1 /* $OpenBSD: main.c,v 1.55 2015/02/09 09:09:30 jsg 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, 2015
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 1.285.2.4 2015/04/19 19:18:20 tg Exp $");
38
39 extern char **environ;
40
41 #ifndef MKSHRC_PATH
42 #define MKSHRC_PATH "~/.mkshrc"
43 #endif
44
45 #ifndef MKSH_DEFAULT_TMPDIR
46 #define MKSH_DEFAULT_TMPDIR "/tmp"
47 #endif
48
49 static uint8_t isuc(const char *);
50 static int main_init(int, const char *[], Source **, struct block **);
51 void chvt_reinit(void);
52 static void reclaim(void);
53 static void remove_temps(struct temp *);
54 static mksh_uari_t rndsetup(void);
55 #ifdef SIGWINCH
56 static void x_sigwinch(int);
57 #endif
58
59 static const char initifs[] = "IFS= \t\n";
60
61 static const char initsubs[] =
62 "${PS2=> } ${PS3=#? } ${PS4=+ } ${SECONDS=0} ${TMOUT=0} ${EPOCHREALTIME=}";
63
64 static const char *initcoms[] = {
65 Ttypeset, "-r", initvsn, NULL,
66 Ttypeset, "-x", "HOME", "PATH", "SHELL", NULL,
67 Ttypeset, "-i10", "COLUMNS", "LINES", "SECONDS", "TMOUT", NULL,
68 Talias,
69 "integer=typeset -i",
70 Tlocal_typeset,
71 /* not "alias -t --": hash -r needs to work */
72 "hash=alias -t",
73 "type=whence -v",
74 #if !defined(ANDROID) && !defined(MKSH_UNEMPLOYED)
75 /* not in Android for political reasons */
76 /* not in ARGE mksh due to no job control */
77 "stop=kill -STOP",
78 #endif
79 "autoload=typeset -fu",
80 "functions=typeset -f",
81 "history=fc -l",
82 "nameref=typeset -n",
83 "nohup=nohup ",
84 Tr_fc_e_dash,
85 "source=PATH=$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
95 static const char *restr_com[] = {
96 Ttypeset, "-r", "PATH", "ENV", "SHELL", NULL
97 };
98
99 static bool initio_done;
100
101 /* top-level parsing and execution environment */
102 static struct env env;
103 struct env *e = &env;
104
105 static mksh_uari_t
rndsetup(void)106 rndsetup(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
145 void
chvt_reinit(void)146 chvt_reinit(void)
147 {
148 kshpid = procpid = getpid();
149 ksheuid = geteuid();
150 kshpgrp = getpgrp();
151 kshppid = getppid();
152 }
153
154 static const char *empty_argv[] = {
155 "mksh", NULL
156 };
157
158 static uint8_t
isuc(const char * cx)159 isuc(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
181 static int
main_init(int argc,const char * argv[],Source ** sp,struct block ** lp)182 main_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
632 int
main(int argc,const char * argv[])633 main(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
650 int
include(const char * name,int argc,const char ** argv,bool intr_ok)651 include(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 */
718 int
command(const char * comm,int line)719 command(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 */
732 int
shell(Source * volatile s,volatile bool toplevel)733 shell(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 */
846 void
unwind(int i)847 unwind(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 * quitenv() may have reclaimed the memory
897 * used by source which will end badly when
898 * we jump to a function that expects it to
899 * be valid
900 */
901 source = NULL;
902 }
903 }
904 }
905
906 void
newenv(int type)907 newenv(int type)
908 {
909 struct env *ep;
910 char *cp;
911
912 /*
913 * struct env includes ALLOC_ITEM for alignment constraints
914 * so first get the actually used memory, then assign it
915 */
916 cp = alloc(sizeof(struct env) - ALLOC_SIZE, ATEMP);
917 /* undo what alloc() did to the malloc result address */
918 ep = (void *)(cp - ALLOC_SIZE);
919 /* initialise public members of struct env (not the ALLOC_ITEM) */
920 ainit(&ep->area);
921 ep->oenv = e;
922 ep->loc = e->loc;
923 ep->savefd = NULL;
924 ep->temps = NULL;
925 ep->yyrecursive_statep = NULL;
926 ep->type = type;
927 ep->flags = 0;
928 /* jump buffer is invalid because flags == 0 */
929 e = ep;
930 }
931
932 void
quitenv(struct shf * shf)933 quitenv(struct shf *shf)
934 {
935 struct env *ep = e;
936 char *cp;
937 int fd;
938
939 yyrecursive_pop(true);
940 while (ep->oenv && ep->oenv->loc != ep->loc)
941 popblock();
942 if (ep->savefd != NULL) {
943 for (fd = 0; fd < NUFILE; fd++)
944 /* if ep->savefd[fd] < 0, means fd was closed */
945 if (ep->savefd[fd])
946 restfd(fd, ep->savefd[fd]);
947 if (ep->savefd[2])
948 /* Clear any write errors */
949 shf_reopen(2, SHF_WR, shl_out);
950 }
951 /*
952 * Bottom of the stack.
