1/*	$OpenBSD: main.c,v 1.54 2013/11/28 10:33:37 sobrado Exp $	*/
2/*	$OpenBSD: tty.c,v 1.10 2014/08/10 02:44:26 guenther Exp $	*/
3/*	$OpenBSD: io.c,v 1.25 2014/08/11 20:28:47 guenther Exp $	*/
4/*	$OpenBSD: table.c,v 1.15 2012/02/19 07:52:30 otto Exp $	*/
5
6/*-
7 * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
8 *		 2011, 2012, 2013, 2014
9 *	Thorsten Glaser <tg@mirbsd.org>
10 *
11 * Provided that these terms and disclaimer and all copyright notices
12 * are retained or reproduced in an accompanying document, permission
13 * is granted to deal in this work without restriction, including un-
14 * limited rights to use, publicly perform, distribute, sell, modify,
15 * merge, give away, or sublicence.
16 *
17 * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to
18 * the utmost extent permitted by applicable law, neither express nor
19 * implied; without malicious intent or gross negligence. In no event
20 * may a licensor, author or contributor be held liable for indirect,
21 * direct, other damage, loss, or other issues arising in any way out
22 * of dealing in the work, even if advised of the possibility of such
23 * damage or existence of a defect, except proven that it results out
24 * of said person's immediate fault when using the work as intended.
25 */
26
27#define EXTERN
28#include "sh.h"
29
30#if HAVE_LANGINFO_CODESET
31#include <langinfo.h>
32#endif
33#if HAVE_SETLOCALE_CTYPE
34#include <locale.h>
35#endif
36
37__RCSID("$MirOS: src/bin/mksh/main.c,v 1.284 2014/10/03 17:19:27 tg Exp $");
38
39extern char **environ;
40
41#ifndef MKSHRC_PATH
42#define MKSHRC_PATH	"~/.mkshrc"
43#endif
44
45#ifndef MKSH_DEFAULT_TMPDIR
46#define MKSH_DEFAULT_TMPDIR	"/tmp"
47#endif
48
49static uint8_t isuc(const char *);
50static int main_init(int, const char *[], Source **, struct block **);
51void chvt_reinit(void);
52static void reclaim(void);
53static void remove_temps(struct temp *);
54static mksh_uari_t rndsetup(void);
55#ifdef SIGWINCH
56static void x_sigwinch(int);
57#endif
58
59static const char initifs[] = "IFS= \t\n";
60
61static const char initsubs[] =
62    "${PS2=> } ${PS3=#? } ${PS4=+ } ${SECONDS=0} ${TMOUT=0} ${EPOCHREALTIME=}";
63
64static const char *initcoms[] = {
65	Ttypeset, "-r", initvsn, NULL,
66	Ttypeset, "-x", "HOME", "PATH", "SHELL", NULL,
67	Ttypeset, "-i10", "COLUMNS", "LINES", "SECONDS", "TMOUT", NULL,
68	Talias,
69	"integer=typeset -i",
70	Tlocal_typeset,
71	/* not "alias -t --": hash -r needs to work */
72	"hash=alias -t",
73	"type=whence -v",
74#if !defined(ANDROID) && !defined(MKSH_UNEMPLOYED)
75	/* not in Android for political reasons */
76	/* not in ARGE mksh due to no job control */
77	"stop=kill -STOP",
78#endif
79	"autoload=typeset -fu",
80	"functions=typeset -f",
81	"history=fc -l",
82	"nameref=typeset -n",
83	"nohup=nohup ",
84	Tr_fc_e_dash,
85	"source=PATH=$PATH:. command .",
86	"login=exec login",
87	NULL,
88	 /* this is what AT&T ksh seems to track, with the addition of emacs */
89	Talias, "-tU",
90	"cat", "cc", "chmod", "cp", "date", "ed", "emacs", "grep", "ls",
91	"make", "mv", "pr", "rm", "sed", "sh", "vi", "who", NULL,
92	NULL
93};
94
95static const char *restr_com[] = {
96	Ttypeset, "-r", "PATH", "ENV", "SHELL", NULL
97};
98
99static bool initio_done;
100
101/* top-level parsing and execution environment */
102static struct env env;
103struct env *e = &env;
104
105static mksh_uari_t
106rndsetup(void)
107{
108	register uint32_t h;
109	struct {
110		ALLOC_ITEM alloc_INT;
111		void *dataptr, *stkptr, *mallocptr;
112#if defined(__GLIBC__) && (__GLIBC__ >= 2)
113		sigjmp_buf jbuf;
114#endif
115		struct timeval tv;
116	} *bufptr;
117	char *cp;
118
119	cp = alloc(sizeof(*bufptr) - ALLOC_SIZE, APERM);
120#ifdef DEBUG
121	/* clear the allocated space, for valgrind */
122	memset(cp, 0, sizeof(*bufptr) - ALLOC_SIZE);
123#endif
124	/* undo what alloc() did to the malloc result address */
125	bufptr = (void *)(cp - ALLOC_SIZE);
126	/* PIE or something similar provides us with deltas here */
127	bufptr->dataptr = &rndsetupstate;
128	/* ASLR in at least Windows, Linux, some BSDs */
129	bufptr->stkptr = &bufptr;
130	/* randomised malloc in BSD (and possibly others) */
131	bufptr->mallocptr = bufptr;
132#if defined(__GLIBC__) && (__GLIBC__ >= 2)
133	/* glibc pointer guard */
134	sigsetjmp(bufptr->jbuf, 1);
135#endif
136	/* introduce variation (and yes, second arg MBZ for portability) */
137	mksh_TIME(bufptr->tv);
138
139	h = chvt_rndsetup(bufptr, sizeof(*bufptr));
140
141	afree(cp, APERM);
142	return ((mksh_uari_t)h);
143}
144
145void
146chvt_reinit(void)
147{
148	kshpid = procpid = getpid();
149	ksheuid = geteuid();
150	kshpgrp = getpgrp();
151	kshppid = getppid();
152}
153
154static const char *empty_argv[] = {
155	"mksh", NULL
156};
157
158static uint8_t
159isuc(const char *cx) {
160	char *cp, *x;
161	uint8_t rv = 0;
162
163	if (!cx || !*cx)
164		return (0);
165
166	/* uppercase a string duplicate */
167	strdupx(x, cx, ATEMP);
168	cp = x;
169	while ((*cp = ksh_toupper(*cp)))
170		++cp;
171
172	/* check for UTF-8 */
173	if (strstr(x, "UTF-8") || strstr(x, "UTF8"))
174		rv = 1;
175
176	/* free copy and out */
177	afree(x, ATEMP);
178	return (rv);
179}
180
181static int
182main_init(int argc, const char *argv[], Source **sp, struct block **lp)
183{
184	int argi, i;
185	Source *s = NULL;
186	struct block *l;
187	unsigned char restricted_shell, errexit, utf_flag;
188	char *cp;
189	const char *ccp, **wp;
190	struct tbl *vp;
191	struct stat s_stdin;
192#if !defined(_PATH_DEFPATH) && defined(_CS_PATH)
193	ssize_t k;
194#endif
195
196	/* do things like getpgrp() et al. */
197	chvt_reinit();
198
199	/* make sure argv[] is sane */
200	if (!*argv) {
201		argv = empty_argv;
202		argc = 1;
203	}
204	kshname = argv[0];
205
206	/* initialise permanent Area */
207	ainit(&aperm);
208
209	/* set up base environment */
210	env.type = E_NONE;
211	ainit(&env.area);
212	/* set up global l->vars and l->funs */
213	newblock();
214
215	/* Do this first so output routines (eg, errorf, shellf) can work */
216	initio();
217
218	/* determine the basename (without '-' or path) of the executable */
219	ccp = kshname;
220	goto begin_parse_kshname;
221	while ((i = ccp[argi++])) {
222		if (i == '/') {
223			ccp += argi;
224 begin_parse_kshname:
225			argi = 0;
226			if (*ccp == '-')
227				++ccp;
228		}
229	}
230	if (!*ccp)
231		ccp = empty_argv[0];
232
233	/*
234	 * Turn on nohup by default. (AT&T ksh does not have a nohup
235	 * option - it always sends the hup).
