68 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			68 lines
		
	
	
		
			2.2 KiB
		
	
	
	
		
			C
		
	
	
	
| /*
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|  * Copyright (c) 2016 Dmitry V. Levin <ldv@altlinux.org>
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|  * All rights reserved.
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|  *
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|  * Redistribution and use in source and binary forms, with or without
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|  * modification, are permitted provided that the following conditions
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|  * are met:
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|  * 1. Redistributions of source code must retain the above copyright
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|  *    notice, this list of conditions and the following disclaimer.
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|  * 2. Redistributions in binary form must reproduce the above copyright
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|  *    notice, this list of conditions and the following disclaimer in the
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|  *    documentation and/or other materials provided with the distribution.
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|  * 3. The name of the author may not be used to endorse or promote products
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|  *    derived from this software without specific prior written permission.
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|  *
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|  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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|  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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|  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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|  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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|  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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|  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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|  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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|  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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|  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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|  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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|  */
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| 
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| #include "tests.h"
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| #include <limits.h>
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| #include <unistd.h>
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| #include <sys/resource.h>
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| 
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| static void
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| move_fd(int *from, int *to)
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| {
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| 	for (; *to > *from; --*to) {
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| 		if (dup2(*from, *to) != *to)
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| 			continue;
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| 		close(*from);
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| 		*from = *to;
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| 		break;
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| 	}
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| }
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| 
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| void
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| pipe_maxfd(int pipefd[2])
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| {
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| 	struct rlimit rlim;
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| 	if (getrlimit(RLIMIT_NOFILE, &rlim))
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| 		perror_msg_and_fail("getrlimit");
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| 	if (rlim.rlim_cur < rlim.rlim_max) {
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| 		struct rlimit rlim_new;
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| 		rlim_new.rlim_cur = rlim_new.rlim_max = rlim.rlim_max;
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| 		if (!setrlimit(RLIMIT_NOFILE, &rlim_new))
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| 			rlim.rlim_cur = rlim.rlim_max;
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| 	}
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| 
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| 	if (pipe(pipefd))
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| 		perror_msg_and_fail("pipe");
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| 
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| 	int max_fd = (rlim.rlim_cur > 0 && rlim.rlim_cur < INT_MAX)
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| 		     ? rlim.rlim_cur - 1 : INT_MAX;
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| 
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| 	move_fd(&pipefd[1], &max_fd);
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| 	--max_fd;
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| 	move_fd(&pipefd[0], &max_fd);
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| }
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