953 * Either main shell is exiting or cleanup_parents_env() was called.
954 */
955 if (ep->oenv == NULL) {
956 #ifdef DEBUG_LEAKS
957 int i;
958 #endif
959
960 if (ep->type == E_NONE) {
961 /* Main shell exiting? */
962 #if HAVE_PERSISTENT_HISTORY
963 if (Flag(FTALKING))
964 hist_finish();
965 #endif
966 j_exit();
967 if (ep->flags & EF_FAKE_SIGDIE) {
968 int sig = (exstat & 0xFF) - 128;
969
970 /*
971 * ham up our death a bit (AT&T ksh
972 * only seems to do this for SIGTERM)
973 * Don't do it for SIGQUIT, since we'd
974 * dump a core..
975 */
976 if ((sig == SIGINT || sig == SIGTERM) &&
977 (kshpgrp == kshpid)) {
978 setsig(&sigtraps[sig], SIG_DFL,
979 SS_RESTORE_CURR | SS_FORCE);
980 kill(0, sig);
981 }
982 }
983 }
984 if (shf)
985 shf_close(shf);
986 reclaim();
987 #ifdef DEBUG_LEAKS
988 #ifndef MKSH_NO_CMDLINE_EDITING
989 x_done();
990 #endif
991 #ifndef MKSH_NOPROSPECTOFWORK
992 /* block at least SIGCHLD during/after afreeall */
993 sigprocmask(SIG_BLOCK, &sm_sigchld, NULL);
994 #endif
995 afreeall(APERM);
996 for (fd = 3; fd < NUFILE; fd++)
997 if ((i = fcntl(fd, F_GETFD, 0)) != -1 &&
998 (i & FD_CLOEXEC))
999 close(fd);
1000 close(2);
1001 close(1);
1002 close(0);
1003 #endif
1004 exit(exstat & 0xFF);
1005 }
1006 if (shf)
1007 shf_close(shf);
1008 reclaim();
1009
1010 e = e->oenv;
1011
1012 /* free the struct env - tricky due to the ALLOC_ITEM inside */
1013 cp = (void *)ep;
1014 afree(cp + ALLOC_SIZE, ATEMP);
1015 }
1016
1017 /* Called after a fork to cleanup stuff left over from parents environment */
1018 void
cleanup_parents_env(void)1019 cleanup_parents_env(void)
1020 {
1021 struct env *ep;
1022 int fd;
1023
1024 /*
1025 * Don't clean up temporary files - parent will probably need them.
1026 * Also, can't easily reclaim memory since variables, etc. could be
1027 * anywhere.
1028 */
1029
1030 /* close all file descriptors hiding in savefd */
1031 for (ep = e; ep; ep = ep->oenv) {
1032 if (ep->savefd) {
1033 for (fd = 0; fd < NUFILE; fd++)
1034 if (ep->savefd[fd] > 0)
1035 close(ep->savefd[fd]);
1036 afree(ep->savefd, &ep->area);
1037 ep->savefd = NULL;
1038 }
1039 #ifdef DEBUG_LEAKS
1040 if (ep->type != E_NONE)
1041 ep->type = E_GONE;
1042 #endif
1043 }
1044 #ifndef DEBUG_LEAKS
1045 e->oenv = NULL;
1046 #endif
1047 }
1048
1049 /* Called just before an execve cleanup stuff temporary files */
1050 void
cleanup_proc_env(void)1051 cleanup_proc_env(void)
1052 {
1053 struct env *ep;
1054
1055 for (ep = e; ep; ep = ep->oenv)
1056 remove_temps(ep->temps);
1057 }
1058
1059 /* remove temp files and free ATEMP Area */
1060 static void
reclaim(void)1061 reclaim(void)
1062 {
1063 struct block *l;
1064
1065 while ((l = e->loc) && (!e->oenv || e->oenv->loc != l)) {
1066 e->loc = l->next;
1067 afreeall(&l->area);
1068 }
1069
1070 remove_temps(e->temps);
1071 e->temps = NULL;
1072 afreeall(&e->area);
1073 }
1074
1075 static void
remove_temps(struct temp * tp)1076 remove_temps(struct temp *tp)
1077 {
1078 for (; tp != NULL; tp = tp->next)
1079 if (tp->pid == procpid)
1080 unlink(tp->tffn);
1081 }
1082
1083 /*
1084 * Initialise tty_fd. Used for tracking the size of the terminal,
1085 * saving/resetting tty modes upon forground job completion, and
1086 * for setting up the tty process group. Return values:
1087 * 0 = got controlling tty
1088 * 1 = got terminal but no controlling tty
1089 * 2 = cannot find a terminal
1090 * 3 = cannot dup fd
1091 * 4 = cannot make fd close-on-exec
1092 * An existing tty_fd is cached if no "better" one could be found,
1093 * i.e. if tty_devtty was already set or the new would not set it.
