view output.c @ 203:3a25180d3a5c

Abort on line numbering or column numbering overflow. Line numbers are limited to values that fit in "unsigned int". Also reject input lines longer than 2^32-1 characters. It seems reasonable to presume that any input that violates these constraints is someone screwing around and not a serious attempt to compile or preprocess anything useful. Done in response to n2129, but without getting into any of the silliness found there.
author David A. Holland
date Tue, 01 Aug 2017 14:51:04 -0400
parents 16b4451e34b8
children
line wrap: on
line source

/*-
 * Copyright (c) 2010 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * This code is derived from software contributed to The NetBSD Foundation
 * by David A. Holland.
 *
 * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
 */

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>

#include "utils.h"
#include "mode.h"
#include "place.h"
#include "output.h"

static int outputfd = -1;
static bool incomment = false;
static char *linebuf;
static size_t linebufpos, linebufmax;
static struct place linebufplace;

static
void
output_open(void)
{
	if (mode.output_file == NULL) {
		outputfd = STDOUT_FILENO;
	} else {
		outputfd = open(mode.output_file, O_WRONLY|O_CREAT|O_TRUNC,
				0664);
		if (outputfd < 0) {
			complain(NULL, "%s: %s",
				 mode.output_file, strerror(errno));
			die();
		}
	}
}

static
void
dowrite(const char *buf, size_t len)
{
	size_t done;
	ssize_t result;
	static unsigned write_errors = 0;

	if (!mode.do_output) {
		return;
	}

	if (outputfd < 0) {
		output_open();
	}

	done = 0;
	while (done < len) {
		result = write(outputfd, buf+done, len-done);
		if (result == -1) {
			complain(NULL, "%s: write: %s",
				 mode.output_file, strerror(errno));
			complain_failed();
			write_errors++;
			if (write_errors > 5) {
				complain(NULL, "%s: giving up",
					 mode.output_file);
				die();
			}
			/* XXX is this really a good idea? */
			sleep(1);
		}
		done += (size_t)result;
	}
}


static
void
filter_output(const char *buf, size_t len)
{
	size_t pos, start;
	bool inesc = false;
	bool inquote = false;
	char quote = '\0';

	start = 0;
	for (pos = 0; pos < len - 1; pos++) {
		if (!inquote && buf[pos] == '/' && buf[pos+1] == '*') {
			if (!incomment) {
				if (pos > start) {
					dowrite(buf + start, pos - start);
				}
				start = pos;
				pos += 2;
				incomment = true;
				/* cancel out the loop's pos++ */
				pos--;
				continue;
			}
		} else if (buf[pos] == '*' && buf[pos+1] == '/') {
			if (incomment) {
				pos += 2;
				if (mode.output_retain_comments) {
					dowrite(buf + start, pos - start);
				}
				start = pos;
				incomment = false;
				/* cancel out the loop's pos++ */
				pos--;
				continue;
			}
		}

		if (incomment) {
			/* nothing */
		} else if (inesc) {
			inesc = false;
		} else if (buf[pos] == '\\') {
			inesc = true;
		} else if (!inquote && (buf[pos] == '"' || buf[pos] == '\'')) {
			inquote = true;
			quote = buf[pos];
		} else if (inquote && buf[pos] == quote) {
			inquote = false;
		}
	}
	pos++;

	if (pos > start) {
		if (!incomment || mode.output_retain_comments) {
			dowrite(buf + start, pos - start);
		}
	}
}

void
output(const struct place *p, const char *buf, size_t len)
{
	size_t oldmax;

	if (linebufpos + len > linebufmax) {
		oldmax = linebufmax;
		if (linebufmax == 0) {
			linebufmax = 64;
		}
		while (linebufpos + len > linebufmax) {
			linebufmax *= 2;
		}
		linebuf = dorealloc(linebuf, oldmax, linebufmax);
	}
	if (linebufpos == 0) {
		if (!place_samefile(&linebufplace, p)) {
			if (mode.output_cheaplinenumbers) {
				char str[256];

				snprintf(str, sizeof(str), "# %u \"%s\"\n",
					 p->line, place_getname(p));
				dowrite(str, strlen(str));
			}
		}
		linebufplace = *p;
	}
	memcpy(linebuf + linebufpos, buf, len);
	linebufpos += len;

	if (len == 1 && buf[0] == '\n') {
		filter_output(linebuf, linebufpos);
		linebufpos = 0;
	}
}

void
output_eof(void)
{
	if (mode.output_file != NULL && outputfd >= 0) {
		close(outputfd);
	}
	outputfd = -1;
}