tee.c revision da2e3ebdc1edfbc5028edf1354e7dd2fa69a7968
/***********************************************************************
* *
* This software is part of the ast package *
* Copyright (c) 1992-2007 AT&T Knowledge Ventures *
* and is licensed under the *
* Common Public License, Version 1.0 *
* by AT&T Knowledge Ventures *
* *
* A copy of the License is available at *
* http://www.opensource.org/licenses/cpl1.0.txt *
* (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
* *
* Information and Software Systems Research *
* AT&T Research *
* Florham Park NJ *
* *
* Glenn Fowler <gsf@research.att.com> *
* David Korn <dgk@research.att.com> *
* *
***********************************************************************/
#pragma prototyped
/*
* David Korn
* AT&T Bell Laboratories
*
* tee
*/
static const char usage[] =
"[-?\n@(#)$Id: tee (AT&T Research) 2006-10-10 $\n]"
USAGE_LICENSE
"[+NAME?tee - duplicate standard input]"
"[+DESCRIPTION?\btee\b copies standard input to standard output "
"and to zero or more files. The options determine whether "
"the specified files are overwritten or appended to. The "
"\btee\b utility does not buffer output. If writes to any "
"\afile\a fail, writes to other files continue although \btee\b "
"will exit with a non-zero exit status.]"
"[+?The number of \afile\a operands that can be specified is limited "
"by the underlying operating system.]"
"[a:append?Append the standard input to the given files rather "
"than overwriting them.]"
"[i:ignore-interrupts?Ignore SIGINT signal.]"
"[l:linebuffer?Set the standard output to be line buffered.]"
"\n"
"\n[file ...]\n"
"\n"
"[+EXIT STATUS?]{"
"[+0?All files copies successfully.]"
"[+>0?An error occurred.]"
"}"
"[+SEE ALSO?\bcat\b(1), \bsignal\b(3)]"
;
#include <cmd.h>
#include <ls.h>
#include <sig.h>
typedef struct Tee_s
{
Sfdisc_t disc;
int fd[1];
} Tee_t;
/*
* This discipline writes to each file in the list given in handle
*/
static ssize_t tee_write(Sfio_t* fp, const void* buf, size_t n, Sfdisc_t* handle)
{
register const char* bp;
register const char* ep;
register int* hp = ((Tee_t*)handle)->fd;
register int fd = sffileno(fp);
register ssize_t r;
do
{
bp = (const char*)buf;
ep = bp + n;
while (bp < ep)
{
if ((r = write(fd, bp, ep - bp)) <= 0)
return(-1);
bp += r;
}
} while ((fd = *hp++) >= 0);
return(n);
}
int
b_tee(int argc, register char** argv, void* context)
{
register Tee_t* tp = 0;
register int oflag = O_WRONLY|O_TRUNC|O_CREAT|O_BINARY;
register int n;
register int* hp;
register char* cp;
int line;
Sfdisc_t tee_disc;
cmdinit(argc, argv, context, ERROR_CATALOG, 0);
line = -1;
while (n = optget(argv, usage)) switch (n)
{
case 'a':
oflag &= ~O_TRUNC;
oflag |= O_APPEND;
break;
case 'i':
signal(SIGINT, SIG_IGN);
break;
case 'l':
line = sfset(sfstdout, 0, 0) & SF_LINE;
if ((line == 0) == (opt_info.num == 0))
line = -1;
else
sfset(sfstdout, SF_LINE, !!opt_info.num);
break;
case ':':
error(2, "%s", opt_info.arg);
break;
case '?':
error(ERROR_usage(2), "%s", opt_info.arg);
break;
}
if(error_info.errors)
error(ERROR_usage(2), "%s", optusage(NiL));
argv += opt_info.index;
argc -= opt_info.index;
/*
* for backward compatibility
*/
if (*argv && streq(*argv, "-"))
{
signal(SIGINT, SIG_IGN);
argv++;
argc--;
}
if (argc > 0)
{
if (!(tp = (Tee_t*)stakalloc(sizeof(Tee_t) + argc * sizeof(int))))
error(ERROR_exit(1), "no space");
memset(&tee_disc, 0, sizeof(tee_disc));
tee_disc.writef = tee_write;
tp->disc = tee_disc;
hp = tp->fd;
while (cp = *argv++)
{
if ((*hp = open(cp, oflag, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH)) < 0)
error(ERROR_system(0), "%s: cannot create", cp);
else hp++;
}
if (hp == tp->fd)
tp = 0;
else
{
*hp = -1;
sfdisc(sfstdout, &tp->disc);
}
}
if (sfmove(sfstdin, sfstdout, SF_UNBOUND, -1) < 0 || !sfeof(sfstdin) || sfsync(sfstdout))
error(ERROR_system(1), "cannot copy");
/*
* close files and free resources
*/
if (tp)
{
sfdisc(sfstdout, NiL);
if (line >= 0)
sfset(sfstdout, SF_LINE, line);
for(hp = tp->fd; (n = *hp) >= 0; hp++)
close(n);
}
return(error_info.errors);
}