mirror of https://github.com/encounter/SDL.git
Replaced SDL_qsort with public domain code from PDCLib: http://pdclib.e43.eu/
This commit is contained in:
Ryan C. Gordon
parent
33af421d7b
commit
014956ac1d
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@ -31,10 +31,6 @@ Copyright: 1995 Erik Corry
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1995 Brown University
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1995 Brown University
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License: BrownUn_UnCalifornia_ErikCorry
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License: BrownUn_UnCalifornia_ErikCorry
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Files: src/stdlib/SDL_qsort.c
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Copyright: 1998 Gareth McCaughan
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License: Gareth_McCaughan
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Files: src/test/SDL_test_md5.c
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Files: src/test/SDL_test_md5.c
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Copyright: 1997-2016 Sam Lantinga <slouken@libsdl.org>
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Copyright: 1997-2016 Sam Lantinga <slouken@libsdl.org>
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1990 RSA Data Security, Inc.
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1990 RSA Data Security, Inc.
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@ -270,13 +266,6 @@ License: BrownUn_UnCalifornia_ErikCorry
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* SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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* SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
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*/
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*/
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License: Gareth_McCaughan
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You may use it in anything you like; you may make money
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out of it; you may distribute it in object form or as
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part of an executable without including source code;
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you don't have to credit me. (But it would be nice if
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you did.)
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License: Johnson_M._Hart
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License: Johnson_M._Hart
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Permission is granted for any and all use providing that this
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Permission is granted for any and all use providing that this
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copyright is properly acknowledged.
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copyright is properly acknowledged.
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@ -1,58 +1,5 @@
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/* qsort.c
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* (c) 1998 Gareth McCaughan
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*
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* This is a drop-in replacement for the C library's |qsort()| routine.
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*
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* Features:
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* - Median-of-three pivoting (and more)
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* - Truncation and final polishing by a single insertion sort
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* - Early truncation when no swaps needed in pivoting step
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* - Explicit recursion, guaranteed not to overflow
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* - A few little wrinkles stolen from the GNU |qsort()|.
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* - separate code for non-aligned / aligned / word-size objects
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*
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* This code may be reproduced freely provided
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* - this file is retained unaltered apart from minor
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* changes for portability and efficiency
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* - no changes are made to this comment
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* - any changes that *are* made are clearly flagged
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* - the _ID string below is altered by inserting, after
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* the date, the string " altered" followed at your option
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* by other material. (Exceptions: you may change the name
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* of the exported routine without changing the ID string.
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* You may change the values of the macros TRUNC_* and
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* PIVOT_THRESHOLD without changing the ID string, provided
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* they remain constants with TRUNC_nonaligned, TRUNC_aligned
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* and TRUNC_words/WORD_BYTES between 8 and 24, and
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* PIVOT_THRESHOLD between 32 and 200.)
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*
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* You may use it in anything you like; you may make money
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* out of it; you may distribute it in object form or as
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* part of an executable without including source code;
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* you don't have to credit me. (But it would be nice if
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* you did.)
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*
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* If you find problems with this code, or find ways of
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* making it significantly faster, please let me know!
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* My e-mail address, valid as of early 1998 and certainly
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* OK for at least the next 18 months, is
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* gjm11@dpmms.cam.ac.uk
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* Thanks!
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*
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* Gareth McCaughan Peterhouse Cambridge 1998
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*/
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#if defined(__clang_analyzer__) && !defined(SDL_DISABLE_ANALYZE_MACROS)
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#define SDL_DISABLE_ANALYZE_MACROS 1
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#endif
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#include "../SDL_internal.h"
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#include "../SDL_internal.h"
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/*
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#include <assert.h>
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#include <stdlib.h>
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#include <string.h>
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*/
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#include "SDL_stdinc.h"
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#include "SDL_stdinc.h"
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#include "SDL_assert.h"
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#include "SDL_assert.h"
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@ -64,418 +11,203 @@ SDL_qsort(void *base, size_t nmemb, size_t size, int (*compare) (const void *, c
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}
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}
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#else
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#else
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#ifdef assert
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#ifdef REGTEST
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#undef assert
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#undef REGTEST
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#endif
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#endif
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#define assert(X) SDL_assert(X)
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#ifdef malloc
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#ifdef TEST
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#undef malloc
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#undef TEST
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#endif
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#endif
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#define malloc SDL_malloc
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#ifdef free
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#ifndef _PDCLIB_memswp
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#undef free
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#define _PDCLIB_memswp( i, j, size ) char tmp; do { tmp = *i; *i++ = *j; *j++ = tmp; } while ( --size );
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#endif
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#endif
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#define free SDL_free
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#ifdef memcpy
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#ifndef _PDCLIB_size_t
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#undef memcpy
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#define _PDCLIB_size_t size_t
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#endif
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#endif
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#define memcpy SDL_memcpy
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#ifdef memmove
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#undef memmove
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#endif
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#define memmove SDL_memmove
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#ifdef qsort
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#undef qsort
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#endif
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#define qsort SDL_qsort
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static const char _ID[] = "<qsort.c gjm 1.12 1998-03-19>";
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#define qsort SDL_qsort
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/* How many bytes are there per word? (Must be a power of 2,
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#define inline SDL_INLINE
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* and must in fact equal sizeof(int).)
