Mercurial > sdl-ios-xcode
annotate src/stdlib/SDL_qsort.c @ 3230:816a7a65a59a
Fixed compiling SDL_fsaudio.c against fusionsound 1.0.0
author | Couriersud <couriersud@arcor.de> |
---|---|
date | Mon, 03 Aug 2009 18:07:31 +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 | 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 12*WORD_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)+nmemb*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
|
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: */ |