Commit | Line | Data |
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fecd2382 | 1 | /* bignum_copy.c - copy a bignum |
01170860 | 2 | Copyright (C) 1987, 1990, 1991, 1992 Free Software Foundation, Inc. |
a39116f1 RP |
3 | |
4 | This file is part of GAS, the GNU Assembler. | |
5 | ||
6 | GAS is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 2, or (at your option) | |
9 | any later version. | |
10 | ||
11 | GAS is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GAS; see the file COPYING. If not, write to | |
18 | the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */ | |
fecd2382 | 19 | |
fecd2382 RP |
20 | #include "as.h" |
21 | ||
22 | #ifdef USG | |
23 | #define bzero(s,n) memset(s,0,n) | |
24 | #define bcopy(from,to,n) memcpy(to,from,n) | |
25 | #endif | |
26 | ||
27 | /* | |
28 | * bignum_copy () | |
29 | * | |
30 | * Copy a bignum from in to out. | |
31 | * If the output is shorter than the input, copy lower-order littlenums. | |
32 | * Return 0 or the number of significant littlenums dropped. | |
33 | * Assumes littlenum arrays are densely packed: no unused chars between | |
34 | * the littlenums. Uses bcopy() to move littlenums, and wants to | |
35 | * know length (in chars) of the input bignum. | |
36 | */ | |
37 | ||
38 | /* void */ | |
39 | int | |
a39116f1 RP |
40 | bignum_copy (in, in_length, out, out_length) |
41 | register LITTLENUM_TYPE * in; | |
42 | register int in_length; /* in sizeof(littlenum)s */ | |
43 | register LITTLENUM_TYPE * out; | |
44 | register int out_length; /* in sizeof(littlenum)s */ | |
fecd2382 | 45 | { |
a39116f1 RP |
46 | register int significant_littlenums_dropped; |
47 | ||
48 | if (out_length < in_length) | |
49 | { | |
50 | register LITTLENUM_TYPE * p; /* -> most significant (non-zero) input littlenum. */ | |
51 | ||
52 | bcopy ((char *)in, (char *)out, out_length << LITTLENUM_SHIFT); | |
53 | for (p = in + in_length - 1; p >= in; -- p) | |
54 | { | |
55 | if (* p) break; | |
56 | } | |
57 | significant_littlenums_dropped = p - in - in_length + 1; | |
58 | if (significant_littlenums_dropped < 0) | |
59 | { | |
60 | significant_littlenums_dropped = 0; | |
61 | } | |
62 | } | |
63 | else | |
64 | { | |
65 | bcopy ((char *)in, (char *)out, in_length << LITTLENUM_SHIFT); | |
66 | if (out_length > in_length) | |
67 | { | |
68 | bzero ((char *)(out + out_length), (out_length - in_length) << LITTLENUM_SHIFT); | |
69 | } | |
70 | significant_littlenums_dropped = 0; | |
71 | } | |
72 | return (significant_littlenums_dropped); | |
fecd2382 RP |
73 | } |
74 | ||
a39116f1 | 75 | /* end of bignum-copy.c */ |