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*/
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#define WORD_BYTES sizeof(int)
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/* How big does our stack need to be? Answer: one entry per
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/*
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* bit in a |size_t|.
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This code came from PDCLib, under the public domain. Specifically this:
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*/
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https://bitbucket.org/pdclib/pdclib/raw/a82b02d0c7d4ed633b97f2a7639d9a10b1c92ec8/functions/stdlib/qsort.c
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#define STACK_SIZE (8*sizeof(size_t))
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The _PDCLIB_memswp macro was from
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https://bitbucket.org/pdclib/pdclib/src/a82b02d0c7d4ed633b97f2a7639d9a10b1c92ec8/platform/posix/internals/_PDCLIB_config.h?at=default&fileviewer=file-view-default#_PDCLIB_config.h-28
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/* Different situations have slightly different requirements,
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Everything below this comment until the HAVE_QSORT #endif was from PDCLib.
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* and we make life epsilon easier by using different truncation
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--ryan.
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* points for the three different cases.
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*/
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* So far, I have tuned TRUNC_words and guessed that the same
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* value might work well for the other two cases. Of course
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* what works well on my machine might work badly on yours.
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*/
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#define TRUNC_nonaligned 12
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#define TRUNC_aligned 12
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#define TRUNC_words 12*WORD_BYTES /* nb different meaning */
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/* We use a simple pivoting algorithm for shortish sub-arrays
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/* $Id$ */
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* and a more complicated one for larger ones. The threshold
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* is PIVOT_THRESHOLD.
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*/
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#define PIVOT_THRESHOLD 40
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typedef struct
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/* qsort( void *, size_t, size_t, int(*)( const void *, const void * ) )
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This file is part of the Public Domain C Library (PDCLib).
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Permission is granted to use, modify, and / or redistribute at will.
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*/
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#include <stdlib.h>
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#ifndef REGTEST
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/* This implementation is taken from Paul Edward's PDPCLIB.
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Original code is credited to Raymond Gardner, Englewood CO.
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Minor mods are credited to Paul Edwards.
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Some reformatting and simplification done by Martin Baute.
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All code is still Public Domain.
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*/
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/* Wrapper for _PDCLIB_memswp protects against multiple argument evaluation. */
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static inline void memswp( char * i, char * j, size_t size )
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{
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{
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char *first;
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_PDCLIB_memswp( i, j, size );
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char *last;
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} stack_entry;
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#define pushLeft {stack[stacktop].first=ffirst;stack[stacktop++].last=last;}
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#define pushRight {stack[stacktop].first=first;stack[stacktop++].last=llast;}
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#define doLeft {first=ffirst;llast=last;continue;}
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#define doRight {ffirst=first;last=llast;continue;}
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#define pop {if (--stacktop<0) break;\
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first=ffirst=stack[stacktop].first;\
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last=llast=stack[stacktop].last;\
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continue;}
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/* Some comments on the implementation.
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* 1. When we finish partitioning the array into "low"
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* and "high", we forget entirely about short subarrays,
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* because they'll be done later by insertion sort.
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* Doing lots of little insertion sorts might be a win
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* on large datasets for locality-of-reference reasons,
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* but it makes the code much nastier and increases
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* bookkeeping overhead.
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* 2. We always save the shorter and get to work on the
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* longer. This guarantees that every time we push
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* an item onto the stack its size is <= 1/2 of that
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* of its parent; so the stack can't need more than
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* log_2(max-array-size) entries.
