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diff --git a/contrib/bind9/lib/lwres/man/lwres_buffer.html b/contrib/bind9/lib/lwres/man/lwres_buffer.html new file mode 100644 index 0000000..79354fc --- /dev/null +++ b/contrib/bind9/lib/lwres/man/lwres_buffer.html @@ -0,0 +1,576 @@ +<!-- + - Copyright (C) 2004 Internet Systems Consortium, Inc. ("ISC") + - Copyright (C) 2001 Internet Software Consortium. + - + - Permission to use, copy, modify, and distribute this software for any + - purpose with or without fee is hereby granted, provided that the above + - copyright notice and this permission notice appear in all copies. + - + - THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH + - REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY + - AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT, + - INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM + - LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE + - OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR + - PERFORMANCE OF THIS SOFTWARE. +--> + +<!-- $Id: lwres_buffer.html,v 1.4.2.1.4.2 2004/08/22 23:39:03 marka Exp $ --> + +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> +<HTML +><HEAD +><TITLE +>lwres_buffer</TITLE +><META +NAME="GENERATOR" +CONTENT="Modular DocBook HTML Stylesheet Version 1.7"></HEAD +><BODY +CLASS="REFENTRY" +BGCOLOR="#FFFFFF" +TEXT="#000000" +LINK="#0000FF" +VLINK="#840084" +ALINK="#0000FF" +><H1 +><A +NAME="AEN1" +></A +>lwres_buffer</H1 +><DIV +CLASS="REFNAMEDIV" +><A +NAME="AEN8" +></A +><H2 +>Name</H2 +>lwres_buffer_init, lwres_buffer_invalidate, lwres_buffer_add, lwres_buffer_subtract, lwres_buffer_clear, lwres_buffer_first, lwres_buffer_forward, lwres_buffer_back, lwres_buffer_getuint8, lwres_buffer_putuint8, lwres_buffer_getuint16, lwres_buffer_putuint16, lwres_buffer_getuint32, lwres_buffer_putuint32, lwres_buffer_putmem, lwres_buffer_getmem -- lightweight resolver buffer management</DIV +><DIV +CLASS="REFSYNOPSISDIV" +><A +NAME="AEN26" +></A +><H2 +>Synopsis</H2 +><DIV +CLASS="FUNCSYNOPSIS" +><P +></P +><A +NAME="AEN27" +></A +><PRE +CLASS="FUNCSYNOPSISINFO" +>#include <lwres/lwbuffer.h></PRE +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_init</CODE +>(lwres_buffer_t *b, void *base, unsigned int length);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_invalidate</CODE +>(lwres_buffer_t *b);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_add</CODE +>(lwres_buffer_t *b, unsigned int n);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_subtract</CODE +>(lwres_buffer_t *b, unsigned int n);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_clear</CODE +>(lwres_buffer_t *b);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_first</CODE +>(lwres_buffer_t *b);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_forward</CODE +>(lwres_buffer_t *b, unsigned int n);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_back</CODE +>(lwres_buffer_t *b, unsigned int n);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>lwres_uint8_t +lwres_buffer_getuint8</CODE +>(lwres_buffer_t *b);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_putuint8</CODE +>(lwres_buffer_t *b, lwres_uint8_t val);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>lwres_uint16_t +lwres_buffer_getuint16</CODE +>(lwres_buffer_t *b);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_putuint16</CODE +>(lwres_buffer_t *b, lwres_uint16_t val);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>lwres_uint32_t +lwres_buffer_getuint32</CODE +>(lwres_buffer_t *b);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_putuint32</CODE +>(lwres_buffer_t *b, lwres_uint32_t val);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_putmem</CODE +>(lwres_buffer_t *b, const unsigned char *base, unsigned int length);</CODE +></P +><P +><CODE +><CODE +CLASS="FUNCDEF" +>void +lwres_buffer_getmem</CODE +>(lwres_buffer_t *b, unsigned char *base, unsigned int length);</CODE +></P +><P +></P +></DIV +></DIV +><DIV +CLASS="REFSECT1" +><A +NAME="AEN106" +></A +><H2 +>DESCRIPTION</H2 +><P +>These functions provide bounds checked access to a region of memory +where data is being read or written. +They are based on, and similar to, the +<VAR +CLASS="LITERAL" +>isc_buffer_</VAR +> +functions in the ISC library.</P +><P +>A buffer is a region of memory, together with a set of related +subregions. +The <SPAN +CLASS="emphasis" +><I +CLASS="EMPHASIS" +>used region</I +></SPAN +> and the +<SPAN +CLASS="emphasis" +><I +CLASS="EMPHASIS" +>available</I +></SPAN +> region are disjoint, and +their union is the buffer's region. +The used region extends from the beginning of the buffer region to the +last used byte. +The available region extends from one byte greater than the last used +byte to the end of the buffer's region. +The size of the used region can be changed using various +buffer commands. +Initially, the used region is empty.</P +><P +>The used region is further subdivided into two disjoint regions: the +<SPAN +CLASS="emphasis" +><I +CLASS="EMPHASIS" +>consumed region</I +></SPAN +> and the <SPAN +CLASS="emphasis" +><I +CLASS="EMPHASIS" +>remaining region</I +></SPAN +>. +The union of these two regions is the used region. +The consumed region extends from the beginning of the used region to +the byte before the <SPAN +CLASS="emphasis" +><I +CLASS="EMPHASIS" +>current</I +></SPAN +> offset (if any). +The <SPAN +CLASS="emphasis" +><I +CLASS="EMPHASIS" +>remaining</I +></SPAN +> region the current pointer to the end of the used +region. +The size of the consumed region can be changed using various +buffer commands. +Initially, the consumed region is empty.</P +><P +>The <SPAN +CLASS="emphasis" +><I +CLASS="EMPHASIS" +>active region</I +></SPAN +> is an (optional) subregion of the remaining +region. +It extends from the current offset to an offset in the +remaining region. +Initially, the active region is empty. +If the current offset advances beyond the chosen offset, +the active region will also be empty.</P +><P +><PRE +CLASS="PROGRAMLISTING" +> + /------------entire length---------------\\ + /----- used region -----\\/-- available --\\ + +----------------------------------------+ + | consumed | remaining | | + +----------------------------------------+ + a b c d e + + a == base of buffer. + b == current pointer. Can be anywhere between a and d. + c == active pointer. Meaningful between b and d. + d == used pointer. + e == length of buffer. + + a-e == entire length of buffer. + a-d == used region. + a-b == consumed region. + b-d == remaining region. + b-c == optional active region.</PRE +></P +><P +><CODE +CLASS="FUNCTION" +>lwres_buffer_init()</CODE +> +initializes the +<SPAN +CLASS="TYPE" +>lwres_buffer_t</SPAN +> +<VAR +CLASS="PARAMETER" +>*b</VAR +> +and assocates it with the memory region of size +<VAR +CLASS="PARAMETER" +>length</VAR +> +bytes starting at location +<VAR +CLASS="PARAMETER" +>base.