freebsd-dev/contrib/tcsh/sh.exec.c
2007-03-11 22:33:41 +00:00

1172 lines
28 KiB
C

/* $Header: /p/tcsh/cvsroot/tcsh/sh.exec.c,v 3.73 2006/08/24 20:56:31 christos Exp $ */
/*
* sh.exec.c: Search, find, and execute a command!
*/
/*-
* Copyright (c) 1980, 1991 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include "sh.h"
RCSID("$tcsh: sh.exec.c,v 3.73 2006/08/24 20:56:31 christos Exp $")
#include "tc.h"
#include "tw.h"
#ifdef WINNT_NATIVE
#include <nt.const.h>
#endif /*WINNT_NATIVE*/
/*
* C shell
*/
#ifndef OLDHASH
# define FASTHASH /* Fast hashing is the default */
#endif /* OLDHASH */
/*
* System level search and execute of a command.
* We look in each directory for the specified command name.
* If the name contains a '/' then we execute only the full path name.
* If there is no search path then we execute only full path names.
*/
/*
* As we search for the command we note the first non-trivial error
* message for presentation to the user. This allows us often
* to show that a file has the wrong mode/no access when the file
* is not in the last component of the search path, so we must
* go on after first detecting the error.
*/
static char *exerr; /* Execution error message */
static Char *expath; /* Path for exerr */
/*
* The two part hash function is designed to let texec() call the
* more expensive hashname() only once and the simple hash() several
* times (once for each path component checked).
* Byte size is assumed to be 8.
*/
#define BITS_PER_BYTE 8
#ifdef FASTHASH
/*
* xhash is an array of hash buckets which are used to hash execs. If
* it is allocated (havhash true), then to tell if ``name'' is
* (possibly) presend in the i'th component of the variable path, look
* at the [hashname(name)] bucket of size [hashwidth] bytes, in the [i
* mod size*8]'th bit. The cache size is defaults to a length of 1024
* buckets, each 1 byte wide. This implementation guarantees that
* objects n bytes wide will be aligned on n byte boundaries.
*/
# define HSHMUL 241
static unsigned long *xhash = NULL;
static unsigned int hashlength = 0, uhashlength = 0;
static unsigned int hashwidth = 0, uhashwidth = 0;
static int hashdebug = 0;
# define hash(a, b) (((a) * HSHMUL + (b)) % (hashlength))
# define widthof(t) (sizeof(t) * BITS_PER_BYTE)
# define tbit(f, i, t) (((t *) xhash)[(f)] & \
(1UL << (i & (widthof(t) - 1))))
# define tbis(f, i, t) (((t *) xhash)[(f)] |= \
(1UL << (i & (widthof(t) - 1))))
# define cbit(f, i) tbit(f, i, unsigned char)
# define cbis(f, i) tbis(f, i, unsigned char)
# define sbit(f, i) tbit(f, i, unsigned short)
# define sbis(f, i) tbis(f, i, unsigned short)
# define ibit(f, i) tbit(f, i, unsigned int)
# define ibis(f, i) tbis(f, i, unsigned int)
# define lbit(f, i) tbit(f, i, unsigned long)
# define lbis(f, i) tbis(f, i, unsigned long)
# define bit(f, i) (hashwidth==sizeof(unsigned char) ? cbit(f,i) : \
((hashwidth==sizeof(unsigned short) ? sbit(f,i) : \
((hashwidth==sizeof(unsigned int) ? ibit(f,i) : \
lbit(f,i))))))
# define bis(f, i) (hashwidth==sizeof(unsigned char) ? cbis(f,i) : \
((hashwidth==sizeof(unsigned short) ? sbis(f,i) : \
((hashwidth==sizeof(unsigned int) ? ibis(f,i) : \
lbis(f,i))))))
#else /* OLDHASH */
/*
* Xhash is an array of HSHSIZ bits (HSHSIZ / 8 chars), which are used
* to hash execs. If it is allocated (havhash true), then to tell
* whether ``name'' is (possibly) present in the i'th component
* of the variable path, you look at the bit in xhash indexed by
* hash(hashname("name"), i). This is setup automatically
* after .login is executed, and recomputed whenever ``path'' is
* changed.
