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exec.c
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exec.c
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/* $NetBSD: exec.c,v 1.24 2017/07/01 23:12:08 joerg Exp $ */
/*
* execute command tree
*/
#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: exec.c,v 1.24 2017/07/01 23:12:08 joerg Exp $");
#endif
#include <sys/stat.h>
#include <ctype.h>
#include <stdbool.h>
#include "sh.h"
#include "c_test.h"
/* Does ps4 get parameter substitutions done? */
#ifdef KSH
# define PS4_SUBSTITUTE(s) substitute((s), 0)
#else
# define PS4_SUBSTITUTE(s) (s)
#endif /* KSH */
static int comexec ARGS((struct op *, struct tbl *volatile, char **,
int volatile));
static void scriptexec ARGS((struct op *, char **));
static int call_builtin ARGS((struct tbl *, char **));
static int iosetup ARGS((struct ioword *, struct tbl *));
static int herein ARGS((const char *, int));
#ifdef KSH
static char *do_selectargs(char **, bool);
#endif /* KSH */
#ifdef KSH
static int dbteste_isa ARGS((Test_env *, Test_meta));
static const char *dbteste_getopnd ARGS((Test_env *, Test_op, int));
static int dbteste_eval ARGS((Test_env *, Test_op, const char *,
const char *, int));
static void dbteste_error ARGS((Test_env *, int, const char *));
#endif /* KSH */
/*
* handle systems that don't have F_SETFD
*/
#ifndef F_SETFD
# ifndef MAXFD
# define MAXFD 64
# endif
/* a bit field would be smaller, but this will work */
static char clexec_tab[MAXFD+1];
#endif
/*
* we now use this function always.
*/
int
fd_clexec(fd)
int fd;
{
#ifndef F_SETFD
if (fd >= 0 && fd < sizeof(clexec_tab)) {
clexec_tab[fd] = 1;
return 0;
}
return -1;
#else
return fcntl(fd, F_SETFD, 1);
#endif
}
/*
* execute command tree
*/
int
execute(t, flags)
struct op * volatile t;
volatile int flags; /* if XEXEC don't fork */
{
int i;
volatile int rv = 0;
int pv[2];
char ** volatile ap;
char *s, *cp;
struct ioword **iowp;
struct tbl *tp = NULL;
if (t == NULL)
return 0;
/* Is this the end of a pipeline? If so, we want to evaluate the
* command arguments
bool eval_done = false;
if ((flags&XFORK) && !(flags&XEXEC) && (flags&XPCLOSE)) {
eval_done = true;
tp = eval_execute_args(t, &ap);
}
*/
if ((flags&XFORK) && !(flags&XEXEC) && t->type != TPIPE)
return exchild(t, flags & ~XTIME, -1); /* run in sub-process */
newenv(E_EXEC);
if (trap)
runtraps(0);
if (t->type == TCOM) {
/* Clear subst_exstat before argument expansion. Used by
* null commands (see comexec() and c_eval()) and by c_set().
*/
subst_exstat = 0;
current_lineno = t->lineno; /* for $LINENO */
/* POSIX says expand command words first, then redirections,
* and assignments last..
*/
ap = eval(t->args, t->u.evalflags | DOBLANK | DOGLOB | DOTILDE);
if (flags & XTIME)
/* Allow option parsing (bizarre, but POSIX) */
timex_hook(t, &ap);
if (Flag(FXTRACE) && ap[0]) {
shf_fprintf(shl_out, "%s",
PS4_SUBSTITUTE(str_val(global("PS4"))));
for (i = 0; ap[i]; i++)
shf_fprintf(shl_out, "%s%s", ap[i],
ap[i + 1] ? space : newline);
shf_flush(shl_out);
}
if (ap[0])
tp = findcom(ap[0], FC_BI|FC_FUNC);
}
flags &= ~XTIME;
if (t->ioact != NULL || t->type == TPIPE || t->type == TCOPROC) {
e->savefd = (short *) alloc(sizeofN(short, NUFILE), ATEMP);
/* initialize to not redirected */
memset(e->savefd, 0, sizeofN(short, NUFILE));
}
/* do redirection, to be restored in quitenv() */
if (t->ioact != NULL)
for (iowp = t->ioact; *iowp != NULL; iowp++) {
if (iosetup(*iowp, tp) < 0) {
exstat = rv = 1;
/* Redirection failures for special commands
* cause (non-interactive) shell to exit.