236	 */
237	Flag(FNOHUP) = 1;
238
239	/*
240	 * Turn on brace expansion by default. AT&T kshs that have
241	 * alternation always have it on.
242	 */
243	Flag(FBRACEEXPAND) = 1;
244
245	/*
246	 * Turn on "set -x" inheritance by default.
247	 */
248	Flag(FXTRACEREC) = 1;
249
250	/* define built-in commands and see if we were called as one */
251	ktinit(APERM, &builtins,
252	    /* currently up to 51 builtins: 75% of 128 = 2^7 */
253	    7);
254	for (i = 0; mkshbuiltins[i].name != NULL; i++)
255		if (!strcmp(ccp, builtin(mkshbuiltins[i].name,
256		    mkshbuiltins[i].func)))
257			Flag(FAS_BUILTIN) = 1;
258
259	if (!Flag(FAS_BUILTIN)) {
260		/* check for -T option early */
261		argi = parse_args(argv, OF_FIRSTTIME, NULL);
262		if (argi < 0)
263			return (1);
264
265#if defined(MKSH_BINSHPOSIX) || defined(MKSH_BINSHREDUCED)
266		/* are we called as -sh or /bin/sh or so? */
267		if (!strcmp(ccp, "sh")) {
268			/* either also turns off braceexpand */
269#ifdef MKSH_BINSHPOSIX
270			/* enable better POSIX conformance */
271			change_flag(FPOSIX, OF_FIRSTTIME, true);
272#endif
273#ifdef MKSH_BINSHREDUCED
274			/* enable kludge/compat mode */
275			change_flag(FSH, OF_FIRSTTIME, true);
276#endif
277		}
278#endif
279	}
280
281	initvar();
282
283	initctypes();
284
285	inittraps();
286
287	coproc_init();
288
289	/* set up variable and command dictionaries */
290	ktinit(APERM, &taliases, 0);
291	ktinit(APERM, &aliases, 0);
292#ifndef MKSH_NOPWNAM
293	ktinit(APERM, &homedirs, 0);
294#endif
295
296	/* define shell keywords */
297	initkeywords();
298
299	init_histvec();
300
301	/* initialise tty size before importing environment */
302	change_winsz();
303
304#ifdef _PATH_DEFPATH
305	def_path = _PATH_DEFPATH;
306#else
307#ifdef _CS_PATH
308	if ((k = confstr(_CS_PATH, NULL, 0)) > 0 &&
309	    confstr(_CS_PATH, cp = alloc(k + 1, APERM), k + 1) == k + 1)
310		def_path = cp;
311	else
312#endif
313		/*
314		 * this is uniform across all OSes unless it
315		 * breaks somewhere; don't try to optimise,
316		 * e.g. add stuff for Interix or remove /usr
317		 * for HURD, because e.g. Debian GNU/HURD is
318		 * "keeping a regular /usr"; this is supposed
319		 * to be a sane 'basic' default PATH
320		 */
321		def_path = "/bin:/usr/bin:/sbin:/usr/sbin";
322#endif
323
324	/*
325	 * Set PATH to def_path (will set the path global variable).
326	 * (import of environment below will probably change this setting).
327	 */
328	vp = global("PATH");
329	/* setstr can't fail here */
330	setstr(vp, def_path, KSH_RETURN_ERROR);
331
332#ifndef MKSH_NO_CMDLINE_EDITING
333	/*
334	 * Set edit mode to emacs by default, may be overridden
335	 * by the environment or the user. Also, we want tab completion
336	 * on in vi by default.
337	 */
338	change_flag(FEMACS, OF_SPECIAL, true);
339#if !MKSH_S_NOVI
340	Flag(FVITABCOMPLETE) = 1;
341#endif
342#endif
343
344	/* import environment */
345	if (environ != NULL) {
346		wp = (const char **)environ;
347		while (*wp != NULL) {
348			rndpush(*wp);
349			typeset(*wp, IMPORT | EXPORT, 0, 0, 0);
350			++wp;
351		}
352	}
353
354	/* for security */
355	typeset(initifs, 0, 0, 0, 0);
356
357	/* assign default shell variable values */
358	substitute(initsubs, 0);
359
360	/* Figure out the current working directory and set $PWD */
361	vp = global("PWD");
362	cp = str_val(vp);
363	/* Try to use existing $PWD if it is valid */
364	set_current_wd((cp[0] == '/' && test_eval(NULL, TO_FILEQ, cp, ".",
365	    true)) ? cp : NULL);
366	if (current_wd[0])
367		simplify_path(current_wd);
368	/* Only set pwd if we know where we are or if it had a bogus value */
369	if (current_wd[0] || *cp)
370		/* setstr can't fail here */
371		setstr(vp, current_wd, KSH_RETURN_ERROR);
372
373	for (wp = initcoms; *wp != NULL; wp++) {
374		shcomexec(wp);
375		while (*wp != NULL)
376			wp++;
377	}
378	setint_n(global("OPTIND"), 1, 10);
379
380	kshuid = getuid();
381	kshgid = getgid();
382	kshegid = getegid();
383
384	safe_prompt = ksheuid ? "$ " : "# ";
385	vp = global("PS1");
386	/* Set PS1 if unset or we are root and prompt doesn't contain a # */
387	if (!(vp->flag & ISSET) ||
388	    (!ksheuid && !strchr(str_val(vp), '#')))
389		/* setstr can't fail here */
390		setstr(vp, safe_prompt, KSH_RETURN_ERROR);
391	setint_n((vp = global("BASHPID")), 0, 10);
392	vp->flag |= INT_U;
393	setint_n((vp = global("PGRP")), (mksh_uari_t)kshpgrp, 10);
394	vp->flag |= INT_U;
395	setint_n((vp = global("PPID")), (mksh_uari_t)kshppid, 10);
396	vp->flag |= INT_U;
397	setint_n((vp = global("USER_ID")), (mksh_uari_t)ksheuid, 10);
398	vp->flag |= INT_U;
399	setint_n((vp = global("KSHUID")), (mksh_uari_t)kshuid, 10);
400	vp->flag |= INT_U;
401	setint_n((vp = global("KSHEGID")), (mksh_uari_t)kshegid, 10);
402	vp->flag |= INT_U;
403	setint_n((vp = global("KSHGID")), (mksh_uari_t)kshgid, 10);
404	vp->flag |= INT_U;
405	setint_n((vp = global("RANDOM")), rndsetup(), 10);
406	vp->flag |= INT_U;
407	setint_n((vp_pipest = global("PIPESTATUS")), 0, 10);
408
409	/* Set this before parsing arguments */
410	Flag(FPRIVILEGED) = (
411#if HAVE_ISSETUGID
412	    issetugid() ||
413#endif
414	    kshuid != ksheuid || kshgid != kshegid) ? 2 : 0;
415
416	/* this to note if monitor is set on command line (see below) */
417#ifndef MKSH_UNEMPLOYED
418	Flag(FMONITOR) = 127;
419#endif
420	/* this to note if utf-8 mode is set on command line (see below) */
421	UTFMODE = 2;
422
423	if (!Flag(FAS_BUILTIN)) {
424		argi = parse_args(argv, OF_CMDLINE, NULL);
425		if (argi < 0)
426			return (1);
427	}
428
429	/* process this later only, default to off (hysterical raisins) */
430	utf_flag = UTFMODE;
431	UTFMODE = 0;
432
433	if (Flag(FAS_BUILTIN)) {
434		/* auto-detect from environment variables, always */
435		utf_flag = 3;
436	} else if (Flag(FCOMMAND)) {
437		s = pushs(SSTRINGCMDLINE, ATEMP);
438		if (!(s->start = s->str = argv[argi++]))
439			errorf("%s %s", "-c", "requires an argument");
440		while (*s->str) {
441			if (*s->str != ' ' && ctype(*s->str, C_QUOTE))
442				break;
443			s->str++;
444		}
445		if (!*s->str)
446			s->flags |= SF_MAYEXEC;
447		s->str = s->start;
