msh.c

shell-HHARM9200.rar 华恒 AT91rm9200 中Busybox shell的源代码

			*v = e.linep;
			execve(DEFAULT_SHELL, v, envp);
			*v = tp;
			return("no Shell");

		case ENOMEM:
			return((char*)bb_msg_memory_exhausted);

		case E2BIG:
			return("argument list too long");

		case EACCES:
			eacces++;
			break;
		}
	}
	return(errno==ENOENT ? "not found" : "cannot execute");
}

/*
 * Run the command produced by generator `f'
 * applied to stream `arg'.
 */
static int
run(struct ioarg *argp, int (*f)(struct ioarg *))
{
	struct op *otree;
	struct wdblock *swdlist;
	struct wdblock *siolist;
	jmp_buf ev, rt;
	xint *ofail;
	int rv;

#if __GNUC__
	/* Avoid longjmp clobbering */
	(void) &rv;
#endif

	areanum++;
	swdlist = wdlist;
	siolist = iolist;
	otree = outtree;
	ofail = failpt;
	rv = -1;
	if (newenv(setjmp(errpt = ev)) == 0) {
		wdlist = 0;
		iolist = 0;
		pushio(argp, f);
		e.iobase = e.iop;
		yynerrs = 0;
		if (setjmp(failpt = rt) == 0 && yyparse() == 0)
			rv = execute(outtree, NOPIPE, NOPIPE, 0);
		quitenv();
	}
	wdlist = swdlist;
	iolist = siolist;
	failpt = ofail;
	outtree = otree;
	freearea(areanum--);
	return(rv);
}

/* -------- do.c -------- */

/*
 * built-in commands: doX
 */

static int dohelp(struct op *t )
{
	int col;
	const struct builtincmd *x;

	printf("\nBuilt-in commands:\n");
	printf("-------------------\n");

	for (col=0, x = builtincmds; x->builtinfunc != NULL; x++) {
		if (!x->name)
			continue;
		col += printf("%s%s", ((col == 0) ? "\t" : " "), x->name);
		if (col > 60) {
			printf("\n");
			col = 0;
		}
	}
#ifdef CONFIG_FEATURE_SH_STANDALONE_SHELL
	{
		int i;
		const struct BB_applet *applet;
		extern const struct BB_applet applets[];
		extern const size_t NUM_APPLETS;

		for (i=0, applet = applets; i < NUM_APPLETS; applet++, i++) {
			if (!applet->name)
				continue;

			col += printf("%s%s", ((col == 0) ? "\t" : " "),
					applet->name);
			if (col > 60) {
				printf("\n");
				col = 0;
			}
		}
	}
#endif
	printf("\n\n");
	return EXIT_SUCCESS;
}



static int dolabel(struct op *t )
{
	return(0);
}

static int
dochdir(t)
register struct op *t;
{
	register char *cp, *er;

	if ((cp = t->words[1]) == NULL && (cp = homedir->value) == NULL)
		er = ": no home directory";
	else if(chdir(cp) < 0)
		er = ": bad directory";
	else
		return(0);
	prs(cp != NULL? cp: "cd");
	err(er);
	return(1);
}

static int
doshift(t)
register struct op *t;
{
	register int n;

	n = t->words[1]? getn(t->words[1]): 1;
	if(dolc < n) {
		err("nothing to shift");
		return(1);
	}
	dolv[n] = dolv[0];
	dolv += n;
	dolc -= n;
	setval(lookup("#"), putn(dolc));
	return(0);
}

