/* $OpenBSD: main.c,v 1.52 2013/06/15 17:25:19 millert Exp $ */ /* $OpenBSD: tty.c,v 1.9 2006/03/14 22:08:01 deraadt Exp $ */ /* $OpenBSD: io.c,v 1.22 2006/03/17 16:30:13 millert Exp $ */ /* $OpenBSD: table.c,v 1.15 2012/02/19 07:52:30 otto Exp $ */ /*- * Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, * 2011, 2012, 2013 * Thorsten Glaser <tg@mirbsd.org> * * Provided that these terms and disclaimer and all copyright notices * are retained or reproduced in an accompanying document, permission * is granted to deal in this work without restriction, including un- * limited rights to use, publicly perform, distribute, sell, modify, * merge, give away, or sublicence. * * This work is provided "AS IS" and WITHOUT WARRANTY of any kind, to * the utmost extent permitted by applicable law, neither express nor * implied; without malicious intent or gross negligence. In no event * may a licensor, author or contributor be held liable for indirect, * direct, other damage, loss, or other issues arising in any way out * of dealing in the work, even if advised of the possibility of such * damage or existence of a defect, except proven that it results out * of said person's immediate fault when using the work as intended. */ #define EXTERN #include "sh.h" #if HAVE_LANGINFO_CODESET #include <langinfo.h> #endif #if HAVE_SETLOCALE_CTYPE #include <locale.h> #endif __RCSID("$MirOS: src/bin/mksh/main.c,v 1.269 2013/07/25 18:07:46 tg Exp $"); extern char **environ; #ifndef MKSHRC_PATH #define MKSHRC_PATH "~/.mkshrc" #endif #ifndef MKSH_DEFAULT_TMPDIR #define MKSH_DEFAULT_TMPDIR "/tmp" #endif static uint8_t isuc(const char *); static int main_init(int, const char *[], Source **, struct block **); uint32_t chvt_rndsetup(const void *, size_t); void chvt_reinit(void); static void reclaim(void); static void remove_temps(struct temp *); static mksh_uari_t rndsetup(void); #ifdef SIGWINCH static void x_sigwinch(int); #endif static const char initifs[] = "IFS= \t\n"; static const char initsubs[] = "${PS2=> } ${PS3=#? } ${PS4=+ } ${SECONDS=0} ${TMOUT=0} ${EPOCHREALTIME=}"; static const char *initcoms[] = { Ttypeset, "-r", initvsn, NULL, Ttypeset, "-x", "HOME", "PATH", "RANDOM", "SHELL", NULL, Ttypeset, "-i10", "COLUMNS", "LINES", "SECONDS", "TMOUT", NULL, Talias, "integer=typeset -i", Tlocal_typeset, /* not "alias -t --": hash -r needs to work */ "hash=alias -t", "type=whence -v", #if !defined(ANDROID) && !defined(MKSH_UNEMPLOYED) /* not in Android for political reasons */ /* not in ARGE mksh due to no job control */ "stop=kill -STOP", "suspend=kill -STOP $$", #endif "autoload=typeset -fu", "functions=typeset -f", "history=fc -l", "nameref=typeset -n", "nohup=nohup ", Tr_fc_e_dash, "source=PATH=$PATH:. command .", "login=exec login", NULL, /* this is what AT&T ksh seems to track, with the addition of emacs */ Talias, "-tU", "cat", "cc", "chmod", "cp", "date", "ed", "emacs", "grep", "ls", "make", "mv", "pr", "rm", "sed", "sh", "vi", "who", NULL, NULL }; static const char *restr_com[] = { Ttypeset, "-r", "PATH", "ENV", "SHELL", NULL }; static bool initio_done; /* top-level parsing and execution environment */ static struct env env; struct env *e = &env; static mksh_uari_t rndsetup(void) { register uint32_t h; struct { ALLOC_ITEM alloc_INT; void *dataptr, *stkptr, *mallocptr; #if defined(__GLIBC__) && (__GLIBC__ >= 2) sigjmp_buf jbuf; #endif struct timeval tv; } *bufptr; char *cp; cp = alloc(sizeof(*bufptr) - ALLOC_SIZE, APERM); #ifdef DEBUG /* clear the allocated space, for valgrind */ memset(cp, 0, sizeof(*bufptr) - ALLOC_SIZE); #endif /* undo what alloc() did to the malloc result address */ bufptr = (void *)(cp - ALLOC_SIZE); /* PIE or something similar provides us with deltas here */ bufptr->dataptr = &rndsetupstate; /* ASLR in at least Windows, Linux, some BSDs */ bufptr->stkptr = &bufptr; /* randomised malloc in BSD (and possibly others) */ bufptr->mallocptr = bufptr; #if defined(__GLIBC__) && (__GLIBC__ >= 2) /* glibc pointer guard */ sigsetjmp(bufptr->jbuf, 1); #endif /* introduce variation (and yes, second arg MBZ for portability) */ mksh_TIME(bufptr->tv); h = chvt_rndsetup(bufptr, sizeof(*bufptr)); afree(cp, APERM); return ((mksh_uari_t)h); } uint32_t chvt_rndsetup(const void *bp, size_t sz) { register uint32_t h; NZATInit(h); /* variation through pid, ppid, and the works */ NZATUpdateMem(h, &rndsetupstate, sizeof(rndsetupstate)); /* some variation, some possibly entropy, depending on OE */ NZATUpdateMem(h, bp, sz); NZAATFinish(h); return (h); } void chvt_reinit(void) { kshpid = procpid = getpid(); ksheuid = geteuid(); kshpgrp = getpgrp(); kshppid = getppid(); } static const char *empty_argv[] = { "mksh", NULL }; static uint8_t isuc(const char *cx) { char *cp, *x; uint8_t rv = 0; if (!cx || !*cx) return (0); /* uppercase a string duplicate */ strdupx(x, cx, ATEMP); cp = x; while ((*cp = ksh_toupper(*cp))) ++cp; /* check for UTF-8 */ if (strstr(x, "UTF-8") || strstr(x, "UTF8")) rv = 1; /* free copy and out */ afree(x, ATEMP); return (rv); } static int main_init(int argc, const char *argv[], Source **sp, struct block **lp) { int argi, i; Source *s = NULL; struct block *l; unsigned char restricted, errexit, utf_flag; char *cp; const char *ccp, **wp; struct tbl *vp; struct stat s_stdin; #if !defined(_PATH_DEFPATH) && defined(_CS_PATH) ssize_t k; #endif /* do things like getpgrp() et al. */ chvt_reinit(); /* make sure argv[] is sane */ if (!