448#ifdef MKSH_MIDNIGHTBSD01ASH_COMPAT
449		/* compatibility to MidnightBSD 0.1 /bin/sh (kludge) */
450		if (Flag(FSH) && argv[argi] && !strcmp(argv[argi], "--"))
451			++argi;
452#endif
453		if (argv[argi])
454			kshname = argv[argi++];
455	} else if (argi < argc && !Flag(FSTDIN)) {
456		s = pushs(SFILE, ATEMP);
457		s->file = argv[argi++];
458		s->u.shf = shf_open(s->file, O_RDONLY, 0,
459		    SHF_MAPHI | SHF_CLEXEC);
460		if (s->u.shf == NULL) {
461			shl_stdout_ok = false;
462			warningf(true, "%s: %s", s->file, cstrerror(errno));
463			/* mandated by SUSv4 */
464			exstat = 127;
465			unwind(LERROR);
466		}
467		kshname = s->file;
468	} else {
469		Flag(FSTDIN) = 1;
470		s = pushs(SSTDIN, ATEMP);
471		s->file = "<stdin>";
472		s->u.shf = shf_fdopen(0, SHF_RD | can_seek(0),
473		    NULL);
474		if (isatty(0) && isatty(2)) {
475			Flag(FTALKING) = Flag(FTALKING_I) = 1;
476			/* The following only if isatty(0) */
477			s->flags |= SF_TTY;
478			s->u.shf->flags |= SHF_INTERRUPT;
479			s->file = NULL;
480		}
481	}
482
483	/* this bizarreness is mandated by POSIX */
484	if (fstat(0, &s_stdin) >= 0 && S_ISCHR(s_stdin.st_mode) &&
485	    Flag(FTALKING))
486		reset_nonblock(0);
487
488	/* initialise job control */
489	j_init();
490	/* do this after j_init() which calls tty_init_state() */
491	if (Flag(FTALKING)) {
492		if (utf_flag == 2) {
493#ifndef MKSH_ASSUME_UTF8
494			/* auto-detect from locale or environment */
495			utf_flag = 4;
496#else /* this may not be an #elif */
497#if MKSH_ASSUME_UTF8
498			utf_flag = 1;
499#else
500			/* always disable UTF-8 (for interactive) */
501			utf_flag = 0;
502#endif
503#endif
504		}
505#ifndef MKSH_NO_CMDLINE_EDITING
506		x_init();
507#endif
508	}
509
510#ifdef SIGWINCH
511	sigtraps[SIGWINCH].flags |= TF_SHELL_USES;
512	setsig(&sigtraps[SIGWINCH], x_sigwinch,
513	    SS_RESTORE_ORIG|SS_FORCE|SS_SHTRAP);
514#endif
515
516	l = e->loc;
517	if (Flag(FAS_BUILTIN)) {
518		l->argc = argc;
519		l->argv = argv;
520		l->argv[0] = ccp;
521	} else {
522		l->argc = argc - argi;
523		/*
524		 * allocate a new array because otherwise, when we modify
525		 * it in-place, ps(1) output changes; the meaning of argc
526		 * here is slightly different as it excludes kshname, and
527		 * we add a trailing NULL sentinel as well
528		 */
529		l->argv = alloc2(l->argc + 2, sizeof(void *), APERM);
530		l->argv[0] = kshname;
531		memcpy(&l->argv[1], &argv[argi], l->argc * sizeof(void *));
532		l->argv[l->argc + 1] = NULL;
533		getopts_reset(1);
534	}
535
536	/* divine the initial state of the utf8-mode Flag */
537	ccp = null;
538	switch (utf_flag) {
539
540	/* auto-detect from locale or environment */
541	case 4:
542#if HAVE_SETLOCALE_CTYPE
543		ccp = setlocale(LC_CTYPE, "");
544#if HAVE_LANGINFO_CODESET
545		if (!isuc(ccp))
546			ccp = nl_langinfo(CODESET);
547#endif
548		if (!isuc(ccp))
549			ccp = null;
550		/* FALLTHROUGH */
551#endif
552
553	/* auto-detect from environment */
554	case 3:
555		/* these were imported from environ earlier */
556		if (ccp == null)
557			ccp = str_val(global("LC_ALL"));
558		if (ccp == null)
559			ccp = str_val(global("LC_CTYPE"));
560		if (ccp == null)
561			ccp = str_val(global("LANG"));
562		UTFMODE = isuc(ccp);
563		break;
564
565	/* not set on command line, not FTALKING */
566	case 2:
567	/* unknown values */
568	default:
569		utf_flag = 0;
570		/* FALLTHROUGH */
571
572	/* known values */
573	case 1:
574	case 0:
575		UTFMODE = utf_flag;
576		break;
577	}
578
579	/* Disable during .profile/ENV reading */
580	restricted_shell = Flag(FRESTRICTED);
581	Flag(FRESTRICTED) = 0;
582	errexit = Flag(FERREXIT);
583	Flag(FERREXIT) = 0;
584
585	/*
586	 * Do this before profile/$ENV so that if it causes problems in them,
587	 * user will know why things broke.
588	 */
589	if (!current_wd[0] && Flag(FTALKING))
590		warningf(false, "can't determine current directory");
591
592	if (Flag(FLOGIN))
593		include(MKSH_SYSTEM_PROFILE, 0, NULL, true);
594	if (!Flag(FPRIVILEGED)) {
595		if (Flag(FLOGIN))
596			include(substitute("$HOME/.profile", 0), 0, NULL, true);
597		if (Flag(FTALKING)) {
598			cp = substitute(substitute("${ENV:-" MKSHRC_PATH "}",
599			    0), DOTILDE);
600			if (cp[0] != '\0')
601				include(cp, 0, NULL, true);
602		}
603	} else {
604		include(MKSH_SUID_PROFILE, 0, NULL, true);
605		/* turn off -p if not set explicitly */
606		if (Flag(FPRIVILEGED) != 1)
607			change_flag(FPRIVILEGED, OF_INTERNAL, false);
608	}
609
610	if (restricted_shell) {
611		shcomexec(restr_com);
612		/* After typeset command... */
613		Flag(FRESTRICTED) = 1;
614	}
615	Flag(FERREXIT) = errexit;
616
617	if (Flag(FTALKING) && s)
618		hist_init(s);
619	else
620		/* set after ENV */
621		Flag(FTRACKALL) = 1;
622
623	alarm_init();
624
625	*sp = s;
626	*lp = l;
627	return (0);
628}
629
630/* this indirection barrier reduces stack usage during normal operation */
631
632int
633main(int argc, const char *argv[])
634{
635	int rv;
636	Source *s;
637	struct block *l;
638
639	if ((rv = main_init(argc, argv, &s, &l)) == 0) {
640		if (Flag(FAS_BUILTIN)) {
641			rv = shcomexec(l->argv);
642		} else {
643			shell(s, true);
644			/* NOTREACHED */
645		}
646	}
647	return (rv);
648}
649
650int
651include(const char *name, int argc, const char **argv, bool intr_ok)
652{
653	Source *volatile s = NULL;
654	struct shf *shf;
655	const char **volatile old_argv;
656	volatile int old_argc;
657	int i;
658
659	shf = shf_open(name, O_RDONLY, 0, SHF_MAPHI | SHF_CLEXEC);
660	if (shf == NULL)
661		return (-1);
662
663	if (argv) {
664		old_argv = e->loc->argv;
665		old_argc = e->loc->argc;
666	} else {
667		old_argv = NULL;
668		old_argc = 0;
669	}
670	newenv(E_INCL);
671	if ((i = kshsetjmp(e->jbuf))) {
672		quitenv(s ? s->u.shf : NULL);
673		if (old_argv) {
674			e->loc->argv = old_argv;
675			e->loc->argc = old_argc;
676		}
677		switch (i) {
678		case LRETURN:
679		case LERROR:
680			/* see below */
681			return (exstat & 0xFF);
682		case LINTR:
683			/*
684			 * intr_ok is set if we are including .profile or $ENV.
685			 * If user ^Cs out, we don't want to kill the shell...
