tools/dtdesc/c_iff/newchunk.c

   1 /*
   2  *  c_iff - a portable IFF-parser
   3  *
   4  *  Copyright (C) 2000, 2001 Joerg Dietrich
   5  *
   6  *  This is the AROS-version of c_iff.
   7  *  It is distributed under the AROS Public License.
   8  *  But I reserve the right to distribute
   9  *  my own version under other licenses.
  10  */
  11
  12 /*
  13  *  newchunk.c - open a new chunk
  14  */
  15
  16 #include "c_iff.h"
  17
  18 /****** c_iff/NewChunk ******************************************************
  19 *
  20 *   NAME
  21 *       NewChunk -- Start a new chunk
  22 *
  23 *   SYNOPSIS
  24 *       Success = NewChunk( TheHandle,ID )
  25 *
  26 *       int NewChunk( struct IFFHandle *,uint32_t )
  27 *
  28 *   FUNCTION
  29 *       Starts a new chunk, trough writing the chunk-header.
  30 *
  31 *   INPUTS
  32 *       TheHandle   - IFFHandle to write to
  33 *       ID          - ID of the chunk
  34 *
  35 *   RESULT
  36 *       Success     - TRUE when chunk-header is succesfully written,
  37 *                     otherwise FALSE
  38 *
  39 *   EXAMPLE
  40 *
  41 *   NOTES
  42 *       Chunks startet with NewChunk() must be finished with EndChunk()
  43 *       to correct the internal chunk-size.
  44 *
  45 *   BUGS
  46 *
  47 *   SEE ALSO
  48 *       EndChunk()
  49 *
  50 *****************************************************************************
  51 *
  52 *       Private notes:
  53 */
  54
  55 int NewChunk(struct IFFHandle *TheHandle, uint32_t ID)
  56 {
  57  uint32_t Buffer[2];
  58  struct ChunkNode *CN, *PN;
  59
  60  if(!TheHandle)
  61  {
  62   return(FALSE);
  63  }
  64
  65  CN=(struct ChunkNode *) malloc(sizeof(struct ChunkNode));
  66  if(!CN)
  67  {
  68   return(FALSE);
  69  }
  70
  71  Buffer[0]=ID;
  72  Buffer[1]=0;
  73
  74  Buffer[0]=Swap32IfLE(Buffer[0]);
  75  Buffer[1]=Swap32IfLE(Buffer[1]);
  76
  77  if(!(fwrite((void *) Buffer, sizeof(uint32_t), 2, TheHandle->TheFile)==2))
  78  {
  79   free((void *) CN);
  80   return(FALSE);
  81  }
  82
  83  CN->Size=0;
  84  CN->FilePos=ftell(TheHandle->TheFile);
  85  CN->FilePos-=sizeof(uint32_t);
  86  CN->Previous=TheHandle->LastNode;
  87
  88  PN=CN->Previous;
  89
  90  while(PN)
  91  {
  92   PN->Size+=2*sizeof(uint32_t);
  93
  94   PN=PN->Previous;
  95  }
  96
  97  TheHandle->IFFSize+=2*sizeof(uint32_t);
  98  TheHandle->LastNode=CN;
  99
 100  return(TRUE);
 101 }
 102
 103