1094 */
1095 int
tty_init_fd(void)1096 tty_init_fd(void)
1097 {
1098 int fd, rv, eno = 0;
1099 bool do_close = false, is_devtty = true;
1100
1101 if (tty_devtty) {
1102 /* already got a tty which is /dev/tty */
1103 return (0);
1104 }
1105
1106 #ifdef _UWIN
1107 /*XXX imake style */
1108 if (isatty(3)) {
1109 /* fd 3 on UWIN _is_ /dev/tty (or our controlling tty) */
1110 fd = 3;
1111 goto got_fd;
1112 }
1113 #endif
1114 if ((fd = open("/dev/tty", O_RDWR, 0)) >= 0) {
1115 do_close = true;
1116 goto got_fd;
1117 }
1118 eno = errno;
1119
1120 if (tty_fd >= 0) {
1121 /* already got a non-devtty one */
1122 rv = 1;
1123 goto out;
1124 }
1125 is_devtty = false;
1126
1127 if (isatty((fd = 0)) || isatty((fd = 2)))
1128 goto got_fd;
1129 /* cannot find one */
1130 rv = 2;
1131 /* assert: do_close == false */
1132 goto out;
1133
1134 got_fd:
1135 if ((rv = fcntl(fd, F_DUPFD, FDBASE)) < 0) {
1136 eno = errno;
1137 rv = 3;
1138 goto out;
1139 }
1140 if (fcntl(rv, F_SETFD, FD_CLOEXEC) < 0) {
1141 eno = errno;
1142 close(rv);
1143 rv = 4;
1144 goto out;
1145 }
1146 tty_fd = rv;
1147 tty_devtty = is_devtty;
1148 rv = eno = 0;
1149 out:
1150 if (do_close)
1151 close(fd);
1152 errno = eno;
1153 return (rv);
1154 }
1155
1156 /* A shell error occurred (eg, syntax error, etc.) */
1157
1158 #define VWARNINGF_ERRORPREFIX 1
1159 #define VWARNINGF_FILELINE 2
1160 #define VWARNINGF_BUILTIN 4
1161 #define VWARNINGF_INTERNAL 8
1162
1163 static void vwarningf(unsigned int, const char *, va_list)
1164 MKSH_A_FORMAT(__printf__, 2, 0);
1165
1166 static void
vwarningf(unsigned int flags,const char * fmt,va_list ap)1167 vwarningf(unsigned int flags, const char *fmt, va_list ap)
1168 {
1169 if (fmt) {
1170 if (flags & VWARNINGF_INTERNAL)
1171 shf_fprintf(shl_out, "internal error: ");
1172 if (flags & VWARNINGF_ERRORPREFIX)
1173 error_prefix(tobool(flags & VWARNINGF_FILELINE));
1174 if ((flags & VWARNINGF_BUILTIN) &&
1175 /* not set when main() calls parse_args() */
1176 builtin_argv0 && builtin_argv0 != kshname)
1177 shf_fprintf(shl_out, "%s: ", builtin_argv0);
1178 shf_vfprintf(shl_out, fmt, ap);
1179 shf_putchar('\n', shl_out);
1180 }
1181 shf_flush(shl_out);
1182 }
1183
1184 void
errorfx(int rc,const char * fmt,...)1185 errorfx(int rc, const char *fmt, ...)
1186 {
1187 va_list va;
1188
1189 exstat = rc;
1190
1191 /* debugging: note that stdout not valid */
1192 shl_stdout_ok = false;
1193
1194 va_start(va, fmt);
1195 vwarningf(VWARNINGF_ERRORPREFIX | VWARNINGF_FILELINE, fmt, va);
1196 va_end(va);
1197 unwind(LERROR);
1198 }
1199
1200 void
errorf(const char * fmt,...)1201 errorf(const char *fmt, ...)
1202 {
1203 va_list va;
1204
1205 exstat = 1;
1206
1207 /* debugging: note that stdout not valid */
1208 shl_stdout_ok = false;
1209
1210 va_start(va, fmt);
1211 vwarningf(VWARNINGF_ERRORPREFIX | VWARNINGF_FILELINE, fmt, va);
1212 va_end(va);
1213 unwind(LERROR);
1214 }
1215
1216 /* like errorf(), but no unwind is done */
1217 void
warningf(bool fileline,const char * fmt,...)1218 warningf(bool fileline, const char *fmt, ...)
1219 {
1220 va_list va;
1221
1222 va_start(va, fmt);
1223 vwarningf(VWARNINGF_ERRORPREFIX | (fileline ? VWARNINGF_FILELINE : 0),
1224 fmt, va);
1225 va_end(va);
1226 }
1227
1228 /*
1229 * Used by built-in utilities to prefix shell and utility name to message
1230 * (also unwinds environments for special builtins).
1231 */
1232 void
bi_errorf(const char * fmt,...)1233 bi_errorf(const char *fmt, ...)
