output.c revision 194516 
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 194516 2009-06-19 22:09:55Z 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 BLOCK_OUT -2		/* output to a fixed block of memory */
68#define MEM_OUT -3		/* output to dynamically allocated memory */
69#define OUTPUT_ERR 01		/* error occurred on output */
70
71static int doformat_wr(void *, const char *, int);
72
73struct output output = {NULL, 0, NULL, OUTBUFSIZ, 1, 0};
74struct output errout = {NULL, 0, NULL, 100, 2, 0};
75struct output memout = {NULL, 0, NULL, 0, MEM_OUT, 0};
76struct output *out1 = &output;
77struct output *out2 = &errout;
78
79
80
81#ifdef mkinit
82
83INCLUDE "output.h"
84INCLUDE "memalloc.h"
85
86RESET {
87	out1 = &output;
88	out2 = &errout;
89	if (memout.buf != NULL) {
90		ckfree(memout.buf);
91		memout.buf = NULL;
92	}
93}
94
95#endif
96
97
98void
99out1str(const char *p)
100{
101	outstr(p, out1);
102}
103
104void
105out1qstr(const char *p)
106{
107	outqstr(p, out1);
108}
109
110void
111out2str(const char *p)
112{
113	outstr(p, out2);
114}
115
116void
117out2qstr(const char *p)
118{
119	outqstr(p, out2);
120}
121
122void
123outstr(const char *p, struct output *file)
124{
125	while (*p)
126		outc(*p++, file);
127	if (file == out2)
128		flushout(file);
129}
130
131/* Like outstr(), but quote for re-input into the shell. */
132void
133outqstr(const char *p, struct output *file)
134{
135	char ch;
136	int inquotes;
137
138	if (p[0] == '\0') {
139		outstr("''", file);
140		return;
141	}
142	/* Caller will handle '=' if necessary */
143	if (p[strcspn(p, "|&;<>()$`\\\"' \t\n*?[~#")] == '\0' ||
144			strcmp(p, "[") == 0) {
145		outstr(p, file);
146		return;
147	}
148
149	inquotes = 0;
150	while ((ch = *p++) != '\0') {
151		switch (ch) {
152		case '\'':
153			/* Can't quote single quotes inside single quotes. */
154			if (inquotes)
155				outc('\'', file);
156			inquotes = 0;
157			outstr("\\'", file);
158			break;
159		default:
160			if (!inquotes)
161				outc('\'', file);
162			inquotes = 1;
163			outc(ch, file);
164		}
165	}
166	if (inquotes)
167		outc('\'', file);
168}
169
170STATIC char out_junk[16];
171
172void
173emptyoutbuf(struct output *dest)
174{
175	int offset;
176
177	if (dest->fd == BLOCK_OUT) {
178		dest->nextc = out_junk;
179		dest->nleft = sizeof out_junk;
180		dest->flags |= OUTPUT_ERR;
181	} else if (dest->buf == NULL) {
182		INTOFF;
183		dest->buf = ckmalloc(dest->bufsize);
184		dest->nextc = dest->buf;
185		dest->nleft = dest->bufsize;
186		INTON;
187	} else if (dest->fd == MEM_OUT) {
188		offset = dest->bufsize;
189		INTOFF;
190		dest->bufsize <<= 1;
191		dest->buf = ckrealloc(dest->buf, dest->bufsize);
192		dest->nleft = dest->bufsize - offset;
193		dest->nextc = dest->buf + offset;
194		INTON;
195	} else {
196		flushout(dest);
197	}
198	dest->nleft--;
199}
200
201
202void
203flushall(void)
204{
205	flushout(&output);
206	flushout(&errout);
207}
208
209
210void
211flushout(struct output *dest)
212{
213
214	if (dest->buf == NULL || dest->nextc == dest->buf || dest->fd < 0)
215		return;
216	if (xwrite(dest->fd, dest->buf, dest->nextc - dest->buf) < 0)
217		dest->flags |= OUTPUT_ERR;
218	dest->nextc = dest->buf;
219	dest->nleft = dest->bufsize;
220}
221
222
223void
224freestdout(void)
225{
226	INTOFF;
227	if (output.buf) {
228		ckfree(output.buf);
229		output.buf = NULL;
230		output.nleft = 0;
231	}
232	INTON;
233}
234
235
236void
237outfmt(struct output *file, const char *fmt, ...)
238{
239	va_list ap;
240
241	va_start(ap, fmt);
242	doformat(file, fmt, ap);
243	va_end(ap);
244}
245
246
247void
248out1fmt(const char *fmt, ...)
249{
250	va_list ap;
251
252	va_start(ap, fmt);
253	doformat(out1, fmt, ap);
254	va_end(ap);
255}
256
257void
258dprintf(const char *fmt, ...)
259{
260	va_list ap;
261
262	va_start(ap, fmt);
263	doformat(out2, fmt, ap);
264	va_end(ap);
265	flushout(out2);
266}
267
268void
269fmtstr(char *outbuf, int length, const char *fmt, ...)
270{
271	va_list ap;
272	struct output strout;
273
274	strout.nextc = outbuf;
275	strout.nleft = length;
276	strout.fd = BLOCK_OUT;
277	strout.flags = 0;
278	va_start(ap, fmt);
279	doformat(&strout, fmt, ap);
280	va_end(ap);
281	outc('\0', &strout);
282	if (strout.flags & OUTPUT_ERR)
283		outbuf[length - 1] = '\0';
284}
285
286static int
287doformat_wr(void *cookie, const char *buf, int len)
288{
289	struct output *o;
290	int origlen;
291	unsigned char c;
292
293	o = (struct output *)cookie;
294	origlen = len;
295	while (len-- != 0) {
296		c = (unsigned char)*buf++;
297		outc(c, o);
298	}
299
300	return (origlen);
301}
302
303void
304doformat(struct output *dest, const char *f, va_list ap)
305{
306	FILE *fp;
307
308	if ((fp = fwopen(dest, doformat_wr)) != NULL) {
309		vfprintf(fp, f, ap);
310		fclose(fp);
311	}
312}
313
314/*
315 * Version of write which resumes after a signal is caught.
316 */
317
318int
319xwrite(int fd, char *buf, int nbytes)
320{
321	int ntry;
322	int i;
323	int n;
324
325	n = nbytes;
326	ntry = 0;
327	for (;;) {
328		i = write(fd, buf, n);
329		if (i > 0) {
330			if ((n -= i) <= 0)
331				return nbytes;
332			buf += i;
333			ntry = 0;
334		} else if (i == 0) {
335			if (++ntry > 10)
336				return nbytes - n;
337		} else if (errno != EINTR) {
338			return -1;
339		}
340	}
341}
342