*argv) { argv = empty_argv; argc = 1; } kshname = argv[0]; /* initialise permanent Area */ ainit(&aperm); /* set up base environment */ env.type = E_NONE; ainit(&env.area); /* set up global l->vars and l->funs */ newblock(); /* Do this first so output routines (eg, errorf, shellf) can work */ initio(); /* determine the basename (without '-' or path) of the executable */ ccp = kshname; goto begin_parse_kshname; while ((i = ccp[argi++])) { if (i == '/') { ccp += argi; begin_parse_kshname: argi = 0; if (*ccp == '-') ++ccp; } } if (!*ccp) ccp = empty_argv[0]; /* define built-in commands and see if we were called as one */ ktinit(APERM, &builtins, /* currently up to 51 builtins: 75% of 128 = 2^7 */ 7); for (i = 0; mkshbuiltins[i].name != NULL; i++) if (!strcmp(ccp, builtin(mkshbuiltins[i].name, mkshbuiltins[i].func))) Flag(FAS_BUILTIN) = 1; if (!Flag(FAS_BUILTIN)) { /* check for -T option early */ argi = parse_args(argv, OF_FIRSTTIME, NULL); if (argi < 0) return (1); #if defined(MKSH_BINSHPOSIX) || defined(MKSH_BINSHREDUCED) /* are we called as -sh or /bin/sh or so? */ if (!strcmp(ccp, "sh")) { /* either also turns off braceexpand */ #ifdef MKSH_BINSHPOSIX /* enable better POSIX conformance */ change_flag(FPOSIX, OF_FIRSTTIME, true); #endif #ifdef MKSH_BINSHREDUCED /* enable kludge/compat mode */ change_flag(FSH, OF_FIRSTTIME, true); #endif } #endif } initvar(); initctypes(); inittraps(); coproc_init(); /* set up variable and command dictionaries */ ktinit(APERM, &taliases, 0); ktinit(APERM, &aliases, 0); #ifndef MKSH_NOPWNAM ktinit(APERM, &homedirs, 0); #endif /* define shell keywords */ initkeywords(); init_histvec(); /* initialise tty size before importing environment */ change_winsz(); #ifdef _PATH_DEFPATH def_path = _PATH_DEFPATH; #else #ifdef _CS_PATH if ((k = confstr(_CS_PATH, NULL, 0)) > 0 && confstr(_CS_PATH, cp = alloc(k + 1, APERM), k + 1) == k + 1) def_path = cp; else #endif /* * this is uniform across all OSes unless it * breaks somewhere; don't try to optimise, * e.g. add stuff for Interix or remove /usr * for HURD, because e.g. Debian GNU/HURD is * "keeping a regular /usr"; this is supposed * to be a sane 'basic' default PATH */ def_path = "/bin:/usr/bin:/sbin:/usr/sbin"; #endif /* * Set PATH to def_path (will set the path global variable). * (import of environment below will probably change this setting). */ vp = global("PATH"); /* setstr can't fail here */ setstr(vp, def_path, KSH_RETURN_ERROR); /* * Turn on nohup by default for now - will change to off * by default once people are aware of its existence * (AT&T ksh does not have a nohup option - it always sends * the hup). */ Flag(FNOHUP) = 1; /* * Turn on brace expansion by default. AT&T kshs that have * alternation always have it on. */ Flag(FBRACEEXPAND) = 1; /* * Turn on "set -x" inheritance by default. */ Flag(FXTRACEREC) = 1; #ifndef MKSH_NO_CMDLINE_EDITING /* * Set edit mode to emacs by default, may be overridden * by the environment or the user. Also, we want tab completion * on in vi by default. */ change_flag(FEMACS, OF_SPECIAL, true); #if !MKSH_S_NOVI Flag(FVITABCOMPLETE) = 1; #endif #endif /* import environment */ if (environ != NULL) for (wp = (const char **)environ; *wp != NULL; wp++) typeset(*wp, IMPORT | EXPORT, 0, 0, 0); /* for security */ typeset(initifs, 0, 0, 0, 0); /* assign default shell variable values */ substitute(initsubs, 0); /* Figure out the current working directory and set $PWD */ vp = global("PWD"); cp = str_val(vp); /* Try to use existing $PWD if it is valid */ set_current_wd((cp[0] == '/' && test_eval(NULL, TO_FILEQ, cp, ".", true)) ? cp : NULL); if (current_wd[0]) simplify_path(current_wd); /* Only set pwd if we know where we are or if it had a bogus value */ if (current_wd[0] || *cp) /* setstr can't fail here */ setstr(vp, current_wd, KSH_RETURN_ERROR); for (wp = initcoms; *wp != NULL; wp++) { shcomexec(wp); while (*wp != NULL) wp++; } setint_n(global("OPTIND"), 1, 10); kshuid = getuid(); kshgid = getgid(); kshegid = getegid(); safe_prompt = ksheuid ? "$ " : "# "; vp = global("PS1"); /* Set PS1 if unset or we are root and prompt doesn't contain a # */ if (!