1234 {
1235 va_list va;
1236
1237 /* debugging: note that stdout not valid */
1238 shl_stdout_ok = false;
1239
1240 exstat = 1;
1241
1242 va_start(va, fmt);
1243 vwarningf(VWARNINGF_ERRORPREFIX | VWARNINGF_FILELINE |
1244 VWARNINGF_BUILTIN, fmt, va);
1245 va_end(va);
1246
1247 /*
1248 * POSIX special builtins and ksh special builtins cause
1249 * non-interactive shells to exit.
1250 * XXX odd use of KEEPASN; also may not want LERROR here
1251 */
1252 if (builtin_spec) {
1253 builtin_argv0 = NULL;
1254 unwind(LERROR);
1255 }
1256 }
1257
1258 /* Called when something that shouldn't happen does */
1259 void
internal_errorf(const char * fmt,...)1260 internal_errorf(const char *fmt, ...)
1261 {
1262 va_list va;
1263
1264 va_start(va, fmt);
1265 vwarningf(VWARNINGF_INTERNAL, fmt, va);
1266 va_end(va);
1267 unwind(LERROR);
1268 }
1269
1270 void
internal_warningf(const char * fmt,...)1271 internal_warningf(const char *fmt, ...)
1272 {
1273 va_list va;
1274
1275 va_start(va, fmt);
1276 vwarningf(VWARNINGF_INTERNAL, fmt, va);
1277 va_end(va);
1278 }
1279
1280 /* used by error reporting functions to print "ksh: .kshrc[25]: " */
1281 void
error_prefix(bool fileline)1282 error_prefix(bool fileline)
1283 {
1284 /* Avoid foo: foo[2]: ... */
1285 if (!fileline || !source || !source->file ||
1286 strcmp(source->file, kshname) != 0)
1287 shf_fprintf(shl_out, "%s: ", kshname + (*kshname == '-'));
1288 if (fileline && source && source->file != NULL) {
1289 shf_fprintf(shl_out, "%s[%lu]: ", source->file,
1290 (unsigned long)(source->errline ?
1291 source->errline : source->line));
1292 source->errline = 0;
1293 }
1294 }
1295
1296 /* printf to shl_out (stderr) with flush */
1297 void
shellf(const char * fmt,...)1298 shellf(const char *fmt, ...)
1299 {
1300 va_list va;
1301
1302 if (!initio_done)
1303 /* shl_out may not be set up yet... */
1304 return;
1305 va_start(va, fmt);
1306 shf_vfprintf(shl_out, fmt, va);
1307 va_end(va);
1308 shf_flush(shl_out);
1309 }
1310
1311 /* printf to shl_stdout (stdout) */
1312 void
shprintf(const char * fmt,...)1313 shprintf(const char *fmt, ...)
1314 {
1315 va_list va;
1316
1317 if (!shl_stdout_ok)
1318 internal_errorf("shl_stdout not valid");
1319 va_start(va, fmt);
1320 shf_vfprintf(shl_stdout, fmt, va);
1321 va_end(va);
1322 }
1323
1324 /* test if we can seek backwards fd (returns 0 or SHF_UNBUF) */
1325 int
can_seek(int fd)1326 can_seek(int fd)
1327 {
1328 struct stat statb;
1329
1330 return (fstat(fd, &statb) == 0 && !S_ISREG(statb.st_mode) ?
1331 SHF_UNBUF : 0);
1332 }
1333
1334 #ifdef DF
1335 int shl_dbg_fd;
1336 #define NSHF_IOB 4
1337 #else
1338 #define NSHF_IOB 3
1339 #endif
1340 struct shf shf_iob[NSHF_IOB];
1341
1342 void
initio(void)1343 initio(void)
1344 {
1345 #ifdef DF
1346 const char *lfp;
1347 #endif
1348
1349 /* force buffer allocation */
1350 shf_fdopen(1, SHF_WR, shl_stdout);
1351 shf_fdopen(2, SHF_WR, shl_out);
1352 shf_fdopen(2, SHF_WR, shl_xtrace);
1353 #ifdef DF
1354 if ((lfp = getenv("SDMKSH_PATH")) == NULL) {
1355 if ((lfp = getenv("HOME")) == NULL || *lfp != '/')
1356 errorf("cannot get home directory");
1357 lfp = shf_smprintf("%s/mksh-dbg.txt", lfp);
1358 }
1359
1360 if ((shl_dbg_fd = open(lfp, O_WRONLY | O_APPEND | O_CREAT, 0600)) < 0)
1361 errorf("cannot open debug output file %s", lfp);
1362 if (shl_dbg_fd < FDBASE) {
1363 int nfd;
1364
1365 nfd = fcntl(shl_dbg_fd, F_DUPFD, FDBASE);
1366 close(shl_dbg_fd);
1367 if ((shl_dbg_fd = nfd) == -1)
1368 errorf("cannot dup debug output file");
1369 }
1370 fcntl(shl_dbg_fd, F_SETFD, FD_CLOEXEC);
1371 shf_fdopen(shl_dbg_fd, SHF_WR, shl_dbg);
1372 DF("=== open ===");
1373 #endif
1374 initio_done = true;
1375 }
1376
1377 /* A dup2() with error checking */
1378 int
ksh_dup2(int ofd,int nfd,bool errok)1379 ksh_dup2(int ofd, int nfd, bool errok)
1380 {
1381 int rv;
1382
1383 if (((rv = dup2(ofd, nfd)) < 0) && !errok && (errno != EBADF))
1384 errorf("too many files open in shell");
1385
1386 #ifdef __ultrix
1387 /*XXX imake style */
1388 if (rv >= 0)
1389 fcntl(nfd, F_SETFD, 0);
1390 #endif
1391
1392 return (rv);
1393 }
1394
1395 /*
1396 * Move fd from user space (0 <= fd < 10) to shell space (fd >= 10),
1397 * set close-on-exec flag. See FDBASE in sh.h, maybe 24 not 10 here.
