view loadtools/ltdispatch.c @ 465:003e48f8ebe1

rvinterf/etmsync/fsnew.c: cast 0 to (char *) for execl sentinel I generally don't use NULL and use plain 0 instead, based on a "NULL considered harmful" discussion on the classiccmp mailing list many aeons ago (I couldn't find it, and I reason that it must have been 2005 or earlier), but a recent complaint by a packager sent me searching, and I found this: https://ewontfix.com/11/ While I don't give a @#$% about "modern" systems and code-nazi tools, I realized that passing a plain 0 as a pointer sentinel in execl is wrong because it will break on systems where pointers are longer than the plain int type. Again, I don't give a @#$% about the abomination of x86_64 and the like, but if anyone ever manages to port my code to something like a PDP-11 (16-bit int, 32-bit long and pointers), then passing a plain 0 as a function argument where a pointer is expected most definitely won't work: if the most natural stack slot and SP alignment unit is 16 bits, fitting an int, with longs and pointers taking up two such slots, then the call stack will be totally wrong with a plain 0 passed for a pointer. Casting the 0 to (char *) ought to be the most kosher solution for the most retro systems possible.
author Mychaela Falconia <falcon@freecalypso.org>
date Mon, 11 Feb 2019 00:00:19 +0000
parents e7502631a0f9
children 0d199c6a6ea4
line wrap: on
line source

/*
 * This module implements the command dispatch for fc-loadtool
 */

#include <ctype.h>
#include <stdio.h>
#include <string.h>
#include <strings.h>
#include <stdlib.h>

extern int cmd_baud();
extern int cmd_crc32();
extern int cmd_dieid();
extern int cmd_dump2bin();
extern int cmd_dump2srec();
extern int cmd_exec();
extern int cmd_exit();
extern int cmd_flash();
extern int cmd_help();
extern int loadtool_cmd_passthru();

static struct cmdtab {
	char *cmd;
	int minargs;
	int maxargs;
	int (*func)();
} cmdtab[] = {
	{"abbr", 2, 2, loadtool_cmd_passthru},
	{"abbw", 3, 3, loadtool_cmd_passthru},
	{"baud", 0, 1, cmd_baud},
	{"crc32", 2, 2, cmd_crc32},
	{"dieid", 0, 1, cmd_dieid},
	{"dump", 2, 2, loadtool_cmd_passthru},
	{"dump2bin", 3, 3, cmd_dump2bin},
	{"dump2srec", 3, 3, cmd_dump2srec},
	{"exec", 1, 1, cmd_exec},
	{"exit", 0, 1, cmd_exit},
	{"flash", 1, 5, cmd_flash},
	{"flash2", 1, 5, cmd_flash},
	{"help", 0, 2, cmd_help},
	{"quit", 0, 1, cmd_exit},
	{"r8", 1, 1, loadtool_cmd_passthru},
	{"r16", 1, 1, loadtool_cmd_passthru},
	{"r32", 1, 1, loadtool_cmd_passthru},
	{"w8", 2, 2, loadtool_cmd_passthru},
	{"w16", 2, 2, loadtool_cmd_passthru},
	{"w32", 2, 2, loadtool_cmd_passthru},
	{0, 0, 0, 0}
};

loadtool_dispatch_cmd(cmd, is_script)
	char *cmd;
{
	char *argv[10];
	char *cp, **ap;
	struct cmdtab *tp;

	for (cp = cmd; isspace(*cp); cp++)
		;
	if (!*cp || *cp == '#')
		return(0);
	if (is_script)
		printf("Script command: %s\n", cp);
	argv[0] = cp;
	while (*cp && !isspace(*cp))
		cp++;
	if (*cp)
		*cp++ = '\0';
	for (tp = cmdtab; tp->cmd; tp++)
		if (!strcmp(tp->cmd, argv[0]))
			break;
	if (!tp->func) {
		fprintf(stderr, "error: no such command\n");
		return(-1);
	}
	for (ap = argv + 1; ; ) {
		while (isspace(*cp))
			cp++;
		if (!*cp || *cp == '#')
			break;
		if (ap - argv - 1 >= tp->maxargs) {
			fprintf(stderr, "error: too many arguments\n");
			return(-1);
		}
		*ap++ = cp;
		while (*cp && !isspace(*cp))
			cp++;
		if (*cp)
			*cp++ = '\0';
	}
	if (ap - argv - 1 < tp->minargs) {
		fprintf(stderr, "error: too few arguments\n");
		return(-1);
	}
	*ap = 0;
	return tp->func(ap - argv, argv);
}