x86_64: Function renaming lapic_init -> lapic_map
[dragonfly.git] / bin / sh / redir.c
CommitLineData
984263bc
MD
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 * 3. All advertising materials mentioning features or use of this software
17 * must display the following acknowledgement:
18 * This product includes software developed by the University of
19 * California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 * may be used to endorse or promote products derived from this software
22 * without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
1de703da
MD
35 *
36 * @(#)redir.c 8.2 (Berkeley) 5/4/95
996bd0d6
PA
37 * $FreeBSD: src/bin/sh/redir.c,v 1.26 2004/04/06 20:06:51 markm Exp $
38 * $DragonFly: src/bin/sh/redir.c,v 1.5 2007/01/14 05:48:08 pavalos Exp $
984263bc
MD
39 */
40
984263bc
MD
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 PIPESIZE 4096 /* amount of buffering in a pipe */
67
68
69MKINIT
70struct redirtab {
71 struct redirtab *next;
72 int renamed[10];
73};
74
75
76MKINIT struct redirtab *redirlist;
77
78/*
79 * We keep track of whether or not fd0 has been redirected. This is for
80 * background commands, where we want to redirect fd0 to /dev/null only
81 * if it hasn't already been redirected.
82*/
f8903466 83STATIC int fd0_redirected = 0;
984263bc
MD
84
85STATIC void openredirect(union node *, char[10 ]);
86STATIC int openhere(union node *);
87
88
89/*
90 * Process a list of redirection commands. If the REDIR_PUSH flag is set,
91 * old file descriptors are stashed away so that the redirection can be
92 * undone by calling popredir. If the REDIR_BACKQ flag is set, then the
93 * standard output, and the standard error if it becomes a duplicate of
94 * stdout, is saved in memory.
95 */
96
97void
98redirect(union node *redir, int flags)
99{
100 union node *n;
101 struct redirtab *sv = NULL;
102 int i;
103 int fd;
104 int try;
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 try = 0;
120 if ((n->nfile.type == NTOFD || n->nfile.type == NFROMFD) &&
121 n->ndup.dupfd == fd)
122 continue; /* redirect from/to same file descriptor */
123
124 if ((flags & REDIR_PUSH) && sv->renamed[fd] == EMPTY) {
125 INTOFF;
126again:
127 if ((i = fcntl(fd, F_DUPFD, 10)) == -1) {
128 switch (errno) {
129 case EBADF:
130 if (!try) {
131 openredirect(n, memory);
132 try++;
133 goto again;
134 }
135 /* FALLTHROUGH*/
136 default:
137 INTON;
138 error("%d: %s", fd, strerror(errno));
139 break;
140 }
141 }
142 if (!try) {
143 sv->renamed[fd] = i;
144 }
145 INTON;
146 }
147 if (fd == 0)
148 fd0_redirected++;
149 if (!try)
150 openredirect(n, memory);
151 }
152 if (memory[1])
153 out1 = &memout;
154 if (memory[2])
155 out2 = &memout;
156}
157
158
159STATIC void
160openredirect(union node *redir, char memory[10])
161{
162 struct stat sb;
163 int fd = redir->nfile.fd;
164 char *fname;
165 int f;
166
167 /*
168 * We suppress interrupts so that we won't leave open file
169 * descriptors around. This may not be such a good idea because
170 * an open of a device or a fifo can block indefinitely.