*/
# define HSHSIZ 8192 /* 1k bytes */
# define HSHMASK (HSHSIZ - 1)
# define HSHMUL 243
static char xhash[HSHSIZ / BITS_PER_BYTE];
# define hash(a, b) (((a) * HSHMUL + (b)) & HSHMASK)
# define bit(h, b) ((h)[(b) >> 3] & 1 << ((b) & 7)) /* bit test */
# define bis(h, b) ((h)[(b) >> 3] |= 1 << ((b) & 7)) /* bit set */
#endif /* FASTHASH */
#ifdef VFORK
static int hits, misses;
#endif /* VFORK */
/* Dummy search path for just absolute search when no path */
static Char *justabs[] = {STRNULL, 0};
static void pexerr (void);
static void texec (Char *, Char **);
int hashname (Char *);
static int iscommand (Char *);
void
doexec(struct command *t, int do_glob)
{
Char *dp, **pv, **av, *sav;
struct varent *v;
int slash, gflag;
int hashval, i;
Char *blk[2];
/*
* Glob the command name. We will search $path even if this does something,
* as in sh but not in csh. One special case: if there is no PATH, then we
* execute only commands which start with '/'.
*/
blk[0] = t->t_dcom[0];
blk[1] = 0;
gflag = 0;
if (do_glob)
gflag = tglob(blk);
if (gflag) {
pv = globall(blk, gflag);
if (pv == 0) {
setname(short2str(blk[0]));
stderror(ERR_NAME | ERR_NOMATCH);
}
}
else
pv = saveblk(blk);
cleanup_push(pv, blk_cleanup);
trim(pv);
exerr = 0;
expath = Strsave(pv[0]);
#ifdef VFORK
Vexpath = expath;
#endif /* VFORK */
v = adrof(STRpath);
if (v == 0 && expath[0] != '/' && expath[0] != '.')
pexerr();
slash = any(short2str(expath), '/');
/*
* Glob the argument list, if necessary. Otherwise trim off the quote bits.
*/
gflag = 0;
av = &t->t_dcom[1];
if (do_glob)
gflag = tglob(av);
if (gflag) {
av = globall(av, gflag);
if (av == 0) {
setname(short2str(expath));
stderror(ERR_NAME | ERR_NOMATCH);
}
}
else
av = saveblk(av);
blkfree(t->t_dcom);
cleanup_ignore(pv);
cleanup_until(pv);
t->t_dcom = blkspl(pv, av);
xfree(pv);
xfree(av);
av = t->t_dcom;
trim(av);
if (*av == NULL || **av == '\0')
pexerr();
xechoit(av); /* Echo command if -x */
#ifdef CLOSE_ON_EXEC
/*
* Since all internal file descriptors are set to close on exec, we don't
* need to close them explicitly here. Just reorient ourselves for error
* messages.
*/
SHIN = 0;
SHOUT = 1;
SHDIAG = 2;
OLDSTD = 0;
isoutatty = isatty(SHOUT);
isdiagatty = isatty(SHDIAG);
#else
closech(); /* Close random fd's */
#endif
/*
* We must do this AFTER any possible forking (like `foo` in glob) so that
* this shell can still do subprocesses.
*/
{
sigset_t set;
sigemptyset(&set);
sigaddset(&set, SIGINT);
sigaddset(&set, SIGCHLD);
sigprocmask(SIG_UNBLOCK, &set, NULL);
}
pintr_disabled = 0;
pchild_disabled = 0;
/*
* If no path, no words in path, or a / in the filename then restrict the
* command search.
*/
if (v == NULL || v->vec == NULL || v->vec[0] == NULL || slash)
pv = justabs;
else
pv = v->vec;
sav = Strspl(STRslash, *av);/* / command name for postpending */
#ifndef VFORK
cleanup_push(sav, xfree);
#else /* VFORK */
Vsav = sav;
#endif /* VFORK */
hashval = havhash ? hashname(*av) : 0;
i = 0;
#ifdef VFORK
hits++;
#endif /* VFORK */
do {
/*
* Try to save time by looking at the hash table for where this command
* could be. If we are doing delayed hashing, then we put the names in
* one at a time, as the user enters them. This is kinda like Korn
* Shell's "tracked aliases".
