include/string - platform/external/astl - Git at Google

 /* -*- c++ -*- */
 /*
  * Copyright (C) 2009 The Android Open Source Project
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *  * Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  *  * Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in
  *    the documentation and/or other materials provided with the
  *    distribution.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */

 #ifndef ANDROID_ASTL_STRING__
 #define ANDROID_ASTL_STRING__

 #include <cstddef>

 namespace std {

 // Simple string implementation. Its purpose is to be able to compile code that
 // uses the STL and requires std::string.
 //
 // IMPORTANT:
 // . This class it is not fully STL compliant. Some constructors/methods maybe
 // missing, they will be added on demand.
 // . We don't provide a std::basic_string template that std::string extends
 // because we use only char (wchar is not supported on Android).
 // . The memory allocation scheme uses the heap. Since Android has the concept
 // of SharedBuffer, we may, in the future, templatize this class and add an
 // allocation parameter.
 // . The implementation is not optimized in any way (no copy on write support),
 // temporary instance may be expensive.
 // . Currently there is no support for iterators.
 //

 class string
 {
   public:
     typedef size_t size_type;
     typedef char   value_type;

     static const size_type npos = static_cast<size_type>(-1);

     // Constructors
     string();

     string(const string& str);

     // Construct a string from a source's substring.
     // @param str The source string.
     // @param pos The index of the character to start the copy at.
     // @param n The number of characters to copy. Use string::npos for the
     // remainder.
     string(const string& str, size_t pos, size_type n);

     // Same as above but implicitly copy from pos to the end of the str.
     string(const string& str, size_type pos);

     // Construct a string from a C string.
     // @param str The source string, must be '\0' terminated.
     string(const value_type *str);

     // Construct a string from a char array.
     // @param str The source C string. '\0' are ignored.
     // @param n The number of characters to copy.
     string(const value_type *str, size_type n);

     // Construct a string from a repetition of a character.
     // @param n The number of characters.
     // @param c The character to use.
     string(size_t n, char c);

     // Construct a string from a char array.
     // @param begin The start of the source C string. '\0' are ignored.
     // @param end The end of source C string. Points just pass the last
     // character.
     string(const value_type *begin, const value_type *end);

     ~string();

     // @return The number of characters in the string, not including any
     // null-termination.
     size_type length() const { return mLength; }
     size_type size() const { return mLength; }

     // @return A pointer to null-terminated contents.
     const value_type *c_str() const { return mData; }
     const value_type *data() const { return mData; }

     // Empty the string on return. Release the internal buffer. Length
     // and capacity are both 0 on return. If you want to keep the
     // internal buffer around for reuse, call 'erase' instead.
     void clear();

     // @return true if the string is empty.
     bool empty() const { return this->size() == 0; }

     // Remove 'len' characters from the string starting at 'pos'. The
     // string length is reduced by 'len'. If len is greater or equal
     // to the number of characters in the string, it is truncated at
     // 'pos'. If 'pos' is beyond the end of the string, 'erase' does
     // nothing. Note, regular STL implementations throw a out_of_range
     // exception in this case.
     // Internally, the capacity of the buffer remains unchanged. If
     // you wanted to recover the deleted chars' memory you should call
     // 'reserve' explicitly (see also 'clear').
     // @param pos Index of the first character to remove (default to 0)
     // @param n Number of characters to delete. (default to remainder)
     // @return a reference to this string.
     string& erase(size_type pos = 0, size_type n = npos);

     // @param str The string to be append.
     // @return A reference to this string.
     string& operator+=(const string& str) { return this->append(str); }

     // @param str The C string to be append.
     // @return A reference to this string.
     string& operator+=(const value_type *str) { return this->append(str); }

     // @param c A character to be append.
     // @return A reference to this string.
     string& operator+=(const char c) { this->push_back(c); return *this; }

     // @param c A character to be append.
     void push_back(const char c);

     // no-op if str is NULL.
     string& append(const value_type *str);
     // no-op if str is NULL. n must be >= 0.
     string& append(const value_type *str, size_type n);
     // no-op if str is NULL. pos and n must be >= 0.
     string& append(const value_type *str, size_type pos, size_type n);
     string& append(const string& str);

