Commit | Line | Data |
6fe26b29 |
1 | package DBM::Deep::Array; |
2 | |
3 | use strict; |
4 | |
5 | use base 'DBM::Deep'; |
6 | |
596e9574 |
7 | sub _get_self { |
8 | eval { tied( @{$_[0]} ) } || $_[0] |
9 | } |
10 | |
6fe26b29 |
11 | sub TIEARRAY { |
12 | ## |
13 | # Tied array constructor method, called by Perl's tie() function. |
14 | ## |
15 | my $class = shift; |
16 | my $args; |
17 | if (scalar(@_) > 1) { $args = {@_}; } |
18 | #XXX This use of ref() is bad and is a bug |
19 | elsif (ref($_[0])) { $args = $_[0]; } |
20 | else { $args = { file => shift }; } |
21 | |
22 | $args->{type} = $class->TYPE_ARRAY; |
23 | |
24 | return $class->_init($args); |
25 | } |
26 | |
27 | ## |
28 | # The following methods are for arrays only |
29 | ## |
30 | |
31 | sub FETCHSIZE { |
32 | ## |
33 | # Return the length of the array |
34 | ## |
2ac02042 |
35 | my $self = $_[0]->_get_self; |
6fe26b29 |
36 | |
37 | my $SAVE_FILTER = $self->root->{filter_fetch_value}; |
38 | $self->root->{filter_fetch_value} = undef; |
39 | |
40 | my $packed_size = $self->FETCH('length'); |
41 | |
42 | $self->root->{filter_fetch_value} = $SAVE_FILTER; |
43 | |
44 | if ($packed_size) { return int(unpack($DBM::Deep::LONG_PACK, $packed_size)); } |
45 | else { return 0; } |
46 | } |
47 | |
48 | sub STORESIZE { |
49 | ## |
50 | # Set the length of the array |
51 | ## |
2ac02042 |
52 | my $self = $_[0]->_get_self; |
6fe26b29 |
53 | my $new_length = $_[1]; |
54 | |
55 | my $SAVE_FILTER = $self->root->{filter_store_value}; |
56 | $self->root->{filter_store_value} = undef; |
57 | |
58 | my $result = $self->STORE('length', pack($DBM::Deep::LONG_PACK, $new_length)); |
59 | |
60 | $self->root->{filter_store_value} = $SAVE_FILTER; |
61 | |
62 | return $result; |
63 | } |
64 | |
65 | sub POP { |
66 | ## |
67 | # Remove and return the last element on the array |
68 | ## |
2ac02042 |
69 | my $self = $_[0]->_get_self; |
6fe26b29 |
70 | my $length = $self->FETCHSIZE(); |
71 | |
72 | if ($length) { |
73 | my $content = $self->FETCH( $length - 1 ); |
74 | $self->DELETE( $length - 1 ); |
75 | return $content; |
76 | } |
77 | else { |
78 | return; |
79 | } |
80 | } |
81 | |
82 | sub PUSH { |
83 | ## |
84 | # Add new element(s) to the end of the array |
85 | ## |
2ac02042 |
86 | my $self = shift->_get_self; |
6fe26b29 |
87 | my $length = $self->FETCHSIZE(); |
88 | |
89 | while (my $content = shift @_) { |
90 | $self->STORE( $length, $content ); |
91 | $length++; |
92 | } |
93 | } |
94 | |
95 | sub SHIFT { |
96 | ## |
97 | # Remove and return first element on the array. |
98 | # Shift over remaining elements to take up space. |
99 | ## |
2ac02042 |
100 | my $self = $_[0]->_get_self; |
6fe26b29 |
101 | my $length = $self->FETCHSIZE(); |
102 | |
103 | if ($length) { |
104 | my $content = $self->FETCH( 0 ); |
105 | |
106 | ## |
107 | # Shift elements over and remove last one. |
108 | ## |
109 | for (my $i = 0; $i < $length - 1; $i++) { |
110 | $self->STORE( $i, $self->FETCH($i + 1) ); |
111 | } |
112 | $self->DELETE( $length - 1 ); |
113 | |
114 | return $content; |
115 | } |
116 | else { |
117 | return; |
118 | } |
119 | } |
120 | |
121 | sub UNSHIFT { |
122 | ## |
