GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libc/stdlib/posix_pty.c Lines: 0 31 0.0 %
Date: 2017-11-13 Branches: 0 16 0.0 %

Line Branch Exec Source
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/*	$OpenBSD: posix_pty.c,v 1.2 2015/05/11 00:42:54 guenther Exp $	*/
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/*
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 * Copyright (c) 2012 Todd C. Miller <Todd.Miller@courtesan.com>
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 *
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 * Permission to use, copy, modify, and distribute this software for any
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 * purpose with or without fee is hereby granted, provided that the above
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 * copyright notice and this permission notice appear in all copies.
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 *
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 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
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 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
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 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
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 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
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 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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 */
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#include <sys/types.h>
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#include <sys/ioctl.h>
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#include <sys/stat.h>
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#include <sys/tty.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <paths.h>
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#include <stddef.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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int
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posix_openpt(int oflag)
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{
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	struct ptmget ptm;
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	int fd, mfd = -1;
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	/* User must specify O_RDWR in oflag. */
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	if ((oflag & O_ACCMODE) != O_RDWR ||
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	    (oflag & ~(O_ACCMODE | O_NOCTTY)) != 0) {
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		errno = EINVAL;
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		return -1;
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	}
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	/* Get pty master and slave (this API only uses the master). */
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	fd = open(PATH_PTMDEV, O_RDWR);
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	if (fd != -1) {
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		if (ioctl(fd, PTMGET, &ptm) != -1) {
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			close(ptm.sfd);
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			mfd = ptm.cfd;
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		}
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		close(fd);
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	}
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	return mfd;
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}
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/*
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 * Look up the name of the specified pty master fd.
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 * Note that the name returned does *not* include the /dev/ prefix.
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 * Returns the name on success and NULL on error, setting errno.
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 */
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static const char *
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ptmname(int mfd)
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{
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	struct stat sb;
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	const char *name;
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	/* Make sure it is a pty master. */
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	if (fstat(mfd, &sb) != 0)
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		return NULL;
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	if (!S_ISCHR(sb.st_mode)) {
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		errno = EINVAL;
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		return NULL;
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	}
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	name = devname(sb.st_rdev, S_IFCHR);
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	if (strncmp(name, "pty", 3) != 0) {
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		errno = EINVAL;
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		return NULL;
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	}
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	return name;
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}
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/*
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 * The PTMGET ioctl handles the mode and owner for us.
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 */
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int
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grantpt(int mfd)
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{
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	return ptmname(mfd) ? 0 : -1;
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}
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/*
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 * The PTMGET ioctl unlocks the pty master and slave for us.
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 */
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int
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unlockpt(int mfd)
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{
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	return ptmname(mfd) ? 0 : -1;
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}
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/*
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 * Look up the path of the slave pty that corresponds to the master fd.
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 * Returns the path if successful or NULL on error.
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 */
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char *
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ptsname(int mfd)
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{
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	const char *master;
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	static char slave[sizeof(((struct ptmget *)NULL)->sn)];
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	if ((master = ptmname(mfd)) == NULL)
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		return NULL;
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	/* Add /dev/ prefix and convert "pty" to "tty". */
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	strlcpy(slave, _PATH_DEV, sizeof(slave));
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	strlcat(slave, master, sizeof(slave));
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	slave[sizeof(_PATH_DEV) - 1] = 't';
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	return slave;
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}