1/*-
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Kenneth Almquist.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#ifndef lint
34#if 0
35static char sccsid[] = "@(#)redir.c 8.2 (Berkeley) 5/4/95";
36#endif
37#endif /* not lint */
38#include <sys/cdefs.h>
| 1/*-
2 * Copyright (c) 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Kenneth Almquist.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 * 4. Neither the name of the University nor the names of its contributors
17 * may be used to endorse or promote products derived from this software
18 * without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 */
32
33#ifndef lint
34#if 0
35static char sccsid[] = "@(#)redir.c 8.2 (Berkeley) 5/4/95";
36#endif
37#endif /* not lint */
38#include <sys/cdefs.h>
|
39__FBSDID("$FreeBSD: head/bin/sh/redir.c 213760 2010-10-13 04:01:01Z obrien $");
| 39__FBSDID("$FreeBSD: head/bin/sh/redir.c 213811 2010-10-13 22:18:03Z obrien $");
|
40
41#include <sys/types.h>
42#include <sys/stat.h>
43#include <signal.h>
44#include <string.h>
45#include <fcntl.h>
46#include <errno.h>
47#include <unistd.h>
48#include <stdlib.h>
49
50/*
51 * Code for dealing with input/output redirection.
52 */
53
54#include "shell.h"
55#include "nodes.h"
56#include "jobs.h"
57#include "expand.h"
58#include "redir.h"
59#include "output.h"
60#include "memalloc.h"
61#include "error.h"
62#include "options.h"
63
64
65#define EMPTY -2 /* marks an unused slot in redirtab */
66#define CLOSED -1 /* fd was not open before redir */
67#define PIPESIZE 4096 /* amount of buffering in a pipe */
68
69
70MKINIT
71struct redirtab {
72 struct redirtab *next;
73 int renamed[10];
74};
75
76
77MKINIT struct redirtab *redirlist;
78
79/*
80 * We keep track of whether or not fd0 has been redirected. This is for
81 * background commands, where we want to redirect fd0 to /dev/null only
82 * if it hasn't already been redirected.
83*/
84static int fd0_redirected = 0;
85
| 40
41#include <sys/types.h>
42#include <sys/stat.h>
43#include <signal.h>
44#include <string.h>
45#include <fcntl.h>
46#include <errno.h>
47#include <unistd.h>
48#include <stdlib.h>
49
50/*
51 * Code for dealing with input/output redirection.
52 */
53
54#include "shell.h"
55#include "nodes.h"
56#include "jobs.h"
57#include "expand.h"
58#include "redir.h"
59#include "output.h"
60#include "memalloc.h"
61#include "error.h"
62#include "options.h"
63
64
65#define EMPTY -2 /* marks an unused slot in redirtab */
66#define CLOSED -1 /* fd was not open before redir */
67#define PIPESIZE 4096 /* amount of buffering in a pipe */
68
69
70MKINIT
71struct redirtab {
72 struct redirtab *next;
73 int renamed[10];
74};
75
76
77MKINIT struct redirtab *redirlist;
78
79/*
80 * We keep track of whether or not fd0 has been redirected. This is for
81 * background commands, where we want to redirect fd0 to /dev/null only
82 * if it hasn't already been redirected.
83*/
84static int fd0_redirected = 0;
85
|
86STATIC void openredirect(union node *, char[10 ]);
87STATIC int openhere(union node *);
| 86static void openredirect(union node *, char[10 ]);
87static int openhere(union node *);
|
88
89
90/*
91 * Process a list of redirection commands. If the REDIR_PUSH flag is set,
92 * old file descriptors are stashed away so that the redirection can be
93 * undone by calling popredir. If the REDIR_BACKQ flag is set, then the
94 * standard output, and the standard error if it becomes a duplicate of
95 * stdout, is saved in memory.
