progress.c revision 1.24 
1/*	$NetBSD: progress.c,v 1.24 2021/08/09 10:46:39 gson Exp $ */
2
3/*-
4 * Copyright (c) 2003 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by John Hawkinson.
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 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32#include <sys/cdefs.h>
33#ifndef lint
34__RCSID("$NetBSD: progress.c,v 1.24 2021/08/09 10:46:39 gson Exp $");
35#endif				/* not lint */
36
37#include <sys/types.h>
38#include <sys/ioctl.h>
39#include <sys/stat.h>
40#include <sys/wait.h>
41
42#include <err.h>
43#include <errno.h>
44#include <fcntl.h>
45#include <inttypes.h>
46#include <limits.h>
47#include <signal.h>
48#include <stdio.h>
49#include <stdlib.h>
50#include <string.h>
51#include <unistd.h>
52
53#define GLOBAL			/* force GLOBAL decls in progressbar.h to be
54				 * declared */
55#include "progressbar.h"
56
57static void broken_pipe(int unused);
58__dead static void usage(void);
59
60static void
61broken_pipe(int unused)
62{
63	signal(SIGPIPE, SIG_DFL);
64	progressmeter(1);
65	kill(getpid(), SIGPIPE);
66}
67
68static void
69usage(void)
70{
71	fprintf(stderr,
72	    "usage: %s [-ez] [-b buffersize] [-f file] [-l length]\n"
73	    "       %*.s [-p prefix] cmd [args...]\n",
74	    getprogname(), (int) strlen(getprogname()), "");
75	exit(EXIT_FAILURE);
76}
77
78int
79main(int argc, char *argv[])
80{
81	char *fb_buf;
82	char *infile = NULL;
83	pid_t pid = 0, gzippid = 0, deadpid;
84	int ch, fd, outpipe[2];
85	int ws, gzipstat, cmdstat;
86	int eflag = 0, lflag = 0, zflag = 0;
87	ssize_t nr, nw, off;
88	size_t buffersize;
89	struct stat statb;
90	struct ttysize ts;
91
92	setprogname(argv[0]);
93
94	/* defaults: Read from stdin, 0 filesize (no completion estimate) */
95	fd = STDIN_FILENO;
96	filesize = 0;
97	buffersize = 64 * 1024;
98	prefix = NULL;
99
100	while ((ch = getopt(argc, argv, "b:ef:l:p:z")) != -1)
101		switch (ch) {
102		case 'b':
103			buffersize = (size_t) strsuftoll("buffer size", optarg,
104			    0, SSIZE_MAX);
105			break;
106		case 'e':
107			eflag++;
108			break;
109		case 'f':
110			infile = optarg;
111			break;
112		case 'l':
113			lflag++;
114			filesize = strsuftoll("input size", optarg, 0,
115			    LLONG_MAX);
116			break;
117		case 'p':
118			prefix = optarg;
119			break;
120		case 'z':
121			zflag++;
122			break;
123		case '?':
124		default:
125			usage();
126			/* NOTREACHED */
127		}
128	argc -= optind;
129	argv += optind;
130
131	if (argc < 1)
132		usage();
133
134	if (infile && (fd = open(infile, O_RDONLY, 0)) < 0)
135		err(1, "%s", infile);
136
137	/* stat() to get the filesize unless overridden, or -z */
138	if (!zflag && !lflag && (fstat(fd, &statb) == 0)) {
139		if (S_ISFIFO(statb.st_mode)) {
140			/* stat(2) on pipe may return only the
141			 * first few bytes with more coming.
142			 * Don't trust!
