| 1 | /* $NetBSD: redir.c,v 1.29 2004/07/08 03:57:33 christos Exp $ */
|
|---|
| 2 |
|
|---|
| 3 | /*-
|
|---|
| 4 | * Copyright (c) 1991, 1993
|
|---|
| 5 | * The Regents of the University of California. All rights reserved.
|
|---|
| 6 | *
|
|---|
| 7 | * This code is derived from software contributed to Berkeley by
|
|---|
| 8 | * Kenneth Almquist.
|
|---|
| 9 | *
|
|---|
| 10 | * Redistribution and use in source and binary forms, with or without
|
|---|
| 11 | * modification, are permitted provided that the following conditions
|
|---|
| 12 | * are met:
|
|---|
| 13 | * 1. Redistributions of source code must retain the above copyright
|
|---|
| 14 | * notice, this list of conditions and the following disclaimer.
|
|---|
| 15 | * 2. Redistributions in binary form must reproduce the above copyright
|
|---|
| 16 | * notice, this list of conditions and the following disclaimer in the
|
|---|
| 17 | * documentation and/or other materials provided with the distribution.
|
|---|
| 18 | * 3. Neither the name of the University nor the names of its contributors
|
|---|
| 19 | * may be used to endorse or promote products derived from this software
|
|---|
| 20 | * without specific prior written permission.
|
|---|
| 21 | *
|
|---|
| 22 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
|
|---|
| 23 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|---|
| 24 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|---|
| 25 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
|
|---|
| 26 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|---|
| 27 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|---|
| 28 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|---|
| 29 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|---|
| 30 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|---|
| 31 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|---|
| 32 | * SUCH DAMAGE.
|
|---|
| 33 | */
|
|---|
| 34 |
|
|---|
| 35 | #if 0
|
|---|
| 36 | #ifndef lint
|
|---|
| 37 | static char sccsid[] = "@(#)redir.c 8.2 (Berkeley) 5/4/95";
|
|---|
| 38 | #else
|
|---|
| 39 | __RCSID("$NetBSD: redir.c,v 1.29 2004/07/08 03:57:33 christos Exp $");
|
|---|
| 40 | #endif /* not lint */
|
|---|
| 41 | #endif
|
|---|
| 42 |
|
|---|
| 43 | #include <sys/types.h>
|
|---|
| 44 | #include <limits.h> /* PIPE_BUF */
|
|---|
| 45 | #include <string.h>
|
|---|
| 46 | #include <errno.h>
|
|---|
| 47 | #include <stdlib.h>
|
|---|
| 48 |
|
|---|
| 49 | /*
|
|---|
| 50 | * Code for dealing with input/output redirection.
|
|---|
| 51 | */
|
|---|
| 52 |
|
|---|
| 53 | #include "main.h"
|
|---|
| 54 | #include "shell.h"
|
|---|
| 55 | #include "nodes.h"
|
|---|
| 56 | #include "jobs.h"
|
|---|
| 57 | #include "options.h"
|
|---|
| 58 | #include "expand.h"
|
|---|
| 59 | #include "redir.h"
|
|---|
| 60 | #include "output.h"
|
|---|
| 61 | #include "memalloc.h"
|
|---|
| 62 | #include "error.h"
|
|---|
| 63 | #include "shinstance.h"
|
|---|
| 64 |
|
|---|
| 65 |
|
|---|
| 66 | #define EMPTY -2 /* marks an unused slot in redirtab */
|
|---|
| 67 | #ifndef PIPE_BUF
|
|---|
| 68 | # define PIPESIZE 4096 /* amount of buffering in a pipe */
|
|---|
| 69 | #else
|
|---|
| 70 | # define PIPESIZE PIPE_BUF
|
|---|
| 71 | #endif
|
|---|
| 72 |
|
|---|
| 73 |
|
|---|
| 74 | MKINIT
|
|---|
| 75 | struct redirtab {
|
|---|
| 76 | struct redirtab *next;
|
|---|
| 77 | short renamed[10];
|
|---|
| 78 | };
|
|---|
| 79 |
|
|---|
| 80 |
|
|---|
| 81 | //MKINIT struct redirtab *redirlist;
|
|---|
| 82 |
|
|---|
| 83 | /*
|
|---|
| 84 | * We keep track of whether or not fd0 has been redirected. This is for
|
|---|
| 85 | * background commands, where we want to redirect fd0 to /dev/null only
|
|---|
| 86 | * if it hasn't already been redirected.
