1.\" 2.\" Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com> 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 3. The name of the author may not be used to endorse or promote products 14.\" derived from this software without specific prior written permission. 15.\" 16.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 17.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 18.\" AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 19.\" THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 20.\" EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 21.\" PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 22.\" OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 23.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 24.\" OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 25.\" ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26.\" 27.\" $OpenBSD: a64l.3,v 1.3 1999/02/27 21:55:53 deraadt Exp $ 28.\" 29.Dd August 17, 1997 30.Dt A64L 3 31.Os 32.Sh NAME 33.Nm a64l , 34.Nm l64a 35.Nd convert between 32-bit integer and radix-64 ASCII string 36.Sh SYNOPSIS 37.Fd #include <stdlib.h> 38.Ft long 39.Fn a64l "const char *s" 40.Ft char * 41.Fn l64a "long l" 42.Sh DESCRIPTION 43The 44.Fn a64l 45and 46.Fn l64a 47functions are used to maintain numbers stored in radix-64 48ASCII characters. This is a notation by which 32-bit integers 49can be represented by up to six characters; each character 50represents a "digit" in a radix-64 notation. 51.Pp 52The characters used to represent "digits" are '.' for 0, '/' for 1, 53'0' through '9' for 2-11, 'A' through 'Z' for 12-37, and 'a' through 54'z' for 38-63. 55.Pp 56The 57.Fn a64l 58function takes a pointer to a null-terminated radix-64 representation 59and returns a corresponding 32-bit value. If the string pointed to by 60.Ar s 61contains more than six characters, 62.Fn a64l 63will use the first six. 64.Fn a64l 65scans the character string from left to right, decoding 66each character as a 6-bit radix-64 number. If a long integer is 67larger than 32 bits, the return value will be sign-extended. 68.Pp 69.Fn l64a 70takes a long integer argument 71.Ar l 72and returns a pointer to the corresponding radix-64 representation. 73.Sh RETURN VALUES 74On success, 75.Fn a64l 76returns a 32-bit representation of 77.Ar s . 78If 79.Ar s 80is a NULL pointer or if it contains "digits" other than those described above, 81.Fn a64l 82returns -1L and sets the global variable errno to 83.Va EINVAL . 84.Pp 85On success, 86.Fn l64a 87returns a pointer to a string containing the radix-64 representation of 88.Ar l . 89If 90.Ar l 91is 0, 92.Fn l64a 93returns a pointer to the empty string. 94If 95.Ar l 96is negative, 97.Fn l64a 98returns a NULL pointer and sets the global variable errno to 99.Va EINVAL . 100.Sh WARNINGS 101The value returned by 102.Fn l64a 103is a pointer into a static buffer, the contents of which 104will be overwritten by subsequent calls. 105.Pp 106The value returned by 107.Fn a64l 108may be incorrect if the value is too large; for that reason, only strings 109that resulted from a call to 110.Fn l64a 111should be used to call 112.Fn a64l . 113.Pp 114If a long integer is larger than 32 bits, only the low-order 11532 bits are used. 116.Sh STANDARDS 117The 118.Fn a64l 119and 120.Fn l64a 121functions conform to 122.St -xpg4.2 . 123