686			 */
687			if (intr_ok && ((exstat & 0xFF) - 128) != SIGTERM)
688				return (1);
689			/* FALLTHROUGH */
690		case LEXIT:
691		case LLEAVE:
692		case LSHELL:
693			unwind(i);
694			/* NOTREACHED */
695		default:
696			internal_errorf("%s %d", "include", i);
697			/* NOTREACHED */
698		}
699	}
700	if (argv) {
701		e->loc->argv = argv;
702		e->loc->argc = argc;
703	}
704	s = pushs(SFILE, ATEMP);
705	s->u.shf = shf;
706	strdupx(s->file, name, ATEMP);
707	i = shell(s, false);
708	quitenv(s->u.shf);
709	if (old_argv) {
710		e->loc->argv = old_argv;
711		e->loc->argc = old_argc;
712	}
713	/* & 0xff to ensure value not -1 */
714	return (i & 0xFF);
715}
716
717/* spawn a command into a shell optionally keeping track of the line number */
718int
719command(const char *comm, int line)
720{
721	Source *s;
722
723	s = pushs(SSTRING, ATEMP);
724	s->start = s->str = comm;
725	s->line = line;
726	return (shell(s, false));
727}
728
729/*
730 * run the commands from the input source, returning status.
731 */
732int
733shell(Source * volatile s, volatile bool toplevel)
734{
735	struct op *t;
736	volatile bool wastty = tobool(s->flags & SF_TTY);
737	volatile uint8_t attempts = 13;
738	volatile bool interactive = Flag(FTALKING) && toplevel;
739	volatile bool sfirst = true;
740	Source *volatile old_source = source;
741	int i;
742
743	newenv(E_PARSE);
744	if (interactive)
745		really_exit = false;
746	switch ((i = kshsetjmp(e->jbuf))) {
747	case 0:
748		break;
749	case LINTR:
750		/* we get here if SIGINT not caught or ignored */
751	case LERROR:
752	case LSHELL:
753		if (interactive) {
754			if (i == LINTR)
755				shellf("\n");
756			/*
757			 * Reset any eof that was read as part of a
758			 * multiline command.
759			 */
760			if (Flag(FIGNOREEOF) && s->type == SEOF && wastty)
761				s->type = SSTDIN;
762			/*
763			 * Used by exit command to get back to
764			 * top level shell. Kind of strange since
765			 * interactive is set if we are reading from
766			 * a tty, but to have stopped jobs, one only
767			 * needs FMONITOR set (not FTALKING/SF_TTY)...
768			 */
769			/* toss any input we have so far */
770			yyrecursive_pop(true);
771			s->start = s->str = null;
772			retrace_info = NULL;
773			herep = heres;
774			break;
775		}
776		/* FALLTHROUGH */
777	case LEXIT:
778	case LLEAVE:
779	case LRETURN:
780		source = old_source;
781		quitenv(NULL);
782		/* keep on going */
783		unwind(i);
784		/* NOTREACHED */
785	default:
786		source = old_source;
787		quitenv(NULL);
788		internal_errorf("%s %d", "shell", i);
789		/* NOTREACHED */
790	}
791	while (/* CONSTCOND */ 1) {
792		if (trap)
793			runtraps(0);
794
795		if (s->next == NULL) {
796			if (Flag(FVERBOSE))
797				s->flags |= SF_ECHO;
798			else
799				s->flags &= ~SF_ECHO;
800		}
801		if (interactive) {
802			j_notify();
803			set_prompt(PS1, s);
804		}
805		t = compile(s, sfirst);
806		sfirst = false;
807		if (!t)
808			goto source_no_tree;
809		if (t->type == TEOF) {
810			if (wastty && Flag(FIGNOREEOF) && --attempts > 0) {
811				shellf("Use 'exit' to leave mksh\n");
812				s->type = SSTDIN;
813			} else if (wastty && !really_exit &&
814			    j_stopped_running()) {
815				really_exit = true;
816				s->type = SSTDIN;
817			} else {
818				/*
819				 * this for POSIX which says EXIT traps
820				 * shall be taken in the environment
821				 * immediately after the last command
822				 * executed.
823				 */
824				if (toplevel)
825					unwind(LEXIT);
826				break;
827			}
828		} else if ((s->flags & SF_MAYEXEC) && t->type == TCOM)
829			t->u.evalflags |= DOTCOMEXEC;
830		if (!Flag(FNOEXEC) || (s->flags & SF_TTY))
831			exstat = execute(t, 0, NULL) & 0xFF;
832
833		if (t->type != TEOF && interactive && really_exit)
834			really_exit = false;
835
836 source_no_tree:
837		reclaim();
838	}
839	quitenv(NULL);
840	source = old_source;
841	return (exstat & 0xFF);
842}
843
844/* return to closest error handler or shell(), exit if none found */
845/* note: i MUST NOT be 0 */
846void
847unwind(int i)
848{
849	/*
850	 * This is a kludge. We need to restore everything that was
851	 * changed in the new environment, see cid 1005090337C7A669439
852	 * and 10050903386452ACBF1, but fail to even save things most of
853	 * the time. funcs.c:c_eval() changes FERREXIT temporarily to 0,
854	 * which needs to be restored thus (related to Debian #696823).
855	 * We did not save the shell flags, so we use a special or'd
856	 * value here... this is mostly to clean up behind *other*
857	 * callers of unwind(LERROR) here; exec.c has the regular case.
858	 */
859	if (Flag(FERREXIT) & 0x80) {
860		/* GNU bash does not run this trapsig */
861		trapsig(ksh_SIGERR);
862		Flag(FERREXIT) &= ~0x80;
863	}
864
865	/* ordering for EXIT vs ERR is a bit odd (this is what AT&T ksh does) */
866	if (i == LEXIT || ((i == LERROR || i == LINTR) &&
867	    sigtraps[ksh_SIGEXIT].trap &&
868	    (!Flag(FTALKING) || Flag(FERREXIT)))) {
869		++trap_nested;
870		runtrap(&sigtraps[ksh_SIGEXIT], trap_nested == 1);
871		--trap_nested;
872		i = LLEAVE;
873	} else if (Flag(FERREXIT) == 1 && (i == LERROR || i == LINTR)) {
874		++trap_nested;
875		runtrap(&sigtraps[ksh_SIGERR], trap_nested == 1);
876		--trap_nested;
877		i = LLEAVE;
878	}
879
880	while (/* CONSTCOND */ 1) {
881		switch (e->type) {
882		case E_PARSE:
883		case E_FUNC:
884		case E_INCL:
885		case E_LOOP:
886		case E_ERRH:
887			kshlongjmp(e->jbuf, i);
888			/* NOTREACHED */
889		case E_NONE:
890			if (i == LINTR)
891				e->flags |= EF_FAKE_SIGDIE;
892			/* FALLTHROUGH */
893		default:
894			quitenv(NULL);
895		}
896	}
897}
898
899void
900newenv(int type)
901{
902	struct env *ep;
903	char *cp;
904
905	/*
906	 * struct env includes ALLOC_ITEM for alignment constraints
907	 * so first get the actually used memory, then assign it
908	 */
909	cp = alloc(sizeof(struct env) - ALLOC_SIZE, ATEMP);
910	/* undo what alloc() did to the malloc result address */
911	ep = (void *)(cp - ALLOC_SIZE);
912	/* initialise public members of struct env (not the ALLOC_ITEM) */
913	ainit(&ep->area);
914	ep->oenv = e;
915	ep->loc = e->loc;
916	ep->savefd = NULL;
917	ep->temps = NULL;
918	ep->yyrecursive_statep = NULL;
919	ep->type = type;
920	ep->flags = 0;
921	/* jump buffer is invalid because flags == 0 */
922	e = ep;
923}
924
925void
926quitenv(struct shf *shf)
927{
928	struct env *ep = e;
929	char *cp;
930	int fd;
931
932	yyrecursive_pop(true);
933	while (ep->oenv && ep->oenv->loc != ep->loc)
934		popblock();
935	if (ep->savefd != NULL) {
936		for (fd = 0; fd < NUFILE; fd++)
937			/* if ep->savefd[fd] < 0, means fd was closed */
938			if (ep->savefd[fd])
939				restfd(fd, ep->savefd[fd]);
940		if (ep->savefd[2])
941			/* Clear any write errors */
942			shf_reopen(2, SHF_WR, shl_out);
943	}
944	/*
945	 * Bottom of the stack.
