverse_iterator + rend() const noexcept + { return const_reverse_iterator(this->begin()); } + + constexpr const_reverse_iterator + crbegin() const noexcept + { return const_reverse_iterator(this->end()); } + + constexpr const_reverse_iterator + crend() const noexcept + { return const_reverse_iterator(this->begin()); } + + // [string.view.capacity], capacity + + constexpr size_type + size() const noexcept + { return this->_M_len; } + + constexpr size_type + length() const noexcept + { return _M_len; } + + constexpr size_type + max_size() const noexcept + { + return (npos - sizeof(size_type) - sizeof(void*)) + / sizeof(value_type) / 4; + } + + constexpr bool + empty() const noexcept + { return this->_M_len == 0; } + + // [string.view.access], element access + + constexpr const _CharT& + operator[](size_type __pos) const noexcept + { + // TODO: Assert to restore in a way compatible with the constexpr. + // __glibcxx_assert(__pos < this->_M_len); + return *(this->_M_str + __pos); + } + + constexpr const _CharT& + at(size_type __pos) const + { + if (__pos >= _M_len) + __throw_out_of_range_fmt(__N("basic_string_view::at: __pos " + "(which is %zu) >= this->size() " + "(which is %zu)"), __pos, this->size()); + return *(this->_M_str + __pos); + } + + constexpr const _CharT& + front() const noexcept + { + // TODO: Assert to restore in a way compatible with the constexpr. + // __glibcxx_assert(this->_M_len > 0); + return *this->_M_str; + } + + constexpr const _CharT& + back() const noexcept + { + // TODO: Assert to restore in a way compatible with the constexpr. + // __glibcxx_assert(this->_M_len > 0); + return *(this->_M_str + this->_M_len - 1); + } + + constexpr const _CharT* + data() const noexcept + { return this->_M_str; } + + // [string.view.modifiers], modifiers: + + constexpr void + remove_prefix(size_type __n) noexcept + { + __glibcxx_assert(this->_M_len >= __n); + this->_M_str += __n; + this->_M_len -= __n; + } + + constexpr void + remove_suffix(size_type __n) noexcept + { this->_M_len -= __n; } + + constexpr void + swap(basic_string_view& __sv) noexcept + { + auto __tmp = *this; + *this = __sv; + __sv = __tmp; + } + + + // [string.view.ops], string operations: + + size_type + copy(_CharT* __str, size_type __n, size_type __pos = 0) const + { + __glibcxx_requires_string_len(__str, __n); + __pos = _M_check(__pos, "basic_string_view::copy"); + const size_type __rlen = std::min(__n, _M_len - __pos); + for (auto __begin = this->_M_str + __pos, + __end = __begin + __rlen; __begin != __end;) + *__str++ = *__begin++; + return __rlen; + } + + + // [string.view.ops], string operations: + + constexpr basic_string_view + substr(size_type __pos, size_type __n = npos) const noexcept(false) + { + __pos = _M_check(__pos, "basic_string_view::substr"); + const size_type __rlen = std::min(__n, _M_len - __pos); + return basic_string_view{_M_str + __pos, __rlen}; + } + + constexpr int + compare(basic_string_view __str) const noexcept + { + const size_type __rlen = std::min(this->_M_len, __str._M_len); + int __ret = traits_type::compare(this->_M_str, __str._M_str, __rlen); + if (__ret == 0) + __ret = _S_compare(this->_M_len, __str._M_len); + return __ret; + } + + constexpr int + compare(size_type __pos1, size_type __n1, basic_string_view __str) const + { return this->substr(__pos1, __n1).compare(__str); } + + constexpr int + compare(size_type __pos1, size_type __n1, + basic_string_view __str, size_type __pos2, size_type __n2) const + { + return this->substr(__pos1, __n1).compare(__str.substr(__pos2, __n2)); + } + + constexpr int + compare(const _CharT* __str) const noexcept + { return this->compare(basic_string_view{__str}); } + + constexpr int + compare(size_type __pos1, size_type __n1, const _CharT* __str) const + { return this->substr(__pos1, __n1).compare(basic_string_view{__str}); } + + constexpr int + compare(size_type __pos1, size_type __n1, + const _CharT* __str, size_type __n2) const noexcept(false) + { + return this->substr(__pos1, __n1) + .compare(basic_string_view(__str, __n2)); + } + + constexpr size_type + find(basic_string_view __str, size_type __pos = 0) const noexcept + { return this->find(__str._M_str, __pos, __str._M_len); } + + constexpr