sdl-ios-xcode: src/stdlib/SDL

annotate src/stdlib/SDL_qsort.c @ 3476:ab99313951cd

Increased tolerance a little bit more for multiple blending passes accumulating error.

author	Sam Lantinga <slouken@libsdl.org>
date	Sat, 21 Nov 2009 07:46:12 +0000
parents	dc1eb82ffdaa
children	0aaa7f52d1c6

rev	line source
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	1 /* qsort.c
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	2 * (c) 1998 Gareth McCaughan
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	3 *
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	4 * This is a drop-in replacement for the C library's \|qsort()\| routine.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	5 *
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	6 * Features:
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	7 * - Median-of-three pivoting (and more)
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	8 * - Truncation and final polishing by a single insertion sort
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	9 * - Early truncation when no swaps needed in pivoting step
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	10 * - Explicit recursion, guaranteed not to overflow
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	11 * - A few little wrinkles stolen from the GNU \|qsort()\|.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	12 * - separate code for non-aligned / aligned / word-size objects
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	13 *
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	14 * This code may be reproduced freely provided
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	15 * - this file is retained unaltered apart from minor
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	16 * changes for portability and efficiency
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	17 * - no changes are made to this comment
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	18 * - any changes that are made are clearly flagged
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	19 * - the _ID string below is altered by inserting, after
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	20 * the date, the string " altered" followed at your option
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	21 * by other material. (Exceptions: you may change the name
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	22 * of the exported routine without changing the ID string.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	23 * You may change the values of the macros TRUNC_* and
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	24 * PIVOT_THRESHOLD without changing the ID string, provided
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	25 * they remain constants with TRUNC_nonaligned, TRUNC_aligned
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	26 * and TRUNC_words/WORD_BYTES between 8 and 24, and
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	27 * PIVOT_THRESHOLD between 32 and 200.)
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	28 *
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	29 * You may use it in anything you like; you may make money
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	30 * out of it; you may distribute it in object form or as
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	31 * part of an executable without including source code;
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	32 * you don't have to credit me. (But it would be nice if
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	33 * you did.)
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	34 *
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	35 * If you find problems with this code, or find ways of
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	36 * making it significantly faster, please let me know!
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	37 * My e-mail address, valid as of early 1998 and certainly
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	38 * OK for at least the next 18 months, is
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	39 * gjm11@dpmms.cam.ac.uk
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	40 * Thanks!
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	41 *
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	42 * Gareth McCaughan Peterhouse Cambridge 1998
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	43 */
1402 d910939febfa Use consistent identifiers for the various platforms we support. Sam Lantinga <slouken@libsdl.org> parents: 1354 diff changeset	44 #include "SDL_config.h"
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	45
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	46 /*
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	47 #include <assert.h>
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	48 #include <stdlib.h>
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	49 #include <string.h>
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	50 */
1354 22f39393668a Fixed build problem with SDL_string.c Sam Lantinga <slouken@libsdl.org> parents: 1337 diff changeset	51 #include "SDL_stdinc.h"
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	52
1337 c687f06c7473 Don't touch code that we brought in from other sources Sam Lantinga <slouken@libsdl.org> parents: 1336 diff changeset	53 #define assert(X)
c687f06c7473 Don't touch code that we brought in from other sources Sam Lantinga <slouken@libsdl.org> parents: 1336 diff changeset	54 #define malloc SDL_malloc
c687f06c7473 Don't touch code that we brought in from other sources Sam Lantinga <slouken@libsdl.org> parents: 1336 diff changeset	55 #define free SDL_free
c687f06c7473 Don't touch code that we brought in from other sources Sam Lantinga <slouken@libsdl.org> parents: 1336 diff changeset	56 #define memcpy SDL_memcpy
c687f06c7473 Don't touch code that we brought in from other sources Sam Lantinga <slouken@libsdl.org> parents: 1336 diff changeset	57 #define memmove SDL_memmove
c687f06c7473 Don't touch code that we brought in from other sources Sam Lantinga <slouken@libsdl.org> parents: 1336 diff changeset	58 #define qsort SDL_qsort
c687f06c7473 Don't touch code that we brought in from other sources Sam Lantinga <slouken@libsdl.org> parents: 1336 diff changeset	59
c687f06c7473 Don't touch code that we brought in from other sources Sam Lantinga <slouken@libsdl.org> parents: 1336 diff changeset	60
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	61 #ifndef HAVE_QSORT
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	62
3162 dc1eb82ffdaa Von: Thomas Zimmermann Sam Lantinga <slouken@libsdl.org> parents: 1895 diff changeset	63 static const char _ID[] = "<qsort.c gjm 1.12 1998-03-19>";
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	64
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	65 /* How many bytes are there per word? (Must be a power of 2,
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	66 * and must in fact equal sizeof(int).)
