/* $NetBSD: redir.c,v 1.72 2021/11/22 05:17:43 kre Exp $ */
/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* 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 <sys/cdefs.h>
#ifndef lint
#if 0
static char sccsid[] = "@(#)redir.c 8.2 (Berkeley) 5/4/95";
#else
__RCSID("$NetBSD: redir.c,v 1.72 2021/11/22 05:17:43 kre Exp $");
#endif
#endif /* not lint */
#include <sys/types.h>
#include <sys/param.h> /* PIPE_BUF */
#include <sys/stat.h>
#include <signal.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
/*
* Code for dealing with input/output redirection.
*/
#include "main.h"
#include "builtins.h"
#include "shell.h"
#include "nodes.h"
#include "jobs.h"
#include "options.h"
#include "expand.h"
#include "redir.h"
#include "output.h"
#include "memalloc.h"
#include "mystring.h"
#include "error.h"
#include "show.h"
#define EMPTY -2 /* marks an unused slot in redirtab */
#define CLOSED -1 /* fd was not open before redir */
#ifndef PIPE_BUF
# define PIPESIZE 4096 /* amount of buffering in a pipe */
#else
# define PIPESIZE PIPE_BUF
#endif
#ifndef FD_CLOEXEC
# define FD_CLOEXEC 1 /* well known from before there was a name */
#endif
#ifndef F_DUPFD_CLOEXEC
#define F_DUPFD_CLOEXEC F_DUPFD
#define CLOEXEC(fd) (fcntl((fd), F_SETFD, fcntl((fd),F_GETFD) | FD_CLOEXEC))
#else
#define CLOEXEC(fd)
#endif
MKINIT
struct renamelist {
struct renamelist *next;
int orig;
int into;
};
MKINIT
struct redirtab {
struct redirtab *next;
struct renamelist *renamed;
};
MKINIT struct redirtab *redirlist;
/*
* We keep track of whether or not fd0 has been redirected. This is for
* background commands, where we want to redirect fd0 to /dev/null only
* if it hasn't already been redirected.
*/
STATIC int fd0_redirected = 0;
/*
* And also where to put internal use fds that should be out of the
* way of user defined fds (normally)
*/
STATIC int big_sh_fd = 0;
STATIC const struct renamelist *is_renamed(const struct renamelist *, int);
STATIC void fd_rename(struct redirtab *, int, int);
STATIC int * saved_redirected_fd(int);
STATIC void free_rl(struct redirtab *, int);
STATIC void openredirect(union node *, char[10], int);
STATIC int openhere(const union node *);
STATIC int copyfd(int, int, int);
STATIC void find_big_fd(void);
struct shell_fds { /* keep track of internal shell fds */
struct shell_fds *nxt;
void (*cb)(int, int);
int fd;
};
STATIC struct shell_fds *sh_fd_list;
STATIC int pick_new_fd(int);
STATIC void renumber_sh_fd(struct shell_fds *);
STATIC struct shell_fds *sh_fd(int);
STATIC const struct renamelist *
is_renamed(const struct renamelist *rl, int fd)
{
while (rl != NULL) {
if (rl->orig == fd)
return rl;
rl = rl->next;
}
return NULL;
}
STATIC int *
saved_redirected_fd(int fd)
{
struct redirtab *rt;
struct renamelist *rl;
for (rt = redirlist; rt != NULL; rt = rt->next) {
for (rl = rt->renamed; rl != NULL; rl = rl->next) {
if (rl->into == fd)
return &rl->into;
}
}
return NULL;
}
STATIC void
free_rl(struct redirtab *rt, int reset)
{
struct renamelist *rl, *rn = rt->renamed;
while ((rl = rn) != NULL) {
rn = rl->next;
if (rl->orig == 0)
fd0_redirected--;
VTRACE(DBG_REDIR, ("popredir %d%s: %s",
rl->orig, rl->orig==0 ? " (STDIN)" : "",
reset ? "" : "no reset\n"));
if (reset) {
if (rl->into < 0) {
VTRACE(DBG_REDIR, ("closed\n"));
close(rl->orig);
} else {
VTRACE(DBG_REDIR, ("from %d\n", rl->into));
movefd(rl->into, rl->orig);
}
}
ckfree(rl);
}
rt->renamed = NULL;
}
STATIC void
fd_rename(struct redirtab *rt, int from, int to)
{
/* XXX someday keep a short list (8..10) of freed renamelists XXX */
struct renamelist *rl = ckmalloc(sizeof(struct renamelist));
rl->next = rt->renamed;
rt->renamed = rl;
rl->orig = from;
rl->into = to;
}
/*
* Process a list of redirection commands. If the REDIR_PUSH flag is set,
* old file descriptors are stashed away so that the redirection can be
* undone by calling popredir. If the REDIR_BACKQ flag is set, then the
* standard output, and the standard error if it becomes a duplicate of
* stdout, is saved in memory.
