XFA: merge patch from CL 815103002
[pdfium.git] / third_party / freetype / src / sfnt / ttmtx.c
1 /***************************************************************************/
2 /*                                                                         */
3 /*  ttmtx.c                                                                */
4 /*                                                                         */
5 /*    Load the metrics tables common to TTF and OTF fonts (body).          */
6 /*                                                                         */
7 /*  Copyright 2006-2009, 2011-2014 by                                      */
8 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
9 /*                                                                         */
10 /*  This file is part of the FreeType project, and may only be used,       */
11 /*  modified, and distributed under the terms of the FreeType project      */
12 /*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
13 /*  this file you indicate that you have read the license and              */
14 /*  understand and accept it fully.                                        */
15 /*                                                                         */
16 /***************************************************************************/
17
18
19 #include <ft2build.h>
20 #include FT_INTERNAL_DEBUG_H
21 #include FT_INTERNAL_STREAM_H
22 #include FT_TRUETYPE_TAGS_H
23 #include "ttmtx.h"
24
25 #include "sferrors.h"
26
27
28   /*************************************************************************/
29   /*                                                                       */
30   /* The macro FT_COMPONENT is used in trace mode.  It is an implicit      */
31   /* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log  */
32   /* messages during execution.                                            */
33   /*                                                                       */
34 #undef  FT_COMPONENT
35 #define FT_COMPONENT  trace_ttmtx
36
37
38   /*************************************************************************/
39   /*                                                                       */
40   /* <Function>                                                            */
41   /*    tt_face_load_hmtx                                                  */
42   /*                                                                       */
43   /* <Description>                                                         */
44   /*    Load the `hmtx' or `vmtx' table into a face object.                */
45   /*                                                                       */
46   /* <Input>                                                               */
47   /*    face     :: A handle to the target face object.                    */
48   /*                                                                       */
49   /*    stream   :: The input stream.                                      */
50   /*                                                                       */
51   /*    vertical :: A boolean flag.  If set, load `vmtx'.                  */
52   /*                                                                       */
53   /* <Return>                                                              */
54   /*    FreeType error code.  0 means success.                             */
55   /*                                                                       */
56   FT_LOCAL_DEF( FT_Error )
57   tt_face_load_hmtx( TT_Face    face,
58                      FT_Stream  stream,
59                      FT_Bool    vertical )
60   {
61     FT_Error   error;
62     FT_ULong   tag, table_size;
63     FT_ULong*  ptable_offset;
64     FT_ULong*  ptable_size;
65
66
67     if ( vertical )
68     {
69       tag           = TTAG_vmtx;
70       ptable_offset = &face->vert_metrics_offset;
71       ptable_size   = &face->vert_metrics_size;
72     }
73     else
74     {
75       tag           = TTAG_hmtx;
76       ptable_offset = &face->horz_metrics_offset;
77       ptable_size   = &face->horz_metrics_size;
78     }
79
80     error = face->goto_table( face, tag, stream, &table_size );
81     if ( error )
82       goto Fail;
83
84     *ptable_size   = table_size;
85     *ptable_offset = FT_STREAM_POS();
86
87   Fail:
88     return error;
89   }
90
91
92   /*************************************************************************/
93   /*                                                                       */
94   /* <Function>                                                            */
95   /*    tt_face_load_hhea                                                  */
96   /*                                                                       */
97   /* <Description>                                                         */
98   /*    Load the `hhea' or 'vhea' table into a face object.                */
99   /*                                                                       */
100   /* <Input>                                                               */
101   /*    face     :: A handle to the target face object.                    */
102   /*                                                                       */
103   /*    stream   :: The input stream.                                      */
104   /*                                                                       */
105   /*    vertical :: A boolean flag.  If set, load `vhea'.                  */
106   /*                                                                       */
107   /* <Return>                                                              */
108   /*    FreeType error code.  0 means success.                             */
109   /*                                                                       */
110   FT_LOCAL_DEF( FT_Error )
111   tt_face_load_hhea( TT_Face    face,
112                      FT_Stream  stream,