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	67 */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	68 #define WORD_BYTES sizeof(int)
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	69
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	70 /* How big does our stack need to be? Answer: one entry per
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	71 * bit in a \|size_t\|.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	72 */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	73 #define STACK_SIZE (8*sizeof(size_t))
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	74
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	75 /* Different situations have slightly different requirements,
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	76 * and we make life epsilon easier by using different truncation
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	77 * points for the three different cases.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	78 * So far, I have tuned TRUNC_words and guessed that the same
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	79 * value might work well for the other two cases. Of course
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	80 * what works well on my machine might work badly on yours.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	81 */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	82 #define TRUNC_nonaligned 12
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	83 #define TRUNC_aligned 12
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	84 #define TRUNC_words 12WORD_BYTES / nb different meaning */
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	85
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	86 /* We use a simple pivoting algorithm for shortish sub-arrays
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	87 * and a more complicated one for larger ones. The threshold
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	88 * is PIVOT_THRESHOLD.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	89 */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	90 #define PIVOT_THRESHOLD 40
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	91
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	92 typedef struct
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	93 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	94 char *first;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	95 char *last;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	96 } stack_entry;
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	97 #define pushLeft {stack[stacktop].first=ffirst;stack[stacktop++].last=last;}
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	98 #define pushRight {stack[stacktop].first=first;stack[stacktop++].last=llast;}
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	99 #define doLeft {first=ffirst;llast=last;continue;}
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	100 #define doRight {ffirst=first;last=llast;continue;}
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	101 #define pop {if (--stacktop<0) break;\
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	102 first=ffirst=stack[stacktop].first;\
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	103 last=llast=stack[stacktop].last;\
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	104 continue;}
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	105
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	106 /* Some comments on the implementation.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	107 * 1. When we finish partitioning the array into "low"
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	108 * and "high", we forget entirely about short subarrays,
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	109 * because they'll be done later by insertion sort.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	110 * Doing lots of little insertion sorts might be a win
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	111 * on large datasets for locality-of-reference reasons,
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	112 * but it makes the code much nastier and increases
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	113 * bookkeeping overhead.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	114 * 2. We always save the shorter and get to work on the
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	115 * longer. This guarantees that every time we push
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	116 * an item onto the stack its size is <= 1/2 of that
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	117 * of its parent; so the stack can't need more than
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	118 * log_2(max-array-size) entries.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	119 * 3. We choose a pivot by looking at the first, last
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	120 * and middle elements. We arrange them into order
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	121 * because it's easy to do that in conjunction with
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	122 * choosing the pivot, and it makes things a little
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	123 * easier in the partitioning step. Anyway, the pivot
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	124 * is the middle of these three. It's still possible
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	125 * to construct datasets where the algorithm takes
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	126 * time of order n^2, but it simply never happens in
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	127 * practice.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	128 * 3' Newsflash: On further investigation I find that
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	129 * it's easy to construct datasets where median-of-3
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	130 * simply isn't good enough. So on large-ish subarrays
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	131 * we do a more sophisticated pivoting: we take three
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	132 * sets of 3 elements, find their medians, and then
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	133 * take the median of those.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	134 * 4. We copy the pivot element to a separate place
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	135 * because that way we can always do our comparisons
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	136 * directly against a pointer to that separate place,
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	137 * and don't have to wonder "did we move the pivot
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	138 * element?". This makes the inner loop better.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	139 * 5. It's possible to make the pivoting even more
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	140 * reliable by looking at more candidates when n
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	141 * is larger. (Taking this to its logical conclusion
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	142 * results in a variant of quicksort that doesn't
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	143 * have that n^2 worst case.) However, the overhead
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	144 * from the extra bookkeeping means that it's just
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	145 * not worth while.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	146 * 6. This is pretty clean and portable code. Here are
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	147 * all the potential portability pitfalls and problems
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	148 * I know of:
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	149 * - In one place (the insertion sort) I construct
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	150 * a pointer that points just past the end of the
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	151 * supplied array, and assume that (a) it won't
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	152 * compare equal to any pointer within the array,
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	153 * and (b) it will compare equal to a pointer
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	154 * obtained by stepping off the end of the array.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	155 * These might fail on some segmented architectures.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	156 * - I assume that there are 8 bits in a \|char\| when
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	157 * computing the size of stack needed. This would
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	158 * fail on machines with 9-bit or 16-bit bytes.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	159 * - I assume that if \|((int)base&(sizeof(int)-1))==0\|
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	160 * and \|(size&(sizeof(int)-1))==0\| then it's safe to
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	161 * get at array elements via \|int*\|s, and that if
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	162 * actually \|size==sizeof(int)\| as well then it's
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	163 * safe to treat the elements as \|int\|s. This might
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	164 * fail on systems that convert pointers to integers
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	165 * in non-standard ways.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	166 * - I assume that \|8*sizeof(size_t)<=INT_MAX\|. This