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* 3. We choose a pivot by looking at the first, last
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* and middle elements. We arrange them into order
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* because it's easy to do that in conjunction with
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* choosing the pivot, and it makes things a little
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* easier in the partitioning step. Anyway, the pivot
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* is the middle of these three. It's still possible
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* to construct datasets where the algorithm takes
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* time of order n^2, but it simply never happens in
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* practice.
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* 3' Newsflash: On further investigation I find that
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* it's easy to construct datasets where median-of-3
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* simply isn't good enough. So on large-ish subarrays
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* we do a more sophisticated pivoting: we take three
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* sets of 3 elements, find their medians, and then
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* take the median of those.
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* 4. We copy the pivot element to a separate place
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* because that way we can always do our comparisons
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* directly against a pointer to that separate place,
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* and don't have to wonder "did we move the pivot
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* element?". This makes the inner loop better.
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* 5. It's possible to make the pivoting even more
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* reliable by looking at more candidates when n
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* is larger. (Taking this to its logical conclusion
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* results in a variant of quicksort that doesn't
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* have that n^2 worst case.) However, the overhead
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* from the extra bookkeeping means that it's just
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* not worth while.
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* 6. This is pretty clean and portable code. Here are
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* all the potential portability pitfalls and problems
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* I know of:
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* - In one place (the insertion sort) I construct
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* a pointer that points just past the end of the
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* supplied array, and assume that (a) it won't
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* compare equal to any pointer within the array,
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* and (b) it will compare equal to a pointer
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* obtained by stepping off the end of the array.
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* These might fail on some segmented architectures.
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* - I assume that there are 8 bits in a |char| when
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* computing the size of stack needed. This would
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* fail on machines with 9-bit or 16-bit bytes.
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* - I assume that if |((int)base&(sizeof(int)-1))==0|
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* and |(size&(sizeof(int)-1))==0| then it's safe to
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* get at array elements via |int*|s, and that if
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* actually |size==sizeof(int)| as well then it's
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* safe to treat the elements as |int|s. This might
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* fail on systems that convert pointers to integers
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* in non-standard ways.
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* - I assume that |8*sizeof(size_t)<=INT_MAX|. This
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* would be false on a machine with 8-bit |char|s,
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* 16-bit |int|s and 4096-bit |size_t|s. :-)
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*/
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/* The recursion logic is the same in each case: */
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#define Recurse(Trunc) \
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{ size_t l=last-ffirst,r=llast-first; \
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if (l<Trunc) { \
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if (r>=Trunc) doRight \
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else pop \
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} \
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else if (l<=r) { pushLeft; doRight } \
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else if (r>=Trunc) { pushRight; doLeft }\
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else doLeft \
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}
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/* and so is the pivoting logic: */
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#define Pivot(swapper,sz) \
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if ((size_t)(last-first)>PIVOT_THRESHOLD*sz) mid=pivot_big(first,mid,last,sz,compare);\
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else { \
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if (compare(first,mid)<0) { \
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if (compare(mid,last)>0) { \
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swapper(mid,last); \
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if (compare(first,mid)>0) swapper(first,mid);\
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} \
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} \
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else { \
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if (compare(mid,last)>0) swapper(first,last)\
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else { \
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swapper(first,mid); \
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if (compare(mid,last)>0) swapper(mid,last);\
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} \
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} \
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first+=sz; last-=sz; \
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}
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#ifdef DEBUG_QSORT
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#include <stdio.h>
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#endif
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/* and so is the partitioning logic: */
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#define Partition(swapper,sz) { \
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int swapped=0; \
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do { \
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while (compare(first,pivot)<0) first+=sz; \
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while (compare(pivot,last)<0) last-=sz; \
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if (first<last) { \
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swapper(first,last); swapped=1; \
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first+=sz; last-=sz; } \
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else if (first==last) { first+=sz; last-=sz; break; }\
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} while (first<=last); \
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if (!swapped) pop \
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}
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}
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/* and so is the pre-insertion-sort operation of putting
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/* For small sets, insertion sort is faster than quicksort.
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* the smallest element into place as a sentinel.
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T is the threshold below which insertion sort will be used.
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* Doing this makes the inner loop nicer. I got this
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Must be 3 or larger.
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* idea from the GNU implementation of qsort().