     // Comparison.
     // @return 0 if this==other, < 0 if this < other and > 0 if this > other.
     // Don't assume the values are -1, 0, 1
     int compare(const string& other) const;
     int compare(const value_type *other) const;

     friend bool operator==(const string& left, const string& right);
     friend bool operator==(const string& left, const value_type *right);
     friend bool operator==(const value_type *left, const string& right) { return right == left; }
     friend bool operator!=(const string& left, const string& right) { return !(left == right); }
     friend bool operator!=(const string& left, const char* right) { return !(left == right); }
     friend bool operator!=(const value_type *left, const string& right) { return !(left == right); }

     // @return Number of elements for which memory has been allocated. capacity >= size().
     size_type capacity() const { return mCapacity; }

     // Change the capacity to new_size. No effect if new_size < size().
     // 0 means Shrink to fit.
     // @param new_size number of character to be allocated.
     void reserve(size_type new_size = 0);

     // Exchange the content of this with the content of other.
     // @param other Instance to swap this one with.
     void swap(string& other);

     // Accessors.
     // @param pos of the char. No boundary, signed checks are done.
     // @return a const reference to the char.
     const char& operator[](const size_type pos) const;

     // @param pos of the char. No boundary, signed checks are done.
     // @return a reference to the char.
     char& operator[](const size_type pos);

     // Assignments.
     string& operator=(const string& str) { return assign(str); }
     string& operator=(const char* str) { return assign(str); }
     string& operator=(char c);

     string& assign(const string& str);
     // Assign a substring of the original.
     // @param str Original string.
     // @param pos Index of the start of the copy.
     // @param n Number of character to be copied.
     string& assign(const string& str, size_type pos, size_type n);
     string& assign(const value_type *str);

     // Assign a non-nul terminated array of chars.
     // @param array Of chars non-nul terminated.
     // @param len Length of the array.
     string& assign(const value_type *array, size_type len);

     // Concat. Prefer using += or append.
     // Uses unnamed object for return value optimization.
     friend string operator+(const string& left, const string& right) {
         return string(left).append(right);
     }
     friend string operator+(const string& left, const value_type *right) {
         return string(left).append(right);
     }
     friend string operator+(const value_type *left, const string& right) {
         return string(left).append(right);
     }
     friend string operator+(const string& left, char right) {
         return string(left).operator+=(right);
     }
     friend string operator+(char left, const string& right) {
         return string(&left, 1).append(right);
     }

     // Find the position of a sub-string. The empty string is always
     // found at the requested position except when it's beyond the
     // string's end.
     // @param str String to locate.
     // @param pos Index of the character to search from. Default to 0.
     // @return Index of start of the first occurrence of the
     // string. string::npos if no occurrence of str was found from the
     // starting position.
     size_type find(const string& str, size_type pos = 0) const {
         return find(str.mData, pos);
     }

     // Find the position of a C sub-string. The empty string is always
     // found at the requested position except when it's beyond the
     // string's end.
     // @param str C string to locate.
     // @param pos Index of the character to search from. Default to 0.
     // @return Index of start of the first occurrence of the
     // string. string::npos if no occurrence of str was found from the
     // starting position.
     size_type find(const value_type *str, size_type pos = 0) const;

   private:
     bool SafeMalloc(size_type n);
     void SafeRealloc(size_type n);
     void SafeFree(value_type *str);
     void ResetTo(value_type *str);
     void ConstructEmptyString();
     void Constructor(const value_type *str, size_type n);
     void Constructor(const value_type *str, size_type pos, size_type n);
     void Constructor(size_type num, char c);
     void DeleteSafe();
     void Append(const value_type *str, size_type len);

     value_type *mData;  // pointer to the buffer
     size_type mCapacity;  // size of the buffer.
     size_type mLength;  // len of the string excl. null-terminator.
 };