|
|---|
| 87 | */
|
|---|
| 88 | //int fd0_redirected = 0;
|
|---|
| 89 |
|
|---|
| 90 | STATIC void openredirect(shinstance *, union node *, char[10], int);
|
|---|
| 91 | STATIC int openhere(shinstance *, union node *);
|
|---|
| 92 |
|
|---|
| 93 |
|
|---|
| 94 | /*
|
|---|
| 95 | * Process a list of redirection commands. If the REDIR_PUSH flag is set,
|
|---|
| 96 | * old file descriptors are stashed away so that the redirection can be
|
|---|
| 97 | * undone by calling popredir. If the REDIR_BACKQ flag is set, then the
|
|---|
| 98 | * standard output, and the standard error if it becomes a duplicate of
|
|---|
| 99 | * stdout, is saved in memory.
|
|---|
| 100 | */
|
|---|
| 101 |
|
|---|
| 102 | void
|
|---|
| 103 | redirect(shinstance *psh, union node *redir, int flags)
|
|---|
| 104 | {
|
|---|
| 105 | union node *n;
|
|---|
| 106 | struct redirtab *sv = NULL;
|
|---|
| 107 | int i;
|
|---|
| 108 | int fd;
|
|---|
| 109 | int try;
|
|---|
| 110 | char memory[10]; /* file descriptors to write to memory */
|
|---|
| 111 |
|
|---|
| 112 | for (i = 10 ; --i >= 0 ; )
|
|---|
| 113 | memory[i] = 0;
|
|---|
| 114 | memory[1] = flags & REDIR_BACKQ;
|
|---|
| 115 | if (flags & REDIR_PUSH) {
|
|---|
| 116 | /* We don't have to worry about REDIR_VFORK here, as
|
|---|
| 117 | * flags & REDIR_PUSH is never true if REDIR_VFORK is set.
|
|---|
| 118 | */
|
|---|
| 119 | sv = ckmalloc(sizeof (struct redirtab));
|
|---|
| 120 | for (i = 0 ; i < 10 ; i++)
|
|---|
| 121 | sv->renamed[i] = EMPTY;
|
|---|
| 122 | sv->next = psh->redirlist;
|
|---|
| 123 | psh->redirlist = sv;
|
|---|
| 124 | }
|
|---|
| 125 | for (n = redir ; n ; n = n->nfile.next) {
|
|---|
| 126 | fd = n->nfile.fd;
|
|---|
| 127 | try = 0;
|
|---|
| 128 | if ((n->nfile.type == NTOFD || n->nfile.type == NFROMFD) &&
|
|---|
| 129 | n->ndup.dupfd == fd)
|
|---|
| 130 | continue; /* redirect from/to same file descriptor */
|
|---|
| 131 |
|
|---|
| 132 | if ((flags & REDIR_PUSH) && sv->renamed[fd] == EMPTY) {
|
|---|
| 133 | INTOFF;
|
|---|
| 134 | again:
|
|---|
| 135 | if ((i = shfile_fcntl(&psh->fdtab, fd, F_DUPFD, 10)) == -1) {
|
|---|
| 136 | switch (errno) {
|
|---|
| 137 | case EBADF:
|
|---|
| 138 | if (!try) {
|
|---|
| 139 | openredirect(psh, n, memory, flags);
|
|---|
| 140 | try++;
|
|---|
| 141 | goto again;
|
|---|
| 142 | }
|
|---|
| 143 | /* FALLTHROUGH*/
|
|---|
| 144 | default:
|
|---|
| 145 | INTON;
|
|---|
| 146 | error(psh, "%d: %s", fd, strerror(errno));
|
|---|
| 147 | /* NOTREACHED */
|
|---|
| 148 | }
|
|---|
| 149 | }
|
|---|
| 150 | if (!try) {
|
|---|
| 151 | sv->renamed[fd] = i;
|
|---|