(vp->flag & ISSET) || (!ksheuid && !strchr(str_val(vp), '#'))) /* setstr can't fail here */ setstr(vp, safe_prompt, KSH_RETURN_ERROR); setint_n((vp = global("BASHPID")), 0, 10); vp->flag |= INT_U; setint_n((vp = global("PGRP")), (mksh_uari_t)kshpgrp, 10); vp->flag |= INT_U; setint_n((vp = global("PPID")), (mksh_uari_t)kshppid, 10); vp->flag |= INT_U; setint_n((vp = global("USER_ID")), (mksh_uari_t)ksheuid, 10); vp->flag |= INT_U; setint_n((vp = global("KSHUID")), (mksh_uari_t)kshuid, 10); vp->flag |= INT_U; setint_n((vp = global("KSHEGID")), (mksh_uari_t)kshegid, 10); vp->flag |= INT_U; setint_n((vp = global("KSHGID")), (mksh_uari_t)kshgid, 10); vp->flag |= INT_U; setint_n((vp = global("RANDOM")), rndsetup(), 10); vp->flag |= INT_U; setint_n((vp_pipest = global("PIPESTATUS")), 0, 10); /* Set this before parsing arguments */ Flag(FPRIVILEGED) = kshuid != ksheuid || kshgid != kshegid; /* this to note if monitor is set on command line (see below) */ #ifndef MKSH_UNEMPLOYED Flag(FMONITOR) = 127; #endif /* this to note if utf-8 mode is set on command line (see below) */ UTFMODE = 2; if (!Flag(FAS_BUILTIN)) { argi = parse_args(argv, OF_CMDLINE, NULL); if (argi < 0) return (1); } #if defined(DEBUG) && !defined(MKSH_LEGACY_MODE) /* test wraparound of arithmetic types */ { volatile long xl; volatile unsigned long xul; volatile int xi; volatile unsigned int xui; volatile mksh_ari_t xa; volatile mksh_uari_t xua, xua2; volatile uint8_t xc; xa = 2147483647; xua = 2147483647; ++xa; ++xua; xua2 = xa; xl = xa; xul = xua; xa = 0; xua = 0; --xa; --xua; xi = xa; xui = xua; xa = -1; xua = xa; ++xa; ++xua; xc = 0; --xc; if ((xua2 != 2147483648UL) || (xl != (-2147483647L-1)) || (xul != 2147483648UL) || (xi != -1) || (xui != 4294967295U) || (xa != 0) || (xua != 0) || (xc != 255)) errorf("integer wraparound test failed"); } #endif /* process this later only, default to off (hysterical raisins) */ utf_flag = UTFMODE; UTFMODE = 0; if (Flag(FAS_BUILTIN)) { /* auto-detect from environment variables, always */ utf_flag = 3; } else if (Flag(FCOMMAND)) { s = pushs(SSTRINGCMDLINE, ATEMP); if (!(s->start = s->str = argv[argi++])) errorf("%s %s", "-c", "requires an argument"); #if !defined(MKSH_SMALL) while (*s->str) { if (*s->str != ' ' && ctype(*s->str, C_QUOTE)) break; s->str++; } if (!*s->str) s->flags |= SF_MAYEXEC; s->str = s->start; #endif #ifdef MKSH_MIDNIGHTBSD01ASH_COMPAT /* compatibility to MidnightBSD 0.1 /bin/sh (kludge) */ if (Flag(FSH) && argv[argi] && !strcmp(argv[argi], "--")) ++argi; #endif if (argv[argi]) kshname = argv[argi++]; } else if (argi < argc && !Flag(FSTDIN)) { s = pushs(SFILE, ATEMP); s->file = argv[argi++]; s->u.shf = shf_open(s->file, O_RDONLY, 0, SHF_MAPHI | SHF_CLEXEC); if (s->u.shf == NULL) { shl_stdout_ok = false; warningf(true, "%s: %s", s->file, cstrerror(errno)); /* mandated by SUSv4 */ exstat = 127; unwind(LERROR); } kshname = s->file; } else { Flag(FSTDIN) = 1; s = pushs(SSTDIN, ATEMP); s->file = "<stdin>"; s->u.shf = shf_fdopen(0, SHF_RD | can_seek(0), NULL); if (isatty(0) && isatty(2)) { Flag(FTALKING) = Flag(FTALKING_I) = 1; /* The following only if isatty(0) */ s->flags |= SF_TTY; s->u.shf->flags |= SHF_INTERRUPT; s->file = NULL; } } /* this bizarreness is mandated by POSIX */ if (fstat(0, &s_stdin) >= 0 && S_ISCHR(s_stdin.st_mode) && Flag(FTALKING)) reset_nonblock(0); /* initialise job control */ j_init(); /* do this after j_init() which calls tty_init_state() */ if (Flag(FTALKING)) { if (utf_flag == 2) { #ifndef MKSH_ASSUME_UTF8 /* auto-detect from locale or environment */ utf_flag = 4; #elif MKSH_ASSUME_UTF8 utf_flag = 1; #else /* always disable UTF-8 (for interactive) */ utf_flag = 0; #endif } #ifndef MKSH_NO_CMDLINE_EDITING x_init(); #endif } #ifdef SIGWINCH sigtraps[SIGWINCH].flags |= TF_SHELL_USES; setsig(&sigtraps[SIGWINCH], x_sigwinch, SS_RESTORE_ORIG|SS_FORCE|SS_SHTRAP); #endif l = e->loc; if (Flag(FAS_BUILTIN)) { l->argc = argc; l->argv = argv; l->argv[0] = ccp; } else { l->argc = argc - argi; /* * allocate a new array because otherwise, when we modify * it in-place, ps(1) output changes; the meaning of argc * here is slightly different as it excludes kshname, and * we add a trailing NULL sentinel as well */ l->argv = alloc2(l->argc + 2, sizeof(void *), APERM); l->argv[0] = kshname; memcpy(&l->argv[1], &argv[argi], l->argc * sizeof(void *)); l->argv[l->argc + 1] = NULL; getopts_reset(1); } /* divine the initial state of the utf8-mode Flag */ ccp = null; switch (utf_flag) { /* auto-detect from locale or environment */ case 4: #if HAVE_SETLOCALE_CTYPE ccp = setlocale(LC_CTYPE, ""); #if HAVE_LANGINFO_CODESET if (!isuc(ccp)) ccp = nl_langinfo(CODESET); #endif if (!isuc(ccp)) ccp = null; /* FALLTHROUGH */ #endif /* auto-detect from environment */ case 3: /* these were imported from environ earlier */ if (ccp == null) ccp = str_val(global("LC_ALL")); if (ccp == null) ccp = str_val(global("LC_CTYPE")); if (ccp == null) ccp = str_val(global("LANG")); UTFMODE = isuc(ccp); break; /* not set on command line, not FTALKING */ case 2: /* unknown values */ default: utf_flag = 0; /* FALLTHROUGH */ /* known values */ case 1: case 0: UTFMODE = utf_flag; break; } /* Disable during .profile/ENV reading */ restricted = Flag(FRESTRICTED); Flag(FRESTRICTED) = 0; errexit = Flag(FERREXIT); Flag(FERREXIT) = 0; /* * Do this before profile/$ENV so that if it causes problems in them, * user will know why things broke. */ if (!current_wd[0] && Flag(FTALKING)) warningf(false, "can't determine current directory"); if (Flag(FLOGIN)) { include(MKSH_SYSTEM_PROFILE, 0, NULL, true); if (!Flag(FPRIVILEGED)) include(substitute("$HOME/.profile", 0), 0, NULL, true); } if (Flag(FPRIVILEGED)) include(MKSH_SUID_PROFILE, 0, NULL, true); else if (Flag(FTALKING)) { char *env_file; /* include $ENV */ env_file = substitute(substitute("${ENV:-" MKSHRC_PATH "}", 0), DOTILDE); if (*env_file != '\0') include(env_file, 0, NULL, true); } if (restricted) { shcomexec(restr_com); /* After typeset command... */ Flag(FRESTRICTED) = 1; } Flag(FERREXIT) = errexit; if (Flag(FTALKING) && s) hist_init(s); else /* set after ENV */ Flag(FTRACKALL) = 1; alarm_init(); *sp = s; *lp = l; return (0); } /* this indirection barrier reduces stack usage during normal operation */ int main(int argc, const char *argv[]) { int rv; Source *s; struct block *l; if ((rv = main_init(argc, argv, &s, &l)) == 0) { if (Flag(FAS_BUILTIN)) { rv = shcomexec(l->argv); } else { shell(s, true); /* NOTREACHED */ } } return (rv); } int include(const char *name, int argc, const char **argv, bool intr_ok) { Source *volatile s = NULL; struct shf *shf; const char **volatile old_argv; volatile int old_argc; int i; shf = shf_open(name, O_RDONLY, 0, SHF_MAPHI | SHF_CLEXEC); if (shf == NULL) return (-1); if (argv) { old_argv = e->loc->argv; old_argc = e->loc->argc; } else { old_argv = NULL; old_argc = 0; } newenv(E_INCL); if ((i = kshsetjmp(e->jbuf))) { quitenv(s ? s->u.shf : NULL); if (old_argv) { e->loc->argv = old_argv; e->loc->argc = old_argc; } switch (i) { case LRETURN: case LERROR: /* see below */ return (exstat & 0xFF); case LINTR: /* * intr_ok is set if we are including .profile or $ENV. * If user ^Cs out, we don't want to kill the shell... */ if (intr_ok && ((exstat & 0xFF) - 128) != SIGTERM) return (1); /* FALLTHROUGH */ case LEXIT: case LLEAVE: case LSHELL: unwind(i); /* NOTREACHED */ default: internal_errorf("%s %d", "include", i); /* NOTREACHED */ } } if (argv) { e->loc->argv = argv; e->loc->argc = argc; } s = pushs(SFILE, ATEMP); s->u.shf = shf; strdupx(s->file, name, ATEMP); i = shell(s, false); quitenv(s->u.shf); if (old_argv) { e->loc->argv = old_argv; e->loc->argc = old_argc; } /* & 0xff to ensure value not -1 */ return (i & 0xFF); } /* spawn a command into a shell optionally keeping track of the line number */ int command(const char *comm, int line) { Source *s; s = pushs(SSTRING, ATEMP); s->start = s->str = comm; s->line = line; return (shell(s, false)); } /* * run the commands from the input source, returning status. */ int shell(Source * volatile s, volatile bool toplevel) { struct op *t; volatile bool wastty = tobool(s->flags & SF_TTY); volatile uint8_t attempts = 13; volatile bool interactive = Flag(FTALKING) && toplevel; volatile bool sfirst = true; Source *volatile old_source = source; int i; newenv(E_PARSE); if (interactive) really_exit = false; switch ((i = kshsetjmp(e->jbuf))) { case 0: break; case LINTR: /* we get here if SIGINT not caught or ignored */ case LERROR: case LSHELL: if (interactive) { if (i == LINTR) shellf("\n"); /* * Reset any eof that was read as part of a * multiline command. */ if (Flag(FIGNOREEOF) && s->type == SEOF && wastty) s->type = SSTDIN; /* * Used by exit command to get back to * top level shell. Kind of strange since * interactive is set if we are reading from * a tty, but to have stopped jobs, one only * needs FMONITOR set (not FTALKING/SF_TTY)... */ /* toss any input we have so far */ yyrecursive_pop(true); s->start = s->str = null; retrace_info = NULL; herep = heres; break; } /* FALLTHROUGH */ case LEXIT: case LLEAVE: case LRETURN: source = old_source; quitenv(NULL); /* keep on going */ unwind(i); /* NOTREACHED */ default: source = old_source; quitenv(NULL); internal_errorf("%s %d", "shell", i); /* NOTREACHED */ } while (/* CONSTCOND */ 1) { if (trap) runtraps(0); if (s->next == NULL) { if (Flag(FVERBOSE)) s->flags |= SF_ECHO; else s->flags &= ~SF_ECHO; } if (interactive) { j_notify(); set_prompt(PS1, s); } t = compile(s, sfirst); sfirst = false; if (!t) goto source_no_tree; if (t->type == TEOF) { if (wastty && Flag(FIGNOREEOF) && --attempts > 0) { shellf("Use 'exit' to leave mksh\n"); s->type = SSTDIN; } else if (wastty && !really_exit && j_stopped_running()) { really_exit = true; s->type = SSTDIN; } else { /* * this for POSIX which says EXIT traps * shall be taken in the environment * immediately after the last command * executed. */ if (toplevel) unwind(LEXIT); break; } } #if !defined(MKSH_SMALL) else if ((s->flags & SF_MAYEXEC) && t->type == TCOM) t->u.evalflags |= DOTCOMEXEC; #endif if (!Flag(FNOEXEC) || (s->flags & SF_TTY)) exstat = execute(t, 0, NULL) & 0xFF; if (t->type != TEOF && interactive && really_exit) really_exit = false; source_no_tree: reclaim(); } quitenv(NULL); source = old_source; return (exstat & 0xFF); } /* return to closest error handler or shell(), exit if none found */ /* note: i MUST NOT be 0 */ void unwind(int i) { /* * This is a kludge. We need to restore everything that was * changed in the new environment, see cid 1005090337C7A669439 * and 10050903386452ACBF1, but fail to even save things most of * the time. funcs.c:c_eval() changes FERREXIT temporarily to 0, * which needs to be restored thus (related to Debian #696823). * We did not save the shell flags, so we use a special or'd * value here... this is mostly to clean up behind *other* * callers of unwind(LERROR) here; exec.c has the regular case. */ if (Flag(FERREXIT) & 0x80) { /* GNU bash does not run this trapsig */ trapsig(ksh_SIGERR); Flag(FERREXIT) &= ~0x80; } /* ordering for EXIT vs ERR is a bit odd (this is what AT&T ksh does) */ if (i == LEXIT || ((i == LERROR || i == LINTR) && sigtraps[ksh_SIGEXIT].trap && (!Flag(FTALKING) || Flag(FERREXIT)))) { ++trap_nested; runtrap(&sigtraps[ksh_SIGEXIT], trap_nested == 1); --trap_nested; i = LLEAVE; } else if (Flag(FERREXIT) == 1 && (i == LERROR || i == LINTR)) { ++trap_nested; runtrap(&sigtraps[ksh_SIGERR], trap_nested == 1); --trap_nested; i = LLEAVE; } while (/* CONSTCOND */ 1) { switch (e->type) { case E_PARSE: case E_FUNC: case E_INCL: case E_LOOP: case E_ERRH: kshlongjmp(e->jbuf, i); /* NOTREACHED */ case E_NONE: if (i == LINTR) e->flags |= EF_FAKE_SIGDIE; /* FALLTHROUGH */ default: quitenv(NULL); } } } void newenv(int type) { struct env *ep; char *cp; /* * struct env includes ALLOC_ITEM for alignment constraints * so first get the actually used memory, then assign it */ cp = alloc(sizeof(struct env) - ALLOC_SIZE, ATEMP); /* undo what alloc() did to the malloc result address */ ep = (void *)(cp - ALLOC_SIZE); /* initialise public members of struct env (not the ALLOC_ITEM) */ ainit(&ep->area); ep->oenv = e; ep->loc = e->loc; ep->savefd = NULL; ep->temps = NULL; ep->yyrecursive_statep = NULL; ep->type = type; ep->flags = 0; /* jump buffer is invalid because flags == 0 */ e = ep; } void quitenv(struct shf *shf) { struct env *ep = e; char *cp; int fd; yyrecursive_pop(true); while (ep->oenv && ep->oenv->loc != ep->loc) popblock(); if (ep->savefd != NULL) { for (fd = 0; fd < NUFILE; fd++) /* if ep->savefd[fd] < 0, means fd was closed */ if (ep->savefd[fd]) restfd(fd, ep->savefd[fd]); if (ep->savefd[2]) /* Clear any write errors */ shf_reopen(2, SHF_WR, shl_out); } /* * Bottom of the stack. * Either main shell is exiting or cleanup_parents_env() was called. */ if (ep->oenv == NULL) { #ifdef DEBUG_LEAKS int i; #endif if (ep->type == E_NONE) { /* Main shell exiting? */ #if HAVE_PERSISTENT_HISTORY if (Flag(FTALKING)) hist_finish(); #endif j_exit(); if (ep->flags & EF_FAKE_SIGDIE) { int sig = (exstat & 0xFF) - 128; /* * ham up our death a bit (AT&T ksh * only seems to do this for SIGTERM) * Don't do it for SIGQUIT, since we'd * dump a core.. */ if ((sig == SIGINT || sig == SIGTERM) && (kshpgrp == kshpid)) { setsig(&sigtraps[sig], SIG_DFL, SS_RESTORE_CURR | SS_FORCE); kill(0, sig); } } } if (shf) shf_close(shf); reclaim(); #ifdef DEBUG_LEAKS #ifndef MKSH_NO_CMDLINE_EDITING x_done(); #endif #ifndef MKSH_NOPROSPECTOFWORK /* block at least SIGCHLD during/after afreeall */ sigprocmask(SIG_BLOCK, &sm_sigchld, NULL); #endif afreeall(APERM); for (fd = 3; fd < NUFILE; fd++) if ((i = fcntl(fd, F_GETFD, 0)) != -1 && (i & FD_CLOEXEC)) close(fd); close(2); close(1); close(0); #endif exit(exstat & 0xFF); } if (shf) shf_close(shf); reclaim(); e = e->oenv; /* free the struct env - tricky due to the ALLOC_ITEM inside */ cp = (void *)ep; afree(cp + ALLOC_SIZE, ATEMP); } /* Called after a fork to cleanup stuff left over from parents environment */ void cleanup_parents_env(void) { struct env *ep; int fd; mkssert(e != NULL); /* * Don't clean up temporary files - parent will probably need them. * Also, can't easily reclaim memory since variables, etc. could be * anywhere. */ /* close all file descriptors hiding in savefd */ for (ep = e; ep; ep = ep->oenv) { if (ep->savefd) { for (fd = 0; fd < NUFILE; fd++) if (ep->savefd[fd] > 0) close(ep->savefd[fd]); afree(ep->savefd, &ep->area); ep->savefd = NULL; } #ifdef DEBUG_LEAKS if (ep->type != E_NONE) ep->type = E_GONE; #endif } #ifndef DEBUG_LEAKS e->oenv = NULL; #endif } /* Called just before an execve cleanup stuff temporary files */ void cleanup_proc_env(void) { struct env *ep; for (ep = e; ep; ep = ep->oenv) remove_temps(ep->temps); } /* remove temp files and free ATEMP Area */ static void reclaim(void) { struct block *l; while ((l = e->loc) && (!e->oenv || e->oenv->loc != l)) { e->loc = l->next; afreeall(&l->area); } remove_temps(e->temps); e->temps = NULL; afreeall(&e->area); } static void remove_temps(struct temp *tp) { for (; tp != NULL; tp = tp->next) if (tp->pid == procpid) unlink(tp->tffn); } /* * Initialise tty_fd. Used for tracking the size of the terminal, * saving/resetting tty modes upon forground job completion, and * for setting up the tty process group. Return values: * 0 = got controlling tty * 1 = got terminal but no controlling tty * 2 = cannot find a terminal * 3 = cannot dup fd * 4 = cannot make fd close-on-exec * An existing tty_fd is cached if no "better" one could be found, * i.e. if tty_devtty was already set or the new would not set it. */ int tty_init_fd(void) { int fd, rv, eno = 0; bool do_close = false, is_devtty = true; if (tty_devtty) { /* already got a tty which is /dev/tty */ return (0); } #ifdef _UWIN /*XXX imake style */ if (isatty(3)) { /* fd 3 on UWIN _is_ /dev/tty (or our controlling tty) */ fd = 3; goto got_fd; } #endif if ((fd = open("/dev/tty", O_RDWR, 0)) >= 0) { do_close = true; goto got_fd; } eno = errno; if (tty_fd >= 0) { /* already got a non-devtty