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	167 * would be false on a machine with 8-bit \|char\|s,
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	168 * 16-bit \|int\|s and 4096-bit \|size_t\|s. :-)
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	169 */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	170
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	171 /* The recursion logic is the same in each case: */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	172 #define Recurse(Trunc) \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	173 { size_t l=last-ffirst,r=llast-first; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	174 if (l<Trunc) { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	175 if (r>=Trunc) doRight \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	176 else pop \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	177 } \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	178 else if (l<=r) { pushLeft; doRight } \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	179 else if (r>=Trunc) { pushRight; doLeft }\
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	180 else doLeft \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	181 }
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	182
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	183 /* and so is the pivoting logic: */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	184 #define Pivot(swapper,sz) \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	185 if ((size_t)(last-first)>PIVOT_THRESHOLD*sz) mid=pivot_big(first,mid,last,sz,compare);\
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	186 else { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	187 if (compare(first,mid)<0) { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	188 if (compare(mid,last)>0) { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	189 swapper(mid,last); \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	190 if (compare(first,mid)>0) swapper(first,mid);\
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	191 } \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	192 } \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	193 else { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	194 if (compare(mid,last)>0) swapper(first,last)\
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	195 else { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	196 swapper(first,mid); \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	197 if (compare(mid,last)>0) swapper(mid,last);\
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	198 } \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	199 } \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	200 first+=sz; last-=sz; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	201 }
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	202
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	203 #ifdef DEBUG_QSORT
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	204 #include <stdio.h>
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	205 #endif
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	206
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	207 /* and so is the partitioning logic: */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	208 #define Partition(swapper,sz) { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	209 int swapped=0; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	210 do { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	211 while (compare(first,pivot)<0) first+=sz; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	212 while (compare(pivot,last)<0) last-=sz; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	213 if (first<last) { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	214 swapper(first,last); swapped=1; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	215 first+=sz; last-=sz; } \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	216 else if (first==last) { first+=sz; last-=sz; break; }\
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	217 } while (first<=last); \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	218 if (!swapped) pop \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	219 }
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	220
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	221 /* and so is the pre-insertion-sort operation of putting
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	222 * the smallest element into place as a sentinel.
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	223 * Doing this makes the inner loop nicer. I got this
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	224 * idea from the GNU implementation of qsort().
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	225 */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	226 #define PreInsertion(swapper,limit,sz) \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	227 first=base; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	228 last=first + (nmemb>limit ? limit : nmemb-1)*sz;\
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	229 while (last!=base) { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	230 if (compare(first,last)>0) first=last; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	231 last-=sz; } \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	232 if (first!=base) swapper(first,(char*)base);
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	233
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	234 /* and so is the insertion sort, in the first two cases: */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	235 #define Insertion(swapper) \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	236 last=((char)base)+nmembsize; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	237 for (first=((char*)base)+size;first!=last;first+=size) { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	238 char *test; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	239 /* Find the right place for \|first\|. \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	240 * My apologies for var reuse. */ \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	241 for (test=first-size;compare(test,first)>0;test-=size) ; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	242 test+=size; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	243 if (test!=first) { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	244 /* Shift everything in [test,first) \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	245 * up by one, and place \|first\| \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	246 * where \|test\| is. */ \
1337 c687f06c7473 Don't touch code that we brought in from other sources Sam Lantinga <slouken@libsdl.org> parents: 1336 diff changeset	247 memcpy(pivot,first,size); \
c687f06c7473 Don't touch code that we brought in from other sources Sam Lantinga <slouken@libsdl.org> parents: 1336 diff changeset	248 memmove(test+size,test,first-test); \
c687f06c7473 Don't touch code that we brought in from other sources Sam Lantinga <slouken@libsdl.org> parents: 1336 diff changeset	249 memcpy(test,pivot,size); \
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	250 } \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	251 }
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	252
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	253 #define SWAP_nonaligned(a,b) { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	254 register char aa=(a),bb=(b); \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	255 register size_t sz=size; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	256 do { register char t=aa; aa++=bb; bb++=t; } while (--sz); }
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	257
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	258 #define SWAP_aligned(a,b) { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	259 register int aa=(int)(a),bb=(int)(b); \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	260 register size_t sz=size; \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	261 do { register int t=aa;aa++=bb; bb++=t; } while (sz-=WORD_BYTES); }
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	262
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	263 #define SWAP_words(a,b) { \
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	264 register int t=((int)a); ((int)a)=((int)b); ((int)b)=t; }
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	265
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	266 /* ---------------------------------------------------------------------- */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	267
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	268 static char *
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	269 pivot_big(char first, char mid, char *last, size_t size,
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	270 int compare(const void , const void ))
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	271 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	272 size_t d = (((last - first) / size) >> 3) * size;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	273 char m1, m2, *m3;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	274 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	275 char a = first, b = first + d, c = first + 2 d;
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	276 #ifdef DEBUG_QSORT
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	277 fprintf(stderr, "< %d %d %d\n", (int ) a, (int ) b, (int ) c);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	278 #endif
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	279 m1 = compare(a, b) < 0 ?
