tor-browser

uvectr32.h (8585B)

---

// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
**********************************************************************
*   Copyright (C) 1999-2011, International Business Machines
*   Corporation and others.  All Rights Reserved.
**********************************************************************
*/

//
//  UVector32 is a class implementing a vector of 32 bit integers.
//            It is similar to UVector, but holds int32_t values rather than pointers.
//            Most of the code is unchanged from UVector.
//

#ifndef UVECTOR32_H
#define UVECTOR32_H

#include "unicode/utypes.h"
#include "unicode/uobject.h"
#include "uhash.h"
#include "uassert.h"

U_NAMESPACE_BEGIN



/**
* <p>Ultralightweight C++ implementation of a <tt>void*</tt> vector
* that is (mostly) compatible with java.util.Vector.
*
* <p>This is a very simple implementation, written to satisfy an
* immediate porting need.  As such, it is not completely fleshed out,
* and it aims for simplicity and conformity.  Nonetheless, it serves
* its purpose (porting code from java that uses java.util.Vector)
* well, and it could be easily made into a more robust vector class.
*
* <p><b>Design notes</b>
*
* <p>There is index bounds checking, but little is done about it.  If
* indices are out of bounds, either nothing happens, or zero is
* returned.  We <em>do</em> avoid indexing off into the weeds.
*
* <p>There is detection of out of memory, but the handling is very
* coarse-grained -- similar to UnicodeString's protocol, but even
* coarser.  The class contains <em>one static flag</em> that is set
* when any call to <tt>new</tt> returns zero.  This allows the caller
* to use several vectors and make just one check at the end to see if
* a memory failure occurred.  This is more efficient than making a
* check after each call on each vector when doing many operations on
* multiple vectors.  The single static flag works best when memory
* failures are infrequent, and when recovery options are limited or
* nonexistent.
*
* <p><b>To do</b>
*
* <p>Improve the handling of index out of bounds errors.
*
* @author Alan Liu
*/
class U_COMMON_API UVector32 : public UObject {
private:
   int32_t   count;

   int32_t   capacity;
   
   int32_t   maxCapacity;   // Limit beyond which capacity is not permitted to grow.

   int32_t*  elements;

public:
   UVector32(UErrorCode &status);

   UVector32(int32_t initialCapacity, UErrorCode &status);

   virtual ~UVector32();

   /**
    * Assign this object to another (make this a copy of 'other').
    * Use the 'assign' function to assign each element.
    */
   void assign(const UVector32& other, UErrorCode &ec);

   /**
    * Compare this vector with another.  They will be considered
    * equal if they are of the same size and all elements are equal,
    * as compared using this object's comparer.
    */
   bool operator==(const UVector32& other) const;

   /**
    * Equivalent to !operator==()
    */
   inline bool operator!=(const UVector32& other) const;

   //------------------------------------------------------------
   // java.util.Vector API
   //------------------------------------------------------------

   inline void addElement(int32_t elem, UErrorCode &status);

   void setElementAt(int32_t elem, int32_t index);

   void insertElementAt(int32_t elem, int32_t index, UErrorCode &status);
   
   inline int32_t elementAti(int32_t index) const;

   UBool equals(const UVector32 &other) const;

   inline int32_t lastElementi() const;

   int32_t indexOf(int32_t elem, int32_t startIndex = 0) const;

   inline UBool contains(int32_t elem) const;

   UBool containsAll(const UVector32& other) const;

   UBool removeAll(const UVector32& other);

   UBool retainAll(const UVector32& other);

   void removeElementAt(int32_t index);

   void removeAllElements();

   inline int32_t size() const;

   inline UBool isEmpty() const;

   // Inline.  Use this one for speedy size check.
   inline UBool ensureCapacity(int32_t minimumCapacity, UErrorCode &status);

   // Out-of-line, handles actual growth.  Called by ensureCapacity() when necessary.
   UBool expandCapacity(int32_t minimumCapacity, UErrorCode &status);