*/
if (!slash && ABSOLUTEP(pv[0]) && havhash) {
#ifdef FASTHASH
if (!bit(hashval, i))
goto cont;
#else /* OLDHASH */
int hashval1 = hash(hashval, i);
if (!bit(xhash, hashval1))
goto cont;
#endif /* FASTHASH */
}
if (pv[0][0] == 0 || eq(pv[0], STRdot)) /* don't make ./xxx */
texec(*av, av);
else {
dp = Strspl(*pv, sav);
#ifndef VFORK
cleanup_push(dp, xfree);
#else /* VFORK */
Vdp = dp;
#endif /* VFORK */
texec(dp, av);
#ifndef VFORK
cleanup_until(dp);
#else /* VFORK */
Vdp = 0;
xfree(dp);
#endif /* VFORK */
}
#ifdef VFORK
misses++;
#endif /* VFORK */
cont:
pv++;
i++;
} while (*pv);
#ifdef VFORK
hits--;
#endif /* VFORK */
#ifndef VFORK
cleanup_until(sav);
#else /* VFORK */
Vsav = 0;
xfree(sav);
#endif /* VFORK */
pexerr();
}
static void
pexerr(void)
{
/* Couldn't find the damn thing */
if (expath) {
setname(short2str(expath));
#ifdef VFORK
Vexpath = 0;
#endif /* VFORK */
xfree(expath);
expath = 0;
}
else
setname("");
if (exerr)
stderror(ERR_NAME | ERR_STRING, exerr);
stderror(ERR_NAME | ERR_COMMAND);
}
/*
* Execute command f, arg list t.
* Record error message if not found.
* Also do shell scripts here.
*/
static void
texec(Char *sf, Char **st)
{
char **t;
char *f;
struct varent *v;
Char **vp;
Char *lastsh[2];
char pref[2];
int fd;
Char *st0, **ost;
/* The order for the conversions is significant */
t = short2blk(st);
f = short2str(sf);
#ifdef VFORK
Vt = t;
#endif /* VFORK */
errno = 0; /* don't use a previous error */
#ifdef apollo
/*
* If we try to execute an nfs mounted directory on the apollo, we
* hang forever. So until apollo fixes that..
*/
{
struct stat stb;
if (stat(f, &stb) == 0 && S_ISDIR(stb.st_mode))
errno = EISDIR;
}
if (errno == 0)
#endif /* apollo */
{
#ifdef ISC_POSIX_EXEC_BUG
__setostype(0); /* "0" is "__OS_SYSV" in <sys/user.h> */
#endif /* ISC_POSIX_EXEC_BUG */
(void) execv(f, t);
#ifdef ISC_POSIX_EXEC_BUG
__setostype(1); /* "1" is "__OS_POSIX" in <sys/user.h> */
#endif /* ISC_POSIX_EXEC_BUG */
}
#ifdef VFORK
Vt = 0;
#endif /* VFORK */
blkfree((Char **) t);
switch (errno) {
case ENOEXEC:
#ifdef WINNT_NATIVE
nt_feed_to_cmd(f,t);
#endif /* WINNT_NATIVE */
/*
* From: casper@fwi.uva.nl (Casper H.S. Dik) If we could not execute
* it, don't feed it to the shell if it looks like a binary!
*/
if ((fd = xopen(f, O_RDONLY|O_LARGEFILE)) != -1) {
int nread;
#ifdef O_TEXT
setmode(fd, O_TEXT);
#endif
if ((nread = xread(fd, pref, 2)) == 2) {
if (!isprint((unsigned char)pref[0]) &&
(pref[0] != '\n' && pref[0] != '\t')) {
int err;
err = errno;
xclose(fd);
/*
* We *know* what ENOEXEC means.