*/
void
redirect(union node *redir, int flags)
{
union node *n;
struct redirtab *sv = NULL;
int i;
int fd;
char memory[10]; /* file descriptors to write to memory */
CTRACE(DBG_REDIR, ("redirect(F=0x%x):%s\n", flags, redir?"":" NONE"));
for (i = 10 ; --i >= 0 ; )
memory[i] = 0;
memory[1] = flags & REDIR_BACKQ;
if (flags & REDIR_PUSH) {
/*
* We don't have to worry about REDIR_VFORK here, as
* flags & REDIR_PUSH is never true if REDIR_VFORK is set.
*/
sv = ckmalloc(sizeof (struct redirtab));
sv->renamed = NULL;
sv->next = redirlist;
redirlist = sv;
}
for (n = redir ; n ; n = n->nfile.next) {
int *renamed;
fd = n->nfile.fd;
VTRACE(DBG_REDIR, ("redir %d (max=%d limit=%ld) ",
fd, max_user_fd, user_fd_limit));
if (fd < user_fd_limit && fd > max_user_fd)
max_user_fd = fd;
if ((n->nfile.type == NTOFD || n->nfile.type == NFROMFD) &&
n->ndup.dupfd == fd) {
VTRACE(DBG_REDIR, ("!cloexec\n"));
if (sh_fd(fd) != NULL ||
saved_redirected_fd(fd) != NULL)
error("fd %d: %s", fd, strerror(EBADF));
/* redirect from/to same file descriptor */
/* make sure it stays open */
if (fcntl(fd, F_SETFD, 0) < 0)
error("fd %d: %s", fd, strerror(errno));
continue;
}
if ((renamed = saved_redirected_fd(fd)) != NULL) {
int to = pick_new_fd(fd);
VTRACE(DBG_REDIR,
("redirect: moved holding fd %d to %d\n", fd, to));
*renamed = to;
if (to != fd) /* always... */
(void)close(fd);
}
renumber_sh_fd(sh_fd(fd));
if ((flags & REDIR_PUSH) && !is_renamed(sv->renamed, fd)) {
int bigfd;
INTOFF;
if (big_sh_fd < 10)
find_big_fd();
if ((bigfd = big_sh_fd) < max_user_fd)
bigfd = max_user_fd;
if ((i = fcntl(fd, F_DUPFD, bigfd + 1)) == -1) {
switch (errno) {
case EBADF:
i = CLOSED;
break;
case EMFILE:
case EINVAL:
find_big_fd();
i = fcntl(fd, F_DUPFD, big_sh_fd);
if (i >= 0)
break;
if (errno == EMFILE || errno == EINVAL)
i = fcntl(fd, F_DUPFD, 3);
if (i >= 0)
break;
/* FALLTHRU */
default:
error("%d: %s", fd, strerror(errno));
/* NOTREACHED */
}
}
if (i >= 0)
(void)fcntl(i, F_SETFD, FD_CLOEXEC);
fd_rename(sv, fd, i);
VTRACE(DBG_REDIR, ("fd %d saved as %d ", fd, i));
INTON;
}
VTRACE(DBG_REDIR, ("%s\n", fd == 0 ? "STDIN" : ""));
if (fd == 0)
fd0_redirected++;
openredirect(n, memory, flags);
}
if (memory[1])
out1 = &memout;
if (memory[2])
out2 = &memout;
}
STATIC void
openredirect(union node *redir, char memory[10], int flags)
{
struct stat sb;
int fd = redir->nfile.fd;
char *fname;
int f;
int eflags, cloexec;
/*
* We suppress interrupts so that we won't leave open file
* descriptors around. This may not be such a good idea because
* an open of a device or a fifo can block indefinitely.
