1/* _mpq_cmp_si -- compare mpq and long/ulong fraction.
2
3Copyright 2001, 2013, 2014 Free Software Foundation, Inc.
4
5This file is part of the GNU MP Library.
6
7The GNU MP Library is free software; you can redistribute it and/or modify
8it under the terms of either:
9
10  * the GNU Lesser General Public License as published by the Free
11    Software Foundation; either version 3 of the License, or (at your
12    option) any later version.
13
14or
15
16  * the GNU General Public License as published by the Free Software
17    Foundation; either version 2 of the License, or (at your option) any
18    later version.
19
20or both in parallel, as here.
21
22The GNU MP Library is distributed in the hope that it will be useful, but
23WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
24or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
25for more details.
26
27You should have received copies of the GNU General Public License and the
28GNU Lesser General Public License along with the GNU MP Library.  If not,
29see https://www.gnu.org/licenses/.  */
30
31#include "gmp-impl.h"
32
33
34/* Something like mpq_cmpabs_ui would be more useful for the neg/neg case,
35   and perhaps a version accepting a parameter to reverse the test, to make
36   it a tail call here.  */
37
38int
39_mpq_cmp_si (mpq_srcptr q, long n, unsigned long d)
40{
41  /* need canonical sign to get right result */
42  ASSERT (SIZ(DEN(q)) > 0);
43
44  if (n >= 0)
45    return _mpq_cmp_ui (q, n, d);
46  if (SIZ(NUM(q)) >= 0)
47    {
48      return 1;                                /* >=0 cmp <0 */
49    }
50  else
51    {
52      mpq_t  qabs;
53      SIZ(NUM(qabs)) = -SIZ(NUM(q));
54      PTR(NUM(qabs)) = PTR(NUM(q));
55      SIZ(DEN(qabs)) = SIZ(DEN(q));
56      PTR(DEN(qabs)) = PTR(DEN(q));
57
58      return - _mpq_cmp_ui (qabs, NEG_CAST (unsigned long, n), d);    /* <0 cmp <0 */
59    }
60}
61