tools/dtdesc/c_iff/newsubform.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/NewSubFORM ****************************************************
  19 *
  20 *   NAME
  21 *       NewSubFORM -- Start a new sub-FORM
  22 *
  23 *   SYNOPSIS
  24 *       Success = NewSubFORM( TheHandle,Type )
  25 *
  26 *       int NewSubFORM( struct IFFHandle *,uint32_t )
  27 *
  28 *   FUNCTION
  29 *       Some IFF's, e.g. ANIM, have cascading FORM's, this means one or
  30 *       more FORM's inside the main-FORM.
  31 *       With NewSubFORM() you can start such a child-FORM.
  32 *
  33 *   INPUTS
  34 *       TheHandle   - IFFHandle to write to
  35 *       Type        - type of the sub-FORM
  36 *
  37 *   RESULT
  38 *       Success     - TRUE when the FORM-header is succesfully written,
  39 *                     otherwise FALSE
  40 *
  41 *   EXAMPLE
  42 *
  43 *   NOTES
  44 *       Sub-FORM's startet with NewSubFORM() must be finished
  45 *       with EndChunk() to correct the internal size.
  46 *
  47 *   BUGS
  48 *
  49 *   SEE ALSO
  50 *       EndChunk()
  51 *
  52 *****************************************************************************
  53 *
  54 *       Private notes:
  55 */
  56
  57 int NewSubFORM(struct IFFHandle *TheHandle, uint32_t Type)
  58 {
  59  uint32_t Buffer[3];
  60  struct ChunkNode *CN, *PN;
  61
  62  if(!TheHandle)
  63  {
  64   return(FALSE);
  65  }
  66
  67  CN=(struct ChunkNode *) malloc(sizeof(struct ChunkNode));
  68  if(!CN)
  69  {
  70   return(FALSE);
  71  }
  72
  73  Buffer[0]=ID_FORM;
  74  Buffer[1]=0;
  75  Buffer[2]=Type;
  76
  77  Buffer[0]=Swap32IfLE(Buffer[0]);
  78  Buffer[1]=Swap32IfLE(Buffer[1]);
  79  Buffer[2]=Swap32IfLE(Buffer[2]);
  80
  81  if(!(fwrite((void *) Buffer, sizeof(uint32_t), 3, TheHandle->TheFile)==3))
  82  {
  83   free((void *) CN);
  84   return(FALSE);
  85  }
  86
  87  CN->Size=sizeof(uint32_t);
  88  CN->FilePos=ftell(TheHandle->TheFile);
  89  CN->FilePos-=8;
  90  CN->Previous=TheHandle->LastNode;
  91
  92  PN=CN->Previous;
  93
  94  while(PN)
  95  {
  96   PN->Size+=3*sizeof(uint32_t);
  97
  98   PN=PN->Previous;
  99  }
 100
 101  TheHandle->IFFSize+=3*sizeof(uint32_t);
 102  TheHandle->LastNode=CN;
 103
 104  return(TRUE);
 105 }
 106
 107