*/
INTOFF;
if (fd < 10)
memory[fd] = 0;
switch (redir->nfile.type) {
case NFROM:
fname = redir->nfile.expfname;
if (flags & REDIR_VFORK)
eflags = O_NONBLOCK;
else
eflags = 0;
if ((f = open(fname, O_RDONLY|eflags)) < 0)
goto eopen;
VTRACE(DBG_REDIR, ("openredirect(< '%s') -> %d [%#x]",
fname, f, eflags));
if (eflags)
(void)fcntl(f, F_SETFL, fcntl(f, F_GETFL, 0) & ~eflags);
break;
case NFROMTO:
fname = redir->nfile.expfname;
if ((f = open(fname, O_RDWR|O_CREAT, 0666)) < 0)
goto ecreate;
VTRACE(DBG_REDIR, ("openredirect(<> '%s') -> %d", fname, f));
break;
case NTO:
if (Cflag) {
fname = redir->nfile.expfname;
if ((f = open(fname, O_WRONLY)) == -1) {
if ((f = open(fname, O_WRONLY|O_CREAT|O_EXCL,
0666)) < 0)
goto ecreate;
} else if (fstat(f, &sb) == -1) {
int serrno = errno;
close(f);
errno = serrno;
goto ecreate;
} else if (S_ISREG(sb.st_mode)) {
close(f);
errno = EEXIST;
goto ecreate;
}
VTRACE(DBG_REDIR, ("openredirect(>| '%s') -> %d",
fname, f));
break;
}
/* FALLTHROUGH */
case NCLOBBER:
fname = redir->nfile.expfname;
if ((f = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) < 0)
goto ecreate;
VTRACE(DBG_REDIR, ("openredirect(> '%s') -> %d", fname, f));
break;
case NAPPEND:
fname = redir->nfile.expfname;
if ((f = open(fname, O_WRONLY|O_CREAT|O_APPEND, 0666)) < 0)
goto ecreate;
VTRACE(DBG_REDIR, ("openredirect(>> '%s') -> %d", fname, f));
break;
case NTOFD:
case NFROMFD:
if (redir->ndup.dupfd >= 0) { /* if not ">&-" */
if (sh_fd(redir->ndup.dupfd) != NULL ||
saved_redirected_fd(redir->ndup.dupfd) != NULL)
error("Redirect (from %d to %d) failed: %s",
redir->ndup.dupfd, fd, strerror(EBADF));
if (fd < 10 && redir->ndup.dupfd < 10 &&
memory[redir->ndup.dupfd])
memory[fd] = 1;
else if (copyfd(redir->ndup.dupfd, fd,
(flags & REDIR_KEEP) == 0) < 0)
error("Redirect (from %d to %d) failed: %s",
redir->ndup.dupfd, fd, strerror(errno));
VTRACE(DBG_REDIR, ("openredirect: %d%c&%d\n", fd,
"<>"[redir->nfile.type==NTOFD], redir->ndup.dupfd));
} else {
(void) close(fd);
VTRACE(DBG_REDIR, ("openredirect: %d%c&-\n", fd,
"<>"[redir->nfile.type==NTOFD]));
}
INTON;
return;
case NHERE:
case NXHERE:
VTRACE(DBG_REDIR, ("openredirect: %d<<...", fd));
f = openhere(redir);
break;
default:
abort();
}
cloexec = fd > 2 && (flags & REDIR_KEEP) == 0 && !posix;
if (f != fd) {
VTRACE(DBG_REDIR, (" -> %d", fd));
if (copyfd(f, fd, cloexec) < 0) {