96 */
97
98void
99redirect(union node *redir, int flags)
100{
101 union node *n;
102 struct redirtab *sv = NULL;
103 int i;
104 int fd;
105 char memory[10]; /* file descriptors to write to memory */
106
107 for (i = 10 ; --i >= 0 ; )
108 memory[i] = 0;
109 memory[1] = flags & REDIR_BACKQ;
110 if (flags & REDIR_PUSH) {
111 sv = ckmalloc(sizeof (struct redirtab));
112 for (i = 0 ; i < 10 ; i++)
113 sv->renamed[i] = EMPTY;
114 sv->next = redirlist;
115 redirlist = sv;
116 }
117 for (n = redir ; n ; n = n->nfile.next) {
118 fd = n->nfile.fd;
119 if ((n->nfile.type == NTOFD || n->nfile.type == NFROMFD) &&
120 n->ndup.dupfd == fd)
121 continue; /* redirect from/to same file descriptor */
122
123 if ((flags & REDIR_PUSH) && sv->renamed[fd] == EMPTY) {
124 INTOFF;
125 if ((i = fcntl(fd, F_DUPFD, 10)) == -1) {
126 switch (errno) {
127 case EBADF:
128 i = CLOSED;
129 break;
130 default:
131 INTON;
132 error("%d: %s", fd, strerror(errno));
133 break;
134 }
135 } else
136 (void)fcntl(i, F_SETFD, FD_CLOEXEC);
137 sv->renamed[fd] = i;
138 INTON;
139 }
140 if (fd == 0)
141 fd0_redirected++;
142 openredirect(n, memory);
143 }
144 if (memory[1])
145 out1 = &memout;
146 if (memory[2])
147 out2 = &memout;
148}
149
150
| 88
89
90/*
91 * Process a list of redirection commands. If the REDIR_PUSH flag is set,
92 * old file descriptors are stashed away so that the redirection can be
93 * undone by calling popredir. If the REDIR_BACKQ flag is set, then the
94 * standard output, and the standard error if it becomes a duplicate of
95 * stdout, is saved in memory.
96 */
97
98void
99redirect(union node *redir, int flags)
100{
101 union node *n;
102 struct redirtab *sv = NULL;
103 int i;
104 int fd;
105 char memory[10]; /* file descriptors to write to memory */
106
107 for (i = 10 ; --i >= 0 ; )
108 memory[i] = 0;
109 memory[1] = flags & REDIR_BACKQ;
110 if (flags & REDIR_PUSH) {
111 sv = ckmalloc(sizeof (struct redirtab));
112 for (i = 0 ; i < 10 ; i++)
113 sv->renamed[i] = EMPTY;
114 sv->next = redirlist;
115 redirlist = sv;
116 }
117 for (n = redir ; n ; n = n->nfile.next) {
118 fd = n->nfile.fd;
119 if ((n->nfile.type == NTOFD || n->nfile.type == NFROMFD) &&
120 n->ndup.dupfd == fd)
121 continue; /* redirect from/to same file descriptor */
122
123 if ((flags & REDIR_PUSH) && sv->renamed[fd] == EMPTY) {
124 INTOFF;
125 if ((i = fcntl(fd, F_DUPFD, 10)) == -1) {
126 switch (errno) {
127 case EBADF:
128 i = CLOSED;
129 break;
130 default:
131 INTON;
132 error("%d: %s", fd, strerror(errno));
133 break;
134 }
135 } else
136 (void)fcntl(i, F_SETFD, FD_CLOEXEC);
137 sv->renamed[fd] = i;
138 INTON;
139 }
140 if (fd == 0)
141 fd0_redirected++;
142 openredirect(n, memory);
143 }
144 if (memory[1])
145 out1 = &memout;
146 if (memory[2])
147 out2 = &memout;
148}
149
150
|
151STATIC void
| 151static void
|
152openredirect(union node *redir, char memory[10])
153{
154 struct stat sb;
155 int fd = redir->nfile.fd;
156 char *fname;
157 int f;
158
159 /*
160 * We suppress interrupts so that we won't leave open file
161 * descriptors around. Because the signal handler remains
162 * installed and we do not use system call restart, interrupts
163 * will still abort blocking opens such as fifos (they will fail
164 * with EINTR). There is, however, a race condition if an interrupt
165 * arrives after INTOFF and before open blocks.