*/
stderror(ERR_ARCH, f, strerror(err));
}
}
else if (nread < 0) {
#ifdef convex
int err;
err = errno;
xclose(fd);
/* need to print error incase the file is migrated */
stderror(ERR_SYSTEM, f, strerror(err));
#endif
}
#ifdef _PATH_BSHELL
else {
pref[0] = '#';
pref[1] = '\0';
}
#endif
}
#ifdef HASHBANG
if (fd == -1 ||
pref[0] != '#' || pref[1] != '!' || hashbang(fd, &vp) == -1) {
#endif /* HASHBANG */
/*
* If there is an alias for shell, then put the words of the alias in
* front of the argument list replacing the command name. Note no
* interpretation of the words at this point.
*/
v = adrof1(STRshell, &aliases);
if (v == NULL || v->vec == NULL) {
vp = lastsh;
vp[0] = adrof(STRshell) ? varval(STRshell) : STR_SHELLPATH;
vp[1] = NULL;
#ifdef _PATH_BSHELL
if (fd != -1
# ifndef ISC /* Compatible with ISC's /bin/csh */
&& pref[0] != '#'
# endif /* ISC */
)
vp[0] = STR_BSHELL;
#endif
vp = saveblk(vp);
}
else
vp = saveblk(v->vec);
#ifdef HASHBANG
}
#endif /* HASHBANG */
if (fd != -1)
xclose(fd);
st0 = st[0];
st[0] = sf;
ost = st;
st = blkspl(vp, st); /* Splice up the new arglst */
ost[0] = st0;
sf = *st;
/* The order for the conversions is significant */
t = short2blk(st);
f = short2str(sf);
xfree(st);
blkfree((Char **) vp);
#ifdef VFORK
Vt = t;
#endif /* VFORK */
#ifdef ISC_POSIX_EXEC_BUG
__setostype(0); /* "0" is "__OS_SYSV" in <sys/user.h> */
#endif /* ISC_POSIX_EXEC_BUG */
(void) execv(f, t);
#ifdef ISC_POSIX_EXEC_BUG
__setostype(1); /* "1" is "__OS_POSIX" in <sys/user.h> */
#endif /* ISC_POSIX_EXEC_BUG */
#ifdef VFORK
Vt = 0;
#endif /* VFORK */
blkfree((Char **) t);
/* The sky is falling, the sky is falling! */
stderror(ERR_SYSTEM, f, strerror(errno));
break;
case ENOMEM:
stderror(ERR_SYSTEM, f, strerror(errno));
break;
#ifdef _IBMR2
case 0: /* execv fails and returns 0! */
#endif /* _IBMR2 */
case ENOENT:
break;
default:
if (exerr == 0) {
exerr = strerror(errno);
xfree(expath);
expath = Strsave(sf);
#ifdef VFORK
Vexpath = expath;
#endif /* VFORK */
}
break;
}
}
struct execash_state
{
int saveIN, saveOUT, saveDIAG, saveSTD;
int SHIN, SHOUT, SHDIAG, OLDSTD;
int didfds;
#ifndef CLOSE_ON_EXEC
int didcch;
#endif
struct sigaction sigint, sigquit, sigterm;
};
static void
execash_cleanup(void *xstate)
{
struct execash_state *state;
state = xstate;
sigaction(SIGINT, &state->sigint, NULL);
sigaction(SIGQUIT, &state->sigquit, NULL);
sigaction(SIGTERM, &state->sigterm, NULL);
doneinp = 0;
#ifndef CLOSE_ON_EXEC
didcch = state->didcch;
#endif /* CLOSE_ON_EXEC */
didfds = state->didfds;
xclose(SHIN);
xclose(SHOUT);
xclose(SHDIAG);
xclose(OLDSTD);
close_on_exec(SHIN = dmove(state->saveIN, state->SHIN), 1);
close_on_exec(SHOUT = dmove(state->saveOUT, state->SHOUT), 1);
close_on_exec(SHDIAG = dmove(state->saveDIAG, state->SHDIAG), 1);
close_on_exec(OLDSTD = dmove(state->saveSTD, state->OLDSTD), 1);
}
/*ARGSUSED*/
void
execash(Char **t, struct command *kp)
{
struct execash_state state;
USE(t);
if (chkstop == 0 && setintr)
panystop(0);
/*
* Hmm, we don't really want to do that now because we might