one */ rv = 1; goto out; } is_devtty = false; if (isatty((fd = 0)) || isatty((fd = 2))) goto got_fd; /* cannot find one */ rv = 2; /* assert: do_close == false */ goto out; got_fd: if ((rv = fcntl(fd, F_DUPFD, FDBASE)) < 0) { eno = errno; rv = 3; goto out; } if (fcntl(rv, F_SETFD, FD_CLOEXEC) < 0) { eno = errno; close(rv); rv = 4; goto out; } tty_fd = rv; tty_devtty = is_devtty; rv = eno = 0; out: if (do_close) close(fd); errno = eno; return (rv); } /* A shell error occurred (eg, syntax error, etc.) */ #define VWARNINGF_ERRORPREFIX 1 #define VWARNINGF_FILELINE 2 #define VWARNINGF_BUILTIN 4 #define VWARNINGF_INTERNAL 8 static void vwarningf(unsigned int, const char *, va_list) MKSH_A_FORMAT(__printf__, 2, 0); static void vwarningf(unsigned int flags, const char *fmt, va_list ap) { if (fmt) { if (flags & VWARNINGF_INTERNAL) shf_fprintf(shl_out, "internal error: "); if (flags & VWARNINGF_ERRORPREFIX) error_prefix(tobool(flags & VWARNINGF_FILELINE)); if ((flags & VWARNINGF_BUILTIN) && /* not set when main() calls parse_args() */ builtin_argv0 && builtin_argv0 != kshname) shf_fprintf(shl_out, "%s: ", builtin_argv0); shf_vfprintf(shl_out, fmt, ap); shf_putchar('\n', shl_out); } shf_flush(shl_out); } void errorfx(int rc, const char *fmt, ...) { va_list va; exstat = rc; /* debugging: note that stdout not valid */ shl_stdout_ok = false; va_start(va, fmt); vwarningf(VWARNINGF_ERRORPREFIX | VWARNINGF_FILELINE, fmt, va); va_end(va); unwind(LERROR); } void errorf(const char *fmt, ...) { va_list va; exstat = 1; /* debugging: note that stdout not valid */ shl_stdout_ok = false; va_start(va, fmt); vwarningf(VWARNINGF_ERRORPREFIX | VWARNINGF_FILELINE, fmt, va); va_end(va); unwind(LERROR); } /* like errorf(), but no unwind is done */ void warningf(bool fileline, const char *fmt, ...) { va_list va; va_start(va, fmt); vwarningf(VWARNINGF_ERRORPREFIX | (fileline ? VWARNINGF_FILELINE : 0), fmt, va); va_end(va); } /* * Used by built-in utilities to prefix shell and utility name to message * (also unwinds environments for special builtins). */ void bi_errorf(const char *fmt, ...) { va_list va; /* debugging: note that stdout not valid */ shl_stdout_ok = false; exstat = 1; va_start(va, fmt); vwarningf(VWARNINGF_ERRORPREFIX | VWARNINGF_FILELINE | VWARNINGF_BUILTIN, fmt, va); va_end(va); /* * POSIX special builtins and ksh special builtins cause * non-interactive shells to exit. * XXX odd use of KEEPASN; also may not want LERROR here */ if (builtin_flag & SPEC_BI) { builtin_argv0 = NULL; unwind(LERROR); } } /* Called when something that shouldn't happen does */ void internal_errorf(const char *fmt, ...) { va_list va; va_start(va, fmt); vwarningf(VWARNINGF_INTERNAL, fmt, va); va_end(va); unwind(LERROR); } void internal_warningf(const char *fmt, ...) { va_list va; va_start(va, fmt); vwarningf(VWARNINGF_INTERNAL, fmt, va); va_end(va); } /* used by error reporting functions to print "ksh: .kshrc[25]: " */ void error_prefix(bool fileline) { /* Avoid foo: foo[2]: ... */ if (!fileline || !source || !source->file || strcmp(source->file, kshname) != 0) shf_fprintf(shl_out, "%s: ", kshname + (*kshname == '-')); if (fileline && source && source->file != NULL) { shf_fprintf(shl_out, "%s[%d]: ", source->file, source->errline > 0 ? source->errline : source->line); source->errline = 0; } } /* printf to shl_out (stderr) with flush */ void shellf(const char *fmt, ...) { va_list va; if (!initio_done) /* shl_out may not be set up yet... */ return; va_start(va, fmt); shf_vfprintf(shl_out, fmt, va); va_end(va); shf_flush(shl_out); } /* printf to shl_stdout (stdout) */ void shprintf(const char *fmt, ...) { va_list va; if (!shl_stdout_ok) internal_errorf("shl_stdout not valid"); va_start(va, fmt); shf_vfprintf(shl_stdout, fmt, va); va_end(va); } /* test if we can seek backwards fd (returns 0 or SHF_UNBUF) */ int can_seek(int fd) { struct stat statb; return (fstat(fd, &statb) == 0 && !S_ISREG(statb.st_mode) ? SHF_UNBUF : 0); } #ifdef DF int shl_dbg_fd; #define NSHF_IOB 4 #else #define NSHF_IOB 3 #endif struct shf shf_iob[NSHF_IOB]; void initio(void) { #ifdef DF const char *lfp; #endif /* force buffer allocation */ shf_fdopen(1, SHF_WR, shl_stdout); shf_fdopen(2, SHF_WR, shl_out); shf_fdopen(2, SHF_WR, shl_xtrace); #ifdef DF if ((lfp = getenv("SDMKSH_PATH")) == NULL) { if ((lfp = getenv("HOME")) == NULL || *lfp != '/') errorf("cannot get home directory"); lfp = shf_smprintf("%s/mksh-dbg.txt", lfp); } if ((shl_dbg_fd = open(lfp, O_WRONLY | O_APPEND | O_CREAT, 0600)) < 0) errorf("cannot open debug output file %s", lfp); if (shl_dbg_fd < FDBASE) { int nfd; nfd = fcntl(shl_dbg_fd, F_DUPFD, FDBASE); close(shl_dbg_fd); if ((shl_dbg_fd = nfd) == -1) errorf("cannot dup debug output file"); } fcntl(shl_dbg_fd, F_SETFD, FD_CLOEXEC); shf_fdopen(shl_dbg_fd, SHF_WR, shl_dbg); DF("=== open ==="); #endif initio_done = true; } /* A dup2() with error checking */ int ksh_dup2(int ofd, int nfd, bool errok) { int rv; if (((rv = dup2(ofd, nfd)) < 0) && !errok && (errno != EBADF)) errorf("too many files open in shell"); #ifdef __ultrix /*XXX imake style */ if (rv >= 0) fcntl(nfd, F_SETFD, 0); #endif