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	280 (compare(b, c) < 0 ? b : (compare(a, c) < 0 ? c : a))
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	281 : (compare(a, c) < 0 ? a : (compare(b, c) < 0 ? c : b));
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	282 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	283 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	284 char a = mid - d, b = mid, *c = mid + d;
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	285 #ifdef DEBUG_QSORT
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	286 fprintf(stderr, ". %d %d %d\n", (int ) a, (int ) b, (int ) c);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	287 #endif
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	288 m2 = compare(a, b) < 0 ?
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	289 (compare(b, c) < 0 ? b : (compare(a, c) < 0 ? c : a))
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	290 : (compare(a, c) < 0 ? a : (compare(b, c) < 0 ? c : b));
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	291 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	292 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	293 char a = last - 2 d, b = last - d, c = last;
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	294 #ifdef DEBUG_QSORT
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	295 fprintf(stderr, "> %d %d %d\n", (int ) a, (int ) b, (int ) c);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	296 #endif
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	297 m3 = compare(a, b) < 0 ?
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	298 (compare(b, c) < 0 ? b : (compare(a, c) < 0 ? c : a))
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	299 : (compare(a, c) < 0 ? a : (compare(b, c) < 0 ? c : b));
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	300 }
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	301 #ifdef DEBUG_QSORT
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	302 fprintf(stderr, "-> %d %d %d\n", (int ) m1, (int ) m2, (int ) m3);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	303 #endif
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	304 return compare(m1, m2) < 0 ?
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	305 (compare(m2, m3) < 0 ? m2 : (compare(m1, m3) < 0 ? m3 : m1))
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	306 : (compare(m1, m3) < 0 ? m1 : (compare(m2, m3) < 0 ? m3 : m2));
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	307 }
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	308
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	309 /* ---------------------------------------------------------------------- */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	310
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	311 static void
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	312 qsort_nonaligned(void *base, size_t nmemb, size_t size,
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	313 int (compare) (const void , const void *))
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	314 {
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	315
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	316 stack_entry stack[STACK_SIZE];
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	317 int stacktop = 0;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	318 char first, last;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	319 char *pivot = malloc(size);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	320 size_t trunc = TRUNC_nonaligned * size;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	321 assert(pivot != 0);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	322
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	323 first = (char *) base;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	324 last = first + (nmemb - 1) * size;
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	325
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	326 if ((size_t) (last - first) > trunc) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	327 char ffirst = first, llast = last;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	328 while (1) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	329 /* Select pivot */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	330 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	331 char mid = first + size ((last - first) / size >> 1);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	332 Pivot(SWAP_nonaligned, size);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	333 memcpy(pivot, mid, size);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	334 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	335 /* Partition. */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	336 Partition(SWAP_nonaligned, size);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	337 /* Prepare to recurse/iterate. */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	338 Recurse(trunc)}
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	339 }
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	340 PreInsertion(SWAP_nonaligned, TRUNC_nonaligned, size);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	341 Insertion(SWAP_nonaligned);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	342 free(pivot);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	343 }
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	344
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	345 static void
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	346 qsort_aligned(void *base, size_t nmemb, size_t size,
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	347 int (compare) (const void , const void *))
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	348 {
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	349
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	350 stack_entry stack[STACK_SIZE];
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	351 int stacktop = 0;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	352 char first, last;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	353 char *pivot = malloc(size);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	354 size_t trunc = TRUNC_aligned * size;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	355 assert(pivot != 0);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	356
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	357 first = (char *) base;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	358 last = first + (nmemb - 1) * size;
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	359
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	360 if ((size_t) (last - first) > trunc) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	361 char ffirst = first, llast = last;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	362 while (1) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	363 /* Select pivot */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	364 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	365 char mid = first + size ((last - first) / size >> 1);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	366 Pivot(SWAP_aligned, size);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	367 memcpy(pivot, mid, size);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	368 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	369 /* Partition. */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	370 Partition(SWAP_aligned, size);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	371 /* Prepare to recurse/iterate. */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	372 Recurse(trunc)}