*/
if (tp && tp->type == CSHELL
&& (tp->flag & SPEC_BI))
errorf("%s", null);
/* Deal with FERREXIT, quitenv(), etc. */
goto Break;
}
}
switch(t->type) {
case TCOM:
rv = comexec(t, tp, ap, flags);
break;
case TPAREN:
rv = execute(t->left, flags|XFORK);
break;
case TPIPE:
flags |= XFORK;
flags &= ~XEXEC;
e->savefd[0] = savefd(0, 0);
(void) ksh_dup2(e->savefd[0], 0, false); /* stdin of first */
e->savefd[1] = savefd(1, 0);
while (t->type == TPIPE) {
openpipe(pv);
(void) ksh_dup2(pv[1], 1, false); /* stdout of curr */
/* Let exchild() close pv[0] in child
* (if this isn't done, commands like
* (: ; cat /etc/termcap) | sleep 1
* will hang forever).
*/
exchild(t->left, flags|XPIPEO|XCCLOSE, pv[0]);
(void) ksh_dup2(pv[0], 0, false); /* stdin of next */
closepipe(pv);
flags |= XPIPEI;
t = t->right;
}
restfd(1, e->savefd[1]); /* stdout of last */
e->savefd[1] = 0; /* no need to re-restore this */
/* Let exchild() close 0 in parent, after fork, before wait */
i = exchild(t, flags|XPCLOSE, 0);
if (!(flags&XBGND) && !(flags&XXCOM))
rv = i;
break;
case TLIST:
while (t->type == TLIST) {
execute(t->left, flags & XERROK);
t = t->right;
}
rv = execute(t, flags & XERROK);
break;
#ifdef KSH
case TCOPROC:
{
sigset_t omask;
/* Block sigchild as we are using things changed in the
* signal handler
*/
sigprocmask(SIG_BLOCK, &sm_sigchld, &omask);
e->type = E_ERRH;
i = ksh_sigsetjmp(e->jbuf, 0);
if (i) {
sigprocmask(SIG_SETMASK, &omask, (sigset_t *) 0);
quitenv();
unwind(i);
/*NOTREACHED*/
}
/* Already have a (live) co-process? */
if (coproc.job && coproc.write >= 0)
errorf("coprocess already exists");
/* Can we re-use the existing co-process pipe? */
coproc_cleanup(true);
/* do this before opening pipes, in case these fail */
e->savefd[0] = savefd(0, 0);
e->savefd[1] = savefd(1, 0);
openpipe(pv);
if (pv[0] != 0) {
ksh_dup2(pv[0], 0, false);
close(pv[0]);
}
coproc.write = pv[1];
coproc.job = (void *) 0;
if (coproc.readw >= 0)
ksh_dup2(coproc.readw, 1, false);
else {
openpipe(pv);
coproc.read = pv[0];
ksh_dup2(pv[1], 1, false);
coproc.readw = pv[1]; /* closed before first read */
coproc.njobs = 0;
/* create new coprocess id */
++coproc.id;
}
sigprocmask(SIG_SETMASK, &omask, (sigset_t *) 0);
e->type = E_EXEC; /* no more need for error handler */
/* exchild() closes coproc.* in child after fork,
* will also increment coproc.njobs when the
* job is actually created.
*/
flags &= ~XEXEC;
exchild(t->left, flags|XBGND|XFORK|XCOPROC|XCCLOSE,
coproc.readw);
break;
}
#endif /* KSH */
case TASYNC:
/* XXX non-optimal, I think - "(foo &)", forks for (),
* forks again for async... parent should optimize
* this to "foo &"...
