File: [local] / src / usr.bin / make / buf.c (download)
Revision 1.29, Mon Jan 13 13:54:44 2020 UTC (4 years, 5 months ago) by espie
Branch: MAIN
CVS Tags: OPENBSD_7_3_BASE, OPENBSD_7_3, OPENBSD_7_2_BASE, OPENBSD_7_2, OPENBSD_7_1_BASE, OPENBSD_7_1, OPENBSD_7_0_BASE, OPENBSD_7_0, OPENBSD_6_9_BASE, OPENBSD_6_9, OPENBSD_6_8_BASE, OPENBSD_6_8, OPENBSD_6_7_BASE, OPENBSD_6_7 Changes since 1.28: +10 -1 lines
introduce a "Buf_Reinit" function for handling static buffers that can
be reused throughout running make. Instead of recreating buffers of
dubious appropriate size, have one single buffer for various stages of
parsing.
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/* $OpenBSD: buf.c,v 1.29 2020/01/13 13:54:44 espie Exp $ */
/* $NetBSD: buf.c,v 1.9 1996/12/31 17:53:21 christos Exp $ */
/*
* Copyright (c) 1999 Marc Espie.
*
* Extensive code changes for the OpenBSD project.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OPENBSD
* PROJECT OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* Copyright (c) 1988, 1989, 1990 The Regents of the University of California.
* Copyright (c) 1988, 1989 by Adam de Boor
* Copyright (c) 1989 by Berkeley Softworks
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Adam de Boor.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
/*-
* buf.c --
* Functions for automatically expanded buffers.
*/
#include <assert.h>
#include <ctype.h>
#include <limits.h>
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <stdarg.h>
#include "config.h"
#include "defines.h"
#include "buf.h"
#include "stats.h"
#include "memory.h"
#ifdef STATS_BUF
#define DO_STAT_BUF(bp, nb) \
STAT_BUFS_EXPANSION++; \
if ((bp)->endPtr - (bp)->buffer == 1) \
STAT_WEIRD_INEFFICIENT++;
#else
#define DO_STAT_BUF(a, b)
#endif
static void
fatal_overflow()
{
fprintf(stderr, "buffer size overflow\n");
exit(2);
}
#define BUF_DEF_SIZE 256U /* Default buffer size */
#define BUF_MARGIN 256U /* Make sure we are comfortable */
/* BufExpand(bp, nb)
* Expand buffer bp to hold up to nb additional
* chars. Makes sure there's always room for an extra '\0' char
* at the end of the buffer for Buf_Retrieve. */
void
BufExpand(Buffer bp, size_t nb)
{
size_t occupied = bp->inPtr - bp->buffer;
size_t size = bp->endPtr - bp->buffer;
DO_STAT_BUF(bp, nb);
do {
if (size <= SIZE_MAX/2) {
size *= 2 ;
} else {
fatal_overflow();
}
assert(size >= occupied);
} while (size - occupied < nb+1+BUF_MARGIN);
bp->buffer = erealloc(bp->buffer, size);
bp->inPtr = bp->buffer +occupied;
bp->endPtr = bp->buffer + size;
}
void
Buf_AddChars(Buffer bp, size_t numBytes, const char *bytesPtr)
{
assert(bp->endPtr >= bp->inPtr);
if ((size_t)(bp->endPtr - bp->inPtr) < numBytes+1)
BufExpand(bp, numBytes);
memcpy(bp->inPtr, bytesPtr, numBytes);
bp->inPtr += numBytes;
}
void
Buf_printf(Buffer bp, const char *fmt, ...)
{
va_list va;
int n;
va_start(va, fmt);
n = vsnprintf(bp->inPtr, bp->endPtr - bp->inPtr, fmt, va);
va_end(va);
if (n+1 > bp->endPtr - bp->inPtr) {
va_list vb;
BufExpand(bp, n);
va_start(vb, fmt);
(void)vsnprintf(bp->inPtr, bp->endPtr - bp->inPtr, fmt, vb);
va_end(vb);
}
bp->inPtr += n;
}
void
Buf_Reinit(Buffer bp, size_t size)
{
if (bp->buffer == NULL)
Buf_Init(bp, size);
else
Buf_Reset(bp);
}
void
Buf_Init(Buffer bp, size_t size)
{
#ifdef STATS_BUF
STAT_TOTAL_BUFS++;
if (size == 0)
STAT_DEFAULT_BUFS++;
if (size == 1)
STAT_WEIRD_BUFS++;
#endif
if (size == 0)
size = BUF_DEF_SIZE;
bp->inPtr = bp->endPtr = bp->buffer = emalloc(size);
bp->endPtr += size;
}