int e = errno;
VTRACE(DBG_REDIR, (" failed: %s\n", strerror(e)));
close(f);
error("redirect reassignment (fd %d) failed: %s", fd,
strerror(e));
}
close(f);
} else if (cloexec)
(void)fcntl(f, F_SETFD, FD_CLOEXEC);
VTRACE(DBG_REDIR, ("%s\n", cloexec ? " cloexec" : ""));
INTON;
return;
ecreate:
exerrno = 1;
error("cannot create %s: %s", fname, errmsg(errno, E_CREAT));
eopen:
exerrno = 1;
error("cannot open %s: %s", fname, errmsg(errno, E_OPEN));
}
/*
* Handle here documents. Normally we fork off a process to write the
* data to a pipe. If the document is short, we can stuff the data in
* the pipe without forking.
*/
STATIC int
openhere(const union node *redir)
{
int pip[2];
int len = 0;
if (pipe(pip) < 0)
error("Pipe call failed");
len = strlen(redir->nhere.text);
VTRACE(DBG_REDIR, ("openhere(%p) [%d] \"%.*s\"%s\n", redir, len,
(len < 40 ? len : 40), redir->nhere.text, (len < 40 ? "" : "...")));
if (len <= PIPESIZE) { /* XXX eventually copy FreeBSD method */
xwrite(pip[1], redir->nhere.text, len);
goto out;
}
VTRACE(DBG_REDIR, (" forking [%d,%d]\n", pip[0], pip[1]));
if (forkshell(NULL, NULL, FORK_NOJOB) == 0) {
close(pip[0]);
signal(SIGINT, SIG_IGN);
signal(SIGQUIT, SIG_IGN);
signal(SIGHUP, SIG_IGN);
#ifdef SIGTSTP
signal(SIGTSTP, SIG_IGN);
#endif
signal(SIGPIPE, SIG_DFL);
xwrite(pip[1], redir->nhere.text, len);
VTRACE(DBG_PROCS|DBG_REDIR, ("wrote here doc. exiting(0)\n"));
_exit(0);
}
VTRACE(DBG_REDIR, ("openhere (closing %d)", pip[1]));
out:
close(pip[1]);
VTRACE(DBG_REDIR, (" (pipe fd=%d)", pip[0]));
return pip[0];
}
/*
* Undo the effects of the last redirection.
*/
void
popredir(void)
{
struct redirtab *rp = redirlist;
INTOFF;
free_rl(rp, 1);
redirlist = rp->next;
ckfree(rp);
INTON;
}
/*
* Undo all redirections. Called on error or interrupt.
*/
#ifdef mkinit
INCLUDE "redir.h"
RESET {
while (redirlist)
popredir();
}
SHELLPROC {
clearredir(0);
}
#endif
/* Return true if fd 0 has already been redirected at least once. */
int
fd0_redirected_p(void)
{
return fd0_redirected != 0;
}
/*
* Discard all saved file descriptors.
*/
void
clearredir(int vforked)
{
struct redirtab *rp;
struct renamelist *rl;
for (rp = redirlist ; rp ; rp = rp->next) {
if (!vforked)
free_rl(rp, 0);
else for (rl = rp->renamed; rl; rl = rl->next)
if (rl->into >= 0)
close(rl->into);
}
}
/*
* Copy a file descriptor to be == to.