*/
rv = execute(t->left, (flags&~XEXEC)|XBGND|XFORK);
break;
case TOR:
case TAND:
rv = execute(t->left, XERROK);
if (t->right != NULL && (rv == 0) == (t->type == TAND))
rv = execute(t->right, flags & XERROK);
else
flags |= XERROK;
break;
case TBANG:
rv = !execute(t->right, XERROK);
break;
#ifdef KSH
case TDBRACKET:
{
Test_env te;
te.flags = TEF_DBRACKET;
te.pos.wp = t->args;
te.isa = dbteste_isa;
te.getopnd = dbteste_getopnd;
te.eval = dbteste_eval;
te.error = dbteste_error;
rv = test_parse(&te);
break;
}
#endif /* KSH */
case TFOR:
#ifdef KSH
case TSELECT:
{
volatile bool is_first = true;
#endif /* KSH */
ap = (t->vars != NULL) ?
eval(t->vars, DOBLANK|DOGLOB|DOTILDE)
: e->loc->argv + 1;
e->type = E_LOOP;
while (1) {
i = ksh_sigsetjmp(e->jbuf, 0);
if (!i)
break;
if ((e->flags&EF_BRKCONT_PASS)
|| (i != LBREAK && i != LCONTIN))
{
quitenv();
unwind(i);
} else if (i == LBREAK) {
rv = 0;
goto Break;
}
}
rv = 0; /* in case of a continue */
if (t->type == TFOR) {
while (*ap != NULL) {
setstr(global(t->str), *ap++, KSH_UNWIND_ERROR);
rv = execute(t->left, flags & XERROK);
}
}
#ifdef KSH
else { /* TSELECT */
for (;;) {
if (!(cp = do_selectargs(ap, is_first))) {
rv = 1;
break;
}
is_first = false;
setstr(global(t->str), cp, KSH_UNWIND_ERROR);
rv = execute(t->left, flags & XERROK);
}
}
}
#endif /* KSH */
break;
case TWHILE:
case TUNTIL:
e->type = E_LOOP;
while (1) {
i = ksh_sigsetjmp(e->jbuf, 0);
if (!i)
break;
if ((e->flags&EF_BRKCONT_PASS)
|| (i != LBREAK && i != LCONTIN))
{
quitenv();
unwind(i);
} else if (i == LBREAK) {
rv = 0;
goto Break;
}
}
rv = 0; /* in case of a continue */
while ((execute(t->left, XERROK) == 0) == (t->type == TWHILE))
rv = execute(t->right, flags & XERROK);
break;
case TIF:
case TELIF:
if (t->right == NULL)
break; /* should be error */
rv = execute(t->left, XERROK) == 0 ?
execute(t->right->left, flags & XERROK) :
execute(t->right->right, flags & XERROK);
break;
case TCASE:
cp = evalstr(t->str, DOTILDE);
for (t = t->left; t != NULL && t->type == TPAT; t = t->right)
for (ap = t->vars; *ap; ap++)
if ((s = evalstr(*ap, DOTILDE|DOPAT))
&& gmatch(cp, s, false))
goto Found;
break;
Found:
rv = execute(t->left, flags & XERROK);
break;
case TBRACE:
rv = execute(t->left, flags & XERROK);
break;
case TFUNCT:
rv = define(t->str, t);
break;
case TTIME:
/* Clear XEXEC so nested execute() call doesn't exit
* (allows "ls -l | time grep foo").