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	373 }
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	374 PreInsertion(SWAP_aligned, TRUNC_aligned, size);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	375 Insertion(SWAP_aligned);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	376 free(pivot);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	377 }
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	378
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	379 static void
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	380 qsort_words(void *base, size_t nmemb,
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	381 int (compare) (const void , const void *))
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	382 {
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	383
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	384 stack_entry stack[STACK_SIZE];
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	385 int stacktop = 0;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	386 char first, last;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	387 char *pivot = malloc(WORD_BYTES);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	388 assert(pivot != 0);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	389
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	390 first = (char *) base;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	391 last = first + (nmemb - 1) * WORD_BYTES;
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	392
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	393 if (last - first > TRUNC_words) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	394 char ffirst = first, llast = last;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	395 while (1) {
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	396 #ifdef DEBUG_QSORT
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	397 fprintf(stderr, "Doing %d:%d: ",
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	398 (first - (char *) base) / WORD_BYTES,
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	399 (last - (char *) base) / WORD_BYTES);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	400 #endif
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	401 /* Select pivot */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	402 {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	403 char *mid =
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	404 first + WORD_BYTES * ((last - first) / (2 * WORD_BYTES));
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	405 Pivot(SWAP_words, WORD_BYTES);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	406 (int ) pivot = (int ) mid;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	407 }
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	408 #ifdef DEBUG_QSORT
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	409 fprintf(stderr, "pivot=%d\n", (int ) pivot);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	410 #endif
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	411 /* Partition. */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	412 Partition(SWAP_words, WORD_BYTES);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	413 /* Prepare to recurse/iterate. */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	414 Recurse(TRUNC_words)}
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	415 }
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	416 PreInsertion(SWAP_words, (TRUNC_words / WORD_BYTES), WORD_BYTES);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	417 /* Now do insertion sort. */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	418 last = ((char ) base) + nmemb WORD_BYTES;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	419 for (first = ((char *) base) + WORD_BYTES; first != last;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	420 first += WORD_BYTES) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	421 /* Find the right place for \|first\|. My apologies for var reuse */
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	422 int pl = (int ) (first - WORD_BYTES), pr = (int ) first;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	423 (int ) pivot = (int ) first;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	424 for (; compare(pl, pivot) > 0; pr = pl, --pl) {
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	425 pr = pl;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	426 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	427 if (pr != (int *) first)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	428 pr = (int *) pivot;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	429 }
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	430 free(pivot);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	431 }
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	432
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	433 /* ---------------------------------------------------------------------- */
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	434
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	435 void
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	436 qsort(void *base, size_t nmemb, size_t size,
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	437 int (compare) (const void , const void *))
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	438 {
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	439
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	440 if (nmemb <= 1)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	441 return;
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	442 if (((uintptr_t) base \| size) & (WORD_BYTES - 1))
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	443 qsort_nonaligned(base, nmemb, size, compare);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	444 else if (size != WORD_BYTES)
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	445 qsort_aligned(base, nmemb, size, compare);
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	446 else
c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	447 qsort_words(base, nmemb, compare);
1330 450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	448 }
450721ad5436 It's now possible to build SDL without any C runtime at all on Windows, Sam Lantinga <slouken@libsdl.org> parents: diff changeset	449
1331 1cbaeee565b1 A few fixes to get this building on Linux again Sam Lantinga <slouken@libsdl.org> parents: 1330 diff changeset	450 #endif /* !HAVE_QSORT */
1895 c121d94672cb SDL 1.2 is moving to a branch, and SDL 1.3 is becoming the head. Sam Lantinga <slouken@libsdl.org> parents: 1456 diff changeset	451 /* vi: set ts=4 sw=4 expandtab: */

Mercurial > sdl-ios-xcode

annotate src/stdlib/SDL_qsort.c @ 3476:ab99313951cd