size_type + find(_CharT __c, size_type __pos = 0) const noexcept; + + constexpr size_type + find(const _CharT* __str, size_type __pos, size_type __n) const noexcept; + + constexpr size_type + find(const _CharT* __str, size_type __pos = 0) const noexcept + { return this->find(__str, __pos, traits_type::length(__str)); } + + constexpr size_type + rfind(basic_string_view __str, size_type __pos = npos) const noexcept + { return this->rfind(__str._M_str, __pos, __str._M_len); } + + constexpr size_type + rfind(_CharT __c, size_type __pos = npos) const noexcept; + + constexpr size_type + rfind(const _CharT* __str, size_type __pos, size_type __n) const noexcept; + + constexpr size_type + rfind(const _CharT* __str, size_type __pos = npos) const noexcept + { return this->rfind(__str, __pos, traits_type::length(__str)); } + + constexpr size_type + find_first_of(basic_string_view __str, size_type __pos = 0) const noexcept + { return this->find_first_of(__str._M_str, __pos, __str._M_len); } + + constexpr size_type + find_first_of(_CharT __c, size_type __pos = 0) const noexcept + { return this->find(__c, __pos); } + + constexpr size_type + find_first_of(const _CharT* __str, size_type __pos, size_type __n) const noexcept; + + constexpr size_type + find_first_of(const _CharT* __str, size_type __pos = 0) const noexcept + { return this->find_first_of(__str, __pos, traits_type::length(__str)); } + + constexpr size_type + find_last_of(basic_string_view __str, + size_type __pos = npos) const noexcept + { return this->find_last_of(__str._M_str, __pos, __str._M_len); } + + constexpr size_type + find_last_of(_CharT __c, size_type __pos=npos) const noexcept + { return this->rfind(__c, __pos); } + + constexpr size_type + find_last_of(const _CharT* __str, size_type __pos, + size_type __n) const noexcept; + + constexpr size_type + find_last_of(const _CharT* __str, size_type __pos = npos) const noexcept + { return this->find_last_of(__str, __pos, traits_type::length(__str)); } + + constexpr size_type + find_first_not_of(basic_string_view __str, + size_type __pos = 0) const noexcept + { return this->find_first_not_of(__str._M_str, __pos, __str._M_len); } + + constexpr size_type + find_first_not_of(_CharT __c, size_type __pos = 0) const noexcept; + + constexpr size_type + find_first_not_of(const _CharT* __str, + size_type __pos, size_type __n) const noexcept; + + constexpr size_type + find_first_not_of(const _CharT* __str, size_type __pos = 0) const noexcept + { + return this->find_first_not_of(__str, __pos, + traits_type::length(__str)); + } + + constexpr size_type + find_last_not_of(basic_string_view __str, + size_type __pos = npos) const noexcept + { return this->find_last_not_of(__str._M_str, __pos, __str._M_len); } + + constexpr size_type + find_last_not_of(_CharT __c, size_type __pos = npos) const noexcept; + + constexpr size_type + find_last_not_of(const _CharT* __str, + size_type __pos, size_type __n) const noexcept; + + constexpr size_type + find_last_not_of(const _CharT* __str, + size_type __pos = npos) const noexcept + { + return this->find_last_not_of(__str, __pos, + traits_type::length(__str)); + } + + constexpr size_type + _M_check(size_type __pos, const char* __s) const noexcept(false) + { + if (__pos > this->size()) + __throw_out_of_range_fmt(__N("%s: __pos (which is %zu) > " + "this->size() (which is %zu)"), + __s, __pos, this->size()); + return __pos; + } + + // NB: _M_limit doesn't check for a bad __pos value. + constexpr size_type + _M_limit(size_type __pos, size_type __off) const noexcept + { + const bool __testoff = __off < this->size() - __pos; + return __testoff ? __off : this->size() - __pos; + } + + private: + + static constexpr int + _S_compare(size_type __n1, size_type __n2) noexcept + { + const difference_type __diff = __n1 - __n2; + if (__diff > std::numeric_limits::max()) + return std::numeric_limits::max(); + if (__diff < std::numeric_limits::min()) + return std::numeric_limits::min(); + return static_cast(__diff); + } + + size_t _M_len; + const _CharT* _M_str; + }; + + // [string.view.comparison], non-member basic_string_view comparison function + + namespace __detail + { + // Identity transform to create a non-deduced context, so