946	 * Either main shell is exiting or cleanup_parents_env() was called.
947	 */
948	if (ep->oenv == NULL) {
949#ifdef DEBUG_LEAKS
950		int i;
951#endif
952
953		if (ep->type == E_NONE) {
954			/* Main shell exiting? */
955#if HAVE_PERSISTENT_HISTORY
956			if (Flag(FTALKING))
957				hist_finish();
958#endif
959			j_exit();
960			if (ep->flags & EF_FAKE_SIGDIE) {
961				int sig = (exstat & 0xFF) - 128;
962
963				/*
964				 * ham up our death a bit (AT&T ksh
965				 * only seems to do this for SIGTERM)
966				 * Don't do it for SIGQUIT, since we'd
967				 * dump a core..
968				 */
969				if ((sig == SIGINT || sig == SIGTERM) &&
970				    (kshpgrp == kshpid)) {
971					setsig(&sigtraps[sig], SIG_DFL,
972					    SS_RESTORE_CURR | SS_FORCE);
973					kill(0, sig);
974				}
975			}
976		}
977		if (shf)
978			shf_close(shf);
979		reclaim();
980#ifdef DEBUG_LEAKS
981#ifndef MKSH_NO_CMDLINE_EDITING
982		x_done();
983#endif
984#ifndef MKSH_NOPROSPECTOFWORK
985		/* block at least SIGCHLD during/after afreeall */
986		sigprocmask(SIG_BLOCK, &sm_sigchld, NULL);
987#endif
988		afreeall(APERM);
989		for (fd = 3; fd < NUFILE; fd++)
990			if ((i = fcntl(fd, F_GETFD, 0)) != -1 &&
991			    (i & FD_CLOEXEC))
992				close(fd);
993		close(2);
994		close(1);
995		close(0);
996#endif
997		exit(exstat & 0xFF);
998	}
999	if (shf)
1000		shf_close(shf);
1001	reclaim();
1002
1003	e = e->oenv;
1004
1005	/* free the struct env - tricky due to the ALLOC_ITEM inside */
1006	cp = (void *)ep;
1007	afree(cp + ALLOC_SIZE, ATEMP);
1008}
1009
1010/* Called after a fork to cleanup stuff left over from parents environment */
1011void
1012cleanup_parents_env(void)
1013{
1014	struct env *ep;
1015	int fd;
1016
1017	mkssert(e != NULL);
1018
1019	/*
1020	 * Don't clean up temporary files - parent will probably need them.
1021	 * Also, can't easily reclaim memory since variables, etc. could be
1022	 * anywhere.
1023	 */
1024
1025	/* close all file descriptors hiding in savefd */
1026	for (ep = e; ep; ep = ep->oenv) {
1027		if (ep->savefd) {
1028			for (fd = 0; fd < NUFILE; fd++)
1029				if (ep->savefd[fd] > 0)
1030					close(ep->savefd[fd]);
1031			afree(ep->savefd, &ep->area);
1032			ep->savefd = NULL;
1033		}
1034#ifdef DEBUG_LEAKS
1035		if (ep->type != E_NONE)
1036			ep->type = E_GONE;
1037#endif
1038	}
1039#ifndef DEBUG_LEAKS
1040	e->oenv = NULL;
1041#endif
1042}
1043
1044/* Called just before an execve cleanup stuff temporary files */
1045void
1046cleanup_proc_env(void)
1047{
1048	struct env *ep;
1049
1050	for (ep = e; ep; ep = ep->oenv)
1051		remove_temps(ep->temps);
1052}
1053
1054/* remove temp files and free ATEMP Area */
1055static void
1056reclaim(void)
1057{
1058	struct block *l;
1059
1060	while ((l = e->loc) && (!e->oenv || e->oenv->loc != l)) {
1061		e->loc = l->next;
1062		afreeall(&l->area);
1063	}
1064
1065	remove_temps(e->temps);
1066	e->temps = NULL;
1067	afreeall(&e->area);
1068}
1069
1070static void
1071remove_temps(struct temp *tp)
1072{
1073	for (; tp != NULL; tp = tp->next)
1074		if (tp->pid == procpid)
1075			unlink(tp->tffn);
1076}
1077
1078/*
1079 * Initialise tty_fd. Used for tracking the size of the terminal,
1080 * saving/resetting tty modes upon forground job completion, and
1081 * for setting up the tty process group. Return values:
1082 *	0 = got controlling tty
1083 *	1 = got terminal but no controlling tty
1084 *	2 = cannot find a terminal
1085 *	3 = cannot dup fd
1086 *	4 = cannot make fd close-on-exec
1087 * An existing tty_fd is cached if no "better" one could be found,
1088 * i.e. if tty_devtty was already set or the new would not set it.
1089 */
1090int
1091tty_init_fd(void)
1092{
1093	int fd, rv, eno = 0;
1094	bool do_close = false, is_devtty = true;
1095
1096	if (tty_devtty) {
1097		/* already got a tty which is /dev/tty */
1098		return (0);
1099	}
1100
1101#ifdef _UWIN
1102	/*XXX imake style */
1103	if (isatty(3)) {
1104		/* fd 3 on UWIN _is_ /dev/tty (or our controlling tty) */
1105		fd = 3;
1106		goto got_fd;
1107	}
1108#endif
1109	if ((fd = open("/dev/tty", O_RDWR, 0)) >= 0) {
1110		do_close = true;
1111		goto got_fd;
1112	}
1113	eno = errno;
1114
1115	if (tty_fd >= 0) {
1116		/* already got a non-devtty one */
1117		rv = 1;
1118		goto out;
1119	}
1120	is_devtty = false;
1121
1122	if (isatty((fd = 0)) || isatty((fd = 2)))
1123		goto got_fd;
1124	/* cannot find one */
1125	rv = 2;
1126	/* assert: do_close == false */
1127	goto out;
1128
1129 got_fd:
1130	if ((rv = fcntl(fd, F_DUPFD, FDBASE)) < 0) {
1131		eno = errno;
1132		rv = 3;
1133		goto out;
1134	}
1135	if (fcntl(rv, F_SETFD, FD_CLOEXEC) < 0) {
1136		eno = errno;
1137		close(rv);
1138		rv = 4;
1139		goto out;
1140	}
1141	tty_fd = rv;
1142	tty_devtty = is_devtty;
1143	rv = eno = 0;
1144 out:
1145	if (do_close)
1146		close(fd);
1147	errno = eno;
1148	return (rv);
1149}
1150
1151/* A shell error occurred (eg, syntax error, etc.) */
1152
1153#define VWARNINGF_ERRORPREFIX	1
1154#define VWARNINGF_FILELINE	2
1155#define VWARNINGF_BUILTIN	4
1156#define VWARNINGF_INTERNAL	8
1157
1158static void vwarningf(unsigned int, const char *, va_list)
1159    MKSH_A_FORMAT(__printf__, 2, 0);
1160
1161static void
1162vwarningf(unsigned int flags, const char *fmt, va_list ap)
1163{
1164	if (fmt) {
1165		if (flags & VWARNINGF_INTERNAL)
1166			shf_fprintf(shl_out, "internal error: ");
1167		if (flags & VWARNINGF_ERRORPREFIX)
1168			error_prefix(tobool(flags & VWARNINGF_FILELINE));
1169		if ((flags & VWARNINGF_BUILTIN) &&
1170		    /* not set when main() calls parse_args() */
1171		    builtin_argv0 && builtin_argv0 != kshname)
1172			shf_fprintf(shl_out, "%s: ", builtin_argv0);
1173		shf_vfprintf(shl_out, fmt, ap);
1174		shf_putchar('\n', shl_out);
1175	}
1176	shf_flush(shl_out);
1177}
1178
1179void
1180errorfx(int rc, const char *fmt, ...)