return (rv); } /* * Move fd from user space (0 <= fd < 10) to shell space (fd >= 10), * set close-on-exec flag. See FDBASE in sh.h, maybe 24 not 10 here. */ short savefd(int fd) { int nfd = fd; if (fd < FDBASE && (nfd = fcntl(fd, F_DUPFD, FDBASE)) < 0 && errno == EBADF) return (-1); if (nfd < 0 || nfd > SHRT_MAX) errorf("too many files open in shell"); fcntl(nfd, F_SETFD, FD_CLOEXEC); return ((short)nfd); } void restfd(int fd, int ofd) { if (fd == 2) shf_flush(&shf_iob[/* fd */ 2]); if (ofd < 0) /* original fd closed */ close(fd); else if (fd != ofd) { /*XXX: what to do if this dup fails? */ ksh_dup2(ofd, fd, true); close(ofd); } } void openpipe(int *pv) { int lpv[2]; if (pipe(lpv) < 0) errorf("can't create pipe - try again"); pv[0] = savefd(lpv[0]); if (pv[0] != lpv[0]) close(lpv[0]); pv[1] = savefd(lpv[1]); if (pv[1] != lpv[1]) close(lpv[1]); } void closepipe(int *pv) { close(pv[0]); close(pv[1]); } /* * Called by iosetup() (deals with 2>&4, etc.), c_read, c_print to turn * a string (the X in 2>&X, read -uX, print -uX) into a file descriptor. */ int check_fd(const char *name, int mode, const char **emsgp) { int fd, fl; if (name[0] == 'p' && !name[1]) return (coproc_getfd(mode, emsgp)); for (fd = 0; ksh_isdigit(*name); ++name) fd = (fd * 10) + *name - '0'; if (*name || fd >= FDBASE) { if (emsgp) *emsgp = "illegal file descriptor name"; return (-1); } if ((fl = fcntl(fd, F_GETFL, 0)) < 0) { if (emsgp) *emsgp = "bad file descriptor"; return (-1); } fl &= O_ACCMODE; /* * X_OK is a kludge to disable this check for dups (x<&1): * historical shells never did this check (XXX don't know what * POSIX has to say). */ if (!(mode & X_OK) && fl != O_RDWR && ( ((mode & R_OK) && fl != O_RDONLY) || ((mode & W_OK) && fl != O_WRONLY))) { if (emsgp) *emsgp = (fl == O_WRONLY) ? "fd not open for reading" : "fd not open for writing"; return (-1); } return (fd); } /* Called once from main */ void coproc_init(void) { coproc.read = coproc.readw = coproc.write = -1; coproc.njobs = 0; coproc.id = 0; } /* Called by c_read() when eof is read - close fd if it is the co-process fd */ void coproc_read_close(int fd) { if (coproc.read >= 0 && fd == coproc.read) { coproc_readw_close(fd); close(coproc.read); coproc.read = -1; } } /* * Called by c_read() and by iosetup() to close the other side of the * read pipe, so reads will actually terminate. */ void coproc_readw_close(int fd) { if (coproc.readw >= 0 && coproc.read >= 0 && fd == coproc.read) { close(coproc.readw); coproc.readw = -1; } } /* * Called by c_print when a write to a fd fails with EPIPE and by iosetup * when co-process input is dup'd */ void coproc_write_close(int fd) { if (coproc.write >= 0 && fd == coproc.write) { close(coproc.write); coproc.write = -1; } } /* * Called to check for existence of/value of the co-process file descriptor. * (Used by check_fd() and by c_read/c_print to deal with -p option). */ int coproc_getfd(int mode, const char **emsgp) { int fd = (mode & R_OK) ? coproc.read : coproc.write; if (fd >= 0) return (fd); if (emsgp) *emsgp = "no coprocess"; return (-1); } /* * called to close file descriptors related to the coprocess (if any) * Should be called with SIGCHLD blocked. */ void coproc_cleanup(int reuse) { /* This to allow co-processes to share output pipe */ if (!reuse || coproc.readw < 0 || coproc.read < 0) { if (coproc.read >= 0) { close(coproc.read); coproc.read = -1; } if (coproc.readw >= 0) { close(coproc.readw); coproc.readw = -1; } } if (coproc.write >= 0) { close(coproc.write); coproc.write = -1; } } struct temp * maketemp(Area *ap, Temp_type type, struct temp **tlist) { char *cp; size_t len; int i, j; struct temp *tp; const char *dir; struct stat sb; dir = tmpdir ? tmpdir : MKSH_DEFAULT_TMPDIR; /* add "/shXXXXXX.tmp" plus NUL */ len = strlen(dir); checkoktoadd(len, offsetof(struct temp, tffn[0]) + 14); tp = alloc(offsetof(struct temp, tffn[0]) + 14 + len, ap); tp->shf = NULL; tp->pid = procpid; tp->type = type; if (stat(dir, &sb) || !S_ISDIR(sb.st_mode)) { tp->tffn[0] = '\0'; goto maketemp_out; } cp = (void *)tp; cp += offsetof(struct temp, tffn[0]); memcpy(cp, dir, len); cp += len; memcpy(cp, "/shXXXXXX.tmp", 14); /* point to the first of six Xes */ cp += 3; /* generate random part of filename */ len = -1; do { i = rndget() % 36; cp[++len] = i < 26 ? 'a' + i : '0' + i - 26; } while (len < 5); /* cyclically attempt to open a temporary file */ while ((i = open(tp->tffn, O_CREAT | O_EXCL | O_RDWR, 0600)) < 0) { if (errno != EEXIST) goto maketemp_out; /* count down from z to a then from 9 to 0 */ while (cp[len] == '0') if (!len--) goto maketemp_out; if (cp[len] == 'a') cp[len] = '9'; else --cp[len]; /* do another cycle */ } if (type == TT_FUNSUB) { /* map us high and mark as close-on-exec */ if ((j = savefd(i)) != i) { close(i); i = j; } /* operation mode for the shf */ j = SHF_RD; } else j = SHF_WR; /* shf_fdopen cannot fail, so no fd leak */ tp->shf = shf_fdopen(i, j, NULL); maketemp_out: tp->next = *tlist; *tlist = tp; return (tp); } /* * We use a similar collision resolution algorithm as Python 2.5.4 * but with a slightly tweaked implementation written