AUSAM/source/make/dosys.c

# include "defs"

dosys(comstring, nohalt)
char *comstring;
int nohalt;
{
	int status;


	if(metas(comstring))
		status = doshell(comstring, nohalt);
	else
		status = doexec(comstring);

	return(status>>8);
}



metas(s) /* Are there are any  Shell meta-characters? */ 
char *s;
{
	for(; ; )
		switch(*s++)
		{
		case '|':
		case '^':
		case '(':
		case ')':
		case ';':
		case '&':
		case '<':
		case '>':
		case '*':
		case '?':
		case '[':
		case ']':
		case '\\':
		case '\n':
		case '\'':
		case '"':
		case '`':
		case '$':
		case ':':
			return(1);

		case '\0':
			return(0);
		};
}

doshell(comstring, nohalt)
char *comstring;
int nohalt;
{
	if(fork() == 0)
	{
		enbint(0);
		doclose();

		if(execl(SHELLCOM, "sh", "-c", comstring, 0))
			fatal("Couldn't load Shell");
	}

	return(await());
}




await()
{
	int intrupt();
	int status;


	disint();
	waitx(&status);
	enbint(intrupt);
	return(status);
}






doclose() /* Close open directory files before exec'ing */ 
{
	register struct opendir *od;

	for(od = firstod; od != 0; od = od->nextp)
		if(od->dirfc != NULL)
			fclose(od->dirfc);
}





doexec(str)
char *str;
{
	register char *s, *t;
	char *argv[100], pool[1000];
	int status;
	int argc;



	argc = 0;
	s = pool;

	for(t = str; *t != '\0'; )
	{
		while(*t == ' ' || *t == '\t')
			++t;
		if(*t == '\0')
			break;

		argv[argc++] = s;
		while(*t != ' ' && *t != '\t' && *t != '\0')
			*s++ = *t++;
		*s++ = '\0';
	}

	if(argc == 0)	/* no command */ 
		return(-1);
	argv[argc] = 0;

	if(fork() == 0)
	{
		enbint(0);
		doclose();

		execc(argv[0], argv);
		fprintf(stderr, "*** Cannot load %s", argv[0]);
		fatal("");
	}

	return(await());
}


char junkname[16];

touch(s)
char *s;
{
	if(junkname[0] == 0)
		sprintf(junkname, "MAKEJUNK%d", getpid());

	link(s, junkname);
	unlink(junkname);
}