1398 */
1399 short
savefd(int fd)1400 savefd(int fd)
1401 {
1402 int nfd = fd;
1403
1404 if (fd < FDBASE && (nfd = fcntl(fd, F_DUPFD, FDBASE)) < 0 &&
1405 errno == EBADF)
1406 return (-1);
1407 if (nfd < 0 || nfd > SHRT_MAX)
1408 errorf("too many files open in shell");
1409 fcntl(nfd, F_SETFD, FD_CLOEXEC);
1410 return ((short)nfd);
1411 }
1412
1413 void
restfd(int fd,int ofd)1414 restfd(int fd, int ofd)
1415 {
1416 if (fd == 2)
1417 shf_flush(&shf_iob[/* fd */ 2]);
1418 if (ofd < 0)
1419 /* original fd closed */
1420 close(fd);
1421 else if (fd != ofd) {
1422 /*XXX: what to do if this dup fails? */
1423 ksh_dup2(ofd, fd, true);
1424 close(ofd);
1425 }
1426 }
1427
1428 void
openpipe(int * pv)1429 openpipe(int *pv)
1430 {
1431 int lpv[2];
1432
1433 if (pipe(lpv) < 0)
1434 errorf("can't create pipe - try again");
1435 pv[0] = savefd(lpv[0]);
1436 if (pv[0] != lpv[0])
1437 close(lpv[0]);
1438 pv[1] = savefd(lpv[1]);
1439 if (pv[1] != lpv[1])
1440 close(lpv[1]);
1441 }
1442
1443 void
closepipe(int * pv)1444 closepipe(int *pv)
1445 {
1446 close(pv[0]);
1447 close(pv[1]);
1448 }
1449
1450 /*
1451 * Called by iosetup() (deals with 2>&4, etc.), c_read, c_print to turn
1452 * a string (the X in 2>&X, read -uX, print -uX) into a file descriptor.
1453 */
1454 int
check_fd(const char * name,int mode,const char ** emsgp)1455 check_fd(const char *name, int mode, const char **emsgp)
1456 {
1457 int fd = 0, fl;
1458
1459 if (name[0] == 'p' && !name[1])
1460 return (coproc_getfd(mode, emsgp));
1461 while (ksh_isdigit(*name)) {
1462 fd = (fd * 10) + *name - '0';
1463 if (fd >= FDBASE) {
1464 if (emsgp)
1465 *emsgp = "file descriptor too large";
1466 return (-1);
1467 }
1468 ++name;
1469 }
1470 if (*name) {
1471 if (emsgp)
1472 *emsgp = "illegal file descriptor name";
1473 return (-1);
1474 }
1475 if ((fl = fcntl(fd, F_GETFL, 0)) < 0) {
1476 if (emsgp)
1477 *emsgp = "bad file descriptor";
1478 return (-1);
1479 }
1480 fl &= O_ACCMODE;
1481 /*
1482 * X_OK is a kludge to disable this check for dups (x<&1):
1483 * historical shells never did this check (XXX don't know what
1484 * POSIX has to say).
1485 */
1486 if (!(mode & X_OK) && fl != O_RDWR && (
1487 ((mode & R_OK) && fl != O_RDONLY) ||
1488 ((mode & W_OK) && fl != O_WRONLY))) {
1489 if (emsgp)
1490 *emsgp = (fl == O_WRONLY) ?
1491 "fd not open for reading" :
1492 "fd not open for writing";
1493 return (-1);
1494 }
1495 return (fd);
1496 }
1497
1498 /* Called once from main */
1499 void
coproc_init(void)1500 coproc_init(void)
1501 {
1502 coproc.read = coproc.readw = coproc.write = -1;
1503 coproc.njobs = 0;
1504 coproc.id = 0;
1505 }
1506
1507 /* Called by c_read() when eof is read - close fd if it is the co-process fd */
1508 void
coproc_read_close(int fd)1509 coproc_read_close(int fd)
1510 {
1511 if (coproc.read >= 0 && fd == coproc.read) {
1512 coproc_readw_close(fd);
1513 close(coproc.read);
1514 coproc.read = -1;
1515 }
1516 }
1517
1518 /*
1519 * Called by c_read() and by iosetup() to close the other side of the
1520 * read pipe, so reads will actually terminate.
