1 /* This code in included by number.s.c to generate integer conversion
2 functions like scm_to_int and scm_from_int. It is only for
3 unsigned types, see conv-integer.i.c for the signed variant.
6 /* You need to define the following macros before including this
7 template. They are undefined at the end of this file to giove a
8 clean slate for the next inclusion.
10 TYPE - the integral type to be converted
11 TYPE_MIN - the smallest representable number of TYPE, typically 0.
12 TYPE_MAX - the largest representable number of TYPE
13 SIZEOF_TYPE - the size of TYPE, equal to "sizeof (TYPE)" but
14 in a form that can be computed by the preprocessor.
15 When this number is 0, the preprocessor is not used
16 to select which code to compile; the most general
19 SCM_TO_TYPE_PROTO(arg), SCM_FROM_TYPE_PROTO(arg)
20 - These two macros should expand into the prototype
21 for the two defined functions, without the return
27 SCM_TO_TYPE_PROTO (SCM val)
29 if (SCM_I_INUMP (val))
31 scm_t_signed_bits n = SCM_I_INUM (val);
33 && ((scm_t_uintmax)n) >= TYPE_MIN && ((scm_t_uintmax)n) <= TYPE_MAX)
38 scm_i_range_error (val,
39 scm_from_unsigned_integer (TYPE_MIN),
40 scm_from_unsigned_integer (TYPE_MAX));
44 else if (SCM_BIGP (val))
46 if (TYPE_MAX <= SCM_MOST_POSITIVE_FIXNUM)
48 else if (TYPE_MAX <= ULONG_MAX)
50 if (mpz_fits_ulong_p (SCM_I_BIG_MPZ (val)))
52 unsigned long n = mpz_get_ui (SCM_I_BIG_MPZ (val));
53 #if SIZEOF_TYPE != 0 && SIZEOF_TYPE > SCM_SIZEOF_LONG
56 if (n >= TYPE_MIN && n <= TYPE_MAX)
70 if (mpz_sgn (SCM_I_BIG_MPZ (val)) < 0)
73 if (mpz_sizeinbase (SCM_I_BIG_MPZ (val), 2)
74 > CHAR_BIT*sizeof (TYPE))
77 mpz_export (&n, &count, 1, sizeof (TYPE), 0, 0, SCM_I_BIG_MPZ (val));
79 if (n >= TYPE_MIN && n <= TYPE_MAX)
87 scm_wrong_type_arg_msg (NULL, 0, val, "exact integer");
93 SCM_FROM_TYPE_PROTO (TYPE val)
95 #if SIZEOF_TYPE != 0 && SIZEOF_TYPE < SIZEOF_SCM_T_BITS
96 return SCM_I_MAKINUM (val);
98 if (SCM_POSFIXABLE (val))
99 return SCM_I_MAKINUM (val);
100 else if (val <= ULONG_MAX)
101 return scm_i_ulong2big (val);
104 SCM z = scm_double_cell (scm_tc16_big, 0, 0, 0);
105 mpz_init (SCM_I_BIG_MPZ (z));
106 mpz_import (SCM_I_BIG_MPZ (z), 1, 1, sizeof (TYPE), 0, 0, &val);
116 #undef SCM_TO_TYPE_PROTO
117 #undef SCM_FROM_TYPE_PROTO