* fail, but what is the choice
*/
rechist(NULL, adrof(STRsavehist) != NULL);
sigaction(SIGINT, &parintr, &state.sigint);
sigaction(SIGQUIT, &parintr, &state.sigquit);
sigaction(SIGTERM, &parterm, &state.sigterm);
state.didfds = didfds;
#ifndef CLOSE_ON_EXEC
state.didcch = didcch;
#endif /* CLOSE_ON_EXEC */
state.SHIN = SHIN;
state.SHOUT = SHOUT;
state.SHDIAG = SHDIAG;
state.OLDSTD = OLDSTD;
(void)close_on_exec (state.saveIN = dcopy(SHIN, -1), 1);
(void)close_on_exec (state.saveOUT = dcopy(SHOUT, -1), 1);
(void)close_on_exec (state.saveDIAG = dcopy(SHDIAG, -1), 1);
(void)close_on_exec (state.saveSTD = dcopy(OLDSTD, -1), 1);
lshift(kp->t_dcom, 1);
(void)close_on_exec (SHIN = dcopy(0, -1), 1);
(void)close_on_exec (SHOUT = dcopy(1, -1), 1);
(void)close_on_exec (SHDIAG = dcopy(2, -1), 1);
#ifndef CLOSE_ON_EXEC
didcch = 0;
#endif /* CLOSE_ON_EXEC */
didfds = 0;
cleanup_push(&state, execash_cleanup);
/*
* Decrement the shell level
*/
shlvl(-1);
#ifdef WINNT_NATIVE
__nt_really_exec=1;
#endif /* WINNT_NATIVE */
doexec(kp, 1);
cleanup_until(&state);
}
void
xechoit(Char **t)
{
if (adrof(STRecho)) {
int odidfds = didfds;
flush();
haderr = 1;
didfds = 0;
blkpr(t), xputchar('\n');
flush();
didfds = odidfds;
haderr = 0;
}
}
/*ARGSUSED*/
void
dohash(Char **vv, struct command *c)
{
#ifdef COMMENT
struct stat stb;
#endif
DIR *dirp;
struct dirent *dp;
int i = 0;
struct varent *v = adrof(STRpath);
Char **pv;
int hashval;
#ifdef WINNT_NATIVE
int is_windir; /* check if it is the windows directory */
USE(hashval);
#endif /* WINNT_NATIVE */
USE(c);
#ifdef FASTHASH
if (vv && vv[1]) {
uhashlength = atoi(short2str(vv[1]));
if (vv[2]) {
uhashwidth = atoi(short2str(vv[2]));
if ((uhashwidth != sizeof(unsigned char)) &&
(uhashwidth != sizeof(unsigned short)) &&
(uhashwidth != sizeof(unsigned long)))
uhashwidth = 0;
if (vv[3])
hashdebug = atoi(short2str(vv[3]));
}
}
if (uhashwidth)
hashwidth = uhashwidth;
else {
hashwidth = 0;
if (v == NULL)
return;
for (pv = v->vec; pv && *pv; pv++, hashwidth++)
continue;
if (hashwidth <= widthof(unsigned char))
hashwidth = sizeof(unsigned char);
else if (hashwidth <= widthof(unsigned short))
hashwidth = sizeof(unsigned short);
else if (hashwidth <= widthof(unsigned int))
hashwidth = sizeof(unsigned int);
else
hashwidth = sizeof(unsigned long);
}
if (uhashlength)
hashlength = uhashlength;
else
hashlength = hashwidth * (8*64);/* "average" files per dir in path */
xfree(xhash);
xhash = xcalloc(hashlength * hashwidth, 1);
#endif /* FASTHASH */
(void) getusername(NULL); /* flush the tilde cashe */
tw_cmd_free();
havhash = 1;
if (v == NULL)
return;
for (pv = v->vec; pv && *pv; pv++, i++) {
if (!ABSOLUTEP(pv[0]))
continue;
dirp = opendir(short2str(*pv));
if (dirp == NULL)
continue;
cleanup_push(dirp, opendir_cleanup);
#ifdef COMMENT /* this isn't needed. opendir won't open
* non-dirs */
if (fstat(dirp->dd_fd, &stb) < 0 || !S_ISDIR(stb.st_mode)) {
cleanup_until(dirp);
continue;
}
#endif
#ifdef WINNT_NATIVE
is_windir = nt_check_if_windir(short2str(*pv));
#endif /* WINNT_NATIVE */
