gecko/xpcom/string/public/nsTSubstring.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 sts=2 et cindent: */
/* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0/LGPL 2.1
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (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.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Mozilla.
*
* The Initial Developer of the Original Code is IBM Corporation.
* Portions created by IBM Corporation are Copyright (C) 2003
* IBM Corporation. All Rights Reserved.
*
* Contributor(s):
* Darin Fisher <darin@meer.net>
*
* Alternatively, the contents of this file may be used under the terms of
* either the GNU General Public License Version 2 or later (the "GPL"), or
* the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
* in which case the provisions of the GPL or the LGPL are applicable instead
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#ifndef MOZILLA_INTERNAL_API
#error Cannot use internal string classes without MOZILLA_INTERNAL_API defined. Use the frozen header nsStringAPI.h instead.
#endif
/**
* The base for string comparators
*/
class NS_COM nsTStringComparator_CharT
{
public:
typedef CharT char_type;
nsTStringComparator_CharT() {}
virtual int operator()( const char_type*, const char_type*, PRUint32 length ) const = 0;
virtual int operator()( char_type, char_type ) const = 0;
};
/**
* The default string comparator (case-sensitive comparision)
*/
class NS_COM nsTDefaultStringComparator_CharT
: public nsTStringComparator_CharT
{
public:
typedef CharT char_type;
nsTDefaultStringComparator_CharT() {}
virtual int operator()( const char_type*, const char_type*, PRUint32 length ) const;
virtual int operator()( char_type, char_type ) const;
};
/**
* nsTSubstring is the most abstract class in the string hierarchy. It
* represents a single contiguous array of characters, which may or may not
* be null-terminated. This type is not instantiated directly. A sub-class
* is instantiated instead. For example, see nsTString.
*
* NAMES:
* nsAString for wide characters
* nsACString for narrow characters
*
* Many of the accessors on nsTSubstring are inlined as an optimization.
*/
class nsTSubstring_CharT
{
public:
typedef CharT char_type;
typedef nsCharTraits<char_type> char_traits;
typedef char_traits::incompatible_char_type incompatible_char_type;
typedef nsTSubstring_CharT self_type;
typedef self_type abstract_string_type;
typedef self_type base_string_type;
typedef self_type substring_type;
typedef nsTSubstringTuple_CharT substring_tuple_type;
typedef nsTString_CharT string_type;
typedef nsReadingIterator<char_type> const_iterator;
typedef nsWritingIterator<char_type> iterator;
typedef nsTStringComparator_CharT comparator_type;
typedef char_type* char_iterator;
typedef const char_type* const_char_iterator;
typedef PRUint32 size_type;
typedef PRUint32 index_type;
public:
// this acts like a virtual destructor
NS_COM NS_CONSTRUCTOR_FASTCALL ~nsTSubstring_CharT();
/**
* reading iterators
*/
const_char_iterator BeginReading() const { return mData; }
const_char_iterator EndReading() const { return mData + mLength; }
/**
* deprecated reading iterators
*/
const_iterator& BeginReading( const_iterator& iter ) const
{
iter.mStart = mData;
iter.mEnd = mData + mLength;
iter.mPosition = iter.mStart;
return iter;
}
const_iterator& EndReading( const_iterator& iter ) const
{
iter.mStart = mData;
iter.mEnd = mData + mLength;
iter.mPosition = iter.mEnd;
return iter;
}
const_char_iterator& BeginReading( const_char_iterator& iter ) const
{
return iter = mData;
}
const_char_iterator& EndReading( const_char_iterator& iter ) const
{
return iter = mData + mLength;
}
/**
* writing iterators
*/
char_iterator BeginWriting()
{
return EnsureMutable() ? mData : char_iterator(0);
