output.c revision 216380 
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[] = "@(#)output.c	8.2 (Berkeley) 5/4/95";
36#endif
37#endif /* not lint */
38#include <sys/cdefs.h>
39__FBSDID("$FreeBSD: head/bin/sh/output.c 216380 2010-12-11 17:47:27Z jilles $");
40
41/*
42 * Shell output routines.  We use our own output routines because:
43 *	When a builtin command is interrupted we have to discard
44 *		any pending output.
45 *	When a builtin command appears in back quotes, we want to
46 *		save the output of the command in a region obtained
47 *		via malloc, rather than doing a fork and reading the
48 *		output of the command via a pipe.
49 */
50
51#include <stdio.h>	/* defines BUFSIZ */
52#include <string.h>
53#include <stdarg.h>
54#include <errno.h>
55#include <unistd.h>
56#include <stdlib.h>
57
58#include "shell.h"
59#include "syntax.h"
60#include "output.h"
61#include "memalloc.h"
62#include "error.h"
63#include "var.h"
64
65
66#define OUTBUFSIZ BUFSIZ
67#define MEM_OUT -2		/* output to dynamically allocated memory */
68#define OUTPUT_ERR 01		/* error occurred on output */
69
70static int doformat_wr(void *, const char *, int);
71
72struct output output = {NULL, 0, NULL, OUTBUFSIZ, 1, 0};
73struct output errout = {NULL, 0, NULL, 256, 2, 0};
74struct output memout = {NULL, 0, NULL, 0, MEM_OUT, 0};
75struct output *out1 = &output;
76struct output *out2 = &errout;
77
78
79
80#ifdef mkinit
81
82INCLUDE "output.h"
83INCLUDE "memalloc.h"
84
85RESET {
86	out1 = &output;
87	out2 = &errout;
88	if (memout.buf != NULL) {
89		ckfree(memout.buf);
90		memout.buf = NULL;
91	}
92}
93
94#endif
95
96
97void
98outcslow(int c, struct output *file)
99{
100	outc(c, file);
101}
102
103void
104out1str(const char *p)
105{
106	outstr(p, out1);
107}
108
109void
110out1qstr(const char *p)
111{
112	outqstr(p, out1);
113}
114
115void
116out2str(const char *p)
117{
118	outstr(p, out2);
119}
120
121void
122out2qstr(const char *p)
123{
124	outqstr(p, out2);
125}
126
127void
128outstr(const char *p, struct output *file)
129{
130	outbin(p, strlen(p), file);
131}
132
133/* Like outstr(), but quote for re-input into the shell. */
134void
135outqstr(const char *p, struct output *file)
136{
137	char ch;
138	int inquotes;
139
140	if (p[0] == '\0') {
141		outstr("''", file);
142		return;
143	}
144	/* Caller will handle '=' if necessary */
145	if (p[strcspn(p, "|&;<>()$`\\\"' \t\n*?[~#")] == '\0' ||
146			strcmp(p, "[") == 0) {
147		outstr(p, file);
148		return;
149	}
150
151	inquotes = 0;
152	while ((ch = *p++) != '\0') {
153		switch (ch) {
154		case '\'':
155			/* Can't quote single quotes inside single quotes. */
156			if (inquotes)
157				outcslow('\'', file);
158			inquotes = 0;
159			outstr("\\'", file);
160			break;
161		default:
162			if (!inquotes)
163				outcslow('\'', file);
164			inquotes = 1;
165			outc(ch, file);
166		}
167	}
168	if (inquotes)
169		outcslow('\'', file);
170}
171
172void
173outbin(const void *data, size_t len, struct output *file)
174{
175	const char *p;
176
177	p = data;
178	while (len-- > 0)
179		outc(*p++, file);
180}
181
182void
183emptyoutbuf(struct output *dest)
184{
185	int offset;
186
187	if (dest->buf == NULL) {
188		INTOFF;
189		dest->buf = ckmalloc(dest->bufsize);
190		dest->nextc = dest->buf;
191		dest->nleft = dest->bufsize;
192		INTON;
193	} else if (dest->fd == MEM_OUT) {
194		offset = dest->bufsize;
195		INTOFF;
196		dest->bufsize <<= 1;
197		dest->buf = ckrealloc(dest->buf, dest->bufsize);
198		dest->nleft = dest->bufsize - offset;
199		dest->nextc = dest->buf + offset;
200		INTON;
201	} else {
202		flushout(dest);
203	}
204	dest->nleft--;
205}
206
207
208void
209flushall(void)
210{
211	flushout(&output);
212	flushout(&errout);
213}
214
215
216void
217flushout(struct output *dest)
218{
219
220	if (dest->buf == NULL || dest->nextc == dest->buf || dest->fd < 0)
221		return;
222	if (xwrite(dest->fd, dest->buf, dest->nextc - dest->buf) < 0)
223		dest->flags |= OUTPUT_ERR;
224	dest->nextc = dest->buf;
225	dest->nleft = dest->bufsize;
226}
227
228
229void
230freestdout(void)
231{
232	INTOFF;
233	if (output.buf) {
234		ckfree(output.buf);
235		output.buf = NULL;
236		output.nleft = 0;
237	}
238	INTON;
239}
240
241
242void
243outfmt(struct output *file, const char *fmt, ...)
244{
245	va_list ap;
246
247	va_start(ap, fmt);
248	doformat(file, fmt, ap);
249	va_end(ap);
250}
251
252
253void
254out1fmt(const char *fmt, ...)
255{
256	va_list ap;
257
258	va_start(ap, fmt);
259	doformat(out1, fmt, ap);
260	va_end(ap);
261}
262
263void
264out2fmt_flush(const char *fmt, ...)
265{
266	va_list ap;
267
268	va_start(ap, fmt);
269	doformat(out2, fmt, ap);
270	va_end(ap);
271	flushout(out2);
272}
273
274void
275fmtstr(char *outbuf, int length, const char *fmt, ...)
276{
277	va_list ap;
278
279	INTOFF;
280	va_start(ap, fmt);
281	vsnprintf(outbuf, length, fmt, ap);
282	va_end(ap);
283	INTON;
284}
285
286static int
287doformat_wr(void *cookie, const char *buf, int len)
288{
289	struct output *o;
290
291	o = (struct output *)cookie;
292	outbin(buf, len, o);
293
294	return (len);
295}
296
297void
298doformat(struct output *dest, const char *f, va_list ap)
299{
300	FILE *fp;
301
302	if ((fp = fwopen(dest, doformat_wr)) != NULL) {
303		vfprintf(fp, f, ap);
304		fclose(fp);
305	}
306}
307
308/*
309 * Version of write which resumes after a signal is caught.
310 */
311
312int
313xwrite(int fd, const char *buf, int nbytes)
314{
315	int ntry;
316	int i;
317	int n;
318
319	n = nbytes;
320	ntry = 0;
321	for (;;) {
322		i = write(fd, buf, n);
323		if (i > 0) {
324			if ((n -= i) <= 0)
325				return nbytes;
326			buf += i;
327			ntry = 0;
328		} else if (i == 0) {
329			if (++ntry > 10)
330				return nbytes - n;
331		} else if (errno != EINTR) {
332			return -1;
333		}
334	}
335}
336