docs/latex/wx/membuf.tex

   1 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
   2 %% Name:        membuf.tex
   3 %% Purpose:     wxMemoryBuffer class documentation
   4 %% Author:      Roger Gammans
   5 %% Modified by:
   6 %% Created:     08.06.2004
   7 %% RCS-ID:      $Id$
   8 %% Copyright:   (c) Roger Gammans
   9 %% License:     wxWidgets license
  10 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
  11
  12 \section{\class{wxMemoryBuffer}}\label{wxmemorybuffer}
  13
  14 A {\bf wxMemoryBuffer} is a useful data structure for storing arbitrary sized blocks
  15 of memory. wxMemoryBuffer guarantees deletion of the memory block when the object
  16 is destroyed.
  17
  18 \wxheading{Derived from}
  19
  20 None
  21
  22 \wxheading{Include files}
  23
  24 <wx/buffer.h>
  25
  26 \latexignore{\rtfignore{\wxheading{Members}}}
  27
  28 \membersection{wxMemoryBuffer::wxMemoryBuffer}
  29
  30 \func{}{wxMemoryBuffer}{\param{const wxMemoryBuffer\&}{ src}}
  31
  32 Copy constructor, refcounting is used for performance , but wxMemoryBuffer
  33 is not a copy-on-write structure so changes made to one buffer effect
  34 all copies made from it.
  35
  36 \func{}{wxMemoryBuffer}{\param{size\_t}{ size}}
  37
  38 Create a new buffer.
  39
  40 \docparam{size}{size of new buffer.}
  41
  42 \membersection{wxMemoryBuffer::GetData}
  43
  44 \func{void* }{GetData}{\void}
  45
  46 Return a pointer to the data in the buffer.
  47
  48 \membersection{wxMemoryBuffer::GetBufSize}
  49
  50 \func{size\_t}{GetBufSize}{\void}
  51
  52 Returns the size of the buffer.
  53
  54 \membersection{wxMemoryBuffer::GetDataLen}
  55
  56 \func{size\_t}{GetDataLen}{\void}
  57
  58 Returns the length of the valid data in the buffer.
  59
  60 \membersection{wxMemoryBuffer::SetBufSize}
  61
  62 \func{void}{SetBufSize}{\param{size\_t}{ size}}
  63
  64 Ensures the buffer has at least {\it size} bytes available.
  65
  66 \membersection{wxMemoryBuffer::SetDataLen}
  67
  68 \func{void}{SetDataLen}{\param{size\_t}{ size}}
  69
  70 Sets the length of the data stored in the buffer.  Mainly useful for truncating existing data.
  71
  72 \docparam{size}{New length of the valid data in the buffer. This is
  73 distinct from the allocated size}
  74
  75 \membersection{wxMemoryBuffer::GetWriteBuf}
  76
  77 \func{void *}{GetWriteBuf}{\param{size\_t}{ sizeNeeded}}
  78
  79 Ensure the buffer is big enough and return a pointer to the
  80 buffer which can be used to directly write into the buffer
  81 up to {\it sizeNeeded} bytes.
  82
  83 \membersection{wxMemoryBuffer::UngetWriteBuf}
  84
  85 \func{void}{UngetWriteBuf}{\param{size\_t}{ sizeUsed}}
  86
  87 Update the buffer after completing a direct write, which
  88 you must have used GetWriteBuf() to initialise.
  89
  90 \docparam{sizeUsed}{The amount of data written in to buffer
  91 by the direct write}
  92
  93 \membersection{wxMemoryBuffer::GetAppendBuf}
  94
  95 \func{void *}{GetAppendBuf}{\param{size\_t}{ sizeNeeded}}
  96
  97 Ensure that the buffer is big enough and return a pointer to the start
  98 of the empty space in the buffer. This pointer can be used to directly
  99 write data into the buffer, this new data will be appended to
 100 the existing data.
 101
 102 \docparam{sizeNeeded}{Amount of extra space required in the buffer for
 103 the append operation}
 104
 105 \membersection{wxMemoryBuffer::UngetAppendBuf}
 106
 107 \func{void}{UngetAppendBuf}{\param{size\_t}{ sizeUsed}}
 108
 109 Update the length after completing a direct append, which
 110 you must have used GetAppendBuf() to initialise.
 111
 112 \docparam{sizeUsed}{This is the amount of new data that has been
 113 appended.}
 114
 115 \membersection{wxMemoryBuffer::AppendByte}
 116
 117 \func{void}{AppendByte}{\param{char}{ data}}
 118
 119 Append a single byte to the buffer.
 120
 121 \docparam{data}{New byte to append to the buffer.}
 122
 123 \membersection{wxMemoryBuffer::AppendData}
 124
 125 \func{void}{AppendData}{\param{void*}{ data}, \param{size\_t}{ len}}
 126
 127 Single call to append a data block to the buffer.
 128
 129 \docparam{data}{Pointer to block to append to the buffer.}
 130 \docparam{len}{Length of data to append.}