Kernel/adt.c

   1 /*
   2  * Acess2 Kernel
   3  *
   4  * adt.c
   5  * - Complex data type code
   6  */
   7 #include <acess.h>
   8 #include <adt.h>
   9
  10
  11 // === CODE ===
  12 // --- Ring Buffers ---
  13 tRingBuffer *RingBuffer_Create(size_t Space)
  14 {
  15         tRingBuffer     *ret = malloc(sizeof(tRingBuffer)+Space);
  16         ret->Start = 0;
  17         ret->Length = 0;
  18         ret->Space = Space;
  19         return ret;
  20 }
  21
  22 size_t RingBuffer_Read(void *Dest, tRingBuffer *Buffer, size_t Length)
  23 {
  24         if(Length > Buffer->Length)     Length = Buffer->Length;
  25
  26         if( Buffer->Start + Length > Buffer->Space )
  27         {
  28                  int    endData = Buffer->Space - Buffer->Start;
  29                 memcpy(Dest, &Buffer->Data[Buffer->Start], endData);
  30                 memcpy((Uint8*)Dest + endData, &Buffer->Data, Length - endData);
  31         }
  32         else
  33         {
  34                 memcpy(Dest, &Buffer->Data[Buffer->Start], Length);
  35         }
  36         Buffer->Start += Length;
  37         if( Buffer->Start > Buffer->Space )
  38                 Buffer->Start -= Buffer->Space;
  39         Buffer->Length -= Length;
  40         return Length;
  41 }
  42
  43 size_t RingBuffer_Write(tRingBuffer *Buffer, const void *Source, size_t Length)
  44 {
  45         size_t  bufEnd = Buffer->Start + Buffer->Length;
  46         size_t  endSpace = Buffer->Space - bufEnd;
  47
  48         // Force to bounds
  49         if(Length > Buffer->Space - Buffer->Length)
  50                 Length = Buffer->Space - Buffer->Length;
  51
  52         if(endSpace < Length)
  53         {
  54                 memcpy( &Buffer->Data[bufEnd], Source, endSpace );
  55                 memcpy( Buffer->Data, (Uint8*)Source + endSpace, Length - endSpace );
  56                 Buffer->Length = Length - endSpace;
  57         }
  58         else
  59         {
  60                 memcpy( &Buffer->Data[bufEnd], Source, Length );
  61                 Buffer->Length += Length;
  62         }
  63
  64         return Length;
  65 }