* cloexec indicates if we want close-on-exec or not.
* Returns -1 if any error occurs.
*/
STATIC int
copyfd(int from, int to, int cloexec)
{
int newfd;
if (cloexec && to > 2) {
#ifdef O_CLOEXEC
newfd = dup3(from, to, O_CLOEXEC);
#else
newfd = dup2(from, to);
fcntl(newfd, F_SETFD, fcntl(newfd,F_GETFD) | FD_CLOEXEC);
#endif
} else
newfd = dup2(from, to);
return newfd;
}
/*
* rename fd from to be fd to (closing from).
* close-on-exec is never set on 'to' (unless
* from==to and it was set on from) - ie: a no-op
* returns to (or errors() if an error occurs).
*
* This is mostly used for rearranging the
* results from pipe().
*/
int
movefd(int from, int to)
{
if (from == to)
return to;
(void) close(to);
if (copyfd(from, to, 0) != to) {
int e = errno;
(void) close(from);
error("Unable to make fd %d: %s", to, strerror(e));
}
(void) close(from);
return to;
}
STATIC void
find_big_fd(void)
{
int i, fd;
static int last_start = 3; /* aim to keep sh fd's under 20 */
if (last_start < 10)
last_start++;
for (i = (1 << last_start); i >= 10; i >>= 1) {
if ((fd = fcntl(0, F_DUPFD, i - 1)) >= 0) {
close(fd);
break;
}
}
fd = (i / 5) * 4;
if (fd < 10)
fd = 10;
big_sh_fd = fd;
}
/*
* If possible, move file descriptor fd out of the way
* of expected user fd values. Returns the new fd
* (which may be the input fd if things do not go well.)
* Always set close-on-exec on the result, and close
* the input fd unless it is to be our result.
*/
int
to_upper_fd(int fd)
{
int i;
VTRACE(DBG_REDIR|DBG_OUTPUT, ("to_upper_fd(%d)", fd));
if (big_sh_fd < 10 || big_sh_fd >= user_fd_limit)
find_big_fd();
do {
i = fcntl(fd, F_DUPFD_CLOEXEC, big_sh_fd);
if (i >= 0) {
if (fd != i)
close(fd);
VTRACE(DBG_REDIR|DBG_OUTPUT, ("-> %d\n", i));
return i;
}
if (errno != EMFILE && errno != EINVAL)
break;
find_big_fd();
} while (big_sh_fd > 10);
/*
* If we wanted to move this fd to some random high number
* we certainly do not intend to pass it through exec, even
* if the reassignment failed.
*/
(void)fcntl(fd, F_SETFD, FD_CLOEXEC);
VTRACE(DBG_REDIR|DBG_OUTPUT, (" fails ->%d\n", fd));
return fd;
}
void
register_sh_fd(int fd, void (*cb)(int, int))
{
struct shell_fds *fp;
fp = ckmalloc(sizeof (struct shell_fds));
if (fp != NULL) {
fp->nxt = sh_fd_list;
sh_fd_list = fp;
fp->fd = fd;
fp->cb = cb;
}
}
void
sh_close(int fd)
{
struct shell_fds **fpp, *fp;
fpp = &sh_fd_list;
while ((fp = *fpp) != NULL) {
if (fp->fd == fd) {
*fpp = fp->nxt;
ckfree(fp);
break;
}
fpp = &fp->nxt;
}
(void)close(fd);
}
STATIC struct shell_fds *
sh_fd(int fd)
{
struct shell_fds *fp;
for (fp = sh_fd_list; fp != NULL; fp = fp->nxt)
if (fp->fd == fd)
return fp;
return NULL;
}
STATIC int
pick_new_fd(int fd)
{
int to;
to = fcntl(fd, F_DUPFD_CLOEXEC, big_sh_fd);
if (to == -1 && big_sh_fd >= 22)