*/
rv = timex(t, flags & ~XEXEC);
break;
case TEXEC: /* an eval'd TCOM */
s = t->args[0];
ap = makenv();
#ifndef F_SETFD
for (i = 0; i < sizeof(clexec_tab); i++)
if (clexec_tab[i]) {
close(i);
clexec_tab[i] = 0;
}
#endif
restoresigs();
cleanup_proc_env();
execve(t->str, t->args, ap);
if (errno == ENOEXEC)
scriptexec(t, ap);
else
errorf("%s: %s", s, strerror(errno));
}
Break:
exstat = rv;
quitenv(); /* restores IO */
if ((flags&XEXEC))
unwind(LEXIT); /* exit child */
if (rv != 0 && !(flags & XERROK)) {
if (Flag(FERREXIT))
unwind(LERROR);
trapsig(SIGERR_);
}
return rv;
}
/*
* execute simple command
*/
static int
comexec(t, tp, ap, flags)
struct op *t;
struct tbl *volatile tp;
register char **ap;
int volatile flags;
{
int i;
int leave = LLEAVE;
volatile int rv = 0;
register char *cp;
register char **lastp;
static struct op texec; /* Must be static (XXX but why?) */
int type_flags;
int keepasn_ok;
int fcflags = FC_BI|FC_FUNC|FC_PATH;
int bourne_function_call = 0;
#ifdef KSH
/* snag the last argument for $_ XXX not the same as at&t ksh,
* which only seems to set $_ after a newline (but not in
* functions/dot scripts, but in interactive and script) -
* perhaps save last arg here and set it in shell()?.
*/
if (Flag(FTALKING) && *(lastp = ap)) {
while (*++lastp)
;
/* setstr() can't fail here */
setstr(typeset("_", LOCAL, 0, INTEGER, 0), *--lastp,
KSH_RETURN_ERROR);
}
#endif /* KSH */
/* Deal with the shell builtins builtin, exec and command since
* they can be followed by other commands. This must be done before
* we know if we should create a local block, which must be done
* before we can do a path search (in case the assignments change
* PATH).
* Odd cases:
* FOO=bar exec > /dev/null FOO is kept but not exported
* FOO=bar exec foobar FOO is exported
* FOO=bar command exec > /dev/null FOO is neither kept nor exported
* FOO=bar command FOO is neither kept nor exported
* PATH=... foobar use new PATH in foobar search
*/
keepasn_ok = 1;
while (tp && tp->type == CSHELL) {
fcflags = FC_BI|FC_FUNC|FC_PATH;/* undo effects of command */
if (tp->val.f == c_builtin) {
if ((cp = *++ap) == NULL) {
tp = NULL;
break;
}
tp = findcom(cp, FC_BI);
if (tp == NULL)
errorf("builtin: %s: not a builtin", cp);
continue;
} else if (tp->val.f == c_exec) {
if (ap[1] == NULL)
break;
ap++;
flags |= XEXEC;
} else if (tp->val.f == c_command) {
int optc, saw_p = 0;
/* Ugly dealing with options in two places (here and
* in c_command(), but such is life)
*/
ksh_getopt_reset(&builtin_opt, 0);
while ((optc = ksh_getopt(ap, &builtin_opt, ":p"))
== 'p')
saw_p = 1;
if (optc != EOF)
break; /* command -vV or something */
/* don't look for functions */
fcflags = FC_BI|FC_PATH;
if (saw_p) {
if (Flag(FRESTRICTED)) {
warningf(true,
"command -p: restricted");
rv = 1;
goto Leave;
}
fcflags |= FC_DEFPATH;
}
ap += builtin_opt.optind;
/* POSIX says special builtins lose their status
* if accessed using command.
