1/***************************************************************************/
2/*                                                                         */
3/*  cf2read.c                                                              */
4/*                                                                         */
5/*    Adobe's code for stream handling (body).                             */
6/*                                                                         */
7/*  Copyright 2007-2013 Adobe Systems Incorporated.                        */
8/*                                                                         */
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35/*                                                                         */
36/***************************************************************************/
37
38
39#include "cf2ft.h"
40#include FT_INTERNAL_DEBUG_H
41
42#include "cf2glue.h"
43
44#include "cf2error.h"
45
46
47  /* Define CF2_IO_FAIL as 1 to enable random errors and random */
48  /* value errors in I/O.                                       */
49#define CF2_IO_FAIL  0
50
51
52#if CF2_IO_FAIL
53
54  /* set the .00 value to a nonzero probability */
55  static int
56  randomError2( void )
57  {
58    /* for region buffer ReadByte (interp) function */
59    return (double)rand() / RAND_MAX < .00;
60  }
61
62  /* set the .00 value to a nonzero probability */
63  static CF2_Int
64  randomValue()
65  {
66    return (double)rand() / RAND_MAX < .00 ? rand() : 0;
67  }
68
69#endif /* CF2_IO_FAIL */
70
71
72  /* Region Buffer                                      */
73  /*                                                    */
74  /* Can be constructed from a copied buffer managed by */
75  /* `FCM_getDatablock'.                                */
76  /* Reads bytes with check for end of buffer.          */
77
78  /* reading past the end of the buffer sets error and returns zero */
79  FT_LOCAL_DEF( CF2_Int )
80  cf2_buf_readByte( CF2_Buffer  buf )
81  {
82    if ( buf->ptr < buf->end )
83    {
84#if CF2_IO_FAIL
85      if ( randomError2() )
86      {
87        CF2_SET_ERROR( buf->error, Invalid_Stream_Operation );
88        return 0;
89      }
90
91      return *(buf->ptr)++ + randomValue();
92#else
93      return *(buf->ptr)++;
94#endif
95    }
96    else
97    {
98      CF2_SET_ERROR( buf->error, Invalid_Stream_Operation );
99      return 0;
100    }
101  }
102
103
104  /* note: end condition can occur without error */
105  FT_LOCAL_DEF( FT_Bool )
106  cf2_buf_isEnd( CF2_Buffer  buf )
107  {
108    return buf->ptr >= buf->end;
109  }
110
111
112/* END */
113