1521 */
1522 void
coproc_readw_close(int fd)1523 coproc_readw_close(int fd)
1524 {
1525 if (coproc.readw >= 0 && coproc.read >= 0 && fd == coproc.read) {
1526 close(coproc.readw);
1527 coproc.readw = -1;
1528 }
1529 }
1530
1531 /*
1532 * Called by c_print when a write to a fd fails with EPIPE and by iosetup
1533 * when co-process input is dup'd
1534 */
1535 void
coproc_write_close(int fd)1536 coproc_write_close(int fd)
1537 {
1538 if (coproc.write >= 0 && fd == coproc.write) {
1539 close(coproc.write);
1540 coproc.write = -1;
1541 }
1542 }
1543
1544 /*
1545 * Called to check for existence of/value of the co-process file descriptor.
1546 * (Used by check_fd() and by c_read/c_print to deal with -p option).
1547 */
1548 int
coproc_getfd(int mode,const char ** emsgp)1549 coproc_getfd(int mode, const char **emsgp)
1550 {
1551 int fd = (mode & R_OK) ? coproc.read : coproc.write;
1552
1553 if (fd >= 0)
1554 return (fd);
1555 if (emsgp)
1556 *emsgp = "no coprocess";
1557 return (-1);
1558 }
1559
1560 /*
1561 * called to close file descriptors related to the coprocess (if any)
1562 * Should be called with SIGCHLD blocked.
1563 */
1564 void
coproc_cleanup(int reuse)1565 coproc_cleanup(int reuse)
1566 {
1567 /* This to allow co-processes to share output pipe */
1568 if (!reuse || coproc.readw < 0 || coproc.read < 0) {
1569 if (coproc.read >= 0) {
1570 close(coproc.read);
1571 coproc.read = -1;
1572 }
1573 if (coproc.readw >= 0) {
1574 close(coproc.readw);
1575 coproc.readw = -1;
1576 }
1577 }
1578 if (coproc.write >= 0) {
1579 close(coproc.write);
1580 coproc.write = -1;
1581 }
1582 }
1583
1584 struct temp *
maketemp(Area * ap,Temp_type type,struct temp ** tlist)1585 maketemp(Area *ap, Temp_type type, struct temp **tlist)
1586 {
1587 char *cp;
1588 size_t len;
1589 int i, j;
1590 struct temp *tp;
1591 const char *dir;
1592 struct stat sb;
1593
1594 dir = tmpdir ? tmpdir : MKSH_DEFAULT_TMPDIR;
1595 /* add "/shXXXXXX.tmp" plus NUL */
1596 len = strlen(dir);
1597 checkoktoadd(len, offsetof(struct temp, tffn[0]) + 14);
1598 tp = alloc(offsetof(struct temp, tffn[0]) + 14 + len, ap);
1599
1600 tp->shf = NULL;
1601 tp->pid = procpid;
1602 tp->type = type;
1603
1604 if (stat(dir, &sb) || !S_ISDIR(sb.st_mode)) {
1605 tp->tffn[0] = '\0';
1606 goto maketemp_out;
1607 }
1608
1609 cp = (void *)tp;
1610 cp += offsetof(struct temp, tffn[0]);
1611 memcpy(cp, dir, len);
1612 cp += len;
1613 memcpy(cp, "/shXXXXXX.tmp", 14);
1614 /* point to the first of six Xes */
1615 cp += 3;
1616 /* generate random part of filename */
1617 len = -1;
1618 do {
1619 i = rndget() % 36;
1620 cp[++len] = i < 26 ? 'a' + i : '0' + i - 26;
1621 } while (len < 5);
1622
1623 /* cyclically attempt to open a temporary file */
1624 while ((i = open(tp->tffn, O_CREAT | O_EXCL | O_RDWR | O_BINARY,
1625 0600)) < 0) {
1626 if (errno != EEXIST)
1627 goto maketemp_out;
1628 /* count down from z to a then from 9 to 0 */
1629 while (cp[len] == '0')
1630 if (!len--)
1631 goto maketemp_out;
1632 if (cp[len] == 'a')
1633 cp[len] = '9';
1634 else
1635 --cp[len];
1636 /* do another cycle */
1637 }
1638
1639 if (type == TT_FUNSUB) {
1640 /* map us high and mark as close-on-exec */
1641 if ((j = savefd(i)) != i) {
1642 close(i);
1643 i = j;
1644 }
1645
1646 /* operation mode for the shf */
1647 j = SHF_RD;
1648 } else
1649 j = SHF_WR;
1650
1651 /* shf_fdopen cannot fail, so no fd leak */
1652 tp->shf = shf_fdopen(i, j, NULL);
1653
1654 maketemp_out:
1655 tp->next = *tlist;
1656 *tlist = tp;
1657 return (tp);
1658 }
1659
1660 /*
1661 * We use a similar collision resolution algorithm as Python 2.5.4
1662 * but with a slightly tweaked implementation written from scratch.