}
char_iterator EndWriting()
{
return EnsureMutable() ? (mData + mLength) : char_iterator(0);
}
/**
* deprecated writing iterators
*/
iterator& BeginWriting( iterator& iter )
{
char_type *data = EnsureMutable() ? mData : nsnull;
iter.mStart = data;
iter.mEnd = data + mLength;
iter.mPosition = iter.mStart;
return iter;
}
iterator& EndWriting( iterator& iter )
{
char_type *data = EnsureMutable() ? mData : nsnull;
iter.mStart = data;
iter.mEnd = data + mLength;
iter.mPosition = iter.mEnd;
return iter;
}
char_iterator& BeginWriting( char_iterator& iter )
{
return iter = EnsureMutable() ? mData : char_iterator(0);
}
char_iterator& EndWriting( char_iterator& iter )
{
return iter = EnsureMutable() ? (mData + mLength) : char_iterator(0);
}
/**
* accessors
*/
// returns pointer to string data (not necessarily null-terminated)
const char_type *Data() const
{
return mData;
}
size_type Length() const
{
return mLength;
}
PRBool IsEmpty() const
{
return mLength == 0;
}
PRBool IsVoid() const
{
return (mFlags & F_VOIDED) != 0;
}
PRBool IsTerminated() const
{
return (mFlags & F_TERMINATED) != 0;
}
char_type CharAt( index_type i ) const
{
NS_ASSERTION(i < mLength, "index exceeds allowable range");
return mData[i];
}
char_type operator[]( index_type i ) const
{
return CharAt(i);
}
char_type First() const
{
NS_ASSERTION(mLength > 0, "|First()| called on an empty string");
return mData[0];
}
inline
char_type Last() const
{
NS_ASSERTION(mLength > 0, "|Last()| called on an empty string");
return mData[mLength - 1];
}
NS_COM size_type NS_FASTCALL CountChar( char_type ) const;
NS_COM PRInt32 NS_FASTCALL FindChar( char_type, index_type offset = 0 ) const;
/**
* equality
*/
NS_COM PRBool NS_FASTCALL Equals( const self_type& ) const;
NS_COM PRBool NS_FASTCALL Equals( const self_type&, const comparator_type& ) const;
NS_COM PRBool NS_FASTCALL Equals( const char_type* data ) const;
NS_COM PRBool NS_FASTCALL Equals( const char_type* data, const comparator_type& comp ) const;
/**
* An efficient comparison with ASCII that can be used even
* for wide strings. Call this version when you know the
* length of 'data'.
*/
NS_COM PRBool NS_FASTCALL EqualsASCII( const char* data, size_type len ) const;
/**
* An efficient comparison with ASCII that can be used even
* for wide strings. Call this version when 'data' is
* null-terminated.
*/
NS_COM PRBool NS_FASTCALL EqualsASCII( const char* data ) const;
// EqualsLiteral must ONLY be applied to an actual literal string.
// Do not attempt to use it with a regular char* pointer, or with a char
// array variable.
// The template trick to acquire the array length at compile time without
// using a macro is due to Corey Kosak, with much thanks.
#ifdef NS_DISABLE_LITERAL_TEMPLATE
inline PRBool EqualsLiteral( const char* str ) const
{
return EqualsASCII(str);
}
#else
template<int N>
inline PRBool EqualsLiteral( const char (&str)[N] ) const
{
return EqualsASCII(str, N-1);
}
template<int N>
inline PRBool EqualsLiteral( char (&str)[N] ) const
{
const char* s = str;
return EqualsASCII(s, N-1);
}
#endif
// The LowerCaseEquals methods compare the lower case version of
// this string to some ASCII/Literal string. The ASCII string is
// *not* lowercased for you. If you compare to an ASCII or literal
// string that contains an uppercase character, it is guaranteed to
// return false. We will throw assertions too.
NS_COM PRBool NS_FASTCALL LowerCaseEqualsASCII( const char* data, size_type len ) const;
NS_COM PRBool NS_FASTCALL LowerCaseEqualsASCII( const char* data ) const;
// LowerCaseEqualsLiteral must ONLY be applied to an actual
// literal string. Do not attempt to use it with a regular char*
// pointer, or with a char array variable. Use
// LowerCaseEqualsASCII for them.