*/
keepasn_ok = 0;
if (!ap[0]) {
/* ensure command with no args exits with 0 */
subst_exstat = 0;
break;
}
} else
break;
tp = findcom(ap[0], fcflags & (FC_BI|FC_FUNC));
}
if (keepasn_ok && (!ap[0] || (tp && (tp->flag & KEEPASN))))
type_flags = 0;
else {
/* create new variable/function block */
newblock();
/* ksh functions don't keep assignments, POSIX functions do. */
if (keepasn_ok && tp && tp->type == CFUNC
&& !(tp->flag & FKSH)) {
bourne_function_call = 1;
type_flags = 0;
} else
type_flags = LOCAL|LOCAL_COPY|EXPORT;
}
if (Flag(FEXPORT))
type_flags |= EXPORT;
for (i = 0; t->vars[i]; i++) {
cp = evalstr(t->vars[i], DOASNTILDE);
if (Flag(FXTRACE)) {
if (i == 0)
shf_fprintf(shl_out, "%s",
PS4_SUBSTITUTE(str_val(global("PS4"))));
shf_fprintf(shl_out, "%s%s", cp,
t->vars[i + 1] ? space : newline);
if (!t->vars[i + 1])
shf_flush(shl_out);
}
typeset(cp, type_flags, 0, 0, 0);
if (bourne_function_call && !(type_flags & EXPORT))
typeset(cp, LOCAL|LOCAL_COPY|EXPORT, 0, 0, 0);
}
if ((cp = *ap) == NULL) {
rv = subst_exstat;
goto Leave;
} else if (!tp) {
if (Flag(FRESTRICTED) && ksh_strchr_dirsep(cp)) {
warningf(true, "%s: restricted", cp);
rv = 1;
goto Leave;
}
tp = findcom(cp, fcflags);
}
switch (tp->type) {
case CSHELL: /* shell built-in */
rv = call_builtin(tp, ap);
break;
case CFUNC: /* function call */
{
volatile int old_xflag;
volatile Tflag old_inuse;
const char *volatile old_kshname;
if (!(tp->flag & ISSET)) {
struct tbl *ftp;
if (!tp->u.fpath) {
if (tp->u2.errno_) {
warningf(true,
"%s: can't find function definition file - %s",
cp, strerror(tp->u2.errno_));
rv = 126;
} else {
warningf(true,
"%s: can't find function definition file", cp);
rv = 127;
}
break;
}
if (include(tp->u.fpath, 0, (char **) 0, 0) < 0) {
warningf(true,
"%s: can't open function definition file %s - %s",
cp, tp->u.fpath, strerror(errno));
rv = 127;
break;
}
if (!(ftp = findfunc(cp, hash(cp), false))
|| !(ftp->flag & ISSET))
{
warningf(true,
"%s: function not defined by %s",
cp, tp->u.fpath);
rv = 127;
break;
}
tp = ftp;
}
/* ksh functions set $0 to function name, POSIX functions leave
* $0 unchanged.
*/
old_kshname = kshname;
if (tp->flag & FKSH)
kshname = ap[0];
else
ap[0] = (char *) __UNCONST(kshname);
e->loc->argv = ap;
for (i = 0; *ap++ != NULL; i++)
;
e->loc->argc = i - 1;
/* ksh-style functions handle getopts sanely,
* bourne/posix functions are insane...
*/
if (tp->flag & FKSH) {
e->loc->flags |= BF_DOGETOPTS;
e->loc->getopts_state = user_opt;
getopts_reset(1);
}
old_xflag = Flag(FXTRACE);
Flag(FXTRACE) = tp->flag & TRACE ? true : false;
old_inuse = tp->flag & FINUSE;
tp->flag |= FINUSE;
e->type = E_FUNC;
i = ksh_sigsetjmp(e->jbuf, 0);
if (i == 0) {
/* seems odd to pass XERROK here, but at&t ksh does */
exstat = execute(tp->val.t, flags & XERROK);
i = LRETURN;
}
kshname = old_kshname;
Flag(FXTRACE) = old_xflag;
tp->flag = (tp->flag & ~FINUSE) | old_inuse;
/* Were we deleted while executing? If so, free the execution
* tree. todo: Unfortunately, the table entry is never re-used
* until the lookup table is expanded.
*/
if ((tp->flag & (FDELETE|FINUSE)) == FDELETE) {
if (tp->flag & ALLOC) {
tp->flag &= ~ALLOC;
tfree(tp->val.t, tp->areap);
}
tp->flag = 0;
}
switch (i) {
case LRETURN:
case LERROR:
rv = exstat;
break;
case LINTR:
case LEXIT:
case LLEAVE:
case LSHELL:
quitenv();
unwind(i);
/*NOTREACHED*/
default:
quitenv();
internal_errorf(1, "CFUNC %d", i);
}
break;
}
case CEXEC: /* executable command */
case CTALIAS: /* tracked alias */
if (!(tp->flag&ISSET)) {
/* errno_ will be set if the named command was found
* but could not be executed (permissions, no execute
* bit, directory, etc). Print out a (hopefully)
* useful error message and set the exit status to 126.