1181{
1182	va_list va;
1183
1184	exstat = rc;
1185
1186	/* debugging: note that stdout not valid */
1187	shl_stdout_ok = false;
1188
1189	va_start(va, fmt);
1190	vwarningf(VWARNINGF_ERRORPREFIX | VWARNINGF_FILELINE, fmt, va);
1191	va_end(va);
1192	unwind(LERROR);
1193}
1194
1195void
1196errorf(const char *fmt, ...)
1197{
1198	va_list va;
1199
1200	exstat = 1;
1201
1202	/* debugging: note that stdout not valid */
1203	shl_stdout_ok = false;
1204
1205	va_start(va, fmt);
1206	vwarningf(VWARNINGF_ERRORPREFIX | VWARNINGF_FILELINE, fmt, va);
1207	va_end(va);
1208	unwind(LERROR);
1209}
1210
1211/* like errorf(), but no unwind is done */
1212void
1213warningf(bool fileline, const char *fmt, ...)
1214{
1215	va_list va;
1216
1217	va_start(va, fmt);
1218	vwarningf(VWARNINGF_ERRORPREFIX | (fileline ? VWARNINGF_FILELINE : 0),
1219	    fmt, va);
1220	va_end(va);
1221}
1222
1223/*
1224 * Used by built-in utilities to prefix shell and utility name to message
1225 * (also unwinds environments for special builtins).
1226 */
1227void
1228bi_errorf(const char *fmt, ...)
1229{
1230	va_list va;
1231
1232	/* debugging: note that stdout not valid */
1233	shl_stdout_ok = false;
1234
1235	exstat = 1;
1236
1237	va_start(va, fmt);
1238	vwarningf(VWARNINGF_ERRORPREFIX | VWARNINGF_FILELINE |
1239	    VWARNINGF_BUILTIN, fmt, va);
1240	va_end(va);
1241
1242	/*
1243	 * POSIX special builtins and ksh special builtins cause
1244	 * non-interactive shells to exit.
1245	 * XXX odd use of KEEPASN; also may not want LERROR here
1246	 */
1247	if (builtin_flag & SPEC_BI) {
1248		builtin_argv0 = NULL;
1249		unwind(LERROR);
1250	}
1251}
1252
1253/* Called when something that shouldn't happen does */
1254void
1255internal_errorf(const char *fmt, ...)
1256{
1257	va_list va;
1258
1259	va_start(va, fmt);
1260	vwarningf(VWARNINGF_INTERNAL, fmt, va);
1261	va_end(va);
1262	unwind(LERROR);
1263}
1264
1265void
1266internal_warningf(const char *fmt, ...)
1267{
1268	va_list va;
1269
1270	va_start(va, fmt);
1271	vwarningf(VWARNINGF_INTERNAL, fmt, va);
1272	va_end(va);
1273}
1274
1275/* used by error reporting functions to print "ksh: .kshrc[25]: " */
1276void
1277error_prefix(bool fileline)
1278{
1279	/* Avoid foo: foo[2]: ... */
1280	if (!fileline || !source || !source->file ||
1281	    strcmp(source->file, kshname) != 0)
1282		shf_fprintf(shl_out, "%s: ", kshname + (*kshname == '-'));
1283	if (fileline && source && source->file != NULL) {
1284		shf_fprintf(shl_out, "%s[%d]: ", source->file,
1285		    source->errline > 0 ? source->errline : source->line);
1286		source->errline = 0;
1287	}
1288}
1289
1290/* printf to shl_out (stderr) with flush */
1291void
1292shellf(const char *fmt, ...)
1293{
1294	va_list va;
1295
1296	if (!initio_done)
1297		/* shl_out may not be set up yet... */
1298		return;
1299	va_start(va, fmt);
1300	shf_vfprintf(shl_out, fmt, va);
1301	va_end(va);
1302	shf_flush(shl_out);
1303}
1304
1305/* printf to shl_stdout (stdout) */
1306void
1307shprintf(const char *fmt, ...)
1308{
1309	va_list va;
1310
1311	if (!shl_stdout_ok)
1312		internal_errorf("shl_stdout not valid");
1313	va_start(va, fmt);
1314	shf_vfprintf(shl_stdout, fmt, va);
1315	va_end(va);
1316}
1317
1318/* test if we can seek backwards fd (returns 0 or SHF_UNBUF) */
1319int
1320can_seek(int fd)
1321{
1322	struct stat statb;
1323
1324	return (fstat(fd, &statb) == 0 && !S_ISREG(statb.st_mode) ?
1325	    SHF_UNBUF : 0);
1326}
1327
1328#ifdef DF
1329int shl_dbg_fd;
1330#define NSHF_IOB 4
1331#else
1332#define NSHF_IOB 3
1333#endif
1334struct shf shf_iob[NSHF_IOB];
1335
1336void
1337initio(void)
1338{
1339#ifdef DF
1340	const char *lfp;
1341#endif
1342
1343	/* force buffer allocation */
1344	shf_fdopen(1, SHF_WR, shl_stdout);
1345	shf_fdopen(2, SHF_WR, shl_out);
1346	shf_fdopen(2, SHF_WR, shl_xtrace);
1347#ifdef DF
1348	if ((lfp = getenv("SDMKSH_PATH")) == NULL) {
1349		if ((lfp = getenv("HOME")) == NULL || *lfp != '/')
1350			errorf("cannot get home directory");
1351		lfp = shf_smprintf("%s/mksh-dbg.txt", lfp);
1352	}
1353
1354	if ((shl_dbg_fd = open(lfp, O_WRONLY | O_APPEND | O_CREAT, 0600)) < 0)
1355		errorf("cannot open debug output file %s", lfp);
1356	if (shl_dbg_fd < FDBASE) {
1357		int nfd;
1358
1359		nfd = fcntl(shl_dbg_fd, F_DUPFD, FDBASE);
1360		close(shl_dbg_fd);
1361		if ((shl_dbg_fd = nfd) == -1)
1362			errorf("cannot dup debug output file");
1363	}
1364	fcntl(shl_dbg_fd, F_SETFD, FD_CLOEXEC);
1365	shf_fdopen(shl_dbg_fd, SHF_WR, shl_dbg);
1366	DF("=== open ===");
1367#endif
1368	initio_done = true;
1369}
1370
1371/* A dup2() with error checking */
1372int
1373ksh_dup2(int ofd, int nfd, bool errok)
1374{
1375	int rv;
1376
1377	if (((rv = dup2(ofd, nfd)) < 0) && !errok && (errno != EBADF))
1378		errorf("too many files open in shell");
1379
1380#ifdef __ultrix
1381	/*XXX imake style */
1382	if (rv >= 0)
1383		fcntl(nfd, F_SETFD, 0);
1384#endif
1385
1386	return (rv);
1387}
1388
1389/*
1390 * Move fd from user space (0 <= fd < 10) to shell space (fd >= 10),
1391 * set close-on-exec flag. See FDBASE in sh.h, maybe 24 not 10 here.
1392 */
1393short
1394savefd(int fd)
1395{
1396	int nfd = fd;
1397
1398	if (fd < FDBASE && (nfd = fcntl(fd, F_DUPFD, FDBASE)) < 0 &&
1399	    errno == EBADF)
1400		return (-1);
1401	if (nfd < 0 || nfd > SHRT_MAX)
1402		errorf("too many files open in shell");
1403	fcntl(nfd, F_SETFD, FD_CLOEXEC);
1404	return ((short)nfd);
1405}
1406
1407void
1408restfd(int fd, int ofd)
1409{
1410	if (fd == 2)
1411		shf_flush(&shf_iob[/* fd */ 2]);
1412	if (ofd < 0)
1413		/* original fd closed */
1414		close(fd);
1415	else if (fd != ofd) {
1416		/*XXX: what to do if this dup fails? */
1417		ksh_dup2(ofd, fd, true);
1418		close(ofd);
1419	}
1420}
1421
1422void
1423openpipe(int *pv)
1424{
1425	int lpv[2];
1426
1427	if (pipe(lpv) < 0)
1428		errorf("can't create pipe - try again");
1429	pv[0] = savefd(lpv[0]);
1430	if (pv[0] != lpv[0])
1431		close(lpv[0]);
1432	pv[1] = savefd(lpv[1]);
1433	if (pv[1] != lpv[1])
1434		close(lpv[1]);
1435}
1436
1437void
1438closepipe(int *pv)
1439{
1440	close(pv[0]);
1441	close(pv[1]);
1442}
1443
1444/*
1445 * Called by iosetup() (deals with 2>&4, etc.), c_read, c_print to turn
1446 * a string (the X in 2>&X, read -uX, print -uX) into a file descriptor.