</VAR +></P +><P +><CODE +CLASS="FUNCTION" +>lwres_buffer_invalidate()</CODE +> +marks the buffer +<VAR +CLASS="PARAMETER" +>*b</VAR +> +as invalid. Invalidating a buffer after use is not required, +but makes it possible to catch its possible accidental use.</P +><P +>The functions +<CODE +CLASS="FUNCTION" +>lwres_buffer_add()</CODE +> +and +<CODE +CLASS="FUNCTION" +>lwres_buffer_subtract()</CODE +> +respectively increase and decrease the used space in +buffer +<VAR +CLASS="PARAMETER" +>*b</VAR +> +by +<VAR +CLASS="PARAMETER" +>n</VAR +> +bytes. +<CODE +CLASS="FUNCTION" +>lwres_buffer_add()</CODE +> +checks for buffer overflow and +<CODE +CLASS="FUNCTION" +>lwres_buffer_subtract()</CODE +> +checks for underflow. +These functions do not allocate or deallocate memory. +They just change the value of +<CODE +CLASS="STRUCTFIELD" +>used</CODE +>.</P +><P +>A buffer is re-initialised by +<CODE +CLASS="FUNCTION" +>lwres_buffer_clear()</CODE +>. +The function sets +<CODE +CLASS="STRUCTFIELD" +>used</CODE +> , +<CODE +CLASS="STRUCTFIELD" +>current</CODE +> +and +<CODE +CLASS="STRUCTFIELD" +>active</CODE +> +to zero.</P +><P +><CODE +CLASS="FUNCTION" +>lwres_buffer_first</CODE +> +makes the consumed region of buffer +<VAR +CLASS="PARAMETER" +>*p</VAR +> +empty by setting +<CODE +CLASS="STRUCTFIELD" +>current</CODE +> +to zero (the start of the buffer).</P +><P +><CODE +CLASS="FUNCTION" +>lwres_buffer_forward()</CODE +> +increases the consumed region of buffer +<VAR +CLASS="PARAMETER" +>*b</VAR +> +by +<VAR +CLASS="PARAMETER" +>n</VAR +> +bytes, checking for overflow. +Similarly, +<CODE +CLASS="FUNCTION" +>lwres_buffer_back()</CODE +> +decreases buffer +<VAR +CLASS="PARAMETER" +>b</VAR +>'s +consumed region by +<VAR +CLASS="PARAMETER" +>n</VAR +> +bytes and checks for underflow.</P +><P +><CODE +CLASS="FUNCTION" +>lwres_buffer_getuint8()</CODE +> +reads an unsigned 8-bit integer from +<VAR +CLASS="PARAMETER" +>*b</VAR +> +and returns it. +<CODE +CLASS="FUNCTION" +>lwres_buffer_putuint8()</CODE +> +writes the unsigned 8-bit integer +<VAR +CLASS="PARAMETER" +>val</VAR +> +to buffer +<VAR +CLASS="PARAMETER" +>*b</VAR +>.</P +><P +><CODE +CLASS="FUNCTION" +>lwres_buffer_getuint16()</CODE +> +and +<CODE +CLASS="FUNCTION" +>lwres_buffer_getuint32()</CODE +> +are identical to +<CODE +CLASS="FUNCTION" +>lwres_buffer_putuint8()</CODE +> +except that they respectively read an unsigned 16-bit or 32-bit integer +in network byte order from +<VAR +CLASS="PARAMETER" +>b</VAR +>. +Similarly, +<CODE +CLASS="FUNCTION" +>lwres_buffer_putuint16()</CODE +> +and +<CODE +CLASS="FUNCTION" +>lwres_buffer_putuint32()</CODE +> +writes the unsigned 16-bit or 32-bit integer +<VAR +CLASS="PARAMETER" +>val</VAR +> +to buffer +<VAR +CLASS="PARAMETER" +>b</VAR +>, +in network byte order.</P +><P +>Arbitrary amounts of data are read or written from a lightweight +resolver buffer with +<CODE +CLASS="FUNCTION" +>lwres_buffer_getmem()</CODE +> +and +<CODE +CLASS="FUNCTION" +>lwres_buffer_putmem()</CODE +> +respectively. +<CODE +CLASS="FUNCTION" +>lwres_buffer_putmem()</CODE +> +copies +<VAR +CLASS="PARAMETER" +>length</VAR +> +bytes of memory at +<VAR +CLASS="PARAMETER" +>base</VAR +> +to +<VAR +CLASS="PARAMETER" +>b</VAR +>. +Conversely, +<CODE +CLASS="FUNCTION" +>lwres_buffer_getmem()</CODE +> +copies +<VAR +CLASS="PARAMETER" +>length</VAR +> +bytes of memory from +<VAR +CLASS="PARAMETER" +>b</VAR +> +to +<VAR +CLASS="PARAMETER" +>base</VAR +>.</P +></DIV +></BODY +></HTML +> |
