SSL_alloc_buffers.3ossl 6.3 KB

123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197
  1. .\" Automatically generated by Pod::Man 4.14 (Pod::Simple 3.42)
  2. .\"
  3. .\" Standard preamble:
  4. .\" ========================================================================
  5. .de Sp \" Vertical space (when we can't use .PP)
  6. .if t .sp .5v
  7. .if n .sp
  8. ..
  9. .de Vb \" Begin verbatim text
  10. .ft CW
  11. .nf
  12. .ne \\$1
  13. ..
  14. .de Ve \" End verbatim text
  15. .ft R
  16. .fi
  17. ..
  18. .\" Set up some character translations and predefined strings. \*(-- will
  19. .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left
  20. .\" double quote, and \*(R" will give a right double quote. \*(C+ will
  21. .\" give a nicer C++. Capital omega is used to do unbreakable dashes and
  22. .\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff,
  23. .\" nothing in troff, for use with C<>.
  24. .tr \(*W-
  25. .ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p'
  26. .ie n \{\
  27. . ds -- \(*W-
  28. . ds PI pi
  29. . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch
  30. . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch
  31. . ds L" ""
  32. . ds R" ""
  33. . ds C` ""
  34. . ds C' ""
  35. 'br\}
  36. .el\{\
  37. . ds -- \|\(em\|
  38. . ds PI \(*p
  39. . ds L" ``
  40. . ds R" ''
  41. . ds C`
  42. . ds C'
  43. 'br\}
  44. .\"
  45. .\" Escape single quotes in literal strings from groff's Unicode transform.
  46. .ie \n(.g .ds Aq \(aq
  47. .el .ds Aq '
  48. .\"
  49. .\" If the F register is >0, we'll generate index entries on stderr for
  50. .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
  51. .\" entries marked with X<> in POD. Of course, you'll have to process the
  52. .\" output yourself in some meaningful fashion.
  53. .\"
  54. .\" Avoid warning from groff about undefined register 'F'.
  55. .de IX
  56. ..
  57. .nr rF 0
  58. .if \n(.g .if rF .nr rF 1
  59. .if (\n(rF:(\n(.g==0)) \{\
  60. . if \nF \{\
  61. . de IX
  62. . tm Index:\\$1\t\\n%\t"\\$2"
  63. ..
  64. . if !\nF==2 \{\
  65. . nr % 0
  66. . nr F 2
  67. . \}
  68. . \}
  69. .\}
  70. .rr rF
  71. .\"
  72. .\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
  73. .\" Fear. Run. Save yourself. No user-serviceable parts.
  74. . \" fudge factors for nroff and troff
  75. .if n \{\
  76. . ds #H 0
  77. . ds #V .8m
  78. . ds #F .3m
  79. . ds #[ \f1
  80. . ds #] \fP
  81. .\}
  82. .if t \{\
  83. . ds #H ((1u-(\\\\n(.fu%2u))*.13m)
  84. . ds #V .6m
  85. . ds #F 0
  86. . ds #[ \&
  87. . ds #] \&
  88. .\}
  89. . \" simple accents for nroff and troff
  90. .if n \{\
  91. . ds ' \&
  92. . ds ` \&
  93. . ds ^ \&
  94. . ds , \&
  95. . ds ~ ~
  96. . ds /
  97. .\}
  98. .if t \{\
  99. . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u"
  100. . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u'
  101. . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u'
  102. . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u'
  103. . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u'
  104. . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u'
  105. .\}
  106. . \" troff and (daisy-wheel) nroff accents
  107. .ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V'
  108. .ds 8 \h'\*(#H'\(*b\h'-\*(#H'
  109. .ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#]
  110. .ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H'
  111. .ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u'
  112. .ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#]
  113. .ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#]
  114. .ds ae a\h'-(\w'a'u*4/10)'e
  115. .ds Ae A\h'-(\w'A'u*4/10)'E
  116. . \" corrections for vroff
  117. .if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u'
  118. .if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u'
  119. . \" for low resolution devices (crt and lpr)
  120. .if \n(.H>23 .if \n(.V>19 \
  121. \{\
  122. . ds : e
  123. . ds 8 ss
  124. . ds o a
  125. . ds d- d\h'-1'\(ga
  126. . ds D- D\h'-1'\(hy
  127. . ds th \o'bp'
  128. . ds Th \o'LP'
  129. . ds ae ae
  130. . ds Ae AE
  131. .\}
  132. .rm #[ #] #H #V #F C
  133. .\" ========================================================================
  134. .\"
  135. .IX Title "SSL_ALLOC_BUFFERS 3ossl"
  136. .TH SSL_ALLOC_BUFFERS 3ossl "2024-09-03" "3.3.2" "OpenSSL"
  137. .\" For nroff, turn off justification. Always turn off hyphenation; it makes
  138. .\" way too many mistakes in technical documents.