166 */
167 INTOFF;
168 memory[fd] = 0;
169 switch (redir->nfile.type) {
170 case NFROM:
171 fname = redir->nfile.expfname;
172 if ((f = open(fname, O_RDONLY)) < 0)
173 error("cannot open %s: %s", fname, strerror(errno));
174movefd:
175 if (f != fd) {
176 dup2(f, fd);
177 close(f);
178 }
179 break;
180 case NFROMTO:
181 fname = redir->nfile.expfname;
182 if ((f = open(fname, O_RDWR|O_CREAT, 0666)) < 0)
183 error("cannot create %s: %s", fname, strerror(errno));
184 goto movefd;
185 case NTO:
186 if (Cflag) {
187 fname = redir->nfile.expfname;
188 if (stat(fname, &sb) == -1) {
189 if ((f = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0666)) < 0)
190 error("cannot create %s: %s", fname, strerror(errno));
191 } else if (!S_ISREG(sb.st_mode)) {
192 if ((f = open(fname, O_WRONLY, 0666)) < 0)
193 error("cannot create %s: %s", fname, strerror(errno));
194 if (fstat(f, &sb) != -1 && S_ISREG(sb.st_mode)) {
195 close(f);
196 error("cannot create %s: %s", fname,
197 strerror(EEXIST));
198 }
199 } else
200 error("cannot create %s: %s", fname,
201 strerror(EEXIST));
202 goto movefd;
203 }
204 /* FALLTHROUGH */
205 case NCLOBBER:
206 fname = redir->nfile.expfname;
207 if ((f = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) < 0)
208 error("cannot create %s: %s", fname, strerror(errno));
209 goto movefd;
210 case NAPPEND:
211 fname = redir->nfile.expfname;
212 if ((f = open(fname, O_WRONLY|O_CREAT|O_APPEND, 0666)) < 0)
213 error("cannot create %s: %s", fname, strerror(errno));
214 goto movefd;
215 case NTOFD:
216 case NFROMFD:
217 if (redir->ndup.dupfd >= 0) { /* if not ">&-" */
218 if (memory[redir->ndup.dupfd])
219 memory[fd] = 1;
220 else
221 dup2(redir->ndup.dupfd, fd);
222 } else {
223 close(fd);
224 }
225 break;
226 case NHERE:
227 case NXHERE:
228 f = openhere(redir);
229 goto movefd;
230 default:
231 abort();
232 }
233 INTON;
234}
235
236
237/*
238 * Handle here documents. Normally we fork off a process to write the
239 * data to a pipe. If the document is short, we can stuff the data in
240 * the pipe without forking.
241 */
242
| 152openredirect(union node *redir, char memory[10])
153{
154 struct stat sb;
155 int fd = redir->nfile.fd;
156 char *fname;
157 int f;
158
159 /*
160 * We suppress interrupts so that we won't leave open file
161 * descriptors around. Because the signal handler remains
162 * installed and we do not use system call restart, interrupts
163 * will still abort blocking opens such as fifos (they will fail
164 * with EINTR). There is, however, a race condition if an interrupt
165 * arrives after INTOFF and before open blocks.