from scratch. */ #define INIT_TBLSHIFT 3 /* initial table shift (2^3 = 8) */ #define PERTURB_SHIFT 5 /* see Python 2.5.4 Objects/dictobject.c */ static void tgrow(struct table *); static int tnamecmp(const void *, const void *); static void tgrow(struct table *tp) { size_t i, j, osize, mask, perturb; struct tbl *tblp, **pp; struct tbl **ntblp, **otblp = tp->tbls; if (tp->tshift > 29) internal_errorf("hash table size limit reached"); /* calculate old size, new shift and new size */ osize = (size_t)1 << (tp->tshift++); i = osize << 1; ntblp = alloc2(i, sizeof(struct tbl *), tp->areap); /* multiplication cannot overflow: alloc2 checked that */ memset(ntblp, 0, i * sizeof(struct tbl *)); /* table can get very full when reaching its size limit */ tp->nfree = (tp->tshift == 30) ? 0x3FFF0000UL : /* but otherwise, only 75% */ ((i * 3) / 4); tp->tbls = ntblp; if (otblp == NULL) return; mask = i - 1; for (i = 0; i < osize; i++) if ((tblp = otblp[i]) != NULL) { if ((tblp->flag & DEFINED)) { /* search for free hash table slot */ j = perturb = tblp->ua.hval; goto find_first_empty_slot; find_next_empty_slot: j = (j << 2) + j + perturb + 1; perturb >>= PERTURB_SHIFT; find_first_empty_slot: pp = &ntblp[j & mask]; if (*pp != NULL) goto find_next_empty_slot; /* found an empty hash table slot */ *pp = tblp; tp->nfree--; } else if (!(tblp->flag & FINUSE)) { afree(tblp, tp->areap); } } afree(otblp, tp->areap); } void ktinit(Area *ap, struct table *tp, uint8_t initshift) { tp->areap = ap; tp->tbls = NULL; tp->tshift = ((initshift > INIT_TBLSHIFT) ? initshift : INIT_TBLSHIFT) - 1; tgrow(tp); } /* table, name (key) to search for, hash(name), rv pointer to tbl ptr */ struct tbl * ktscan(struct table *tp, const char *name, uint32_t h, struct tbl ***ppp) { size_t j, perturb, mask; struct tbl **pp, *p; mask = ((size_t)1 << (tp->tshift)) - 1; /* search for hash table slot matching name */ j = perturb = h; goto find_first_slot; find_next_slot: j = (j << 2) + j + perturb + 1; perturb >>= PERTURB_SHIFT; find_first_slot: pp = &tp->tbls[j & mask]; if ((p = *pp) != NULL && (p->ua.hval != h || !(p->flag & DEFINED) || strcmp(p->name, name))) goto find_next_slot; /* p == NULL if not found, correct found entry otherwise */ if (ppp) *ppp = pp; return (p); } /* table, name (key) to enter, hash(n) */ struct tbl * ktenter(struct table *tp, const char *n, uint32_t h) { struct tbl **pp, *p; size_t len; Search: if ((p = ktscan(tp, n, h, &pp))) return (p); if (tp->nfree == 0) { /* too full */ tgrow(tp); goto Search; } /* create new tbl entry */ len = strlen(n); checkoktoadd(len, offsetof(struct tbl, name[0]) + 1); p = alloc(offsetof(struct tbl, name[0]) + ++len, tp->areap); p->flag = 0; p->type = 0; p->areap = tp->areap; p->ua.hval = h; p->u2.field = 0; p->u.array = NULL; memcpy(p->name, n, len); /* enter in tp->tbls */ tp->nfree--; *pp = p; return (p); } void ktwalk(struct tstate *ts, struct table *tp) { ts->left = (size_t)1 << (tp->tshift); ts->next = tp->tbls; } struct tbl * ktnext(struct tstate *ts) { while (--ts->left >= 0) { struct tbl *p = *ts->next++; if (p != NULL && (p->flag & DEFINED)) return (p); } return (NULL); } static int tnamecmp(const void *p1, const void *p2) { const struct tbl *a = *((const struct tbl * const *)p1); const struct tbl *b = *((const struct tbl * const *)p2); return (strcmp(a->name, b->name)); } struct tbl ** ktsort(struct table *tp) { size_t i; struct tbl **p, **sp, **dp; /* * since the table is never entirely full, no need to reserve * additional space for the trailing NULL appended below */ i = (size_t)1 << (tp->tshift); p = alloc2(i, sizeof(struct tbl *), ATEMP); sp = tp->tbls; /* source */ dp = p; /* dest */ while (i--) if ((*dp = *sp++) != NULL && (((*dp)->flag & DEFINED) || ((*dp)->flag & ARRAY))) dp++; qsort(p, (i = dp - p), sizeof(struct tbl *), tnamecmp); p[i] = NULL; return (p); } #ifdef SIGWINCH static void x_sigwinch(int sig MKSH_A_UNUSED) { /* this runs inside interrupt context, with errno saved */ got_winch = 1; } #endif #ifdef DF void DF(const char *fmt, ...) { va_list args; struct timeval tv; mirtime_mjd mjd; mksh_lockfd(shl_dbg_fd); mksh_TIME(tv); timet2mjd(&mjd, tv.tv_sec); shf_fprintf(shl_dbg, "[%02u:%02u:%02u (%u) %u.%06u] ", (unsigned)mjd.sec / 3600, ((unsigned)mjd.sec / 60) % 60, (unsigned)mjd.sec % 60, (unsigned)getpid(), (unsigned)tv.tv_sec, (unsigned)tv.tv_usec); va_start(args, fmt); shf_vfprintf(shl_dbg, fmt, args); va_end(args); shf_putc('\n', shl_dbg); shf_flush(shl_dbg); mksh_unlkfd(shl_dbg_fd); } #endif void x_mkraw(int fd, mksh_ttyst *ocb, bool forread) { mksh_ttyst cb; if (ocb) mksh_tcget(fd, ocb); else ocb = &tty_state; cb = *ocb; if (forread) { cb.c_lflag &= ~(ICANON) | ECHO; } else { cb.c_iflag &= ~(INLCR | ICRNL); cb.c_lflag &= ~(ISIG | ICANON | ECHO); } #if defined(VLNEXT) && defined(_POSIX_VDISABLE) /* OSF/1 processes lnext when ~icanon */ cb.c_cc[VLNEXT] = _POSIX_VDISABLE; #endif /* SunOS 4.1.x & OSF/1 processes discard(flush) when ~icanon */ #if defined(VDISCARD) && defined(_POSIX_VDISABLE) cb.c_cc[VDISCARD] = _POSIX_VDISABLE; #endif cb.c_cc[VTIME] = 0; cb.c_cc[VMIN] = 1; mksh_tcset(fd, &cb); }