/*
 * execute login and newgrp directly
 */
static int
dologin(t)
struct op *t;
{
	register char *cp;

	if (interactive) {
		signal(SIGINT, SIG_DFL);
		signal(SIGQUIT, SIG_DFL);
	}
	cp = rexecve(t->words[0], t->words, makenv());
	prs(t->words[0]); prs(": "); err(cp);
	return(1);
}

static int
doumask(t)
register struct op *t;
{
	register int i, n;
	register char *cp;

	if ((cp = t->words[1]) == NULL) {
		i = umask(0);
		umask(i);
		for (n=3*4; (n-=3) >= 0;)
			putc('0'+((i>>n)&07), stderr);
		putc('\n', stderr);
	} else {
		for (n=0; *cp>='0' && *cp<='9'; cp++)
			n = n*8 + (*cp-'0');
		umask(n);
	}
	return(0);
}

static int
doexec(t)
register struct op *t;
{
	register int i;
	jmp_buf ex;
	xint *ofail;

	t->ioact = NULL;
	for(i = 0; (t->words[i]=t->words[i+1]) != NULL; i++)
		;
	if (i == 0)
		return(1);
	execflg = 1;
	ofail = failpt;
	if (setjmp(failpt = ex) == 0)
		execute(t, NOPIPE, NOPIPE, FEXEC);
	failpt = ofail;
	execflg = 0;
	return(1);
}

static int
dodot(t)
struct op *t;
{
	register int i;
	register char *sp, *tp;
	char *cp;

	if ((cp = t->words[1]) == NULL)
		return(0);
	sp = any('/', cp)? ":": path->value;
	while (*sp) {
		tp = e.linep;
		while (*sp && (*tp = *sp++) != ':')
			tp++;
		if (tp != e.linep)
			*tp++ = '/';
		for (i = 0; (*tp++ = cp[i++]) != '\0';)
			;
		if ((i = open(e.linep, 0)) >= 0) {
			exstat = 0;
			next(remap(i));
			return(exstat);
		}
	}
	prs(cp);
	err(": not found");
	return(-1);
}

static int
dowait(t)
struct op *t;
{
	register int i;
	register char *cp;

	if ((cp = t->words[1]) != NULL) {
		i = getn(cp);
		if (i == 0)
			return(0);
	} else
		i = -1;
	setstatus(waitfor(i, 1));
	return(0);
}

static int
doread(t)
struct op *t;
{
	register char *cp, **wp;
	register int nb = 0;
	register int  nl = 0;

	if (t->words[1] == NULL) {
		err("Usage: read name ...");
		return(1);
	}
	for (wp = t->words+1; *wp; wp++) {
		for (cp = e.linep; !nl && cp < elinep-1; cp++)
			if ((nb = read(0, cp, sizeof(*cp))) != sizeof(*cp) ||
			    (nl = (*cp == '\n')) ||
			    (wp[1] && any(*cp, ifs->value)))
				break;
		*cp = 0;
		if (nb <= 0)
			break;
		setval(lookup(*wp), e.linep);
	}
	return(nb <= 0);
}

static int
doeval(t)
register struct op *t;
{
	return(RUN(awordlist, t->words+1, wdchar));
}

static int
dotrap(t)
register struct op *t;
{
	register int  n, i;
	register int  resetsig;

	if (t->words[1] == NULL) {
		for (i=0; i<=_NSIG; i++)
			if (trap[i]) {
				prn(i);
				prs(": ");
				prs(trap[i]);
				prs("\n");
			}
		return(0);
	}
	resetsig = isdigit(*t->words[1]);
	for (i = resetsig ? 1 : 2; t->words[i] != NULL; ++i) {
		n = getsig(t->words[i]);
		freecell(trap[n]);
		trap[n] = 0;
		if (!resetsig) {
			if (*t->words[1] != '\0') {
				trap[n] = strsave(t->words[1], 0);
				setsig(n, sig);
			} else
				setsig(n, SIG_IGN);
		} else {
			if (interactive)
				if (n == SIGINT)
					setsig(n, onintr);
				else
					setsig(n, n == SIGQUIT ? SIG_IGN
							       : SIG_DFL);
			else
				setsig(n, SIG_DFL);
		}
	}
	return(0);
}

static int
getsig(s)
char *s;
{
	register int n;

	if ((n = getn(s)) < 0 || n > _NSIG) {
		err("trap: bad signal number");
		n = 0;
	}
	return(n);
}

static void
setsig( register int n, sighandler_t f)
{
	if (n == 0)
		return;
	if (signal(n, SIG_IGN) != SIG_IGN || ourtrap[n]) {
		ourtrap[n] = 1;
		signal(n, f);
	}
}

