office-gobmx/include/o3tl/string_view.hxx
Stephan Bergmann db3f072dd6 New o3tl::intcmp.hxx
...introducing o3tl::cmp_equal etc. implementing C++23 std::cmp_equal etc., plus
an o3tl::IntCmp wrapper around it for convenient operator syntax

Change-Id: I1d2e0d1aef99c531039fb83de31ed8e6036fde03
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/135095
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>
2022-05-29 19:38:46 +02:00

487 lines
17 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4; fill-column: 100 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#pragma once
#include <sal/config.h>
#include <cassert>
#include <cstddef>
#include <string>
#include <string_view>
#include <o3tl/intcmp.hxx>
#include <rtl/ustring.h>
#include <rtl/math.h>
namespace o3tl
{
// Like OUString::equalsIgnoreAsciiCase, but for two std::u16string_view:
inline bool equalsAscii(std::u16string_view s1, const char* s2)
{
return rtl_ustr_ascii_compare_WithLength(s1.data(), s1.size(), s2) == 0;
}
// Like OUString::equalsAsciiL
inline bool equalsAscii(std::u16string_view s1, std::string_view s2)
{
return rtl_ustr_ascii_shortenedCompare_WithLength(s1.data(), s1.size(), s2.data(), s2.size())
== 0;
}
// Like OUString::equalsIgnoreAsciiCase, but for two std::u16string_view:
inline bool equalsIgnoreAsciiCase(std::u16string_view s1, std::u16string_view s2)
{
if (s1.size() != s2.size())
return false;
if (s1.data() == s2.data())
return true;
return rtl_ustr_compareIgnoreAsciiCase_WithLength(s1.data(), s1.size(), s2.data(), s2.size())
== 0;
};
inline bool equalsIgnoreAsciiCase(std::string_view s1, std::string_view s2)
{
if (s1.size() != s2.size())
return false;
if (s1.data() == s2.data())
return true;
return rtl_str_compareIgnoreAsciiCase_WithLength(s1.data(), s1.size(), s2.data(), s2.size())
== 0;
};
// Like OUString::compareToIgnoreAsciiCase, but for two std::u16string_view:
inline int compareToIgnoreAsciiCase(std::u16string_view s1, std::u16string_view s2)
{
return rtl_ustr_compareIgnoreAsciiCase_WithLength(s1.data(), s1.size(), s2.data(), s2.size());
};
// Like OUString::matchIgnoreAsciiCase, but for two std::u16string_view:
inline bool matchIgnoreAsciiCase(std::u16string_view s1, std::u16string_view s2,
sal_Int32 fromIndex = 0)
{
return rtl_ustr_shortenedCompareIgnoreAsciiCase_WithLength(
s1.data() + fromIndex, s1.size() - fromIndex, s2.data(), s2.size(), s2.size())
== 0;
}
// Similar to O[U]String::getToken, returning the first token of a std::[u16]string_view starting
// at a given position.
//
// Attention: There are two sets of o3tl::getToken overloads here. This first set has an interface
// based on std::size_t length parameters, and its semantics don't match those of
// O[U]String::getToken exactly (buf if needed, it can be extended to return the n'th token instead
// of just the first, and/or support an initial position of npos, to make the semantics match).
template <typename charT, typename traits = std::char_traits<charT>>
inline std::basic_string_view<charT, traits> getToken(std::basic_string_view<charT, traits> sv,
charT delimiter, std::size_t& position)
{
assert(position <= sv.size());
auto const n = sv.find(delimiter, position);
std::basic_string_view<charT, traits> t;
if (n == std::string_view::npos)
{
t = sv.substr(position);
position = std::string_view::npos;
}
else
{
t = sv.substr(position, n - position);
position = n + 1;
}
return t;
}
// The following two overloads prevent overload resolution mistakes that would occur with their
// template counterpart, when sv is of a type that is implicitly convertible to basic_string_view
// (like OString or OUString), in which case overload resolution would erroneously choose the
// three-argument overloads (taking sv, nToken, cTok) from the second set of
// o3tl::getToken overloads below:
inline std::string_view getToken(std::string_view sv, char delimiter, std::size_t& position)
{
return getToken<char>(sv, delimiter, position);
}
inline std::u16string_view getToken(std::u16string_view sv, char16_t delimiter,
std::size_t& position)
{
return getToken<char16_t>(sv, delimiter, position);
}
// Similar to O[U]String::getToken.
