1 /* mpz_get_str (string, base, mp_src) -- Convert the multiple precision
2 number MP_SRC to a string STRING of base BASE. If STRING is NULL
3 allocate space for the result. In any case, return a pointer to the
4 result. If STRING is not NULL, the caller must ensure enough space is
5 available to store the result.
7 Copyright 1991, 1993, 1994, 1996, 2000, 2001, 2002, 2005 Free Software
10 This file is part of the GNU MP Library.
12 The GNU MP Library is free software; you can redistribute it and/or modify
13 it under the terms of the GNU Lesser General Public License as published by
14 the Free Software Foundation; either version 3 of the License, or (at your
15 option) any later version.
17 The GNU MP Library is distributed in the hope that it will be useful, but
18 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
19 or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
20 License for more details.
22 You should have received a copy of the GNU Lesser General Public License
23 along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */
25 #include <string.h> /* for strlen */
31 mpz_get_str (char *res_str
, int base
, mpz_srcptr x
)
34 mp_size_t x_size
= x
->_mp_size
;
38 size_t alloc_size
= 0;
45 num_to_text
= "0123456789abcdefghijklmnopqrstuvwxyz";
50 num_to_text
= "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
58 num_to_text
= "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
61 /* allocate string for the user if necessary */
64 /* digits, null terminator, possible minus sign */
65 MPN_SIZEINBASE (alloc_size
, PTR(x
), ABS(x_size
), base
);
66 alloc_size
+= 1 + (x_size
<0);
67 res_str
= (char *) (*__gmp_allocate_func
) (alloc_size
);
77 /* mpn_get_str clobbers its input on non power-of-2 bases */
82 xp
= TMP_ALLOC_LIMBS (x_size
+ 1); /* +1 in case x_size==0 */
83 MPN_COPY (xp
, x
->_mp_d
, x_size
);
86 str_size
= mpn_get_str ((unsigned char *) res_str
, base
, xp
, x_size
);
87 ASSERT (alloc_size
== 0 || str_size
<= alloc_size
- (SIZ(x
) < 0));
89 /* might have a leading zero, skip it */
91 if (*res_str
== 0 && str_size
!= 1)
95 ASSERT (*str
!= 0); /* at most one leading zero */
98 /* Convert result to printable chars, and move down if there was a leading
100 for (i
= 0; i
< str_size
; i
++)
101 res_str
[i
] = num_to_text
[(int) str
[i
]];
102 res_str
[str_size
] = 0;
106 /* if allocated then resize down to the actual space required */
109 size_t actual_size
= str_size
+ 1 + (res_str
- return_str
);
110 ASSERT (actual_size
== strlen (return_str
) + 1);
111 __GMP_REALLOCATE_FUNC_MAYBE_TYPE (return_str
, alloc_size
, actual_size
,