   /**
    * Change the size of this vector as follows: If newSize is
    * smaller, then truncate the array, possibly deleting held
    * elements for i >= newSize.  If newSize is larger, grow the
    * array, filling in new slows with zero.
    */
   void setSize(int32_t newSize);

   //------------------------------------------------------------
   // New API
   //------------------------------------------------------------

   /**
    * Returns true if this vector contains none of the elements
    * of the given vector.
    * @param other vector to be checked for containment
    * @return true if the test condition is met
    */
   UBool containsNone(const UVector32& other) const;


   /**
    * Insert the given integer into this vector at its sorted position.
    * The current elements are assumed to be sorted already.
    */
   void sortedInsert(int32_t elem, UErrorCode& ec);

   /**
    * Returns a pointer to the internal array holding the vector.
    */
   inline int32_t *getBuffer() const;

   /**
    * Set the maximum allowed buffer capacity for this vector/stack.
    * Default with no limit set is unlimited, go until malloc() fails.
    * A Limit of zero means unlimited capacity.
    * Units are vector elements (32 bits each), not bytes.
    */
   void setMaxCapacity(int32_t limit);

   /**
    * ICU "poor man's RTTI", returns a UClassID for this class.
    */
   static UClassID U_EXPORT2 getStaticClassID();

   /**
    * ICU "poor man's RTTI", returns a UClassID for the actual class.
    */
   virtual UClassID getDynamicClassID() const override;

private:
   void _init(int32_t initialCapacity, UErrorCode &status);

   // Disallow
   UVector32(const UVector32&) = delete;

   // Disallow
   UVector32& operator=(const UVector32&) = delete;


   //  API Functions for Stack operations.
   //  In the original UVector, these were in a separate derived class, UStack.
   //  Here in UVector32, they are all together.
public:
   inline UBool empty() const;   // TODO:  redundant, same as empty().  Remove it?

   inline int32_t peeki() const;
   
   inline int32_t popi();
   
   inline int32_t push(int32_t i, UErrorCode &status);

   inline int32_t *reserveBlock(int32_t size, UErrorCode &status);
   inline int32_t *popFrame(int32_t size);
};


// UVector32 inlines

inline UBool UVector32::ensureCapacity(int32_t minimumCapacity, UErrorCode &status) {
   if ((minimumCapacity >= 0) && (capacity >= minimumCapacity)) {
       return true;
   } else {
       return expandCapacity(minimumCapacity, status);
   }
}

inline int32_t UVector32::elementAti(int32_t index) const {
   return (index >= 0 && count > 0 && count - index > 0) ? elements[index] : 0;
}


inline void UVector32::addElement(int32_t elem, UErrorCode &status) {
   if (ensureCapacity(count + 1, status)) {
       elements[count] = elem;
       count++;
   }
}

inline int32_t *UVector32::reserveBlock(int32_t size, UErrorCode &status) {
   if (ensureCapacity(count+size, status) == false) {
       return nullptr;
   }
   int32_t  *rp = elements+count;
   count += size;
   return rp;
}

inline int32_t *UVector32::popFrame(int32_t size) {
   U_ASSERT(count >= size);
   count -= size;
   if (count < 0) {
       count = 0;
   }
   return elements+count-size;
}



inline int32_t UVector32::size() const {
   return count;
}

inline UBool UVector32::isEmpty() const {
   return count == 0;
}

inline UBool UVector32::contains(int32_t obj) const {
   return indexOf(obj) >= 0;
}

inline int32_t UVector32::lastElementi() const {
   return elementAti(count-1);
}

inline bool UVector32::operator!=(const UVector32& other) const {
   return !operator==(other);
}

inline int32_t *UVector32::getBuffer() const {
   return elements;
}


// UStack inlines

inline UBool UVector32::empty() const {
   return isEmpty();
}

inline int32_t UVector32::peeki() const {
   return lastElementi();
}

inline int32_t UVector32::push(int32_t i, UErrorCode &status) {
   addElement(i, status);
   return i;
}

inline int32_t UVector32::popi() {
   int32_t result = 0;
   if (count > 0) {
       count--;
       result = elements[count];
   }
   return result;
}

U_NAMESPACE_END

#endif