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Diffstat (limited to 'REORG.TODO/login/openpty.c')
| -rw-r--r-- | REORG.TODO/login/openpty.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/REORG.TODO/login/openpty.c b/REORG.TODO/login/openpty.c new file mode 100644 index 0000000000..41ab0483e2 --- /dev/null +++ b/REORG.TODO/login/openpty.c @@ -0,0 +1,140 @@ +/* Copyright (C) 1998-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Zack Weinberg <zack@rabi.phys.columbia.edu>, 1998. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <http://www.gnu.org/licenses/>. */ + +#include <errno.h> +#include <fcntl.h> +#include <limits.h> +#include <pty.h> +#include <stdlib.h> +#include <string.h> +#include <termios.h> +#include <unistd.h> +#include <sys/types.h> + + +/* Return the result of ptsname_r in the buffer pointed to by PTS, + which should be of length BUF_LEN. If it is too long to fit in + this buffer, a sufficiently long buffer is allocated using malloc, + and returned in PTS. 0 is returned upon success, -1 otherwise. */ +static int +pts_name (int fd, char **pts, size_t buf_len) +{ + int rv; + char *buf = *pts; + + for (;;) + { + char *new_buf; + + if (buf_len) + { + rv = ptsname_r (fd, buf, buf_len); + + if (rv != 0 || memchr (buf, '\0', buf_len)) + /* We either got an error, or we succeeded and the + returned name fit in the buffer. */ + break; + + /* Try again with a longer buffer. */ + buf_len += buf_len; /* Double it */ + } + else + /* No initial buffer; start out by mallocing one. */ + buf_len = 128; /* First time guess. */ + + if (buf != *pts) + /* We've already malloced another buffer at least once. */ + new_buf = realloc (buf, buf_len); + else + new_buf = malloc (buf_len); + if (! new_buf) + { + rv = -1; + __set_errno (ENOMEM); + break; + } + buf = new_buf; + } + + if (rv == 0) + *pts = buf; /* Return buffer to the user. */ + else if (buf != *pts) + free (buf); /* Free what we malloced when returning an error. */ + + return rv; +} + +/* Create pseudo tty master slave pair and set terminal attributes + according to TERMP and WINP. Return handles for both ends in + AMASTER and ASLAVE, and return the name of the slave end in NAME. */ +int +openpty (int *amaster, int *aslave, char *name, + const struct termios *termp, const struct winsize *winp) +{ +#ifdef PATH_MAX + char _buf[PATH_MAX]; +#else + char _buf[512]; +#endif + char *buf = _buf; + int master, slave; + + master = getpt (); + if (master == -1) + return -1; + + if (grantpt (master)) + goto fail; + + if (unlockpt (master)) + goto fail; + + if (pts_name (master, &buf, sizeof (_buf))) + goto fail; + + slave = open (buf, O_RDWR | O_NOCTTY); + if (slave == -1) + { + if (buf != _buf) + free (buf); + + goto fail; + } + + /* XXX Should we ignore errors here? */ + if (termp) + tcsetattr (slave, TCSAFLUSH, termp); +#ifdef TIOCSWINSZ + if (winp) + ioctl (slave, TIOCSWINSZ, winp); +#endif + + *amaster = master; + *aslave = slave; + if (name != NULL) + strcpy (name, buf); + + if (buf != _buf) + free (buf); + return 0; + + fail: + close (master); + return -1; +} +libutil_hidden_def (openpty) |