Files
filament/libs/utils/src/CString.cpp
Mathias Agopian 5b71274fa5 get rid of utils::StaticString
In most places this is simply replaced by `std::string_view`.

We also change a few internal/private headers so they accept 
`std::string_view` instead of `utils::CString`.
2022-08-02 09:51:13 -07:00

101 lines
2.8 KiB
C++

/*
* Copyright (C) 2015 The Android Open Source Project
*
* 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
*
* http://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.
*/
#include <utils/CString.h>
#include <utils/compiler.h>
#include <algorithm>
#include <memory>
namespace utils {
UTILS_NOINLINE
CString::CString(const char* cstr, size_t length) {
if (length && cstr) {
Data* p = (Data*)malloc(sizeof(Data) + length + 1);
p->length = (size_type)length;
mCStr = (value_type*)(p + 1);
// we don't use memcpy here to avoid a call to libc, the generated code is pretty good.
std::uninitialized_copy_n(cstr, length, mCStr);
mCStr[length] = '\0';
}
}
CString::CString(size_t length) {
if (length) {
Data* p = (Data*)malloc(sizeof(Data) + length + 1);
p->length = (size_type)length;
mCStr = (value_type*)(p + 1);
std::fill_n(mCStr, length, 0);
mCStr[length] = '\0';
}
}
CString::CString(const char* cstr)
: CString(cstr, size_type(cstr ? strlen(cstr) : 0)) {
}
CString::CString(const CString& rhs)
: CString(rhs.c_str(), rhs.size()) {
}
CString& CString::operator=(const CString& rhs) {
if (this != &rhs) {
auto *const p = mData ? mData - 1 : nullptr;
new(this) CString(rhs);
free(p);
}
return *this;
}
CString& CString::replace(size_type pos, size_type len, const CString& str) noexcept {
assert(pos <= size());
len = std::min(len, size() - pos);
// The new size of the string, after the replacement.
const size_type newSize = size() - len + str.size();
// Allocate enough memory to hold the new string.
Data* p = (Data*) malloc(sizeof(Data) + newSize + 1);
assert(p);
p->length = newSize;
value_type* newStr = (value_type*) (p + 1);
const value_type* beginning = mCStr;
const value_type* replacementStart = mCStr + pos;
const value_type* replacementEnd = replacementStart + len;
const value_type* end = beginning + size();
value_type* ptr = newStr;
ptr = std::uninitialized_copy(beginning, replacementStart, ptr);
ptr = std::uninitialized_copy_n(str.c_str_safe(), str.length(), ptr);
ptr = std::uninitialized_copy(replacementEnd, end, ptr);
// null-terminator
*ptr = 0;
std::swap(mCStr, newStr);
if (newStr) {
free((Data*) newStr - 1);
}
return *this;
}
} // namespace utils