*/
if (tp->u2.errno_) {
warningf(true, "%s: cannot execute - %s", cp,
strerror(tp->u2.errno_));
rv = 126; /* POSIX */
} else {
warningf(true, "%s: not found", cp);
rv = 127;
}
break;
}
#ifdef KSH
/* set $_ to program's full path */
/* setstr() can't fail here */
setstr(typeset("_", LOCAL|EXPORT, 0, INTEGER, 0),
tp->val.s, KSH_RETURN_ERROR);
#endif /* KSH */
if (flags&XEXEC) {
j_exit();
if (!(flags&XBGND) || Flag(FMONITOR)) {
setexecsig(&sigtraps[SIGINT], SS_RESTORE_ORIG);
setexecsig(&sigtraps[SIGQUIT], SS_RESTORE_ORIG);
}
}
/* to fork we set up a TEXEC node and call execute */
texec.type = TEXEC;
texec.left = t; /* for tprint */
texec.str = tp->val.s;
texec.args = ap;
rv = exchild(&texec, flags, -1);
break;
}
leave = LEXIT;
Leave:
if (flags & XEXEC) {
exstat = rv;
unwind(leave);
}
return rv;
}
static void
scriptexec(tp, ap)
register struct op *tp;
register char **ap;
{
char *shellv;
shellv = str_val(global(EXECSHELL_STR));
if (shellv && *shellv)
shellv = search(shellv, path, X_OK, (int *) 0);
if (!shellv || !*shellv)
shellv = __UNCONST(EXECSHELL);
*tp->args-- = tp->str;
*tp->args = shellv;
execve(tp->args[0], tp->args, ap);
/* report both the program that was run and the bogus shell */
errorf("%s: %s: %s", tp->str, shellv, strerror(errno));
}
int
shcomexec(wp)
register char **wp;
{
register struct tbl *tp;
tp = tsearch(&builtins, *wp, hash(*wp));
if (tp == NULL)
internal_errorf(1, "shcomexec: %s", *wp);
return call_builtin(tp, wp);
}
/*
* Search function tables for a function. If create set, a table entry
* is created if none is found.
*/
struct tbl *
findfunc(name, h, create)
const char *name;
unsigned int h;
int create;
{
struct block *l;
struct tbl *tp = (struct tbl *) 0;
for (l = e->loc; l; l = l->next) {
tp = tsearch(&l->funs, name, h);
if (tp)
break;
if (!l->next && create) {
tp = tenter(&l->funs, name, h);
tp->flag = DEFINED;
tp->type = CFUNC;
tp->val.t = (struct op *) 0;
break;
}
}
return tp;
}
/*
* define function. Returns 1 if function is being undefined (t == 0) and
* function did not exist, returns 0 otherwise.
*/
int
define(name, t)
const char *name;
struct op *t;
{
struct tbl *tp;
int was_set = 0;
while (1) {
tp = findfunc(name, hash(name), true);
if (tp->flag & ISSET)
was_set = 1;
/* If this function is currently being executed, we zap this
* table entry so findfunc() won't see it
*/
if (tp->flag & FINUSE) {
tp->name[0] = '\0';
tp->flag &= ~DEFINED; /* ensure it won't be found */
tp->flag |= FDELETE;
} else
break;
}
if (tp->flag & ALLOC) {
tp->flag &= ~(ISSET|ALLOC);
tfree(tp->val.t, tp->areap);
}
if (t == NULL) { /* undefine */
tdelete(tp);
return was_set ? 0 : 1;
}
tp->val.t = tcopy(t->left, tp->areap);
tp->flag |= (ISSET|ALLOC);
if (t->u.ksh_func)
tp->flag |= FKSH;
return 0;
}
/*
* add builtin
*/
void
builtin(name, func)
const char *name;
int (*func) ARGS((char **));
{
register struct tbl *tp;
Tflag flag;
/* see if any flags should be set for this builtin */
for (flag = 0; ; name++) {
if (*name == '=') /* command does variable assignment */
flag |= KEEPASN;
else if (*name == '*') /* POSIX special builtin */
flag |= SPEC_BI;
else if (*name == '+') /* POSIX regular builtin */
flag |= REG_BI;
else
break;
}
tp = tenter(&builtins, name, hash(name));
tp->flag = DEFINED | flag;
tp->type = CSHELL;
tp->val.f = func;
}
/*
* find command
* either function, hashed command, or built-in (in that order)
*/
struct tbl *
findcom(name, flags)
const char *name;
int flags; /* FC_* */
{
static struct tbl temp;
unsigned int h = hash(name);
struct tbl *tp = NULL, *tbi;
int insert = Flag(FTRACKALL); /* insert if not found */
char *fpath; /* for function autoloading */
char *npath;
if (ksh_strchr_dirsep(name) != NULL) {
insert = 0;
/* prevent FPATH search below */
flags &= ~FC_FUNC;
goto Search;
}
tbi = (flags & FC_BI) ? tsearch(&builtins, name, h) : NULL;
/* POSIX says special builtins first, then functions, then
* POSIX regular builtins, then search path...