#ifdef NS_DISABLE_LITERAL_TEMPLATE
inline PRBool LowerCaseEqualsLiteral( const char* str ) const
{
return LowerCaseEqualsASCII(str);
}
#else
template<int N>
inline PRBool LowerCaseEqualsLiteral( const char (&str)[N] ) const
{
return LowerCaseEqualsASCII(str, N-1);
}
template<int N>
inline PRBool LowerCaseEqualsLiteral( char (&str)[N] ) const
{
const char* s = str;
return LowerCaseEqualsASCII(s, N-1);
}
#endif
/**
* assignment
*/
NS_COM void NS_FASTCALL Assign( char_type c );
NS_COM void NS_FASTCALL Assign( const char_type* data, size_type length = size_type(-1) );
NS_COM void NS_FASTCALL Assign( const self_type& );
NS_COM void NS_FASTCALL Assign( const substring_tuple_type& );
NS_COM void NS_FASTCALL AssignASCII( const char* data, size_type length );
NS_COM void NS_FASTCALL AssignASCII( const char* data );
// AssignLiteral must ONLY be applied to an actual literal string.
// Do not attempt to use it with a regular char* pointer, or with a char
// array variable. Use AssignASCII for those.
#ifdef NS_DISABLE_LITERAL_TEMPLATE
void AssignLiteral( const char* str )
{ AssignASCII(str); }
#else
template<int N>
void AssignLiteral( const char (&str)[N] )
{ AssignASCII(str, N-1); }
template<int N>
void AssignLiteral( char (&str)[N] )
{ AssignASCII(str, N-1); }
#endif
self_type& operator=( char_type c ) { Assign(c); return *this; }
self_type& operator=( const char_type* data ) { Assign(data); return *this; }
self_type& operator=( const self_type& str ) { Assign(str); return *this; }
self_type& operator=( const substring_tuple_type& tuple ) { Assign(tuple); return *this; }
NS_COM void NS_FASTCALL Adopt( char_type* data, size_type length = size_type(-1) );
/**
* buffer manipulation
*/
NS_COM void NS_FASTCALL Replace( index_type cutStart, size_type cutLength, char_type c );
NS_COM void NS_FASTCALL Replace( index_type cutStart, size_type cutLength, const char_type* data, size_type length = size_type(-1) );
void Replace( index_type cutStart, size_type cutLength, const self_type& str ) { Replace(cutStart, cutLength, str.Data(), str.Length()); }
NS_COM void NS_FASTCALL Replace( index_type cutStart, size_type cutLength, const substring_tuple_type& tuple );
NS_COM void NS_FASTCALL ReplaceASCII( index_type cutStart, size_type cutLength, const char* data, size_type length = size_type(-1) );
void Append( char_type c ) { Replace(mLength, 0, c); }
void Append( const char_type* data, size_type length = size_type(-1) ) { Replace(mLength, 0, data, length); }
void Append( const self_type& str ) { Replace(mLength, 0, str); }
void Append( const substring_tuple_type& tuple ) { Replace(mLength, 0, tuple); }
void AppendASCII( const char* data, size_type length = size_type(-1) ) { ReplaceASCII(mLength, 0, data, length); }
// AppendPrintf truncates output to 31 ASCII characters
NS_COM void AppendPrintf( const char* format, ... );
void AppendInt( PRInt32 aInteger )
{ AppendPrintf( "%d", aInteger ); }
void AppendInt( PRInt32 aInteger, int aRadix )
{
const char *fmt = aRadix == 10 ? "%d" : aRadix == 8 ? "%o" : "%x";
AppendPrintf( fmt, aInteger );
}
void AppendInt( PRUint32 aInteger )
{ AppendPrintf( "%u", aInteger ); }
void AppendInt( PRUint32 aInteger, int aRadix )
{
const char *fmt = aRadix == 10 ? "%u" : aRadix == 8 ? "%o" : "%x";
AppendPrintf( fmt, aInteger );
}
void AppendInt( PRInt64 aInteger )
{ AppendPrintf( "%lld", aInteger ); }
void AppendInt( PRInt64 aInteger, int aRadix )
{
const char *fmt = aRadix == 10 ? "%lld" : aRadix == 8 ? "%llo" : "%llx";
AppendPrintf( fmt, aInteger );
}
void AppendInt( PRUint64 aInteger )
{ AppendPrintf( "%llu", aInteger ); }
void AppendInt( PRUint64 aInteger, int aRadix )
{
const char *fmt = aRadix == 10 ? "%llu" : aRadix == 8 ? "%llo" : "%llx";
AppendPrintf( fmt, aInteger );
}
// AppendLiteral must ONLY be applied to an actual literal string.