| 152 | shfile_close(&psh->fdtab, fd);
|
|---|
| 153 | }
|
|---|
| 154 | INTON;
|
|---|
| 155 | } else {
|
|---|
| 156 | shfile_close(&psh->fdtab, fd);
|
|---|
| 157 | }
|
|---|
| 158 | if (fd == 0)
|
|---|
| 159 | psh->fd0_redirected++;
|
|---|
| 160 | if (!try)
|
|---|
| 161 | openredirect(psh, n, memory, flags);
|
|---|
| 162 | }
|
|---|
| 163 | if (memory[1])
|
|---|
| 164 | psh->out1 = &psh->memout;
|
|---|
| 165 | if (memory[2])
|
|---|
| 166 | psh->out2 = &psh->memout;
|
|---|
| 167 | }
|
|---|
| 168 |
|
|---|
| 169 |
|
|---|
| 170 | STATIC void
|
|---|
| 171 | openredirect(shinstance *psh, union node *redir, char memory[10], int flags)
|
|---|
| 172 | {
|
|---|
| 173 | int fd = redir->nfile.fd;
|
|---|
| 174 | char *fname;
|
|---|
| 175 | int f;
|
|---|
| 176 | int oflags = O_WRONLY|O_CREAT|O_TRUNC, eflags;
|
|---|
| 177 |
|
|---|
| 178 | /*
|
|---|
| 179 | * We suppress interrupts so that we won't leave open file
|
|---|
| 180 | * descriptors around. This may not be such a good idea because
|
|---|
| 181 | * an open of a device or a fifo can block indefinitely.
|
|---|
| 182 | */
|
|---|
| 183 | INTOFF;
|
|---|
| 184 | memory[fd] = 0;
|
|---|
| 185 | switch (redir->nfile.type) {
|
|---|
| 186 | case NFROM:
|
|---|
| 187 | fname = redir->nfile.expfname;
|
|---|
| 188 | if (flags & REDIR_VFORK)
|
|---|
| 189 | eflags = O_NONBLOCK;
|
|---|
| 190 | else
|
|---|
| 191 | eflags = 0;
|
|---|
| 192 | if ((f = shfile_open(&psh->fdtab, fname, O_RDONLY|eflags, 0)) < 0)
|
|---|
| 193 | goto eopen;
|
|---|
| 194 | if (eflags)
|
|---|
| 195 | (void)shfile_fcntl(&psh->fdtab, f, F_SETFL, shfile_fcntl(&psh->fdtab, f, F_GETFL, 0) & ~eflags);
|
|---|
| 196 | break;
|
|---|
| 197 | case NFROMTO:
|
|---|
| 198 | fname = redir->nfile.expfname;
|
|---|
| 199 | if ((f = shfile_open(&psh->fdtab, fname, O_RDWR|O_CREAT|O_TRUNC, 0666)) < 0)
|
|---|
| 200 | goto ecreate;
|
|---|
| 201 | break;
|
|---|
| 202 | case NTO:
|
|---|
| 203 | if (Cflag(psh))
|
|---|
| 204 | oflags |= O_EXCL;
|
|---|
| 205 | /* FALLTHROUGH */
|
|---|
| 206 | case NCLOBBER:
|
|---|
| 207 | fname = redir->nfile.expfname;
|
|---|
| 208 | if ((f = shfile_open(&psh->fdtab, fname, oflags, 0666)) < 0)
|
|---|
| 209 | goto ecreate;
|
|---|
| 210 | break;
|
|---|
| 211 | case NAPPEND:
|
|---|
| 212 | fname = redir->nfile.expfname;
|
|---|
| 213 | if ((f = shfile_open(&psh->fdtab, fname, O_WRONLY|O_CREAT|O_APPEND, 0666)) < 0)
|
|---|
| 214 | goto ecreate;
|
|---|
| 215 | break;
|
|---|
| 216 | case NTOFD:
|
|---|
| 217 | case NFROMFD:
|
|---|
| 218 | if (redir->ndup.dupfd >= 0) { /* if not ">&-" */
|
|---|
| 219 | if (memory[redir->ndup.dupfd])