1663 */
1664
1665 #define INIT_TBLSHIFT 3 /* initial table shift (2^3 = 8) */
1666 #define PERTURB_SHIFT 5 /* see Python 2.5.4 Objects/dictobject.c */
1667
1668 static void tgrow(struct table *);
1669 static int tnamecmp(const void *, const void *);
1670
1671 static void
tgrow(struct table * tp)1672 tgrow(struct table *tp)
1673 {
1674 size_t i, j, osize, mask, perturb;
1675 struct tbl *tblp, **pp;
1676 struct tbl **ntblp, **otblp = tp->tbls;
1677
1678 if (tp->tshift > 29)
1679 internal_errorf("hash table size limit reached");
1680
1681 /* calculate old size, new shift and new size */
1682 osize = (size_t)1 << (tp->tshift++);
1683 i = osize << 1;
1684
1685 ntblp = alloc2(i, sizeof(struct tbl *), tp->areap);
1686 /* multiplication cannot overflow: alloc2 checked that */
1687 memset(ntblp, 0, i * sizeof(struct tbl *));
1688
1689 /* table can get very full when reaching its size limit */
1690 tp->nfree = (tp->tshift == 30) ? 0x3FFF0000UL :
1691 /* but otherwise, only 75% */
1692 ((i * 3) / 4);
1693 tp->tbls = ntblp;
1694 if (otblp == NULL)
1695 return;
1696
1697 mask = i - 1;
1698 for (i = 0; i < osize; i++)
1699 if ((tblp = otblp[i]) != NULL) {
1700 if ((tblp->flag & DEFINED)) {
1701 /* search for free hash table slot */
1702 j = perturb = tblp->ua.hval;
1703 goto find_first_empty_slot;
1704 find_next_empty_slot:
1705 j = (j << 2) + j + perturb + 1;
1706 perturb >>= PERTURB_SHIFT;
1707 find_first_empty_slot:
1708 pp = &ntblp[j & mask];
1709 if (*pp != NULL)
1710 goto find_next_empty_slot;
1711 /* found an empty hash table slot */
1712 *pp = tblp;
1713 tp->nfree--;
1714 } else if (!(tblp->flag & FINUSE)) {
1715 afree(tblp, tp->areap);
1716 }
1717 }
1718 afree(otblp, tp->areap);
1719 }
1720
1721 void
ktinit(Area * ap,struct table * tp,uint8_t initshift)1722 ktinit(Area *ap, struct table *tp, uint8_t initshift)
1723 {
1724 tp->areap = ap;
1725 tp->tbls = NULL;
1726 tp->tshift = ((initshift > INIT_TBLSHIFT) ?
1727 initshift : INIT_TBLSHIFT) - 1;
1728 tgrow(tp);
1729 }
1730
1731 /* table, name (key) to search for, hash(name), rv pointer to tbl ptr */
1732 struct tbl *
ktscan(struct table * tp,const char * name,uint32_t h,struct tbl *** ppp)1733 ktscan(struct table *tp, const char *name, uint32_t h, struct tbl ***ppp)
1734 {
1735 size_t j, perturb, mask;
1736 struct tbl **pp, *p;
1737
1738 mask = ((size_t)1 << (tp->tshift)) - 1;
1739 /* search for hash table slot matching name */
1740 j = perturb = h;
1741 goto find_first_slot;
1742 find_next_slot:
1743 j = (j << 2) + j + perturb + 1;
1744 perturb >>= PERTURB_SHIFT;
1745 find_first_slot:
1746 pp = &tp->tbls[j & mask];
1747 if ((p = *pp) != NULL && (p->ua.hval != h || !(p->flag & DEFINED) ||
1748 strcmp(p->name, name)))
1749 goto find_next_slot;
1750 /* p == NULL if not found, correct found entry otherwise */
1751 if (ppp)
1752 *ppp = pp;
1753 return (p);
1754 }
1755
1756 /* table, name (key) to enter, hash(n) */
1757 struct tbl *
ktenter(struct table * tp,const char * n,uint32_t h)1758 ktenter(struct table *tp, const char *n, uint32_t h)
1759 {
1760 struct tbl **pp, *p;
1761 size_t len;
1762
1763 Search:
1764 if ((p = ktscan(tp, n, h, &pp)))
1765 return (p);
1766
1767 if (tp->nfree == 0) {
1768 /* too full */
1769 tgrow(tp);
1770 goto Search;
1771 }
1772
1773 /* create new tbl entry */
1774 len = strlen(n);
1775 checkoktoadd(len, offsetof(struct tbl, name[0]) + 1);