//
// Attention: There are two sets of o3tl::getToken overloads here. This second set has an
// interface based on sal_Int32 length parameters, and is meant to be a drop-in replacement for
// O[U]String::getToken.
template <typename charT, typename traits = std::char_traits<charT>>
inline std::basic_string_view<charT, traits> getToken(std::basic_string_view<charT, traits> pStr,
sal_Int32 nToken, charT cTok,
sal_Int32& rnIndex)
{
assert(o3tl::IntCmp(rnIndex) <= o3tl::IntCmp(pStr.size()));
// Return an empty string and set rnIndex to -1 if either nToken or rnIndex is
// negative:
if (rnIndex >= 0 && nToken >= 0)
{
const charT* pOrgCharStr = pStr.data();
const charT* pCharStr = pOrgCharStr + rnIndex;
sal_Int32 nLen = pStr.size() - rnIndex;
sal_Int32 nTokCount = 0;
const charT* pCharStrStart = pCharStr;
while (nLen > 0)
{
if (*pCharStr == cTok)
{
nTokCount++;
if (nTokCount > nToken)
break;
if (nTokCount == nToken)
pCharStrStart = pCharStr + 1;
}
pCharStr++;
nLen--;
}
if (nTokCount >= nToken)
{
if (nLen > 0)
rnIndex = pCharStr - pOrgCharStr + 1;
else
rnIndex = -1;
return std::basic_string_view<charT, traits>(pCharStrStart, pCharStr - pCharStrStart);
}
}
rnIndex = -1;
return std::basic_string_view<charT, traits>();
}
// The following two overloads prevent deduction failures that would occur with their template
// counterpart, when sv is of a type that is implicitly convertible to basic_string_view (like
// OString or OUString):
inline std::string_view getToken(std::string_view sv, sal_Int32 nToken, char cTok,
sal_Int32& rnIndex)
{
return getToken<char>(sv, nToken, cTok, rnIndex);
}
inline std::u16string_view getToken(std::u16string_view sv, sal_Int32 nToken, char16_t cTok,
sal_Int32& rnIndex)
{
return getToken<char16_t>(sv, nToken, cTok, rnIndex);
}
inline std::string_view getToken(std::string_view sv, sal_Int32 nToken, char cTok)
{
sal_Int32 nIndex = 0;
return getToken<char>(sv, nToken, cTok, nIndex);
}
inline std::u16string_view getToken(std::u16string_view sv, sal_Int32 nToken, char16_t cTok)
{
sal_Int32 nIndex = 0;
return getToken<char16_t>(sv, nToken, cTok, nIndex);
}
// Implementations of C++20 std::basic_string_view::starts_with and
// std::basic_string_view::ends_with, until we can use those directly on all platforms:
template <typename charT, typename traits = std::char_traits<charT>>
constexpr bool starts_with(std::basic_string_view<charT, traits> sv,
std::basic_string_view<charT, traits> x) noexcept
{
#if defined __cpp_lib_starts_ends_with
return sv.starts_with(x);
#else
return sv.substr(0, x.size()) == x;
#endif
}
template <typename charT, typename traits = std::char_traits<charT>>
constexpr bool starts_with(std::basic_string_view<charT, traits> sv, charT x) noexcept
{
#if defined __cpp_lib_starts_ends_with
return sv.starts_with(x);
#else
return !sv.empty() && traits::eq(sv.front(), x);
#endif
}
template <typename charT, typename traits = std::char_traits<charT>>
constexpr bool starts_with(std::basic_string_view<charT, traits> sv, charT const* x)
{
#if defined __cpp_lib_starts_ends_with
return sv.starts_with(x);
#else
return starts_with(sv, std::basic_string_view<charT, traits>(x));
#endif
}
template <typename charT, typename traits = std::char_traits<charT>>
constexpr bool ends_with(std::basic_string_view<charT, traits> sv,
std::basic_string_view<charT, traits> x) noexcept
{
#if defined __cpp_lib_ends_ends_with
return sv.ends_with(x);
#else
return sv.size() >= x.size()
&& sv.compare(sv.size() - x.size(), std::basic_string_view<charT, traits>::npos, x) == 0;
#endif
}
template <typename charT, typename traits = std::char_traits<charT>>
constexpr bool ends_with(std::basic_string_view<charT, traits> sv, charT x) noexcept
{
#if defined __cpp_lib_ends_ends_with
return sv.ends_with(x);
#else
return !sv.empty() && traits::eq(sv.back(), x);
#endif
}
