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Diffstat (limited to 'src/string_piece.h')
| -rw-r--r-- | src/string_piece.h | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/src/string_piece.h b/src/string_piece.h new file mode 100644 index 0000000..df3562f --- /dev/null +++ b/src/string_piece.h @@ -0,0 +1,224 @@ +// Copyright 2015 Google Inc. All rights reserved +// +// 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. + +// Copyright (c) 2011 The Chromium Authors. All rights reserved. +// Use of this source code is governed by a BSD-style license that can be +// found in the LICENSE file. +// Copied from strings/stringpiece.h with modifications +// +// A string-like object that points to a sized piece of memory. +// +// Functions or methods may use const StringPiece& parameters to accept either +// a "const char*" or a "string" value that will be implicitly converted to +// a StringPiece. The implicit conversion means that it is often appropriate +// to include this .h file in other files rather than forward-declaring +// StringPiece as would be appropriate for most other Google classes. +// +// Systematic usage of StringPiece is encouraged as it will reduce unnecessary +// conversions from "const char*" to "string" and back again. +// + +#ifndef BASE_STRING_PIECE_H_ +#define BASE_STRING_PIECE_H_ +#pragma once + +#include <stddef.h> +#include <string.h> + +#include <string> + +//#include "base/base_api.h" +//#include "base/basictypes.h" + +class StringPiece { + public: + // standard STL container boilerplate + typedef size_t size_type; + typedef char value_type; + typedef const char* pointer; + typedef const char& reference; + typedef const char& const_reference; + typedef ptrdiff_t difference_type; + typedef const char* const_iterator; + typedef const char* iterator; + typedef std::reverse_iterator<const_iterator> const_reverse_iterator; + typedef std::reverse_iterator<iterator> reverse_iterator; + + static const size_type npos; + + public: + // We provide non-explicit singleton constructors so users can pass + // in a "const char*" or a "string" wherever a "StringPiece" is + // expected. + StringPiece() : ptr_(NULL), length_(0) {} + StringPiece(const char* str) + : ptr_(str), length_((str == NULL) ? 0 : strlen(str)) {} + StringPiece(const std::string& str) : ptr_(str.data()), length_(str.size()) {} + StringPiece(const std::string&& str) + : ptr_(str.data()), length_(str.size()) {} + StringPiece(const char* offset, size_type len) : ptr_(offset), length_(len) {} + + // data() may return a pointer to a buffer with embedded NULs, and the + // returned buffer may or may not be null terminated. Therefore it is + // typically a mistake to pass data() to a routine that expects a NUL + // terminated string. + const char* data() const { return ptr_; } + size_type size() const { return length_; } + size_type length() const { return length_; } + bool empty() const { return length_ == 0; } + + void clear() { + ptr_ = NULL; + length_ = 0; + } + void set(const char* data, size_type len) { + ptr_ = data; + length_ = len; + } + void set(const char* str) { + ptr_ = str; + length_ = str ? strlen(str) : 0; + } + void set(const void* data, size_type len) { + ptr_ = reinterpret_cast<const char*>(data); + length_ = len; + } + + char operator[](size_type i) const { return ptr_[i]; } + + void remove_prefix(size_type n) { + ptr_ += n; + length_ -= n; + } + + void remove_suffix(size_type n) { length_ -= n; } + + int compare(const StringPiece& x) const { + int r = + wordmemcmp(ptr_, x.ptr_, (length_ < x.length_ ? length_ : x.length_)); + if (r == 0) { + if (length_ < x.length_) + r = -1; + else if (length_ > x.length_) + r = +1; + } + return r; + } + + std::string as_string() const { + // std::string doesn't like to take a NULL pointer even with a 0 size. + return std::string(!empty() ? data() : "", size()); + } + + void CopyToString(std::string* target) const; + void AppendToString(std::string* target) const; + + // Does "this" start with "x" + bool starts_with(const StringPiece& x) const { + return ((length_ >= x.length_) && + (wordmemcmp(ptr_, x.ptr_, x.length_) == 0)); + } + + // Does "this" end with "x" + bool ends_with(const StringPiece& x) const { + return ((length_ >= x.length_) && + (wordmemcmp(ptr_ + (length_ - x.length_), x.ptr_, x.length_) == 0)); + } + + iterator begin() const { return ptr_; } + iterator end() const { return ptr_ + length_; } + const_reverse_iterator rbegin() const { + return const_reverse_iterator(ptr_ + length_); + } + const_reverse_iterator rend() const { return const_reverse_iterator(ptr_); } + + size_type max_size() const { return length_; } + size_type capacity() const { return length_; } + + size_type copy(char* buf, size_type n, size_type pos = 0) const; + + size_type find(const StringPiece& s, size_type pos = 0) const; + size_type find(char c, size_type pos = 0) const; + size_type rfind(const StringPiece& s, size_type pos = npos) const; + size_type rfind(char c, size_type pos = npos) const; + + size_type find_first_of(const StringPiece& s, size_type pos = 0) const; + size_type find_first_of(char c, size_type pos = 0) const { + return find(c, pos); + } + size_type find_first_not_of(const StringPiece& s, size_type pos = 0) const; + size_type find_first_not_of(char c, size_type pos = 0) const; + size_type find_last_of(const StringPiece& s, size_type pos = npos) const; + size_type find_last_of(char c, size_type pos = npos) const { + return rfind(c, pos); + } + size_type find_last_not_of(const StringPiece& s, size_type pos = npos) const; + size_type find_last_not_of(char c, size_type pos = npos) const; + + StringPiece substr(size_type pos, size_type n = npos) const; + + static int wordmemcmp(const char* p, const char* p2, size_type N) { + return memcmp(p, p2, N); + } + + // kati specific functions will follow. + + char get(size_type i) const { return i < length_ ? ptr_[i] : 0; } + + private: + const char* ptr_; + size_type length_; +}; + +bool operator==(const StringPiece& x, const StringPiece& y); + +inline bool operator!=(const StringPiece& x, const StringPiece& y) { + return !(x == y); +} + +inline bool operator<(const StringPiece& x, const StringPiece& y) { + const int r = StringPiece::wordmemcmp( + x.data(), y.data(), (x.size() < y.size() ? x.size() : y.size())); + return ((r < 0) || ((r == 0) && (x.size() < y.size()))); +} + +inline bool operator>(const StringPiece& x, const StringPiece& y) { + return y < x; +} + +inline bool operator<=(const StringPiece& x, const StringPiece& y) { + return !(x > y); +} + +inline bool operator>=(const StringPiece& x, const StringPiece& y) { + return !(x < y); +} + +namespace std { +template <> +struct hash<StringPiece> { + size_t operator()(const StringPiece& s) const { + size_t result = 0; + for (char c : s) { + result = (result * 131) + c; + } + return result; + } +}; + +} // namespace std + +#define SPF(s) static_cast<int>((s).size()), (s).data() + +#endif // BASE_STRING_PIECE_H_ |