123 | # Insert new element(s) at beginning of array. |
124 | # Shift over other elements to make space. |
125 | ## |
2ac02042 |
126 | my $self = shift->_get_self; |
6fe26b29 |
127 | my @new_elements = @_; |
128 | my $length = $self->FETCHSIZE(); |
129 | my $new_size = scalar @new_elements; |
130 | |
131 | if ($length) { |
132 | for (my $i = $length - 1; $i >= 0; $i--) { |
133 | $self->STORE( $i + $new_size, $self->FETCH($i) ); |
134 | } |
135 | } |
136 | |
137 | for (my $i = 0; $i < $new_size; $i++) { |
138 | $self->STORE( $i, $new_elements[$i] ); |
139 | } |
140 | } |
141 | |
142 | sub SPLICE { |
143 | ## |
144 | # Splices section of array with optional new section. |
145 | # Returns deleted section, or last element deleted in scalar context. |
146 | ## |
2ac02042 |
147 | my $self = shift->_get_self; |
6fe26b29 |
148 | my $length = $self->FETCHSIZE(); |
149 | |
150 | ## |
151 | # Calculate offset and length of splice |
152 | ## |
153 | my $offset = shift || 0; |
154 | if ($offset < 0) { $offset += $length; } |
155 | |
156 | my $splice_length; |
157 | if (scalar @_) { $splice_length = shift; } |
158 | else { $splice_length = $length - $offset; } |
159 | if ($splice_length < 0) { $splice_length += ($length - $offset); } |
160 | |
161 | ## |
162 | # Setup array with new elements, and copy out old elements for return |
163 | ## |
164 | my @new_elements = @_; |
165 | my $new_size = scalar @new_elements; |
166 | |
167 | my @old_elements = (); |
168 | for (my $i = $offset; $i < $offset + $splice_length; $i++) { |
169 | push @old_elements, $self->FETCH( $i ); |
170 | } |
171 | |
172 | ## |
173 | # Adjust array length, and shift elements to accomodate new section. |
174 | ## |
175 | if ( $new_size != $splice_length ) { |
176 | if ($new_size > $splice_length) { |
177 | for (my $i = $length - 1; $i >= $offset + $splice_length; $i--) { |
178 | $self->STORE( $i + ($new_size - $splice_length), $self->FETCH($i) ); |
179 | } |
180 | } |
181 | else { |
182 | for (my $i = $offset + $splice_length; $i < $length; $i++) { |
183 | $self->STORE( $i + ($new_size - $splice_length), $self->FETCH($i) ); |
184 | } |
185 | for (my $i = 0; $i < $splice_length - $new_size; $i++) { |
186 | $self->DELETE( $length - 1 ); |
187 | $length--; |
188 | } |
189 | } |
190 | } |
191 | |
192 | ## |
193 | # Insert new elements into array |
194 | ## |
195 | for (my $i = $offset; $i < $offset + $new_size; $i++) { |
196 | $self->STORE( $i, shift @new_elements ); |
197 | } |
198 | |
199 | ## |
200 | # Return deleted section, or last element in scalar context. |
201 | ## |
202 | return wantarray ? @old_elements : $old_elements[-1]; |
203 | } |
204 | |
205 | #XXX We don't need to define it. |
206 | #XXX It will be useful, though, when we split out HASH and ARRAY |
207 | #sub EXTEND { |
208 | ## |
209 | # Perl will call EXTEND() when the array is likely to grow. |
210 | # We don't care, but include it for compatibility. |
211 | ## |
212 | #} |
213 | |
214 | ## |
215 | # Public method aliases |
216 | ## |
217 | *length = *FETCHSIZE; |
218 | *pop = *POP; |
219 | *push = *PUSH; |
220 | *shift = *SHIFT; |
221 | *unshift = *UNSHIFT; |
222 | *splice = *SPLICE; |
223 | |
224 | 1; |
225 | __END__ |