 }  // namespace std

 #endif  // ANDROID_ASTL_STRING__
	/* -- c++ -- */
	/*
	* Copyright (C) 2009 The Android Open Source Project
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* * Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* * Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in
	* the documentation and/or other materials provided with the
	* distribution.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
	* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
	* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
	* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
	* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
	* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
	* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	* SUCH DAMAGE.
	*/

	#ifndef ANDROID_ASTL_STRING__
	#define ANDROID_ASTL_STRING__

	#include <cstddef>

	namespace std {

	// Simple string implementation. Its purpose is to be able to compile code that
	// uses the STL and requires std::string.
	//
	// IMPORTANT:
	// . This class it is not fully STL compliant. Some constructors/methods maybe
	// missing, they will be added on demand.
	// . We don't provide a std::basic_string template that std::string extends
	// because we use only char (wchar is not supported on Android).
	// . The memory allocation scheme uses the heap. Since Android has the concept
	// of SharedBuffer, we may, in the future, templatize this class and add an
	// allocation parameter.
	// . The implementation is not optimized in any way (no copy on write support),
	// temporary instance may be expensive.
	// . Currently there is no support for iterators.
	//

	class string
	{
	public:
	typedef size_t size_type;
	typedef char value_type;

	static const size_type npos = static_cast<size_type>(-1);

	// Constructors
	string();

	string(const string& str);

	// Construct a string from a source's substring.
	// @param str The source string.
	// @param pos The index of the character to start the copy at.
	// @param n The number of characters to copy. Use string::npos for the
	// remainder.
	string(const string& str, size_t pos, size_type n);

	// Same as above but implicitly copy from pos to the end of the str.
	string(const string& str, size_type pos);

	// Construct a string from a C string.
	// @param str The source string, must be '\0' terminated.
	string(const value_type *str);

	// Construct a string from a char array.
	// @param str The source C string. '\0' are ignored.
	// @param n The number of characters to copy.
	string(const value_type *str, size_type n);

	// Construct a string from a repetition of a character.
	// @param n The number of characters.
	// @param c The character to use.
	string(size_t n, char c);

	// Construct a string from a char array.
	// @param begin The start of the source C string. '\0' are ignored.
	// @param end The end of source C string. Points just pass the last
	// character.
	string(const value_type begin, const value_type end);

	~string();

	// @return The number of characters in the string, not including any
	// null-termination.
	size_type length() const { return mLength; }
	size_type size() const { return mLength; }

	// @return A pointer to null-terminated contents.
	const value_type *c_str() const { return mData; }
	const value_type *data() const { return mData; }

	// Empty the string on return. Release the internal buffer. Length
	// and capacity are both 0 on return. If you want to keep the
	// internal buffer around for reuse, call 'erase' instead.
	void clear();

	// @return true if the string is empty.
	bool empty() const { return this->size() == 0; }

	// Remove 'len' characters from the string starting at 'pos'. The
	// string length is reduced by 'len'. If len is greater or equal
	// to the number of characters in the string, it is truncated at
	// 'pos'. If 'pos' is beyond the end of the string, 'erase' does
	// nothing. Note, regular STL implementations throw a out_of_range
	// exception in this case.
	// Internally, the capacity of the buffer remains unchanged. If
	// you wanted to recover the deleted chars' memory you should call
	// 'reserve' explicitly (see also 'clear').
	// @param pos Index of the first character to remove (default to 0)
	// @param n Number of characters to delete. (default to remainder)
	// @return a reference to this string.
	string& erase(size_type pos = 0, size_type n = npos);

	// @param str The string to be append.
	// @return A reference to this string.
	string& operator+=(const string& str) { return this->append(str); }

	// @param str The C string to be append.
	// @return A reference to this string.
	string& operator+=(const value_type *str) { return this->append(str); }

	// @param c A character to be append.
	// @return A reference to this string.
	string& operator+=(const char c) { this->push_back(c); return *this; }

	// @param c A character to be append.
	void push_back(const char c);