while ((dp = readdir(dirp)) != NULL) {
if (dp->d_ino == 0)
continue;
if (dp->d_name[0] == '.' &&
(dp->d_name[1] == '\0' ||
(dp->d_name[1] == '.' && dp->d_name[2] == '\0')))
continue;
#ifdef WINNT_NATIVE
nt_check_name_and_hash(is_windir, dp->d_name, i);
#else /* !WINNT_NATIVE*/
#if defined(_UWIN) || defined(__CYGWIN__)
/* Turn foo.{exe,com,bat} into foo since UWIN's readdir returns
* the file with the .exe, .com, .bat extension
*/
{
ssize_t ext = strlen(dp->d_name) - 4;
if ((ext > 0) && (strcasecmp(&dp->d_name[ext], ".exe") == 0 ||
strcasecmp(&dp->d_name[ext], ".bat") == 0 ||
strcasecmp(&dp->d_name[ext], ".com") == 0)) {
#ifdef __CYGWIN__
/* Also store the variation with extension. */
hashval = hashname(str2short(dp->d_name));
bis(hashval, i);
#endif /* __CYGWIN__ */
dp->d_name[ext] = '\0';
}
}
#endif /* _UWIN || __CYGWIN__ */
# ifdef FASTHASH
hashval = hashname(str2short(dp->d_name));
bis(hashval, i);
if (hashdebug & 1)
xprintf(CGETS(13, 1, "hash=%-4d dir=%-2d prog=%s\n"),
hashname(str2short(dp->d_name)), i, dp->d_name);
# else /* OLD HASH */
hashval = hash(hashname(str2short(dp->d_name)), i);
bis(xhash, hashval);
# endif /* FASTHASH */
/* tw_add_comm_name (dp->d_name); */
#endif /* WINNT_NATIVE */
}
cleanup_until(dirp);
}
}
/*ARGSUSED*/
void
dounhash(Char **v, struct command *c)
{
USE(c);
USE(v);
havhash = 0;
#ifdef FASTHASH
xfree(xhash);
xhash = NULL;
#endif /* FASTHASH */
}
/*ARGSUSED*/
void
hashstat(Char **v, struct command *c)
{
USE(c);
USE(v);
#ifdef FASTHASH
if (havhash && hashlength && hashwidth)
xprintf(CGETS(13, 2, "%d hash buckets of %d bits each\n"),
hashlength, hashwidth*8);
if (hashdebug)
xprintf(CGETS(13, 3, "debug mask = 0x%08x\n"), hashdebug);
#endif /* FASTHASH */
#ifdef VFORK
if (hits + misses)
xprintf(CGETS(13, 4, "%d hits, %d misses, %d%%\n"),
hits, misses, 100 * hits / (hits + misses));
#endif
}
/*
* Hash a command name.
*/
int
hashname(Char *cp)
{
unsigned long h;
for (h = 0; *cp; cp++)
h = hash(h, *cp);
return ((int) h);
}
static int
iscommand(Char *name)
{
Char **pv;
Char *sav;
struct varent *v;
int slash = any(short2str(name), '/');
int hashval, i;
v = adrof(STRpath);
if (v == NULL || v->vec == NULL || v->vec[0] == NULL || slash)
pv = justabs;
else
pv = v->vec;
sav = Strspl(STRslash, name); /* / command name for postpending */
hashval = havhash ? hashname(name) : 0;
i = 0;
do {
if (!slash && ABSOLUTEP(pv[0]) && havhash) {
#ifdef FASTHASH
if (!bit(hashval, i))
goto cont;
#else /* OLDHASH */
int hashval1 = hash(hashval, i);
if (!bit(xhash, hashval1))
goto cont;
#endif /* FASTHASH */
}
if (pv[0][0] == 0 || eq(pv[0], STRdot)) { /* don't make ./xxx */
if (executable(NULL, name, 0)) {
xfree(sav);
return i + 1;
}
}
else {
if (executable(*pv, sav, 0)) {
xfree(sav);
return i + 1;
}
}
cont:
pv++;
i++;
} while (*pv);
xfree(sav);
return 0;
}
/* Also by:
* Andreas Luik <luik@isaak.isa.de>
* I S A GmbH - Informationssysteme fuer computerintegrierte Automatisierung
* Azenberstr. 35
* D-7000 Stuttgart 1
* West-Germany
* is the executable() routine below and changes to iscommand().