171 */
172 INTOFF;
173 memory[fd] = 0;
174 switch (redir->nfile.type) {
175 case NFROM:
176 fname = redir->nfile.expfname;
177 if ((f = open(fname, O_RDONLY)) < 0)
010f7689 178 error("cannot open %s: %s", fname, strerror(errno));
984263bc
MD
179movefd:
180 if (f != fd) {
996bd0d6 181 dup2(f, fd);
984263bc
MD
182 close(f);
183 }
184 break;
185 case NFROMTO:
186 fname = redir->nfile.expfname;
984263bc 187 if ((f = open(fname, O_RDWR|O_CREAT, 0666)) < 0)
010f7689 188 error("cannot create %s: %s", fname, strerror(errno));
984263bc
MD
189 goto movefd;
190 case NTO:
191 fname = redir->nfile.expfname;
192 if (Cflag && stat(fname, &sb) != -1 && S_ISREG(sb.st_mode))
193 error("cannot create %s: %s", fname,
010f7689 194 strerror(EEXIST));
984263bc 195 if ((f = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) < 0)
010f7689 196 error("cannot create %s: %s", fname, strerror(errno));
984263bc
MD
197 goto movefd;
198 case NCLOBBER:
199 fname = redir->nfile.expfname;
200 if ((f = open(fname, O_WRONLY|O_CREAT|O_TRUNC, 0666)) < 0)
010f7689 201 error("cannot create %s: %s", fname, strerror(errno));
984263bc
MD
202 goto movefd;
203 case NAPPEND:
204 fname = redir->nfile.expfname;
984263bc 205 if ((f = open(fname, O_WRONLY|O_CREAT|O_APPEND, 0666)) < 0)
010f7689 206 error("cannot create %s: %s", fname, strerror(errno));
984263bc
MD
207 goto movefd;
208 case NTOFD:
209 case NFROMFD:
210 if (redir->ndup.dupfd >= 0) { /* if not ">&-" */
211 if (memory[redir->ndup.dupfd])
212 memory[fd] = 1;
996bd0d6
PA
213 else
214 dup2(redir->ndup.dupfd, fd);
215 } else {
984263bc 216 close(fd);
996bd0d6 217 }
984263bc
MD
218 break;
219 case NHERE:
220 case NXHERE:
221 f = openhere(redir);
222 goto movefd;
223 default:
224 abort();
225 }
226 INTON;
227}
228
229
230/*
231 * Handle here documents. Normally we fork off a process to write the
232 * data to a pipe. If the document is short, we can stuff the data in
233 * the pipe without forking.
234 */
235
236STATIC int
237openhere(union node *redir)
238{
239 int pip[2];
240 int len = 0;
241
242 if (pipe(pip) < 0)
243 error("Pipe call failed: %s", strerror(errno));
244 if (redir->type == NHERE) {
245 len = strlen(redir->nhere.doc->narg.text);
246 if (len <= PIPESIZE) {
247 xwrite(pip[1], redir->nhere.doc->narg.text, len);
248 goto out;
249 }
250 }
2038fb68 251 if (forkshell(NULL, NULL, FORK_NOJOB) == 0) {
984263bc
MD
252 close(pip[0]);
253 signal(SIGINT, SIG_IGN);
254 signal(SIGQUIT, SIG_IGN);
255 signal(SIGHUP, SIG_IGN);
984263bc 256 signal(SIGTSTP, SIG_IGN);
984263bc
MD
257 signal(SIGPIPE, SIG_DFL);
258 if (redir->type == NHERE)
259 xwrite(pip[1], redir->nhere.doc->narg.text, len);
260 else
261 expandhere(redir->nhere.doc, pip[1]);
262 _exit(0);
263 }
264out:
265 close(pip[1]);
266 return pip[0];
267}
268
269
270
271/*
272 * Undo the effects of the last redirection.
273 */
274
275void
276popredir(void)
277{
278 struct redirtab *rp = redirlist;
279 int i;
280
281 for (i = 0 ; i < 10 ; i++) {
282 if (rp->renamed[i] != EMPTY) {
283 if (i == 0)
284 fd0_redirected--;
984263bc 285 if (rp->renamed[i] >= 0) {
996bd0d6 286 dup2(rp->renamed[i], i);
984263bc 287 close(rp->renamed[i]);
996bd0d6
PA
288 } else {
289 close(i);
984263bc
MD
290 }
291 }
292 }
293 INTOFF;
294 redirlist = rp->next;
295 ckfree(rp);
296 INTON;
297}
298
299/*
300 * Undo all redirections. Called on error or interrupt.
301 */
302
303#ifdef mkinit
304
305INCLUDE "redir.h"
306
307RESET {
308 while (redirlist)
309 popredir();
310}
311
312SHELLPROC {
313 clearredir();
314}
315
316#endif
317
318/* Return true if fd 0 has already been redirected at least once. */
319int
320fd0_redirected_p(void)
321{
322 return fd0_redirected != 0;
323}
324
325/*
326 * Discard all saved file descriptors.
327 */
328
329void
330clearredir(void)
331{
332 struct redirtab *rp;
333 int i;
334
335 for (rp = redirlist ; rp ; rp = rp->next) {
336 for (i = 0 ; i < 10 ; i++) {
337 if (rp->renamed[i] >= 0) {
338 close(rp->renamed[i]);
339 }
340 rp->renamed[i] = EMPTY;
341 }
342 }
343}