c4f2d992 |
1 | /* -*-c-*- |
2 | * |
3 | * $Id: set.c,v 1.1 1997/07/21 13:47:44 mdw Exp $ |
4 | * |
5 | * Management of sets (for the use of the class expression handler) |
6 | * |
7 | * (c) 1997 EBI |
8 | */ |
9 | |
10 | /*----- Licencing notice --------------------------------------------------* |
11 | * |
12 | * This file is part of `become' |
13 | * |
14 | * `Become' is free software; you can redistribute it and/or modify |
15 | * it under the terms of the GNU General Public License as published by |
16 | * the Free Software Foundation; either version 2 of the License, or |
17 | * (at your option) any later version. |
18 | * |
19 | * `Become' is distributed in the hope that it will be useful, |
20 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
21 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
22 | * GNU General Public License for more details. |
23 | * |
24 | * You should have received a copy of the GNU General Public License |
25 | * along with `become'; if not, write to the Free Software |
26 | * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
27 | */ |
28 | |
29 | /*----- Revision history --------------------------------------------------* |
30 | * |
31 | * $Log: set.c,v $ |
32 | * Revision 1.1 1997/07/21 13:47:44 mdw |
33 | * Initial revision |
34 | * |
35 | */ |
36 | |
37 | /*----- Header files ------------------------------------------------------*/ |
38 | |
39 | /* --- ANSI headers --- */ |
40 | |
41 | #include <stdio.h> |
42 | #include <stdlib.h> |
43 | #include <string.h> |
44 | |
45 | /* --- Local headers --- */ |
46 | |
47 | #include "set.h" |
48 | #include "sym.h" |
49 | #include "utils.h" |
50 | |
51 | /*----- Main code ---------------------------------------------------------*/ |
52 | |
53 | /* --- @set_subtract@ --- * |
54 | * |
55 | * Arguments: @sym_table *a@ = pointer to table @A@ |
56 | * @sym_table *b@ = pointer to table @B@ |
57 | * |
58 | * Returns: A symbol table containing all the elements in @A@ which don't |
59 | * appear in @B@. |
60 | * |
61 | * Use: Subtracts a symbol table from another symbol table. Assumes |
62 | * that there's no data following the actual @sym_base@ block |
63 | * for each item in the table. |
64 | */ |
65 | |
66 | sym_table *set_subtract(sym_table *a, sym_table *b) |
67 | { |
68 | sym_table *c = xmalloc(sizeof(*c)); |
69 | sym_iter i; |
70 | sym_base *s; |
71 | unsigned f; |
72 | |
73 | sym_createTable(c); |
74 | for (sym_createIter(&i, a); (s = sym_next(&i)) != 0; ) { |
75 | if (!sym_find(b, s->name, s->len, 0, &f)) |
76 | sym_find(c, s->name, s->len, sizeof(sym_base), 0); |
77 | } |
78 | |
79 | return (c); |
80 | } |
81 | |
82 | /* --- @set_intersect@ --- * |
83 | * |
84 | * Arguments: @sym_table *a@ = pointer to table @A@ |
85 | * @sym_table *b@ = pointer to table @B@ |
86 | * |
87 | * Returns: A symbol table containing all the elements in @A@ which also |
88 | * appear in @B@. |
89 | * |
90 | * Use: Constructs the intersection of two symbol tables. Assumes |
91 | * that there's no data following the actual @sym_base@ block |
92 | * for each item in the table. |
93 | */ |
94 | |
95 | sym_table *set_intersect(sym_table *a, sym_table *b) |
96 | { |
97 | sym_table *c = xmalloc(sizeof(*c)); |
98 | sym_iter i; |
99 | sym_base *s; |
100 | unsigned f; |
101 | |
102 | sym_createTable(c); |
103 | for (sym_createIter(&i, a); (s = sym_next(&i)) != 0; ) { |
104 | if (sym_find(b, s->name, s->len, 0, &f)) |
105 | sym_find(c, s->name, s->len, sizeof(sym_base), 0); |
106 | } |
107 | |
108 | return (c); |
109 | } |
110 | |
111 | /* --- @set_union@ --- * |
112 | * |
113 | * Arguments: @sym_table *a@ = pointer to table @A@ |
114 | * @sym_table *b@ = pointer to table @B@ |
115 | * |
116 | * Returns: A symbol table containing all the elements in @A@ and those |
117 | * in @B@. |
118 | * |
119 | * Use: Constructs the union of two symbol tables. Assumes that |
120 | * there's no data following the actual @sym_base@ block for |
121 | * each item in the table. |
122 | */ |
123 | |
124 | sym_table *set_union(sym_table *a, sym_table *b) |
125 | { |
126 | sym_table *c = xmalloc(sizeof(*c)); |
127 | sym_iter i; |
128 | sym_base *s; |
129 | |
130 | sym_createTable(c); |
131 | for (sym_createIter(&i, a); (s = sym_next(&i)) != 0; ) |
132 | sym_find(c, s->name, s->len, sizeof(sym_base), 0); |
133 | |
134 | for (sym_createIter(&i, b); (s = sym_next(&i)) != 0; ) |
135 | sym_find(c, s->name, s->len, sizeof(sym_base), 0); |
136 | |
137 | return (c); |
138 | } |
139 | |
140 | /* --- @set_copy@ --- * |
141 | * |
142 | * Arguments: @sym_table *a@ = pointer to table |
143 | * |
144 | * Returns: A copy of the symbol table. |
145 | * |
146 | * Use: Copies a symbol table. Same assumptions again... |
147 | */ |
148 | |
149 | sym_table *set_copy(sym_table *a) |
150 | { |
151 | sym_table *c = xmalloc(sizeof(*c)); |
152 | sym_iter i; |
153 | sym_base *s; |
154 | |
155 | for (sym_createIter(&i, a); (s = sym_next(&i)) != 0; ) |
156 | sym_find(c, s->name, s->len, sizeof(sym_base), 0); |
157 | |
158 | return (c); |
159 | } |
160 | |
161 | /*----- That's all, folks -------------------------------------------------*/ |