* Thanks again!!
*/
#ifndef WINNT_NATIVE
/*
* executable() examines the pathname obtained by concatenating dir and name
* (dir may be NULL), and returns 1 either if it is executable by us, or
* if dir_ok is set and the pathname refers to a directory.
* This is a bit kludgy, but in the name of optimization...
*/
int
executable(const Char *dir, const Char *name, int dir_ok)
{
struct stat stbuf;
char *strname;
if (dir && *dir) {
Char *path;
path = Strspl(dir, name);
strname = short2str(path);
xfree(path);
}
else
strname = short2str(name);
return (stat(strname, &stbuf) != -1 &&
((dir_ok && S_ISDIR(stbuf.st_mode)) ||
(S_ISREG(stbuf.st_mode) &&
/* save time by not calling access() in the hopeless case */
(stbuf.st_mode & (S_IXOTH | S_IXGRP | S_IXUSR)) &&
access(strname, X_OK) == 0
)));
}
#endif /*!WINNT_NATIVE*/
struct tellmewhat_s0_cleanup
{
Char **dest, *val;
};
static void
tellmewhat_s0_cleanup(void *xstate)
{
struct tellmewhat_s0_cleanup *state;
state = xstate;
*state->dest = state->val;
}
int
tellmewhat(struct wordent *lexp, Char **str)
{
struct tellmewhat_s0_cleanup s0;
int i;
const struct biltins *bptr;
struct wordent *sp = lexp->next;
int aliased = 0, found;
Char *s1, *s2, *cmd;
Char qc;
if (adrof1(sp->word, &aliases)) {
alias(lexp);
sp = lexp->next;
aliased = 1;
}
s0.dest = &sp->word; /* to get the memory freeing right... */
s0.val = sp->word;
cleanup_push(&s0, tellmewhat_s0_cleanup);
/* handle quoted alias hack */
if ((*(sp->word) & (QUOTE | TRIM)) == QUOTE)
(sp->word)++;
/* do quoting, if it hasn't been done */
s1 = s2 = sp->word;
while (*s2)
switch (*s2) {
case '\'':
case '"':
qc = *s2++;
while (*s2 && *s2 != qc)
*s1++ = *s2++ | QUOTE;
if (*s2)
s2++;
break;
case '\\':
if (*++s2)
*s1++ = *s2++ | QUOTE;
break;
default:
*s1++ = *s2++;
}
*s1 = '\0';
for (bptr = bfunc; bptr < &bfunc[nbfunc]; bptr++) {
if (eq(sp->word, str2short(bptr->bname))) {
if (str == NULL) {
if (aliased)
prlex(lexp);
xprintf(CGETS(13, 5, "%S: shell built-in command.\n"),
sp->word);
flush();
}
else
*str = Strsave(sp->word);
cleanup_until(&s0);
return TRUE;
}
}
#ifdef WINNT_NATIVE
for (bptr = nt_bfunc; bptr < &nt_bfunc[nt_nbfunc]; bptr++) {
if (eq(sp->word, str2short(bptr->bname))) {
if (str == NULL) {
if (aliased)
prlex(lexp);
xprintf(CGETS(13, 5, "%S: shell built-in command.\n"),
sp->word);
flush();
}
else
*str = Strsave(sp->word);
cleanup_until(&s0);
return TRUE;
}
}
#endif /* WINNT_NATIVE*/
sp->word = cmd = globone(sp->word, G_IGNORE);
cleanup_push(cmd, xfree);
if ((i = iscommand(sp->word)) != 0) {
Char **pv;
struct varent *v;
int slash = any(short2str(sp->word), '/');
v = adrof(STRpath);
if (v == NULL || v->vec == NULL || v->vec[0] == NULL || slash)
pv = justabs;
else
pv = v->vec;
pv += i - 1;
if (pv[0][0] == 0 || eq(pv[0], STRdot)) {
if (!slash) {
sp->word = Strspl(STRdotsl, sp->word);
cleanup_push(sp->word, xfree);
prlex(lexp);
cleanup_until(sp->word);
}
else
prlex(lexp);
}
else {
s1 = Strspl(*pv, STRslash);
sp->word = Strspl(s1, sp->word);
xfree(s1);
cleanup_push(sp->word, xfree);
if (str == NULL)
prlex(lexp);
else
*str = Strsave(sp->word);
cleanup_until(sp->word);
}
found = 1;
}
else {
if (str == NULL) {
if (aliased)
prlex(lexp);
xprintf(CGETS(13, 6, "%S: Command not found.\n"), sp->word);
flush();
}
else
*str = Strsave(sp->word);
found = 0;
}
cleanup_until(&s0);
return found;
}
/*
* Builtin to look at and list all places a command may be defined:
* aliases, shell builtins, and the path.
