Edit File: buffer.3
.\" Automatically generated by Pod::Man 4.11 (Pod::Simple 3.35) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" Set up some character translations and predefined strings. \*(-- will .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left .\" double quote, and \*(R" will give a right double quote. \*(C+ will .\" give a nicer C++. Capital omega is used to do unbreakable dashes and .\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff, .\" nothing in troff, for use with C<>. .tr \(*W- .ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p' .ie n \{\ . ds -- \(*W- . ds PI pi . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch . ds L" "" . ds R" "" . ds C` "" . ds C' "" 'br\} .el\{\ . ds -- \|\(em\| . ds PI \(*p . ds L" `` . ds R" '' . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is >0, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{\ . if \nF \{\ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{\ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" .\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2). .\" Fear. Run. Save yourself. No user-serviceable parts. . \" fudge factors for nroff and troff .if n \{\ . ds #H 0 . ds #V .8m . ds #F .3m . ds #[ \f1 . ds #] \fP .\} .if t \{\ . ds #H ((1u-(\\\\n(.fu%2u))*.13m) . ds #V .6m . ds #F 0 . ds #[ \& . ds #] \& .\} . \" simple accents for nroff and troff .if n \{\ . ds ' \& . ds ` \& . ds ^ \& . ds , \& . ds ~ ~ . ds / .\} .if t \{\ . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u" . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u' . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u' . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u' . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u' . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u' .\} . \" troff and (daisy-wheel) nroff accents .ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V' .ds 8 \h'\*(#H'\(*b\h'-\*(#H' .ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#] .ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H' .ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u' .ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#] .ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#] .ds ae a\h'-(\w'a'u*4/10)'e .ds Ae A\h'-(\w'A'u*4/10)'E . \" corrections for vroff .if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u' .if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u' . \" for low resolution devices (crt and lpr) .if \n(.H>23 .if \n(.V>19 \ \{\ . ds : e . ds 8 ss . ds o a . ds d- d\h'-1'\(ga . ds D- D\h'-1'\(hy . ds th \o'bp' . ds Th \o'LP' . ds ae ae . ds Ae AE .\} .rm #[ #] #H #V #F C .\" ======================================================================== .\" .IX Title "buffer 3" .TH buffer 3 "2019-12-20" "1.0.2u" "OpenSSL" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH "NAME" BUF_MEM_new, BUF_MEM_new_ex, BUF_MEM_free, BUF_MEM_grow \- simple character array structure .PP BUF_strdup, BUF_strndup, BUF_memdup, BUF_strlcpy, BUF_strlcat \- standard C library equivalents .SH "SYNOPSIS" .IX Header "SYNOPSIS" .Vb 1 \& #include <openssl/buffer.h> \& \& BUF_MEM *BUF_MEM_new(void); \& \& void BUF_MEM_free(BUF_MEM *a); \& \& int BUF_MEM_grow(BUF_MEM *str, int len); \& \& char *BUF_strdup(const char *str); \& \& char *BUF_strndup(const char *str, size_t siz); \& \& void *BUF_memdup(const void *data, size_t siz); \& \& size_t BUF_strlcpy(char *dst, const char *src, size_t size); \& \& size_t BUF_strlcat(char *dst, const char *src, size_t size); \& \& size_t BUF_strnlen(const char *str, size_t maxlen); .Ve .SH "DESCRIPTION" .IX Header "DESCRIPTION" The buffer library handles simple character arrays. Buffers are used for various purposes in the library, most notably memory BIOs. .PP \&\fBBUF_MEM_new()\fR allocates a new buffer of zero size. .PP \&\fBBUF_MEM_free()\fR frees up an already existing buffer. The data is zeroed before freeing up in case the buffer contains sensitive data. .PP \&\fBBUF_MEM_grow()\fR changes the size of an already existing buffer to \&\fBlen\fR. Any data already in the buffer is preserved if it increases in size. .PP \&\fBBUF_strdup()\fR, \fBBUF_strndup()\fR, \fBBUF_memdup()\fR, \fBBUF_strlcpy()\fR, \&\fBBUF_strlcat()\fR and BUF_strnlen are equivalents of the standard C library functions. The \fBdup()\fR functions use \fBOPENSSL_malloc()\fR underneath and so should be used in preference to the standard library for memory leak checking or replacing the \fBmalloc()\fR function. .PP Memory allocated from these functions should be freed up using the \&\fBOPENSSL_free()\fR function. .PP BUF_strndup makes the explicit guarantee that it will never read past the first \fBsiz\fR bytes of \fBstr\fR. .SH "RETURN VALUES" .IX Header "RETURN VALUES" \&\fBBUF_MEM_new()\fR returns the buffer or \s-1NULL\s0 on error. .PP \&\fBBUF_MEM_free()\fR has no return value. .PP \&\fBBUF_MEM_grow()\fR returns zero on error or the new size (i.e. \fBlen\fR). .SH "SEE ALSO" .IX Header "SEE ALSO" \&\fBbio\fR\|(3) .SH "HISTORY" .IX Header "HISTORY" \&\fBBUF_MEM_new()\fR, \fBBUF_MEM_free()\fR and \fBBUF_MEM_grow()\fR are available in all versions of SSLeay and OpenSSL. \fBBUF_strdup()\fR was added in SSLeay 0.8.