1776 p = alloc(offsetof(struct tbl, name[0]) + ++len, tp->areap);
1777 p->flag = 0;
1778 p->type = 0;
1779 p->areap = tp->areap;
1780 p->ua.hval = h;
1781 p->u2.field = 0;
1782 p->u.array = NULL;
1783 memcpy(p->name, n, len);
1784
1785 /* enter in tp->tbls */
1786 tp->nfree--;
1787 *pp = p;
1788 return (p);
1789 }
1790
1791 void
ktwalk(struct tstate * ts,struct table * tp)1792 ktwalk(struct tstate *ts, struct table *tp)
1793 {
1794 ts->left = (size_t)1 << (tp->tshift);
1795 ts->next = tp->tbls;
1796 }
1797
1798 struct tbl *
ktnext(struct tstate * ts)1799 ktnext(struct tstate *ts)
1800 {
1801 while (--ts->left >= 0) {
1802 struct tbl *p = *ts->next++;
1803 if (p != NULL && (p->flag & DEFINED))
1804 return (p);
1805 }
1806 return (NULL);
1807 }
1808
1809 static int
tnamecmp(const void * p1,const void * p2)1810 tnamecmp(const void *p1, const void *p2)
1811 {
1812 const struct tbl *a = *((const struct tbl * const *)p1);
1813 const struct tbl *b = *((const struct tbl * const *)p2);
1814
1815 return (strcmp(a->name, b->name));
1816 }
1817
1818 struct tbl **
ktsort(struct table * tp)1819 ktsort(struct table *tp)
1820 {
1821 size_t i;
1822 struct tbl **p, **sp, **dp;
1823
1824 /*
1825 * since the table is never entirely full, no need to reserve
1826 * additional space for the trailing NULL appended below
1827 */
1828 i = (size_t)1 << (tp->tshift);
1829 p = alloc2(i, sizeof(struct tbl *), ATEMP);
1830 sp = tp->tbls; /* source */
1831 dp = p; /* dest */
1832 while (i--)
1833 if ((*dp = *sp++) != NULL && (((*dp)->flag & DEFINED) ||
1834 ((*dp)->flag & ARRAY)))
1835 dp++;
1836 qsort(p, (i = dp - p), sizeof(struct tbl *), tnamecmp);
1837 p[i] = NULL;
1838 return (p);
1839 }
1840
1841 #ifdef SIGWINCH
1842 static void
x_sigwinch(int sig MKSH_A_UNUSED)1843 x_sigwinch(int sig MKSH_A_UNUSED)
1844 {
1845 /* this runs inside interrupt context, with errno saved */
1846
1847 got_winch = 1;
1848 }
1849 #endif
1850
1851 #ifdef DF
1852 void
DF(const char * fmt,...)1853 DF(const char *fmt, ...)
1854 {
1855 va_list args;
1856 struct timeval tv;
1857 mirtime_mjd mjd;
1858
1859 mksh_lockfd(shl_dbg_fd);
1860 mksh_TIME(tv);
1861 timet2mjd(&mjd, tv.tv_sec);
1862 shf_fprintf(shl_dbg, "[%02u:%02u:%02u (%u) %u.%06u] ",
1863 (unsigned)mjd.sec / 3600, ((unsigned)mjd.sec / 60) % 60,
1864 (unsigned)mjd.sec % 60, (unsigned)getpid(),
1865 (unsigned)tv.tv_sec, (unsigned)tv.tv_usec);
1866 va_start(args, fmt);
1867 shf_vfprintf(shl_dbg, fmt, args);
1868 va_end(args);
1869 shf_putc('\n', shl_dbg);
1870 shf_flush(shl_dbg);
1871 mksh_unlkfd(shl_dbg_fd);
1872 }
1873 #endif
1874
1875 void
x_mkraw(int fd,mksh_ttyst * ocb,bool forread)1876 x_mkraw(int fd, mksh_ttyst *ocb, bool forread)
1877 {
1878 mksh_ttyst cb;
1879
1880 if (ocb)
1881 mksh_tcget(fd, ocb);
1882 else
1883 ocb = &tty_state;
1884
1885 cb = *ocb;
1886 if (forread) {
1887 cb.c_iflag &= ~(ISTRIP);
1888 cb.c_lflag &= ~(ICANON) | ECHO;
1889 } else {
1890 cb.c_iflag &= ~(INLCR | ICRNL | ISTRIP);
1891 cb.c_lflag &= ~(ISIG | ICANON | ECHO);
1892 }
1893 #if defined(VLNEXT) && defined(_POSIX_VDISABLE)
1894 /* OSF/1 processes lnext when ~icanon */
1895 cb.c_cc[VLNEXT] = _POSIX_VDISABLE;
1896 #endif
1897 /* SunOS 4.1.x & OSF/1 processes discard(flush) when ~icanon */
1898 #if defined(VDISCARD) && defined(_POSIX_VDISABLE)
1899 cb.c_cc[VDISCARD] = _POSIX_VDISABLE;
1900 #endif
1901 cb.c_cc[VTIME] = 0;
1902 cb.c_cc[VMIN] = 1;
1903
1904 mksh_tcset(fd, &cb);
1905 }
1906