static int
getn(as)
char *as;
{
	register char *s;
	register int n, m;

	s = as;
	m = 1;
	if (*s == '-') {
		m = -1;
		s++;
	}
	for (n = 0; isdigit(*s); s++)
		n = (n*10) + (*s-'0');
	if (*s) {
		prs(as);
		err(": bad number");
	}
	return(n*m);
}

static int
dobreak(t)
struct op *t;
{
	return(brkcontin(t->words[1], 1));
}

static int
docontinue(t)
struct op *t;
{
	return(brkcontin(t->words[1], 0));
}

static int
brkcontin(cp, val)
register char *cp;
int val;
{
	register struct brkcon *bc;
	register int nl;

	nl = cp == NULL? 1: getn(cp);
	if (nl <= 0)
		nl = 999;
	do {
		if ((bc = brklist) == NULL)
			break;
		brklist = bc->nextlev;
	} while (--nl);
	if (nl) {
		err("bad break/continue level");
		return(1);
	}
	isbreak = val;
	longjmp(bc->brkpt, 1);
	/* NOTREACHED */
}

static int
doexit(t)
struct op *t;
{
	register char *cp;

	execflg = 0;
	if ((cp = t->words[1]) != NULL)
		setstatus(getn(cp));
	leave();
	/* NOTREACHED */
	return(0);
}

static int
doexport(t)
struct op *t;
{
	rdexp(t->words+1, export, EXPORT);
	return(0);
}

static int
doreadonly(t)
struct op *t;
{
	rdexp(t->words+1, ronly, RONLY);
	return(0);
}

static void rdexp (char **wp, void (*f)(struct var *), int key)
{
	if (*wp != NULL) {
		for (; *wp != NULL; wp++) {
			if (isassign(*wp)) {
				char *cp;
				assign(*wp, COPYV);
				for (cp = *wp; *cp != '='; cp++)
					;
				*cp = '\0';
			}
			if (checkname(*wp))
				(*f)(lookup(*wp));
			else
				badid(*wp);
		}
	} else
		putvlist(key, 1);
}

static void
badid(s)
register char *s;
{
	prs(s);
	err(": bad identifier");
}

static int
doset(t)
register struct op *t;
{
	register struct var *vp;
	register char *cp;
	register int n;

	if ((cp = t->words[1]) == NULL) {
		for (vp = vlist; vp; vp = vp->next)
			varput(vp->name, 1);
		return(0);
	}
	if (*cp == '-') {
		/* bad: t->words++; */
		for(n = 0; (t->words[n]=t->words[n+1]) != NULL; n++)
			;
		if (*++cp == 0)
			flag['x'] = flag['v'] = 0;
		else
			for (; *cp; cp++)
				switch (*cp) {
				case 'e':
					if (!interactive)
						flag['e']++;
					break;

				default:
					if (*cp>='a' && *cp<='z')
						flag[(int)*cp]++;
					break;
				}
		setdash();
	}
	if (t->words[1]) {
		t->words[0] = dolv[0];
		for (n=1; t->words[n]; n++)
			setarea((char *)t->words[n], 0);
		dolc = n-1;
		dolv = t->words;
		setval(lookup("#"), putn(dolc));
		setarea((char *)(dolv-1), 0);
	}
	return(0);
}

static void
varput(s, out)
register char *s;
int out;
{
	if (isalnum(*s) || *s == '_') {
		write(out, s, strlen(s));
		write(out, "\n", 1);
	}
}


/*
 * Copyright (c) 1999 Herbert Xu <[e-mail]>
 * This file contains code for the times builtin.
 */
static int dotimes(struct op *t )
{
	struct tms buf;
	long int clk_tck = sysconf(_SC_CLK_TCK);

	times(&buf);
	printf("%dm%fs %dm%fs\n%dm%fs %dm%fs\n",
	       (int) (buf.tms_utime / clk_tck / 60),
	       ((double) buf.tms_utime) / clk_tck,
	       (int) (buf.tms_stime / clk_tck / 60),
	       ((double) buf.tms_stime) / clk_tck,
	       (int) (buf.tms_cutime / clk_tck / 60),
	       ((double) buf.tms_cutime) / clk_tck,
	       (int) (buf.tms_cstime / clk_tck / 60),
	       ((double) buf.tms_cstime) / clk_tck);
	return 0;
}