// Do not attempt to use it with a regular char* pointer, or with a char
// array variable. Use AppendASCII for those.
#ifdef NS_DISABLE_LITERAL_TEMPLATE
void AppendLiteral( const char* str )
{ AppendASCII(str); }
#else
template<int N>
void AppendLiteral( const char (&str)[N] )
{ AppendASCII(str, N-1); }
template<int N>
void AppendLiteral( char (&str)[N] )
{ AppendASCII(str, N-1); }
#endif
self_type& operator+=( char_type c ) { Append(c); return *this; }
self_type& operator+=( const char_type* data ) { Append(data); return *this; }
self_type& operator+=( const self_type& str ) { Append(str); return *this; }
self_type& operator+=( const substring_tuple_type& tuple ) { Append(tuple); return *this; }
void Insert( char_type c, index_type pos ) { Replace(pos, 0, c); }
void Insert( const char_type* data, index_type pos, size_type length = size_type(-1) ) { Replace(pos, 0, data, length); }
void Insert( const self_type& str, index_type pos ) { Replace(pos, 0, str); }
void Insert( const substring_tuple_type& tuple, index_type pos ) { Replace(pos, 0, tuple); }
void Cut( index_type cutStart, size_type cutLength ) { Replace(cutStart, cutLength, char_traits::sEmptyBuffer, 0); }
/**
* buffer sizing
*/
/**
* Attempts to set the capacity to the given size, without affecting
* the length of the string. Also ensures that the buffer is mutable.
*
* @returns PR_TRUE on success
* PR_FALSE on out-of-memory, or if requesting a size bigger
* than a string can hold (2^31 chars).
*/
NS_COM PRBool NS_FASTCALL SetCapacity( size_type newCapacity );
NS_COM void NS_FASTCALL SetLength( size_type newLength );
void Truncate( size_type newLength = 0 )
{
NS_ASSERTION(newLength <= mLength, "Truncate cannot make string longer");
SetLength(newLength);
}
/**
* buffer access
*/
/**
* Get a const pointer to the string's internal buffer. The caller
* MUST NOT modify the characters at the returned address.
*
* @returns The length of the buffer in characters.
*/
inline size_type GetData( const char_type** data ) const
{
*data = mData;
return mLength;
}
/**
* Get a pointer to the string's internal buffer, optionally resizing
* the buffer first. If size_type(-1) is passed for newLen, then the
* current length of the string is used. The caller MAY modify the
* characters at the returned address (up to but not exceeding the
* length of the string).
*
* @returns The length of the buffer in characters or 0 if unable to
* satisfy the request due to low-memory conditions.
*/
inline size_type GetMutableData( char_type** data, size_type newLen = size_type(-1) )
{
if (!EnsureMutable(newLen))
{
*data = nsnull;
return 0;
}
*data = mData;
return mLength;
}
/**
* string data is never null, but can be marked void. if true, the
* string will be truncated. @see nsTSubstring::IsVoid
*/
NS_COM void NS_FASTCALL SetIsVoid( PRBool );
/**
* This method is used to remove all occurrences of aChar from this
* string.