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*/
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*/
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#define T 7
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#define PreInsertion(swapper,limit,sz) \
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first=base; \
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last=first + (nmemb>limit ? limit : nmemb-1)*sz;\
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while (last!=base) { \
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if (compare(first,last)>0) first=last; \
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last-=sz; } \
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if (first!=base) swapper(first,(char*)base);
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/* and so is the insertion sort, in the first two cases: */
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/* Macros for handling the QSort stack */
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#define Insertion(swapper) \
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#define PREPARE_STACK char * stack[STACKSIZE]; char * * stackptr = stack
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last=((char*)base)+nmemb*size; \
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#define PUSH( base, limit ) stackptr[0] = base; stackptr[1] = limit; stackptr += 2
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for (first=((char*)base)+size;first!=last;first+=size) { \
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#define POP( base, limit ) stackptr -= 2; base = stackptr[0]; limit = stackptr[1]
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char *test; \
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/* TODO: Stack usage is log2( nmemb ) (minus what T shaves off the worst case).
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/* Find the right place for |first|. \
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Worst-case nmemb is platform dependent and should probably be
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* My apologies for var reuse. */ \
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configured through _PDCLIB_config.h.
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for (test=first-size;compare(test,first)>0;test-=size) ; \
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*/
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test+=size; \
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#define STACKSIZE 64
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if (test!=first) { \
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/* Shift everything in [test,first) \
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* up by one, and place |first| \
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* where |test| is. */ \
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memcpy(pivot,first,size); \
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memmove(test+size,test,first-test); \
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memcpy(test,pivot,size); \
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} \
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}
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#define SWAP_nonaligned(a,b) { \
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void qsort( void * base, size_t nmemb, size_t size, int (*compar)( const void *, const void * ) )
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register char *aa=(a),*bb=(b); \
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register size_t sz=size; \
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do { register char t=*aa; *aa++=*bb; *bb++=t; } while (--sz); }
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#define SWAP_aligned(a,b) { \
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register int *aa=(int*)(a),*bb=(int*)(b); \
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|
||||||
register size_t sz=size; \
|
|
||||||
do { register int t=*aa;*aa++=*bb; *bb++=t; } while (sz-=WORD_BYTES); }
|
|
||||||
|
|
||||||
#define SWAP_words(a,b) { \
|
|
||||||
register int t=*((int*)a); *((int*)a)=*((int*)b); *((int*)b)=t; }
|
|
||||||
|
|
||||||
/* ---------------------------------------------------------------------- */
|
|
||||||
|
|
||||||
static char *
|
|
||||||
pivot_big(char *first, char *mid, char *last, size_t size,
|
|
||||||
int compare(const void *, const void *))
|
|
||||||
{
|
{
|
||||||
size_t d = (((last - first) / size) >> 3) * size;
|
char * i;
|
||||||
char *m1, *m2, *m3;
|
char * j;
|
||||||
|
_PDCLIB_size_t thresh = T * size;
|
||||||
|
char * base_ = (char *)base;
|
||||||
|
char * limit = base_ + nmemb * size;
|
||||||
|
PREPARE_STACK;
|
||||||
|
|
||||||
|
for ( ;; )
|
||||||
{
|
{
|
||||||
char *a = first, *b = first + d, *c = first + 2 * d;
|
if ( (size_t)( limit - base_ ) > thresh ) /* QSort for more than T elements. */
|
||||||
#ifdef DEBUG_QSORT
|
{
|
||||||
fprintf(stderr, "< %d %d %d\n", *(int *) a, *(int *) b, *(int *) c);
|
/* We work from second to last - first will be pivot element. */
|
||||||
#endif
|
i = base_ + size;
|
||||||
m1 = compare(a, b) < 0 ?
|
j = limit - size;
|
||||||
(compare(b, c) < 0 ? b : (compare(a, c) < 0 ? c : a))
|
/* We swap first with middle element, then sort that with second
|
||||||
: (compare(a, c) < 0 ? a : (compare(b, c) < 0 ? c : b));
|
and last element so that eventually first element is the median
|
||||||
}
|
of the three - avoiding pathological pivots.
|
||||||
{
|
TODO: Instead of middle element, chose one randomly.
