1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
|
#ifndef __FT_SYSTEM_IO_H__
#define __FT_SYSTEM_IO_H__
/************************************************************************/
/************************************************************************/
/***** *****/
/***** NOTE: THE CONTENT OF THIS FILE IS NOT CURRENTLY USED *****/
/***** IN NORMAL BUILDS. CONSIDER IT EXPERIMENTAL. *****/
/***** *****/
/************************************************************************/
/************************************************************************/
/********************************************************************
*
* designing custom streams is a bit different now
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*/
#include <ft2build.h>
#include FT_INTERNAL_OBJECT_H
FT_BEGIN_HEADER
/*@*******************************************************************
*
* @type: FT_Stream
*
* @description:
* handle to an input stream object. These are also @FT_Object handles
*/
typedef struct FT_StreamRec_* FT_Stream;
/*@*******************************************************************
*
* @type: FT_Stream_Class
*
* @description:
* opaque handle to a @FT_Stream_ClassRec class structure describing
* the methods of input streams
*/
typedef const struct FT_Stream_ClassRec_* FT_Stream_Class;
/*@*******************************************************************
*
* @functype: FT_Stream_ReadFunc
*
* @description:
* a method used to read bytes from an input stream into memory
*
* @input:
* stream :: target stream handle
* buffer :: target buffer address
* size :: number of bytes to read
*
* @return:
* number of bytes effectively read. Must be <= 'size'.
*/
typedef FT_ULong (*FT_Stream_ReadFunc)( FT_Stream stream,
FT_Byte* buffer,
FT_ULong size );
/*@*******************************************************************
*
* @functype: FT_Stream_SeekFunc
*
* @description:
* a method used to seek to a new position within a stream
*
* @input:
* stream :: target stream handle
* pos :: new read position, from start of stream
*
* @return:
* error code. 0 means success
*/
typedef FT_Error (*FT_Stream_SeekFunc)( FT_Stream stream,
FT_ULong pos );
/*@*******************************************************************
*
* @struct: FT_Stream_ClassRec
*
* @description:
* a structure used to describe an input stream class
*
* @input:
* clazz :: root @FT_ClassRec fields
* stream_read :: stream byte read method
* stream_seek :: stream seek method
*/
typedef struct FT_Stream_ClassRec_
{
FT_ClassRec clazz;
FT_Stream_ReadFunc stream_read;
FT_Stream_SeekFunc stream_seek;
} FT_Stream_ClassRec;
/* */
#define FT_STREAM_CLASS(x) ((FT_Stream_Class)(x))
#define FT_STREAM_CLASS__READ(x) FT_STREAM_CLASS(x)->stream_read
#define FT_STREAM_CLASS__SEEK(x) FT_STREAM_CLASS(x)->stream_seek;
/*@*******************************************************************
*
* @struct: FT_StreamRec
*
* @description:
* the input stream object structure. See @FT_Stream_ClassRec for
* its class descriptor
*
* @fields:
* object :: root @FT_ObjectRec fields
* size :: size of stream in bytes (0 if unknown)
* pos :: current position within stream
* base :: for memory-based streams, the address of the stream's
* first data byte in memory. NULL otherwise
*
* cursor :: the current cursor position within an input stream
* frame. Only valid within a FT_FRAME_ENTER .. FT_FRAME_EXIT
* block; NULL otherwise
*
* limit :: the current frame limit within a FT_FRAME_ENTER ..
* FT_FRAME_EXIT block. NULL otherwise
*/
typedef struct FT_StreamRec_
{
FT_ObjectRec object;
FT_ULong size;
FT_ULong pos;
const FT_Byte* base;
const FT_Byte* cursor;
const FT_Byte* limit;
} FT_StreamRec;
/* some useful macros */
#define FT_STREAM(x) ((FT_Stream)(x))
#define FT_STREAM_P(x) ((FT_Stream*)(x))
#define FT_STREAM__READ(x) FT_STREAM_CLASS__READ(FT_OBJECT__CLASS(x))
#define FT_STREAM__SEEK(x) FT_STREAM_CLASS__SEEK(FT_OBJECT__CLASS(x))
#define FT_STREAM_IS_BASED(x) ( FT_STREAM(x)->base != NULL )
/* */
/* create new memory-based stream */
FT_BASE( FT_Error ) ft_stream_new_memory( const FT_Byte* stream_base,
FT_ULong stream_size,
FT_Memory memory,
FT_Stream *astream );
FT_BASE( FT_Error ) ft_stream_new_iso( const char* pathanme,
FT_Memory memory,
FT_Stream *astream );
/* handle to default stream class implementation for a given build */
/* this is used by "FT_New_Face" */
/* */
FT_APIVAR( FT_Type ) ft_stream_default_type;
FT_END_HEADER
#endif /* __FT_SYSTEM_STREAM_H__ */
|