*
* @param aChar -- char to be stripped
* @param aOffset -- where in this string to start stripping chars
*/
NS_COM void StripChar( char_type aChar, PRInt32 aOffset=0 );
public:
/**
* this is public to support automatic conversion of tuple to string
* base type, which helps avoid converting to nsTAString.
*/
NS_COM nsTSubstring_CharT(const substring_tuple_type& tuple);
/**
* allows for direct initialization of a nsTSubstring object.
*
* NOTE: this constructor is declared public _only_ for convenience
* inside the string implementation.
*/
#ifdef XP_OS2 /* Workaround for GCC 3.3.x bug. */
nsTSubstring_CharT( char_type *data, size_type length, PRUint32 flags ) NS_COM;
#else
NS_COM nsTSubstring_CharT( char_type *data, size_type length, PRUint32 flags );
#endif
protected:
friend class nsTObsoleteAStringThunk_CharT;
friend class nsTSubstringTuple_CharT;
// XXX GCC 3.4 needs this :-(
friend class nsTPromiseFlatString_CharT;
char_type* mData;
size_type mLength;
PRUint32 mFlags;
// default initialization
NS_COM nsTSubstring_CharT();
// version of constructor that leaves mData and mLength uninitialized
explicit
NS_COM nsTSubstring_CharT( PRUint32 flags );
// copy-constructor, constructs as dependent on given object
// (NOTE: this is for internal use only)
NS_COM nsTSubstring_CharT( const self_type& str );
/**
* this function releases mData and does not change the value of
* any of its member variables. in other words, this function acts
* like a destructor.
*/
void NS_FASTCALL Finalize();
/**
* this function prepares mData to be mutated.
*
* @param capacity specifies the required capacity of mData
* @param old_data returns null or the old value of mData
* @param old_flags returns 0 or the old value of mFlags
*
* if mData is already mutable and of sufficient capacity, then this
* function will return immediately. otherwise, it will either resize
* mData or allocate a new shared buffer. if it needs to allocate a
* new buffer, then it will return the old buffer and the corresponding
* flags. this allows the caller to decide when to free the old data.
*
* this function returns false if is unable to allocate sufficient
* memory.
*
* XXX we should expose a way for subclasses to free old_data.
*/
PRBool NS_FASTCALL MutatePrep( size_type capacity, char_type** old_data, PRUint32* old_flags );
/**
* this function prepares a section of mData to be modified. if
* necessary, this function will reallocate mData and possibly move
* existing data to open up the specified section.
*
* @param cutStart specifies the starting offset of the section
* @param cutLength specifies the length of the section to be replaced
* @param newLength specifies the length of the new section
*
* for example, suppose mData contains the string "abcdef" then
*
* ReplacePrep(2, 3, 4);
*
* would cause mData to look like "ab____f" where the characters
* indicated by '_' have an unspecified value and can be freely
* modified. this function will null-terminate mData upon return.
*
* this function returns false if is unable to allocate sufficient
* memory.
*/
PRBool NS_FASTCALL ReplacePrep( index_type cutStart, size_type cutLength, size_type newLength );
/**
* returns the number of writable storage units starting at mData.
* the value does not include space for the null-terminator character.
*
* NOTE: this function returns 0 if mData is immutable (or the buffer
* is 0-sized).
*/
size_type NS_FASTCALL Capacity() const;
/**
* this helper function can be called prior to directly manipulating
* the contents of mData. see, for example, BeginWriting.
*/
NS_COM PRBool NS_FASTCALL EnsureMutable( size_type newLen = size_type(-1) );
/**
* returns true if this string overlaps with the given string fragment.
