1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
|
/* eval-plural.c - Plural expression evaluation. */
/* Copyright (C) 2000-2002, 2006-2009 Free Software Foundation, Inc.
This file is part of GNU Bash.
Bash is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Bash is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Bash. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef STATIC
#define STATIC static
#endif
/* Evaluate the plural expression and return an index value. */
STATIC unsigned long int plural_eval PARAMS ((struct expression *pexp,
unsigned long int n))
internal_function;
STATIC
unsigned long int
internal_function
plural_eval (pexp, n)
struct expression *pexp;
unsigned long int n;
{
switch (pexp->nargs)
{
case 0:
switch (pexp->operation)
{
case var:
return n;
case num:
return pexp->val.num;
default:
break;
}
/* NOTREACHED */
break;
case 1:
{
/* pexp->operation must be lnot. */
unsigned long int arg = plural_eval (pexp->val.args[0], n);
return ! arg;
}
case 2:
{
unsigned long int leftarg = plural_eval (pexp->val.args[0], n);
if (pexp->operation == lor)
return leftarg || plural_eval (pexp->val.args[1], n);
else if (pexp->operation == land)
return leftarg && plural_eval (pexp->val.args[1], n);
else
{
unsigned long int rightarg = plural_eval (pexp->val.args[1], n);
switch (pexp->operation)
{
case mult:
return leftarg * rightarg;
case divide:
#if !INTDIV0_RAISES_SIGFPE
if (rightarg == 0)
raise (SIGFPE);
#endif
return leftarg / rightarg;
case module:
#if !INTDIV0_RAISES_SIGFPE
if (rightarg == 0)
raise (SIGFPE);
#endif
return leftarg % rightarg;
case plus:
return leftarg + rightarg;
case minus:
return leftarg - rightarg;
case less_than:
return leftarg < rightarg;
case greater_than:
return leftarg > rightarg;
case less_or_equal:
return leftarg <= rightarg;
case greater_or_equal:
return leftarg >= rightarg;
case equal:
return leftarg == rightarg;
case not_equal:
return leftarg != rightarg;
default:
break;
}
}
/* NOTREACHED */
break;
}
case 3:
{
/* pexp->operation must be qmop. */
unsigned long int boolarg = plural_eval (pexp->val.args[0], n);
return plural_eval (pexp->val.args[boolarg ? 1 : 2], n);
}
}
/* NOTREACHED */
return 0;
}
|