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main.c
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main.c
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/* $OpenBSD: main.c,v 1.57 2015/09/10 22:48:58 nicm Exp $ */
/* $OpenBSD: tty.c,v 1.10 2014/08/10 02:44:26 guenther Exp $ */
/* $OpenBSD: io.c,v 1.26 2015/09/11 08:00:27 guenther Exp $ */
/* $OpenBSD: table.c,v 1.16 2015/09/01 13:12:31 tedu Exp $ */
/*-
* Copyright (c) 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010,
* 2011, 2012, 2013, 2014, 2015, 2016
* mirabilos <[email protected]>
*
* 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 1.310 2016/02/26 21:53:36 tg Exp $");
extern char **environ;
#ifndef MKSHRC_PATH
#define MKSHRC_PATH "~/.mkshrc"
#endif
#ifndef MKSH_DEFAULT_TMPDIR
#define MKSH_DEFAULT_TMPDIR MKSH_UNIXROOT "/tmp"
#endif
static uint8_t isuc(const char *);
static int main_init(int, const char *[], Source **, struct block **);
void chvt_reinit(void);
static void reclaim(void);
static void remove_temps(struct temp *);
static mksh_uari_t rndsetup(void);
#ifdef SIGWINCH
static void x_sigwinch(int);
#endif
static const char initifs[] = "IFS= \t\n";
static const char initsubs[] =
"${PS2=> } ${PS3=#? } ${PS4=+ } ${SECONDS=0} ${TMOUT=0} ${EPOCHREALTIME=}";
static const char *initcoms[] = {
Ttypeset, "-r", initvsn, NULL,
Ttypeset, "-x", "HOME", "PATH", "SHELL", NULL,
Ttypeset, "-i10", "COLUMNS", "LINES", "SECONDS", "TMOUT", NULL,
Talias,
"integer=\\typeset -i",
"local=\\typeset",
/* not "alias -t --": hash -r needs to work */
"hash=\\builtin alias -t",
"type=\\builtin whence -v",
"autoload=\\typeset -fu",
"functions=\\typeset -f",
"history=\\builtin fc -l",
"nameref=\\typeset -n",
"nohup=nohup ",
"r=\\builtin fc -e -",
"login=\\exec login",
NULL,
/* this is what AT&T ksh seems to track, with the addition of emacs */
Talias, "-tU",
Tcat, "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) - sizeof(ALLOC_ITEM), APERM);
#ifdef DEBUG
/* clear the allocated space, for valgrind */
memset(cp, 0, sizeof(*bufptr) - sizeof(ALLOC_ITEM));
#endif
/* undo what alloc() did to the malloc result address */
bufptr = (void *)(cp - sizeof(ALLOC_ITEM));
/* 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);
#ifdef MKSH_ALLOC_CATCH_UNDERRUNS
mprotect(((char *)bufptr) + 4096, 4096, PROT_READ | PROT_WRITE);
#endif
h = chvt_rndsetup(bufptr, sizeof(*bufptr));
afree(cp, APERM);
return ((mksh_uari_t)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_shell, 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
#ifdef __OS2__
for (i = 0; i < 3; ++i)
if (!isatty(i))
setmode(i, O_BINARY);
#endif
/* do things like getpgrp() et al. */
chvt_reinit();
/* make sure argv[] is sane, for weird OSes */
if (!*argv) {
argv = empty_argv;
argc = 1;
}
kshname = argv[0];
/* initialise permanent Area */
ainit(&aperm);
/* max. name length: -2147483648 = 11 (+ NUL) */
vtemp = alloc(offsetof(struct tbl, name[0]) + 12, 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];
/*
* Turn on nohup by default. (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;
/* define built-in commands and see if we were called as one */
ktinit(APERM, &builtins,
/* currently up to 54 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" MKSH_EXE_EXT)) {
/* 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 = MKSH_UNIXROOT "/bin" MKSH_PATHSEPS
MKSH_UNIXROOT "/usr/bin" MKSH_PATHSEPS
MKSH_UNIXROOT "/sbin" MKSH_PATHSEPS
MKSH_UNIXROOT "/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);
#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) {
wp = (const char **)environ;
while (*wp != NULL) {
rndpush(*wp);
typeset(*wp, IMPORT | EXPORT, 0, 0, 0);
++wp;
}
}
/* 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 $PWD if it is valid */
set_current_wd((mksh_abspath(cp) && test_eval(NULL, TO_FILEQ, cp, ".",
true)) ? cp : NULL);
if (current_wd[0])
simplify_path(current_wd);
/* Only set pwd if we know where we are or if it had a bogus value */
if (current_wd[0] || *cp)
/* setstr can't fail here */
setstr(vp, current_wd, KSH_RETURN_ERROR);
for (wp = initcoms; *wp != NULL; wp++) {
shcomexec(wp);
while (*wp != NULL)
wp++;
}
setint_n(global("OPTIND"), 1, 10);
kshuid = getuid();
kshgid = getgid();
kshegid = getegid();
safe_prompt = ksheuid ? "$ " : "# ";
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) ? 2 : 0;
/* 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);
}
/* 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("-c %s", "requires an argument");
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;
#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);
#ifdef __OS2__
/*
* A bug in OS/2 extproc (like shebang) handling makes
* it not pass the full pathname of a script, so we need
* to search for it. This changes the behaviour of a
* simple "mksh foo", but can't be helped.
*/
s->file = search_path(argv[argi++], path, X_OK, NULL);
if (!s->file || !*s->file)
s->file = argv[argi - 1];
#else
s->file = argv[argi++];
#endif
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;
#else /* this may not be an #elif */
#if MKSH_ASSUME_UTF8
utf_flag = 1;
#else
/* always disable UTF-8 (for interactive) */
utf_flag = 0;
#endif
#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_shell = Flag(FRESTRICTED);
Flag(FRESTRICTED) = 0;
errexit = Flag(FERREXIT);
Flag(FERREXIT) = 0;
/*
* Do this before profile/$ENV so that if it causes problems in them,
* user will know why things broke.
*/
if (!current_wd[0] && Flag(FTALKING))
warningf(false, "can't determine current directory");
if (Flag(FLOGIN))
include(MKSH_SYSTEM_PROFILE, 0, NULL, true);
if (!Flag(FPRIVILEGED)) {
if (Flag(FLOGIN))
include(substitute("$HOME/.profile", 0), 0, NULL, true);
if (Flag(FTALKING)) {
cp = substitute(substitute("${ENV:-" MKSHRC_PATH "}",
0), DOTILDE);
if (cp[0] != '\0')
include(cp, 0, NULL, true);
}
} else {
include(MKSH_SUID_PROFILE, 0, NULL, true);
/* turn off -p if not set explicitly */
if (Flag(FPRIVILEGED) != 1)
change_flag(FPRIVILEGED, OF_INTERNAL, false);
}
if (restricted_shell) {
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("include %d", 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("shell %d", 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);
if (interactive)
histsave(&s->line, NULL, HIST_FLUSH, true);
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;
}
} else if ((s->flags & SF_MAYEXEC) && t->type == TCOM)
t->u.evalflags |= DOTCOMEXEC;
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);
/*
* quitenv() may have reclaimed the memory
* used by source which will end badly when
* we jump to a function that expects it to
* be valid
*/
source = 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) - sizeof(ALLOC_ITEM), ATEMP);
/* undo what alloc() did to the malloc result address */
ep = (void *)(cp - sizeof(ALLOC_ITEM));
/* 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);
}
}