166 */
167 INTOFF;
168 memory[fd] = 0;
169 switch (redir->nfile.type) {
170 case NFROM:
171 fname = redir->nfile.expfname;
172 if ((f = open(fname, O_RDONLY)) < 0)
173 error("cannot open %s: %s", fname, strerror(errno));
174movefd:
175 if (f != fd) {
176 dup2(f, fd);
177 close(f);
178 }
179 break;
180 case NFROMTO:
181 fname = redir->nfile.expfname;
182 if ((f = open(fname, O_RDWR|O_CREAT, 0666)) < 0)
183 error("cannot create %s: %s", fname, strerror(errno));
184 goto movefd;
185 case NTO:
186 if (Cflag) {
187 fname = redir->nfile.expfname;
188 if (stat(fname, &sb) == -1) {
189 if ((f = open(fname, O_WRONLY|O_CREAT|O_EXCL, 0666)) < 0)
190 error("cannot create %s: %s", fname, strerror(errno));
191 } else if (!S_ISREG(sb.st_mode)) {
192 if ((f = open(fname, O_WRONLY, 0666)) < 0)
193 error("cannot create %s: %s", fname, strerror(errno));
194 if (fstat(f, &sb) != -1 && S_ISREG(sb.st_mode)) {
195 close(f);
196 error("cannot create %s: %s", fname,
197 strerror(EEXIST));
198 }
199 } else
200 error("cannot create %s: %s", fname,
201 strerror(EEXIST));
202 goto movefd;
203 }
204 /* FALLTHROUGH */
205 case NCLOBBER:
206 fname = redir->nfile.expfname;
207 if ((f = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) < 0)
208 error("cannot create %s: %s", fname, strerror(errno));
209 goto movefd;
210 case NAPPEND:
211 fname = redir->nfile.expfname;
212 if ((f = open(fname, O_WRONLY|O_CREAT|O_APPEND, 0666)) < 0)
213 error("cannot create %s: %s", fname, strerror(errno));
214 goto movefd;
215 case NTOFD:
216 case NFROMFD:
217 if (redir->ndup.dupfd >= 0) { /* if not ">&-" */
218 if (memory[redir->ndup.dupfd])
219 memory[fd] = 1;
220 else
221 dup2(redir->ndup.dupfd, fd);
222 } else {
223 close(fd);
224 }
225 break;
226 case NHERE:
227 case NXHERE:
228 f = openhere(redir);
229 goto movefd;
230 default:
231 abort();
232 }
233 INTON;
234}
235
236
237/*
238 * Handle here documents. Normally we fork off a process to write the
239 * data to a pipe. If the document is short, we can stuff the data in
240 * the pipe without forking.
241 */
242
|
243STATIC int
| 243static int
|
244openhere(union node *redir)
245{
246 int pip[2];
247 int len = 0;
248
249 if (pipe(pip) < 0)
250 error("Pipe call failed: %s", strerror(errno));
251 if (redir->type == NHERE) {
252 len = strlen(redir->nhere.doc->narg.text);
253 if (len <= PIPESIZE) {
254 xwrite(pip[1], redir->nhere.doc->narg.text, len);
255 goto out;
256 }
257 }
258 if (forkshell((struct job *)NULL, (union node *)NULL, FORK_NOJOB) == 0) {
259 close(pip[0]);
260 signal(SIGINT, SIG_IGN);
261 signal(SIGQUIT, SIG_IGN);
262 signal(SIGHUP, SIG_IGN);
263 signal(SIGTSTP, SIG_IGN);
264 signal(SIGPIPE, SIG_DFL);
265 if (redir->type == NHERE)
266 xwrite(pip[1], redir->nhere.doc->narg.text, len);
267 else
268 expandhere(redir->nhere.doc, pip[1]);
269 _exit(0);
270 }
271out:
272 close(pip[1]);
273 return pip[0];
274}
275
276
277
278/*
279 * Undo the effects of the last redirection.
280 */
281
282void
283popredir(void)
284{
285 struct redirtab *rp = redirlist;
286 int i;
287
288 for (i = 0 ; i < 10 ; i++) {
289 if (rp->renamed[i] != EMPTY) {
290 if (i == 0)
291 fd0_redirected--;
292 if (rp->renamed[i] >= 0) {
293 dup2(rp->renamed[i], i);
294 close(rp->renamed[i]);
295 } else {
296 close(i);
297 }
298 }
299 }
300 INTOFF;
301 redirlist = rp->next;
302 ckfree(rp);
303 INTON;
304}
305
306/*
307 * Undo all redirections. Called on error or interrupt.
