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comparison libtommath/bn_mp_toradix_n.c @ 435:337c45621e81

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merge of 'a9b0496634cdd25647b65e585cc3240f3fa699ee' and 'c22be8b8f570b48e9662dac32c7b3e7148a42206'
author Matt Johnston <matt@ucc.asn.au>
date Thu, 22 Feb 2007 14:53:49 +0000
parents 5ff8218bcee9
children 60fc6476e044
comparison
equal deleted inserted replaced
434:0aaaf68e97dc 435:337c45621e81
10 * additional optimizations in place. 10 * additional optimizations in place.
11 * 11 *
12 * The library is free for all purposes without any express 12 * The library is free for all purposes without any express
13 * guarantee it works. 13 * guarantee it works.
14 * 14 *
15 * Tom St Denis, [email protected], http://math.libtomcrypt.org 15 * Tom St Denis, [email protected], http://math.libtomcrypt.com
16 */ 16 */
17 17
18 /* stores a bignum as a ASCII string in a given radix (2..64) 18 /* stores a bignum as a ASCII string in a given radix (2..64)
19 * 19 *
20 * Stores upto maxlen-1 chars and always a NULL byte 20 * Stores upto maxlen-1 chars and always a NULL byte
25 mp_int t; 25 mp_int t;
26 mp_digit d; 26 mp_digit d;
27 char *_s = str; 27 char *_s = str;
28 28
29 /* check range of the maxlen, radix */ 29 /* check range of the maxlen, radix */
30 if (maxlen < 3 || radix < 2 || radix > 64) { 30 if (maxlen < 2 || radix < 2 || radix > 64) {
31 return MP_VAL; 31 return MP_VAL;
32 } 32 }
33 33
34 /* quick out if its zero */ 34 /* quick out if its zero */
35 if (mp_iszero(a) == 1) { 35 if (mp_iszero(a) == MP_YES) {
36 *str++ = '0'; 36 *str++ = '0';
37 *str = '\0'; 37 *str = '\0';
38 return MP_OKAY; 38 return MP_OKAY;
39 } 39 }
40 40
55 --maxlen; 55 --maxlen;
56 } 56 }
57 57
58 digs = 0; 58 digs = 0;
59 while (mp_iszero (&t) == 0) { 59 while (mp_iszero (&t) == 0) {
60 if (--maxlen < 1) {
61 /* no more room */
62 break;
63 }
60 if ((res = mp_div_d (&t, (mp_digit) radix, &t, &d)) != MP_OKAY) { 64 if ((res = mp_div_d (&t, (mp_digit) radix, &t, &d)) != MP_OKAY) {
61 mp_clear (&t); 65 mp_clear (&t);
62 return res; 66 return res;
63 } 67 }
64 *str++ = mp_s_rmap[d]; 68 *str++ = mp_s_rmap[d];
65 ++digs; 69 ++digs;
66
67 if (--maxlen == 1) {
68 /* no more room */
69 break;
70 }
71 } 70 }
72 71
73 /* reverse the digits of the string. In this case _s points 72 /* reverse the digits of the string. In this case _s points
74 * to the first digit [exluding the sign] of the number] 73 * to the first digit [exluding the sign] of the number
75 */ 74 */
76 bn_reverse ((unsigned char *)_s, digs); 75 bn_reverse ((unsigned char *)_s, digs);
77 76
78 /* append a NULL so the string is properly terminated */ 77 /* append a NULL so the string is properly terminated */
79 *str = '\0'; 78 *str = '\0';
81 mp_clear (&t); 80 mp_clear (&t);
82 return MP_OKAY; 81 return MP_OKAY;
83 } 82 }
84 83
85 #endif 84 #endif
85
86 /* $Source: /cvs/libtom/libtommath/bn_mp_toradix_n.c,v $ */
87 /* $Revision: 1.4 $ */
88 /* $Date: 2006/03/31 14:18:44 $ */