1/*-
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Kenneth Almquist.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 3. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#include <sys/param.h>
34#include <stdlib.h>
35#include <stddef.h>
36/*
37 * Routine for dealing with parsed shell commands.
38 */
39
40#include "shell.h"
41#include "nodes.h"
42#include "memalloc.h"
43#include "mystring.h"
44
45
46struct nodesize {
47 int blocksize; /* size of structures in function */
48 int stringsize; /* size of strings in node */
49};
50
51struct nodecopystate {
52 pointer block; /* block to allocate function from */
53 char *string; /* block to allocate strings from */
54};
55
56%SIZES
57
58
59static void calcsize(union node *, struct nodesize *);
60static void sizenodelist(struct nodelist *, struct nodesize *);
61static union node *copynode(union node *, struct nodecopystate *);
62static struct nodelist *copynodelist(struct nodelist *, struct nodecopystate *);
63static char *nodesavestr(const char *, struct nodecopystate *);
64
65
66struct funcdef {
67 unsigned int refcount;
68 union node n;
69};
70
71/*
72 * Make a copy of a parse tree.
73 */
74
75struct funcdef *
76copyfunc(union node *n)
77{
78 struct nodesize sz;
79 struct nodecopystate st;
80 struct funcdef *fn;
81
82 if (n == NULL)
83 return NULL;
84 sz.blocksize = offsetof(struct funcdef, n);
85 sz.stringsize = 0;
86 calcsize(n, &sz);
87 fn = ckmalloc(sz.blocksize + sz.stringsize);
88 fn->refcount = 1;
89 st.block = (char *)fn + offsetof(struct funcdef, n);
90 st.string = (char *)fn + sz.blocksize;
91 copynode(n, &st);
92 return fn;
93}
94
95
96union node *
97getfuncnode(struct funcdef *fn)
98{
99 return fn == NULL ? NULL : &fn->n;
100}
101
102
103static void
104calcsize(union node *n, struct nodesize *result)
105{
106 %CALCSIZE
107}
108
109
110
111static void
112sizenodelist(struct nodelist *lp, struct nodesize *result)
113{
114 while (lp) {
115 result->blocksize += ALIGN(sizeof(struct nodelist));
116 calcsize(lp->n, result);
117 lp = lp->next;
118 }
119}
120
121
122
123static union node *
124copynode(union node *n, struct nodecopystate *state)
125{
126 union node *new;
127
128 %COPY
129 return new;
130}
131
132
133static struct nodelist *
134copynodelist(struct nodelist *lp, struct nodecopystate *state)
135{
136 struct nodelist *start;
137 struct nodelist **lpp;
138
139 lpp = &start;
140 while (lp) {
141 *lpp = state->block;
142 state->block = (char *)state->block +
143 ALIGN(sizeof(struct nodelist));
144 (*lpp)->n = copynode(lp->n, state);
145 lp = lp->next;
146 lpp = &(*lpp)->next;
147 }
148 *lpp = NULL;
149 return start;
150}
151
152
153
154static char *
155nodesavestr(const char *s, struct nodecopystate *state)
156{
157 const char *p = s;
158 char *q = state->string;
159 char *rtn = state->string;
160
161 while ((*q++ = *p++) != '\0')
162 continue;
163 state->string = q;
164 return rtn;
165}
166
167
168void
169reffunc(struct funcdef *fn)
170{
171 if (fn)
172 fn->refcount++;
173}
174
175
176/*
177 * Decrement the reference count of a function definition, freeing it
178 * if it falls to 0.
179 */
180
181void
182unreffunc(struct funcdef *fn)
183{
184 if (fn) {
185 fn->refcount--;
186 if (fn->refcount > 0)
187 return;
188 ckfree(fn);
189 }
190}