308 */
309
310#ifdef mkinit
311
312INCLUDE "redir.h"
313
314RESET {
315 while (redirlist)
316 popredir();
317}
318
319SHELLPROC {
320 clearredir();
321}
322
323#endif
324
325/* Return true if fd 0 has already been redirected at least once. */
326int
327fd0_redirected_p(void)
328{
329 return fd0_redirected != 0;
330}
331
332/*
333 * Discard all saved file descriptors.
334 */
335
336void
337clearredir(void)
338{
339 struct redirtab *rp;
340 int i;
341
342 for (rp = redirlist ; rp ; rp = rp->next) {
343 for (i = 0 ; i < 10 ; i++) {
344 if (rp->renamed[i] >= 0) {
345 close(rp->renamed[i]);
346 }
347 rp->renamed[i] = EMPTY;
348 }
349 }
350}
| 244openhere(union node *redir)
245{
246 int pip[2];
247 int len = 0;
248
249 if (pipe(pip) < 0)
250 error("Pipe call failed: %s", strerror(errno));
251 if (redir->type == NHERE) {
252 len = strlen(redir->nhere.doc->narg.text);
253 if (len <= PIPESIZE) {
254 xwrite(pip[1], redir->nhere.doc->narg.text, len);
255 goto out;
256 }
257 }
258 if (forkshell((struct job *)NULL, (union node *)NULL, FORK_NOJOB) == 0) {
259 close(pip[0]);
260 signal(SIGINT, SIG_IGN);
261 signal(SIGQUIT, SIG_IGN);
262 signal(SIGHUP, SIG_IGN);
263 signal(SIGTSTP, SIG_IGN);
264 signal(SIGPIPE, SIG_DFL);
265 if (redir->type == NHERE)
266 xwrite(pip[1], redir->nhere.doc->narg.text, len);
267 else
268 expandhere(redir->nhere.doc, pip[1]);
269 _exit(0);
270 }
271out:
272 close(pip[1]);
273 return pip[0];
274}
275
276
277
278/*
279 * Undo the effects of the last redirection.
280 */
281
282void
283popredir(void)
284{
285 struct redirtab *rp = redirlist;
286 int i;
287
288 for (i = 0 ; i < 10 ; i++) {
289 if (rp->renamed[i] != EMPTY) {
290 if (i == 0)
291 fd0_redirected--;
292 if (rp->renamed[i] >= 0) {
293 dup2(rp->renamed[i], i);
294 close(rp->renamed[i]);
295 } else {
296 close(i);
297 }
298 }
299 }
300 INTOFF;
301 redirlist = rp->next;
302 ckfree(rp);
303 INTON;
304}
305
306/*
307 * Undo all redirections. Called on error or interrupt.
308 */
309
310#ifdef mkinit
311
312INCLUDE "redir.h"
313
314RESET {
315 while (redirlist)
316 popredir();
317}
318
319SHELLPROC {
320 clearredir();
321}
322
323#endif
324
325/* Return true if fd 0 has already been redirected at least once. */
326int
327fd0_redirected_p(void)
328{
329 return fd0_redirected != 0;
330}
331
332/*
333 * Discard all saved file descriptors.
334 */
335
336void
337clearredir(void)
338{
339 struct redirtab *rp;
340 int i;
341
342 for (rp = redirlist ; rp ; rp = rp->next) {
343 for (i = 0 ; i < 10 ; i++) {
344 if (rp->renamed[i] >= 0) {
345 close(rp->renamed[i]);
346 }
347 rp->renamed[i] = EMPTY;
348 }
349 }
350}
|