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/* vim: set sw=4 sts=4 et foldmethod=syntax : */
/*
* Copyright (c) 2007 Ciaran McCreesh
*
* This file is part of the Paludis package manager. Paludis is free software;
* you can redistribute it and/or modify it under the terms of the GNU General
* Public License version 2, as published by the Free Software Foundation.
*
* Paludis is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License along with
* this program; if not, write to the Free Software Foundation, Inc., 59 Temple
* Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <cstdlib>
#include <unistd.h>
#include <errno.h>
#include <string.h>
#include <iostream>
int
main(int argc, char *argv[])
{
if (argc != 3)
{
std::cerr << "Usage: " << argv[0] << " write_fd read_fd" << std::endl;
return EXIT_FAILURE;
}
int write_fd(std::atoi(argv[1])), read_fd(std::atoi(argv[2]));
if (0 != ::lockf(write_fd, F_LOCK, 0))
{
std::cerr << "Error: " << argv[0] << ": lockf failed with " << ::strerror(errno) << std::endl;
return EXIT_FAILURE;
}
/* copy stdin to the pipe read buffer */
char buf[1024];
int c, w;
while (((c = read(0, buf, 1024))) > 0)
{
char * buf_p(buf);
while (((w = write(write_fd, buf_p, c))) > 0)
{
buf_p += w;
c -= w;
if (c == 0)
break;
}
if (w == -1)
{
std::cerr << "Error: " << argv[0] << ": write failed with " << ::strerror(errno) << std::endl;
return EXIT_FAILURE;
}
}
if (c == -1)
{
std::cerr << "Error: " << argv[0] << ": read failed with " << ::strerror(errno) << std::endl;
return EXIT_FAILURE;
}
/* append null to the pipe read buffer */
buf[0] = '\0';
while (((w = write(write_fd, buf, 1))) == 0)
sleep(0);
if (w == -1)
{
std::cerr << "Error: " << argv[0] << ": write failed with " << ::strerror(errno) << std::endl;
return EXIT_FAILURE;
}
/* copy write buffer to stdout until we get a null, and discard that null */
while (((c = read(read_fd, buf, 1))) > 0)
{
if (buf[0] == '\0')
break;
while (((w = write(1, buf, c))) == 0)
sleep(0);
if (w == -1)
{
std::cerr << "Error: " << argv[0] << ": write failed with " << ::strerror(errno) << std::endl;
return EXIT_FAILURE;
}
}
if (c == -1)
{
std::cerr << "Error: " << argv[0] << ": read failed with " << ::strerror(errno) << std::endl;
return EXIT_FAILURE;
}
if (0 != ::lockf(write_fd, F_ULOCK, 0))
{
std::cerr << "Error: " << argv[0] << ": lockf unlock failed with " << ::strerror(errno) << std::endl;
return EXIT_FAILURE;
}
return EXIT_SUCCESS;
}
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