xref: /freebsd/bin/sh/nodes.c.pat (revision 2710751bc309af25c6dea1171781678258e83840) 
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 * 4. 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 *	@(#)nodes.c.pat	8.2 (Berkeley) 5/4/95
33 * $FreeBSD$
34 */
35
36#include <sys/param.h>
37#include <stdlib.h>
38#include <stddef.h>
39/*
40 * Routine for dealing with parsed shell commands.
41 */
42
43#include "shell.h"
44#include "nodes.h"
45#include "memalloc.h"
46#include "mystring.h"
47
48
49static int     funcblocksize;	/* size of structures in function */
50static int     funcstringsize;	/* size of strings in node */
51static pointer funcblock;	/* block to allocate function from */
52static char   *funcstring;	/* block to allocate strings from */
53
54%SIZES
55
56
57static void calcsize(union node *);
58static void sizenodelist(struct nodelist *);
59static union node *copynode(union node *);
60static struct nodelist *copynodelist(struct nodelist *);
61static char *nodesavestr(const char *);
62
63
64struct funcdef {
65	unsigned int refcount;
66	union node n;
67};
68
69/*
70 * Make a copy of a parse tree.
71 */
72
73struct funcdef *
74copyfunc(union node *n)
75{
76	struct funcdef *fn;
77
78	if (n == NULL)
79		return NULL;
80	funcblocksize = offsetof(struct funcdef, n);
81	funcstringsize = 0;
82	calcsize(n);
83	fn = ckmalloc(funcblocksize + funcstringsize);
84	fn->refcount = 1;
85	funcblock = (char *)fn + offsetof(struct funcdef, n);
86	funcstring = (char *)fn + funcblocksize;
87	copynode(n);
88	return fn;
89}
90
91
92union node *
93getfuncnode(struct funcdef *fn)
94{
95	return fn == NULL ? NULL : &fn->n;
96}
97
98
99static void
100calcsize(union node *n)
101{
102	%CALCSIZE
103}
104
105
106
107static void
108sizenodelist(struct nodelist *lp)
109{
110	while (lp) {
111		funcblocksize += ALIGN(sizeof(struct nodelist));
112		calcsize(lp->n);
113		lp = lp->next;
114	}
115}
116
117
118
119static union node *
120copynode(union node *n)
121{
122	union node *new;
123
124	%COPY
125	return new;
126}
127
128
129static struct nodelist *
130copynodelist(struct nodelist *lp)
131{
132	struct nodelist *start;
133	struct nodelist **lpp;
134
135	lpp = &start;
136	while (lp) {
137		*lpp = funcblock;
138		funcblock = (char *)funcblock + ALIGN(sizeof(struct nodelist));
139		(*lpp)->n = copynode(lp->n);
140		lp = lp->next;
141		lpp = &(*lpp)->next;
142	}
143	*lpp = NULL;
144	return start;
145}
146
147
148
149static char *
150nodesavestr(const char *s)
151{
152	const char *p = s;
153	char *q = funcstring;
154	char   *rtn = funcstring;
155
156	while ((*q++ = *p++) != '\0')
157		continue;
158	funcstring = q;
159	return rtn;
160}
161
162
163void
164reffunc(struct funcdef *fn)
165{
166	if (fn)
167		fn->refcount++;
168}
169
170
171/*
172 * Decrement the reference count of a function definition, freeing it
173 * if it falls to 0.
174 */
175
176void
177unreffunc(struct funcdef *fn)
178{
179	if (fn) {
180		fn->refcount--;
181		if (fn->refcount > 0)
182			return;
183		ckfree(fn);
184	}
185}
186