1.\"- 2.\" Copyright (c) 2001-2003 Networks Associates Technology, Inc. 3.\" Copyright (c) 2004-2011 Dag-Erling Smørgrav 4.\" All rights reserved. 5.\" 6.\" This software was developed for the FreeBSD Project by ThinkSec AS and 7.\" Network Associates Laboratories, the Security Research Division of 8.\" Network Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 9.\" ("CBOSS"), as part of the DARPA CHATS research program. 10.\" 11.\" Redistribution and use in source and binary forms, with or without 12.\" modification, are permitted provided that the following conditions 13.\" are met: 14.\" 1. Redistributions of source code must retain the above copyright 15.\" notice, this list of conditions and the following disclaimer. 16.\" 2. Redistributions in binary form must reproduce the above copyright 17.\" notice, this list of conditions and the following disclaimer in the 18.\" documentation and/or other materials provided with the distribution. 19.\" 3. The name of the author may not be used to endorse or promote 20.\" products derived from this software without specific prior written 21.\" permission. 22.\" 23.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 24.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 25.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 26.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 27.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 28.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 29.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 30.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 32.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 33.\" SUCH DAMAGE. 34.\" 35.\" $Id$ 36.\" 37.Dd March 3, 2013 38.Dt OPENPAM_STRADDCH 3 39.Os 40.Sh NAME 41.Nm openpam_straddch 42.Nd add a character to a string, expanding the buffer if needed 43.Sh LIBRARY 44.Lb libpam 45.Sh SYNOPSIS 46.In sys/types.h 47.In security/pam_appl.h 48.In security/openpam.h 49.Ft "int" 50.Fn openpam_straddch "char **str" "size_t *size" "size_t *len" "int ch" 51.Sh DESCRIPTION 52The 53.Fn openpam_straddch 54function appends a character to a dynamically 55allocated NUL-terminated buffer, reallocating the buffer as needed. 56.Pp 57The 58.Fa str 59argument points to a variable containing either a pointer to 60an existing buffer or 61.Dv NULL . 62If the value of the variable pointed to by 63.Fa str 64is 65.Dv NULL , 66a new buffer 67is allocated. 68.Pp 69The 70.Fa size 71and 72.Fa len 73argument point to variables used to hold the size 74of the buffer and the length of the string it contains, respectively. 75.Pp 76The final argument, 77.Fa ch , 78is the character that should be appended to 79the string. If 80.Fa ch 81is 0, nothing is appended, but a new buffer is 82still allocated if 83.Fa str 84is NULL. This can be used to 85.Do 86bootstrap 87.Dc 88the 89string. 90.Pp 91If a new buffer is allocated or an existing buffer is reallocated to 92make room for the additional character, 93.Fa str 94and 95.Fa size 96are updated 97accordingly. 98.Pp 99The 100.Fn openpam_straddch 101function ensures that the buffer is always 102NUL-terminated. 103.Pp 104If the 105.Fn openpam_straddch 106function is successful, it increments the 107integer variable pointed to by 108.Fa len 109(unless 110.Fa ch 111was 0) and returns 0. 112Otherwise, it leaves the variables pointed to by 113.Fa str , 114.Fa size 115and 116.Fa len 117unmodified, sets 118.Va errno 119to 120.Dv ENOMEM 121and returns -1. 122.Pp 123.Sh RETURN VALUES 124The 125.Fn openpam_straddch 126function returns 0 on success and -1 on failure. 127.Sh SEE ALSO 128.Xr pam 3 , 129.Xr pam_strerror 3 130.Sh STANDARDS 131The 132.Fn openpam_straddch 133function is an OpenPAM extension. 134.Sh AUTHORS 135The 136.Fn openpam_straddch 137function and this manual page were 138developed by 139.An Dag-Erling Sm\(/orgrav Aq des@des.no . 140