view lwlink/map.c @ 530:65c2085e0398

Don't rely on undefined memory before start of instab When encountering a symbol on a line by itself, cl->insn was used to index into the instab array. Unfortunately, in that case, cl->insn will be -1 which will refer to memory before the start of instab. Depending on the compiler and linker, that could be anything. This would only have a visible effect on the OS9 target which has separate data and code address counters. On other targets, the two counters are kept in sync. This patch should short circuit that unfortunate code issue.
author William Astle <lost@l-w.ca>
date Wed, 09 Mar 2022 15:56:03 -0700
parents d389adbcc4ab
children
line wrap: on
line source

/*
map.c
Copyright © 2009 William Astle

This file is part of LWLINK.

LWLINK 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/>.


Output information about the linking process
*/

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

#include <lw_alloc.h>

#include "lwlink.h"

struct symliste
{
	char *name;
	char *fn;
	int addr;
	int ext;
	struct symliste *next;
};

void display_map(void)
{
	FILE *of;
	int sn;
	int std = 0;
	struct symliste *slist = NULL;
	struct symliste *ce, *pe, *ne;
	symtab_t *sym;
	int i;
	symlist_t *se;
	
	if (!strcmp(map_file, "-"))
	{
		std = 1;
		of = stdout;
	}
	else
	{
		of = fopen(map_file, "w");
		if (!of)
		{
			fprintf(stderr, "Cannot open map file - using stdout\n");
			std = 1;
			of = stdout;
		}
	}

	// display section list
	for (sn = 0; sn < nsects; sn++)
	{
		fprintf(of, "Section: %s (%s) load at %04X, length %04X\n",
				sanitize_symbol((char*)(sectlist[sn].ptr -> name)),
				sectlist[sn].ptr -> file -> filename,
				sectlist[sn].ptr -> loadaddress,
				sectlist[sn].ptr -> codesize
			);
	}

	// generate a sorted list of symbols and display it
	
	for (se = symlist; se; se = se -> next)
	{
		for (pe = NULL, ce = slist; ce; ce = ce -> next)
		{
			i = strcmp(ce -> name, se -> sym);
			if (i > 0)
			{
				break;
			}
			pe = ce;
		}
		
		ne = lw_alloc(sizeof(struct symliste));
		ne -> ext = 1;
		ne -> addr = se -> val;
		ne -> next = ce;
		ne -> name = se -> sym;
		ne -> fn = "<synthetic>";
		if (pe)
			pe -> next = ne;
		else
			slist = ne;
	}
	
	for (sn = 0; sn < nsects; sn++)
	{
		for (sym = sectlist[sn].ptr -> localsyms; sym; sym = sym -> next)
		{
			for (pe = NULL, ce = slist; ce; ce = ce -> next)
			{
				i = strcmp(ce -> name, (char *)(sym -> sym));
				if (i == 0)
				{
					i = strcmp(ce -> fn, sectlist[sn].ptr -> file -> filename);
				}
				if (i > 0)
					break;
				pe = ce;
			}
			ne = lw_alloc(sizeof(struct symliste));
			ne -> ext = 0;
			if (sectlist[sn].ptr -> flags & SECTION_CONST)
				ne -> addr = sym -> offset;
			else
				ne -> addr = sym -> offset + sectlist[sn].ptr -> loadaddress;
			ne -> next = ce;
			ne -> name = (char *)(sym -> sym);
			ne -> fn = sectlist[sn].ptr -> file -> filename;
			if (pe)
				pe -> next = ne;
			else
				slist = ne;
		}
	}
	
	for (ce = slist; ce; ce = ce -> next)
	{
		fprintf(of, "Symbol: %s (%s) = %04X\n", sanitize_symbol(ce -> name), ce -> fn, ce -> addr);
	}

	if (!std)
		fclose(of);
}