|
||||||
char *a = mid - d, *b = mid, *c = mid + d;
|
*/
|
||||||
#ifdef DEBUG_QSORT
|
memswp( ( ( ( (size_t)( limit - base_ ) ) / size ) / 2 ) * size + base_, base_, size );
|
||||||
fprintf(stderr, ". %d %d %d\n", *(int *) a, *(int *) b, *(int *) c);
|
if ( compar( i, j ) > 0 ) memswp( i, j, size );
|
||||||
#endif
|
if ( compar( base_, j ) > 0 ) memswp( base_, j, size );
|
||||||
m2 = compare(a, b) < 0 ?
|
if ( compar( i, base_ ) > 0 ) memswp( i, base_, size );
|
||||||
(compare(b, c) < 0 ? b : (compare(a, c) < 0 ? c : a))
|
/* Now we have the median for pivot element, entering main Quicksort. */
|
||||||
: (compare(a, c) < 0 ? a : (compare(b, c) < 0 ? c : b));
|
for ( ;; )
|
||||||
}
|
|
||||||
{
|
|
||||||
char *a = last - 2 * d, *b = last - d, *c = last;
|
|
||||||
#ifdef DEBUG_QSORT
|
|
||||||
fprintf(stderr, "> %d %d %d\n", *(int *) a, *(int *) b, *(int *) c);
|
|
||||||
#endif
|
|
||||||
m3 = compare(a, b) < 0 ?
|
|
||||||
(compare(b, c) < 0 ? b : (compare(a, c) < 0 ? c : a))
|
|
||||||
: (compare(a, c) < 0 ? a : (compare(b, c) < 0 ? c : b));
|
|
||||||
}
|
|
||||||
#ifdef DEBUG_QSORT
|
|
||||||
fprintf(stderr, "-> %d %d %d\n", *(int *) m1, *(int *) m2, *(int *) m3);
|
|
||||||
#endif
|
|
||||||
return compare(m1, m2) < 0 ?
|
|
||||||
(compare(m2, m3) < 0 ? m2 : (compare(m1, m3) < 0 ? m3 : m1))
|
|
||||||
: (compare(m1, m3) < 0 ? m1 : (compare(m2, m3) < 0 ? m3 : m2));
|
|
||||||
}
|
|
||||||
|
|
||||||
/* ---------------------------------------------------------------------- */
|
|
||||||
|
|
||||||
static void
|
|
||||||
qsort_nonaligned(void *base, size_t nmemb, size_t size,
|
|
||||||
int (*compare) (const void *, const void *))
|
|
||||||
{
|
|
||||||
|
|
||||||
stack_entry stack[STACK_SIZE];
|
|
||||||
int stacktop = 0;
|
|
||||||
char *first, *last;
|
|
||||||
char *pivot = malloc(size);
|
|
||||||
size_t trunc = TRUNC_nonaligned * size;
|
|
||||||
assert(pivot != 0);
|
|
||||||
|
|
||||||
first = (char *) base;
|
|
||||||
last = first + (nmemb - 1) * size;
|
|
||||||
|
|
||||||
if ((size_t) (last - first) > trunc) {
|
|
||||||
char *ffirst = first, *llast = last;
|
|
||||||
while (1) {
|
|
||||||
/* Select pivot */
|
|
||||||
{
|
{
|
||||||
char *mid = first + size * ((last - first) / size >> 1);
|
do
|
||||||
Pivot(SWAP_nonaligned, size);
|
{
|
||||||
memcpy(pivot, mid, size);
|
/* move i right until *i >= pivot */
|
||||||
|
i += size;
|
||||||
|
} while ( compar( i, base_ ) < 0 );
|
||||||
|
do
|
||||||
|
{
|
||||||
|
/* move j left until *j <= pivot */
|
||||||
|
j -= size;
|
||||||
|
} while ( compar( j, base_ ) > 0 );
|
||||||
|
if ( i > j )
|
||||||
|
{
|
||||||
|
/* break loop if pointers crossed */
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
/* else swap elements, keep scanning */
|
||||||
|
memswp( i, j, size );
|
||||||
}
|
}
|
||||||
/* Partition. */
|
/* move pivot into correct place */
|
||||||
Partition(SWAP_nonaligned, size);
|
memswp( base_, j, size );
|
||||||
/* Prepare to recurse/iterate. */
|
