src/gromacs/utility/qsort_threadsafe.h

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  35 /*! \libinternal \file
  36  * \brief
  37  * Portable implementation of threadsafe quicksort.
  38  *
  39  * This module provides a \Gromacs version of the qsort() routine defined.
  40  * It is not highly optimized, but it is threadsafe, i.e. multiple threads
  41  * can simultaneously call gmx_qsort() with different data.
  42  *
  43  * The rational is that some implementations of qsort() are not threadsafe.
  44  * For instance qsort() in glibc contains a bug which makes it not threadsafe:
  45  * http://sources.redhat.com/bugzilla/show_bug.cgi?id=11655
  46  * On the other hand, system qsort() might be faster than our own.
  47  *
  48  * \inlibraryapi
  49  * \ingroup module_utility
  50  */
  51 #ifndef GMX_UTILITY_QSORT_THREADSAFE_H
  52 #define GMX_UTILITY_QSORT_THREADSAFE_H
  53
  54 #include <stdlib.h>
  55
  56 /* For GMX_THREAD_MPI */
  57 #include "config.h"
  58
  59 #ifdef __cplusplus
  60 extern "C"
  61 {
  62 #endif
  63 #if 0
  64 } /* fixes auto-indentation problems */
  65 #endif
  66
  67 /*! \addtogroup module_utility
  68  * \{
  69  */
  70
  71 /*! \brief
  72  * Portable threadsafe sort routine.
  73  *
  74  * \param base    Pointer to first element in list to sort
  75  * \param nmemb   Number of elements in list
  76  * \param size    Size in bytes of each element
  77  * \param compar  Comparison function that takes two pointers to elements
  78  *                being compared as arguments.  The function should return an
  79  *                integer less than, equal to, or greater than zero if the
  80  *                first argument is considered to be respectively less than,
  81  *                equal to, or greater than the second.
  82  */
  83 void
  84 gmx_qsort(void            *base,
  85           size_t           nmemb,
  86           size_t           size,
  87           int            (*compar)(const void *, const void *));
  88
  89
  90 /*! \def gmx_qsort_threadsafe
  91  * \brief
  92  * Threadsafe qsort().
  93  *
  94  * Expands to gmx_qsort() if Gromacs is built with threading, or system qsort()
  95  * otherwise.
  96  */
  97 #ifdef GMX_THREAD_MPI
  98 #define gmx_qsort_threadsafe gmx_qsort
  99 #else
 100 #define gmx_qsort_threadsafe qsort
 101 #endif
 102
 103 /*! \} */
 104
 105 #ifdef __cplusplus
 106 }
 107 #endif
 108
 109 #endif