|
|---|
| 220 | memory[fd] = 1;
|
|---|
| 221 | else
|
|---|
| 222 | copyfd(psh, redir->ndup.dupfd, fd);
|
|---|
| 223 | }
|
|---|
| 224 | INTON;
|
|---|
| 225 | return;
|
|---|
| 226 | case NHERE:
|
|---|
| 227 | case NXHERE:
|
|---|
| 228 | f = openhere(psh, redir);
|
|---|
| 229 | break;
|
|---|
| 230 | default:
|
|---|
| 231 | sh_abort(psh);
|
|---|
| 232 | }
|
|---|
| 233 |
|
|---|
| 234 | if (f != fd) {
|
|---|
| 235 | copyfd(psh, f, fd);
|
|---|
| 236 | shfile_close(&psh->fdtab, f);
|
|---|
| 237 | }
|
|---|
| 238 | INTON;
|
|---|
| 239 | return;
|
|---|
| 240 | ecreate:
|
|---|
| 241 | error(psh, "cannot create %s: %s", fname, errmsg(psh, errno, E_CREAT));
|
|---|
| 242 | eopen:
|
|---|
| 243 | error(psh, "cannot open %s: %s", fname, errmsg(psh, errno, E_OPEN));
|
|---|
| 244 | }
|
|---|
| 245 |
|
|---|
| 246 |
|
|---|
| 247 | /*
|
|---|
| 248 | * Handle here documents. Normally we fork off a process to write the
|
|---|
| 249 | * data to a pipe. If the document is short, we can stuff the data in
|
|---|
| 250 | * the pipe without forking.
|
|---|
| 251 | */
|
|---|
| 252 |
|
|---|
| 253 | STATIC int
|
|---|
| 254 | openhere(shinstance *psh, union node *redir)
|
|---|
| 255 | {
|
|---|
| 256 | int pip[2];
|
|---|
| 257 | size_t len = 0;
|
|---|
| 258 |
|
|---|
| 259 | if (shfile_pipe(&psh->fdtab, pip) < 0)
|
|---|
| 260 | error(psh, "Pipe call failed");
|
|---|
| 261 | if (redir->type == NHERE) {
|
|---|
| 262 | len = strlen(redir->nhere.doc->narg.text);
|
|---|
| 263 | if (len <= PIPESIZE) {
|
|---|
| 264 | xwrite(psh, pip[1], redir->nhere.doc->narg.text, len);
|
|---|
| 265 | goto out;
|
|---|
| 266 | }
|
|---|
| 267 | }
|
|---|
| 268 | if (forkshell(psh, (struct job *)NULL, (union node *)NULL, FORK_NOJOB) == 0) {
|
|---|
| 269 | shfile_close(&psh->fdtab, pip[0]);
|
|---|
| 270 | sh_signal(psh, SIGINT, SH_SIG_IGN);
|
|---|
| 271 | sh_signal(psh, SIGQUIT, SH_SIG_IGN);
|
|---|
| 272 | sh_signal(psh, SIGHUP, SH_SIG_IGN);
|
|---|
| 273 | #ifdef SIGTSTP
|
|---|
| 274 | sh_signal(psh, SIGTSTP, SH_SIG_IGN);
|
|---|
| 275 | #endif
|
|---|
| 276 | sh_signal(psh, SIGPIPE, SH_SIG_DFL);
|
|---|
| 277 | if (redir->type == NHERE)
|
|---|
| 278 | xwrite(psh, pip[1], redir->nhere.doc->narg.text, len);
|
|---|
| 279 | else
|
|---|
| 280 | expandhere(psh, redir->nhere.doc, pip[1]);
|
|---|
| 281 | sh__exit(psh, 0);
|
|---|
| 282 | }
|
|---|
| 283 | out:
|
|---|
| 284 | shfile_close(&psh->fdtab, pip[1]);
|
|---|
| 285 | return pip[0];
|
|---|
| 286 | }
|
|---|
| 287 |
|
|---|
| 288 |
|
|---|
| 289 |
|
|---|
| 290 | /*
|
|---|
| 291 | * Undo the effects of the last redirection.
