blob: 069e7e3a4a11b505d654ab31a3b772c5f44b487d (
plain)
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
117
118
119
120
121
122
123
124
|
#-*- perl -*-
#
# Copyright (C) 2001 Ken'ichi Fukamachi
# All rights reserved. This program is free software; you can
# redistribute it and/or modify it under the same terms as Perl itself.
#
# $Id$
# $FML$
#
package Standalone;
use strict;
use Carp;
# Descriptions: load "key = value" style configuration.
# It is available to use the following style.
# key = value1 value2
# value3
# XXX This file is non-Object Oriented style but
# XXX this is minimum module used in standalone program.
# Arguments: $file $params
# $params is 'key1=value1 key2=value2' syntax.
# Side Effects: $config (hash reference) is allocated on memory here.
# Return Value: hash reference to configuration parameters
sub load_cf
{
my ($file, $params) = @_;
my $config = $params ? _parse_params($params) : {};
use FileHandle;
my $fh = new FileHandle $file;
if (defined $fh) {
my $curkey;
while (<$fh>) {
next if /^\#/;
chop;
if (/^([A-Za-z]\w+)\s+=\s*(.*)/) {
my ($key, $value) = ($1, $2);
$curkey = $key;
$config->{$key} = $value;
}
if (/^\s+(.*)/) {
$config->{ $curkey } .= " ". $1;
}
}
$fh->close;
}
else {
croak("Error: cannot open $file");
}
_expand_variables( $config );
return $config;
}
# Descriptions: expand $var to the value of $var.
# Arguments: $ref_to_config
# Side Effects: rewrite the given $config
# Return Value: none
sub _expand_variables
{
my ($config) = @_;
my @order = keys %$config;
# check whether the variable definition is recursive.
# For example, definition "var_a = $var_a/b/c" causes a loop.
for my $x ( @order ) {
if ($config->{ $x } =~ /\$$x/) {
croak("loop1: definition of $x is recursive\n");
}
}
# main expansion loop
my $org = '';
my $max = 0;
KEY:
for my $x ( @order ) {
next KEY if $config->{ $x } !~ /\$/o;
# we need a loop to expand nested variables, for example,
# a = $x/y and b = $a/c/0
#
$max = 0;
EXPANSION_LOOP:
while ($max++ < 16) {
$org = $config->{ $x };
$config->{ $x } =~ s/\$([a-z_]+)/$config->{$1}/g;
last EXPANSION_LOOP if $config->{ $x } !~ /\$/o;
last EXPANSION_LOOP if $org eq $config->{ $x };
if ($config->{ $x } =~ /\$$x/) {
croak("loop2: definition of $x is recursive\n");
}
}
if ($max >= 16) {
croak("variable expansion of $x causes infinite loop\n");
}
}
}
sub _parse_params
{
my ($params) = @_;
my %config = ();
for my $x (split(/\s+/, $params)) {
my ($key, $value) = split(/=/, $x);
$config{ $key } = $value;
}
\%config;
}
1;
|