to = fcntl(fd, F_DUPFD_CLOEXEC, big_sh_fd/2);
if (to == -1)
to = fcntl(fd, F_DUPFD_CLOEXEC, fd + 1);
if (to == -1)
to = fcntl(fd, F_DUPFD_CLOEXEC, 10);
if (to == -1)
to = fcntl(fd, F_DUPFD_CLOEXEC, 3);
if (to == -1)
error("insufficient file descriptors available");
CLOEXEC(to);
return to;
}
STATIC void
renumber_sh_fd(struct shell_fds *fp)
{
int to;
if (fp == NULL)
return;
/*
* if we have had a collision, and the sh fd was a "big" one
* try moving the sh fd base to a higher number (if possible)
* so future sh fds are less likely to be in the user's sights
* (incl this one when moved)
*/
if (fp->fd >= big_sh_fd)
find_big_fd();
to = pick_new_fd(fp->fd);
if (fp->fd == to) /* impossible? */
return;
VTRACE(DBG_REDIR, ("renumber_sh_fd: moved shell fd %d to %d\n",
fp->fd, to));
(*fp->cb)(fp->fd, to);
(void)close(fp->fd);
fp->fd = to;
}
static const struct flgnames {
const char *name;
uint16_t minch;
uint32_t value;
} nv[] = {
#ifdef O_APPEND
{ "append", 2, O_APPEND },
#else
# define O_APPEND 0
#endif
#ifdef O_ASYNC
{ "async", 2, O_ASYNC },
#else
# define O_ASYNC 0
#endif
#ifdef O_SYNC
{ "sync", 2, O_SYNC },
#else
# define O_SYNC 0
#endif
#ifdef O_NONBLOCK
{ "nonblock", 3, O_NONBLOCK },
#else
# define O_NONBLOCK 0
#endif
#ifdef O_FSYNC
{ "fsync", 2, O_FSYNC },
#else
# define O_FSYNC 0
#endif
#ifdef O_DSYNC
{ "dsync", 2, O_DSYNC },
#else
# define O_DSYNC 0
#endif
#ifdef O_RSYNC
{ "rsync", 2, O_RSYNC },
#else
# define O_RSYNC 0
#endif
#ifdef O_ALT_IO
{ "altio", 2, O_ALT_IO },
#else
# define O_ALT_IO 0
#endif
#ifdef O_DIRECT
{ "direct", 2, O_DIRECT },
#else
# define O_DIRECT 0
#endif
#ifdef O_NOSIGPIPE
{ "nosigpipe", 3, O_NOSIGPIPE },
#else
# define O_NOSIGPIPE 0
#endif
#define ALLFLAGS (O_APPEND|O_ASYNC|O_SYNC|O_NONBLOCK|O_DSYNC|O_RSYNC|\
O_ALT_IO|O_DIRECT|O_NOSIGPIPE)
#ifndef O_CLOEXEC
# define O_CLOEXEC ((~ALLFLAGS) ^ ((~ALLFLAGS) & ((~ALLFLAGS) - 1)))
#endif
/* for any system we support, close on exec is always defined */
{ "cloexec", 2, O_CLOEXEC },
{ 0, 0, 0 }
};
#ifndef O_ACCMODE
# define O_ACCMODE 0
#endif
#ifndef O_RDONLY
# define O_RDONLY 0
#endif
#ifndef O_WRONLY
# define O_WRONLY 0
#endif
#ifndef O_RWDR
# define O_RWDR 0
#endif
#ifndef O_SHLOCK
# define O_SHLOCK 0
#endif
#ifndef O_EXLOCK
# define O_EXLOCK 0
#endif
#ifndef O_NOFOLLOW
# define O_NOFOLLOW 0
#endif
#ifndef O_CREAT
# define O_CREAT 0
#endif
#ifndef O_TRUNC
# define O_TRUNC 0
#endif
#ifndef O_EXCL
# define O_EXCL 0
#endif
#ifndef O_NOCTTY
# define O_NOCTTY 0
#endif
#ifndef O_DIRECTORY
# define O_DIRECTORY 0
#endif
#ifndef O_REGULAR
# define O_REGULAR 0
#endif
/*
* flags that F_GETFL might return that we want to ignore
*
* F_GETFL should not actually return these, they're all just open()
* modifiers, rather than state, but just in case...