template <typename charT, typename traits = std::char_traits<charT>>
constexpr bool ends_with(std::basic_string_view<charT, traits> sv, charT const* x)
{
#if defined __cpp_lib_ends_ends_with
return sv.ends_with(x);
#else
return ends_with(sv, std::basic_string_view<charT, traits>(x));
#endif
}
// The following overloads prevent deduction failures that would occur with their template
// counterparts, when x is of a type that is implicitly convertible to basic_string_view (like
// OString or OUString, and we only bother to provide overloads for the char and char16_t cases, not
// also for char32_t and wchar_t, nor for C++20 char8_t):
constexpr bool starts_with(std::string_view sv, std::string_view x) noexcept
{
return starts_with<char>(sv, x);
}
constexpr bool starts_with(std::u16string_view sv, std::u16string_view x) noexcept
{
return starts_with<char16_t>(sv, x);
}
constexpr bool ends_with(std::string_view sv, std::string_view x) noexcept
{
return ends_with<char>(sv, x);
}
constexpr bool ends_with(std::u16string_view sv, std::u16string_view x) noexcept
{
return ends_with<char16_t>(sv, x);
}
// Variants of C++20 std::basic_string_view::starts_with and
// std::basic_string_view::ends_with that have a rest out parameter, similar to our OString and
// OUString startsWith and endsWith member functions:
template <typename charT, typename traits = std::char_traits<charT>>
constexpr bool starts_with(std::basic_string_view<charT, traits> sv,
std::basic_string_view<charT, traits> x,
std::basic_string_view<charT, traits>* rest) noexcept
{
assert(rest != nullptr);
auto const found = starts_with(sv, x);
if (found)
{
*rest = sv.substr(x.length());
}
return found;
}
template <typename charT, typename traits = std::char_traits<charT>>
constexpr bool starts_with(std::basic_string_view<charT, traits> sv, charT x,
std::basic_string_view<charT, traits>* rest) noexcept
{
assert(rest != nullptr);
auto const found = starts_with(sv, x);
if (found)
{
*rest = sv.substr(1);
}
return found;
}
template <typename charT, typename traits = std::char_traits<charT>>
constexpr bool starts_with(std::basic_string_view<charT, traits> sv, charT const* x,
std::basic_string_view<charT, traits>* rest)
{
assert(rest != nullptr);
auto const found = starts_with(sv, x);
if (found)
{
*rest = sv.substr(traits::length(x));
}
return found;
}
template <typename charT, typename traits = std::char_traits<charT>>
constexpr bool ends_with(std::basic_string_view<charT, traits> sv,
std::basic_string_view<charT, traits> x,
std::basic_string_view<charT, traits>* rest) noexcept
{
assert(rest != nullptr);
auto const found = ends_with(sv, x);
if (found)
{
*rest = sv.substr(0, sv.length() - x.length());
}
return found;
}
template <typename charT, typename traits = std::char_traits<charT>>
constexpr bool ends_with(std::basic_string_view<charT, traits> sv, charT x,
std::basic_string_view<charT, traits>* rest) noexcept
{
assert(rest != nullptr);
auto const found = ends_with(sv, x);
if (found)
{
*rest = sv.substr(0, sv.length() - 1);
}
return found;
}
template <typename charT, typename traits = std::char_traits<charT>>
constexpr bool ends_with(std::basic_string_view<charT, traits> sv, charT const* x,
std::basic_string_view<charT, traits>* rest)
{
assert(rest != nullptr);
auto const found = ends_with(sv, x);
if (found)
{
*rest = sv.substr(0, sv.length() - traits::length(x));
}
return found;
}
// The following overloads prevent deduction failures that would occur with their template
// counterparts, when x is of a type that is implicitly convertible to basic_string_view (like
// OString or OUString, and we only bother to provide overloads for the char and char16_t cases, not
// also for char32_t and wchar_t, nor for C++20 char8_t):
constexpr bool starts_with(std::string_view sv, std::string_view x, std::string_view* rest) noexcept
{
return starts_with<char>(sv, x, rest);
}
