7zip/UI/Common/SortUtils.cpp


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// SortUtils.cpp

#include "StdAfx.h"

#include "SortUtils.h"

static int __cdecl CompareStrings(const void *a1, const void *a2)
{
  const UString &s1 = *(*(*((const UString ***)a1)));
  const UString &s2 = *(*(*((const UString ***)a2)));
  return s1.CompareNoCase(s2);
}

void SortStringsToIndices(const UStringVector &strings, CIntVector &indices)
{
  indices.Clear();
  if (strings.IsEmpty())
    return;
  int numItems = strings.Size();
  CPointerVector pointers;
  pointers.Reserve(numItems);
  indices.Reserve(numItems);
  int i;
  for(i = 0; i < numItems; i++)
    pointers.Add((void *)&strings.CPointerVector::operator[](i));
  void **stringsBase  = (void **)pointers[0];
  qsort(&pointers[0], numItems, sizeof(void *), CompareStrings);
  for(i = 0; i < numItems; i++)
    indices.Add((void **)pointers[i] - stringsBase);
}

void SortStrings(const UStringVector &src, UStringVector &dest)
{
  CIntVector indices;
  SortStringsToIndices(src, indices);
  dest.Clear();
  dest.Reserve(indices.Size());
  for (int i = 0; i < indices.Size(); i++)
    dest.Add(src[indices[i]]);
}