static int(*inbuilt(char *s))(struct op *)
{
	const struct builtincmd *bp;

	for (bp = builtincmds; bp->name != NULL; bp++)
		if (strcmp(bp->name, s) == 0)
			return(bp->builtinfunc);

	return(NULL);
}

/* -------- eval.c -------- */

/*
 * ${}
 * `command`
 * blank interpretation
 * quoting
 * glob
 */

static char ** eval( char **ap, int f)
{
	struct wdblock *wb;
	char **wp;
	char **wf;
	jmp_buf ev;

#if __GNUC__
	/* Avoid longjmp clobbering */
	(void) &wp;
	(void) &ap;
#endif
	wp = NULL;
	wb = NULL;
	wf = NULL;
	if (newenv(setjmp(errpt = ev)) == 0) {
		while (*ap && isassign(*ap))
			expand(*ap++, &wb, f & ~DOGLOB);
		if (flag['k']) {
			for (wf = ap; *wf; wf++) {
				if (isassign(*wf))
					expand(*wf, &wb, f & ~DOGLOB);
			}
		}
		for (wb = addword((char *)0, wb); *ap; ap++) {
			if (!flag['k'] || !isassign(*ap))
				expand(*ap, &wb, f & ~DOKEY);
		}
		wb = addword((char *)0, wb);
		wp = getwords(wb);
		quitenv();
	} else
		gflg = 1;
	return(gflg? (char **)NULL: wp);
}

/*
 * Make the exported environment from the exported
 * names in the dictionary. Keyword assignments
 * will already have been done.
 */
static char **
makenv()

{
	register struct wdblock *wb;
	register struct var *vp;

	wb = NULL;
	for (vp = vlist; vp; vp = vp->next)
		if (vp->status & EXPORT)
			wb = addword(vp->name, wb);
	wb = addword((char *)0, wb);
	return(getwords(wb));
}

static char *
evalstr(cp, f)
register char *cp;
int f;
{
	struct wdblock *wb;

	wb = NULL;
	if (expand(cp, &wb, f)) {
		if (wb == NULL || wb->w_nword == 0 || (cp = wb->w_words[0]) == NULL)
			cp = "";
		DELETE(wb);
	} else
		cp = NULL;
	return(cp);
}

static int
expand( char *cp, register struct wdblock **wbp, int f)
{
	jmp_buf ev;

#if __GNUC__
	/* Avoid longjmp clobbering */
	(void) &cp;
#endif
	gflg = 0;
	if (cp == NULL)
		return(0);
	if (!anys("$`'\"", cp) &&
	    !anys(ifs->value, cp) &&
	    ((f&DOGLOB)==0 || !anys("[*?", cp))) {
		cp = strsave(cp, areanum);
		if (f & DOTRIM)
			unquote(cp);
		*wbp = addword(cp, *wbp);
		return(1);
	}
	if (newenv(setjmp(errpt = ev)) == 0) {
		PUSHIO(aword, cp, strchar);
		e.iobase = e.iop;
		while ((cp = blank(f)) && gflg == 0) {
			e.linep = cp;
			cp = strsave(cp, areanum);
			if ((f&DOGLOB) == 0) {
				if (f & DOTRIM)
					unquote(cp);
				*wbp = addword(cp, *wbp);
			} else
				*wbp = glob(cp, *wbp);
		}
		quitenv();
	} else
		gflg = 1;
	return(gflg == 0);
}

/*
 * Blank interpretation and quoting
 */
static char *
blank(f)
int f;
{
	register int c, c1;
	register char *sp;
	int scanequals, foundequals;

	sp = e.linep;
	scanequals = f & DOKEY;
	foundequals = 0;

loop:
	switch (c = subgetc('"', foundequals)) {
	case 0:
		if (sp == e.linep)
			return(0);
		*e.linep++ = 0;
		retur