1 /*
2 FUNCTION
3 <<ldiv>>---divide two long integers
4
5 INDEX
6 ldiv
7
8 SYNOPSIS
9 #include <stdlib.h>
10 ldiv_t ldiv(long <[n]>, long <[d]>);
11
12 DESCRIPTION
13 Divide
14 @tex
15 $n/d$,
16 @end tex
17 @ifnottex
18 <[n]>/<[d]>,
19 @end ifnottex
20 returning quotient and remainder as two long integers in a structure <<ldiv_t>>.
21
22 RETURNS
23 The result is represented with the structure
24
25 . typedef struct
26 . {
27 . long quot;
28 . long rem;
29 . } ldiv_t;
30
31 where the <<quot>> field represents the quotient, and <<rem>> the
32 remainder. For nonzero <[d]>, if `<<<[r]> = ldiv(<[n]>,<[d]>);>>' then
33 <[n]> equals `<<<[r]>.rem + <[d]>*<[r]>.quot>>'.
34
35 To divide <<int>> rather than <<long>> values, use the similar
36 function <<div>>.
37
38 PORTABILITY
39 <<ldiv>> is ANSI.
40
41 No supporting OS subroutines are required.
42 */
43
44
45 /*
46 * Copyright (c) 1990 Regents of the University of California.
47 * All rights reserved.
48 *
49 * This code is derived from software contributed to Berkeley by
50 * Chris Torek.
51 *
52 * Redistribution and use in source and binary forms, with or without
53 * modification, are permitted provided that the following conditions
54 * are met:
55 * 1. Redistributions of source code must retain the above copyright
56 * notice, this list of conditions and the following disclaimer.
57 * 2. Redistributions in binary form must reproduce the above copyright
58 * notice, this list of conditions and the following disclaimer in the
59 * documentation and/or other materials provided with the distribution.
60 * 3. Neither the name of the University nor the names of its contributors
61 * may be used to endorse or promote products derived from this software
62 * without specific prior written permission.
63 *
64 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
65 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
66 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
67 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
68 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
69 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
70 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
71 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
72 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
73 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
74 * SUCH DAMAGE.
75 */
76
77 #include <_ansi.h>
78 #include <stdlib.h> /* ldiv_t */
79
80 ldiv_t
ldiv(long num,long denom)81 ldiv (long num,
82 long denom)
83 {
84 ldiv_t r;
85
86 /* see div.c for comments */
87
88 r.quot = num / denom;
89 r.rem = num % denom;
90 if (num >= 0 && r.rem < 0) {
91 ++r.quot;
92 r.rem -= denom;
93 }
94 else if (num < 0 && r.rem > 0) {
95 --r.quot;
96 r.rem += denom;
97 }
98 return (r);
99 }
100
