/* $OpenBSD: buf.c,v 1.31 2024/06/18 02:11:03 millert 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 "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(void) { 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; }
