xref: /titanic_41/usr/src/lib/libcmd/common/tee.c (revision a31148363f598def767ac48c5d82e1572e44b935)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1992-2009 AT&T Intellectual Property          *
5 *                      and is licensed under the                       *
6 *                  Common Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12 *                                                                      *
13 *              Information and Software Systems Research               *
14 *                            AT&T Research                             *
15 *                           Florham Park NJ                            *
16 *                                                                      *
17 *                 Glenn Fowler <gsf@research.att.com>                  *
18 *                  David Korn <dgk@research.att.com>                   *
19 *                                                                      *
20 ***********************************************************************/
21 #pragma prototyped
22 /*
23  * David Korn
24  * AT&T Bell Laboratories
25  *
26  * tee
27  */
28 
29 static const char usage[] =
30 "[-?\n@(#)$Id: tee (AT&T Research) 2009-06-19 $\n]"
31 USAGE_LICENSE
32 "[+NAME?tee - duplicate standard input]"
33 "[+DESCRIPTION?\btee\b copies standard input to standard output "
34 	"and to zero or more files.  The options determine whether "
35 	"the specified files are overwritten or appended to.  The "
36 	"\btee\b utility does not buffer output.  If writes to any "
37 	"\afile\a fail, writes to other files continue although \btee\b "
38 	"will exit with a non-zero exit status.]"
39 "[+?The number of \afile\a operands that can be specified is limited "
40 	"by the underlying operating system.]"
41 "[a:append?Append the standard input to the given files rather "
42 	"than overwriting them.]"
43 "[i:ignore-interrupts?Ignore SIGINT signal.]"
44 "[l:linebuffer?Set the standard output to be line buffered.]"
45 "\n"
46 "\n[file ...]\n"
47 "\n"
48 "[+EXIT STATUS?]{"
49         "[+0?All files copies successfully.]"
50         "[+>0?An error occurred.]"
51 "}"
52 "[+SEE ALSO?\bcat\b(1), \bsignal\b(3)]"
53 ;
54 
55 #include <cmd.h>
56 #include <ls.h>
57 #include <sig.h>
58 
59 typedef struct Tee_s
60 {
61 	Sfdisc_t	disc;
62 	int		line;
63 	int		fd[1];
64 } Tee_t;
65 
66 /*
67  * This discipline writes to each file in the list given in handle
68  */
69 
70 static ssize_t
71 tee_write(Sfio_t* fp, const void* buf, size_t n, Sfdisc_t* handle)
72 {
73 	register const char*	bp;
74 	register const char*	ep;
75 	register int*		hp = ((Tee_t*)handle)->fd;
76 	register int		fd = sffileno(fp);
77 	register ssize_t	r;
78 
79 	do
80 	{
81 		bp = (const char*)buf;
82 		ep = bp + n;
83 		while (bp < ep)
84 		{
85 			if ((r = write(fd, bp, ep - bp)) <= 0)
86 				return -1;
87 			bp += r;
88 		}
89 	} while ((fd = *hp++) >= 0);
90 	return n;
91 }
92 
93 static void
94 tee_cleanup(register Tee_t* tp)
95 {
96 	register int*	hp;
97 	register int	n;
98 
99 	if (tp)
100 	{
101 		sfdisc(sfstdout, NiL);
102 		if (tp->line >= 0)
103 			sfset(sfstdout, SF_LINE, tp->line);
104 		for (hp = tp->fd; (n = *hp) >= 0; hp++)
105 			close(n);
106 	}
107 }
108 
109 int
110 b_tee(int argc, register char** argv, void* context)
111 {
112 	register Tee_t*		tp = 0;
113 	register int		oflag = O_WRONLY|O_TRUNC|O_CREAT|O_BINARY;
114 	register int		n;
115 	register int*		hp;
116 	register char*		cp;
117 	int			line;
118 	Sfdisc_t		tee_disc;
119 
120 	if (argc <= 0)
121 	{
122 		if (context && (tp = (Tee_t*)sh_context(context)->data))
123 		{
124 			sh_context(context)->data = 0;
125 			tee_cleanup(tp);
126 		}
127 		return 0;
128 	}
129 	cmdinit(argc, argv, context, ERROR_CATALOG, ERROR_CALLBACK);
130 	line = -1;
131 	for (;;)
132 	{
133 		switch (optget(argv, usage))
134 		{
135 		case 'a':
136 			oflag &= ~O_TRUNC;
137 			oflag |= O_APPEND;
138 			continue;
139 		case 'i':
140 			signal(SIGINT, SIG_IGN);
141 			continue;
142 		case 'l':
143 			line = sfset(sfstdout, 0, 0) & SF_LINE;
144 			if ((line == 0) == (opt_info.num == 0))
145 				line = -1;
146 			else
147 				sfset(sfstdout, SF_LINE, !!opt_info.num);
148 			continue;
149 		case ':':
150 			error(2, "%s", opt_info.arg);
151 			break;
152 		case '?':
153 			error(ERROR_usage(2), "%s", opt_info.arg);
154 			break;
155 		}
156 		break;
157 	}
158 	if (error_info.errors)
159 		error(ERROR_usage(2), "%s", optusage(NiL));
160 	argv += opt_info.index;
161 	argc -= opt_info.index;
162 #if _ANCIENT_BSD_COMPATIBILITY
163 	if (*argv && streq(*argv, "-"))
164 	{
165 		signal(SIGINT, SIG_IGN);
166 		argv++;
167 		argc--;
168 	}
169 #endif
170 	if (argc > 0)
171 	{
172 		if (tp = (Tee_t*)stakalloc(sizeof(Tee_t) + argc * sizeof(int)))
173 		{
174 			memset(&tp->disc, 0, sizeof(tp->disc));
175 			tp->disc.writef = tee_write;
176 			if (context)
177 				sh_context(context)->data = (void*)tp;
178 			tp->line = line;
179 			hp = tp->fd;
180 			while (cp = *argv++)
181 			{
182 				if ((*hp = open(cp, oflag, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH)) < 0)
183 					error(ERROR_system(0), "%s: cannot create", cp);
184 				else
185 					hp++;
186 			}
187 			if (hp == tp->fd)
188 				tp = 0;
189 			else
190 			{
191 				*hp = -1;
192 				sfdisc(sfstdout, &tp->disc);
193 			}
194 		}
195 		else
196 			error(ERROR_exit(0), "out of space");
197 	}
198 	if ((sfmove(sfstdin, sfstdout, SF_UNBOUND, -1) < 0 || !sfeof(sfstdin)) && errno != EPIPE)
199 		error(ERROR_system(0), "read error");
200 	if (sfsync(sfstdout))
201 		error(ERROR_system(0), "write error");
202 	tee_cleanup(tp);
203 	return error_info.errors;
204 }
205