| fmtcheck.3 (108087) | fmtcheck.3 (131504) |
|---|---|
| 1.\" Copyright (c) 2000 The NetBSD Foundation, Inc. 2.\" All rights reserved. 3.\" 4.\" This file was contributed to The NetBSD Foundation by Allen Briggs. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: --- 17 unchanged lines hidden (view full) --- 26.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 27.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 28.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 29.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 30.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 31.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 32.\" POSSIBILITY OF SUCH DAMAGE. 33.\" | 1.\" Copyright (c) 2000 The NetBSD Foundation, Inc. 2.\" All rights reserved. 3.\" 4.\" This file was contributed to The NetBSD Foundation by Allen Briggs. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: --- 17 unchanged lines hidden (view full) --- 26.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 27.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 28.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 29.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 30.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 31.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 32.\" POSSIBILITY OF SUCH DAMAGE. 33.\" |
| 34.\" $FreeBSD: head/lib/libc/gen/fmtcheck.3 108087 2002-12-19 09:40:28Z ru $ | 34.\" $FreeBSD: head/lib/libc/gen/fmtcheck.3 131504 2004-07-02 23:52:20Z ru $ |
| 35.Dd October 16, 2002 36.Os 37.Dt FMTCHECK 3 38.Sh NAME 39.Nm fmtcheck 40.Nd sanitizes user-supplied 41.Xr printf 3 Ns -style 42format string --- 16 unchanged lines hidden (view full) --- 59.Fa fmt_default 60and to ensure that 61.Fa fmt_suspect 62is a valid format string. 63.Pp 64The 65.Xr printf 3 66family of functions cannot verify the types of arguments that they are | 35.Dd October 16, 2002 36.Os 37.Dt FMTCHECK 3 38.Sh NAME 39.Nm fmtcheck 40.Nd sanitizes user-supplied 41.Xr printf 3 Ns -style 42format string --- 16 unchanged lines hidden (view full) --- 59.Fa fmt_default 60and to ensure that 61.Fa fmt_suspect 62is a valid format string. 63.Pp 64The 65.Xr printf 3 66family of functions cannot verify the types of arguments that they are |
| 67passed at run-time. In some cases, like | 67passed at run-time. 68In some cases, like |
| 68.Xr catgets 3 , 69it is useful or necessary to use a user-supplied format string with no 70guarantee that the format string matches the specified arguments. 71.Pp 72The 73.Fn fmtcheck 74was designed to be used in these cases, as in: 75.Bd -literal -offset indent 76printf(fmtcheck(user_format, standard_format), arg1, arg2); 77.Ed 78.Pp | 69.Xr catgets 3 , 70it is useful or necessary to use a user-supplied format string with no 71guarantee that the format string matches the specified arguments. 72.Pp 73The 74.Fn fmtcheck 75was designed to be used in these cases, as in: 76.Bd -literal -offset indent 77printf(fmtcheck(user_format, standard_format), arg1, arg2); 78.Ed 79.Pp |
| 79In the check, field widths, fillers, precisions, etc. are ignored (unless | 80In the check, field widths, fillers, precisions, etc.\& are ignored (unless |
| 80the field width or precision is an asterisk 81.Ql * | 81the field width or precision is an asterisk 82.Ql * |
| 82instead of a digit string). Also, any text other than the format specifiers | 83instead of a digit string). 84Also, any text other than the format specifiers |
| 83is completely ignored. 84.Sh RETURN VALUES 85If 86.Fa fmt_suspect 87is a valid format and consumes the same argument types as 88.Fa fmt_default , 89then the 90.Fn fmtcheck 91will return 92.Fa fmt_suspect . 93Otherwise, it will return 94.Fa fmt_default . 95.Sh SECURITY CONSIDERATIONS 96Note that the formats may be quite different as long as they accept the | 85is completely ignored. 86.Sh RETURN VALUES 87If 88.Fa fmt_suspect 89is a valid format and consumes the same argument types as 90.Fa fmt_default , 91then the 92.Fn fmtcheck 93will return 94.Fa fmt_suspect . 95Otherwise, it will return 96.Fa fmt_default . 97.Sh SECURITY CONSIDERATIONS 98Note that the formats may be quite different as long as they accept the |
| 97same arguments. For example, | 99same arguments. 100For example, |
| 98.Qq Li "%p %o %30s %#llx %-10.*e %n" 99is compatible with 100.Qq Li "This number %lu %d%% and string %s has %qd numbers and %.*g floats (%n)" . 101However, 102.Qq Li %o 103is not equivalent to 104.Qq Li %lx 105because 106the first requires an integer and the second requires a long. 107.Sh SEE ALSO 108.Xr printf 3 109.Sh BUGS 110The 111.Fn fmtcheck 112function does not understand all of the conversions that 113.Xr printf 3 114does. | 101.Qq Li "%p %o %30s %#llx %-10.*e %n" 102is compatible with 103.Qq Li "This number %lu %d%% and string %s has %qd numbers and %.*g floats (%n)" . 104However, 105.Qq Li %o 106is not equivalent to 107.Qq Li %lx 108because 109the first requires an integer and the second requires a long. 110.Sh SEE ALSO 111.Xr printf 3 112.Sh BUGS 113The 114.Fn fmtcheck 115function does not understand all of the conversions that 116.Xr printf 3 117does. |