view lwar/add.c @ 273:1409debcb1a0

Fix crash on listing when nested noexpand macros are used Macros flagged noexpand were causing a segfault during listing. The problem was incorrect accounting for nesting levels for noexpand macros causing the listing handler to fall off the end of the program in certain circumstances and in other circumstances it would fail to suppress expansion. Both the segfault in the case of misbehaviour and the misbhaviour itself are corrected with this update. If you do not use nested noexpand macros, this bug has no effect.
author William Astle <lost@l-w.ca>
date Sat, 25 May 2013 13:35:46 -0600
parents 6f4c4d59666f
children 45df37e81741
line wrap: on
line source

/*
add.c
Copyright © 2009 William Astle

This file is part of LWAR.

LWAR is free software: you can redistribute it and/or modify it under the
terms of the GNU General Public License as published by the Free Software
Foundation, either version 3 of the License, or (at your option) any later
version.

This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
more details.

You should have received a copy of the GNU General Public License along with
this program. If not, see <http://www.gnu.org/licenses/>.


Implements the program startup code

*/

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "lwar.h"

void do_add(void)
{
	FILE *f;
	unsigned char buf[8];
	long l;
	int c;
	FILE *f2;
	int i;
	
	f = fopen(archive_file, "rb+");
	if (!f)
	{
		if (errno == ENOENT)
		{
			f = fopen(archive_file, "wb");
			if (f)
			{
				fputs("LWAR1V", f);
				goto doadd;
			}
		}
		perror("Cannot open archive file");
	}
	
	(void)(fread(buf, 1, 6, f) && 1);
	if (memcmp("LWAR1V", buf, 6))
	{
		fprintf(stderr, "%s is not a valid archive file.\n", archive_file);
		exit(1);
	}

	for (;;)
	{
		c = fgetc(f);
		if (c == EOF && ferror(f))
		{
			perror("Reading archive file");
			exit(1);
		}
		if (c == EOF)
			goto doadd;
		
		if (!c)
		{
			fseek(f, -1, SEEK_CUR);
			goto doadd;
		}
		
		// find the end of the file name
		while (c)
		{
			c = fgetc(f);
			if (c == EOF || ferror(f))
			{
				fprintf(stderr, "Bad archive file\n");
				exit(1);
			}
		}
		
		// get length of archive member
		l = 0;
		c = fgetc(f);
		l = c << 24;
		c = fgetc(f);
		l |= c << 16;
		c = fgetc(f);
		l |= c << 8;
		c = fgetc(f);
		l |= c;
		
		fseek(f, l, SEEK_CUR);
	}
	// back up to the NUL byte at the end of the file
	fseek(f, -1, SEEK_CUR);
doadd:
	for (i = 0; i < nfiles; i++)
	{
		f2 = fopen(files[i], "rb");
		if (!f2)
		{
			fprintf(stderr, "Cannot open file %s:", files[i]);
			perror("");
			exit(1);
		}
		(void)(fread(buf, 1, 6, f2) && 1);
		if (mergeflag && !memcmp("LWAR1V", buf, 6))
		{
			// add archive contents...
			for (;;)
			{
				c = fgetc(f2);
				if (c == EOF || ferror(f2))
				{
					perror("Reading input archive file");
					exit(1);
				}
				if (c == EOF)
					break;
		
				if (!c)
				{
					break;
				}
		
				// find the end of the file name
				while (c)
				{
					fputc(c, f);
					c = fgetc(f2);
					if (c == EOF || ferror(f))
					{
						fprintf(stderr, "Bad input archive file\n");
						exit(1);
					}
				}
				fputc(0, f);
				
				// get length of archive member
				l = 0;
				c = fgetc(f2);
				fputc(c, f);
				l = c << 24;
				c = fgetc(f2);
				fputc(c, f);
				l |= c << 16;
				c = fgetc(f2);
				fputc(c, f);
				l |= c << 8;
				c = fgetc(f2);
				fputc(c, f);
				l |= c;
		
				while (l)
				{
					c = fgetc(f2);
					fputc(c, f);
					l--;
				}
			}
			
			fclose(f2);
			continue;
		}
		fseek(f2, 0, SEEK_END);
		l = ftell(f2);
		fseek(f2, 0, SEEK_SET);
		fputs(files[i], f);
		fputc(0, f);
		fputc(l >> 24, f);
		fputc((l >> 16) & 0xff, f);
		fputc((l >> 8) & 0xff, f);
		fputc(l & 0xff, f);
		while (l)
		{
			c = fgetc(f2);
			fputc(c, f);
			l--;
		}
	}
	
	// flag end of file
	fputc(0, f);	
}