*/
PRBool IsDependentOn( const char_type *start, const char_type *end ) const
{
/**
* if it _isn't_ the case that one fragment starts after the other ends,
* or ends before the other starts, then, they conflict:
*
* !(f2.begin >= f1.end || f2.end <= f1.begin)
*
* Simplified, that gives us:
*/
return ( start < (mData + mLength) && end > mData );
}
/**
* this helper function stores the specified dataFlags in mFlags
*/
void SetDataFlags(PRUint32 dataFlags)
{
NS_ASSERTION((dataFlags & 0xFFFF0000) == 0, "bad flags");
mFlags = dataFlags | (mFlags & 0xFFFF0000);
}
public:
// mFlags is a bitwise combination of the following flags. the meaning
// and interpretation of these flags is an implementation detail.
//
// NOTE: these flags are declared public _only_ for convenience inside
// the string implementation.
enum
{
F_NONE = 0, // no flags
// data flags are in the lower 16-bits
F_TERMINATED = 1 << 0, // IsTerminated returns true
F_VOIDED = 1 << 1, // IsVoid returns true
F_SHARED = 1 << 2, // mData points to a heap-allocated, shared buffer
F_OWNED = 1 << 3, // mData points to a heap-allocated, raw buffer
F_FIXED = 1 << 4, // mData points to a fixed-size writable, dependent buffer
// class flags are in the upper 16-bits
F_CLASS_FIXED = 1 << 16 // indicates that |this| is of type nsTFixedString
};
//
// Some terminology:
//
// "dependent buffer" A dependent buffer is one that the string class
// does not own. The string class relies on some
// external code to ensure the lifetime of the
// dependent buffer.
//
// "shared buffer" A shared buffer is one that the string class
// allocates. When it allocates a shared string
// buffer, it allocates some additional space at
// the beginning of the buffer for additional
// fields, including a reference count and a
// buffer length. See nsStringHeader.
//
// "adopted buffer" An adopted buffer is a raw string buffer
// allocated on the heap (using nsMemory::Alloc)
// of which the string class subsumes ownership.
//
// Some comments about the string flags:
//
// F_SHARED, F_OWNED, and F_FIXED are all mutually exlusive. They
// indicate the allocation type of mData. If none of these flags
// are set, then the string buffer is dependent.
//
// F_SHARED, F_OWNED, or F_FIXED imply F_TERMINATED. This is because
// the string classes always allocate null-terminated buffers, and
// non-terminated substrings are always dependent.
//
// F_VOIDED implies F_TERMINATED, and moreover it implies that mData
// points to char_traits::sEmptyBuffer. Therefore, F_VOIDED is
// mutually exclusive with F_SHARED, F_OWNED, and F_FIXED.
//
};
NS_COM
int NS_FASTCALL Compare( const nsTSubstring_CharT::base_string_type& lhs, const nsTSubstring_CharT::base_string_type& rhs, const nsTStringComparator_CharT& = nsTDefaultStringComparator_CharT() );
inline
PRBool operator!=( const nsTSubstring_CharT::base_string_type& lhs, const nsTSubstring_CharT::base_string_type& rhs )
{
return !lhs.Equals(rhs);
}
inline
PRBool operator< ( const nsTSubstring_CharT::base_string_type& lhs, const nsTSubstring_CharT::base_string_type& rhs )
{
return Compare(lhs, rhs)< 0;
}
inline
PRBool operator<=( const nsTSubstring_CharT::base_string_type& lhs, const nsTSubstring_CharT::base_string_type& rhs )
{
return Compare(lhs, rhs)<=0;
}
inline
PRBool operator==( const nsTSubstring_CharT::base_string_type& lhs, const nsTSubstring_CharT::base_string_type& rhs )
{
return lhs.Equals(rhs);
}
inline
PRBool operator>=( const nsTSubstring_CharT::base_string_type& lhs, const nsTSubstring_CharT::base_string_type& rhs )
{
return Compare(lhs, rhs)>=0;
}
inline
PRBool operator> ( const nsTSubstring_CharT::base_string_type& lhs, const nsTSubstring_CharT::base_string_type& rhs )
{
return Compare(lhs, rhs)> 0;
}