that only one + // argument participates in template argument deduction and the other + // argument gets implicitly converted to the deduced type. See n3766.html. + template + using __idt = std::common_type_t<_Tp>; + } + + template + constexpr bool + operator==(basic_string_view<_CharT, _Traits> __x, + basic_string_view<_CharT, _Traits> __y) noexcept + { return __x.size() == __y.size() && __x.compare(__y) == 0; } + + template + constexpr bool + operator==(basic_string_view<_CharT, _Traits> __x, + __detail::__idt> __y) noexcept + { return __x.size() == __y.size() && __x.compare(__y) == 0; } + + template + constexpr bool + operator==(__detail::__idt> __x, + basic_string_view<_CharT, _Traits> __y) noexcept + { return __x.size() == __y.size() && __x.compare(__y) == 0; } + + template + constexpr bool + operator!=(basic_string_view<_CharT, _Traits> __x, + basic_string_view<_CharT, _Traits> __y) noexcept + { return !(__x == __y); } + + template + constexpr bool + operator!=(basic_string_view<_CharT, _Traits> __x, + __detail::__idt> __y) noexcept + { return !(__x == __y); } + + template + constexpr bool + operator!=(__detail::__idt> __x, + basic_string_view<_CharT, _Traits> __y) noexcept + { return !(__x == __y); } + + template + constexpr bool + operator< (basic_string_view<_CharT, _Traits> __x, + basic_string_view<_CharT, _Traits> __y) noexcept + { return __x.compare(__y) < 0; } + + template + constexpr bool + operator< (basic_string_view<_CharT, _Traits> __x, + __detail::__idt> __y) noexcept + { return __x.compare(__y) < 0; } + + template + constexpr bool + operator< (__detail::__idt> __x, + basic_string_view<_CharT, _Traits> __y) noexcept + { return __x.compare(__y) < 0; } + + template + constexpr bool + operator> (basic_string_view<_CharT, _Traits> __x, + basic_string_view<_CharT, _Traits> __y) noexcept + { return __x.compare(__y) > 0; } + + template + constexpr bool + operator> (basic_string_view<_CharT, _Traits> __x, + __detail::__idt> __y) noexcept + { return __x.compare(__y) > 0; } + + template + constexpr bool + operator> (__detail::__idt> __x, + basic_string_view<_CharT, _Traits> __y) noexcept + { return __x.compare(__y) > 0; } + + template + constexpr bool + operator<=(basic_string_view<_CharT, _Traits> __x, + basic_string_view<_CharT, _Traits> __y) noexcept + { return __x.compare(__y) <= 0; } + + template + constexpr bool + operator<=(basic_string_view<_CharT, _Traits> __x, + __detail::__idt> __y) noexcept + { return __x.compare(__y) <= 0; } + + template + constexpr bool + operator<=(__detail::__idt> __x, + basic_string_view<_CharT, _Traits> __y) noexcept + { return __x.compare(__y) <= 0; } + + template + constexpr bool + operator>=(basic_string_view<_CharT, _Traits> __x, + basic_string_view<_CharT, _Traits> __y) noexcept + { return __x.compare(__y) >= 0; } + + template + constexpr bool + operator>=(basic_string_view<_CharT, _Traits> __x, + __detail::__idt> __y) noexcept + { return __x.compare(__y) >= 0; } + + template + constexpr bool + operator>=(__detail::__idt> __x, + basic_string_view<_CharT, _Traits> __y) noexcept + { return __x.compare(__y) >= 0; } + + // [string.view.io], Inserters and extractors + template + inline std::basic_ostream<_CharT, _Traits>& + operator<<(std::basic_ostream<_CharT, _Traits>& __os, + basic_string_view<_CharT,_Traits> __str) + { return __ostream_insert(__os, __str.data(), __str.size()); } + + + // basic_string_view typedef names + + using string_view = basic_string_view; + + // [string.view.hash], hash support: + + template + struct hash; + + template<> + struct hash + : public std::__hash_base + { + size_t + operator()(const string_view& __str) const noexcept + { return std::_Hash_impl::hash(__str.data(), __str.length()); } + }; + + inline namespace literals + { + inline namespace string_view_literals + { +#pragma GCC diagnostic push +#pragma GCC diagnostic ignored "-Wliteral-suffix" + inline constexpr basic_string_view + operator""sv(const char* __str, size_t __len) noexcept + { return basic_string_view{__str, __len}; } +#pragma GCC diagnostic pop + } // namespace string_literals + } // namespace literals + +} /* namespace gdb */ + +#endif /* __cplusplus >= 201703L */ + +#endif /* STRING_VIEW_H */