*
* Marc Horowitz <marc@mit.edu>
* MIT Student Information Processing Board
*/
/*ARGSUSED*/
void
dowhere(Char **v, struct command *c)
{
int found = 1;
USE(c);
for (v++; *v; v++)
found &= find_cmd(*v, 1);
/* Make status nonzero if any command is not found. */
if (!found)
setcopy(STRstatus, STR1, VAR_READWRITE);
}
int
find_cmd(Char *cmd, int prt)
{
struct varent *var;
const struct biltins *bptr;
Char **pv;
Char *sv;
int hashval, i, ex, rval = 0;
if (prt && any(short2str(cmd), '/')) {
xprintf(CGETS(13, 7, "where: / in command makes no sense\n"));
return rval;
}
/* first, look for an alias */
if (prt && adrof1(cmd, &aliases)) {
if ((var = adrof1(cmd, &aliases)) != NULL) {
xprintf(CGETS(13, 8, "%S is aliased to "), cmd);
if (var->vec != NULL)
blkpr(var->vec);
xputchar('\n');
rval = 1;
}
}
/* next, look for a shell builtin */
for (bptr = bfunc; bptr < &bfunc[nbfunc]; bptr++) {
if (eq(cmd, str2short(bptr->bname))) {
rval = 1;
if (prt)
xprintf(CGETS(13, 9, "%S is a shell built-in\n"), cmd);
else
return rval;
}
}
#ifdef WINNT_NATIVE
for (bptr = nt_bfunc; bptr < &nt_bfunc[nt_nbfunc]; bptr++) {
if (eq(cmd, str2short(bptr->bname))) {
rval = 1;
if (prt)
xprintf(CGETS(13, 9, "%S is a shell built-in\n"), cmd);
else
return rval;
}
}
#endif /* WINNT_NATIVE*/
/* last, look through the path for the command */
if ((var = adrof(STRpath)) == NULL)
return rval;
hashval = havhash ? hashname(cmd) : 0;
sv = Strspl(STRslash, cmd);
cleanup_push(sv, xfree);
for (pv = var->vec, i = 0; pv && *pv; pv++, i++) {
if (havhash && !eq(*pv, STRdot)) {
#ifdef FASTHASH
if (!bit(hashval, i))
continue;
#else /* OLDHASH */
int hashval1 = hash(hashval, i);
if (!bit(xhash, hashval1))
continue;
#endif /* FASTHASH */
}
ex = executable(*pv, sv, 0);
#ifdef FASTHASH
if (!ex && (hashdebug & 2)) {
xprintf(CGETS(13, 10, "hash miss: "));
ex = 1; /* Force printing */
}
#endif /* FASTHASH */
if (ex) {
rval = 1;
if (prt) {
xprintf("%S/", *pv);
xprintf("%S\n", cmd);
}
else
return rval;
}
}
cleanup_until(sv);
return rval;
}
#ifdef WINNT_NATIVE
int hashval_extern(cp)
Char *cp;
{
return havhash?hashname(cp):0;
}
int bit_extern(val,i)
int val;
int i;
{
return bit(val,i);
}
void bis_extern(val,i)
int val;
int i;
{
bis(val,i);
}
#endif /* WINNT_NATIVE */