constexpr bool starts_with(std::u16string_view sv, std::u16string_view x,
std::u16string_view* rest) noexcept
{
return starts_with<char16_t>(sv, x, rest);
}
constexpr bool ends_with(std::string_view sv, std::string_view x, std::string_view* rest) noexcept
{
return ends_with<char>(sv, x, rest);
}
constexpr bool ends_with(std::u16string_view sv, std::u16string_view x,
std::u16string_view* rest) noexcept
{
return ends_with<char16_t>(sv, x, rest);
}
namespace internal
{
// copy of implIsWhitespace from sal/rtl/strtmpl.hxx
inline bool implIsWhitespace(sal_Unicode c)
{
/* Space or Control character? */
if ((c <= 32) && c)
return true;
/* Only in the General Punctuation area Space or Control characters are included? */
if ((c < 0x2000) || (c > 0x206F))
return false;
if (((c >= 0x2000) && (c <= 0x200B)) || /* All Spaces */
(c == 0x2028) || /* LINE SEPARATOR */
(c == 0x2029)) /* PARAGRAPH SEPARATOR */
return true;
return false;
}
} // namespace internal
// Like OUString::trim, but for std::u16string_view:
// copy of the trimView code from sal/rtl/strtmpl.hxx
inline std::u16string_view trim(std::u16string_view str)
{
sal_Int32 nLen = str.size();
sal_Int32 nPreSpaces = 0;
sal_Int32 nPostSpaces = 0;
sal_Int32 nIndex = str.size() - 1;
while ((nPreSpaces < nLen) && internal::implIsWhitespace(*(str.data() + nPreSpaces)))
nPreSpaces++;
while ((nIndex > nPreSpaces) && internal::implIsWhitespace(*(str.data() + nIndex)))
{
nPostSpaces++;
nIndex--;
}
return std::u16string_view{ str.data() + nPreSpaces,
static_cast<size_t>(nLen - nPostSpaces - nPreSpaces) };
}
// Like OString::trim, but for std::string_view:
// copy of the trimView code from sal/rtl/strtmpl.hxx
inline std::string_view trim(std::string_view str)
{
sal_Int32 nLen = str.size();
sal_Int32 nPreSpaces = 0;
sal_Int32 nPostSpaces = 0;
sal_Int32 nIndex = str.size() - 1;
while ((nPreSpaces < nLen) && internal::implIsWhitespace(*(str.data() + nPreSpaces)))
nPreSpaces++;
while ((nIndex > nPreSpaces) && internal::implIsWhitespace(*(str.data() + nIndex)))
{
nPostSpaces++;
nIndex--;
}
return std::string_view{ str.data() + nPreSpaces,
static_cast<size_t>(nLen - nPostSpaces - nPreSpaces) };
}
// Like OString::toInt32, but for std::string_view:
inline sal_Int32 toInt32(std::u16string_view str, sal_Int16 radix = 10)
{
sal_Int64 n = rtl_ustr_toInt64_WithLength(str.data(), radix, str.size());
if (n < SAL_MIN_INT32 || n > SAL_MAX_INT32)
n = 0;
return n;
}
inline sal_Int32 toInt32(std::string_view str, sal_Int16 radix = 10)
{
sal_Int64 n = rtl_str_toInt64_WithLength(str.data(), radix, str.size());
if (n < SAL_MIN_INT32 || n > SAL_MAX_INT32)
n = 0;
return n;
}
// Like OString::toUInt32, but for std::string_view:
inline sal_uInt32 toUInt32(std::u16string_view str, sal_Int16 radix = 10)
{
sal_Int64 n = rtl_ustr_toInt64_WithLength(str.data(), radix, str.size());
if (n < 0 || n > SAL_MAX_UINT32)
n = 0;
return n;
}
inline sal_uInt32 toUInt32(std::string_view str, sal_Int16 radix = 10)
{
sal_Int64 n = rtl_str_toInt64_WithLength(str.data(), radix, str.size());
if (n < 0 || n > SAL_MAX_UINT32)
n = 0;
return n;
}
// Like OString::toInt64, but for std::string_view:
inline sal_Int64 toInt64(std::u16string_view str, sal_Int16 radix = 10)
{
return rtl_ustr_toInt64_WithLength(str.data(), radix, str.size());
}
inline sal_Int64 toInt64(std::string_view str, sal_Int16 radix = 10)
{
return rtl_str_toInt64_WithLength(str.data(), radix, str.size());
}
// Like OString::toDouble, but for std::string_view:
inline double toDouble(std::u16string_view str)
{
return rtl_math_uStringToDouble(str.data(), str.data() + str.size(), '.', 0, nullptr, nullptr);
}
inline double toDouble(std::string_view str)
{
return rtl_math_stringToDouble(str.data(), str.data() + str.size(), '.', 0, nullptr, nullptr);
}
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab cinoptions=b1,g0,N-s cinkeys+=0=break: */