1.\" Copyright (c) 1997 Todd C. Miller <Todd.Miller@courtesan.com> 2.\" All rights reserved. 3.\" 4.\" Redistribution and use in source and binary forms, with or without 5.\" modification, are permitted provided that the following conditions 6.\" are met: 7.\" 1. Redistributions of source code must retain the above copyright 8.\" notice, this list of conditions and the following disclaimer. 9.\" 2. Redistributions in binary form must reproduce the above copyright 10.\" notice, this list of conditions and the following disclaimer in the 11.\" documentation and/or other materials provided with the distribution. 12.\" 3. The name of the author may not be used to endorse or promote products 13.\" derived from this software without specific prior written permission. 14.\" 15.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, 16.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 17.\" AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL 18.\" THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 19.\" EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 20.\" PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 21.\" OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 22.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 23.\" OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 24.\" ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25.\" 26.\" $OpenBSD: a64l.3,v 1.5 2000/04/20 13:50:01 aaron Exp $ 27.\" 28.Dd August 17, 1997 29.Dt A64L 3 30.Os 31.Sh NAME 32.Nm a64l , 33.Nm l64a 34.Nd convert between 32-bit integer and radix-64 ASCII string 35.Sh SYNOPSIS 36.Fd #include <stdlib.h> 37.Ft long 38.Fn a64l "const char *s" 39.Ft char * 40.Fn l64a "long l" 41.Sh DESCRIPTION 42The 43.Fn a64l 44and 45.Fn l64a 46functions are used to maintain numbers stored in radix-64 47.Tn ASCII 48characters. 49This is a notation by which 32-bit integers 50can be represented by up to six characters; each character represents a 51.Dq digit 52in a radix-64 notation. 53.Pp 54The characters used to represent digits are 55.Ql \&. 56for 0, 57.Ql / 58for 1, 59.Ql 0 60through 61.Ql 9 62for 2-11, 63.Ql A 64through 65.Ql Z 66for 12-37, and 67.Ql a 68through 69.Ql z 70for 38-63. 71.Pp 72The 73.Fn a64l 74function takes a pointer to a null-terminated radix-64 representation 75and returns a corresponding 32-bit value. 76If the string pointed to by 77.Fa s 78contains more than six characters, 79.Fn a64l 80will use the first six. 81.Fn a64l 82scans the character string from left to right, decoding 83each character as a 6-bit radix-64 number. 84If a long integer is 85larger than 32 bits, the return value will be sign-extended. 86.Pp 87.Fn l64a 88takes a long integer argument 89.Fa l 90and returns a pointer to the corresponding radix-64 representation. 91.Sh RETURN VALUES 92On success, 93.Fn a64l 94returns a 32-bit representation of 95.Fa s . 96If 97.Fa s 98is a null pointer or if it contains digits other than those described above. 99.Fn a64l 100returns \-1 and sets the global variable 101.Va errno 102to 103.Er EINVAL . 104.Pp 105On success, 106.Fn l64a 107returns a pointer to a string containing the radix-64 representation of 108.Fa l . 109If 110.Fa l 111is 0, 112.Fn l64a 113returns a pointer to the empty string. 114If 115.Fa l 116is negative, 117.Fn l64a 118returns a null pointer and sets the global variable 119.Va errno 120to 121.Er EINVAL . 122.Sh WARNINGS 123The value returned by 124.Fn l64a 125is a pointer into a static buffer, the contents of which 126will be overwritten by subsequent calls. 127.Pp 128The value returned by 129.Fn a64l 130may be incorrect if the value is too large; for that reason, only strings 131that resulted from a call to 132.Fn l64a 133should be used to call 134.Fn a64l . 135.Pp 136If a long integer is larger than 32 bits, only the low-order 13732 bits are used. 138.Sh STANDARDS 139The 140.Fn a64l 141and 142.Fn l64a 143functions conform to 144.St -xpg4.2 . 145