xref: /openbsd-src/usr.bin/make/buf.c (revision b2ea75c1b17e1a9a339660e7ed45cd24946b230e)
1 /*	$OpenPackages$ */
2 /*	$OpenBSD: buf.c,v 1.18 2001/05/30 00:43:00 deraadt Exp $	*/
3 /*	$NetBSD: buf.c,v 1.9 1996/12/31 17:53:21 christos Exp $ */
4 
5 /*
6  * Copyright (c) 1999 Marc Espie.
7  *
8  * Extensive code changes for the OpenBSD project.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22  * A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OPENBSD
23  * PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30  */
31 /*
32  * Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
33  * Copyright (c) 1988, 1989 by Adam de Boor
34  * Copyright (c) 1989 by Berkeley Softworks
35  * All rights reserved.
36  *
37  * This code is derived from software contributed to Berkeley by
38  * Adam de Boor.
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in the
47  *    documentation and/or other materials provided with the distribution.
48  * 3. All advertising materials mentioning features or use of this software
49  *    must display the following acknowledgement:
50  *	This product includes software developed by the University of
51  *	California, Berkeley and its contributors.
52  * 4. Neither the name of the University nor the names of its contributors
53  *    may be used to endorse or promote products derived from this software
54  *    without specific prior written permission.
55  *
56  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
57  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
58  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
59  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
60  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
61  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
62  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
63  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
64  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
65  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
66  * SUCH DAMAGE.
67  */
68 
69 /*-
70  * buf.c --
71  *	Functions for automatically-expanded buffers.
72  */
73 
74 #include <ctype.h>
75 #include <stddef.h>
76 #include <string.h>
77 #include "config.h"
78 #include "defines.h"
79 #include "buf.h"
80 #include "stats.h"
81 #include "memory.h"
82 
83 #ifdef STATS_BUF
84 #define DO_STAT_BUF(bp, nb)					\
85 	STAT_BUFS_EXPANSION++;			\
86 	if ((bp)->endPtr - (bp)->buffer == 1)			\
87 		STAT_WEIRD_INEFFICIENT++;
88 #else
89 #define DO_STAT_BUF(a, b)
90 #endif
91 
92 /* BufExpand(bp, nb)
93  *	Expand buffer bp to hold upto nb additional
94  *	chars.	Makes sure there's room for an extra '\0' char at
95  *	the end of the buffer to terminate the string.	*/
96 #define BufExpand(bp,nb)				\
97 do {							\
98     size_t   occupied = (bp)->inPtr - (bp)->buffer;	\
99     size_t   size = (bp)->endPtr - (bp)->buffer;	\
100     DO_STAT_BUF(bp, nb);				\
101 							\
102     do {						\
103 	size *= 2 ;					\
104     } while (size - occupied < (nb)+1+BUF_MARGIN);	\
105     (bp)->buffer = (bp)->inPtr = (bp)->endPtr = 	\
106 	erealloc((bp)->buffer, size);			\
107     (bp)->inPtr += occupied;				\
108     (bp)->endPtr += size;				\
109 } while (0);
110 
111 #define BUF_DEF_SIZE	256	/* Default buffer size */
112 #define BUF_MARGIN	256	/* Make sure we are comfortable */
113 
114 /* the hard case for Buf_AddChar: buffer must be expanded to accommodate
115  * one more char.  */
116 void
117 BufOverflow(bp)
118     Buffer bp;
119 {
120     BufExpand(bp, 1);
121 }
122 
123 
124 void
125 Buf_AddChars(bp, numBytes, bytesPtr)
126     Buffer	bp;
127     size_t	numBytes;
128     const char	*bytesPtr;
129 {
130 
131     if ((size_t)(bp->endPtr - bp->inPtr) < numBytes+1)
132 	BufExpand(bp, numBytes);
133 
134     memcpy(bp->inPtr, bytesPtr, numBytes);
135     bp->inPtr += numBytes;
136 }
137 
138 
139 void
140 Buf_Init(bp, size)
141     Buffer bp;
142     size_t    size;
143 {
144 #ifdef STATS_BUF
145     STAT_TOTAL_BUFS++;
146     if (size == 0)
147 	STAT_DEFAULT_BUFS++;
148     if (size == 1)
149 	STAT_WEIRD_BUFS++;
150 #endif
151     if (size == 0)
152 	size = BUF_DEF_SIZE;
153     bp->inPtr = bp->endPtr = bp->buffer = emalloc(size);
154     bp->endPtr += size;
155 }
156 
157 void
158 Buf_KillTrailingSpaces(bp)
159     Buffer bp;
160 {
161     while (bp->inPtr > bp->buffer + 1 && isspace(bp->inPtr[-1])) {
162 	if (bp->inPtr[-2] == '\\')
163 	    break;
164 	bp->inPtr--;
165     }
166 }
167