*/
if ((flags & FC_SPECBI) && tbi && (tbi->flag & SPEC_BI))
tp = tbi;
if (!tp && (flags & FC_FUNC)) {
tp = findfunc(name, h, false);
if (tp && !(tp->flag & ISSET)) {
if ((fpath = str_val(global("FPATH"))) == null) {
tp->u.fpath = (char *) 0;
tp->u2.errno_ = 0;
} else
tp->u.fpath = search(name, fpath, R_OK,
&tp->u2.errno_);
}
}
if (!tp && (flags & FC_REGBI) && tbi && (tbi->flag & REG_BI))
tp = tbi;
/* todo: posix says non-special/non-regular builtins must
* be triggered by some user-controllable means like a
* special directory in PATH. Requires modifications to
* the search() function. Tracked aliases should be
* modified to allow tracking of builtin commands.
* This should be under control of the FPOSIX flag.
* If this is changed, also change c_whence...
*/
if (!tp && (flags & FC_UNREGBI) && tbi)
tp = tbi;
if (!tp && (flags & FC_PATH) && !(flags & FC_DEFPATH)) {
tp = tsearch(&taliases, name, h);
if (tp && (tp->flag & ISSET) && eaccess(tp->val.s, X_OK) != 0) {
if (tp->flag & ALLOC) {
tp->flag &= ~ALLOC;
afree(tp->val.s, APERM);
}
tp->flag &= ~ISSET;
}
}
Search:
if ((!tp || (tp->type == CTALIAS && !(tp->flag&ISSET)))
&& (flags & FC_PATH))
{
if (!tp) {
if (insert && !(flags & FC_DEFPATH)) {
tp = tenter(&taliases, name, h);
tp->type = CTALIAS;
} else {
tp = &temp;
tp->type = CEXEC;
}
tp->flag = DEFINED; /* make ~ISSET */
}
npath = search(name, flags & FC_DEFPATH ? def_path : path,
X_OK, &tp->u2.errno_);
if (npath) {
if (tp == &temp) {
tp->val.s = npath;
} else {
tp->val.s = str_save(npath, APERM);
afree(npath, ATEMP);
}
tp->flag |= ISSET|ALLOC;
} else if ((flags & FC_FUNC)
&& (fpath = str_val(global("FPATH"))) != null
&& (npath = search(name, fpath, R_OK,
&tp->u2.errno_)) != (char *) 0)
{
/* An undocumented feature of at&t ksh is that it
* searches FPATH if a command is not found, even
* if the command hasn't been set up as an autoloaded
* function (ie, no typeset -uf).
*/
tp = &temp;
tp->type = CFUNC;
tp->flag = DEFINED; /* make ~ISSET */
tp->u.fpath = npath;
}
}
return tp;
}
/*
* flush executable commands with relative paths
*/
void
flushcom(all)
int all; /* just relative or all */
{
struct tbl *tp;
struct tstate ts;