143			 */
144		} else {
145			filesize = statb.st_size;
146		}
147	}
148
149	/* gzip -l the file if we have the name and -z is given */
150	if (zflag && !lflag && infile != NULL) {
151		FILE *gzipsizepipe;
152		char buf[256], *cp, *cmd;
153
154		/*
155		 * Read second word of last line of gzip -l output. Looks like:
156		 * % gzip -l ../etc.tgz
157		 *   compressed uncompressed  ratio uncompressed_name
158		 * 	 119737       696320  82.8% ../etc.tar
159		 */
160
161		asprintf(&cmd, "gzip -l %s", infile);
162		if ((gzipsizepipe = popen(cmd, "r")) == NULL)
163			err(1, "reading compressed file length");
164		for (; fgets(buf, 256, gzipsizepipe) != NULL;)
165		    continue;
166		strtoimax(buf, &cp, 10);
167		filesize = strtoimax(cp, NULL, 10);
168		if (pclose(gzipsizepipe) < 0)
169			err(1, "closing compressed file length pipe");
170		free(cmd);
171	}
172	/* Pipe input through gzip -dc if -z is given */
173	if (zflag) {
174		int gzippipe[2];
175
176		if (pipe(gzippipe) < 0)
177			err(1, "gzip pipe");
178		gzippid = fork();
179		if (gzippid < 0)
180			err(1, "fork for gzip");
181
182		if (gzippid) {
183			/* parent */
184			dup2(gzippipe[0], fd);
185			close(gzippipe[0]);
186			close(gzippipe[1]);
187		} else {
188			dup2(gzippipe[1], STDOUT_FILENO);
189			dup2(fd, STDIN_FILENO);
190			close(gzippipe[0]);
191			close(gzippipe[1]);
192			if (execlp("gzip", "gzip", "-dc", NULL))
193				err(1, "exec()ing gzip");
194		}
195	}
196
197	/* Initialize progressbar.c's global state */
198	bytes = 0;
199	progress = 1;
200	ttyout = eflag ? stderr : stdout;
201
202	if (ioctl(fileno(ttyout), TIOCGSIZE, &ts) == -1)
203		ttywidth = 80;
204	else
205		ttywidth = ts.ts_cols;
206
207	fb_buf = malloc(buffersize);
208	if (fb_buf == NULL)
209		err(1, "malloc for buffersize");
210
211	if (pipe(outpipe) < 0)
212		err(1, "output pipe");
213	pid = fork();
214	if (pid < 0)
215		err(1, "fork for output pipe");
216
217	if (pid == 0) {
218		/* child */
219		dup2(outpipe[0], STDIN_FILENO);
220		close(outpipe[0]);
221		close(outpipe[1]);
222		execvp(argv[0], argv);
223		err(1, "could not exec %s", argv[0]);
224	}
225	close(outpipe[0]);
226
227	signal(SIGPIPE, broken_pipe);
228	progressmeter(-1);
229
230	while (1) {
231		do {
232			nr = read(fd, fb_buf, buffersize);
233		} while (nr < 0 && errno == EINTR);
234		if (nr <= 0)
235			break;
236		for (off = 0; nr; nr -= nw, off += nw, bytes += nw)
237			if ((nw = write(outpipe[1], fb_buf + off,
238			    (size_t) nr)) < 0) {
239				if (errno == EINTR) {
240					nw = 0;
241					continue;
242				}
243				progressmeter(1);
244				err(1, "writing %u bytes to output pipe",
245							(unsigned) nr);
246			}
247	}
248	close(outpipe[1]);
249
250	gzipstat = 0;
251	cmdstat = 0;
252	while (pid || gzippid) {
253		deadpid = wait(&ws);
254		/*
255		 * We need to exit with an error if the command (or gzip)
256		 * exited abnormally.
257		 * Unfortunately we can't generate a true 'exited by signal'
258		 * error without sending the signal to ourselves :-(
259		 */
260		ws = WIFSIGNALED(ws) ? WTERMSIG(ws) : WEXITSTATUS(ws);
261
262		if (deadpid == -1 && errno == EINTR)
263			continue;
264		if (deadpid == pid) {
265			pid = 0;
266			cmdstat = ws;
267			continue;
268		}
269		if (deadpid == gzippid) {
270			gzippid = 0;
271			gzipstat = ws;
272			continue;
273		}
274		break;
275	}
276
277	progressmeter(1);
278	signal(SIGPIPE, SIG_DFL);
279
280	free(fb_buf);
281
282	exit(cmdstat ? cmdstat : gzipstat);
283}
284