*/
#define IGNFLAGS (O_ACCMODE|O_RDONLY|O_WRONLY|O_RDWR|O_SHLOCK|O_EXLOCK| \
O_NOFOLLOW|O_CREAT|O_TRUNC|O_EXCL|O_NOCTTY|O_DIRECTORY|O_REGULAR)
static int
getflags(int fd, int p)
{
int c, f;
if (sh_fd(fd) != NULL || saved_redirected_fd(fd) != NULL) {
if (!p)
return -1;
error("Can't get status for fd=%d (%s)", fd, strerror(EBADF));
}
if ((c = fcntl(fd, F_GETFD)) == -1) {
if (!p)
return -1;
error("Can't get status for fd=%d (%s)", fd, strerror(errno));
}
if ((f = fcntl(fd, F_GETFL)) == -1) {
if (!p)
return -1;
error("Can't get flags for fd=%d (%s)", fd, strerror(errno));
}
f &= ~IGNFLAGS; /* clear anything we know about, but ignore */
if (c & FD_CLOEXEC)
f |= O_CLOEXEC;
return f;
}
static void
printone(int fd, int p, int verbose, int pfd)
{
int f = getflags(fd, p);
const struct flgnames *fn;
if (f == -1)
return;
if (pfd)
outfmt(out1, "%d: ", fd);
for (fn = nv; fn->name; fn++) {
if (f & fn->value) {
outfmt(out1, "%s%s", verbose ? "+" : "", fn->name);
f &= ~fn->value;
} else if (verbose)
outfmt(out1, "-%s", fn->name);
else
continue;
if (f || (verbose && fn[1].name))
outfmt(out1, ",");
}
if (verbose && f) /* f should be normally be 0 */
outfmt(out1, " +%#x", f);
outfmt(out1, "\n");
}
static void
parseflags(char *s, int *p, int *n)
{
int *v, *w;
const struct flgnames *fn;
size_t len;
*p = 0;
*n = 0;
for (s = strtok(s, ","); s; s = strtok(NULL, ",")) {
switch (*s++) {
case '+':
v = p;
w = n;
break;
case '-':
v = n;
w = p;
break;
default:
error("Missing +/- indicator before flag %s", s-1);
}
len = strlen(s);
for (fn = nv; fn->name; fn++)
if (len >= fn->minch && strncmp(s,fn->name,len) == 0) {
*v |= fn->value;
*w &=~ fn->value;
break;
}
if (fn->name == 0)
error("Bad flag `%s'", s);
}
}
static void
setone(int fd, int pos, int neg, int verbose)
{
int f = getflags(fd, 1);
int n, cloexec;
if (f == -1)
return;
cloexec = -1;
if ((pos & O_CLOEXEC) && !(f & O_CLOEXEC))
cloexec = FD_CLOEXEC;
if ((neg & O_CLOEXEC) && (f & O_CLOEXEC))
cloexec = 0;
if (cloexec != -1 && fcntl(fd, F_SETFD, cloexec) == -1)
error("Can't set status for fd=%d (%s)", fd, strerror(errno));
pos &= ~O_CLOEXEC;
neg &= ~O_CLOEXEC;
f &= ~O_CLOEXEC;
n = f;
n |= pos;
n &= ~neg;
if (n != f && fcntl(fd, F_SETFL, n) == -1)
error("Can't set flags for fd=%d (%s)", fd, strerror(errno));
if (verbose)
printone(fd, 1, verbose, 1);
}
int
fdflagscmd(int argc, char *argv[])
{
char *num;
int verbose = 0, ch, pos = 0, neg = 0;
char *setflags = NULL;
optreset = 1; optind = 1; /* initialize getopt */