	// no-op if str is NULL.
	string& append(const value_type *str);
	// no-op if str is NULL. n must be >= 0.
	string& append(const value_type *str, size_type n);
	// no-op if str is NULL. pos and n must be >= 0.
	string& append(const value_type *str, size_type pos, size_type n);
	string& append(const string& str);

	// Comparison.
	// @return 0 if this==other, < 0 if this < other and > 0 if this > other.
	// Don't assume the values are -1, 0, 1
	int compare(const string& other) const;
	int compare(const value_type *other) const;

	friend bool operator==(const string& left, const string& right);
	friend bool operator==(const string& left, const value_type *right);
	friend bool operator==(const value_type *left, const string& right) { return right == left; }
	friend bool operator!=(const string& left, const string& right) { return !(left == right); }
	friend bool operator!=(const string& left, const char* right) { return !(left == right); }
	friend bool operator!=(const value_type *left, const string& right) { return !(left == right); }

	// @return Number of elements for which memory has been allocated. capacity >= size().
	size_type capacity() const { return mCapacity; }

	// Change the capacity to new_size. No effect if new_size < size().
	// 0 means Shrink to fit.
	// @param new_size number of character to be allocated.
	void reserve(size_type new_size = 0);

	// Exchange the content of this with the content of other.
	// @param other Instance to swap this one with.
	void swap(string& other);

	// Accessors.
	// @param pos of the char. No boundary, signed checks are done.
	// @return a const reference to the char.
	const char& operator[](const size_type pos) const;

	// @param pos of the char. No boundary, signed checks are done.
	// @return a reference to the char.
	char& operator[](const size_type pos);

	// Assignments.
	string& operator=(const string& str) { return assign(str); }
	string& operator=(const char* str) { return assign(str); }
	string& operator=(char c);

	string& assign(const string& str);
	// Assign a substring of the original.
	// @param str Original string.
	// @param pos Index of the start of the copy.
	// @param n Number of character to be copied.
	string& assign(const string& str, size_type pos, size_type n);
	string& assign(const value_type *str);

	// Assign a non-nul terminated array of chars.
	// @param array Of chars non-nul terminated.
	// @param len Length of the array.
	string& assign(const value_type *array, size_type len);

	// Concat. Prefer using += or append.
	// Uses unnamed object for return value optimization.
	friend string operator+(const string& left, const string& right) {
	return string(left).append(right);
	}
	friend string operator+(const string& left, const value_type *right) {
	return string(left).append(right);
	}
	friend string operator+(const value_type *left, const string& right) {
	return string(left).append(right);
	}
	friend string operator+(const string& left, char right) {
	return string(left).operator+=(right);
	}
	friend string operator+(char left, const string& right) {
	return string(&left, 1).append(right);
	}

	// Find the position of a sub-string. The empty string is always
	// found at the requested position except when it's beyond the
	// string's end.
	// @param str String to locate.
	// @param pos Index of the character to search from. Default to 0.
	// @return Index of start of the first occurrence of the
	// string. string::npos if no occurrence of str was found from the
	// starting position.
	size_type find(const string& str, size_type pos = 0) const {
	return find(str.mData, pos);
	}

	// Find the position of a C sub-string. The empty string is always
	// found at the requested position except when it's beyond the
	// string's end.
	// @param str C string to locate.
	// @param pos Index of the character to search from. Default to 0.
	// @return Index of start of the first occurrence of the
	// string. string::npos if no occurrence of str was found from the
	// starting position.
	size_type find(const value_type *str, size_type pos = 0) const;

	private:
	bool SafeMalloc(size_type n);
	void SafeRealloc(size_type n);
	void SafeFree(value_type *str);
	void ResetTo(value_type *str);
	void ConstructEmptyString();
	void Constructor(const value_type *str, size_type n);
	void Constructor(const value_type *str, size_type pos, size_type n);
	void Constructor(size_type num, char c);
	void DeleteSafe();
	void Append(const value_type *str, size_type len);

	value_type *mData; // pointer to the buffer
	size_type mCapacity; // size of the buffer.
	size_type mLength; // len of the string excl. null-terminator.
	};

	} // namespace std

	#endif // ANDROID_ASTL_STRING__