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Diffstat (limited to 'string/strlcpy.3')
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diff --git a/string/strlcpy.3 b/string/strlcpy.3 deleted file mode 100644 index 8b07d0c4..00000000 --- a/string/strlcpy.3 +++ /dev/null @@ -1,202 +0,0 @@ -.\" $NetBSD: strlcpy.3,v 1.11 2003/06/26 12:25:22 wiz Exp $ -.\" from OpenBSD: strlcpy.3,v 1.11 2000/11/16 23:27:41 angelos Exp -.\" -.\" Copyright (c) 1998, 2000 Todd C. Miller <Todd.Miller@courtesan.com> -.\" All rights reserved. -.\" -.\" Redistribution and use in source and binary forms, with or without -.\" modification, are permitted provided that the following conditions -.\" are met: -.\" 1. Redistributions of source code must retain the above copyright -.\" notice, this list of conditions and the following disclaimer. -.\" 2. Redistributions in binary form must reproduce the above copyright -.\" notice, this list of conditions and the following disclaimer in the -.\" documentation and/or other materials provided with the distribution. -.\" 3. The name of the author may not be used to endorse or promote products -.\" derived from this software without specific prior written permission. -.\" -.\" THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, -.\" INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY -.\" AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL -.\" THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, -.\" EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, -.\" PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; -.\" OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, -.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR -.\" OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF -.\" ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -.\" -.Dd March 1, 2001 -.Dt STRLCPY 3 -.Os -.Sh NAME -.Nm strlcpy , -.Nm strlcat -.Nd size-bounded string copying and concatenation -.Sh LIBRARY -.Lb libc -.Sh SYNOPSIS -.In string.h -.Ft size_t -.Fn strlcpy "char *dst" "const char *src" "size_t size" -.Ft size_t -.Fn strlcat "char *dst" "const char *src" "size_t size" -.Sh DESCRIPTION -The -.Fn strlcpy -and -.Fn strlcat -functions copy and concatenate strings respectively. -They are designed -to be safer, more consistent, and less error prone replacements for -.Xr strncpy 3 -and -.Xr strncat 3 . -Unlike those functions, -.Fn strlcpy -and -.Fn strlcat -take the full size of the buffer (not just the length) and guarantee to -NUL-terminate the result (as long as -.Fa size -is larger than 0 or, in the case of -.Fn strlcat , -as long as there is at least one byte free in -.Fa dst ) . -Note that you should include a byte for the NUL in -.Fa size . -Also note that -.Fn strlcpy -and -.Fn strlcat -only operate on true -.Dq C -strings. -This means that for -.Fn strlcpy -.Fa src -must be NUL-terminated and for -.Fn strlcat -both -.Fa src -and -.Fa dst -must be NUL-terminated. -.Pp -The -.Fn strlcpy -function copies up to -.Fa size -- 1 characters from the NUL-terminated string -.Fa src -to -.Fa dst , -NUL-terminating the result. -.Pp -The -.Fn strlcat -function appends the NUL-terminated string -.Fa src -to the end of -.Fa dst . -It will append at most -.Fa size -- strlen(dst) - 1 bytes, NUL-terminating the result. -.Sh RETURN VALUES -The -.Fn strlcpy -and -.Fn strlcat -functions return the total length of the string they tried to create. -For -.Fn strlcpy -that means the length of -.Fa src . -For -.Fn strlcat -that means the initial length of -.Fa dst -plus -the length of -.Fa src . -While this may seem somewhat confusing it was done to make -truncation detection simple. -.Pp -Note however, that if -.Fn strlcat -traverses -.Fa size -characters without finding a NUL, the length of the string is considered -to be -.Fa size -and the destination string will not be NUL-terminated (since there was -no space for the NUL). -This keeps -.Fn strlcat -from running off the end of a string. -In practice this should not happen (as it means that either -.Fa size -is incorrect or that -.Fa dst -is not a proper -.Dq C -string). -The check exists to prevent potential security problems in incorrect code. -.Sh EXAMPLES -The following code fragment illustrates the simple case: -.Bd -literal -offset indent -char *s, *p, buf[BUFSIZ]; - -\&... - -(void)strlcpy(buf, s, sizeof(buf)); -(void)strlcat(buf, p, sizeof(buf)); -.Ed -.Pp -To detect truncation, perhaps while building a pathname, something -like the following might be used: -.Bd -literal -offset indent -char *dir, *file, pname[MAXPATHLEN]; - -\&... - -if (strlcpy(pname, dir, sizeof(pname)) \*[Ge] sizeof(pname)) - goto toolong; -if (strlcat(pname, file, sizeof(pname)) \*[Ge] sizeof(pname)) - goto toolong; -.Ed -.Pp -Since we know how many characters we copied the first time, we can -speed things up a bit by using a copy instead of an append: -.Bd -literal -offset indent -char *dir, *file, pname[MAXPATHLEN]; -size_t n; - -\&... - -n = strlcpy(pname, dir, sizeof(pname)); -if (n \*[Ge] sizeof(pname)) - goto toolong; -if (strlcpy(pname + n, file, sizeof(pname) - n) \*[Ge] sizeof(pname) - n) - goto toolong; -.Ed -.Pp -However, one may question the validity of such optimizations, as they -defeat the whole purpose of -.Fn strlcpy -and -.Fn strlcat . -.Sh SEE ALSO -.Xr snprintf 3 , -.Xr strncat 3 , -.Xr strncpy 3 -.Sh HISTORY -.Fn strlcpy -and -.Fn strlcat -first appeared in -.Ox 2.4 , -then in -.Nx 1.4.3 -and -.Fx 3.3 . |