1447 */
1448int
1449check_fd(const char *name, int mode, const char **emsgp)
1450{
1451	int fd, fl;
1452
1453	if (name[0] == 'p' && !name[1])
1454		return (coproc_getfd(mode, emsgp));
1455	for (fd = 0; ksh_isdigit(*name); ++name)
1456		fd = (fd * 10) + *name - '0';
1457	if (*name || fd >= FDBASE) {
1458		if (emsgp)
1459			*emsgp = "illegal file descriptor name";
1460		return (-1);
1461	}
1462	if ((fl = fcntl(fd, F_GETFL, 0)) < 0) {
1463		if (emsgp)
1464			*emsgp = "bad file descriptor";
1465		return (-1);
1466	}
1467	fl &= O_ACCMODE;
1468	/*
1469	 * X_OK is a kludge to disable this check for dups (x<&1):
1470	 * historical shells never did this check (XXX don't know what
1471	 * POSIX has to say).
1472	 */
1473	if (!(mode & X_OK) && fl != O_RDWR && (
1474	    ((mode & R_OK) && fl != O_RDONLY) ||
1475	    ((mode & W_OK) && fl != O_WRONLY))) {
1476		if (emsgp)
1477			*emsgp = (fl == O_WRONLY) ?
1478			    "fd not open for reading" :
1479			    "fd not open for writing";
1480		return (-1);
1481	}
1482	return (fd);
1483}
1484
1485/* Called once from main */
1486void
1487coproc_init(void)
1488{
1489	coproc.read = coproc.readw = coproc.write = -1;
1490	coproc.njobs = 0;
1491	coproc.id = 0;
1492}
1493
1494/* Called by c_read() when eof is read - close fd if it is the co-process fd */
1495void
1496coproc_read_close(int fd)
1497{
1498	if (coproc.read >= 0 && fd == coproc.read) {
1499		coproc_readw_close(fd);
1500		close(coproc.read);
1501		coproc.read = -1;
1502	}
1503}
1504
1505/*
1506 * Called by c_read() and by iosetup() to close the other side of the
1507 * read pipe, so reads will actually terminate.
1508 */
1509void
1510coproc_readw_close(int fd)
1511{
1512	if (coproc.readw >= 0 && coproc.read >= 0 && fd == coproc.read) {
1513		close(coproc.readw);
1514		coproc.readw = -1;
1515	}
1516}
1517
1518/*
1519 * Called by c_print when a write to a fd fails with EPIPE and by iosetup
1520 * when co-process input is dup'd
1521 */
1522void
1523coproc_write_close(int fd)
1524{
1525	if (coproc.write >= 0 && fd == coproc.write) {
1526		close(coproc.write);
1527		coproc.write = -1;
1528	}
1529}
1530
1531/*
1532 * Called to check for existence of/value of the co-process file descriptor.
1533 * (Used by check_fd() and by c_read/c_print to deal with -p option).
1534 */
1535int
1536coproc_getfd(int mode, const char **emsgp)
1537{
1538	int fd = (mode & R_OK) ? coproc.read : coproc.write;
1539
1540	if (fd >= 0)
1541		return (fd);
1542	if (emsgp)
1543		*emsgp = "no coprocess";
1544	return (-1);
1545}
1546
1547/*
1548 * called to close file descriptors related to the coprocess (if any)
1549 * Should be called with SIGCHLD blocked.
1550 */
1551void
1552coproc_cleanup(int reuse)
1553{
1554	/* This to allow co-processes to share output pipe */
1555	if (!reuse || coproc.readw < 0 || coproc.read < 0) {
1556		if (coproc.read >= 0) {
1557			close(coproc.read);
1558			coproc.read = -1;
1559		}
1560		if (coproc.readw >= 0) {
1561			close(coproc.readw);
1562			coproc.readw = -1;
1563		}
1564	}
1565	if (coproc.write >= 0) {
1566		close(coproc.write);
1567		coproc.write = -1;
1568	}
1569}
1570
1571struct temp *
1572maketemp(Area *ap, Temp_type type, struct temp **tlist)
1573{
1574	char *cp;
1575	size_t len;
1576	int i, j;
1577	struct temp *tp;
1578	const char *dir;
1579	struct stat sb;
1580
1581	dir = tmpdir ? tmpdir : MKSH_DEFAULT_TMPDIR;
1582	/* add "/shXXXXXX.tmp" plus NUL */
1583	len = strlen(dir);
1584	checkoktoadd(len, offsetof(struct temp, tffn[0]) + 14);
1585	tp = alloc(offsetof(struct temp, tffn[0]) + 14 + len, ap);
1586
1587	tp->shf = NULL;
1588	tp->pid = procpid;
1589	tp->type = type;
1590
1591	if (stat(dir, &sb) || !S_ISDIR(sb.st_mode)) {
1592		tp->tffn[0] = '\0';
1593		goto maketemp_out;
1594	}
1595
1596	cp = (void *)tp;
1597	cp += offsetof(struct temp, tffn[0]);
1598	memcpy(cp, dir, len);
1599	cp += len;
1600	memcpy(cp, "/shXXXXXX.tmp", 14);
1601	/* point to the first of six Xes */
1602	cp += 3;
1603	/* generate random part of filename */
1604	len = -1;
1605	do {
1606		i = rndget() % 36;
1607		cp[++len] = i < 26 ? 'a' + i : '0' + i - 26;
1608	} while (len < 5);
1609
1610	/* cyclically attempt to open a temporary file */
1611	while ((i = open(tp->tffn, O_CREAT | O_EXCL | O_RDWR | O_BINARY,
1612	    0600)) < 0) {
1613		if (errno != EEXIST)
1614			goto maketemp_out;
1615		/* count down from z to a then from 9 to 0 */
1616		while (cp[len] == '0')
1617			if (!len--)
1618				goto maketemp_out;
1619		if (cp[len] == 'a')
1620			cp[len] = '9';
1621		else
1622			--cp[len];
1623		/* do another cycle */
1624	}
1625
1626	if (type == TT_FUNSUB) {
1627		/* map us high and mark as close-on-exec */
1628		if ((j = savefd(i)) != i) {
1629			close(i);
1630			i = j;
1631		}
1632
1633		/* operation mode for the shf */
1634		j = SHF_RD;
1635	} else
1636		j = SHF_WR;
1637
1638	/* shf_fdopen cannot fail, so no fd leak */
1639	tp->shf = shf_fdopen(i, j, NULL);
1640
1641 maketemp_out:
1642	tp->next = *tlist;
1643	*tlist = tp;
1644	return (tp);
1645}
1646
1647/*
1648 * We use a similar collision resolution algorithm as Python 2.5.4
1649 * but with a slightly tweaked implementation written from scratch.