|
|---|
| 292 | */
|
|---|
| 293 |
|
|---|
| 294 | void
|
|---|
| 295 | popredir(shinstance *psh)
|
|---|
| 296 | {
|
|---|
| 297 | struct redirtab *rp = psh->redirlist;
|
|---|
| 298 | int i;
|
|---|
| 299 |
|
|---|
| 300 | for (i = 0 ; i < 10 ; i++) {
|
|---|
| 301 | if (rp->renamed[i] != EMPTY) {
|
|---|
| 302 | if (i == 0)
|
|---|
| 303 | psh->fd0_redirected--;
|
|---|
| 304 | shfile_close(&psh->fdtab, i);
|
|---|
| 305 | if (rp->renamed[i] >= 0) {
|
|---|
| 306 | copyfd(psh, rp->renamed[i], i);
|
|---|
| 307 | shfile_close(&psh->fdtab, rp->renamed[i]);
|
|---|
| 308 | }
|
|---|
| 309 | }
|
|---|
| 310 | }
|
|---|
| 311 | INTOFF;
|
|---|
| 312 | psh->redirlist = rp->next;
|
|---|
| 313 | ckfree(rp);
|
|---|
| 314 | INTON;
|
|---|
| 315 | }
|
|---|
| 316 |
|
|---|
| 317 | /*
|
|---|
| 318 | * Undo all redirections. Called on error or interrupt.
|
|---|
| 319 | */
|
|---|
| 320 |
|
|---|
| 321 | #ifdef mkinit
|
|---|
| 322 |
|
|---|
| 323 | INCLUDE "redir.h"
|
|---|
| 324 |
|
|---|
| 325 | RESET {
|
|---|
| 326 | while (psh->redirlist)
|
|---|
| 327 | popredir(psh);
|
|---|
| 328 | }
|
|---|
| 329 |
|
|---|
| 330 | SHELLPROC {
|
|---|
| 331 | clearredir(psh, 0);
|
|---|
| 332 | }
|
|---|
| 333 |
|
|---|
| 334 | #endif
|
|---|
| 335 |
|
|---|
| 336 | /* Return true if fd 0 has already been redirected at least once. */
|
|---|
| 337 | int
|
|---|
| 338 | fd0_redirected_p(shinstance *psh) {
|
|---|
| 339 | return psh->fd0_redirected != 0;
|
|---|
| 340 | }
|
|---|
| 341 |
|
|---|
| 342 | /*
|
|---|
| 343 | * Discard all saved file descriptors.
|
|---|
| 344 | */
|
|---|
| 345 |
|
|---|
| 346 | void
|
|---|
| 347 | clearredir(shinstance *psh, int vforked)
|
|---|
| 348 | {
|
|---|
| 349 | struct redirtab *rp;
|
|---|
| 350 | int i;
|
|---|
| 351 |
|
|---|
| 352 | for (rp = psh->redirlist ; rp ; rp = rp->next) {
|
|---|
| 353 | for (i = 0 ; i < 10 ; i++) {
|
|---|
| 354 | if (rp->renamed[i] >= 0) {
|
|---|
| 355 | shfile_close(&psh->fdtab, rp->renamed[i]);
|
|---|
| 356 | }
|
|---|
| 357 | if (!vforked)
|
|---|
| 358 | rp->renamed[i] = EMPTY;
|
|---|
| 359 | }
|
|---|
| 360 | }
|
|---|
| 361 | }
|
|---|
| 362 |
|
|---|
| 363 |
|
|---|
| 364 |
|
|---|
| 365 | /*
|
|---|
| 366 | * Copy a file descriptor to be >= to. Returns -1
|
|---|
| 367 | * if the source file descriptor is closed, EMPTY if there are no unused
|
|---|
| 368 | * file descriptors left.
|
|---|
| 369 | */
|
|---|
| 370 |
|
|---|
| 371 | int
|
|---|
| 372 | copyfd(shinstance *psh, int from, int to)
|
|---|
| 373 | {
|
|---|
| 374 | int newfd;
|
|---|
| 375 |
|
|---|
| 376 | newfd = shfile_fcntl(&psh->fdtab, from, F_DUPFD, to);
|
|---|
| 377 | if (newfd < 0) {
|
|---|
| 378 | if (errno == EMFILE)
|
|---|
| 379 | return EMPTY;
|
|---|
| 380 | else
|
|---|
| 381 | error(psh, "%d: %s", from, strerror(errno));
|
|---|
| 382 | }
|
|---|
| 383 | return newfd;
|
|---|
| 384 | }
|
|---|
