diff options
Diffstat (limited to 'REORG.TODO/login/login.c')
| -rw-r--r-- | REORG.TODO/login/login.c | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/REORG.TODO/login/login.c b/REORG.TODO/login/login.c new file mode 100644 index 0000000000..b8171de83c --- /dev/null +++ b/REORG.TODO/login/login.c @@ -0,0 +1,143 @@ +/* Copyright (C) 1996-2017 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996. + + 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 <assert.h> +#include <errno.h> +#include <limits.h> +#include <string.h> +#include <unistd.h> +#include <stdlib.h> +#include <utmp.h> + + +/* Return the result of ttyname in the buffer pointed to by TTY, 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 TTY. + 0 is returned upon success, -1 otherwise. */ +static int +tty_name (int fd, char **tty, size_t buf_len) +{ + int rv; /* Return value. 0 = success. */ + char *buf = *tty; /* Buffer for ttyname, initially the user's. */ + + for (;;) + { + char *new_buf; + + if (buf_len) + { + rv = ttyname_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 != *tty) + /* 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) + *tty = buf; /* Return buffer to the user. */ + else if (buf != *tty) + free (buf); /* Free what we malloced when returning an error. */ + + return rv; +} + +void +login (const struct utmp *ut) +{ +#ifdef PATH_MAX + char _tty[PATH_MAX + UT_LINESIZE]; +#else + char _tty[512 + UT_LINESIZE]; +#endif + char *tty = _tty; + int found_tty; + const char *ttyp; + struct utmp copy = *ut; + + /* Fill in those fields we supply. */ +#if _HAVE_UT_TYPE - 0 + copy.ut_type = USER_PROCESS; +#endif +#if _HAVE_UT_PID - 0 + copy.ut_pid = getpid (); +#endif + + /* Seek tty. */ + found_tty = tty_name (STDIN_FILENO, &tty, sizeof (_tty)); + if (found_tty < 0) + found_tty = tty_name (STDOUT_FILENO, &tty, sizeof (_tty)); + if (found_tty < 0) + found_tty = tty_name (STDERR_FILENO, &tty, sizeof (_tty)); + + if (found_tty >= 0) + { + /* We only want to insert the name of the tty without path. + But take care of name like /dev/pts/3. */ + if (strncmp (tty, "/dev/", 5) == 0) + ttyp = tty + 5; /* Skip the "/dev/". */ + else + ttyp = basename (tty); + + /* Position to record for this tty. */ + strncpy (copy.ut_line, ttyp, UT_LINESIZE); + + /* Tell that we want to use the UTMP file. */ + if (utmpname (_PATH_UTMP) == 0) + { + /* Open UTMP file. */ + setutent (); + + /* Write the entry. */ + pututline (©); + + /* Close UTMP file. */ + endutent (); + } + + if (tty != _tty) + free (tty); /* Free buffer malloced by tty_name. */ + } + else + /* We provide a default value so that the output does not contain + an random bytes in this field. */ + strncpy (copy.ut_line, "???", UT_LINESIZE); + + /* Update the WTMP file. Here we have to add a new entry. */ + updwtmp (_PATH_WTMP, ©); +} |