while ((ch = getopt(argc, argv, ":vs:")) != -1)
switch ((char)ch) {
case 'v':
verbose = 1;
break;
case 's':
if (setflags)
goto msg;
setflags = optarg;
break;
case '?':
default:
msg:
error("Usage: fdflags [-v] [-s <flags> fd] [fd...]");
/* NOTREACHED */
}
argc -= optind, argv += optind;
if (setflags)
parseflags(setflags, &pos, &neg);
if (argc == 0) {
int i;
if (setflags)
goto msg;
for (i = 0; i <= max_user_fd; i++)
printone(i, 0, verbose, 1);
} else while ((num = *argv++) != NULL) {
int fd = number(num);
while (num[0] == '0' && num[1] != '\0') /* skip 0's */
num++;
if (strlen(num) > 5 ||
(fd >= user_fd_limit && fd > max_user_fd))
error("%s: too big to be a file descriptor", num);
if (setflags)
setone(fd, pos, neg, verbose);
else
printone(fd, 1, verbose, argc > 1);
}
flushout(out1);
if (io_err(out1)) {
out2str("fdflags: I/O error\n");
return 1;
}
return 0;
}
#undef MAX /* in case we inherited them from somewhere */
#undef MIN
#define MIN(a,b) (/*CONSTCOND*/((a)<=(b)) ? (a) : (b))
#define MAX(a,b) (/*CONSTCOND*/((a)>=(b)) ? (a) : (b))
/* now make the compiler work for us... */
#define MIN_REDIR MIN(MIN(MIN(MIN(NTO,NFROM), MIN(NTOFD,NFROMFD)), \
MIN(MIN(NCLOBBER,NAPPEND), MIN(NHERE,NXHERE))), NFROMTO)
#define MAX_REDIR MAX(MAX(MAX(MAX(NTO,NFROM), MAX(NTOFD,NFROMFD)), \
MAX(MAX(NCLOBBER,NAPPEND), MAX(NHERE,NXHERE))), NFROMTO)
static const char *redir_sym[MAX_REDIR - MIN_REDIR + 1] = {
[NTO - MIN_REDIR]= ">",
[NFROM - MIN_REDIR]= "<",
[NTOFD - MIN_REDIR]= ">&",
[NFROMFD - MIN_REDIR]= "<&",
[NCLOBBER - MIN_REDIR]= ">|",
[NAPPEND - MIN_REDIR]= ">>",
[NHERE - MIN_REDIR]= "<<",
[NXHERE - MIN_REDIR]= "<<",
[NFROMTO - MIN_REDIR]= "<>",
};
int
outredir(struct output *out, union node *n, int sep)
{
if (n == NULL)
return 0;
if (n->type < MIN_REDIR || n->type > MAX_REDIR ||
redir_sym[n->type - MIN_REDIR] == NULL)
return 0;
if (sep)
outc(sep, out);
/*
* ugly, but all redir node types have "fd" in same slot...
* (and code other places assumes it as well)
*/
if ((redir_sym[n->type - MIN_REDIR][0] == '<' && n->nfile.fd != 0) ||
(redir_sym[n->type - MIN_REDIR][0] == '>' && n->nfile.fd != 1))
outfmt(out, "%d", n->nfile.fd);
outstr(redir_sym[n->type - MIN_REDIR], out);
switch (n->type) {
case NHERE:
outstr("'...'", out);
break;
case NXHERE:
outstr("...", out);
break;
case NTOFD:
case NFROMFD:
if (n->ndup.dupfd < 0)
outc('-', out);
else
outfmt(out, "%d", n->ndup.dupfd);
break;
default:
outstr(n->nfile.expfname, out);
break;
}
return 1;
}