/* larger subfile base / limit to stack, sort smaller */
|
||||||
Recurse(trunc)}
|
if ( j - base_ > limit - i )
|
||||||
}
|
|
||||||
PreInsertion(SWAP_nonaligned, TRUNC_nonaligned, size);
|
|
||||||
Insertion(SWAP_nonaligned);
|
|
||||||
free(pivot);
|
|
||||||
}
|
|
||||||
|
|
||||||
static void
|
|
||||||
qsort_aligned(void *base, size_t nmemb, size_t size,
|
|
||||||
int (*compare) (const void *, const void *))
|
|
||||||
{
|
|
||||||
|
|
||||||
stack_entry stack[STACK_SIZE];
|
|
||||||
int stacktop = 0;
|
|
||||||
char *first, *last;
|
|
||||||
char *pivot = malloc(size);
|
|
||||||
size_t trunc = TRUNC_aligned * size;
|
|
||||||
assert(pivot != 0);
|
|
||||||
|
|
||||||
first = (char *) base;
|
|
||||||
last = first + (nmemb - 1) * size;
|
|
||||||
|
|
||||||
if ((size_t) (last - first) > trunc) {
|
|
||||||
char *ffirst = first, *llast = last;
|
|
||||||
while (1) {
|
|
||||||
/* Select pivot */
|
|
||||||
{
|
{
|
||||||
char *mid = first + size * ((last - first) / size >> 1);
|
/* left is larger */
|
||||||
Pivot(SWAP_aligned, size);
|
PUSH( base_, j );
|
||||||
memcpy(pivot, mid, size);
|
base_ = i;
|
||||||
}
|
}
|
||||||
/* Partition. */
|
else
|
||||||
Partition(SWAP_aligned, size);
|
|
||||||
/* Prepare to recurse/iterate. */
|
|
||||||
Recurse(trunc)}
|
|
||||||
}
|
|
||||||
PreInsertion(SWAP_aligned, TRUNC_aligned, size);
|
|
||||||
Insertion(SWAP_aligned);
|
|
||||||
free(pivot);
|
|
||||||
}
|
|
||||||
|
|
||||||
static void
|
|
||||||
qsort_words(void *base, size_t nmemb,
|
|
||||||
int (*compare) (const void *, const void *))
|
|
||||||
{
|
|
||||||
|
|
||||||
stack_entry stack[STACK_SIZE];
|
|
||||||
int stacktop = 0;
|
|
||||||
char *first, *last;
|
|
||||||
char *pivot = malloc(WORD_BYTES);
|
|
||||||
assert(pivot != 0);
|
|
||||||
|
|
||||||
first = (char *) base;
|
|
||||||
last = first + (nmemb - 1) * WORD_BYTES;
|
|
||||||
|
|
||||||
if (last - first > TRUNC_words) {
|
|
||||||
char *ffirst = first, *llast = last;
|
|
||||||
while (1) {
|
|
||||||
#ifdef DEBUG_QSORT
|
|
||||||
fprintf(stderr, "Doing %d:%d: ",
|
|
||||||
(first - (char *) base) / WORD_BYTES,
|
|
||||||
(last - (char *) base) / WORD_BYTES);
|
|
||||||
#endif
|
|
||||||
/* Select pivot */
|
|
||||||
{
|
{
|
||||||
char *mid =
|
/* right is larger */
|
||||||
first + WORD_BYTES * ((last - first) / (2 * WORD_BYTES));
|
PUSH( i, limit );
|
||||||
Pivot(SWAP_words, WORD_BYTES);
|
limit = j;
|
||||||
*(int *) pivot = *(int *) mid;
|
}
|
||||||
|
}
|
||||||
|
else /* insertion sort for less than T elements */
|
||||||
|
{
|
||||||
|
for ( j = base_, i = j + size; i < limit; j = i, i += size )
|
||||||
|
{
|
||||||
|
for ( ; compar( j, j + size ) > 0; j -= size )
|
||||||
|
{
|
||||||
|
memswp( j, j + size, size );
|
||||||
|
if ( j == base_ )
|
||||||
|
{
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
}
|
||||||
|
if ( stackptr != stack ) /* if any entries on stack */
|
||||||
|
{
|
||||||
|
POP( base_, limit );
|
||||||
|
}
|
||||||
|
else /* else stack empty, done */
|
||||||