113                      FT_Bool    vertical )
114   {
115     FT_Error        error;
116     TT_HoriHeader*  header;
117
118     static const FT_Frame_Field  metrics_header_fields[] =
119     {
120 #undef  FT_STRUCTURE
121 #define FT_STRUCTURE  TT_HoriHeader
122
123       FT_FRAME_START( 36 ),
124         FT_FRAME_ULONG ( Version ),
125         FT_FRAME_SHORT ( Ascender ),
126         FT_FRAME_SHORT ( Descender ),
127         FT_FRAME_SHORT ( Line_Gap ),
128         FT_FRAME_USHORT( advance_Width_Max ),
129         FT_FRAME_SHORT ( min_Left_Side_Bearing ),
130         FT_FRAME_SHORT ( min_Right_Side_Bearing ),
131         FT_FRAME_SHORT ( xMax_Extent ),
132         FT_FRAME_SHORT ( caret_Slope_Rise ),
133         FT_FRAME_SHORT ( caret_Slope_Run ),
134         FT_FRAME_SHORT ( caret_Offset ),
135         FT_FRAME_SHORT ( Reserved[0] ),
136         FT_FRAME_SHORT ( Reserved[1] ),
137         FT_FRAME_SHORT ( Reserved[2] ),
138         FT_FRAME_SHORT ( Reserved[3] ),
139         FT_FRAME_SHORT ( metric_Data_Format ),
140         FT_FRAME_USHORT( number_Of_HMetrics ),
141       FT_FRAME_END
142     };
143
144
145     if ( vertical )
146     {
147       void  *v = &face->vertical;
148
149
150       error = face->goto_table( face, TTAG_vhea, stream, 0 );
151       if ( error )
152         goto Fail;
153
154       header = (TT_HoriHeader*)v;
155     }
156     else
157     {
158       error = face->goto_table( face, TTAG_hhea, stream, 0 );
159       if ( error )
160         goto Fail;
161
162       header = &face->horizontal;
163     }
164
165     if ( FT_STREAM_READ_FIELDS( metrics_header_fields, header ) )
166       goto Fail;
167
168     FT_TRACE3(( "Ascender:          %5d\n", header->Ascender ));
169     FT_TRACE3(( "Descender:         %5d\n", header->Descender ));
170     FT_TRACE3(( "number_Of_Metrics: %5u\n", header->number_Of_HMetrics ));
171
172     header->long_metrics  = NULL;
173     header->short_metrics = NULL;
174
175   Fail:
176     return error;
177   }
178
179
180   /*************************************************************************/
181   /*                                                                       */
182   /* <Function>                                                            */
183   /*    tt_face_get_metrics                                                */
184   /*                                                                       */
185   /* <Description>                                                         */
186   /*    Return the horizontal or vertical metrics in font units for a      */
187   /*    given glyph.  The values are the left side bearing (top side       */
188   /*    bearing for vertical metrics) and advance width (advance height    */
189   /*    for vertical metrics).                                             */
190   /*                                                                       */
191   /* <Input>                                                               */
192   /*    face     :: A pointer to the TrueType face structure.              */
193   /*                                                                       */
194   /*    vertical :: If set to TRUE, get vertical metrics.                  */
195   /*                                                                       */
196   /*    gindex   :: The glyph index.                                       */
197   /*                                                                       */
198   /* <Output>                                                              */
199   /*    abearing :: The bearing, either left side or top side.             */
200   /*                                                                       */
201   /*    aadvance :: The advance width or advance height, depending on      */
202   /*                the `vertical' flag.                                   */
203   /*                                                                       */
204   FT_LOCAL_DEF( void )
205   tt_face_get_metrics( TT_Face     face,
206                        FT_Bool     vertical,
207                        FT_UInt     gindex,
208                        FT_Short   *abearing,
209                        FT_UShort  *aadvance )
210   {
211     FT_Error        error;
212     FT_Stream       stream = face->root.stream;
213     TT_HoriHeader*  header;
214     FT_ULong        table_pos, table_size, table_end;
215     FT_UShort       k;
216
217
218     if ( vertical )
219     {
220       void*  v = &face->vertical;
221
222
223       header     = (TT_HoriHeader*)v;
224       table_pos  = face->vert_metrics_offset;
225       table_size = face->vert_metrics_size;
226     }
227     else
228     {
229       header     = &face->horizontal;
230       table_pos  = face->horz_metrics_offset;
231       table_size = face->horz_metrics_size;
232     }
233
234     table_end = table_pos + table_size;
235
236     k = header->number_Of_HMetrics;
237
238     if ( k > 0 )
239     {
240       if ( gindex < (FT_UInt)k )
241       {
242         table_pos += 4 * gindex;
243         if ( table_pos + 4 > table_end )
244           goto NoData;
245
246         if ( FT_STREAM_SEEK( table_pos ) ||
247              FT_READ_USHORT( *aadvance ) ||
248              FT_READ_SHORT( *abearing )  )
249           goto NoData;
250       }
251       else
252       {
253         table_pos += 4 * ( k - 1 );
254         if ( table_pos + 4 > table_end )
255           goto NoData;
256
257         if ( FT_STREAM_SEEK( table_pos ) ||
258              FT_READ_USHORT( *aadvance ) )
259           goto NoData;
260
261         table_pos += 4 + 2 * ( gindex - k );
262         if ( table_pos + 2 > table_end )
263           *abearing = 0;
264         else
265         {
266           if ( !FT_STREAM_SEEK( table_pos ) )
267             (void)FT_READ_SHORT( *abearing );
268         }
269       }
270     }
271     else
272     {
273     NoData:
274       *abearing = 0;
275       *aadvance = 0;
276     }
277   }
278
279
280 /* END */