1650 */
1651
1652#define	INIT_TBLSHIFT	3	/* initial table shift (2^3 = 8) */
1653#define PERTURB_SHIFT	5	/* see Python 2.5.4 Objects/dictobject.c */
1654
1655static void tgrow(struct table *);
1656static int tnamecmp(const void *, const void *);
1657
1658static void
1659tgrow(struct table *tp)
1660{
1661	size_t i, j, osize, mask, perturb;
1662	struct tbl *tblp, **pp;
1663	struct tbl **ntblp, **otblp = tp->tbls;
1664
1665	if (tp->tshift > 29)
1666		internal_errorf("hash table size limit reached");
1667
1668	/* calculate old size, new shift and new size */
1669	osize = (size_t)1 << (tp->tshift++);
1670	i = osize << 1;
1671
1672	ntblp = alloc2(i, sizeof(struct tbl *), tp->areap);
1673	/* multiplication cannot overflow: alloc2 checked that */
1674	memset(ntblp, 0, i * sizeof(struct tbl *));
1675
1676	/* table can get very full when reaching its size limit */
1677	tp->nfree = (tp->tshift == 30) ? 0x3FFF0000UL :
1678	    /* but otherwise, only 75% */
1679	    ((i * 3) / 4);
1680	tp->tbls = ntblp;
1681	if (otblp == NULL)
1682		return;
1683
1684	mask = i - 1;
1685	for (i = 0; i < osize; i++)
1686		if ((tblp = otblp[i]) != NULL) {
1687			if ((tblp->flag & DEFINED)) {
1688				/* search for free hash table slot */
1689				j = perturb = tblp->ua.hval;
1690				goto find_first_empty_slot;
1691 find_next_empty_slot:
1692				j = (j << 2) + j + perturb + 1;
1693				perturb >>= PERTURB_SHIFT;
1694 find_first_empty_slot:
1695				pp = &ntblp[j & mask];
1696				if (*pp != NULL)
1697					goto find_next_empty_slot;
1698				/* found an empty hash table slot */
1699				*pp = tblp;
1700				tp->nfree--;
1701			} else if (!(tblp->flag & FINUSE)) {
1702				afree(tblp, tp->areap);
1703			}
1704		}
1705	afree(otblp, tp->areap);
1706}
1707
1708void
1709ktinit(Area *ap, struct table *tp, uint8_t initshift)
1710{
1711	tp->areap = ap;
1712	tp->tbls = NULL;
1713	tp->tshift = ((initshift > INIT_TBLSHIFT) ?
1714	    initshift : INIT_TBLSHIFT) - 1;
1715	tgrow(tp);
1716}
1717
1718/* table, name (key) to search for, hash(name), rv pointer to tbl ptr */
1719struct tbl *
1720ktscan(struct table *tp, const char *name, uint32_t h, struct tbl ***ppp)
1721{
1722	size_t j, perturb, mask;
1723	struct tbl **pp, *p;
1724
1725	mask = ((size_t)1 << (tp->tshift)) - 1;
1726	/* search for hash table slot matching name */
1727	j = perturb = h;
1728	goto find_first_slot;
1729 find_next_slot:
1730	j = (j << 2) + j + perturb + 1;
1731	perturb >>= PERTURB_SHIFT;
1732 find_first_slot:
1733	pp = &tp->tbls[j & mask];
1734	if ((p = *pp) != NULL && (p->ua.hval != h || !(p->flag & DEFINED) ||
1735	    strcmp(p->name, name)))
1736		goto find_next_slot;
1737	/* p == NULL if not found, correct found entry otherwise */
1738	if (ppp)
1739		*ppp = pp;
1740	return (p);
1741}
1742
1743/* table, name (key) to enter, hash(n) */
1744struct tbl *
1745ktenter(struct table *tp, const char *n, uint32_t h)
1746{
1747	struct tbl **pp, *p;
1748	size_t len;
1749
1750 Search:
1751	if ((p = ktscan(tp, n, h, &pp)))
1752		return (p);
1753
1754	if (tp->nfree == 0) {
1755		/* too full */
1756		tgrow(tp);
1757		goto Search;
1758	}
1759
1760	/* create new tbl entry */
1761	len = strlen(n);
1762	checkoktoadd(len, offsetof(struct tbl, name[0]) + 1);
1763	p = alloc(offsetof(struct tbl, name[0]) + ++len, tp->areap);
1764	p->flag = 0;
1765	p->type = 0;
1766	p->areap = tp->areap;
1767	p->ua.hval = h;
1768	p->u2.field = 0;
1769	p->u.array = NULL;
1770	memcpy(p->name, n, len);
1771
1772	/* enter in tp->tbls */
1773	tp->nfree--;
1774	*pp = p;
1775	return (p);
1776}
1777
1778void
1779ktwalk(struct tstate *ts, struct table *tp)
1780{
1781	ts->left = (size_t)1 << (tp->tshift);
1782	ts->next = tp->tbls;
1783}
1784
1785struct tbl *
1786ktnext(struct tstate *ts)
1787{
1788	while (--ts->left >= 0) {
1789		struct tbl *p = *ts->next++;
1790		if (p != NULL && (p->flag & DEFINED))
1791			return (p);
1792	}
1793	return (NULL);
1794}
1795
1796static int
1797tnamecmp(const void *p1, const void *p2)
1798{
1799	const struct tbl *a = *((const struct tbl * const *)p1);
1800	const struct tbl *b = *((const struct tbl * const *)p2);
1801
1802	return (strcmp(a->name, b->name));
1803}
1804
1805struct tbl **
1806ktsort(struct table *tp)
1807{
1808	size_t i;
1809	struct tbl **p, **sp, **dp;
1810
1811	/*
1812	 * since the table is never entirely full, no need to reserve
1813	 * additional space for the trailing NULL appended below
1814	 */
1815	i = (size_t)1 << (tp->tshift);
1816	p = alloc2(i, sizeof(struct tbl *), ATEMP);
1817	sp = tp->tbls;		/* source */
1818	dp = p;			/* dest */
1819	while (i--)
1820		if ((*dp = *sp++) != NULL && (((*dp)->flag & DEFINED) ||
1821		    ((*dp)->flag & ARRAY)))
1822			dp++;
1823	qsort(p, (i = dp - p), sizeof(struct tbl *), tnamecmp);
1824	p[i] = NULL;
1825	return (p);
1826}
1827
1828#ifdef SIGWINCH
1829static void
1830x_sigwinch(int sig MKSH_A_UNUSED)
1831{
1832	/* this runs inside interrupt context, with errno saved */
1833
1834	got_winch = 1;
1835}
1836#endif
1837
1838#ifdef DF
1839void
1840DF(const char *fmt, ...)
1841{
1842	va_list args;
1843	struct timeval tv;
1844	mirtime_mjd mjd;
1845
1846	mksh_lockfd(shl_dbg_fd);
1847	mksh_TIME(tv);
1848	timet2mjd(&mjd, tv.tv_sec);
1849	shf_fprintf(shl_dbg, "[%02u:%02u:%02u (%u) %u.%06u] ",
1850	    (unsigned)mjd.sec / 3600, ((unsigned)mjd.sec / 60) % 60,
1851	    (unsigned)mjd.sec % 60, (unsigned)getpid(),
1852	    (unsigned)tv.tv_sec, (unsigned)tv.tv_usec);
1853	va_start(args, fmt);
1854	shf_vfprintf(shl_dbg, fmt, args);
1855	va_end(args);
1856	shf_putc('\n', shl_dbg);
1857	shf_flush(shl_dbg);
1858	mksh_unlkfd(shl_dbg_fd);
1859}
1860#endif
1861
1862void
1863x_mkraw(int fd, mksh_ttyst *ocb, bool forread)
1864{
1865	mksh_ttyst cb;
1866
1867	if (ocb)
1868		mksh_tcget(fd, ocb);
1869	else
1870		ocb = &tty_state;
1871
1872	cb = *ocb;
1873	if (forread) {
1874		cb.c_iflag &= ~(ISTRIP);
1875		cb.c_lflag &= ~(ICANON) | ECHO;
1876	} else {
1877		cb.c_iflag &= ~(INLCR | ICRNL | ISTRIP);
1878		cb.c_lflag &= ~(ISIG | ICANON | ECHO);
1879	}
1880#if defined(VLNEXT) && defined(_POSIX_VDISABLE)
1881	/* OSF/1 processes lnext when ~icanon */
1882	cb.c_cc[VLNEXT] = _POSIX_VDISABLE;
1883#endif
1884	/* SunOS 4.1.x & OSF/1 processes discard(flush) when ~icanon */
1885#if defined(VDISCARD) && defined(_POSIX_VDISABLE)
1886	cb.c_cc[VDISCARD] = _POSIX_VDISABLE;
1887#endif
1888	cb.c_cc[VTIME] = 0;
1889	cb.c_cc[VMIN] = 1;
1890
1891	mksh_tcset(fd, &cb);
1892}
1893