|
{
|
||||||
|
break;
|
||||||
}
|
}
|
||||||
#ifdef DEBUG_QSORT
|
|
||||||
fprintf(stderr, "pivot=%d\n", *(int *) pivot);
|
|
||||||
#endif
|
|
||||||
/* Partition. */
|
|
||||||
Partition(SWAP_words, WORD_BYTES);
|
|
||||||
/* Prepare to recurse/iterate. */
|
|
||||||
Recurse(TRUNC_words)}
|
|
||||||
}
|
|
||||||
PreInsertion(SWAP_words, (TRUNC_words / WORD_BYTES), WORD_BYTES);
|
|
||||||
/* Now do insertion sort. */
|
|
||||||
last = ((char *) base) + nmemb * WORD_BYTES;
|
|
||||||
for (first = ((char *) base) + WORD_BYTES; first != last;
|
|
||||||
first += WORD_BYTES) {
|
|
||||||
/* Find the right place for |first|. My apologies for var reuse */
|
|
||||||
int *pl = (int *) (first - WORD_BYTES), *pr = (int *) first;
|
|
||||||
*(int *) pivot = *(int *) first;
|
|
||||||
for (; compare(pl, pivot) > 0; pr = pl, --pl) {
|
|
||||||
*pr = *pl;
|
|
||||||
}
|
}
|
||||||
if (pr != (int *) first)
|
|
||||||
*pr = *(int *) pivot;
|
|
||||||
}
|
}
|
||||||
free(pivot);
|
|
||||||
}
|
}
|
||||||
|
|
||||||
/* ---------------------------------------------------------------------- */
|
#endif
|
||||||
|
|
||||||
void
|
#ifdef TEST
|
||||||
qsort(void *base, size_t nmemb, size_t size,
|
#include <_PDCLIB_test.h>
|
||||||
int (*compare) (const void *, const void *))
|
#include <string.h>
|
||||||
|
#include <limits.h>
|
||||||
|
|
||||||
|
static int compare( const void * left, const void * right )
|
||||||
{
|
{
|
||||||
|
return *( (unsigned char *)left ) - *( (unsigned char *)right );
|
||||||
if (nmemb <= 1)
|
|
||||||
return;
|
|
||||||
if (((uintptr_t) base | size) & (WORD_BYTES - 1))
|
|
||||||
qsort_nonaligned(base, nmemb, size, compare);
|
|
||||||
else if (size != WORD_BYTES)
|
|
||||||
qsort_aligned(base, nmemb, size, compare);
|
|
||||||
else
|
|
||||||
qsort_words(base, nmemb, compare);
|
|
||||||
}
|
}
|
||||||
|
|
||||||
#endif /* !SDL_qsort */
|
int main( void )
|
||||||
|
{
|
||||||
|
char presort[] = { "shreicnyjqpvozxmbt" };
|
||||||
|
char sorted1[] = { "bcehijmnopqrstvxyz" };
|
||||||
|
char sorted2[] = { "bticjqnyozpvreshxm" };
|
||||||
|
char s[19];
|
||||||
|
strcpy( s, presort );
|
||||||
|
qsort( s, 18, 1, compare );
|
||||||
|
TESTCASE( strcmp( s, sorted1 ) == 0 );
|
||||||
|
strcpy( s, presort );
|
||||||
|
qsort( s, 9, 2, compare );
|
||||||
|
TESTCASE( strcmp( s, sorted2 ) == 0 );
|
||||||
|
strcpy( s, presort );
|
||||||
|
qsort( s, 1, 1, compare );
|
||||||
|
TESTCASE( strcmp( s, presort ) == 0 );
|
||||||
|
#if defined(REGTEST) && (__BSD_VISIBLE || __APPLE__)
|
||||||
|
puts( "qsort.c: Skipping test #4 for BSD as it goes into endless loop here." );
|
||||||
|
#else
|
||||||
|
qsort( s, 100, 0, compare );
|
||||||
|
TESTCASE( strcmp( s, presort ) == 0 );
|
||||||
|
#endif
|
||||||
|
return TEST_RESULTS;
|
||||||
|
}
|
||||||
|
|
||||||
|
#endif
|
||||||
|
|
||||||
|
#endif /* HAVE_QSORT */
|
||||||
|
|
||||||
/* vi: set ts=4 sw=4 expandtab: */
|
/* vi: set ts=4 sw=4 expandtab: */
|
||||||
|
|
|
||||||
Loading…
Reference in New Issue