  139. .if n .ad l
  140. .nh
  141. .SH "NAME"
  142. SSL_free_buffers, SSL_alloc_buffers \- manage SSL structure buffers
  143. .SH "SYNOPSIS"
  144. .IX Header "SYNOPSIS"
  145. .Vb 1
  146. \& #include <openssl/ssl.h>
  147. \&
  148. \& int SSL_free_buffers(SSL *ssl);
  149. \& int SSL_alloc_buffers(SSL *ssl);
  150. .Ve
  151. .SH "DESCRIPTION"
  152. .IX Header "DESCRIPTION"
  153. \&\fBSSL_free_buffers()\fR frees the read and write buffers of the given \fBssl\fR.
  154. \&\fBSSL_alloc_buffers()\fR allocates the read and write buffers of the given \fBssl\fR.
  155. .PP
  156. The \fB\s-1SSL_MODE_RELEASE_BUFFERS\s0\fR mode releases read or write buffers whenever
  157. the buffers have been drained. These functions allow applications to manually
  158. control when buffers are freed and allocated.
  159. .PP
  160. After freeing the buffers, the buffers are automatically reallocated upon a
  161. new read or write. The \fBSSL_alloc_buffers()\fR does not need to be called, but
  162. can be used to make sure the buffers are preallocated. This can be used to
  163. avoid allocation during data processing or with \fBCRYPTO_set_mem_functions()\fR
  164. to control where and how buffers are allocated.
  165. .PP
  166. These functions are no-ops when used with \s-1QUIC SSL\s0 objects. For \s-1QUIC,\s0
  167. \&\fBSSL_free_buffers()\fR always fails, and \fBSSL_alloc_buffers()\fR always succeeds.
  168. .SH "RETURN VALUES"
  169. .IX Header "RETURN VALUES"
  170. The following return values can occur:
  171. .IP "0 (Failure)" 4
  172. .IX Item "0 (Failure)"
  173. The \fBSSL_free_buffers()\fR function returns 0 when there is pending data to be
  174. read or written. The \fBSSL_alloc_buffers()\fR function returns 0 when there is
  175. an allocation failure.
  176. .IP "1 (Success)" 4
  177. .IX Item "1 (Success)"
  178. The \fBSSL_free_buffers()\fR function returns 1 if the buffers have been freed. This
  179. value is also returned if the buffers had been freed before calling
  180. \&\fBSSL_free_buffers()\fR.
  181. The \fBSSL_alloc_buffers()\fR function returns 1 if the buffers have been allocated.
  182. This value is also returned if the buffers had been allocated before calling
  183. \&\fBSSL_alloc_buffers()\fR.
  184. .SH "SEE ALSO"
  185. .IX Header "SEE ALSO"
  186. \&\fBssl\fR\|(7),
  187. \&\fBSSL_free\fR\|(3), \fBSSL_clear\fR\|(3),
  188. \&\fBSSL_new\fR\|(3), \fBSSL_CTX_set_mode\fR\|(3),
  189. \&\fBCRYPTO_set_mem_functions\fR\|(3)
  190. .SH "COPYRIGHT"
  191. .IX Header "COPYRIGHT"
  192. Copyright 2017\-2023 The OpenSSL Project Authors. All Rights Reserved.
  193. .PP
  194. Licensed under the Apache License 2.0 (the \*(L"License\*(R"). You may not use
  195. this file except in compliance with the License. You can obtain a copy
  196. in the file \s-1LICENSE\s0 in the source distribution or at
  197. <https://www.openssl.org/source/license.html>.